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81.
M.H. THERKILDSEN N. CHRISTENSEN L.J. ANDERSEN S. LARSEN M. KATHOLM 《Histopathology》1992,21(2):167-171
Malignant transformation of a benign Warthin's tumour (adenolymphoma) is extremely rare. The light microscopic and ultrastructural features of an adenocarcinoma arising in a Warthin's tumour in the parotid gland are described. Light microscopy demonstrated a transition zone from the benign to the malignant component, and the malignant cells revealed oncocytic features by both light- and electronmicroscopy. 相似文献
82.
为探讨免疫性血小板减少性紫癜(ITP)中医辨证分型与免疫机理的关系,将ITP患者中医辨证分型结合血小板相关抗体(PAIg)及T淋巴细胞亚群进行分析。发现作为本病主要抗体的PAIgG脾肾阴亏型明显高于脾虚失统型(P<0.01);OKT8+值亦显著高于脾虚失统型(P<0.05),OKT4+/OKT8+比值则明显低于脾虚失统型(P<0.05)。提示脾肾阴亏型的免疫损伤程度较脾虚失统型严重。 相似文献
83.
目的 观察时空隧道酒保健作用。方法 采用碳末廓清、溶血素测定方法观察时空隧道酒对免疫功能的影响 ;利用果蝇寿命、小鼠血清SOD和MDA的含量测定法观察时空隧道酒的抗衰老作用 ;用雄性小鼠交配能力和去势小鼠精液囊、前列腺和包皮腺重量测定法观察时空隧道酒对性功能影响 ;用小鼠负重游泳法观察时空隧道酒的抗疲劳作用。结果 时空隧道酒能增强小鼠单核巨噬细胞吞噬功能 ,提高小鼠血清溶血素含量 ;延长果蝇平均寿命和最高寿命 ,提高老年小鼠血清SOD的活力和降低MDA的含量 ;提高雄性小鼠交配能力 ,增加去势小鼠精液囊 前列腺和包皮腺重量 ;并能延长小鼠游泳时间。结论 时空隧道酒具有增强机体免疫功能、抗衰老、提高性功能和抗疲劳作用 相似文献
84.
The present study was undertaken to elucidate the effect on platelet aggregation of the prothrombin-converting reaction on platelets with or without activated protein C (APC). A reaction mixture of washed platelets from human individuals, Factor Xa and prothrombin markedly induced platelet aggregation; maximum aggregation rates, 31.3–92.5%, and times to reach to maximum aggregation, 11.6 to 20.1 min. This aggregation was inhibited by the addition of APC with 50% inhibition concentration (IC50) value of 14.4 U/ml. APC also inhibited thrombin generation in the reaction mixture in a dose-dependent manner with IC50 value of 0.96 U/ml. However, APC did not inhibit the thrombin (0.1 CU/ml)-induced platelet aggregation at concentrations of up to 30 U/ml. These findings suggest that APC has no direct inhibitory effect on platelet aggregation and that APC inhibits platelet aggregation through inhibition of thrombin generation. 相似文献
85.
Kaoru Hatanaka Xiang-An Li Ling Guo Toshiyuki Sakata Judith A. Gillissen Akira Yoshioka Akira Yamamoto 《Thrombosis research》1994,74(6):643-654
We have experienced a coagulation factor VIII-deficient patient whose plasma has normal protein S (PS) activity and masses of free PS and its bound form in complex with C4b-binding protein (C4BP). Although the patient's plasma showed a normal ratio of free PS to PS-C4BP complex in the presence of 5 mM EDTA, the plasma gave an abnormally retarding major C4BP peak together with a major PS peak in the crossed immunoelectrophoresis (CIE) in the presence of 2 mM CaCl2. It was revealed that the major peak was formed by a mixture of PS-C4BP complex and free form. The addition of normal human plasma (NHP) to the patient's plasma inhibited the retardation of the major PS-C4BP complex. These suggest that the patient's plasma lacks some component(s) to inhibit Ca2+-dependent association of PS with C4BP. 相似文献
86.
Relationship between plantar pressure distribution under the foot and insole comfort 总被引:2,自引:0,他引:2
《Clinical biomechanics (Bristol, Avon)》1994,9(6):335-341
In this paper, four pairs of insoles with different comfort characteristics were used to investigate the relationship between the pressure distribution under the foot and running shoe comfort. Fourteen male subjects were tested in four insole conditions by walking and running on a treadmill. The pressure at the plantar surface of the foot was measured by using an EMED pressure-measuring insole. For walking there were significantly higher pressures and forces in the midfoot area and significantly lower pressures in the medial forefoot and hallux area by wearing the most comfortable insole compared with wearing the least comfortable insole. The shift of the pressure from forefoot to midfoot for the most comfortable insole provided an even distribution of the pressure at the plantar surface of the foot. The results also demonstrated that the path of centre of force at the plantar surface of the foot moved to the lateral aspect of the foot for the most comfortable insole. For running, only the pressure in the medial forefoot area was found significantly lower for the most comfortable insole than for the least comfortable insole. The results of this study indicated that the pressure distribution between the plantar surface of the foot and the shoe could detect the change of shoe comfort. Thus it is a suggestion that pressure measurement may be related to understand factors important for shoe comfort.
Comfort of sport shoes is important for the appropriate execution of sport activities. Additionally, comfort may influence fatigue and possibly the development of injuries. The quantification of comfort of sport shoes and the understanding of mechanical and/or biological functions related to it may be enhanced with the use of pressure measurements between the plantar surface of the foot and the shoe sole. 相似文献
87.
目的:探讨妊娠小于34周早产分娩方式的选择。方法:妊娠小于34周早产患者126例分为剖宫产组67例和阴道分娩组59例,比较不同分娩方式对分娩结局的影响。结果:孕28—30+6周时,阴道分娩组的新生儿死亡率明显高于剖宫产组(P〈0.05),其他两个孕周期间的两组新生儿死亡率比较无显著差异。阴道分娩组和剖宫产组的新生儿的死亡数随着出生体重的逐渐增加而不断减少,新生儿体重小于1500g时,两种分娩方式的死亡率之间比较存在显著性差异。结论:早产的主要原因是妊娠并发症,降低新生儿不良结局的根本措施还应延长孕龄,提高新生儿生存能力。 相似文献
88.
目的优选萎胃宁浓缩丸制剂的最佳提取工艺。方法以芍药苷提取量、正丁醇浸出物、乙酸乙酯浸出物为指标,采用均匀设计法筛选最佳提取工艺。结果乙醇浓度60%,提取次数2次,溶剂用量16倍,每次提取时间65min为最佳提取工艺。结论所得提取工艺稳定性好,可用于萎胃宁浓缩丸的制备。 相似文献
89.
目的探讨Fas配体阳性睾丸细胞对共移植的胰岛细胞存活起全身和/或局部的免疫豁免作用。方法将同种大鼠胰岛细胞与不同数量的睾丸细胞同侧或两侧共移植于糖尿病受体肾包膜下,观察移植物功能和存活情况,以及移植物内淋巴细胞凋亡。结果单纯移植胰岛组(对照组)平均存活期为(4.6±1.1)天。睾丸细胞和胰岛细胞同侧共移植时,当睾丸细胞数为1×106(A组)时,胰岛细胞平均存活期为(23.8±4.6)天;睾丸细胞数增至1×107时(B组),胰岛细胞存活期大于(57.5±4.0)天,均较对照组明显延长(P<0.01)。两侧共移植时,当睾丸细胞数为1×105(C组),胰岛细胞平均存活期为(6.0±1.4)天,与对照组相似(P>0.05);睾丸细胞数增至1×106(D组),胰岛细胞存活期(11.5±3.1)天较对照组或C组延长(P<0.01);睾丸细胞数增至1×107(E组)时,胰岛细胞存活期(31.2±15.9)天延长更加明显(P<0.01)。相同剂量的睾丸细胞与胰岛细胞分别同侧和两侧共移植时发生移植排斥反应各自的病理表现是不同的,前者移植物内有淋巴细胞浸润,部分胰岛玻璃样变,抗胰岛素抗体染色仅见少量阳性细胞,而后者胰岛细胞移植物内有大量的淋巴细胞和少量的中性粒细胞浸润,抗胰岛素抗体阳性细胞较少,未见胰岛玻璃样变。原位细胞凋亡检测发现同侧共移植后的移植物与肾实质交界处有淋巴细胞凋亡。电镜检查发现胰岛移植物存活超过60d的标本可见大量存活的胰岛细胞团和睾丸Sertoli细胞,有散在的凋亡淋巴细胞。结论睾丸细胞与同种胰岛细胞移植后不仅可诱导局部免疫豁免,而且也具有一定的全身免疫保护作用,但较局部免疫豁免作用弱;这些作用可延长移植物的存活期,并具有剂量依赖性。 相似文献
90.