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991.
血栓性血小板减少性紫癜37例临床分析   总被引:1,自引:0,他引:1  
目的:总结分析血栓性血小板减少性紫癜(TTP)患者临床表现,实验室特点及治疗反应,以提高TTP诊断水平和治疗效果。方法:对我院1998年1月~2009年4月期间诊断为TTP的37例患者进行临床特征和治疗转归分析,对所有病例的外周血涂片进行破碎红细胞计数,计数5000个红细胞中所含裂红细胞进行定量。结果:37例患者仅7例(18.9%)出现典型TTP五联征(发热、血小板减少、微血管病性溶血性贫血、神经系统症状和肾脏损害);30例TTP患者(81.1%)出现三联征(血小板减少、微血管病性溶血性贫血、神经系统症状)。本组病例中主要的致病因素为自身免疫性疾患,特发性TTP占56.76%。本组病例外周血涂片100%存在破碎红细胞,均值为4.4%,范围为0.3%~13.4%。本组病例的治疗以血浆置换和输注血浆为主,治疗有效率88.46%;接受血浆输注治疗的患者缓解率仅为18%,而死亡率为82%。结论:TTP诊断仍然依赖临床表现特点,破碎红细胞计数是非常有价值的诊断指标。血浆置换联用血浆输注仍是治疗TTP的首先方法。  相似文献   
992.
Thousand-kernel weight (TKW) is one of the major components of grain yield in wheat (Triticum aestivum). Identifying major quantitative trait loci (QTLs) for TKW and developing effective markers are prerequisite for success in marker-assisted selection (MAS) to improve wheat yield through breeding. This study mapped a major QTL, designated as TaTKW-7AL, for increasing TKW on the long arm of chromosome 7A of ‘Clark’ to a 1.3-cM interval between single nucleotide polymorphism (SNP) markers IWB13913 and IWA5913. This QTL explained 19.7 % of the phenotypic variation for TKW. A QTL for increasing kernel length (KL), one of the major components of TKW, was mapped in the same interval as TaTKW-7AL, suggesting that increased TKW by the QTL in ‘Clark’ is most likely due to the increased KL. Association analysis on a diversity panel of 200 US winter wheat accessions also identified a haplotype of three SNP markers (IWB13913, IWB6693 and IWA5913) that were tightly associated with the both KL and TKW. The analysis of allele frequencies of the haplotype in the diversity panel suggested that the favorable allele of TaTKW-7AL has not been strongly selected for in practice and has potential to be used to improve grain yield in US hard winter wheat breeding. Two user-friendly flanking KASPar markers, IWB13913 and IWA5913, were developed for MAS of TaTKW-7AL.  相似文献   
993.

Background

Human leukocyte antigen (HLA) genes are critical genes involved in important biomedical aspects, including organ transplantation, autoimmune diseases and infectious diseases. The gene family contains the most polymorphic genes in humans and the difference between two alleles is only a single base pair substitution in many cases. The next generation sequencing (NGS) technologies could be used for high throughput HLA typing but in silico methods are still needed to correctly assign the alleles of a sample. Computer scientists have developed such methods for various NGS platforms, such as Illumina, Roche 454 and Ion Torrent, based on the characteristics of the reads they generate. However, the method for PacBio reads was less addressed, probably owing to its high error rates. The PacBio system has the longest read length among available NGS platforms, and therefore is the only platform capable of having exon 2 and exon 3 of HLA genes on the same read to unequivocally solve the ambiguity problem caused by the “phasing” issue.

Results

We proposed a new method BayesTyping1 to assign HLA alleles for PacBio circular consensus sequencing reads using Bayes’ theorem. The method was applied to simulated data of the three loci HLA-A, HLA-B and HLA-DRB1. The experimental results showed its capability to tolerate the disturbance of sequencing errors and external noise reads.

Conclusions

The BayesTyping1 method could overcome the problems of HLA typing using PacBio reads, which mostly arise from sequencing errors of PacBio reads and the divergence of HLA genes, to some extent.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2105-15-296) contains supplementary material, which is available to authorized users.  相似文献   
994.
一种新的肉苁蓉甙类化合物的分离方法   总被引:2,自引:2,他引:2  
简单介绍了一种从肉苁蓉中提取得到肉苁蓉甙类化合物的方法,避免了乙酸乙酯和正丁醇的萃取,便于工业化应用,同时还可获得纯度较高有甜菜碱。  相似文献   
995.
NGF initiates the majority of its neurotrophic effects by promoting the activation of the tyrosine kinase receptor TrkA. Here we describe a novel interaction between TrkA and GIPC, a PDZ domain protein. GIPC binds to the juxtamembrane region of TrkA through its PDZ domain. The PDZ domain of GIPC also interacts with GAIP, an RGS (regulators of G protein signaling) protein. GIPC and GAIP are components of a G protein-coupled signaling complex thought to be involved in vesicular trafficking. In transfected HEK 293T cells GIPC, GAIP, and TrkA form a coprecipitable protein complex. Both TrkA and GAIP bind to the PDZ domain of GIPC, but their binding sites within the PDZ domain are different. The association of endogenous GIPC with the TrkA receptor was confirmed by coimmunoprecipitation in PC12 (615) cells stably expressing TrkA. By immunofluorescence GIPC colocalizes with phosphorylated TrkA receptors in retrograde transport vesicles located in the neurites and cell bodies of differentiated PC12 (615) cells. These results suggest that GIPC, like other PDZ domain proteins, serves to cluster transmembrane receptors with signaling molecules. When GIPC is overexpressed in PC12 (615) cells, NGF-induced phosphorylation of mitogen-activated protein (MAP) kinase (Erk1/2) decreases; however, there is no effect on phosphorylation of Akt, phospholipase C-gamma1, or Shc. The association of TrkA receptors with GIPC and GAIP plus the inhibition of MAP kinase by GIPC suggests that GIPC may provide a link between TrkA and G protein signaling pathways.  相似文献   
996.
Hepatocellular carcinoma (HCC) is a severe liver malignancy with few drug treatment options. In finding an effective treatment for HCC, screening drugs that are already FDA-approved will fast track the clinical trial and drug approval process. Connectivity Map (CMap), a large repository of chemical-induced gene expression profiles, provides the opportunity to analyze drug properties on the basis of gene expression. Support Vector Machines (SVM) were utilized to classify the effectiveness of drugs against HCC using gene expression profiles in CMap. The results of this classification will help us (1) identify genes that are chemically sensitive, and (2) predict the effectiveness of remaining chemicals in CMap in the treatment of HCC and provide a prioritized list of possible HCC drugs for biological verification.  相似文献   
997.
For a novel potential commercial chiral pesticide, an independent study on the fate characteristics and residues of each stereoisomer is essential if the application rates for the pesticide and human exposure are to be reduced. The absorption and translocation behavior of a chiral insecticide, cycloxaprid, in plants treated by root immersion and blade smearing was studied using 14C‐labeling tracer techniques. With the root treatment, total absorption of (1R;8S)‐cycloxaprid (RS) (12.39%) was much greater than that of (1S;8R)‐cycloxaprid (SR) (3.31%) at 192 h after treatment (HAT). The mass concentrations ( RS / SR ) of cycloxaprid in the roots, cotyledons, leaf 1, leaf 2, and leaf 3 were 37.0/16.8, 8.3/2.8, 11.7/6.5, 5.1/4.8, and 8.0/4.7 mg kg‐1 (fresh weight), respectively, at 192 HAT at an initial concentration 1.6 mg kg‐1. With the foliar application treatment, no significant difference was observed between the total absorption of RS (3.11%) and SR (4.03%) at the end of the treatment. Both acropetal and basipetal transport of absorbed 14C occurred and more than 71.83% of absorbed RS and 82.42% of SR remained in the treated leaf. Stereoselective absorption was observed during root uptake but not during foliar absorption. Chirality 25:686–691, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
998.
Trichoderma reesei is an important cellulase producer and its secondary mycelial phase is responsible for cellulase expression and secretion in submerged fermentation. Little is known regarding the effects of fungal morphology on cellulase production by Trichoderma sp. In this study we aimed to extend the understanding of cellulase production by T. reesei, especially correlating cellulase productivity with pellet morphology and with its secretome characteristics. We found that T. reesei was more likely to form pellets in malt extract broth than in potato dextrose broth. CaCO(3) helped in formation of fine pellets in malt extract broth. 10(9) spores/ml resulted in formation of pellets with the size of 0.13 ± 0.047 mm. LC/MS spectrometry analysis indicated that the secretomes from pellet was different from that of mycelial mat under the same fermentation conditions. Optimization tests showed that lactose, xylose and Pluronic F68 are important for efficient production of cellulases with FPU activity in the pellets fermentation. This is the first report on the artificial formation of pellets by Trichoderma sp. as well as correlation between physiological characteristic of the pellets and cellulase production by T. reesei. The findings from this study can be used for improvement of cellulase productivity.  相似文献   
999.
研究农田土壤酶活性对CO2浓度升高和增温的响应,可为气候变化背景下农田生态系统养分管理提供科学依据。本研究在人工模拟气候室进行盆栽控制试验,设置了4种气候情景,分别为对照(CK,CO2浓度400 μmol·mol-1+正常环境温度)、CO2浓度升高(ECO2,CO2浓度800 μmol·mol-1+正常环境温度)、增温(ET,CO2浓度400 μmol·mol-1+增温4 ℃)及CO2浓度和温度均升高(ECO2+T,CO2浓度800 μmol·mol-1+增温4 ℃),研究有、无冬小麦生长下β--葡萄糖苷酶(βG)、β-N-乙酰葡糖苷酶(NAG)、碱性磷酸单脂酶(ALP)和多酚氧化酶(PPO)4种土壤酶活性在冬小麦拔节期(JS)、开花期(AS)、灌浆期(FS)和成熟期(MS)对CO2浓度升高和增温的响应。结果表明:无冬小麦生长下,ECO2与CK间4种土壤酶活性差异不显著,而ET和ECO2+T处理对4种土壤酶活性有显著抑制作用。有冬小麦生长条件下,与CK相比,ECO2和ECO2+T处理对4种土壤酶活性均无显著影响;ET处理对土壤ALP和PPO活性有显著影响;ECO2+T与ET间4种土壤酶活性有显著差异,与ET相比,ECO2+T处理的土壤βG活性在JS期显著增加,NAG活性在JS期显著降低,ALP活性在AS和FS期显著增加,PPO活性在JS期显著降低,而在AS期显著增加。CO2浓度升高与增温的交互作用在有、无冬小麦生长下均对土壤NAG和ALP活性有显著影响;无冬小麦生长下,增温和试验时段的交互作用对4种土壤酶活性有显著影响,而在有冬小麦生长下,增温和生育期的交互作用仅对ALP和PPO活性有显著影响;CO2浓度升高、增温与试验时段的交互作用在无冬小麦生长下对土壤βG、ALP和PPO活性有显著影响,而在有冬小麦生长下CO2浓度升高、增温与生育期对土壤NAG、ALP和PPO活性有显著影响。冬小麦生长对土壤βG、NAG和ALP活性在前两个生育期(JS+AS期)表现为显著抑制作用,在后两个生育期(FS+MS期)表现为显著促进作用,对土壤PPO活性在全生育期均表现为显著抑制作用。总体上,CO2浓度升高对冬小麦土壤酶活性的影响不显著,而CO2浓度与温度均升高对冬小麦土壤酶活性的影响在不同生育期因土壤酶种类不同而不同;此外,有、无冬小麦条件下4种土壤酶活性对CO2浓度升高与增温的交互作用响应程度不一。  相似文献   
1000.
新桑树品种——川826的育成   总被引:2,自引:0,他引:2  
经多年观察比较,新桑品种“川826”表现出遗传性状稳定、优质、高产、抗性较好等优点,2000年正式列为“十五”省农作物育种攻关项目“优质、高产桑、蚕新品种选育”中桑主攻品种,并进一步进行区域性比较试验。经过2002年至2005年在四川省乐山、三台、蚕研所等三点的比较试验和在四川篷安生产示范点的示范繁殖,“川826”与对照品种“湖32”相比,其产叶量高13.95%,万头产茧量高8.88%,万头产茧层量高8.8%,五龄担桑产茧量高13.51%,667 m2(亩)桑产茧量高28.2%,桑产茧层量高27.6%。特别是用“川826”桑叶养蚕后产卵制种成绩尤为突出,单蛾产卵量比对照高6.87%以上,单蛾正常卵粒数比对照高5.63%以上。2006年4月被四川省农作物品种审定委员会审定为合格品种。  相似文献   
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