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31.
32.
新生儿产伤79例分析 总被引:3,自引:1,他引:2
目的了解新生儿产伤种类及相关因素.方法用回顾性分析方法对该院23年间分娩造成的新生儿产伤共79例进行分析.结果23年间共分娩25 916例次,分娩造成的新生儿产伤共79例,发生率为3.05‰.产伤类型包括:骨折、臂丛神经损伤、产钳伤、刀伤、面瘫、口底损伤,其中以骨折为最多,计33例,占41.77%,骨折中颅骨骨折所占比例最大,25例(75.76%).与产伤关系最为密切的分娩方式是产钳助产.体重≥2500 g,发生新生儿产伤71例,占89.87%.新生儿产伤Apgar评分≤7分56例,占70.89%.结论正确选择分娩方式,把新生儿产伤降到最低点. 相似文献
33.
目的 研究海生多糖肽对小鼠亚急性辐射损伤的防护作用。方法 给小鼠饲以海生多糖肽制剂,用^60Coγ射线进行全身性亚急性照射,检测外周血白细胞、脾淋巴细胞转化率、红细胞超氧化物歧化酶、丙二醛和过氧化酶含量、精子畸形率、睾丸精母细胞染色体畸变率和肝细胞半胱氨酸蛋白酶-3等指标。结果 海生多糖肽高、低剂量组小鼠的血白细胞数量、脾淋巴细胞转化率、红细胞超氧化物歧化酶值和过氧化酶值均高于照射对照组,红细胞丙二醛值、精子畸形率、睾丸精母细胞染色体畸变率和肝细胞半胱氨酸蛋白酶-3阳性表达率则低于照射对照组,差异有显著性。结论 海生多糖肽对亚急性辐射损伤有良好的防护作用。 相似文献
34.
还原型谷胱甘肽和L-NAME对体外培养的脊髓运动神经元的影响 总被引:1,自引:0,他引:1
目的 :探讨还原型谷胱甘肽 (GSH)和L NAME对体外培养的脊髓运动神经元的保护作用。方法 :不同浓度的GSH和L NAME作用于脊髓运动神经元 ,3d后计算存活率。并测量存活率高的两组和对照组的免疫细胞化学标本的神经元形态学指标。结果 :GSH 10mmol·L-1和L NAME 1× 10 -3 mol·L-1组存活率最高。两实验组轴突长度、树突总长度、树突分叉点数目和胞体面积高于对照组。结论 :抗氧化剂和NOS抑制剂可以提高脊髓运动神经元的存活率 ,促进神经元生长 相似文献
35.
亮菌多糖抗小鼠辐射损伤作用的研究 总被引:2,自引:0,他引:2
目的观察亮菌多糖(ATS)对辐射损伤的保护作用。方法将小鼠随机分为空白对照组(0.9%生理盐水)、辐射模型组、阳性对照组(参芪片)和ATS多糖不同剂量实验组(80、160和320mg/kg)。以γ射线照射小鼠全身,引起辐射损伤后观察各组小鼠30d存活率、白细胞(WBC)数、精子畸变率、骨髓微核(MN)细胞数、骨髓DNA含量和免疫器官重量及血清和肝组织中的超氧化物歧化酶(SOD)和丙二醛(MDA)含量等。结果ATS能提高受照小鼠存活率(P〈0.05)及SOD活性(P〈0.05)、升高WBC数(P〈0.05)和骨髓DNA含量(P〈0.05),抑制小鼠精子畸变率(P〈0.05)和骨髓MN细胞数的增加(P〈0.05),并使受照小鼠胸腺、脾脏重量回升(P〈0.05),还能增加内源性脾结节数(P〈0.05),降低MDA含量。结论ATS对γ射线所致小鼠辐射损伤有较好的保护作用。 相似文献
36.
目的 :研究COPD肺心病急性加重期多个器官的受损情况。方法 :采用日本OLYMPUS公司AU10 0 0全自动生化分析仪测量 10 9例肺心病急性加重期患者的 17项血生化指标。并与 110例健康体检者进行对照研究。结果 :两组之间血肌酐 (Cr)差异不显著 (P >0 .0 5 ) ,总胆红素 (TBIL)及空腹血糖 (GLU)差异显著 (P <0 .0 5 ) ,其余 14项生化指标P值均 <0 .0 1,两组间差异非常显著。结论 :COPD肺心病急性加重期除了心力衰竭 ,呼吸衰竭之外 ,还常常伴有肝损害、肾损害、高血糖、低脂低胆固醇血症、低蛋白血症及营养不良。保肝护肾 ,注意血糖血脂及营养支持治疗不容忽视 相似文献
37.
We have reviewed some of the factors which contribute to lung damage by various toxicants. These include disposition of the chemical, its metabolism, individual cell type susceptibility and the potential for the tissue to repair. We have discussed the use of biochemical parameters to measure the functional activity of individual cell types in order to predict the damage to specific cell types and concluded that careful morphological analysis of lung tissue is likely to provide a more sensitive and informative measure of specific cell type injury. However, in order to investigate the mechanism of toxicity of pulmonary toxicants it is essential to establish the primary biochemical event that leads to cell damage and morphological change. The importance of separating the relevant biochemical change(s) from the cascade of biochemical events associated with dead and dying cells and the reparative response of the lung is emphasised.This report results from a discussion sponsored and organised by the Advisory Subgroup in Toxicology (AST) of the European Science Foundation's Standing Committee for the European Medical Research Councils and held at the Medical Research Council Toxicology Unit, Carshalton, U. K. Those taking part were: W. N. Aldridge (AST; as above); J. Bignon (Unit for Research in Renal and Pulmonary Pathology, University of Paris, Creteil, France); P. H. Burri (Section of Developmental Biology, Institute of Anatomy, University of Berne, Switzerland); G. M. Cohen (as above); D. Dinsdale (MRC Toxicology Unit, Carshalton U. K.); P. Hedqvist (Dept. of Physiology, Karolinska Institute, Stockholm, Sweden); D. Henschler (AST; Dept. of Toxicology and Pharmacology, University of Wurzburg, FDR); G. J. Laurent (Biochemistry Unit, Cardiothoracic Institute, University of London, London, U. K.); R. Lauwerys (AST Industrial and Medical Toxicology Unit, University of Louvain, Brussels, Belgium); F. Lembeck (AST; Dept. for Experimental and Clinical Pharmacology, University of Graz, Austria); N. Lery (AST; Poison Control Centre, Lyon, France); P. Moldeus (Dept. of Forensic Medicine, Karolinska Institute, Stockholm, Sweden); B. Nemery (MRC Toxicology Unit, Carshalton, U. K.); A. Saria (Dept. for Experimental and Clinical Pharmacology, University of Graz, Austria); L. L. Smith (as above);B. Terracini (AST; Dept. of Pathology and Cancer Epidemiology, University of Turin, Italy) 相似文献
38.
The firing rate of locus coeruleus (LC) neurons in rat brain slices was increased reversibly by agents that either elevate intracellular levels of adenosine 3',5'-cyclic monophosphate (cAMP) or mimic its actions (e.g., forskolin, and activator of adenylate cyclase, 8-Br-cAMP, a membrane permeable analog of cAMP, and Ro20-1724, a preferential inhibitor of cAMP-phosphodiesterase). Intracellular recordings showed that 8-Br-cAMP and forskolin induce a depolarization of LC neurons, accompanied by a decrease in input resistance. The 8-Br-cAMP- and forskolin-elicited depolarization persisted in the presence of cobalt, a calcium channel blocker. Steady-state current-voltage curves revealed that in the voltage range of -50 to -120 mV, 8-Br-cAMP and forskolin induced an inward current, which did not reverse at the potassium equilibrium potential and could not be blocked by tetrodotoxin. Partial replacement of sodium with Tris or choline markedly reduced the depolarization elicited by 8-Br-cAMP. We conclude that 8-Br-cAMP and forskolin act through a common mechanism to increase the firing rate of locus coeruleus neurons by inducing a cAMP-activated inward current, carried out at least in part by sodium ions. 相似文献
39.
Toxic effects of Fusarium mycotoxin butenolide on rat myocardium and primary culture of cardiac myocytes. 总被引:1,自引:0,他引:1
Jing-Bo Liu Yi-Mei Wang Shuang-Qing Peng Gang Han Yan-Sheng Dong Hai-Ying Yang Chang-Hui Yan Guo-Qiang Wang 《Toxicon》2007,50(3):357-364
Mycotoxin toxicosis has been implicated in the etiopathogenesis of Keshan disease (KD), an endemic cardiomyopathy prevailing in some regions of China. Butenolide (4-acetamido-4-hydroxy-2-butenoic acid gamma-lactone, CAS No. 16275-44-8), a mycotoxin produced by several Fusarium species such as Fusarium tricinctum and Fusarium graminearum, is frequently detected from the cereals in the endemic areas of KD. The present study is undertaken to investigate whether this mycotoxin can induce myocardial damage. Exposure of primary culture of cardiac myocytes to butenolide resulted in significant cytotoxicity, manifested by changes in cell morphology and decreases in cell viability. Consistent with the in vitro findings, distinct myocardial toxicity in vivo was observed after administration of rats by gavage with butenolide (10 and 20 mg/kg/day) for 2 months, and the myocardial injuries were characterized by focal necrosis of myocardium and fragmentation of myofiber. Butenolide also induced significant oxidative damage to the myocardium in vitro evidenced by a concentration-dependent lipid peroxidation in the myocardial homogenates, whereas antioxidants superoxide dismutase (SOD), N-acetylcysteine (NAC) and glutathione (GSH) provided significant protections against this oxidative effect. Taken together, these results clearly reveal that butenolide possesses the potential to induce myocardial toxicity. The present findings may reinforce the hypothesis that toxicosis by mycotoxins is one of the etiological factors for KD. 相似文献
40.
G Ferretti T Bacchetti R A Rabini A Vignini L Nanetti C Moroni L Mazzanti 《Diabetic medicine》2006,23(7):808-813
BACKGROUND: Homocysteine (Hcy) is an independent risk factor for cardiovascular disease (CVD). Individuals with Type 1 and Type 2 diabetes are more susceptible to the effects of homocysteine than non-diabetic subjects. The interaction between homocysteine-thiolactone (Hcy-thiolactone), a reactive product of Hcy, and low-density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL) and it has been suggested that homocysteinylation could increase atherogenicity of lipoproteins. AIM: The aim of the study was to compare the effect of in vitro homocysteinylation of LDL isolated from healthy control subjects (C-LDL) and from Type 1 diabetic patients (DM-LDL) and to investigate the effect of homocysteinylated LDL (Hcy-C-LDL and Hcy-DM-LDL) on peroxynitrite production of endothelial cells. METHODS: The in vitro homocysteinylation of LDL isolated from control (n = 12) and DM subjects (n = 12) was carried out by incubating lipoproteins with Hcy-thiolactone. The reaction was verified by quantifying the increase in sulphydryl groups (-SH groups) in Hcy-LDL with respect to control LDL. Control and homocysteinylated LDL were incubated with human aortic endothelial cells (HAEC) in culture. Peroxynitrite production in cells treated in different experimental conditions was assayed by a fluorimetric method. RESULTS: The increase in -SH groups after incubation with homocysteine was greater in LDL from diabetic subjects compared with LDL from control subjects (P < 0.001). In addition, peroxynitrite production from HAEC incubated with Hcy-LDL from diabetic patients was greater than after incubation with Hcy-LDL from control subjects and untreated LDL from diabetic patients (P < 0.001). CONCLUSIONS: These results show that LDL from diabetic patients is more susceptible to in vitro homocysteinylation than LDL from non-diabetic individuals and demonstrate that the compositional changes in Hcy-LDL from diabetic subjects have cytotoxic effects on human endothelial cells. 相似文献