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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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Penetrating proximity extremity trauma (PPET) was prospectively studied to clarify the role of routine arteriographic evaluation (AG). Over a 24-month period, 135 patients were identified with 152 injuries from PPET. All patients underwent AG and were randomized to either immediate or delayed timing. There were 27 arteriographic abnormalities from these 152 wounds, of which 16 (10.5%) were in major arteries. One acute arteriovenous fistula underwent immediate surgery. The remaining 15 major vessel injuries were nonoperatively observed, including seven cases of segmental arterial narrowing, six intimal flaps, and two small pseudoaneurysms (one of which enlarged and underwent surgical repair after 10 weeks of followup). Nine of the remaining 14 lesions resolved; two improved and three remained clinically unchanged over a mean followup interval of 2.7 months. Shotgun trauma was the mechanism which carried the greatest risk of significant vascular injury. Although "soft" clinical signs were significantly more predictive of vascular injury following PPET than proximity alone (p less than 0.0005), 50% of all injuries to major arteries did not manifest soft signs. No extremity morbidity resulted from delayed AG or from vascular injury management. We conclude from our study population: 1) the natural history of clinically occult arterial injuries was predominantly benign; 2) AG could be safely delayed up to 24 hours; 3) "soft" signs were not clinically useful predictors of vascular injury; and 4) with the exception of shotgun wounds, AG did not appear to be a cost effective screening modality, since detection of a single vascular injury requiring surgery cost $66,420.00.  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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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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