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排序方式: 共有1526条查询结果,搜索用时 15 毫秒
1.
对57例内膜刮出组织和宫内流出组织均未检出绒毛膜绒毛。用抗血清标记绒毛滋养层的人绒毛膜促性腺激素(HCG)、人胎盘催乳素(HPL)和妊娠特异糖蛋白(SPI),结果18例被标记,37例未被标记。临床证明未被标记的37例为异位妊娠。表明用激素标记子宫内膜可提高异位妊娠的诊断率。 相似文献
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In 44 patients with one or more calculi in the upper two-thirds of the ureter, single-stage percutaneous nephrolithotomy was performed through a middle or upper calyceal nephrostomy after cystoscopic placement of an occlusion balloon catheter distal to the calculus; in 42, the procedure was successful. The occlusion balloon catheter permitted retrograde opacification of all systems for enhanced renal puncture. In the last 30 patients an attempt was made either to push the calculus upward mechanically or to flush it upward into the renal pelvis with carbon dioxide or dilute contrast material. This was successful in 24 of these patients. Prior overnight occlusion of the ureter by means of ureteral dilatation further facilitates dislodgment of the calculus, which was successful in 12 of 13 patients. 相似文献
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Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
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C. Moyer D. Allen A. Basabe R.R. Maronpot A. Nyska 《Experimental and toxicologic pathology》2004,55(6):455-465
Riddelliine alters hepatocellular and endothelial cell kinetics and function including stimulating an increase in hepatocytic vascular endothelial growth factor (VEGF) in the absence of increased serological levels of VEGF (Nyska etal. 2002). The objective of this study was to further assess hepatic VEGF and KDR/flk-1 synthesis and expression by hepatic cells under riddelliine treatment conditions. Forty-two male F344/N rats were dosed by gavage with riddelliine (0, 1.0, and 2.5 mg/kg/day) for 6 weeks. Seven animals/group were sacrificed after 8 consecutive daily doses; remaining rats were terminated after 30 daily doses, excluding weekends. Hepatic tissues were evaluated by immunohistochemistry and in situ hybridization. The results showed that VEGF mRNA expression was observed in control and treated animals; however, qualitative differences were noted. Treated animals exhibited VEGF mRNA in clustered, focal hepatocytes and bile duct epithelium, whereas VEGF mRNA in hepatocytes from vehicle control rats was distributed evenly across all hepatocytes. Results evaluating the distribution of the VEGF cognate receptor, KDR/flk-1 showed that randomly distributed, rare sinusoidal endothelium, including those demonstrating karyomegaly and cytomegaly expressed KDR/flk-1. Phosphorylation of KDR/flk-1 at pTyr996 and pTyr1054/1059, but not pTyr951, was also detected, evidence that endothelial cell KDR/flk-1 was activated. These results suggest that both hepatocytes and endothelial cells are targets of riddelliine-induced injury. We speculate that damage to both populations of cells may lead to dysregulated VEGF synthesis by hepatocytes and activation of KDR/flk-1 by endothelium leading to the induction of sustained endothelial cell proliferation, culminating in the development of hepatic hemangiosarcoma. 相似文献
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The Sendai virus V protein, which is a fusion of the P and V ORFs of the P gene, was characterized with antisera to a portion of the V ORF and compared to the P protein. The only property found in common with P is that V is also highly phosphorylated, and this is so even when these proteins are expressed independently of the other viral proteins. Otherwise, V was not found in virions, was not strongly associated with viral nucleocapsids like P, and anti-V had no effect on viral RNA synthesis in vitro under conditions where anti-P was highly inhibitory. The available evidence suggests that V may play a role in RNA synthesis, but it is not an essential one like that of the P protein. 相似文献
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The pathogenesis of autoimmune vasculitis is poorly understood. Understanding the immunologic mechanisms governing this disease requires precise identification of the cells which comprise the lesion. In this report, we have evaluated tissue sections from MRL/lpr mice from 16 to 45 weeks of age, representing all stages of clinical vasculitis. We demonstrate that basophil myelocytes participate in the evolution of the delayed-type hypersensitivity (DTH) response which initiates and perpetuates autoimmune vasculitis in these mice. These findings raise questions regarding the immunologic mechanisms by which basophils develop in this lesion and the interaction of basophils. VSMCs and lymphocytes in vasculitic angiodestruction. 相似文献
10.
A revised look at the number of uninsured Americans 总被引:1,自引:0,他引:1
M E Moyer 《Health affairs (Project Hope)》1989,8(2):102-110