Average Time Lapse Research Articles

Cloward's anterior fusion in the treatment of cervical spinal traumatic injury and degeneration.

The aim of this study was to evaluate the long-term results of Cloward's anterior interbody fusion of the cervical spine and to identify the factors influencing them. The series consisted of 29 patients operated on in 1968--75. The indication for operation was in 12 cases intensive radicular symptoms, not responding to conservative treatment, in connection with considerable degeneration of the corresponding spinal segment only, and in 17 cases instability of the cervical spine caused by traumatic injury followed by dislocation and radicular or medullary symptoms enhancing in spite of conservative treatment by skull traction or collar. Twenty-five patients (86%) attended follow-up after an average time lapse of 6.5 years from operation. The operative result was evaluated considering objective neurological improvement, subjective improvement, present symptoms and working capacity. The operative result was at least fair in 7/11 in the degeneration group and in 12/14 in the traumatic injury group. All fusions were radiologically successful. Adequate correction of a primary flexion deformity of more than 15 degrees was not achieved. Age over 35 years and motor defect preoperatively proved to be statistically significant prognostic factors for a poor operative result in the traumatic injury group. Preoperative sick-leaves and a duration of preoperative symptoms exceeding six months proved to be prognostic factors for a poor result in the degeneration group. In spite of the relatively good clinical results obtained, this study does not justify any conclusions concerning the value of Cloward's procedure compared to other methods of treatment, since no control material was available.

The natural history of chronic otitis media

A retrospective study was made of 200 chronic otitis media patients. Simple chronic otitis media was observed in 76 per cent of cases; the rest were associated with cholesteatoma. In about one third of the patients, the contralateral ear showed some inflammatory middle ear disease as well. The average time lapse between initial symptoms and hospitalization was about 10 years. The events leading to the tympanic perforation were difficult to ascertain, but included probably acute otitis media, possibly external otitis, trauma, and a rather large group (35-40 per cent) of insidious 'essential perforations'. The aetiology of the 'essential perforations' is so far not known, but might be non-inflammatory in nature but related to insufficient middle ear aeration and hypo-pneumatization as well as to what is termed atelectatic ears. The bacteria isolated from chronic otitis media ears (usually gram negative bacteria and staphylococcus aureus) are usually not the types of micro-organisms found in association with any primary or acute otitis media. It is proposed that the bacterial infection encountered in what is termed 'chronic otitis media' is often a secondary infection of a primary perforated tympanic membrane, the perforation originating or persisting in underventilated ears, and having arisen from various causes--some of them as yet unknown.

Upwelling Water as a Factor Influencing Choice of Spawning Sites by Brook Trout (Salvelinus fontinalis)

Abstract Brook trout (Salvelinus fontinalis) generally select areas of upwelling spring water for spawning under natural conditions. When presented with suitable gravel containing an artificially controlled aquifer of about 0.1% the area of a circular tank, female trout selected spawning sites that were either in close proximity to the upwelling water or adjacent to it in 21 of 22 trials. Average time lapse for completion of spawning was about 30 hours. Use of a tank several times larger than 1.9 m2 would probably improve conditions for making more precise observations on discrimination of aquifers under laboratory conditions.

A simple taste test for lacrimal obstruction.

A simple diagnostic test has been developed for the evaluation of the patency of the lacrimal excretory system. A 1% saccharin solution was instilled in the conjunctival cul-de-sac and then tasted by the patient when it reached the oropharynx; this painless and effective test was performed in a study using 100 subjects. The average time lapse between instillation and tasting was 3 ½ minutes. Hopefully, this sweetness-tasting test will be used to identify lacrimal obstruction problems. The test is physiological and reliable. It has proved clinically useful in diagnosing epiphora.

Die zeitliche struktur des Produktionsprozesses und das problem der einkommensverteilung zwischen kapital und arbeit

The Time Structure of the Production Process and the Problem of Income Distribution among Capital and Labour. — By way of introduction two capital theories are contrasted, that which views capital first of all as a produced means of production (Marx, Walras, modern growth theory) and that which takes capital to be the means of bridging the time lapse between expenditure and return (Bohm-Bawerk). The second view, it is true, has been neglected in modern theory, although it is able to deal more easily with a number of important questions. Several such examples are discussed, which would seem to indicate a general tendency towards lengthening the average production period while adapting the interest rate. Examples of this are found in the growing importance both of immaterial capital (organization, education, research) and of the cost-benefit analysis in the public sphere, as well as in the increasing notice that is being taken of external effects of production and consumption. If it can be definitely shown that there is a tendency to lengthen the average time lapse between expenditure and return, this would amount to a shift, in favour of the factor capital, in the functional distribution of income. In an appendix an exact definition is given of what is meant by an average production period, showing also how it can be empirically measured — at least approximatively.

EVALUATION OF ASPIRIN IN TREATMENT OF HEADACHE.

The effectiveness of aspirin in treatment of the common headache has been evaluated in a group of university students employing a blind Latin‐square design. A total of 322 headaches was reported by 100 subjects during the 12 week study. The dosages of aspirin and the per cent of treated headaches showing some degree of relief were: 650 mg. (81 per cent), 325 mg. (68 per cent), 163 mg. (57 per cent), and placebo (57 per cent). Only the percentage associated with the 650 mg. dosage differed significantly from the others. Also, significantly fewer subjects who received the 650 mg. dosage took additional analgesics as allowed by the study. In addition, observations were made concerning the nature and treatment pattern of the headaches. These included their distribution according to time of day of onset (peak 4 to 6 P.M.) and anatomical location (bilateral frontal and generalized most frequent), and measurement of the average time lapse from onset of headache until medication was taken (average 67 minutes).