Statistical Difference In Rate Research Articles

Imatinib for Melanomas Harboring Mutationally Activated or Amplified KIT Arising on Mucosal, Acral, and Chronically Sun-Damaged Skin

Amplifications and mutations in the KIT proto-oncogene in subsets of melanomas provide therapeutic opportunities. We conducted a multicenter phase II trial of imatinib in metastatic mucosal, acral, or chronically sun-damaged (CSD) melanoma with KIT amplifications and/or mutations. Patients received imatinib 400 mg once per day or 400 mg twice per day if there was no initial response. Dose reductions were permitted for treatment-related toxicities. Additional oncogene mutation screening was performed by mass spectroscopy. Twenty-five patients were enrolled (24 evaluable). Eight patients (33%) had tumors with KIT mutations, 11 (46%) with KIT amplifications, and five (21%) with both. Median follow-up was 10.6 months (range, 3.7 to 27.1 months). Best overall response rate (BORR) was 29% (21% excluding nonconfirmed responses) with a two-stage 95% CI of 13% to 51%. BORR was significantly greater than the hypothesized null of 5% and statistically significantly different by mutation status (7 of 13 or 54% KIT mutated v 0% KIT amplified only). There were no statistical differences in rates of progression or survival by mutation status or by melanoma site. The overall disease control rate was 50% but varied significantly by KIT mutation status (77% mutated v 18% amplified). Four patients harbored pretreatment NRAS mutations, and one patient acquired increased KIT amplification after treatment. Melanomas that arise on mucosal, acral, or CSD skin should be assessed for KIT mutations. Imatinib can be effective when tumors harbor KIT mutations, but not if KIT is amplified only. NRAS mutations and KIT copy number gain may be mechanisms of therapeutic resistance to imatinib.

Return to Play After Hip Arthroscopy With Microfracture in Elite Athletes

The purpose of this study was to compare elite athletes who underwent hip arthroscopy with and without microfracture with respect to their ability to return to sport at the professional level. All elite male athletes who underwent hip arthroscopy between 1999 and 2010 were identified. Inclusion criteria were hip arthroscopy with treatment of labrum, femoroacetabular impingement, cartilage, ligamentum teres, capsule, and/or loose body removal. Exclusion criteria were diffuse degenerative joint disease, previous surgery, plans to retire, labral reconstruction, soft tissue release, and concomitant lower extremity injury. Thirty-nine athletes underwent hip arthroscopy with microfracture and were assigned to the microfracture treatment group. Eighty-one elite athletes (94 hips) underwent hip arthroscopy without microfracture and were assigned to the control group. Sports played included hockey, soccer, football, baseball, tennis, and golf. Seventy-seven percent (30 of 39) of athletes in the microfracture treatment group and 84% (79 of 94) in the control group returned to play. There was no statistical difference in rate of return to play between groups (odds ratio= 1.6; 95% confidence interval, 0.633 to 4.049). Those players who did return were followed for an average of 3 years (range, 2 to 12). Athletes in the microfracture treatment group who returned have averaged 3 seasons thus far, and 73% are still playing. We found no significant difference in the microfracture group in age, time from injury to surgery, number of seasons played preoperatively, or size of lesion for return versus no return. We also found no increased risk of not returning because of contact sport, multiple lesions, or lesion on weightbearing surface. There was no detectable statistically significant difference in return to play rate after hip arthroscopy with microfracture and hip arthroscopy without microfracture. Professional athletes who underwent hip arthroscopy with microfracture procedure were able to return to the same high level of competition after surgery at a high rate. Level III, retrospective comparative study.

Procalcitonin-guided algorithms of antibiotic therapy in community-acquired lower respiratory tract infections: a systematic review and meta-analysis of randomized controlled trials

The aim of this study was to evaluate the efficacy and safety of procalcitonin-guided algorithms of antibiotic therapy in lower respiratory tract infections. Using procalcitonin, lower respiratory tract infections, community acquired pneumonia, exacerbations of COPD, exacerbations of chronic obstructive pulmonary diseases, acute bronchitis and asthma as key words, we searched relevant randomized controlled trials (RCT) from Pubmed, EMBASE, Cochrane Library, Chinese Journal Full-text Database, Chinese Biomedical Literature Database, and traced the related references to obtain the information that had not been found. The date of the search was from January of 1990 to December of 2010.We made quality assessment of qualified RCTs assessed by the exclusion and inclusion criteria and used RevMan 4.2.2 provided by the Cochrane Collaboration to perform meta-analysis. Five RCT involving 2322 patients were identified. There were significant differences between procalcitonin-guided treatment and standard treatment in duration of antibiotic treatment in days (WMD = -2.58 d, 95%CI: -3.13 to -2.04, Z = 9.36, P < 0.001), antibiotic prescription rate (OR = 0.23, 95%CI: 0.12 - 0.44, Z = 4.52, P < 0.001), antibiotic costs (WMD = USD-91.72, 95%CI: -109.44 to -74.00, Z = 10.15, P < 0.001) and persistent/relapsed infection rate (OR = 0.70, 95%CI: 0.5 - 0.97, Z = 2.13, P = 0.03). There were no statistical differences in rate of need for intensive care (OR = 0.8, 95%CI: 0.59 - 1.09, Z = 1.41, P = 0.16), in hospital mortality (OR = 1.01, 95%CI: 0.69 - 1.48, Z = 0.07, P = 0.94), length of hospital stay (WMD = -0.27 d, 95%CI: -0.9 - 0.35, Z = 0.86, P = 0.39), and clinical success rate (OR = 1.04, 95%CI: 0.65 - 1.65, Z = 0.16, P = 0.88). The implementation of a procalcitonin-based algorithm may reduce antibiotic exposure in patients with lower respiratory tract infections, but further research is necessary before the wide adoption of this strategy.

Hyperparathyroidism and Complications Associated with Vitamin D Deficiency in HIV-Infected Adults in New York City, New York

Although recent studies report a high prevalence of vitamin D deficiency in HIV-infected adults similar to that in the general population, metabolic complications of vitamin D deficiency may be worsened with HIV infection and remain insufficiently characterized. We conducted a retrospective cross-sectional cohort study to determine prevalence and correlates of vitamin D deficiency and hyperparathyroidism among HIV-infected patients attending an urban clinic. Vitamin D deficiency was defined as 25(OH)-vitamin D <20 ng/ml and insufficiency as 20 to <30 ng/ml, and hyperparathyroidism as parathyroid-hormone >65 pg/ml. We used the X(2) test to compare proportions and logistic regression to assess for associations. Among 463 HIV-infected patients, the prevalence of vitamin D deficiency was 59%. The prevalence of hyperparathyroidism was 30% among patients with vitamin D deficiency, 23% among those with insufficiency, and 12% among those with sufficient vitamin D levels. Vitamin D deficiency was associated with increased odds of hyperparathyroidism. Severe vitamin D deficiency was associated with elevated alkaline phosphatase, a marker for increased bone turnover. Although efavirenz use was associated with vitamin D deficiency, and protease inhibitor use with decreased odds of vitamin D deficiency, there was no statistical difference in rates of hyperparathyroidism stratified by combination antiretroviral therapy (cART) use. Given the increased risk of osteopenia with HIV infection and cART use, vitamin D supplementation for all HIV-infected patients on cART should be prescribed in accordance with the 2011 Endocrine Society guidelines. In HIV-infected patients with severe vitamin D deficiency or hyperparathyroidism, screening for osteomalacia and osteopenia may be warranted.

Necrotizing Fasciitis

Necrotizing fasciitis (NF) is a life-threatening infectious disease whose incidence has been on the rise. Commonly a consequence of group A beta-hemolytic Streptococcus infection, it results in high levels of morbidity and mortality. Diagnosis is difficult and treatment involves emergent surgical intervention and antibiotic therapy. The aim of this study is to examine the incidence of NF in Manitoba with the goal of observing whether there is a geographic variation in incidence and outcomes based on Regional Health Authorities (RHAs). This is a 6-year retrospective chart review of all NF patients who presented to the Health Sciences Center from 2004 to 2009. A total of 130 patients satisfied the inclusion criteria. The mean age was 47 ± 16 years. The most common comorbidities were diabetes (33.8%) and hypertension (33.1%). The overall mortality was 13.1% with advanced age being an independent risk factor (P < .05). Lower extremity was the most common location of infection (44.6%) and the most common causative organism was group A beta-hemolytic Streptococcus (63.9%). The type of infection (mono- vs. polymicrobial) was not found to affect length of stay, amputation rate, or mortality. There was no statistical difference in rate of amputations, length of stay, or mortality based on RHA. Incidence within the province, however, varied significantly based on RHA and ethnicity (P < .05). We determined that regardless of origin before admission, all our patients have equivalent prognosis. Burntwood RHA was found to have substantially higher incidence than the rest of the province, and higher incidence was established among the Aboriginal population.

Comparison of ventilator-associated pneumonia (VAP) rates between different ICUs: Implications of a zero VAP rate

ObjectiveVentilator-associated pneumonia (VAP) is associated with significant morbidity and mortality. Measures to reduce the incidence of VAP have resulted in institutions reporting a zero or near-zero VAP rates. The implications of zero VAP rates are unclear. This study was done to compare outcomes between two intensive care units (ICU) with one of them reporting a zero VAP rate. Design, Setting and PatientsThis study retrospectively compared VAP rates between two ICUs: Utah Valley Regional Medical Center (UVRMC) with 25 ICU beds and American Fork Hospital (AFH) with 9 ICU beds. Both facilities are under the same management and attended by a single group of intensivists. Both ICUs have similar nursing and respiratory staffing patterns. Both ICUs use the same intensive care program for reduction of VAP rates. ICU outcomes between AFH (reporting zero VAP rate) and UVRMC (VAP rate of 2.41/1000 ventilator days) were compared for the years 2007-2008. Measurements and Main ResultsUVRMC VAP rates during 2007 and 2008 were 2.31/1000 ventilator days and 2.5/1000 ventilator days respectively compared to a zero VAP rate at AFH. The total days of ventilation, mean days of ventilation per patient and mean duration of ICU stay per patient was higher in the UVRMC group as compared to AFH ICU group. There was no significant difference in mean age and APACHE II score between ICU patients at UVRMC and AFH. There was no statistical difference in rates of VAP and mortality between UVRMC and AFH. ConclusionsDuring comparisons of VAP rate between institutions, a zero VAP rate needs to be considered in the context of overall ventilator days, mean durations of ventilator stay and ICU mortality.

Prospective randomised study to evaluate the use of DERMABOND ProPen (2-octylcyanoacrylate) in the closure of abdominal wounds versus closure with skin staples in patients undergoing elective colectomy

Topical 2-octylcyanoacrylate tissue (OCA) adhesive has been used as an alternative to close wounds with a comparable cosmetic outcome. The use of 2-OCA in the closure of abdominal laparotomy wounds has not been thoroughly evaluated. Our aim was to compare 2-OCA with conventional skin stapling devices in colorectal surgery. A prospective randomised study was conducted in which 74 consecutive patients above the age of 21 undergoing open elective colectomies for benign or malignant indications were allocated to skin closure with 2-OCA or skin staples. Cosmetic outcome as assessed with the Hollander Cosmesis Scale with a single assessor, complication rates, and patient satisfaction were recorded at discharge (4-10POD) 2 weeks after discharge and then at 3 months. Of the 74 patients, 38 were randomised to skin staples and 36 to 2-OCA. There was no significant difference in cosmetic outcomes between the two groups as assessed with a visual analogue scale or the Hollander Cosmesis Scale but showed a trend to better cosmetic outcomes in the 2-OCA group. Patient satisfaction scores were higher but did not reach statistical significance. The time taken to close a wound with 2-OCA was significantly longer than with skin staples. There was no statistical difference in rates of wound infection. 2-OCA is a safe and effective means of skin closure in patients undergoing elective colectomies with a good and at least equivalent outcome to traditional methods of closure.

Antiretroviral Therapy Initiation Before, During, or After Pregnancy in HIV-1-Infected Women: Maternal Virologic, Immunologic, and Clinical Response

BackgroundPregnancy has been associated with a decreased risk of HIV disease progression in the highly active antiretroviral therapy (HAART) era. The effect of timing of HAART initiation relative to pregnancy on maternal virologic, immunologic and clinical outcomes has not been assessed.MethodsWe conducted a retrospective cohort study from 1997–2005 among 112 pregnant HIV-infected women who started HAART before (N = 12), during (N = 70) or after pregnancy (N = 30).ResultsWomen initiating HAART before pregnancy had lower CD4+ nadir and higher baseline HIV-1 RNA. Women initiating HAART after pregnancy were more likely to receive triple-nucleoside reverse transcriptase inhibitors. Multivariable analyses adjusted for baseline CD4+ lymphocytes, baseline HIV-1 RNA, age, race, CD4+ lymphocyte count nadir, history of ADE, prior use of non-HAART ART, type of HAART regimen, prior pregnancies, and date of HAART start. In these models, women initiating HAART during pregnancy had better 6-month HIV-1 RNA and CD4+ changes than those initiating HAART after pregnancy (−0.35 vs. 0.10 log10 copies/mL, P = 0.03 and 183.8 vs. −70.8 cells/mm3, P = 0.03, respectively) but similar to those initiating HAART before pregnancy (−0.32 log10 copies/mL, P = 0.96 and 155.8 cells/mm3, P = 0.81, respectively). There were 3 (25%) AIDS-defining events or deaths in women initiating HAART before pregnancy, 3 (4%) in those initiating HAART during pregnancy, and 5 (17%) in those initiating after pregnancy (P = 0.01). There were no statistical differences in rates of HIV disease progression between groups.ConclusionsHAART initiation during pregnancy was associated with better immunologic and virologic responses than initiation after pregnancy.

The Very Model of a Modern Doctor General

<h3>Purpose</h3> Greater than 200,000 children per year are evaluated in US emergency departments because of playground injuries. A minority of these visits (23%) occur on home playgrounds, whereas 70% of playground deaths occur at home. Few data exist to further describe injuries occurring on home and public playgrounds that are not life-threatening. In this study, we sought to determine if more serious injuries occur on home playgrounds compared with public playgrounds. <h3>Methods</h3> An injury surveillance form was developed in our emergency department 2 years ago to identify several major types of injuries and to describe the circumstances leading to injury occurrence. These forms are included with every chart for children presenting to the emergency department with complaints of any type of injury. An assistant separated these forms by method of injury: sports, falls, bicycle, vehicle, playground, or burn. Epidemiologic data were extracted from each playground injury form and was then entered into <i>Epistat</i>® and a <i>z</i>-test of proportions was used for statistical analysis. <h3>Results</h3> Between March and August 2006, 106 children were identified as having playground injuries. Of these, 56% were male and ages ranged from 2 to 15 years old, with a median age of 6. Most injuries occurred on public playgrounds (70%). The types of injuries sustained include fractures (48%), lacerations (19%), and closed head traumas (18%). The remaining 15% of injuries were relatively minor: sprains, strains, abrasions, and isolated pain. Admission was necessary for 9% of our population. When comparing injuries that occurred at home versus those that occurred at a public playground, there was no statistical difference in rate of admission (<i>z</i> = −0.23, <i>p</i> = .82 [−0.13, 0.11]). Between these two groups, we also found no statistical difference in numbers of fractures (<i>z</i> = 1.11, <i>p</i> = 0.27 [−0.35, 0.07]), in numbers of closed head traumas (<i>z</i> = 0.77, <i>p</i> = .44 [−0.08, 0.25]), or in numbers of lacerations (<i>z</i> = −0.16, <i>p</i> = .87 [−0.16, 0.17]). <h3>Conclusion</h3> This information shows that in our population, the types of injuries that occur on home playgrounds are not more serious than those that occur on public playgrounds. Significant injuries do occur on both home and public playgrounds; 85% of the injuries children sustained in this study were fractures, closed head traumas, and lacerations. Increased effort should be applied to making playgrounds safer for children in both types of environments.

Clinical utility of Liqui-PREP™ cytology system for primary cervical cancer screening in a large urban hospital setting in China.

Background:Liquid based cytology (LBC) has been reported to increase the sensitivity of cervical cytology, in comparison with conventional cytology Pap smear (CPS). Most LBC systems though require expensive automated devices.Aims:To evaluate the efficiency of a new and inexpensive LBC system - LPT cytology system.Materials and Methods:Cervical screening was performed on 31500 patients utilizing the LPT cytology system test from January 2006 to May 2007. A similar number (n = 31500) of CPS were performed from January 2004 to July 2006. All cytology positive patients underwent colposcopy and cervical biopsy with histopathology examination. Fifty cases positive both on cytology and biopsy were submitted to the high-risk human papillomavirus (HPV) L1 protein (HR-HPV L1) tests.Results:The LPT cytology system adequately preserved cellular structure for morphologic evaluation. There was a significant difference of the histology/cytology diagnosis concordant rate between that of the CPS and LPT systems [93.6 vs. 78.4%, p=0.001]. The significant higher concordant rate was also seen in the low grade intraepithelial lesion (LSIL) (95.4 vs. 78.9%, p=0.001) and in high grade intraepithelial lesion (HSIL) (90.2 vs. 76.1%, p=0.001) cytology diagnosis. There was no statistical difference in rate in atypical glandular cells (AGC) (61.5 vs. 60%) and glandular cell carcinoma (GCC) (83.3 vs. 80%). LPT resulted in a marked increased global detection over the CPS. Nuclear expression of HPV L1 was seen in 34% (17/50) of cases.Conclusions:LPT showed an increase in detection rate compared to CPS (P = 0.001) and a significantly higher histological versus cytological concordant referral rate.

Analysis of Transnasal Endoscopic versus Transseptal Microscopic Approach for Excision of Pituitary Tumors

The traditional method of pituitary tumor excision is transseptal microscopic excision; however, the transnasal transsphenoidal endoscopic approach has shown comparable results with the transseptal microscopic approach at some institutions. The objective of this study is to compare the two types of sellar and parasellar mass resection: transnasal transsphenoidal endoscopic excision versus transseptal microscopic excision. A retrospective cohort analysis was performed on subjects who were referred to a tertiary hospital for surgical management of sellar or parasellar masses. The two groups of patients either underwent a transnasal endoscopic approach with endoscopic excision or transseptal microscopic excision. Demographics, tumor characteristics, operative details, length of hospital stay, intraoperative and postoperative complications, level of postoperative pain, recurrence rate, use of computed tomography (CT) image guidance, and length of follow-up were gathered. The data between the two groups were then compared. The analysis included 19 subjects who underwent endoscopic excision and 29 subjects who underwent transseptal microscopic excision. Null macroadenoma was the most common sellar mass followed by prolactinoma. There were no statistical differences in rates of perioperative complications and suprasellar or cavernous sinus invasion. Patients who underwent an endoscopic approach had shorter operative times, lower estimated blood loss, less lumbar drain use, less pain, and a shorter postoperative hospital stay (p < 0.05). The two approaches show similar intraoperative characteristics and immediate complication rates. Transnasal transsphenoidal endoscopic excision is a reasonable alternative to the traditional method of sellar mass excision.

Human sensitivity to reinforcement feedback functions

Two experiments investigated human sensitivity to the temporally extended aspects of reinforcement schedules. Experiment 1 investigated human sensitivity to the extended and local aspects of three reinforcement schedules: variable ratio (VR), variable interval (VI), and variable-interval-plus-linear-feedback (VI+) schedules. Experiment 2 investigated this sensitivity on two reinforcement schedules: VI and VI+ schedules. In both experiments, there was evidence of sensitivity to the temporally extended aspects of the schedule: There were differences between the response rate on the VI+ and yoked-VI schedules, but no statistical difference in rates of response between the VR and VI+ schedules. The VI+ versus VI difference was much more pronounced when a lower response force needed to depress a lever was used. These results suggest that human subjects do show some sensitivity to temporally extended aspects of schedules of reinforcement.

ARE INJURIES THAT OCCUR ON HOME PLAYROUNDS MORE SERIOUS THAN THOSE THAT OCCUR ON PUBLIC PLAYGROUNDS?

Purpose Greater than 200,000 children per year are evaluated in US emergency departments because of playground injuries. A minority of these visits (23%) occur on home playgrounds, whereas 70% of playground deaths occur at home. Few data exist to further describe injuries occurring on home and public playgrounds that are not life-threatening. In this study, we sought to determine if more serious injuries occur on home playgrounds compared with public playgrounds. Methods An injury surveillance form was developed in our emergency department 2 years ago to identify several major types of injuries and to describe the circumstances leading to injury occurrence. These forms are included with every chart for children presenting to the emergency department with complaints of any type of injury. An assistant separated these forms by method of injury: sports, falls, bicycle, vehicle, playground, or burn. Epidemiologic data were extracted from each playground injury form and was then entered into Epistat® and a z-test of proportions was used for statistical analysis. Results Between March and August 2006, 106 children were identified as having playground injuries. Of these, 56% were male and ages ranged from 2 to 15 years old, with a median age of 6. Most injuries occurred on public playgrounds (70%). The types of injuries sustained include fractures (48%), lacerations (19%), and closed head traumas (18%). The remaining 15% of injuries were relatively minor: sprains, strains, abrasions, and isolated pain. Admission was necessary for 9% of our population. When comparing injuries that occurred at home versus those that occurred at a public playground, there was no statistical difference in rate of admission (z = −0.23, p = .82 [−0.13, 0.11]). Between these two groups, we also found no statistical difference in numbers of fractures (z = 1.11, p = 0.27 [−0.35, 0.07]), in numbers of closed head traumas (z = 0.77, p = .44 [−0.08, 0.25]), or in numbers of lacerations (z = −0.16, p = .87 [−0.16, 0.17]). Conclusion This information shows that in our population, the types of injuries that occur on home playgrounds are not more serious than those that occur on public playgrounds. Significant injuries do occur on both home and public playgrounds; 85% of the injuries children sustained in this study were fractures, closed head traumas, and lacerations. Increased effort should be applied to making playgrounds safer for children in both types of environments.

Effects of epidural lidocaine analgesia on labor and delivery: A randomized, prospective, controlled trial

BackgroundWhether epidural analgesia for labor prolongs the active-first and second labor stages and increases the risk of vacuum-assisted delivery is a controversial topic. Our study was conducted to answer the question: does lumbar epidural analgesia with lidocaine affect the progress of labor in our obstetric population?Method395 healthy, nulliparous women, at term, presented in spontaneous labor with a singleton vertex presentation. These patients were randomized to receive analgesia either, epidural with bolus doses of 1% lidocaine or intravenous, with meperidine 25 to 50 mg when their cervix was dilated to 4 centimeters. The duration of the active-first and second stages of labor and the neonatal apgar scores were recorded, in each patient. The total number of vacuum-assisted and cesarean deliveries were also measured.Results197 women were randomized to the epidural group. 198 women were randomized to the single-dose intravenous meperidine group. There was no statistical difference in rates of vacuum-assisted delivery rate. Cesarean deliveries, as a consequence of fetal bradycardia or dystocia, did not differ significantly between the groups. Differences in the duration of the active-first and the second stages of labor were not statistically significant. The number of newborns with 1-min and 5-min Apgar scores less than 7, did not differ significantly between both analgesia groups.ConclusionEpidural analgesia with 1% lidocaine does not prolong the active-first and second stages of labor and does not increase vacuum-assisted or cesarean delivery rate.

Toxicity following 3D radiation therapy for prostate cancer on RTOG 9406 dose level V

Toxicity following 3D radiation therapy for prostate cancer on RTOG 9406 dose level V

Does primary tracheoesophageal puncture reduce complications after laryngectomy and improve patient communication?

The charts of 96 patients who had a laryngectomy at the University of Minnesota and affiliated hospitals were reviewed to assess the benefit of primary tracheoesophageal puncture (TEP). Patients were stratified into those with primary TEP and those without. There was no statistical difference in rates of esophageal stenosis, stomal stenosis, or wound breakdown without fistula. No fistulas developed in 33 patients who received primary TEP. 52% Of those with primary TEP, used their prosthesis for speech long-term. Only 5 of 63 patients whose surgery did not include primary TEP, received a secondary TEP, and only 2 retained the prosthesis for speech. There was no increased morbidity or incidence of complications after laryngectomy when performing a primary TEP. Patients will maintain the initial form of speech rehabilitation, even if it is less comprehensible. The early postoperative period is convenienced by using the puncture site as the entrance for nutrition during wound healing. (Am J Otolaryngol 2001;22:324-328. Copyright © 2001 by W.B. Saunders Company)

Mass movement of mancos shale crust near caineville, utah: a 30‐year record

Rates of soil creep were studied periodically over a 30‐year period in southeastern Utah on Mancos Shale badland slopes averaging 35 degrees. More intensive studies were carried out over a 10‐year period on slopes averaging 40 degrees. On the 35 degree slope the average rate of movement was 2.71 cm yr−1.On the 40 degree slopes, rates varied from 3.14 to 5.94 cm yr−1.Individual rates of movement varied widely, but average movement of a given line was consistent. No statistical differences in rates of movement were found between north‐ and south‐facing slopes.About two‐thirds of the total movement occurred during the winter/spring period; episodes of rapid movement coincided with years in which storms deposited at least 0.6 cm of precipitation per day for at least two consecutive days. Downslope rotation of nails indicates that creep involves only the top few centimeters of soil.

Labor outcome of juvenile primiparae in a population with a high incidence of contracted pelvis

Labor outcome of primiparae less than 17 years was compared with non-juvenile primiparae in a population with a high incidence of contracted pelvis. Juvenile primiparae were referred to hospital on the basis of age, whereas non-juveniles were referred for an obstetric complication. There was no statistical difference in rates of cesarean section, Ventouse, operative delivery, low birth weight, or perinatal mortality between 538 juveniles and 5294 older “high risk” mothers. Symphysiotomy rates were actually higher in the juveniles (12.6% vs. 9.7%, P < 0.05). These data support the practice of hospital referral for juvenile African women in labor.

Closed recirculatory spinal subarachnoid perfusion for determining CSF dynamics.

A new method for determining the rates of cerebrospinal fluid (CSF) production under nonsteady-state conditions, namely, closed recirculatory spinal subarachnoid perfusion, was used to determine the effect of enflurane on the rate of CSF production in dogs. Considerable variability in results was observed such that there was no statistical difference in rates of production among animals that received enflurane 2.2%, enflurane 2.2% and nitrous oxide 60% to 70%, enflurane 3.2% and nitrous oxide 60% to 70%, or nitrous oxide 60% to 70% (controls). Possible sources of variability were sought in additional studies using a modification of the new method, and in an in vitro model. The results were compared to those obtained using an established method for determining rates of CSF production, namely, open ventriculocisternal perfusion. It was concluded that the sources of variability in the closed recirculatory method relate in part to adherence of the fluorescein-conjugated albumin tracer to glass and other surfaces, and to uneven flow and distribution of the tracer in the recirculatory system. When the open ventriculocisternal perfusion method was used, consistent results were obtained, demonstrating that CSF production rate increased significantly in animals that received enflurane. The authors conclude that the new closed recirculatory method is less reliable than the classical open perfusion method.