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981.
自1990年以来收治直径在2-5.6cm的大、巨型垂体腺瘤33例。依肿瘤生长形态与扩展范围将其简略分为三种类型。A型:瘤体位于鞍内或侵入蝶窦;B型;瘤体呈椭圆形或哑铃向鞍上扩展,三脑室明显移位抬高;C型:瘤体巨大侵入三脑室阻塞室间孔或明显的鞍周扩展。 相似文献
982.
流行性出血热人群传播速度的定量研究 总被引:1,自引:0,他引:1
选取家鼠型EHF中发病区人群血清EHF抗体阳性率资料,试用可逆催化模型对EHF人群传播速度进行定量研究。结果表明:所建立的可逆催化模型其理论值与实际值理论拟合较好,用χ^2做配合适度检验,P〉0.05。证实可逆催化模型可用来作EHF人群中传播速度的定量研究。还发现在家鼠型EHF疫区每1000人中约有80人因有效接触而获得感染,同时又有40人血清EHF抗体转阴。 相似文献
983.
1. The effect of strophanthidin on the slow inward current (Isi) and on contractile force were studied in guinea-pig isolated ventricular myocytes and intact papillary muscles, respectively. In myocytes, both low (10 nmol/L) and high (1-10 mumols/L) concentrations had small or no effects in either direction on Isi whereas norepinephrine (10-100 nmol/L) increased it. To determine whether the same results are obtained after decreasing or increasing intracellular calcium or sodium, the same concentrations of strophanthidin were tested in different procedures that are known to (i) increase [Ca]i and decrease [Na]i (high [Ca]o, 3.6-5.4 mmol/L; low [Na]o, 112 mmol/L; (ii) decrease [Ca]i and increase [Na]i (low [Ca]o, 0.45-1 mmol/L; Sr, 1 mmol/L; (iii) decrease [Ca]i and [Na]i (Cd, 0.1-0.2 mmol/L); and (iv) increase [Ca]i and [Na]i (veratridine, 0.2 mumol/L). High [Ca]o and veratridine increased whereas low [Ca]o and Cd decreased Isi. In contrast, during these various procedures, strophanthidin had small and inconsistent effects at a low or high concentration. In intact papillary muscles, low strophanthidin decreased whereas high strophanthidin increased contractile force. It is concluded that strophanthidin has little direct or indirect effect on Isi and that the decrease in force by low and increase in force by high concentrations in intact muscle are probably related to demonstrated decrease and increase, respectively, in intracellular sodium activity. 相似文献
984.
985.
986.
Mohamad H Yamani Randall C Starling James B Young Daniel Cook Yang Yu D Geoffrey Vince Patrick McCarthy Norman B Ratliff 《The Journal of heart and lung transplantation》2002,21(9):983-989
BACKGROUND: A cascade of inflammatory reactions characterize acute vascular rejection after heart transplantation. This study was undertaken to test the hypothesis that acute vascular rejection is associated with up-regulation of vitronectin receptor (alphavbeta3), increased expression of tissue factor, and activation of the extracellular matrix metalloproteinase induction system. METHODS: Acute vascular rejection developed in 14 heart transplant recipients within 2 weeks of transplantation, confirmed by immunofluorescence (AVR group). We compared these patients with 10 transplant recipients who had no evidence of acute vascular rejection or peritransplant ischemic injury (control group). We evaluated endomyocardial biopsy specimens for alphavbeta3, tissue factor, and extracellular matrix metalloproteinase inducer (EMMPRIN). RESULTS: Compared with the control group, the AVR group demonstrated evidence of significantly increased expression of alphavbeta3 (1.9-fold, p < 0.001), tissue factor (1.8-fold, p < 0.001), and EMMPRIN (1.5-fold, p < 0.001). All patients in the AVR group received plasmapheresis; 11 of 14 patients had evidence of ischemic necrosis on biopsy specimens, and 3 of 14 patients experienced hemodynamic compromise and graft dysfunction and died within 3 weeks of transplant. Another patient died at 10 months after transplant. CONCLUSIONS: Acute vascular rejection is associated with up-regulation of alphavbeta3, tissue factor, and activation of the matrix metalloproteinase induction system, which may contribute to the lethal morbidity associated with this disease. 相似文献
987.
The motor neuron disease (MND) refers to a group of progressive diseases with unknown reasons, which attacks the cells of the anterior horn of the spinal cord, the motor nuclei of the brain stem cranial nerves and the pyramidal cells of the cerebral motor cortex. It is characterized in clinic by atrophy of the muscles, myasthenia and even death due to paralysis of the respiratory muscle. Currently, there is still no any effective cure for this illness. 50-70% of the victims will die in 3 to 5 years, and the survival time for those with brain stem injuries is no more than two years.1 Since 1996, the authors have treated 31 cases of motor neuron disease with large dosage of qi-invigorating drugs in accordance with Prof. Liu Mocai's experience, and obtained certain therapeutic effects. A report follows. 相似文献
988.
原代培养神经细胞膜经N—甲基—D—D天冬氨酸和MK—801作用后原子力微镜观察 总被引:4,自引:0,他引:4
目的:对比观察正常培养皮层神经元在N-甲基-D-天冬氨酸(NMDA)及其受体拮抗剂-MK-801作用下膜表面三维构像形态的改变。方法:利用分辨率为0.1-0.01nm的原子力显微镜(AFM)对原代培养大鼠皮层神经细胞膜表面进行纳米尺度的扫描观测。结果:正常神经元膜表面光滑,起伏均匀,隆起的颗粒状蛋白密集,间隔规律。NMDA损伤后神经元破碎,崩解,膜失去连续性,NMDA+MK-801作用下神经元膜皱折增加,边缘粗糙,起伏程度介于前两者之间,结论:(1)AFM具有分辨率高,制样简单特点,(2)AFM能细微地分辨损伤保护作用后引起的细胞膜表面三维形态改变。(3)NMDA作用后膜结构开始解体,膜蛋白颗粒聚集增大,脂质凹陷加深,间距增宽,表面粗糙度增加。 相似文献
989.
高脂血症患者C—反应蛋白含量的变化及氟伐他汀对它的影响 总被引:4,自引:1,他引:3
Dong-Sheng Chi Feng-Xia Jin Shu-Guang Yang Yu-Wen Su Bin Ge Jie Zhang Yan Zhang Yi-Li Liu 《第一军医大学学报》2002,22(12):1109-1111
OBJECTIVE: To observe the changes of C-reactive protein (CRP) level and its relationship with blood lipids, and the effects of fluvastatin on CRP and the lipids in patients with hyperlipidemia. METHODS: Serum levels of cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C) and lipoprotein(a)[Lp(a)] were measured by enzyme assay, and plasma CRP level by immunonephelometry before and after fluvastatin treatment (20 mg/d for 4 weeks) in patients with hyperlipidemia. RESULTS: CRP levels were above normal in 90.3% hyperlipidemia cases in spite of the various accompanying diseases. Fluvastatin treatment significantly reduced TC (-7.49%), TG (-14.32%), LDL (-13.88%), VLDL (-18.48%) and TC/HDL(-13.50%) levels (P<0.01), and also brought down Lp(a) concentration (-13.81%). CRP levels was very effectively reduced after the treatment (-15.92%, P<0.001). No association between basal CRP levels and basal lipids and Lp(a) concentrations was observed. Positive correlation of CRP, however, was observed after fluvastatin treatment with TC/HDL (r=0.62, P=0.041) and Lp(a) (r=0.320, P=0.011), while inverse relations were noted between CRP and HDL (r=-0.288, P=0.023). CONCLUSION: CRP levels increases markedly in patients with hyperlipidemia, a fact that is independent of the accompanying diseases. In addition to modulating blood lipid levels, fluvastatin also reduces CRP level, the latter possibly serving as an independent predictive factor for atherosclerotic cardiovascular diseases and also as an indicator for estimating the effectiveness of the treatment. 相似文献
990.