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991.
间歇性低氧对肥胖小鼠瘦素及其受体表达的影响   总被引:3,自引:0,他引:3  
Qin L  Song Z  Wen SL  Jing R  Li C  Xiang Y  Qin XQ 《生理学报》2007,59(3):351-356
为探讨适度低氧环境对体重的影响及其作用机制,明确瘦素在其中的作用,用高脂饮食建立小鼠肥胖模型并观察间歇性低氧的干预效果。健康昆明小鼠随机分为4组(每组20只),正常对照组:喂正常食物,不进行间歇性低氧训练;低氧组:喂正常食物,并进行间歇性低氧训练;肥胖组:喂高脂、高糖食物,但不进行间歇性低氧训练;低氧+肥胖组,喂高脂、高糖食物,并进行间歇性低氧训练。40d后,测量小鼠体重,用酶联免疫吸附法测定血清瘦素水平,免疫组织化学检测肝脏瘦素受体表达,苏丹Ⅲ染色检测肝脏脂肪细胞分布和密度。结果显示,与正常对照组相比,肥胖组小鼠平均体重和平均血清瘦素水平显著升高,肝脏分布大量脂肪细胞,提示高脂模型建立成功;经过间歇性低氧训练后,低氧组和低氧+肥胖组小鼠的平均体重及肝脏脂肪细胞分布密度和范围分别较对照组和肥胖组低,而血清瘦素水平明显增高;低氧+肥胖组小鼠肝脏瘦素受体的表达高于肥胖组。结果提示,适度的间歇性低氧可以通过提高血清瘦素水平和增强肝脏瘦素受体表达而使体重减轻,并有效防止肝细胞脂肪变。  相似文献   
992.
NYD-SP12 is a recently identified spermatogenesis-related gene with a pivotal role in human testis development. In this study, we analyzed between-species divergence and within-species variation of NYD-SP12 in seven representative primate species, four worldwide human populations, and 124 human clinical subjects. Our results indicate that NYD-SP12 evolves rapidly in both the human and the chimpanzee lineages, which is likely caused by Darwinian positive selection and/or sexual selection. We observed significant interpopulation divergence among human populations, which might be due to the varied demographic histories. In the association analysis, we demonstrated significant frequency discrepancy of a synonymous sequence polymorphism among the clinical groups with different sperm traits. [Reviewing Editor: Dr. Manyuan Long]  相似文献   
993.
Mucosa-associated microbiota from different regions of the gastrointestinal (GI) tract of adult broilers was studied by analysis of 16S rRNA gene sequences. The microbiota mainly comprised Gram-positive bacteria along the GI tract. Fifty-one operational taxonomic units (OTUs) (from 98 clones) were detected in the ceca, as compared with 13 OTUs (from 49 clones) in the crops, 11 OTUs (from 51 clones) in the gizzard, 14 OTUs (from 52 clones) in the duodenum, 12 OTUs (from 50 clones) in the jejunum and nine OTUs (from 50 clones) in the ileum. Ceca were dominantly occupied by clostridia-related sequences (40%) with other abundant sequences being related to Faecalibacterium prausnitzii (14%), Escherichia coli (11%), lactobacilli (7%) and Ruminococcus (6%). Lactobacilli were predominant in the upper GI tract and had the highest diversity in the crop. Both Lactobacillus aviarius and Lactobacillus salivarius were the predominant species among lactobacilli. Candidatus division Arthromitus was also abundant in the jejunum and ileum.  相似文献   
994.
995.
对神农架大九湖湿地泥炭资源进行了调查、采样、检测与评价。结果表明,神农架泥炭中,有机质含量>70%,腐殖酸含量>30%,胡敏酸与富里酸的含量比C(胡敏酸)/C(富里酸)>5.0,水解氨基酸含量为7%。可用于医药、保健、增效、添加等系列生物制品的开发。  相似文献   
996.
A Gram-negative bacillus, SMC-6271(T), which was isolated from the bone marrow of a patient with leukemia but could not be identified by a conventional microbiologic method, was characterized by a genotypic analysis of 16S rRNA gene. Sequences of the 16S rRNA gene revealed that this bacterium was closely related to Tepidimonas ignava and other slightly thermophilic isolates but diverged distinctly from them. Analyses of cellular fatty acid composition and performance of biochemical tests confirmed that this bacterium is a distinct species from the other Tepidimonas species. Based on the evaluated phenotypic and genotypic characteristics, it is proposed that SMC-6271T (=ABB 0301T =KCTC 12412T =JCM 13232T) should be classified as a new species, namely Tepidimonas arfidensis sp. nov.  相似文献   
997.
Overall survival of patients with low-grade glioma (LGG) has shown no significant improvement over the past 30 years, with survival averaging approximately 7 years. This study aimed to identify novel promising biomarkers of LGG and reveal its potential molecular mechanisms by integrated bioinformatics analysis. The microarray datasets of GSE68848 and GSE4290 were selected from GEO database for integrated analysis. In total, 293 overlapping differentially expressed genes (DEGs) were detected using the limma package. One hundred and eighty-eight nodes with 603 interactions were obtained from the establishment of protein-protein interaction (PPI) network. Functional and signaling pathway enriched were significantly correlated with the synapse and calcium signaling pathway, respectively. Module analysis revealed eight hub genes with high connectivity, which included CHRM1, DLG2, GABRD, GRIN1, HTR2A, KCNJ3, KCNJ9, and NUSAP1, and they were markedly correlated with patients’ prognosis. The mining of the Gene Expression Profiling Interactive Analysis database and qPCR further confirmed the abnormal expression of these key genes with their prognostic value in LGG. We eventually predicted the 20 most vital small molecule drugs, which potentially reverse the carcinogenic state of LGG, as per the CMap (connectivity map) database and these DEGs, and MS-275 (enrichment score = −0.939) was considered as the most promising small molecule to treat LGG. In conclusion, our study provided eight reliable novel molecular biomarkers for diagnosis, prognosis prediction, and treatment targets for LGG. These conclusions will contribute to a better comprehension of molecular mechanisms fundamental to LGG occurrence and progression, and providing new insights for future development of genomic individualized treatment in LGG.  相似文献   
998.
Fibrillar protein aggregates (amyloids) are involved in several common pathologies, e.g., Alzheimer's disease and type II diabetes. Accumulating evidence suggests that toxicity in amyloid-related diseases originates from the deposition of protein aggregates on the cell membrane, which results in bilayer disruption and cell leakage. The molecular mechanism of damage to the membrane, however, is still obscure. To shed light on it we have performed coarse-grained molecular dynamics simulations of fibril-forming amphipathic peptides in the presence of lipid vesicles. The simulation results show that highly amyloidogenic peptides fibrillate on the surface of the vesicle, damaging the bilayer and promoting leakage. In contrast, the ordered aggregation of peptides with low amyloidogenicity is hindered by the vesicles. Remarkably, leakage from the vesicle is caused by growing aggregates, but not mature fibrils. The simulation results provide a basis for understanding the range of aggregation behavior that is observed in experiments with fibril-forming (poly)peptides.  相似文献   
999.
The length–weight relationships (LWRs) were analyzed for three fish species collected from Beibu Gulf between October 2012 and March 2013. The study used bottom trawl with 40 mm mesh size. The values of parameter b varied from 2.8495 to 3.0277.  相似文献   
1000.
目的:探讨徒手淋巴引流对全膝关节置换术(TKA)后肢体肿胀程度及血液炎性指标的影响。方法:选取2018年12月~2019年12月广东省中医院珠海医院收治的拟行初次TKA手术的膝骨关节炎(KOA)患者70例,随机分为观察组和对照组各35例,对照组按TKA术后常规方案治疗,观察组在对照组基础上增加徒手淋巴引流术,比较两组术前,术后1 d、4 d、7 d、2周、4周、8周肤温、肿胀程度及血液炎性指标,评估患者术后康复情况及不良事件发生情况。结果:两组术后2周肤温低于术后7 d,术后4周低于术后2周,术后8周低于术后4周,差异均有统计学意义(P0.05)。观察组术后2周、4周、8周肤温均低于对照组,差异均有统计学意义(P0.05)。两组术后1 d肢体肿胀度低于术后4 d,术后2周低于术后7 d,术后4周低于术后2周,术后8周低于术后4周,差异均有统计学意义(P0.05)。观察组术后7d、2周、4周、8周肢体肿胀度均低于对照组,差异均有统计学意义(P0.05)。两组术后4 d白细胞计数(WBC)水平低于术后1 d,而超敏C反应蛋白(hs-CRP)水平高于术后1 d;两组术后7 d WBC、hs-CRP及血沉(ESR)水平均低于术后4 d,且术后2周低于术后7 d,术后4周低于术后2周,术后8周低于术后4周,差异均有统计学意义(P0.05)。观察组术后7 d hs-CRP水平均低于对照组,术后2周、4周、8周hs-CRP、ESR水平均低于对照组,差异均有统计学意义(P0.05)。结论:TKA术后应用徒手淋巴引流手法能有效减轻患者术后肢体肿胀程度,缩短炎症周期,降低炎症反应,在临床上值得推广应用。  相似文献   
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