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1.
PADGEM (GMP140) is a component of Weibel-Palade bodies of human endothelial cells 总被引:65,自引:10,他引:55
PADGEM protein (PADGEM), also known as GMP140, is a platelet alpha- granule membrane protein that is translocated to the external membrane after platelet activation. Although the biosynthesis of this protein was originally thought to be confined to megakaryocytes, the synthesis of PADGEM in endothelial cells was recently demonstrated (McEver et al: Blood 70:1974a, 1987). We now describe the subcellular localization of this protein in endothelial cells. Immunofluorescence staining of permeabilized human umbilical vein endothelial cells with KC4, a well characterized monoclonal antibody to PADGEM, showed positively stained elongated structures similar in distribution and shape to Weibel-Palade bodies. Their identity as Weibel-Palade bodies was confirmed by double label immunofluorescence using KC4 and a polyclonal antiserum to von Willebrand factor (vWf), a protein known to be specifically stored in these organelles. All Weibel-Palade bodies were found to contain PADGEM. In contrast to strong perinuclear staining produced with anti- vWf antibodies, no significant perinuclear staining was obtained with KC4, indicating that relatively little PADGEM is present in the endoplasmic reticulum and in the Golgi apparatus. In endothelial cells treated with secretagogues that stimulate vWf release the elongated structures positive for PADGEM disappeared, further identifying these structures as Weibel-Palade bodies. This observation extends the parallels between Weibel-Palade bodies and alpha-granules and suggests a possible functional association between vWf and PADGEM. 相似文献
2.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
3.
目的:建立骨钙素酶免疫测定方法,并应用于临床检测血清骨钙素。方法:应用了3种检测模式,根据检测灵敏度、剂量反应曲线的形态进行分析,选择出合适的模式进一步应用于临床血清标本的骨钙素检测。结果:所采用的骨钙素单克隆抗体是钙离子依赖型的。固相抗原竞争法适合于临床定量测定骨钙素。最低可测限为1.4μg/L;20μg/L骨钙素样品批内CV=3.98%,批间CV=12.67%。测定正常献血员140名(年龄17-45岁),第5-95百分位点的骨钙素含量,男性为7.5-15.0μg/L女性为7.0-17.5μg/L。70例疑有骨质疏松症患者血清骨钙素含量2.91-30.20μg/L,以第95百分位点的骨钙素含量为cut-off值,升高5例。与进口试剂盒(Novocalcin,USA)相比较,有较好的相关性,r=0.81。结论:固相抗原竞争法酶免疫测定可以灵敏地检测血清中骨钙素含量,有实用价值。 相似文献
4.
胃粘膜上皮“适应性细胞保护”机制防止胃肿瘤发生的作用 总被引:4,自引:0,他引:4
投用致癌剂的对照组其胃肿瘤发生率为22.2%。若同时给予40%Z醇液空腹灌胃,则胃肿瘤发生率达55.9%。如在给乙醇液前15分钟,先给予4%的辣椒煎液灌胃,则胃肿瘤发生率只有20.0%,相近于对照组的水平(后2组差别有极显著意义,P<0.01)。这种给损伤剂(乙醇)之前先给予微刺激剂(辣椒)所产生的胃粘膜的保护作用,是通过促使胃粘膜上皮细胞合成内源性前列腺素(PGs)来实现的,是一种“适应性细胞保护”机制。这种保护胃粘膜的作用可降低胃肿瘤的发生率。 相似文献
5.
本文采用三维位移测量方法,测试10例离体人膝标本的胫股关节三维运动特性。发现屈膝过程中,胫股运动也具有典型的三维运动特点。其中在屈膝初期的30°内,胫骨内旋最明显并伴有胫骨内翻现象,平均内旋8°,内翻6-7mm,膝关节完全伸直时胫股扣锁使膝关节稳定,屈曲时胫股“解锁”使膝关节松弛,具重要的临床意义,同时提示,在解释传统的胫股扣锁现象时不应遗漏伴随发生的胫骨内/外翻现象。 相似文献
6.
周围性面神经损伤患者对侧神经支配的研究 总被引:6,自引:0,他引:6
目的 通过测定面神经损伤患者组及大学生志愿者组面神经各分支对侧神经支配率 ,探讨周围性面肌瘫痪恢复过程中面神经对侧代偿支配的问题。方法 分别测定大学生志愿者 2 2例( 2 2侧 )及 10 8例面神经损伤患者的面神经电图对其对侧神经支配率进行分析其中损伤组又按发病原因不同 ,分为医源性损伤组、Bell氏面瘫组和创伤性损伤组 ,测试损伤支数为Ⅰ支 76支 ,Ⅱ支 81支 ,Ⅲ支 88支 ,Ⅳ支 6 6支。结果 ①损伤组 3组间对侧支配率差异无显著性 (P >0 0 5 ) ;②损伤组Ⅰ、Ⅱ支对侧支配率明显高于志愿者组 (P <0 0 0 1) ;③损伤组Ⅰ支对侧支配率明显高于Ⅱ支(P <0 0 0 1)。结论 面神经损伤后 ,存在对侧神经支配功能增强的表现 相似文献
7.
本文采用新型无机絮凝剂FOLY A-F联合木炭柱处理针织厂印染废水取得较为满意的效果。废水CODCr含量的波动范围为161.8~483.6ppm;固体悬浮物95.5~442ppm;pH8.4~11.6。经本方法处理后,溶液基本上无色透明,固体悬浮物近于0,CODCr含量少于100ppm,CODCr去除率为77.9%。以上四项检测指标均达到国家规定的排放标准。适用于处理中、小型针织厂的废水。 相似文献
8.
膝关节 Q 角变化规律的实验研究 总被引:4,自引:0,他引:4
本研究利用精密三维位移测读仪,研究分析了Q角的变化趋势,以及对髌股关节运动的影响。研究结果表明,Q角是一空间夹角,随屈膝角的增大而增大。力线在平面上的投影所呈的平面夹角Qp也就是通常所指的Q角,在屈膝15°左右达最大,而在90°左右达最小。整个屈膝过程中,QP在5°-15°之间变化,变化幅度达10°左右。 相似文献
9.
Monophasic action potential recordings during acute changes in ventricular loading induced by the Valsalva manoeuvre.
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OBJECTIVE--The strong association between ventricular arrhythmia and ventricular dysfunction is unexplained. This study was designed to investigate a mechanism by which a change in ventricular loading could alter the time course of repolarisation and hence refractoriness. A possible mechanism may be a direct effect of an altered pattern of contraction on ventricular repolarisation and hence refractoriness. This relation has been termed contraction-excitation feedback or mechano-electric feedback. METHODS--Monophasic action potentials were recorded from the left ventricular endocardium as a measure of the time course of local repolarisation. The Valsalva manoeuvre was used to change ventricular loading by increasing the intrathoracic pressure and impeding venous return, and hence reducing ventricular pressure and volume (ventricular unloading). PATIENTS--23 patients undergoing routine cardiac catheterisation procedures: seven with no angiographic evidence of abnormal wall motion or history of myocardial infarction (normal), five with a history of myocardial infarction but with normal wall motion, and 10 with angiographic evidence of abnormal wall motion--with or without previous infarction. One patient was a transplant recipient and was analysed separately. SETTING--Tertiary referral centre for cardiology. RESULTS--In patients with normal ventricles during the unloading phase of the Valsalva manoeuvre (mean (SD)) monophasic action potential duration shortened from 311 (47) ms to 295 (47) ms (p less than 0.001). After release of the forced expiration as venous return was restored the monophasic action potential duration lengthened from 285 (44) ms to 304 (44) ms (p less than 0.0001). In the group with evidence of abnormal wall motion the direction of change of action potential duration during the strain phase was normal in 7/21 observations, abnormal in 6/21, and showed no clear change in 8/21. During the release phase 11/20 observations were normal, five abnormal, and four showed no clear change. In those with myocardial infarction four out of five patients had changes that resembled those with normal ventricles but the changes were less pronounced. There were no differences in any of the three groups between the changes in monophasic action potential duration in patients taking beta blockers and those who were not. The changes in monophasic action potential duration in the transplanted heart resembled those in the group with normal ventricles. Inflections on the repolarisation phase of the monophasic action potential consistent with early afterdepolarisations were seen in three of the patients with abnormal wall motion and in none of those with normal wall motion. CONCLUSIONS--These results are further evidence that changes in ventricular loading influence repolarisation. When wall motion was abnormal the effects on regional endocardial repolarisation were often opposite in direction to those when it was normal. Thus regional differences in wall motion could generate local electrophysiological inhomogeneity which may be relevant to the association of arrhythmia with impaired left ventricular function. 相似文献
10.
Advanced primary breast cancer: assessment at mammography of response to induction chemotherapy 总被引:2,自引:0,他引:2
The response to induction chemotherapy is an important prognostic factor in patients with nonmetastatic, locally advanced breast carcinomas. Assessment at mammography of the response of 60 breast cancers in 59 women was performed between 1974 and 1986. Responses were excellent in 13 tumors, moderate in 34, and poor in 13 (excellent moderate = 78%). Assessment of response of discrete masses in a fatty breast was easiest; assessment of response of tumor areas that were poorly defined-such as a focal area of architectural distortion or mass in dense breast parenchyma-was more difficult. Of 17 patients with excellent pathologic responses-that is, minimal or no residual tumor-15 (88%) had complete responses (no residual tumor) as determined with mammography, physical examination, or both. Mammography provides information complementary to physical examination and is essential in the accurate assessment of the response to chemotherapy of locally advanced breast cancer. 相似文献