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141.
本文通过免疫荧光(IF)和电镜(EM)技术对新疆出血热(XHF)及流行性出血热(EHF)病毒的生物学特性在Vero E_6及LLC-MK_2两株传代细胞上进行了比较。两种病毒感染两株细胞后免疫荧光染色有两种不同的荧光形态特征,两种病毒对细胞的敏感性明显不同,XHF病毒在LLC-MK_2细胞上感染后6~8天可出现明显的细胞病变,而EHF病毒感染此细胞后则不引起病变。电镜观察到两种病毒在LLC-MK_2细胞中都能形成与布尼病毒相似的形态特征。  相似文献   
142.
韦壮苗 《护理研究》2007,21(5):457-458
创建安全、舒适的住院环境,是现代医院竞争的手段之一。医院服务的主要对象是病人,所以医院与病人之间需要在最大限度内、以最短的时间达到相互适应,即病人在心理、生活环境和医疗配合上与医院相适应[1]。按规定,医院绿化用地要占总用地的60%~65%[2],大型综合医院绿化用地要占总占地面积≥35%[3],以达到防尘、防风、隔离、净化空气及夏季调节温度和湿度的要求。而绿化的草地和一些树木,也是蚊子生长和繁殖的场所。蚊子在病人的面前飞翔并叮咬病人,就会引起病人在视觉上和感觉上的不适应,使病人想起不被蚊子叮咬的家居环境或办公环境,并与之…  相似文献   
143.
A randomly selected sample of 662 12-year-old Hong Kong children, 529 of whom were Southern Chinese and 133 non-Chinese, was clinically examined for dental caries. The DMFT values were 2.76 and 1.66 for the Chinese and non-Chinese children, respectively. The D component for the Chinese children was 2.12, while for the non-Chinese children it was only 0.45. Approximately 24.0% of the Chinese children had attended the dentist because they were in pain. Only 3.8% of the Chinese children had sought orthodontic or preventive treatment, compared with 24.0% of the non-Chinese children. Although these findings indicate the caries experience to be well below the FDI/WHO global goal for the year 2000, there is a great need to increase the level of dental awareness among Chinese children.  相似文献   
144.
Infusions made from 15 Chinese, 11 Ceylon/Indian and 6 herb teas (1 g/100 ml deionized water at 85 degrees C) were analyzed for F, P, Ca, Al, Mg, Mn and Zn. Chinese teas continued to release F throughout the first hour of infusion, whereas release of F from Ceylon/Indian teas was essentially completed after 5 minutes. After a 15-minute infusion, the mean F concentration in Chinese teas was 1.73 ppm, and in Ceylon/Indian teas it was 1.24 ppm. Herb teas contained a negligible amount of F (0.02-0.05 ppm). Phosphorus and Mg were the most abundant of the other elements with an average of 12.5 and 9.1 ppm, respectively. A high correlation (r = 0.81) was found between the released F and Al. The total F content in tea leaves ranged from 82 to 371 ppm. The addition of milk to tea infusions did not appreciably reduce the F concentration. The estimated daily F intake from tea infusion made with fluoridated water at 0.7 ppm is 1.05 mg.  相似文献   
145.
本文以大鼠为实验对象,观察了γ线8Gy照后胃组织内乙酰胆碱含量、胆碱酯酶活性及平滑肌对乙酰胆碱反应性的变化。结果表明,照后1/24~l天胃组织内乙酰胆碱含量明显下降,3天趋向正常,5天基本恢复至照前水平。胃组织的胆碱酯酶活性在照后l/24~5天基本无改变。在同一剂量照后1h,胃窦平滑肌对乙酰胆碱的反应与照前近似,l天后开始减弱,3天后明显下降,与正常相比有非常显著差异。  相似文献   
146.
曹维  赵德化 《医学争鸣》1989,10(6):405-408
采用细胞内微电极记录技术,同步观察了3,6-[二甲氨基]-二苯并碘因甲酸盐(IHC-64)对豚鼠心乳头肌细胞动作电位和收缩力的作用。50μmol/L IHC-64抑制心肌收缩力,而不影响快反应动作电位。增加IHC-64浓度,动作电位0相最大峰值(APA)、除极速率(dp/dt_(max))和复极50%和90%时程(APD_(50)、APD_(90))被明显抑制。IHC-64抑制慢反应动作电位,提高细胞外钙浓度可拮抗这种抑制。结果提示,IHC-64主要抑制慢Ca~(2+)内流,同时也部分抑制快Na~+内流,它可能是一种新型B类钙通道阻滞剂。  相似文献   
147.
随着医院信息化程度的提高,建立有效的医院信息网络系统安全体系成了重要的课题.在充分认识到病毒危害的前提下,本文阐述了医院信息系统内软件和硬件的防病毒策略.  相似文献   
148.
重型颅脑损伤后凝血功能变化的研究   总被引:2,自引:1,他引:1  
徐玮  沈宏 《浙江创伤外科》2007,12(2):98-101
目的研究重型颅脑损伤后凝血功能的变化及临床意义。方法对本院2005年3月至2006年2月收治的26例重型单纯性颅脑损伤患者(GCS≤8分)进行前瞻性研究,监测其入院当时、入院第2天、第3天及第7天的部分凝血活酶时间(APTT),凝血酶原时间(PT),纤维蛋白原(FIB)及凝血时间(TT)的变化。并检测14例单纯头部外伤患者在入院时的APTT、PT、FIB和TT值。结果APTT在入院3天明显升高。1周后仍未达到正常(P〈0.05);PT在入院当天即升高(P〈0.05),1周左右逐步恢复正常;FIB在入院当天即升高,第3天下降(P〈0.05),1周左右逐步恢复正常。有3例按照DIC诊断标准诊断为DIC,结果在观察期间均死亡。结论重型颅脑损伤后可发生凝血功能异常,且外凝性凝血途径的启动早于内源性凝血途径。伤后早期即可发生高凝状态,至第3天左右向低凝状态转变,1周左右恢复正常。  相似文献   
149.
Lymphomatoid granulomatosis (LG) is a potentially malignant lymphoproliferative disorder. The lung is the most common involved site, followed by the skin and nervous system. However, LG of the central nervous system presenting with Parkinsonism is very rare. We report a patient with LG who presented with parkinsonian features such as bilateral rigidity, bradykinesia, and agitation. Brain magnetic resonance imaging showed multifocal punctuate enhanced lesions in both supra- and infratentorial areas. Steroid pulse therapy resulted in a dramatical improvement in the symptoms and MRI abnormalities.  相似文献   
150.
Paget's disease is a focal condition of bone. To study changes in cells within pagetic lesions, we cultured osteoblasts and stromal cells from 22 patients and compared gene expression in these cells to cells from healthy bone. We identified several differentially regulated genes, and we suggest that these changes could lead to the formation of the lesions. INTRODUCTION: Paget's disease is a focal condition of bone of unknown cause. Although it is regarded as primarily an osteoclast disorder, the tight coupling of the activity of osteoclasts and osteoblasts suggests that the osteoblast could play a key role in its pathogenesis. The aim of the study was to identify possible changes in pagetic osteoblasts and stromal cells that might contribute to the development of pagetic lesions. MATERIALS AND METHODS: Candidate genes were identified based on known bone cell regulators, supplemented with microarray analysis. Gene expression was determined by real-time PCR in primary cultures of osteoblasts and bone marrow stromal cells from pagetic patients and control subjects. Concentrations of secreted proteins were determined by ELISA. RESULTS: Dickkopf1 mRNA and protein levels were increased in both pagetic osteoblast and stromal cell cultures, and interleukin (IL)-1 and IL-6 were overexpressed in pagetic osteoblasts. These changes parallel recent findings in myeloma bone disease, which shares some clinical similarities with Paget's disease. Alkaline phosphatase was overexpressed, and bone sialoprotein and osteocalcin were underexpressed in pagetic osteoblasts, consistent with their circulating levels in pagetic patients. It is hypothesized that overexpression of Dickkopf1, IL-1, and IL-6 would result in stimulation of osteoclast proliferation and inhibition of osteoblast growth, leading to the development of the characteristic lytic bone lesions. By stimulating osteoblast differentiation, Dickkopf1 and IL-6 may also promote mineralization, leading to the conversion of lytic lesions to sclerotic. CONCLUSIONS: These findings suggest that dysregulated gene expression in pagetic osteoblasts could cause the changes in bone cell number and function characteristic of Paget's disease.  相似文献   
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