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991.
992.
The overall goal of this paper is to provide for the first time a comprehensive critical review of the literature on contraceptive failure in developed countries, primarily the United States. The first two sections of our paper lay the groundwork for a critical assessment of the extensive body of studies on this subject, by systematically exploring the concepts and measurement of contraceptive efficacy and the methodological pitfalls that snare many investigators and compromise their results. The next two sections focus on results in the literature. First we provide a method-by-method critique of the available studies and then we summarize our conclusions in a single table that provides efficacy information necessary for women and couples to make an informed choice of a method of contraception. We close with a set of substantive observations and also a set of methodological recommendations intended to improve the quality and comparability of findings from future research. 相似文献
993.
994.
Factitious illness in children is a phenomenon that results in adverse consequences for the child. Munchausen by proxy is a factitious disorder, first described by Meadow (1977), in which a parent induces or creates the appearance of illness in the child. This article highlights the importance of social work skills in the identification and management of this syndrome, and proposes a format for decision making at various points in the process. 相似文献
995.
996.
Descriptive and comparative analysis of geometrical properties of neuronal tree structures 总被引:1,自引:0,他引:1
The morphology of neurons is an important factor for the identification and the study of the changes that occur in the nervous system during development or as a result of disease or an experimental treatment. A number of methods to describe the topological aspects of neuronal morphology is discussed. Furthermore it is illustrated how different groups of neurons can be compared. Although both topological and metrical aspects are considered in the comparative sections emphasis is put on counting instead of measuring. Our intention is to present quick and easy methods that are applicable to camera lucida drawings. 相似文献
997.
Hirschsprung's disease in young adults 总被引:3,自引:0,他引:3
Hirschsprung's disease is rarely seen in the young adult, and presents unique problems in management because of the massive dilatation and hypertrophy that occur proximal to the aganglionic rectum or the rectosigmoid colon. The diagnosis, which may be suspected by barium enema, is confirmed by suction or full-thickness biopsy of the rectum that may be complemented by anal manometry. Based on our experience with eight patients, a two-stage surgical reconstruction is recommended, with a preliminary sigmoid colostomy through the normally innervated colon and an associated defunctionalized stoma constituting the initial operation. The distal colonic stoma permits cleansing of the caudal colon while the normally innervated proximal colon reverts to near normal caliber, usually within 2 to 6 months. This approach is in accord with the recommendation of Fairgrieve. Reconstruction using a Duhamel or Soave procedure has given good results. The Duhamel procedure seems preferable when a considerable discrepancy remains between the ganglionic and aganglionic segments of rectum. 相似文献
998.
999.
D J Dandy 《The Orthopedic clinics of North America》1986,17(2):221-229
Arthroscopy plays an important role in diagnosis in the management of anterior knee pain and may be used for treating the underlying pathology. 相似文献
1000.
We examined several possible causes for the high incidence of poor sensory acuity in the limbs of 176 patients with moderate to severe peripheral vascular insufficiency. We investigated the relationships of diabetes, alcoholism, and smoking, as well as the severity of peripheral vascular disease, to the integrity of basic sensory modalities such as two-point discrimination and perception of light touch. The presence or absence of diabetes exerted the strongest effect on peripheral sensation. In patients who did not have diabetes, sensation in the limbs was most strongly affected by whether the patient was an alcoholic. Smoking did not have a significant effect on limb sensation. Among nondiabetic, nonalcoholic patients, there was a weak residual effect related to the severity of the peripheral vascular insufficiency. Even among these patients, however, systemic factors predominated in determining the loss of sensation. We also examined the extent to which loss of sensation might be related to the development of ulcers. Among patients who were not diabetic, there was a highly significant relationship between loss of sensation and the presence of limb ulceration. Surprisingly, however, there was no discernable relationship between the presence of ulcers in diabetic patients and the degree of loss of peripheral sensation. This result suggests that a large percentage of ulcers seen in diabetic patients are not of neurogenic origin. 相似文献