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41.
42.
Objective:To study the effect of Xuesaitong soft capsule (血塞软胶囊, XST) on liver fibrosis criteria in patients with post-hepatitis fibrosis. Methods: Sixty-four patients with such fibrosis were randomly divided into the treated group and control group. They were treated with XST and Dahuang Zheter treatment. Results: The levels of serum procollagen Ⅲ, hyaluronic acid, collagen Ⅳ, laminin in the two groups were significantly lower (P<0.01) than those before treatment. The differences between the two groups were insignificant (P>0.05). Conclusion: XST could recover liver dysfunction and had anti-liver fibrosis function.  相似文献   
43.
【目的】探讨细胞外基质黏附分子层粘连蛋白(LN)和纤黏连蛋白(FN)与成釉细胞瘤复发和侵袭的关系。【方法】采用免疫组织化学LABC方法检测28例成釉细胞瘤组织中LN和FN的表达。【结果】在28例成釉细胞瘤中,LN和FN在基底膜的阳性表达率分别为46.4%和39.3%,复发性成釉细胞瘤LN和FN在基底膜的阳性表达率明显低于原发性成釉细胞瘤(P〈0.01)。LN和FN的表达形式相似,阳性着色部位均位于基底膜及部分肿瘤细胞的胞浆,在基底膜连续着色的部位,靠近基底膜的肿瘤外周细胞胞浆染色较强,中央内层细胞胞浆染色弱或无,而在基底膜着色缺失的部位,靠近基底膜的肿瘤外周细胞胞浆染色弱或缺失。【结论】LN和FN在基底膜表达缺失与成釉细胞瘤的复发密切相关,可能是成釉细胞瘤局部侵袭的机制之一。  相似文献   
44.
肝病血瘀证与肝功能肝纤维化标志物的关系   总被引:15,自引:0,他引:15  
测定30例肝病血瘀证、32例非血瘀证患者及20例正常人肝功能和血清PCⅢ、LN、HA含量。结果显示HBV感染复制标志血瘀证与非血瘀证均表现较高的阳性率,两者比较无差异。T-BIL升高及A/G降低,血瘀证患者显著高于非血瘀证(P<0.05~0.01)。血瘀证患者血清HA、LN含量明显高于非血瘀证患者及正常人,后两者无显著差异;PCⅢ虽有上述变化趋势,但无统计学意义。提示:ALG下降或倒置及血清HA、LN的含量,可做为慢性肝病血瘀证辨证的客观指标  相似文献   
45.
Abstract: Epidermolysis bullosa (EB) is a group of genodermatoses characterized by fragility and easy blistering of the skin. In the junctional forms of EB (JEB), blisters occur at the level of the lamina lucida, and specific mutations have been detected in the genes encoding different components of the hemidesmosomal-anchoring filament complex. In the non-lethal form of JEB (NL-JEB), mutations in genes encoding two of the polypeptide chains of the anchoring filament protein laminin 5 have recently been described. In this study, we searched for mutations in a family using PCR amplification of exon 14 of LAMB3 , the laminin 5 β3 chain gene, followed by heteroduplex analysis and automated sequencing of the PCR products. We detected a novel combination of mutations in this family, consisting of an out-of frame insertion on one allele, and a splice site mutation on the other allele, representing the first report of a large insertion in LAMB3 , together with a splice site mutation inherited in trans , which result in the NL-JEB phenotype.  相似文献   
46.
An immortalized clonal cell line (AP-16) has been established from glial cultures obtained from neonatal mouse cerebra by multipassages under serum-free conditions. Immunofluorescent experiments showed that AP-16 cells expressed a marker for glial progenitors (A2B5) and did not express markers for oligodendrocytes (galactocerebroside) or mature astrocytes (glial fibrillary acidic protein: GFAP). Treatment with transforming growth factor-β1 (TGF-β1) or fetal calf serum (FCS) for 2 days induced AP-16 cells to differentiate into A2B5-negative, GFAP-positive, phenotypically mature astrocytes. AP-16 cells depended on epidermal growth factor for survival, and their growth was inhibited by FCS. These results indicate that AP-16 cells retained the properties of astrocyte progenitors. An enzyme-linked immunosorbent assay showed that AP-16 cells synthesized fibronectin and laminin, and that the expression of fibronectin was increased by TGF-β1. AP-16 cells should be useful for studying the roles of TGF-β1 in the differentiation of astrocyte progenitors. © 1993 Wiley-Liss, Inc.  相似文献   
47.
Laminin-5 (LN-5) and cyclooxygenase 2 (COX-2) play important roles in many kinds of cancers. Recently, it has been reported that epidermal growth factor receptor [corrected] (EGFR) and/or human epidermal growth factor receptor [corrected] 2 (HER2) expressions are associated with LN-5 and/or COX-2 expressions in a few carcinoma cell lines and human tumor tissue. LN-5, COX-2, EGFR, and HER2 expressions were examined immunohistochemically in 67 patients with urothelial carcinomas (UCs), and associations among these 4 biomarkers and clinicopathologic characteristics were investigated. Patients were classified into transurethral resection group and cystectomy group based on clinical end points, and prognostic significances of increased expressions were evaluated. Overexpression of LN-5, COX-2, EGFR, and HER2 was observed in 16 (23.9%), 34 (50.7%), 42 (62.7%), and 15 (22.4%) of 67 patients, respectively. LN-5 overexpression was associated high-grade (P = .002), invasive (pTa+1 versus pT2-4, P = .011), and nonpapillary (P = .027) UCs. Concerning EGFR and HER2, high-grade (EGFR, P = .0009; HER2, P = .003) and nonpapillary (EGFR, P = .016; HER2, P = .0002) UCs had a significantly higher overexpression rate. UCs penetrating basal membrane (pT1-4) showed significantly higher overexpression rates than pTa UCs on all biomarkers. In transurethral resection group, LN-5 overexpression could be proved as an independent prognostic parameter for intravesical recurrence (P = .007), whereas in cystectomy group, nodal involvement was an independent prognostic parameter for cause-specific survival (P = .025). The current study showed that the 4 biomarkers were associated with aggressive behaviors of UCs. Above all, LN-5 overexpression was considered to play an important role in intravesical recurrence of superficial UCs.  相似文献   
48.
The 67-kDa LR protein was originally discovered as a non-integrin laminin receptor. Several more recent in vitro studies demonstrated the function of 67-kDa LR and its related 'precursor' form 37-kDa LRP as receptors of cellular prion protein and their implication in abnormal prion protein propagation in vitro. In addition, expression of both proteins was shown to increase considerably in the brain of scrapie-infected mice and hamsters. While LRP/LR are thus likely to play important roles in neuronal cell adhesion, survival and homeostasis and during pathological disorders, little is known so far about their fine cellular distribution in adult central nervous system. Using immunocytochemistry and western blotting, we show here that the 67-kDa LR is the major receptor form in adult rat brain and spinal cord, expressed within the cytoplasm and at the plasma membrane of most neurons and in a subset of glial cells. The overall distribution of LR correlates well with that reported for laminin-1 but also with brain regions classically associated with prion-related neurodegeneration. In contrast to LR, the 37-kDa LRP form is much less abundant in adult than in postnatal central nervous system. Characterization of a novel antibody allowed us to study the distribution across tissues of cell membrane-associated LRP. Interestingly, this form is almost exclusively found on a subclass of parvalbumin-immunoreactive cortical interneurons known to degenerate during the early stages of Creutzfeldt-Jakob disease. Our demonstration of local differences in the expression of particular LRP/LR isoforms may be a first step towards unraveling their specific molecular interactions.  相似文献   
49.
BACKGROUND: Laminins (Lns) are a family of extracellular matrix glycoproteins located in the basement membrane (BM) of epithelial cells. They exist as heterotrimers composed of an alpha, beta, and gamma chain. Presently, five alpha (alpha1-5), three beta (beta1-3), and three gamma (gamma1-3) chains have been identified with different combinations of these chains resulting in 14 laminin heterotrimers thus far identified (1, 3-5). METHODS: In this study, using immunohistochemistry with chain-specific antibodies, we characterized the expression of the alpha1 (Lns-1/3), alpha3 (Lns 5,6,7), and alpha5 (Lns 10/11) chains in fetal, newborn, infant, prepubertal, and adult benign and malignant prostate glands. RESULTS: In general, alpha1 expression was higher in normal fetal prostate glands and declined by full-term birth, whereas the alpha3 and alpha5 chains remained highly expressed in the adult normal glands. In carcinoma alpha1 (Lns 1/3) and alpha5 (Lns 5,6,7) are lost, whereas alpha5 (Lns 10/11) persists. CONCLUSIONS: Alpha 1 (Lns 1/3) is prominent in BM, but is replaced by a laminin matrix rich in alpha3 (Lns 5,6,7) and alpha5 (Lns 10/11) in benign adult prostate glands. In carcinoma, both alpha1 (Lns-1/3) and alpha3 (Lns 5,6,7) are not expressed with persistence of a BM rich in alpha5 (Lns 10/11).  相似文献   
50.
Dystroglycan (DG) is a single receptor that binds to multiple basement membrane proteins and forms a transmembrane link to the actin cytoskeleton. It was first isolated as a component of the dystrophin-glycoprotein complex, which plays a role in the maintenance of muscle cell integrity and is defective in many muscular dystrophies. Although studied most extensively in muscle tissues, DG is present at most cell-basement membrane interfaces, and only recently has investigation of DG functions in nonmuscle cells gained momentum. Information emerging from recent studies in epithelial cells is implicating DG in a wide range of critical cell responses to the basement membrane, ranging from organization of tissue architecture to cell survival. Moreover, DG functions appear to be frequently absent in carcinoma cells, implicating its loss in cancer progression. Although many questions remain as to its precise role in mammary tissue, DG is emerging as a potentially important player in mammary gland function.  相似文献   
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