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1.
Chitambar  CR; Zivkovic  Z 《Blood》1989,74(2):602-608
Information regarding transferrin (Tf) receptor degradation is largely incomplete. HL60 cells were shown to release to their growth medium a Tf-binding protein which could be immunoprecipitated by anti-Tf receptor monoclonal antibodies (MoAbs) B3/25 and OKT9. Soluble Tf receptor was detected in the medium within one hour of replating of cells, and its release was inhibited at 4 degrees C. The affinity of Tf for the soluble receptor released by cells (kd = 2.3 x 10(-10) mol/L) was slightly lower than its affinity for the detergent-solubilized cellular receptor (kd = 1.2 x 10(-10) mol/L). 125I-Tf internalized and released by cells subsequently bound to Tf receptor released by the same cells, and soluble Tf receptor in the conditioned medium (CM) inhibited 125I-Tf binding to intact cells. The soluble Tf receptor isolated from the CM was smaller (78,000 daltons) than the cell surface receptor (94,000 daltons) when analyzed by gel electrophoresis under reducing conditions. Isolated cell membranes readily released soluble receptor; however, this release could be blocked by protease inhibitors. The soluble Tf receptor may represent the extracytoplasmic domain of the cellular Tf receptor released from the surface of HL60 cells through proteolytic cleavage by a membrane-based protease.  相似文献   
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Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
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There is increasing evidence that immunological mechanisms play a role in the pathogenesis and pathophysiology of endometriosis. It was therefore of interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal fluid and peripheral blood of women undergoing laparoscopic procedures. The presence and concentrations of IL-8 in relation to endometriosis, infertility and abdominal pain were evaluated. Samples of peritoneal fluid (n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive patients undergoing laparoscopic surgery for various gynaecological indications (abdominal pain, infertility, sterilization). IL-8 was present in the peritoneal fluid of most women (87%). The concentration of IL-8 in the peritoneal fluid was higher in women with endometriosis compared to women without (P = 0.02). This difference was more pronounced in early (stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal fluid were also higher in women with early endometriosis compared to women with later stages of the disease (P = 0.003). Peripheral blood concentrations did not correlate with peritoneal fluid concentrations of IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an important factor that may contribute to the pathogenesis of endometriosis possibly by promoting neovascularization. This information can be a guide in the development of new therapeutic approaches for the treatment of endometriosis.   相似文献   
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The distribution of cardiac output was determined by 15 m radioactive microspheres in all the major organs of spontaneous, DOCA/NaCl and one kidney Goldblatt hypertensive rats and compared to normotensive Wistar rats. Although there were alterations in cardiac output distribution which were characteristic of each model of hypertension significant changes were common to all three were an increased distribution to skeletal muscle with decreases to the lungs, spleen and hepatosplanchnic tissues. The results suggest that alterations in peripheral resistance induced by hypertension are of unequal importance in the different vascular beds with certain vascular resistance changes occurring irrespective of the origin of the hypertension.Abbreviations used in this paper SHR spontaneously hypertensive rats - DOCA deoxycorticosterone acetate Supported by I.C.I. Pharmaceutical Ldt and the Mersey Regional Health Authority (Research Schemes No. 338).  相似文献   
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Summary In order to determine whether or not glucagon released from the pancreas might have local vascular effects, the actions upon regional haemodynamics in the anaesthetised rat of two doses of glucagon (2 and 10 g kg–1 min–1) infused intrasplenically (and thus into the portal vein) were compared with those of a single dose (2 g kg–1 min–1) infused i. v. Infusion of glucagon i. v. produced a significantly increased heart rate (by 6%) and cardiac output (by 23%) in the experimental animals compared to those receiving saline by the same route. Total peripheral resistance fell by 24%. A greater proportion of the cardiac output passed to the coronary and renal vascular beds and blood flow was increased in the spleen, testes, pectoral skeletal muscle, stomach and small intestine as well as the heart and kidneys.The lower dose infused intrasplenically had no significant effect on cardiac output or total peripheral resistance but significantly increased the proportion of cardiac output passing both to the stomach and the small intestine such that the percentage of cardiac output flowing through the portal vein increased from 19.1 ± 1.1% to 23.8 ± 1.7%.Intrasplenic infusion of 10 g kg–1 min–1 significantly increased cardiac output (by 29%) but reduced total peripheral resistance by 37%. Greater fractions of the cardiac output were received by the spleen, small intestine and epididymides. Blood flow was increased in these organs and the skin, kidneys, stomach, large intestine and the mesentery.It is concluded that pharmacologically effective amounts of glucagon only passed into the systemic circulation with the higher dose infused intrasplenically. Thus the redistribution of cardiac output in favour of the splanchnic bed with the lower dose of glucagon infused into the portal region is most likely the result of local mechanisms rather than a direct effect of the hormone on the inflow vasculature resulting from recirculation. Send offprint requests to C. R. Hiley at the above address  相似文献   
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0 引言  1 992 - 0 5~ 1 999- 0 5我科收治慢性硬膜下血肿 (CS-DH) 1 6 8例 ,其中 1 6 4例经颅骨钻孔冲洗引流术治疗 ,4例保守治疗 ,结果 1 6 5例治愈 ,3例死亡 .结论 :CSDH的诊断主要依靠 CT检查 ,手术简单 ,防止并发症可改善预后 .1 临床资料 男 1 6 3例 ,女 5例 ,年龄 32~ 79岁 ,平均 5 4岁 .有明确的外伤史 1 4 5例 (86 .3% ) ,原因不明 2 3例(1 3.7% ) ,病程 3wk~ 6 a.头昏、头痛、呕吐 1 1 6例 ,肢体运动障碍 6 8例 ,智力及精神障碍 46例 ,语言障碍 1 0例 ,感觉障碍2 1例 ,排尿障碍 5例 ,癫痫 3例 ,视乳头水肿 92例 ,锥体…  相似文献   
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