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A regional anaesthetic technique is described using a blind anatomical approach to the obturator nerve and nerve to quadratus femoris, as a means of alleviating the disabling pain of chronic osteoarthritis of the hip, when arthroplasty is not available. 相似文献
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DR Grow S Oehninger HJ Seltman JP Toner RJ Swanson TF Kruger SJ Muasher 《Canadian Metallurgical Quarterly》1994,62(3):559-567
OBJECTIVE: To investigate the predictive value of sperm morphology assessed by strict criteria on IVF outcome. DESIGN: Retrospective analysis of all IVF cycles (January 1987 to December 1992). MAIN OUTCOME MEASURES: All patients were assigned to one of three groups based on sperm morphology: P-pattern (< 4% normal forms), G-pattern (4% to 14% normal forms), and N-pattern (> 14% normal forms). Morphology pattern was related to other semen characteristics and IVF outcome. RESULTS: Despite corrective measures at oocyte insemination, the fertilization rate was significantly different among the three morphology groups, P < G < N. N-pattern sperm produced a mean fertilization rate over 85% regardless of low motility or concentration. In a cohort study, P-pattern cycles produced a lower implantation rate and lower ongoing pregnancy rate, independent of the lower fertilization rate. CONCLUSIONS: Strict morphology is an excellent biomarker of sperm fertilizing capacity, independent of motility and concentration. P-pattern sperm may denote a poorer prognosis for establishing a pregnancy, even after a satisfactory fertilization rate is achieved. 相似文献
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RAP offers a complex and often confusing array of symptoms and diagnostic possibilities. This may be due to its unique age of presentation, its inherent somatic and cognitive developmental issues, or the physiology of abdominal pain itself. A careful examination of the historic and physical findings should produce a therapeutic plan that addresses somatic, psychological, and environmental aspects of the child. This process will avoid overly simplistic and premature misdiagnosis or potentially unnecessary investigations that convey a sense of disinterest, haste, and disbelief in the problem. The successful management of RAP lies in the recognition that serious underlying disease frequently is not present and that time usually is on our side. It is the process of continued and thoughtful evaluation and reassurance over time that counts. 相似文献
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Due to its strategic anatomical position, the endothelium is constantly exposed to the different risk factors for atherosclerosis. During the last decade it has become clear that hypertension profoundly affects endothelial function. Depending on the form of hypertension, endothelium-dependent relaxation is impaired in most vascular beds. In spontaneous hypertension, the production of nitric oxide, which in endothelial cells is formed from L-arginine via the constitutively expressed enzyme endothelial nitric oxide synthase, represents the main mediator of endothelium-dependent vasodilation and seems to be enhanced. On the other hand, the release of endothelium-dependent contracting factors such as prostaglandin H2 and thromboxane A2 have been demonstrated in this model of hypertension. Similar results have been obtained in the forearm circulation of patients with essential hypertension. In contrast, in models of salt-sensitive hypertension no release of vasoconstrictor prostanoids can be found indicating a decreased production of nitric oxide. Thus, in spontaneous hypertension an increased production of nitric oxide seems to occur, which is ineffective due to either the simultaneous release of endothelium-dependent vasoconstrictors and/or inactivation of nitric oxide, or due to anatomical changes such as hypertension-induced intimal thickness which inhibits its action on vascular smooth muscle cells. In summary, in hypertension, endothelium-dependent vasodilation is blunted and the endothelial L-arginine nitric oxide pathway is altered. These changes seem to represent a consequence rather than a cause of hypertension. 相似文献
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