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991.
The β3 adrenergic receptor (ADRB3) plays a critical role in the regulation of energy metabolism in mammals. In sheep, intronic polymorphism of the ADRB3 gene has been associated with lamb survival and various production traits. This study investigates variation in the ovine ADRB3 3' untranslated region (3'UTR), a region that may impact expression of the gene. Using PCR- single strand conformational polymorphism (SSCP), six unique patterns (named a-f) were observed in an approximately 304-bp amplicon. Sequencing revealed three single-nucleotide polymorphisms (c.*233A>C, c.*271G>C, c.*357A>T) and a single-nucleotide deletion (c.*257delG). Haplotype analyses showed that the previously described allele A defined by variation in the ovine ADRB3 intron can be divided into three haplotypes (Aa, Ab, and Ac). In total, 16 haplotypes through ovine ADRB3 were detected. This study suggests that ovine ADRB3 is highly polymorphic and that the extended haplotype analysis through the promoter, 5'UTR, coding sequence, intron, and 3'UTR needs to be performed to define the full extent of variation in this gene.  相似文献   
992.
Thirteen novel seco-DCK analogs (416) with several new skeletons were designed, synthesized and screened for in vitro anti-HIV-1 activity. Among them, three compounds (5, 13, and 16) showed moderate activity, and compound 9 exhibited the best activity with an EC50 value of 0.058 μM and a therapeutic index (TI) of 1000. The activity of 9 was better than that of 4-methyl DCK (2, EC50: 0.126 μM, TI: 301.2) in the same assay. Additionally, 9 also showed antiviral activity against a multi-RT inhibitor-resistant strain (RTMDR), which is insensitive to most DCK analogs. Compared with 2, compound 9 has a less complex structure, fewer hydrogen-bond acceptors, and a reduced log P value. Therefore, it is likely to exhibit better ADME, and appears to be a promising new lead for further development as an anti-HIV candidate.  相似文献   
993.
994.
2,3-Diaminopropionic acid (Dap) and N-terminal Dap peptides have been found to inhibit in vitro protein-modifications by methylglyoxal (MG), one of the highly reactive α-dicarbonyl compounds. MG scavenging potency of the newly synthesized N-terminal Dap peptides is demonstrated by RP-HPLC, SDS–PAGE and non-denaturing PAGE analysis, assays for enzymatic activity and cell viability study and was compared with that of known AGE inhibitors, such as aminoguanidine, pyridoxamine, metformin and carnosine. Two addition products of MG and l-Dap-l-Leu are separated by HPLC and their chemical structures are characterized by 1H and 13C NMR spectroscopy to indicate that both of them are pyrazines derived from 2 molecules of MG and 1 molecule of l-Dap-l-Leu. Mutagenic activities of l-Dap-l-Leu and l-Dap-l-Val and their metabolites according to the Ames assay are found to be negative.  相似文献   
995.
996.
997.
Publicly-accessible resources have promoted the advance of scientific discovery. The era of genomics and big data has brought the need for collaboration and data sharing in order to make effective use of this new knowledge. Here, we describe the web resources for cancer genomics research and rate them on the basis of the diversity of cancer types, sample size, omics data comprehensiveness, and user experience. The resources reviewed include data repository and analysis tools; and we hope such introduction will promote the awareness and facilitate the usage of these resources in the cancer research community.  相似文献   
998.
The aerial parts of higher plants are generated from the shoot apical meristem(SAM). In this study, we isolated a small rice(Oryza sativa L.) mutant that showed premature termination of shoot development and was named mini rice 1(mini1). The mutant was first isolated from a japonica cultivar Zhonghua11(ZH11) subjected to ethyl methanesulfonate(EMS)treatment. With bulked segregant analysis(BSA) and map-based cloning method, Mini1 gene was finally fine-mapped to an interval of 48.6 kb on chromosome 9. Sequence analyses revealed a single base substitution from G to A was found in the region, which resulted in an amino acid change from Gly to Asp.The candidate gene Os09g0363900 was predicted to encode a putative adhesion of calyx edges protein ACE(putative HOTHEAD precursor) and genetic complementation experiment confirmed the identity of Mini1. Os09g0363900 contains glucose-methanol-choline(GMC) oxidoreductase and NAD(P)-binding Rossmann-like domain, and exhibits high similarity to Arabidopsis HOTHEAD(HTH). Expression analysis indicated Mini1 was highly expressed in young shoots but lowly in roots and the expression level of most genes involved in auxin biosynthesis and signal transduction were reduced in mutant.We conclude that Mini1 plays an important role in maintaining SAM activity and promoting shoot development in rice.  相似文献   
999.
目的:研究Rac1和Cdc42在人乳腺癌中的表达及临床意义。方法:收集339例人乳腺癌组织样本,通过免疫组化的方法检测Rac1和Cdc42的表达情况,并分析其与乳腺癌临床病理学特征间的相关性。结果:Rac1和Cdc42在正常乳腺组织中几乎不表达,而在肿瘤组织的阳性表达率分别为35.9%和38.5%,均较正常乳腺组织显著升高,差异均具有统计学意义(P0.001和P0.05)。卡方检验分析表明,二者的表达与患者的年龄、肿瘤大小、组织分化程度、HER2状态无关(P0.05),而与TNM分期、淋巴结转移、肿瘤侵袭、ER状态和Ki-67表达有相(P0.05)。相关性分析表明,Rac1和Cdc42的表达与高TNM分期(r分别为0.443和0.295;P均0.001)、淋巴结转移阳性(r均为0.480和0.562;P均0.001)、肿瘤侵袭(r分别为0.412和0.440;P均0.001)、ER阴性表达(r分别为-0.517和-0.342;P均0.001)以及Ki-67高表达(r分别为0.338和0.454;P均0.001)呈正相关。结论:在乳腺癌组织中,Rac1和Cdc42作为癌基因表达增加,可能在乳腺癌恶性进程中发挥重要作用。  相似文献   
1000.
BackgroundLittle is known regarding the effects of environmental exposure of chemicals on androgenic system in the general population. We studied 5,107 subjects included in the National Health and Nutrition Examination Survey (2011–2012).MethodsUrinary, serum, and blood levels of 15 subclasses comprising 110 individual chemicals were analyzed for their association with serum testosterone levels. The subjects were divided into high and low testosterone groups according to the median testosterone concentration (374.51 ng/dL). Odds ratios (ORs) of individual chemicals in association with testosterone were estimated using logistic regression after adjusting for age, ethnicity, cotinine, body mass index, creatinine, alcohol, and the poverty income ratio.ResultsAdjusted ORs for the highest versus lowest quartiles of exposure were 2.12 (95% CI: 1.07, 4.21; Ptrend = 0.044), 1.84 (95% CI: 1.02, 3.34; Ptrend = 0.018) for the association between urinary mandelic acid, and strontium quartiles with low testosterone concentrations in adult men, respectively. However, no association was observed for the remaining chemicals with testosterone.ConclusionsThe National Health and Nutrition Examination Survey data suggest that elevations in urinary mandelic acid, and strontium levels are negatively related to low serum testosterone levels in adult men.  相似文献   
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