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101.
102.
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.  相似文献   
103.
目的:探讨抑郁症患者大脑半球机能不对称的特点.方法:用集中注意法及两种押韵词,对58名健康被试、115名抑郁症患者进行耳优势测试.结果:1.健康组真词测听未见耳优势,而假词测听呈右耳(左半球)优势.2.抑郁症患者真词测听未见耳优势,而假词测听呈增强的右耳(左半球)优势.3.真词测听,共病焦虑障碍组无耳优势,非共病组有增强的右耳(左半球)优势;假词测听,两组均表现为右耳(左半球)优势,非共病组强于共病组.4.HAMD、HAMA、SCL-90评分与真、假词偏侧指数无相关性.结论:1.健康中国人对真词的加工与认知无耳优势,表明健康中国人在加工真词时需要左右两侧半球的协同参与;对假词的加工与认知则表现出右耳(左半球)优势,表明更为纯粹的言语材料的加工以左半球为主.2.抑郁症患者对汉字词的加工与认知,表现出较健康人强的右耳(左半球)优势.3.共病和非共病焦虑障碍者对汉字词的加工与认知,表现出较健康人强的右耳(左半球)优势,而非共病者较共病者右耳(左半球)优势强.4.患者的言语偏侧化指数与症状严重程度无相关性.5.假词为较为理想的分听材料.  相似文献   
104.
The production and serologic, as well as immunochemical properties of a cytotoxic murine IgG monoclonal antibody (Tü109) that precipitates HLA-class I molecules, are described. In the microcytotoxicity assay Tü109 supernatant was demonstrated on a panel of 424 HLA-ABC, -DR, -DQ, -MT typed normal Caucasian blood donors to define an epitope on HLA-B locus molecules in great association with the supertypic specificity Bw4. Reactivity of supernatant showed MHC linked inheritance of the Tü109 determinant and discriminated the HLA-Bw4/Bw6 associated HLA-B locus split antigens. Weak or lack of binding on lymphocytes from some HLA-Bw4 heterozygous individuals, particularly typing for HLA-Bw44, appeared to be due to qualitative and/or quantitative variations of HLA-B locus molecules on the cell surface. With Tü109 ascites fluid, however, extra-reactivity on all HLA-Bw6+ cells was demonstrated. Preferential binding of supernatant to HLA-Bw4, but reactivity of ascites fluid with HLA-Bw6+ molecules in addition, was furthermore confirmed by IEF analysis of antigens immunoprecipitated with Tü109 from cell lysates. Thus the antibody may help to analyze the evolutionary relationship of the diallelic specificities Bw4 and Bw6.  相似文献   
105.
106.
Modification of the sulfation pattern of heparan sulfate (HS) during organ development is thought to regulate binding and signal transduction of several growth factors. The secreted sulfatases, Sulf1 and Sulf2, desulfate HS on 6-O-positions extracellularly. We show that both sulfatases are expressed in overlapping patterns during embryonic skeletal development. Analysis of compound mutants of Sulf1 and Sulf2 derived from gene trap insertions and targeted null alleles revealed subtle but distinct skeletal malformations including reduced bone length, premature vertebrae ossification and fusions of sternebrae and tail vertebrae. Molecular analysis of endochondral ossification points to a function of Sulf1 and Sulf2 in delaying the differentiation of endochondral bones. Penetrance and severity of the phenotype increased with reduced numbers of functional alleles indicating redundant functions of both sulfatases. The mild skeletal phenotype of double mutants suggests a role for extracellular modification of 6-O-sulfation in fine-tuning rather than regulating the development of skeletal structures.  相似文献   
107.
A 60-year-old Japanese woman was diagnosed at autopsy as having had hereditary hemorrhagic telangiectasia (HHT) associated with systemic hemangiomas. In her repoduction period, premenstrual epistaxis frequently occurred. At the age of 60, the patient died of malignant lymphoma. At autopsy, multiple telangiectatic spots were noted on the face, limbs and trunk. The paraaortic lymph nodes, which were enlarged and irregularly conglomerated, were histologically diagnosed as malignant lymphoma of the diffuse large cell type. Submucosal telangiectatic lesions were found in the gastrointestinal system from the oral cavity to the rectum. Cavernous hemangiomas were present in various visceral organs including the liver, spleen, small and large intestines, rectum, appendix, uterus, and jejunal and colonic mesenteries. There was an arteriovenous fistula in the left lung. Examination of her family pedigree showed that the patient had an autosomal dominant trait of inheritance. The pathogenesis of the systemic visceral hemangiomas observed in this patient was considered to be similar to that of hamartoma.  相似文献   
108.
Subjects of reproductive age at risk of having an affected child with a severe single gene disorder such as Duchenne muscular dystrophy (DMD) or cystic fibrosis (CF) were surveyed to ascertain: their views on genetic counselling and antenatal testing; their knowledge of their risk of having an affected child; and their psychological wellbeing. Questionnaires were posted to 209 individuals at 130 addresses; a 65% response rate was achieved. The majority of those surveyed were under 40 years of age (91%), half of them had received genetic counselling only once and for 47% the first encounter was after the diagnosis of their affected child. Most patients expressed their intention to use prenatal testing. However, less than 50% of those counselled knew their risk of having an affected child. Knowledge of risk was associated with the type of disease in the family (p<0.001) (inheritance of DMD was poorly understood by relevant subjects) and was positively associated with the participant's level of education (p<0.05). We did not detect a significant association between the number of intended children and the risk of having an affected child. In terms of family relations, genetic counselling appears to be beneficial for the nuclear family, the couple and their children, but some counsellees reported a detericration in relations with other relatives. The results indicate that couples at risk of having a child with a severe genetic disorder value the counselling provided, but many of them do not remember important facts in relation to their risk status.  相似文献   
109.
本文采用双盲法对 IDA 和 NIDA学龄儿童各61名进行了认知能力测验及铁治疗前后的动态比较。结果表明:IDA 儿童识记再认、字母匹配反应时、数字扫描记忆和一般推理能力测验成绩较 NIDA 儿童差。经铁治疗的IDA 儿童,注意、短时记忆和心理动作反应速度均有明显提高。但对较高级认知能力的改善不明显。  相似文献   
110.
Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure.  相似文献   
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