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71.

Background  

Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India  相似文献   
72.
报道了采自内蒙古呼伦贝尔市的中国疣柄牛肝菌属1个新记录种,即假褐疣柄牛肝菌Leccinum pseudoscabrum(Kallenb.)utara.。主要特征为菌肉伤后变红到紫褐色,再到黑褐色,基部菌丝体手触后呈紫褐色;具泡状菌丝,呈栅栏状。比较和讨论了该种与相近种在伤后不同的变色反应及菌丝形态。研究标本存放于吉林农业大学菌物标本馆(HMJAU)。  相似文献   
73.
鞘氨醇-1-磷酸(sphingosine-1 phosphate, S1P)是一种脂质信号分子,与细胞增殖、凋亡和迁移等有密切关系.本研究发现,S1P促进人脐带间充质干细胞(human umbilical cord mesenchymal stem cells, hUC-MSCs)增殖,但目前关于其作用信号通路及S1P对hUC-MSCs表面标记表达的影响尚不十分清楚.Real-time PCR检测hUC-MSCs中S1P受体mRNA表达情况,发现在hUC-MSCs中优势表达S1PR1 3,而S1PR4、S1PR5的表达很少.MTT法检测S1PR1/3拮抗剂VPC23019、S1PR2拮抗剂JTE013、S1PR3拮抗剂CAY10444、Gi蛋白抑制剂PTX和ERK抑制剂PD98059对S1P诱导hUC-MSCs增殖的影响.结果显示,VPC23019完全抑制S1P诱导的hUC MSCs增殖,JTE013对此没有明显影响,CAY10444部分抑制S1P诱导的hUC MSCs增殖,PTX、PD98059完全抑制S1P诱导hUC-MSCs增殖.进一步用Western印迹检测ERK1/2磷酸化水平揭示,S1P通过促进ERK1/2磷酸化进而促进hUC MSCs增殖.流式细胞术检测发现,S1P对hUC MSCs表面标记物(CD45、CD34、CD90、CD29、CD105、CD44、CD73、CD71)表达没有明显影响.本研究证明,S1P通过S1PR1/3、Gi偶联蛋白及ERK1/2信号通路促进hUC MSCs增殖,而对hUC MSCs表面标记物表达无明显影响.  相似文献   
74.
Cryopreservation of immature bovine oocytes by vitrification in straws   总被引:3,自引:0,他引:3  
The aim of this study was to cryopreserve by vitrification by ethylene glycol (EG) and dimethyl sulfoxide (DMSO) immature bovine oocytes in straws and to investigate the effects of vitrification on post-thaw oocyte maturation. A total of 575 cumulus oocyte complexes were obtained by follicle aspiration from 238 ovaries of cows slaughtered at a local abattoir. Following selection, oocytes with compacted cumulus cells and evenly granulated ooplasm were vitrified using one of the three different solutions with a non-vitrified group served as control. The first step vitrification solution contained 20% EG while the second step solution contained 40% EG+1M sucrose in a basic media used in group EG. Oocytes were matured in N-2-hidroxyethyl piperazine-N-2-ethanosulfonic acid (HEPES) buffered tissue culture medium (TCM) 199 for 24h at 39 degrees C in a humidified atmosphere of 5% CO2 in air. Oocytes were fixed following evaluation for polar body formation, stained with Giemsa solution and nuclear maturation was examined. The numbers of oocytes which were observed at Metaphase II (MII) stage were 41 (34.1%), 17 (14.9%), 29 (20.7%) and 78 (79.6%) in groups EG, DMSO, Mix and Control, respectively. Maturation rate distribution in group Mix was not statistically different when compared to maturation rate distributions in groups EG and DMSO (p>0.05). Differences between other groups were significant (p<0.001). However, better results were obtained in EG group compared to DMSO and mix groups. Maturation rates were lower in all treatment groups than the control group. The lowest maturation result was obtained in DMSO group. Maturation rate in group Mix was between maturation rates of EG and DMSO groups. Immature bovine oocytes can be vitrified in straws, but maturation success differs with the cryoprotectant and it seems that to obtain better maturation rates, new cryopreservation techniques specific for immature bovine oocytes are needed.  相似文献   
75.
流式细胞术研究细胞凋亡的方法与技术   总被引:1,自引:0,他引:1  
细胞发生凋亡时,会伴随着一系列形态学、生物化学及分子生物学性质的变化,包括细胞皱缩,核染色质凝聚,细胞膜通透性改变,Caspases激活,线粒体跨膜电位降低,膜磷酯酰丝氨酸外化,胞质Ca2+浓度升高,DNA片段化及含量变化等特点.应用流式细胞术进行细胞凋亡的研究,对于探讨胚胎发育、衰老以及研究肿瘤的发生、发展和转化等病理生理过程和病毒感染及免疫等具有十分重要的意义.本文就细胞凋亡的特征、基于细胞膜功能的流式细胞术检测方法和基于细胞器功能的流式细胞术检测方法等关键性问题进行了阐述.  相似文献   
76.
圆瓣姜花根茎挥发油的化学成分   总被引:1,自引:0,他引:1  
利用水蒸汽蒸馏法提取圆瓣姜花根茎挥发油,运用毛细管气相色谱-质谱联用法对挥发油进行了分析,分离出60个峰,鉴定了其中的51种成分,所鉴定成分占挥发油总量的97.32%,其主要化学成分为单萜及倍半萜类化合物。  相似文献   
77.
大鼠子宫内膜异位模型的建立与组织学观察   总被引:8,自引:1,他引:7  
目的为开发诊治子宫内膜异位症(endometriosis,EMT)的新药研究提供理想的动物模型。方法取雌性未交配性成熟大鼠,术前雌激素诱导,麻醉开腹取部份右侧子宫,将内膜种植于左腹壁内,术后16周取出包块,进行组织形态学、组织化学观察。结果异位内膜在腹壁内生长,呈隆起囊状小包块,内有黏液,具有正常子宫内膜基本组织结构,囊腔较大。异位内膜中有糖原、RNA的存在。结论该手术方法建立的子宫异位内膜生长良好,术后一周就可摸及包块大小,为开发研究子宫内膜异位症的新药提供了方便。  相似文献   
78.
We have demonstrated that interactions within the conserved serpin breach region play a direct role in the critical step of the serpin reaction in which the acyl-enzyme intermediate must first be exposed to hydrolyzing water and aqueous deacylation. Substitution of the breach tryptophan in PAI-1 (Trp175), a residue found in virtually all known serpins, with phenylalanine altered the kinetics of the reaction mechanism and impeded the ability of PAI-1 to spontaneously become latent without compromising the inherent rate of cleaved loop insertion or partitioning between the final inhibited serpin-proteinase complex and hydrolyzed serpin. Kinetic dissection of the PAI-1 inhibitory mechanism using multiple target proteinases made possible the identification of a single rate-limiting intermediate step coupled to the molecular interactions within the breach region. This step involves the initial insertion of the proximal reactive center loop hinge residue(s) into beta-sheet A and facilitates translocation of the distal P'-side of the cleaved reactive center loop from the substrate cleft of the proteinase. Substitution of the tryptophan residue raised the kinetic barrier restricting the initial loop insertion event, significantly retarding the rate-limiting step in tPA reactions in which strong exosite interactions must be overcome for the reaction to proceed.  相似文献   
79.
Experiencing the New Genetics: Family and Kinship on the Medical Frontier. Kaja Finkler. Philadelphia: University of Pennsylvania Press, 2000. 296 pp.
Born and Bred: Idioms and New Reproductive Technologies in England. Jeanette Edwards. New York: Oxford University Press, 2000. 264 pp.  相似文献   
80.
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