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排序方式: 共有9227条查询结果,搜索用时 15 毫秒
961.
Yu Xue Qingmei Xie Zhuanqiang Yan Jun Ji Feng Chen Jianping Qin Baoli Sun Jingyun Ma Yingzuo Bi 《Journal of virology》2012,86(24):13812-13813
Recently, nephropathogenic infectious bronchitis virus (IBV) outbreaks have occurred in commercial broiler flocks and have been associated with a high incidence and morbidity in China. The CK/CH/Zhejiang/06/10 strain (IBV-YX10) was isolated from a 12-day-old broiler chicken in a flock of chickens with swollen speckled kidneys and distended ureters filled with uric acid in China in 2010. Here we reported the complete genomic sequence of the IBV-YX10 which was a natural recombinant nephropathogenic infectious bronchitis virus strain. These findings will contribute additional insights into the molecular characteristics of evolving IBV genomes and the need for effective control of IBV in China. 相似文献
962.
963.
Yuan Z Chu G Dan Y Li J Zhang L Gao X Gao H Li J Xu S Liu Z 《Molecular biology reports》2012,39(6):6625-6631
Bovine mastitis is a very complex and common disease of dairy cattle and a major source of economic losses to the dairy industry
worldwide. In this study, the bovine breast cancer 1, early onset gene (BRCA1) was taken as a candidate gene for mastitis resistance. The main object of this study was to investigate whether the BRCA1 gene was associated with mastitis in cattle. Through DNA sequencing, Polymerase Chain Reaction-Restriction Fragment Length
Polymorphism (PCR-RFLP) and Created Restriction Site PCR (CRS-PCR) methods, three SNPs (G22231T, T25025A, and C28300A) were
detected and twenty-four combinations of these SNPs were observed. The single SNP and their genetic effects on somatic cell
score (SCS) were evaluated and a significant association with SCS was found in C28300A. The mean of genotype EE was significantly
lower than those of genotypes EF and FF. The results of combined genotypes analysis of three SNPs showed that BBDDFF genotype
with the highest SCS were easily for the mastitis susceptibility, whereas AACCEE genotype with the lowest SCS were favorable
for the mastitis resistance. The information provided in the present study will be very useful for improving mastitis resistance
in dairy cattle by marker-assisted selection. 相似文献
964.
CD40 signaling plays a critical role in the survival rate of gastric cancer patients. Tumour samples were collected from 73 patients with who were diagnosed as gastric cancer in general surgery department in the 1st affiliated hospital of Suzhou University between September 2002 and July 2003. All patients had not received radiotherapy and chemotherapy before operation. These patients include 46 male and 27 female. Here we show that CD40 is constitutively expressed in the human gastric carcinoma tissues, and CD40 protein and mRNA positive expression in gastric cancer tissues closely correlated with lymph node metastasis and tumour TNM stage. CD40 positive expression in gastric cancer patients with lymph node metastasis was markedly higher than that in gastric cancer patients without lymph node metastasis. CD40 positive expression in stage III-IV gastric cancer patients was markedly higher than that in stage I-II gastric cancer patients. Moreover, CD40 expression closely correlated with prognosis of gastric cancer patients. Therefore, CD40 was taken as grouping variable, and lymph node metastasis and clinical staging were taken as stratification variables, respectively, further analysis showed that prognosis in gastric cancer patients with lymph node metastasis and CD40 positive expression was markedly worse than that in gastric cancer patients without lymph node metastasis and CD40 negative expression (P = 0.0076). These results suggest that CD40 signaling plays a critical role in the survival of gastric cancer patients. 相似文献
965.
966.
967.
We evaluated the association between GSTM1 and GSTT1 gene polymorphisms and susceptibility to chronic obstructive pulmonary
disease (COPD) in smokers. A meta-analysis of the published case–control studies was performed. Published literature was retrieved
from PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI), with last update in February, 2011. Data were extracted
and a fixed- or random-effects model was used to calculate pooled odds ratios with 95% confidence intervals depending on statistical
heterogeneity. Fourteen eligible studies, comprising 1,665 COPD cases and 1,614 controls, were included in the meta-analysis.
The combined analyses showed that there was a significant difference in GSTM1 genotype distribution between COPD cases and
controls among Caucasians, but not among Asians. The combined GSTM1/GSTT1 null genotype conferred a 1.36-fold greater risk
for COPD in Asian smokers. The GSTT1 null genotype alone was not associated with enhanced risk for COPD. The GSTM1 null genotype
is significantly associated with an increasing susceptibility to COPD in Caucasian smokers, but not in Asian smokers. The
GSTM1/GSTT1 null genotype is a significant risk factor for developing COPD in Asian smokers. The GSTT1 null genotype, however,
was not associated with COPD. 相似文献
968.
969.
Li S Jiang J Zou J Qiao J Xue S Wei L Long R Wang L Castiblanco A White N Ngo J Mao H Liu ZR Yang JJ 《Journal of inorganic biochemistry》2012,107(1):111-118
Magnetic resonance imaging (MRI) has emerged as a leading diagnostic technique in clinical and preclinical settings. However, the application of MRI to assess specific disease markers for diagnosis and monitoring drug effect has been severely hampered by the lack of desired contrast agents with high relaxivities, and optimized in vivo retention time. We have reported the development of protein-based MRI contrast agents (ProCA1) by rational design of Gd3 + binding sites into a stable protein resulting in significantly increased longitudinal (r1) and transverse (r2) relaxivities compared to Gd-DTPA. Here, we report a further improvement of protein contrast agents ProCA1 for in vivo imaging by protein modification with various sizes of polyethylene glycol (PEG) chain. PEGylation results in significant increases of both r1 and r2 relaxivities (up to 200%), and these high relaxivities persist even at field strengths up to 9.4 T. In addition, our experimental results demonstrate that modified contrast agents have significant improvement of in vivo MR imaging and biocompatibilities including dose efficiency, protein solubility, blood retention time and decreased immunogenicity. Such improvement can be important to the animal imaging and pre-clinical research at high or ultra-high field where there is an urgent need for molecular imaging probes and optimized contrast agent. 相似文献
970.
Adsorption–desorption of iodine in two forms, viz., iodide (I−) and iodate (IO3−), in three types of soil were investigated. The soils were: red soil developed on Quaternary red earths (REQ)— clayey, kaolintic
thermic plinthite Aquult, Inceptisol soil (IS) and alluvial soil (AS)—Fluvio-marine yellow loamy soil. The isothermal curves
of iodine adsorption on soils were described by Langmuir and Freundlich equation, and the maximum adsorption values (y
m) were obtained from the simple Langmuir model. As compared with the iodide, the iodate was adsorbed in higher amounts by
the soils tested. Among three soils, the REQ soil adsorbed more iodine (I− and IO3−) than the IS and AS. The distribution coefficient (K
d) of iodine in the soils decreased exponentially with increasing iodine loading concentration. Desorption of iodine in soil
was increased correspondingly with increasing adsorption values. The REQ soil had a greater affinity for iodine than the IS
and AS at the same iodine loadings. In the pot experiment cultivated with pakchoi (Brassica chinensis L.) and added with two exogenous iodine sources, the iodide form was quickly taken up by pakchoi and caused more toxicity
to the vegetable. The rate of iodine loss from soil was higher for iodide form as compared with the iodate. The iodine bioavailability
was the highest but the persistence was the weakest in AS among the three soils tested, and the REQ soil showed just the opposite
trend to that of the AS soil. This study is of theoretical importance to understand the relationship between iodine adsorption–desorption
characteristics and their bioavailability in different soils and it also has practical implications for seeking effective
alternatives of iodine biofortification to prevent iodine deficiency disorders. 相似文献