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71.
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73.
原位杂交研究对虾白斑杆状病毒在虾体内感染过程   总被引:7,自引:0,他引:7  
应用地高辛标记的对虾白斑杆状病毒(white spot syndrome baculovirus,WSSV)核酸探针,与人工感染后不同时间采集的对虾组织样品进行原位杂交,以动态研究病毒从侵染至对虾以病死亡的过程。将典型感染WSSV的病虾组织投喂健康对虾,结果显示:WSSV道德通过侵染消化道上皮进入虾体内增殖,此后随着细胞裂解、病毒粒子释放,游离的粒子伴随血淋巴循环进而杂其它靶组织,直至对虾发病死亡  相似文献   
74.
在传染性非典型肺炎患者组织和血液中发现冠状病毒   总被引:4,自引:3,他引:4  
用RT-PCR从广东两例传染性非典型肺炎(非典型肺炎)死亡病例的肺和脾标本中,以及北京、辽宁和宁夏非典型肺炎患者血清中,扩增出冠状病毒核苷酸序列。这些PCR产物为冠状病毒RNA聚合酶基因部分片段,所有测定的序列和国内外SARS病毒序列相同。这些发现提示,冠状病毒和非典型肺炎关系密切,有助于确定我国非典型肺炎的病因。所建立的套式PCR方法可以用于检测临床标本。由于血液中存在SARS病毒,进行血清操作时需要注意安全保护。  相似文献   
75.

Background

HIV-1 matrix protein p17 variants (vp17s) detected in HIV-1-infected patients with non-Hodgkin's lymphoma (HIV-NHL) display, differently from the wild-type protein (refp17), B cell growth-promoting activity. Biophysical analysis revealed that vp17s are destabilized as compared to refp17, motivating us to explore structure-function relationships.

Methods

We used: biophysical techniques (circular dichroism (CD), nuclear magnetic resonance (NMR) and thermal/GuHCL denaturation) to study protein conformation and stability; Surface plasmon resonance (SPR) to study interactions; Western blot to investigate signaling pathways; and Colony Formation and Soft Agar assays to study B cell proliferation and clonogenicity.

Results

By forcing the formation of a disulfide bridge between Cys residues at positions 57 and 87 we obtained a destabilized p17 capable of promoting B cell proliferation. This finding prompted us to dissect refp17 to identify the functional epitope. A synthetic peptide (F1) spanning from amino acid (aa) 2 to 21 was found to activate Akt and promote B cell proliferation and clonogenicity. Three positively charged aa (Arg15, Lys18 and Arg20) proved critical for sustaining the proliferative activity of both F1 and HIV-NHL-derived vp17s. Lack of any interaction of F1 with the known refp17 receptors suggests an alternate one involved in cell proliferation.

Conclusions

The molecular reasons for the proliferative activity of vp17s, compared to refp17, relies on the exposure of a functional epitope capable of activating Akt.

General significance

Our findings pave the way for identifying the receptor(s) responsible for B cell proliferation and offer new opportunities to identify novel treatment strategies in combating HIV-related NHL.  相似文献   
76.
To study the role of Trichoderma in sick building syndrome, it is essential to be able to accurately identify species. Forty-four strains of Trichoderma spp. isolated from Danish buildings damaged by water leaks were identified using ITS1 ribotyping and universally primed PCR, UP-PCR. Ribotyping allowed the assignment of the strains into three distinct groups. High similarity of UP-PCR banding profiles of the strains allowed species designation for almost all strains (43 out of 44) when compared with the UP-PCR banding profiles obtained from reference strains of T. atroviride, T. citrinoviride, T. harzianum, T. longibrachiatum and T. viride. However, cross hybridization of UP-PCR products showed that the latter strain had high DNA homology to the ex-type strain of T. hamatum. The combined approach is a convenient way for reliable identification of Trichoderma strains.  相似文献   
77.
降低血粘度对慢性肺心病急性加重期疗效的影响   总被引:1,自引:0,他引:1  
张威  姜琳  祖静  周烁 《蛇志》2007,19(1):28-29
目的探讨血栓通降低血粘度对慢性肺心病急性加重期疗效的影响。方法将113例慢性肺心病急性加重期患者随机分为两组,观察组63例,对照组50例,两组病例均采取常规治疗(包括抗感染、改善通气、持续低流量吸氧、纠正心衰等),观察组同时应用血栓通注射液350mg加入生理盐水250ml中静滴,每日1次,15天为1疗程。两组病例治疗前、后分别检查血常规、血液流变学、血气分析和凝血常规4项。结果治疗前两组血液流变学数据无显著差异(P>0.05),治疗后观察组的血液流变学数据明显下降,组间差异非常显著(P<0.01)。组内比较观察组治疗后PaO2升高非常显著(P<0.01),PaCO2显著下降(P<0.05);对照组治疗后PaO2显著升高(P<0.05),PaCO2显著下降(P<0.05)。结论血栓通在降低血粘度,改善血液流变学的同时,使慢性肺心病急性加重期患者的低氧血症和高碳酸血症也得到显著纠正。  相似文献   
78.
The mangroves Rhizophora lamarkii, Ceriops roxburghiana, Bruguiera gymnorrhiza, Aegiceras corniculatum, and Lumnitzera racemosa were screened for their carbon metabolic pathways by measuring net photosynthetic rate (P N), 13C discrimination rate, leaf anatomy, titratable acidity, and activities of phosphoenolpyruvate carboxylase, NADH-malate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, and pyruvate phosphate dikinase. The tested mangroves had a well developed succulence, opening of stomata during day time and closure in the night hours, and absence of diurnal fluctuation of organic acids in their leaves which excludes the possibility of these species being CAM plants. Moreover, the leaf anatomy had not exhibited Kranz syndrome. The high values of discrimination against 13C, low P N, high CO2 compensation concentration, and the activities of aminotransferases in the direction of alanine formation suggest that the species may follow C3 mode of carbon metabolic pathway.  相似文献   
79.
To understand molecular responses of crustacean hemocytes to virus infection, we applied 2-DE proteomics approach to investigate altered proteins in hemocytes of Penaeus vannamei during Taura syndrome virus (TSV) infection. At 24 h postinfection, quantitative intensity analysis and nano-LC-ESI-MS/MS revealed 11 forms of 8 proteins that were significantly up-regulated, whereas 9 forms of 5 proteins were significantly down-regulated in the infected shrimps. These altered proteins play important roles in host defense (hemocyanin, catalase, carboxylesterase, transglutaminase, and glutathione transferase), signal transduction (14-3-3 zeta), carbohydrate metabolism (acetylglucosamine pyrophosphorylase), cellular structure and integrity (beta-tubulin, beta-actin, tropomyosin, and myosin), and ER-stress response (protein disulfide isomerase). Semiquantitative RT-PCR and Western blot analysis confirmed the upregulation of 14-3-3 at both mRNA and protein levels. Interestingly, several altered protein spots were identified as fragments of hemocyanin. Mass spectrometric analysis showed that the hemocyanin spots at acidic and basic regions represented the C- and N-terminal hemocyanin fragments, respectively. As three-quarters of C-terminal fragments were up-regulated, whereas two-thirds of N-terminal hemocyanin fragments were down-regulated, we therefore hypothesize that C- and N-terminal hemocyanin fragments may have differential roles in hemocytes. Further investigation of these data may lead to better understanding of the molecular responses of crustacean hemocytes to TSV infection.  相似文献   
80.
为提高对肺炎克雷伯菌感染所致肝脓肿侵袭综合征的临床表现及其危害的认识,回顾性分析3例确诊为肺炎克雷伯菌感染所致肝脓肿患者的临床经过、治疗反应及转归。结果发现3例患者均有肝外播散性病灶,符合肝脓肿侵袭综合征的临床特征。这3例患者为社区获得性感染,均有肝脓肿,其中2例合并眼内炎并造成失明,1例合并腰椎感染、腹主动脉感染及感染性心内膜炎。2例有糖尿病病史,1例免疫正常。结合文献复习,发现肺炎克雷伯菌感染引起肝脓肿及肝外播散性病灶,临床上称为肝脓肿侵袭综合征,大多由高毒力肺炎克雷伯菌引起,好发于糖尿病及免疫缺陷人群,也可发生于免疫正常人群,治疗困难,临床危害严重,需引起重视。  相似文献   
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