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1.
In this paper, the characteristics and regularities of acute ocular injuries by direct laser exposure are briefly reviewed, typical cases of ocular injuries from accidental laser exposure are reported, and laser occupational harm to the eye are discussed on the basis of epidemic investigation of personnel engaged in laser work.  相似文献   
2.
目的:研究热盐水灌胃导致的大鼠萎缩性胃炎胃粘膜组织中的凋亡细胞及其调控基因Bcl-2,Fas表达状态,以探讨长期热咸饮食与慢性萎缩性胃炎发生的关系。方法:采用脱氧核糖核酸转移酶介导等缺口末端标记(TUNEL)技术及免疫组织化学染色技术。细胞凋亡对DNA含量分析采用流式细胞检测技术。结果:TUNEL检测细胞凋亡显示,在热盐水所致的大鼠萎缩性胃炎中凋亡细胞数明显增多,在粘膜全层均可见到,呈弥漫性分布。萎缩性胃炎中凋亡细胞指数显著高于正常大鼠胃粘膜;免疫组化法检测凋亡相关基因显示,Bcl-2,Fas在热盐水灌胃所致的萎缩性胃炎中的表达率显著高于正常胃粘膜;热盐水灌胃不同时间大鼠胃粘膜中Bcl-2,Fas蛋白表达率随灌胃时间延长而逐渐增加,在4周、8周、12周时Bcl-2蛋白表达率分别为12.5%、16.7%、76.5%,Fas蛋白表达率分别为18.75%,22.2%,64.7%;流式细胞检测显示,在萎缩性胃炎时,在G0/G1峰前可见一个亚G0/G1峰,也即凋亡细胞峰出现,而在正常胃粘膜时未显示亚G0/G1峰。结论:热盐水灌胃可导致大鼠胃粘组织细胞凋亡异常,其凋控基因(Bcl-2,Fas)在热盐水所致的大鼠萎缩性胃炎发生中起重要作用。  相似文献   
3.
BACKGROUND: The cerebral ischemia and ischemia/reperfusion animal models are used to simulate the human cerebrovascular diseases is one of the popular topics of neurological science recently. To study the pathophysiology, pathogenesis, prophylaxis and treatment of ischemic cerebrovascular diseases and to establish the ideal animal model that is the most similar to the human cerebral ischemia, are the topics that the people generally cared about. OBJECTIVE: To evaluate the effects of aerocyst-blocking bilateral ascending pharyngeal artery on the establishment of cerebral ischemia models by using digital subtraction angiography (DSA), magnetic resonance diffusion-weighted imaging (DWI) and magnetic resonance perfusion-weighted imaging (PWI). DESIGN: Repetitive measure animal experiment. SETTING: Zhongshan Hospital Affiliated to Dalian University. MATERIALS: The experiment was carried out in the Animal Laboratory (Provincial Laboratory), Zhongshan Hospital of Dalian Univeristy from January to May 2006. A total of 14 domestic piglets, of 6 months old, weighing 12–15 kg, of either gender, were selected from Animal Experimental Center, Dalian University. Multistar T.O.P digital subtraction angiography machine was provided by Siemens Company, German. METHODS: Aerocyst-blocking bilateral ascending pharyngeal artery was used to establish cerebral ischemia models. And then, Multistar T.O.P. DSA was used for imaging of cerebral vessels before blocking, during blocking and at 0.5 and 2 hours after ischemia perfusion. GE Signa 1.5 T supraconduction magnetic resonance imaging was used for DWI examination; in addition, PWI was used based on focal sites and areas. Otherwise, magnetic resonance imaging (MRI) was used to detect signal changes of T1WI and T2WI in ischemic areas. MAIN OUTCOME MEASURES: Analytic results of DSA, DWI, PWI and MRI. RESULTS: All 14 experimental piglets were involved in the final analysis. ① DSA: The blood flow of bilateral ascending pharyngeal arteries and its branch were blocked at blocking phase, which restored 0.5 and 2 hours after reperfusion. ② DWI and PWI: There were no observable abnormalities in PWI and DWI at pre-blocking. Abnormal increased signals were found on both DWI and PWI at during and post-blocking. There were reduction in ADC and rCBF and delay in rTTP at all time points except pre-blocking. ③ MRI: There were no abnormal signals observable at any time of pre- and post-blocking in T1WI and T2WI. CONCLUSION: It is feasible to establish this kind of animal experimental models, and it can simulate the ischemic state; meanwhile, the existence and extent can be showed directly by DSA, DWI, and PWI.  相似文献   
4.
AIM: To determine the safety, tolerability and pharmacokinetic parameters of a new drug recombinant human parathyroid hormone [ rhPTH (1-84)] in healthy male Chinese subjects. METHODS: domly divided Thirty-six healthy male volunteers were rangroups received into 3 groups. The volunteers in these single subcutaneous injection of rhPTH ( 1-84) in a dosage of 1, 2 and 4 μg/kg respectively. Blood samples were obtained before and after administration within 24 hours. The rhPTH concentrations in sennn were determined by enzyme linked immunosorbent assay (ELISA). The pharmacokinetic parameters determined with use of standard noncompartmental analysis were the maximum serum concentration ( Cmax ), the time to attain that concentration ( tmax ), and the area under the serum concentration-time curve up to 24 hours( AUC0-24 ) and up to infinity (AUC0-∞). Dose proportionality of pharmacokinetic parameters (AUC, Cmax of every volunteer of each dosage and A UC was computed from log transformed data) and was examined by mean of analysis of variance (ANOVA) using SPSS software package. In the study, subjects' symptoms, objective signs, and vital signs, including blood pressure, heart rate, respiratory rate and body temperature, were checked and 12-lead electrocardiography was recorded before and after drug administration within 24 hours. Routine laboratory tests, including hematology, blood biochemistry, serum electrolyte, and urinalysis, were performed before and after drug administration within at 24 hours.[第一段]  相似文献   
5.
By digital subtraction angiography(DSA), the authors made observations on 108 normal ophthalmic arteries in 80 patients with regard to the origins, courses, branching, morphology and anastomoses of the vessels. The merits and demerits of DSA in observing the ophthalmic artery were discussed. Eye Science 1994; 10: 157- 162.  相似文献   
6.
7.
目的 研究心血管危险因子载脂蛋白 E( Apo E)、载脂蛋白 C- ( Apo C- )以及低密度脂蛋白受体相关蛋白 ( LRP)与汉族迟发性阿尔茨海默病 ( LOAD)之间的相关性。方法 应用 PCR-RFLP技术或直接通过 PCR方法 ,分析了 1 5 6例正常老年人、79例 LOAD Apo E、Apo C- 与 LRP基因型。结果 在 LOAD患者组和正常对照组中 ,Apo Eε4等位基因出现的频率分别为 1 7.7%、5 .7% ,其间差异有显著性 ( x2 =1 5 .75 0 ;P=0 .0 0 1 ,OR=3 .3 96,95 % CI =1 .80 8~ 6.3 79) ;Apo Eε3等位基因频率分别为 76.0 %、84% ,前者低于后者 ( x2 =4.43 9;P=0 .0 3 5 ,OR=1 .65 9,95 % CI =1 .0 3 3~ 2 .665 ) ;LRP、Apo C- 基因的基因型频率和等位基因频率在 LOAD与对照组之间差异无显著性 ( P >0 .0 5 )。结论  Apo Eε4等位基因是 LOAD的遗传危险因子 ,Apo Eε3等位基因则可能有保护效应 ;此研究未能证明 Apo C- 基因变异和 LRP基因 C766T多态性与 LOAD有相关关系  相似文献   
8.
9.
Extended -spectrum β -lactamases(ESBLs)aremainlyproducedbymembersofthefamilyEnter obacteriaceaewhichcanhydrolyzeβ -lactamantibi oticsincludingthethird - generationcephalosporinandaztreonam ,theESBLs- producingbacillishowedmedian -highresistancetoceftazidimeandaztreonamparticularly[1] .NowadaystheprevalenceofESBLs -producingstrainshavebeenreportedinmanyareasaroundtheworld[2 ] .ButthereisfewinformationabouttherelationshipbetweentheuseofantibioticandtheproductionofESBLs .Weperformedastud…  相似文献   
10.
THECLONINGOFNa ̄+/Ca ̄(2+)EXCHANGERGENEANDITSEXPRESSIONINBRAINISCHEMIATangJian汤健,WangYu王瑜,ZkangChenhui张晨晖,E.CostaInstituteofCar...  相似文献   
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