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11.
糖尿病大鼠红细胞膜Band3蛋白的变化   总被引:1,自引:0,他引:1  
目的:研究糖尿病时红细胞膜蛋白的变化。方法:注射STX诱发大鼠糖尿病,通过SDS-PAGE对糖尿病3个月大鼠红细胞膜蛋白进行电泳分析。结果:糖尿病大鼠红细胞膜Band3蛋白含量明显低于正常对照大鼠。结论:由于Band3蛋白是红细胞膜蛋白的主要成分,参与红细胞变形、物质通透等多方面的功能活动,其变化可能会直接影响红细胞的结构和功能,因此,糖尿病时Band3蛋白的变化值得进一步深入研究。  相似文献   
12.
The present paper deals with a detailed analysis of cortical projections from the magnocellular basal nucleus (MBN) and horizontal limb of the diagonal band of Broca (HDB) in the rat. The MBN and HDB were injected iontophoretically with the anterograde tracer Phaseolus vulgaris leucoagglutinin (PHA-L). After immunocytochemical visualization of labeled efferents, the distribution of projections over the cortical mantle, olfactory regions and amygdala were studied by light microscopy. Based on differences in cortical projection patterns, the MBN was subdivided in anterior, intermediate and posterior portions (MBNa, MBNi and MBNp). All subdivisions maintain neocortical projections and are subject to an anterior to posterior topographic arrangement. In the overall pattern, however, the frontal cortex is the chief target. Furthermore, all MBN parts project to various regions of meso- and allocortex, which are progressively more dense when the tracer injection is more anteriorly placed. The most conspicuous finding, however, was a ventrolateral to dorsomedial cortical projection pattern as the PHA-L injection site moved from posterior to anterior. Thus, the posterior MBN projects predominantly to lateral neo- and mesocortex while the anterior MBN sends more fibers to the medial cortical regions. Furthermore, the MBNa is a source of considerable afferent input to the olfactory nuclei and as such should be regarded as a transition to the HDB. The HDB, apart from projecting densely to olfactory bulb and related nuclei, maintains a substantial output to the medial prefrontal cortical regions and entorhinal cortex, as well. Comparison of young vs aged cases indicate that aging does not appear to have a profound influence on cortical innervation patterns, at least as studied with the PHA-L method.  相似文献   
13.
目的:评价张力带固定法治疗锁骨远端骨折的临床效果。方法:对20例锁骨远端骨折行切开复位后张力带固定法治疗。术后随诊分析。结果:所有骨折均在半年内愈合。患侧肩关节功能恢复良好。无一例出现伤口感染。结论:张力带固定治疗锁骨远端骨折是一种简单可靠的手术方法。  相似文献   
14.
15.
关节镜下经皮张力带钢丝固定治疗髌骨骨折   总被引:1,自引:0,他引:1  
目的探索髌骨骨折错位在关节镜下复位、内固定的新方法。方法对56例新鲜闭合性横断型髌骨骨折病例,在关节镜下冲洗关节腔积血,清除骨折断端凝血块,去除小的骨碎片,进行髌骨复位,直接观察关节面复位对合情况。应用胥氏张力带钢丝固定原理,经皮穿入克氏针及钢丝,针孔做1cm小切口,完成内固定。结果术后2周绝大部分患者屈膝可达90°以上,骨折在6~10周达到临床愈合,出现针尾触痛者8例,克氏针松动上移2例,无钢丝断裂及脱落。治疗效果按膝关节损伤患者的功能评定法,优良率为96.4%。结论本术式两枚克氏针各有一根钢丝固定,在关节镜导引下,经皮穿针钢丝固定,不会因两根针位置不对称而产生扭距。操作方法简便、有效,有利于术后早期功能锻炼,为髌骨骨折提供了一种新的手术方法。  相似文献   
16.
Abstract: A patient who represented acute hemolytic crisis was studied. Analysis of the erythrocyte membrane proteins by SDS-PAGE revealed a deficiency of band 4.2. In the family, the sister of the patient who had been clinically normal was also shown to be deficient in band 4.2. Binding studies showed that the propositus' membranes were able to bind normal band 4.2 protein as much as control. It was suggested that the binding sites for the protein were prepared on the membrane. We analyzed the band 4.2 cDNA of the propositus and detected a mutation that changes a codon for alanine to one for threonine at residue 142. Band 4.2 exon III of genomic DNA which included the mutation site was amplified and sequenced directly in the family members, and it was revealed that only the homozygotes of the mutation allele manifested band 4.2 deficiency and the parents, who were heterozygotes, showed normal amounts of band 4.2. Recently, the same mutation was reported as Protein 4.2NIPPON in another 4 cases (Bouhassira et al. Blood 1992: 79: 1846–1854). This study supports the hypothesis that this mutation is the pathogenetic cause of band 4.2 deficiency and not a polymorphism.  相似文献   
17.
The distribution patterns of choline acetyltransferase (CAT), as a marker for cholinergic neurons, and Calbindin-D28k (CaBP) immunoreactivities in the forebrain basal ganglia of the Japanese monkeyMacaca fuscata were compared. Similar distribution patterns of CAT and CaBP immunoreactivities were found in the medial septal nucleus (MS) and the nucleus of the diagonal band of Broca (DBB). Double-labeling fluorescence immunocytochemistry revealed that most, but not all, cholinergic neurons were CaBP-immunoreactive in the MS and DBB. The results suggest that CaBP may play a role in the septohippocampal cholinergic neuron system of the monkey.  相似文献   
18.
Autoimmune haemolytic anaemia (AIHA) can be induced in mice by repeated injections with rat red blood cells (RBC). Here we describe the identification of rat and murine RBC antigens recognized by T-cells from mice with this disease. Splenic T-cells from mice with AIHA proliferated in response to multiple murine RBC membrane components, each of which is recognized by rat RBC induced autoantibodies. Thus, there were responses to murine autoantigen fractions that correspond in apparent molecular mass with the anion channel Band 3, with spectrin from the membrane skeleton and with the high and low molecular mass glycophorins, and the equivalent fractions from rat RBC also stimulated proliferation by T-cells. It was confirmed that purified Band 3 from murine and rat RBC also elicited responses. In contrast with the results in AIHA, T-cells from healthy control mice failed to respond to the antigens from either species, with the exception of proliferation induced by murine spectrin in one experiment and weak responses elicited by rat Band 3. It is suggested that T-cells activated by multiple cross-reactions between rat and murine RBC proteins, and by epitope spreading, are necessary to drive autoantibody production in this model of AIHA.  相似文献   
19.
用免疫细胞化学PAP法,对成年大白鼠隔-斜带(S-DB)复合体中,含小白蛋白(PV)神经元的分布和形态学进行了研究,并与含胆碱乙酚化酶(ChAT)神经元的观察进行了比较。含PV神经元主要位于内侧隔核(MS)、斜带垂直支(vDB)和斜带水平支(hDB)。PV免疫反应神经元的形状和大小在S-DB复合体的各个核区或同一核区都不相同,表明这些神经元具有多样的形态学特征。在整个S-DB复合体中,含PV和含ChAT神经元的比例,各占PV和ChAT阳性反应细胞总数的47/和53/,在MS、vDB和hDB中,PV免疫反应神经元的比例分别为38%、54%和59.5%,其余为含ChAT的胆碱能神经元。  相似文献   
20.
成人房室束、假腱索和节制索的亚显微构造   总被引:4,自引:0,他引:4  
本文研究了两例成人房室束、假腱索和节制索的亚显微构造。结果表明,在成人房室束、假腱索和节制索中均可见浦肯野细胞,细胞宽而短,肌原纤维和组成肌原纤维的肌丝均较少;核多为一个,核周肌浆中有大量线粒体,核附近偶见高尔基复合体;肌浆中亦见肌浆网、糖原颗粒和溶酶体等。另外在房室束中,还可见一般心肌细胞和介于浦肯野细胞与一般心肌细胞之间的过渡细胞(或称移行细胞)。胶原纤维和毛细血管等分布在几种肌细胞之间。房室束浦肯野细胞的端与端之间有不甚典型的闰盘。相邻并列的过渡细胞之间见两种连接形式:一种是一个过渡细胞的分支与另一个过渡细胞的外侧面形成闰盘样连接;另一种是并列相邻的两个过渡细胞,以短的分支几乎呈直角互相连接。  相似文献   
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