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101.
目的 通过观察人体内痔不同分期粘膜及血管内皮细胞生长因子(VEGF)及碱性成纤维细胞生长因子(FGF2)的表达,探讨内痔的发生及发展机制。 方法 收集南方医院肛肠科门诊手术切除的Ⅰ、Ⅱ、Ⅲ期内痔标本134例(Ⅰ期42例,Ⅱ期45例,Ⅲ期47例),内痔周围正常肠壁组织40例作为对照,采用HE染色观察组织的病理学变化,采用免疫组织化学方法检测血管内皮细胞VEGF及FGF2的表达。 结果 正常组及Ⅰ期内痔黏膜层被覆上皮完整,未见扩张血管;Ⅱ期内痔黏膜层被覆上皮破坏,黏膜肌层破坏,黏膜层内见新生血管;Ⅲ期内痔黏膜层被覆上皮破坏,见血管管壁增厚迂曲,管腔扩张;与正常粘膜成纤维细胞相比VEGF在粘膜层成纤维细胞表达水平明显升高,并随分期增高而增高(F=883.961,P<0.01),FGF2也存在相同表达(F=656.013,P<0.01);与正常组相比VEGF在血管内皮细胞表达水平明显升高,并随分期增高而增高(F=776.561,P<0.01),FGF2在血管内皮细胞的表达水平存在相同趋势(F=1066.458,P<0.01)。 结论 VEGF及FGF2在内痔的形成过程中具有促进血管内皮细胞和粘膜下成纤维细胞增生的作用,同时可作为内痔发生发展的分子标志物。  相似文献   
102.
目的:探讨不同时间睡眠剥夺(sleep deprivation,SD)对内隐记忆的影响。方法:将32名青年男性随机分为4组:对照组、SD21、SD45和SD69组,每组8名。采用补笔测验和组词测验对4组被试进行测试。结果:SD 后无论知觉启动还是语义启动,启动量降低,并随SD 时间延长而减少。同一组内,两种测验进行比较,除对照组外,其他SD 组两两比较,语义启动的启动量大于知觉启动(P<0.05)。知觉启动中,SD45同SD69 相比无显著差异(P=0.245),其他两两比较差异均有统计学意义(P<0.01);语义启动中,SD21同对照组相比差异无统计学意义(P=0.316),其他两两比较差异均有统计学意义(P<0.01)。结论:SD 后内隐记忆受损,并同SD 时间有关;SD 后语义启动和知觉启动出现分离,知觉启动更受SD 影响。  相似文献   
103.
Proteoglycan-induced arthritis is a murine autoimmune model displaying many similarities to human rheumatoid arthritis and ankylosing spondylitis, as has been documented by clinical, immunological and histopathological studies. Since the onset of arthritis correlates with the serum antibody level to mouse cartilage proteoglycan (PG), it is believed that these autoreactivc antibodies may play crucial roles in the pathological mechanisms of PG-induced arthritis. We have found that fertility in these PG-induced arthritic mice had been reduced but, unlike collagen-induced arthritis, had not been completely lost. Moreover, pregnancy had a beneficial effect upon the clinical symptoms with very little or no influence on scrum antibody levels. Although fertility was retained and arthritic mothers delivered healthy offspring, the birth frequency was significantly less than in non-arthritic age-matched controls. Furthermore, the presence of anti-PG autoantibodies (predominantly IgG1 subclass) transmitted from arthritic mothers to infants transplacentally and by milk during the lactation period did not render these offspring either resistant or more sensitive to subsequent induction of arthritis. Subsequent immunization of infants with ‘arthritogenic’ PG revealed an unaltered susceptibility to arthritis induction.  相似文献   
104.
Oil-induced arthritis is a genetically restricted polyarthritis that develops in the DA rat after injection of the mineral oil Freund's incomplete adjuvant. Here, we investigated the role of the potentially disease-limiting cell populations CD8+ T cells, gammadelta T cells, natural killer (NK) cells and NK T cells in inguinal lymph nodes for the development of this adjuvant-induced arthritis. Flow cytometry analysis before and at disease onset revealed a higher proportion of lymph node T cells expressing NKR-P1 in the disease-resistant LEW.1AV1 compared with the disease-susceptible DA strain, suggesting that NK T cells might be disease protective. However, prophylactic in vivo administration of an anti-NKR-P1 MoAb (clone 10/78) did not consistently affect the disease course. The proportion of CD8+ T cells and the ratio CD4+/CD8+ T cells in inguinal lymph nodes did not differ significantly between DA and LEW.1AV1 rats before or at disease onset. Nevertheless, prophylactic in vivo depletion of CD8+ cells by the OX8 MoAb in the DA strain resulted in an earlier disease onset compared with the control group, demonstrating that CD8+ cells regulate arthritis development. In vivo depletion of gammadelta T cells by the V65 MoAb did not alter the disease course, indicating that the disease-suppressive CD8+ cells are alphabeta T cells or NK cells.  相似文献   
105.
Parameters of NO metabolism in the gingiva were studied during experimental periodontitis accompanied by alloxan diabetes and exogenous hypercholesterolemia. We measured activities of inducible and constitutive NO synthase and concentrations of stable NO end metabolites in rat gingival tissue (total contents of nitrite and nitrate). Under pathological conditions NO metabolism significantly differed from the control. Treatment with mexidol for 14 days significantly decreased activity of inducible NO synthase in the gingiva of experimental animals. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 140, No. 10, pp. 384–386, October, 2005  相似文献   
106.
Summary The distribution of GABA-immunoreactive cell bodies and terminals was studied using an anti-GABA serum during the development of chronic focal epilepsy induced by cobalt deposits onto the motor cortex of the rat. Cell counts of GABA-positive neurons were carried out in the epileptogenic area and correlated with the electrophysiological activity of the cobalt focus. In normal control rats, we identified GABA-immunoreactive somata and processes in the motor agranular cortex; they were multipolar or bipolar but never pyramidal and were present in all layers, especially in layer II. GABA-immunoreactive terminals were widely scattered in the neuropil and surrounded the unlabelled cell bodies. In the cobalt-treated animals, changes in the GABAergic innervation were observed during the development of the epileptic focus: decreases in the GABA-positive cell density and in the number of GABA-positive terminals were present before the onset of epileptic discharges and became more marked during the period of maximal spiking activity; a progressive return to normal values of GABA-positive cell density (except in the deep layers) as well as the reappearance of GABA positive terminals were associated with the extinction of the epileptic syndrome. Our observations suggest that the impaired inhibitory neurotransmission mediated by GABA plays a role in the development of the cobalt-induced epilepsy; moreover the recovery of GABAergic function which occurs during the extinction of the epileptic syndrome might imply a capacity for axonal regeneration of the GABAergic neurons.  相似文献   
107.
We compared the time course of changes in serum levels of circulating immune complexes (CICs) and of IgG antibody after sensitization of albino Lewis and pigmented Lister strain rats with uveitogenic (retinal S-antigen) and non-uveitogenic (ovalbumin) protein antigens of comparable molecular weight. Normal levels of CICs were far lower in Lewis rats in which experimental autoimmune uveoretinitis (EAU) takes the form of a severe panuveitis, than in Lister rats, in which the disease is mild, focal, confined to the posterior segment, and of lower incidence. After sensitization with either S-antigen or ovalbumin, polyethylene-glycol-precipitable CIC (PEG-CIC) peaked and fell as IgG antibody levels rose in both rat strains. However, peak levels of PEG-CIC were lower and subsequent IgG antibody levels were higher in the Lewis strain than in the less susceptible Lister strain. In both strains of rat these linked PEG-CIC/IgG antibody responses occurred earlier after sensitization with uveitogenic (S-) antigen than with ovalbumin, whether or not individual S-antigen-sensitized Lister rats developed EAU. In contrast, complement-binding CIC rose substantially only in those rats of both strains displaying EAU in response to S-antigen and not in response to ovalbumin. We suggest that immune complex (idiotypic) regulation of IgG antibody responses may be more readily perturbed by a pathogenic autoantigen (S-antigen) than by a bland antigen (ovalbumin). We also suggest that differences between the balance of regulatory and pathogenic CIC responses to uveitogenic retinal antigen may underlie or reflect strain differences in susceptibility to and severity of EAU.  相似文献   
108.
Lymphocytes from the cervical lymph nodes of guinea pigs were incubated in medium No. 199 for 24 h in the presence of cortisol in a concentration of 20 or 100 g%. The survival rate of the lymphocytes and their cortisol metabolism were determined and the nucleic acid content estimated cytophotometrically. A considerable decrease was found in cortisol metabolism by the lymphocytes from the 6th day after addition of an encephalitogenic mixture and there was a marked increase in the cortisol-resistant population of lymphocytes in guinea pigs with encephalomyelitis on the 17th–30th days after injection of the complete adjuvant. Cortisol in a concentration of 100 g% lowered the nucleic acid content of the lymphocytes of the intact animals but had no effect on lymphocytes of guinea pigs of the two experimental groups during the period of a considerable increase in the cortisol-resistant population. Progesterone depressed the lympholytic action of cortisol and the metabolism of this hormone by lymphocytes of intact guinea pigs. The ability of progesterone to reduce the lympholytic action of cortisol was weakened in guinea pigs with encephalomyelitis and guinea pigs receiving the adjuvant.Department of General Pathology, N. I. Pirogov Second Moscow Medical Institute. Allergologic Research Laboratory, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 200–202, February, 1977.  相似文献   
109.
Chemokines are a superfamily of small chemotactic proteins. While increased levels of interleukin-8 have been measured in serum and urine during urinary tract infection, little is known about other chemokines in this condition. Monocyte chemoattractant protein (MCP)–1, macrophage inflammatory protein (MIP)–1, MIP-1 and interferon- inducible protein (IP)–10 were measured in 30 patients with culture-proven urosepsis during a 3-day follow-up and in 11 healthy humans after intravenous injection of endotoxin (4 ng/kg). Urine and serum levels of MCP-1, MIP-1, and IP-10, but not of MIP-1, were elevated in patients on admission, and decreased after initiation of antibiotic treatment. Endotoxin administration to healthy subjects induced increases in plasma and urine concentrations of all four chemokines. These data indicate that clinical and experimental gram-negative infection in humans is associated with enhanced production of chemokines that act mainly on mononuclear cells and that these chemokines are at least in part locally produced.  相似文献   
110.
National Taiwan University College of Medicine (NTUCM) introduced small groups of teaching and basic-clinical integrated courses for medical students in 1992. By using computer network and multimedia techniques, this study tried to overcome barriers to learning in small group teaching. The Department of Medical Informatics of NTUCM established campus networking and computer classrooms and provided Internet and intranet network services including mail, netnews, bulletin board systems (BBS), world wide web (WWW), gopher, ftp and local file servers. To implement an interactive learning environment, the authors first tried mail lists, newsgroups and BBS. Next an integrated learning system prototype on the WWW was developed to provide functions including online syllabus, discussion boards simulated to BBS, online talk, interactive case studies, virtual classroom with video on demand (VOD) and Internet medical resources. The results showed that after the medical students completed the required course of medical informatics and had good network access using a network to communicate with each other became a daily practice. In the future, the system will extend to the tutoring of clinical practice and continuing medical education. The authors expect a national medical education network and more international cooperation and exchange.  相似文献   
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