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91.
Strenuous exercise in women is associated with a high incidence of menstrual dysfunction, including amenorrhoea. Athletic amenorrhoea is most common among long-distance runners and ballet dancers, with a prevalence of up to 66 per cent. It is of hypothalamic origin, the pulsatile release of GnRH (gonadotrophin-releasing hormone) being disturbed during exercise, resulting in low gonadotrophin and oestrogen levels. Accumulated evidence suggests athletic amenorrhoea to be related to energy deficiency or to the eating disorders that are prevalent among athletes. The long-term consequences of amenorrhoea are premature osteoporosis and increased risk of musculoskeletal injury. Elite training in young girls tends to delay pubertal development, resulting in decreased bone mass accumulation and reduced growth potential. 相似文献
92.
The role of practice guidelines in malpractice litigation has been discussed in some theoretical detail. Little information is available, however, on how courts use guidelines or on the effort of state legislatures to explicitly link guideline compliance with malpractice defenses. We review all relevant case law and legislative enactments to shed light on the influence of medical malpractice on guidelines. We also use data from a nationwide survey of malpractice attorneys to supplement our legal analysis. Although guidelines are being used for both inculpatory and exculpatory purposes in common-law litigation (a two-way street), legislatures are interested in applying them only for exculpatory purposes (a one-way street). 相似文献
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95.
The ability of the midbrain reticular formation (MRF) to produce thermogenic responses and to trigger arousal from hibernation was tested during successive quarters of individual hibernation bouts. Golden-mantled ground squirrels (Citellus lateralis) were implanted with bilateral cannula guides into the MRF. Single, bilateral, 1-mul injections of acetylcholine (ACh) at concentrations of 50, 100, or 200 mug/mul were delivered in each quarter of the same bout or in selected quarters of different bouts. The results show that the magnitude of thermogenic responses evoked by ACh stimulation of the MRF was depressed during the early portion of the bout and increased as time in the bout elapsed. Furthermore, the magnitude of responses evoked during hibernation was depressed in comparison to those evoked during euthermia, indicating the influence of inhibition on the responsiveness of the CNS during hibernation. We suggest that during hibernation, a progressive change in responsiveness of the CNS, perhpas focused in the MRF, controls the duration of each hibernation bout. 相似文献
96.
This study was concerned with psychotherapists' evaluations of the outcome of therapy. Staff and resident psychiatrists employed in 23-item questionnaire to rate the seccess of psychotherapy with 85 of their inpatients. These were patients for whom psychotherapy constituted a significant part of the treatment that they received in the hospital. The therapists' responses to the questionnaire items were intercorrelated. The results indicated that a major aspect of a psychotherapist's judgment of the success of treatment-as these judgments usually are employed in current psychotherapy research-is the therapist's affective reaction to the patient, Better-liked patients were viewed as having improved more. However, when the therapists' responses were subjected to factor analysis, independent Improvement and Affection factors emerged. It is suggested that when therapists' ratings of success are used in psychotherapy research they should be treated or refined statistically to minimize potential confounding with their affection for patients. 相似文献
97.
AL Cohen 《Canadian Metallurgical Quarterly》1993,70(6):461-468
Modifying the number, width, depth, and shape of the echelettes in a diffractive bifocal lens will influence the image intensity and quality within the zero, first, and higher order images. By appropriately varying these parameters optimal bifocal lens designs may be achieved. 相似文献
98.
99.
The activities of certain drug metabolizing enzymes have been measured in liver and kidney slice preparations from domesticated birds. Aminopyrine demethylase activity was significantly lower in liver slices from the duck (Aylesbury X Pekin, Khaki-Campbell) than from the rat (Wistar), and in the Aylesbury X Pekin duck lower than in the turkey (Triple 6 FLX), chicken (Brown Leghorn, Rhode Island Red X Light Sussex) and goose (Emden X Doulouse). The microsomal cytochrome P-450 was lower in duck liver (Aylesbury X Pekin) than in rat liver, and the aniline hydroxylase and aminopyrine demethylase activities in a 10,000 g supernatant fraction of liver were lower in duck preparations (Aylesbury X Pekin, Khaki-Campbell) than rat preparations. These observations suggest that the duck is likely to be susceptible to drugs which are metabolized by the cytochrome P-450 containing mono-oxygenases. UDP-Glucuronyl transferase activity was not detectable in liver and kidney slices from two mature geese. This observation was not the outcome of a deficiency of UDP-glucuronic acid, rapid breakdown of glucuronide by beta-glucuronidase or the presence of a substance inhibitory to UDP-glucuronyl transferase. Liver slices from geese, ducks (Aylesbury X Pekin) and chickens contained low UDP-glucuronyl transferase and high sulphate conjugation enzyme activities, whereas the reverse was found in Khaki-Campbell ducks. The activities of UDP-glucuronyl transferase and the sulphate conjugation enzymes were both relatively high in liver slices from the turkey and rat. The kidney contained lower enzyme activities than the liver except in the duck (Aylesbury X Pekin), in which low activities of aminopyrine demethylase and UDP-glucuronyl transferase were present in slices of both organs. In liver slices from chickens and geese the activities of aminopyrine demethylase and the sulphate conjugation enzymes were similar in mature and immature birds, and the activity of UDP-glucuronyl transferase was considerably higher in chicks and goslings than in mature birds of the same species. In the chick the activities of aminopyrine demethylase, UDP-glucuronyl transferase and the sulphate conjugation enzymes were higher in the duodenum than the remainder of the alimentary tract. The activities of these enzymes in pieces of duodenum were as high as those in slices of liver. The inclusion of sulphate in the incubation medium produced a significant increase in the synthesis of p-nitrophenyl sulphate in liver slices and not kidney slices except those from the duck. The kidney slices seemed to produce sufficient sulphate for the reaction of the sulphate conjugation enzymes to proceed at the maximum rate, but the liver slices did not do so. 相似文献
100.
AI Kirienko AR Zubarev AL Kolesnikov VIu Bogachev AV Al'bitski? 《Canadian Metallurgical Quarterly》1993,(6):49-53
A total of 321 patients with suspected acute thrombophlebitis were examined. There were 92 men (30%) and 229 women (70%). For control 15 patients without lower limb vein abnormalities and 19 ones with uncomplicated varicose disease were examined. Ultrasonic examinations using Ultramark-8 (Medata, Sweden) device were carried out in all the patients. Of the 313 cases (in 8 patients the diagnosis of acute thrombophlebitis was not confirmed by ultrasonic examination) ultrasonography results were erroneous in only 6 cases when assessing the proximal borderline of the great subcutaneous femoral vein thrombosis. Hence, the accuracy of duplex scanning in assessment of the proximal border of thrombosis in acute thrombophlebitis was 98.6% in our study. Ultrasonic angio-scanning in patients with superficial thrombophlebitis give reliable and valuable information about the presence, type, and extension of the pathologic process. This helps to optimally solve the therapeutic policy problems and adequately plan surgical intervention. 相似文献