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991.
腕关节关节囊内韧带的解剖观察及其创伤学意义   总被引:4,自引:2,他引:4  
本文描绘了腕关节关节囊内韧带的解剖,其中首次描述了中腕关节的韧带连结,即大、小多角骨,头状骨至舟状骨的韧带和钩骨至三角骨的韧带.本文还论述了与这些韧带连结方式密切相关的腕骨生理运动特点及维持腕关节稳定性的因素.文章还讨论了与腕关节关节囊内韧带有关的腕部创伤学特点.  相似文献   
992.
本文作者用诊断剂量的超声波辐照活体家兔肝脏,喂养3d致死后取材,经处理后用电子显微镜观察其超微结构的变化情况。实验结果表明超声波辐照20min的家兔肝脏的超檄结构无明显变化,而辐照30min及60min的家兔肝脏,除细胞质内粗面内质网有程度不同的扩张外,肝组织及肝细胞的其它结构均无明显改变。由于热效应与辐照时间有关,而本实验辐照30min及60min的家兔肝脏的超微结构的变化是相同的。且本实验所用超声强度小而不致引起机械效应。因此作者认为本实验出现的兔肝细胞粗面内质网扩张的现象不会是热效应和机械效应引起,而只可能是空化效应所致,这说明诊断超声可能在动物组织中引起空化效应。  相似文献   
993.
应用微血管灌注透明法观察研究5具成人周围神经干标本.重点观察神经自然分束部位微血管形态和分支分布规律.神经干内有非常完兽的血供系统.手术中循神经自然分束进行追踪分离,不会对神经血供产生明显影响.但在张力下牵拉缝合神经,将对神经干血供产生严重影响.神经束膜缝合比神经外膜缝合更强调在无张力下进行.  相似文献   
994.
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   
995.
The purpose of this study was to investigate the therapeutic potential of interferon-beta (IFN-beta) against tumors that resist its antiproliferative effects. Mouse fibrosarcoma cells (UV-2237m-P) and their counterparts, transfected with either IFN-beta cDNA (UV-2237m-IFN-beta) or its control vector (UV-2237m-neo), were used in the study. UV-2237m-IFN-beta cells, still expressing functional IFN receptors, were resistant to the antiproliferative effects of IFN-beta. UV-2237m-P and UV-2237m-neo cells produced progressive tumors in both nude and IFN receptor-null nude (IFNAR-/-nude) mice. In contrast, growth of UV-2237m-IFN-beta cells was significantly delayed in nude mice. UV-2237m-IFN-beta tumors from nude mice contained fewer microvessels, fewer proliferating cells, and more apoptotic cells than did UV-2237m-P and UV-2237m-neo tumors. They expressed high levels of inducible nitric oxide synthase (iNOS) and were densely infiltrated by macrophages. Incubation with macrophages from nude mice, but not those from IFNAR-/- nude mice or iNOS-null/nude mice, led to more significant killing of UV-2237m-IFN-beta cells than that of control cells, which was blocked by iNOS inhibitor N-methylarginine. Similarly, more UV-2237m-IFN-beta cells were killed when they were incubated with spleen lymphocytes from nude mice. These data indicate that IFN-beta can inhibit growth of IFN-beta-resistant tumors by T cell-independent host-mediated mechanisms, including the role of macrophages, natural killer (NK) cells, and iNOS activity.  相似文献   
996.
目的探讨阿尔茨海默氏病(AD)和帕金森氏病(PD)对老年人认知功能及日常生活能力的影响。方法对2000~2003年就诊于我院的53例AD、68例PD和60例正常人应用简易智力量表(MMSE)和日常生活能力量表(ADL)进行分析。结果AD组与对照组相比MMSE总分及各因子分、ADL总分及各单项分均有显著性差异(P<0.01):PD组与对照组相比除MMSE的记忆力和语言因子分以及ADL第13项目(打电话)外,其余均有显著性差异(P<0.05):AD组与PD组相比除ADL第7项(穿衣)外均有显著性差异(P<0.05)。结论AD和PD对老年人的认知功能和日常生活能力均有显著的影响,两者相比,AD对老年人的影响更严重、更广泛。  相似文献   
997.
Wong T  Zhang XL  Asl MN  Wu CP  Carlen PL  Zhang L 《Neuroscience》2005,134(1):107-120
The local circuitry of the mammalian limbic cortices, including the hippocampus, is capable of generating spontaneous rhythmic activities of 0.5-4 Hz when isolated in vitro. These rhythmic activities are mediated by synchronous inhibitory postsynaptic potentials in pyramidal neurons as the result of repeated discharges of inhibitory interneurons. As such, they are thought to represent an intrinsic inhibitory rhythm. It is unknown at present whether such a rhythm occurs in the immature rodent hippocampus and, if so, the postnatal time window in which it develops. We explored these issues using our recently developed whole mouse hippocampal isolate preparation in vitro. We found that spontaneous rhythmic field potentials started to emerge in mouse hippocampal isolates around postnatal day 10, stabilized after postnatal day 15 and persisted into adulthood. In postnatal days 11-14 mouse hippocampi, the properties of these rhythmic potentials were in keeping with a CA3-driven, IPSP-based intrinsic network activity. The lack of spontaneous field rhythm in neonatal (postnatal days 2-7) hippocampi cannot be attributed to the excitatory activities mediated by gamma-aminobutyric acid type A (GABA-A) receptors, as chloride-dependent hyperpolarizing inhibitory postsynaptic potentials were detectable in neonatal pyramidal neurons at voltages near resting potentials and pharmacological antagonisms of GABA-A receptors produced robust epileptiform discharges in neonatal hippocampi. High frequency afferent stimulation or applications of 4-aminopyridine at low micromolar concentrations failed to induce persistent field rhythm in neonatal hippocampi, suggesting that an overall weak glutamatergic drive is not the sole causing factor. We suggest that the inhibitory postsynaptic potential-based spontaneous rhythmic field potentials develop in a discrete time window during the second postnatal week in the mouse hippocampus due to a fine-tuning in the structure and function of CA3 recurrent circuitry and associated GABAergic inhibitory interneurons.  相似文献   
998.
The copper and Iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than In LEA rats (P<0.05). But for the free iron level there was no signiflcant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher In LEC rats than In LEA rats (P<0.01). The 4–hydroxy-2–nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect In the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneo-plastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important translation metals In the body, may participate In the Induction of DNA damage and oncogenesls  相似文献   
999.
张万洲 《解剖学杂志》1992,15(3):171-173
本文应用EPM-810Q电子探针,对53例35~60岁健康成年人白发与黑发(指长在同一部位、相邻单根白发与黑发),进行微量元素分析,结果表明:白发中Mg、Al、Cd、Ca、Cr、Mn、Fe、Se微量元素含量明显小于黑发,而Cu、Zn、Pb元素含量大于黑发。以上差异有显著性意义(P<0.001),并对上述差异进行了讨论。  相似文献   
1000.
Monoclonal antibodies reactive with B and T lymphocytes, monocytes, and granulocytes were applied to B-5-, Bouin's-, or formalin-fixed paraffin-embedded sections. Most antigens were destroyed or masked by fixation or embedding procedures, or both. However, T200, an antigen present in all lymphoid and hematopoietic cells, and Leu M1, an antigen in granulocytes, were well preserved in formalin-fixed tissues. Leu 1 and BA-1, antigens present on T and B lymphocytes, respectively, were preserved in Bouin's-fixed specimens. With careful selection of fixatives, identification of some T and B lymphocytes and granulocytes by monoclonal antibodies in paraffin-embedded specimens is possible.  相似文献   
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