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31.
The plasma clotting factors used to treat hemophiliacs who have developed inhibitory antibodies have a shared history of limited clinical safety and utility. To improve on existing bypass factors, we have developed a reversibly acylated form of human plasma factor Xa capable of providing a time-dependent release of procoagulant activity. Factor Xa was treated with p-amidinophenyl p'-anisate to generate anisoyl Xa. The chemical modification of the protein involves acylation of the active site serine residue of factor Xa. Anisoyl Xa deacylated in a time, pH, and temperature-dependent manner. Active factor Xa generated on deacylation of anisoyl Xa exhibited amidolytic and prothrombinase complex activities in in vitro assays, the level being comparable to those of untreated factor Xa. When Anisoyl Xa was infused into rabbits, active factor Xa was generated on deacylation of the acylated enzyme, which shortened the activated partial thromboplastin time (APTT) in a dose-dependent manner. The duration of effect on rabbit APTT could be directly correlated to the level of human plasma factor Xa. Because anisoyl Xa bypasses the "tenase" complex that is compromised in hemophilia A and B and is unaffected by inhibitory antibodies, it has the potential to be used as an effective bypass therapy. 相似文献
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Cytogenetic and histologic correlations in malignant lymphoma 总被引:9,自引:0,他引:9
Koduru PR; Filippa DA; Richardson ME; Jhanwar SC; Chaganti SR; Koziner B; Clarkson BD; Lieberman PH; Chaganti RS 《Blood》1987,69(1):97-102
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change. 相似文献
34.
关于空腹血糖、空腹胰岛素乘积的倒数在流行病学研究中应用的补充说明 总被引:26,自引:0,他引:26
高胰岛素正糖钳夹技术可以测定活体的胰岛素敏感性,但它并不适用于大规模流行病学研究。流行病学研究需要简单的胰岛素抵抗测定法。本文补充报告在空腹血糖(FPG)(75~306mg/dl或4.2~17.1mmol/L)及空腹胰岛素(FIns)(9.7~120mU/L)范围很宽的Pima印第安人群中,正糖钳夹技术测定的胰岛素介导的葡萄糖代谢率(M)与涉及FPG、FIns的多种复合的胰岛素敏感指数的相关性:胰岛素作用指数(IAI)=1/(FPG×FIns)在非糖尿病人群及2型糖尿病人群都与M显著正相关(r>0.7,P=0.0001),而且这两者的相关性强于M与其他指数如FIns或FPG/FIns比值的相关性,也不弱于M与糖负荷后3~5个时间点的血糖、胰岛素曲线下面积乘积的相关性。IAI的五分变量分布情况表明有90.4%的IAI落在所预测的M值五分变量区域或与之相邻的一个五分变量区域之内。1/FPG×FIns虽相对简单但确实与机体的胰岛素敏感性密切相关,它可以做为胰岛素敏感指数在流行病学研究中应用。 相似文献
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Involvement of guanine nucleotide binding proteins in neutrophil activation and priming by GM-CSF 总被引:4,自引:0,他引:4
Pre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte- macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet- activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre- treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor. These results provide the first evidence that a pertussis toxin substrate plays an important mediatory role in the mechanism of action of GM-CSF. 相似文献
39.
Time‐Dependent Changes in QT Dynamics after Initiation and Termination of Paroxysmal Atrial Fibrillation 下载免费PDF全文
40.
Juyu Tang M.D. PH.D. Taolin Fang M.D. PH.D. Dajiang Song M.D. PH.D. Jieyu Liang M.D. PH.D. Fang Yu M.D. PH.D. Congyang Wang 《Microsurgery》2013,33(8):612-619
The deep inferior epigastric artery perforator (DIEP) flap has been a valuable tool in breast reconstruction, but seldom in extremity reconstruction. The aim of this report is to present our experience on the use of the DIEP flap for reconstruction of soft‐tissue defects in the extremities of pediatric patients. From January 2007 to February 2011, 22 consecutive free DIEP flap transfers were performed for reconstruction of complex soft‐tissue defects in the extremities of children with a mean age of 5.7 years old (ranging 2–10 years old). The flap design included transverse, oblique, and irregular DIEP flaps, containing one to three perforators in the flap. The flap size ranged from 7 × 4 cm to 18 × 17 cm. Primary donor‐site closure was accomplished in all of patients. The postoperative course was uneventfully in most of cases. The venous congestion was observed in two cases. One case of venous congestion was caused by flap inset with tension. The other case with venous thrombosis ended with partial loss of the flap after salvage procedure. There was one total flap loss due to the arterial thrombosis. The flap survival rate was 95.5%. The mean follow‐up was 12 months (ranging 6–36 months). All reconstructed extremities had satisfactory aesthetic and functional outcomes except two cases undergoing the secondary debulking procedures. The donor sites healed well in all cases without complications. Our experience showed that the free DIEP flap could be an alternative for reconstruction of soft‐tissue defects in the extremities of children. © 2013 Wiley Periodicals, Inc. Microsurgery 33:612–619, 2013. 相似文献