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101.
本文用HRP示踪技术发现丘脑腹后核小细胞部向岛皮质有明确的定位投射,此发现为探索内脏性传入通路提供新的形态学资料.本文还用Nissl法研究了丘脑腹后核小细胞部的细胞构筑,为丘脑腹后核小细胞部的核团划分、形态特征及细胞构筑学积累了资料. 相似文献
102.
Cellular characterization of blastocysts derived from rabbit 4-, 8- and 16-cell embryos and isolated blastomeres cultured in vitro 总被引:2,自引:0,他引:2
The purpose of this study was to investigate the developmental potential of isolated rabbit blastomeres under various culture conditions to gain insight into their ability to form the two cell lineages of a viable blastocyst. Intact embryos at the 4-cell, 8-cell, 16-cell stages and blastomeres isolated from 4-, 8- and 16-cell rabbit embryos (1/4, 1/8 or 1/16 blastomeres respectively) were cultured in drops of one of three different media, each supplemented with either fetal calf serum (FCS), bovine serum albumin (BSA) or polyvinyl alcohol (PVA). The effects of the extracellular matrix fibronectin (FN) on the development of isolated rabbit blastomeres were also investigated. Supplementation of the medium with FCS yielded a higher (P < 0.05) proportion of blastocysts than BSA or PVA, predominantly from 1/4 blastomeres. No major differences were found between the three basic culture media. In 1/4, 1/8 or 1/16 blastomeres, blastocyst formation rates were greater (P < 0.05) in groups cultured in matrix-free (54.5, 59.6 and 54.6% respectively) than in FN-coated groups (35.4, 46.0 and 26.1% respectively). Only in blastocysts derived from 1/4 blastomeres, were the numbers of inner cell mass (ICM) and total cells of blastocysts higher (P < 0.05) in FN-coated groups than in matrix-free groups (12.7 +/- 1.1 versus 8.5 +/- 0.7 ICM, 73.8 +/- 3. 7 versus 57.8 +/- 3.3 total cells). The percentage of blastocysts derived from single blastomeres with ICM cells decreased with increasing cell stage of the parent embryos in FN-coated (93.6, 78.3 and 44.0%, respectively) as well as matrix-free groups (96.2, 69.3 and 55.2%). In FN-coated groups, after 96 h (1/4) or 72 h (1/8 and 1/16) of culture, approximately 20-30% of blastomeres did not develop into normal blastocysts but formed sheets with 30-50 cells attached to the bottom of the dishes. These results indicate that the development of rabbit blastomeres shares important characteristics with those from mouse and domestic species and may thus aid in developing an efficient culture system for blastomeres, derived from human embryos. 相似文献
103.
目的 探讨经舟骨月骨周围脱位的诊断和治疗。方法 回顾性分析17例经舟骨月骨周围脱位病例,背侧型13例,掌侧型4例;新鲜损伤组10例中8例行撬拨复位成功,仅2例因舟骨对位不良接受手术治疗;陈旧性组7例中均接受手术,4例行开放复位内固定,3例行近排腕骨切除术。结果 采用Cooney评价标准,优11例,良3例,可1例,差2例,优良率82.35%。结论 经舟骨月骨周围脱位的早期治疗简单且疗效较好,而一旦误诊,则多数需手术治疗,且残留不同程度的功能障碍。提高对本病损伤机制、腕部体征和影像学特点的认识和了解,减少误诊。是提高本病预后的关键因素之一。 相似文献
104.
目的:为临床经下颌下咽后入路处理颅颈交界腹侧区病变提供解剖学基础。方法:对15例(30侧)带颈头颅标本模拟经下颌下咽后入路进行显微外科解剖,同时进行了有关的数据测量。结果:该入路浅层的重要结构均位于各自的筋膜层中,以这些结构为解剖学标志可鉴别各层并引导手术进行。咽结节是显露的上限,限制骨窗侧方显露范围的各重要结构的内缘距正中线的水平距离分别为寰枢外侧关节,左(7.78±1.03)mm,右(7.81±1.01)mm;寰枕关节,左(9.27±1.86)mm,右(9.22±1.69)mm;舌下神经管内口,左(12.76±2.77)mm,右(12.81±2.53)mm及椎动脉C2水平,左(18.36±2.27)mm,右(18.47±2.14)mm;C1水平左(25.35±2.31)mm,右(25.18±2.33)mm;穿硬膜处,左(12.69±2.42)mm,右(12.72±2.39)mm。结论:(1)经下颌下咽后入路解剖上大致可分为3个层次:浅层,深层和骨、韧带及硬膜层。(2)掌握每个层次的解剖特点及操作要点,有助于安全充分的显露和处理咽颅颈交界腹侧区病变。 相似文献
105.
目的 探讨双丁酰 环核苷酸 (db cAMP)对转化细胞增殖及细胞表型作用的机理。 方法 以流式细胞光度术 (flowcytometry ,FCM)、软琼脂集落形成、放射免疫、Northern印迹和激酶活性分析等方法观察db cAMP对转化的C3H1 0 T1 2 小鼠成纤维细胞增殖、细胞表型、钙调素 (calmodulin ,CaM)表达及蛋白激酶Ⅱ (proteinkinaseⅡ ,PKⅡ )活性的影响。 结果 db cAMP(1mmol L)使C3H1 0 T1 2 转化细胞增殖及软琼脂集落形成能力受到显著抑制 ,转化细胞中CaM的表达及PKⅡ活性明显高于正常细胞 ,经db cAMP处理后也受到明显抑制。 结论 细胞转化及cAMP的诱导分化作用与PKⅡ活性的改变有密切相关性 相似文献
106.
107.
本文介绍了盲人智能探路手杖的研究.该系统由单片机控制,采用两只超声波传感器的探测模式,对盲人行进路上的路况进行探测和分析,并针对不同的路况发出相应的提示信息,以达到辅助盲人安全行走的目的. 相似文献
108.
Genetic diversity of the outer surface protein C gene of southern Borrelia isolates and its possible epidemiological,clinical, and pathogenetic implications 下载免费PDF全文
The ospC genes of 20 southern Borrelia strains were sequenced. The strains consisted of B. burgdorferi sensu stricto, B. andersonii, B. bissettii, one undescribed genospecies, MI-8, and one probably new Borrelia species, TXW-1. A high degree of similarity exists between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Lateral transfers of the ospC gene probably occurred between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Internal gene recombination appears to occur among them. The highest degree of genetic diversity among them was observed in the two variable domains (V1 and V2), semivariable domain (SV), and the species-specific epitopes (between amino acids 28 and 31). Differences in ospC sequences among southern strains reflect diversity at the strain and genospecies levels. MI-8, which was recognized as an undescribed genospecies in our previous reports, remains distinguishable in our current analysis of ospC genes and is distinct from B. burgdorferi sensu stricto. Interestingly, another undescribed southern isolate, TXW-1, was not amplified under various PCR conditions. Compared to European B. burgdorferi sensu stricto strains, American B. burgdorferi sensu stricto strains show greater genetic heterogeneity. Southern B. burgdorferi sensu stricto, B. andersonii, and B. bissettii isolates were intermixed with each other in the phylogenetic trees. In the derived trees in our work, at least one southeastern strain of B. burgdorferi, MI-2, most closely aligns with a so-called invasive cluster that possesses many proven human-invasive strains. Transmission experiments show that MI-2 and the strains in this group of southern spirochetes are able to infect mice and hamsters and that the typical vector of Lyme disease, Ixodes scapularis, can acquire the spirochetes from infected mammals. Currently, strain MI-2 appears to be the only southern isolate among the 20 we analyzed that clusters with an OspC invasive group and thus might be invasive for humans. 相似文献
109.
Lehner T Bergmeier LA Wang Y Tao L Sing M Spallek R van der Zee R 《European journal of immunology》2000,30(2):594-603
Heat shock proteins (HSP) are widely distributed and highly immunogenic molecules. A novel property reported here is that stimulation with HSP70 of CD8-enriched T cells derived from naive non-human primates caused a dose-dependent increase in concentrations of the beta-chemokines RANTES, macrophage inflammatory protein (MIP)-1alpha or MIP-1beta. However, the concentrations of these beta-chemokines were greatly increased when the CD8 T cells derived from HSP70-immunized non-human primates were stimulated with HSP70. HSP linked to peptides or proteins combined generation of beta-chemokines with an adjuvant function by enhancing specific T cell proliferative responses and IgG and IgA antibodies. The beta-chemokine and adjuvant functions were also elicited by topical mucosal administration of HSP linked to an antigen. We postulate that microbial HSP can stimulate beta-chemokine production which may be responsible for innate adjuvanticity, as was found in cells eluted from normal rectal mucosal tissue, and constitutes a significant component of the mucosal-associated lymphoid system. Furthermore, stimulation of innate immunity may drive adaptive immunity and account for the protective effects of HSP against tumors and viruses. 相似文献
110.
人缺血脑组织中IP-10和IFN-γ的表达 总被引:1,自引:0,他引:1
目的:探讨趋化因子IP-10和细胞因子IFN-γ是否参与人缺血脑损伤过程。方法:将21例脑梗死死亡病例按发病持续时间分为〈7天、7~14天和15~21天3组,以非缺血侧半球做对照,用HE染色法观察炎性细胞浸润情况;通过免疫组织化学方法检测缺血半球脑组织与非缺血半球脑组织中趋化因子IP-10和细胞因子IFN-γ的表达。结果:在〈7天组和7~14天组中,缺血脑组织可见大量炎性细胞浸润。在〈7天组、7~14天组和15~2l天组中,趋化因子IP-10在缺血半球脑组织中的表达高于非缺血半球(分别是1.74倍增高,P〈0.01;1.41倍增高,P〈0.05和1.52倍增高,P〈0.01)。在对细胞因子IFN-γ的检测中发现〈7天和7~14天组中,IFN-γ在缺血半球脑组织中的表达高于非缺血半球(分别是1.65倍增高,P〈0.05和1.32倍增高,P〈0.05);在15~21天组中,IFN-γ在缺血半球与非缺血半球中的表达没有显著差异(P〉0.05)。结论:在人缺血脑组织中观察到IP-10和IFN-γ的表达,提示IP-10和IFN-γ参与了炎症反应对脑组织的损伤过程。同时也提示IP-10可能参与后期对损伤脑组织的修复。 相似文献