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1.
Knee prostheses with metal backing of the polyethylene tibial component are nowadays used almost universally. Eight cases of fracture of the metal tray are reported in the literature. We present a case in which the failure could be expected because of improper design of the tibial tray. 相似文献
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Fine-needle aspiration biopsy, used extensively for evaluating head and neck masses in adults, also provides an excellent minimally invasive means of evaluating infants with neck masses and torticollis. Three cases of torticollis involving infants are presented. In each case, fine-needle aspiration revealed a benign fibrous lesion, ruling out malignancy. The remaining cytologic differential diagnosis between infantile fibromatosis, fibromatosis colli, and calcifying aponeurotic fibrosis is discussed, with mention of the possible causes of and treatment for congenital torticollis. We conclude that fine-needle aspiration provides a fast and accurate diagnosis of neck masses in infants who have congenital torticollis, thereby avoiding surgical procedures in this very young age group. 相似文献
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Spread of excitation in the smooth muscle of the rat portal vein 总被引:3,自引:0,他引:3
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Ljung RC 《Thrombosis and haemostasis》1999,82(2):525-530
To summarize, prophylactic treatment of hemophilia begun at an early age has been gaining acceptance as the optimal therapeutic option in an increasing number of hemophilia centers in the developed world in recent years. In all too many parts of the world, however, this option must be viewed as a long-range goal in hemophilia care, since national economic resources are insufficient for regular prophylactic treatment to be feasible at the moment. The future development of prophylaxis seems to be focused on three different areas. First, research has focused on improving the cost-effectiveness of the current model by testing daily, frequent injections using novel devices for venous access or continuous infusion with portable or implantable mini-pumps and administration of bio-engineered concentrates with a prolonged half-life at a reduced price. Secondly, a break-through in gene therapy, which will enable us to introduce a gene producing an amount of clotting factor sufficient to provide a continuous prophylactic concentration in the blood. Finally, the most mind-challenging option makes most of the discussion in this chapter obsolete and focuses on the development of an oral compound, peptide, or peptidomimetic agent with the capacity to activate the coagulation cascade in a controllable way. 相似文献
6.
Mice in experimental delay of implantation were injected intravenously with 75 g · g–1 body weight of lead chloride, corresponding to a dose of lead of about 56 g · g–1 body weight. Delay of implantation was obtained by ovariectomy 3 days after mating followed by a depot dose of progesterone every fifth day. Electron microscopy showed that the uterine lumen, which was closed in control mice, was opened in lead-injected mice. This morphology suggested that lead caused an increase in uterine secretion. X-ray microanalysis of pyroantimonate precipitates in the uterine epithelium of injected mice demonstrated lead in the precipitates, suggesting that lead could have a direct effect on the function of the uterine epithelium and that lead also could be secreted into the uterine lumen and affect the blastocysts. 相似文献
7.
Diagnostic findings from testis fine needle aspiration mapping in obstructed and nonobstructed azoospermic men 总被引:3,自引:0,他引:3
PURPOSE: Although helpful for defining extratesticular obstruction, the testis biopsy offers limited information on nonobstructive azoospermic testes. Guided by diagnostic biopsies, testis sperm extraction procedures fail in 25% to 50% of patients with nonobstructive azoospermia, largely because it is clinically difficult to know where sperm are located. To provide a more complete assessment of spermatogenesis in nonobstructive azoospermic patients and to simplify the confirmation of sperm production in men with obstruction, we use a systematic, fine needle aspiration "mapping" procedure. We summarize the diagnostic findings in a series of azoospermic men. MATERIALS AND METHODS: From 118 azoospermic infertile men (22 with obstructed and 96 with nonobstructed azoospermia) fine needle aspiration data were used to generate location specific, sperm frequency maps for obstructed and nonobstructive azoospermic testes to determine if "sperm rich" locations existed. RESULTS: Fine needle aspiration map analysis revealed that all aspiration locations from obstructed cases showed sperm. In men with nonobstructive azoospermia, sperm was identified in the right testis in 134 of 652 (20.5%) and in the left testis in 151 of 716 (21.1%) separate aspirations. Rates of sperm detection among various intratesticular sites were not statistically different. In 27.1% of cases the fine needle aspiration map found sperm in men with sperm negative biopsies. The likelihood of heterogeneity in fine needle aspiration sperm findings was 25% within individual nonobstructive azoospermic testes and 19.2% between testis sides. At post-procedure followup of 88 patients (74%), no clinical or surgical complications were observed. CONCLUSIONS: Testis fine needle aspiration mapping is a simple, reliable and informative diagnostic tool in the evaluation of azoospermic infertile men. 相似文献
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Carrier detection in hemophilia A: a cooperative international study. I. The carrier phenotype 总被引:1,自引:0,他引:1
Graham JB; Rizza CR; Chediak J; Mannucci PM; Briet E; Ljung R; Kasper CK; Essien EM; Green PP 《Blood》1986,67(6):1554-1559
Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection. 相似文献