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111.
《Microbes and infection / Institut Pasteur》2022,24(2):104892
Gut microbiota is believed to play a crucial role in obesity. However, the consistent findings among published studies regarding microbiome–obesity interaction are relatively rare, and one of the underlying causes could be the limited sample size of cohort studies. In order to identify gut microbiota changes between normal-weight individuals and obese individuals, fecal samples along with phenotype information from 2262 Chinese individuals were collected and analyzed. Compared with normal-weight individuals, the obese individuals exhibit lower diversity of species and higher diversity of metabolic pathways. In addition, various machine learning models were employed to quantify the relationship between obesity status and Body mass index (BMI) values, of which support vector machine model achieves best performance with 0.716 classification accuracy and 0.485 R2 score. In addition to two well-established obesity-associated species, three species that have potential to be obesity-related biomarkers, including Bacteroides caccae, Odoribacter splanchnicus and Roseburia hominis were identified. Further analyses of functional pathways also reveal some enriched pathways in obese individuals. Collectively, our data demonstrates tight relationship between obesity and gut microbiota in a large-scale Chinese population. These findings may provide potential targets for the prevention and treatment of obesity. 相似文献
112.
《遗传学报》2022,49(11):1042-1052
Advanced maternal age is characterized by declines in the quantity and quality of oocytes in the ovaries, and the aging process is accompanied by changes in gut microbiota composition. However, little is known about the relationship between gut microbiota and ovarian aging. By using fecal microbiota transplantation (FMT) to transplant material from young (5-week-old) into aged (42-week-old) mice, we find that the composition of gut microbiota in FMT-treated mice presents a “younger-like phenotype” and an increase of commensal bacteria, such as Bifidobacterium and Ruminococcaceae. Moreover, the FMT-treated mice show increased anti-inflammatory cytokine IL-4 and decreased pro-inflammatory cytokine IFN-γ. Fertility tests for assessing ovarian function reveal that the first litter size of female FMT-treated mice is significantly higher than that of the non-FMT group. Morphology analysis demonstrates a dramatic decrease in follicle atresia and apoptosis as well as an increase in cellular proliferation in the ovaries of the FMT-treated mice. Our results also show that FMT improves the immune microenvironment in aged ovaries, with decreased macrophages and macrophage-derived multinucleated giant cells (MNGCs). These results suggest that FMT from young donors could be a good choice for delaying ovarian aging. 相似文献
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115.
Yang Wang 《Bioscience, biotechnology, and biochemistry》2019,83(5):914-922
This study aimed to evaluate the microbial compositions and gene expression related to inflammation in dextran sodium sulfate (DSS)-induced acute colitis and the effect of mulberry supplementation. Male BALB/c mice received a diet supplemented with mulberry juice freeze-dried powder (MFP) or not for 3 weeks. After 3 weeks, the mice received water containing 5% (w/v) DSS or not for 1 week. The disease activity index score in mice fed MFP was significantly decreased. A significant decrease in Bifidobacterium spp. and the Clostridium perfringens subgroup was observed in mice not fed MFP. The number of goblet cell and NLRP6 expression were observed in mice fed a diet supplemented with MFP compared with mice not fed MFP. These results may indicate that mulberry mitigates DSS-induced acute colitis by a changing the gut microbial flora and by improving mucosal conditions. 相似文献
116.
The increased prevalence of type 2 diabetes mellitus (T2DM) and life expectancy of diabetic patients fosters the worldwide prevalence of retinopathy and nephropathy, two major microvascular complications that have been difficult to treat with contemporary glucose-lowering medications. The gut microbiota (GM) has become a lively field research in the last years; there is a growing recognition that altered intestinal microbiota composition and function can directly impact the phenomenon of ageing and age-related disorders. In fact, human GM, envisaged as a potential source of novel therapeutics, strongly modulates host immunity and metabolism. It is now clear that gut dysbiosis and their products (e.g. p-cresyl sulfate, trimethylamine?N?oxide) dictate a secretory associated senescence phenotype and chronic low-grade inflammation, features shared in the physiological process of ageing (“inflammaging”) as well as in T2DM (“metaflammation”) and in its microvascular complications. This review provides an in-depth look on the crosstalk between GM, host immunity and metabolism. Further, it characterizes human GM signatures of elderly and T2DM patients. Finally, a comprehensive scrutiny of recent molecular findings (e.g. epigenetic changes) underlying causal relationships between GM dysbiosis and diabetic retinopathy/nephropathy complications is pinpointed, with the ultimate goal to unravel potential pathophysiological mechanisms that may be explored, in a near future, as personalized disease-modifying therapeutic approaches. 相似文献
117.
Kundan Kumar Gaurao V. Dhoke Ashok K. Sharma Shubham K. Jaiswal Vineet K. Sharma 《Journal of cellular biochemistry》2019,120(7):11206-11215
The human gut harbors diverse bacterial species in the gut, which play an important role in the metabolism of food and host health. Recent studies have also revealed their role in altering the pharmacological properties and efficacy of oral drugs through promiscuous metabolism. However, the atomistic details of the enzyme-drug interactions of gut bacterial enzymes which can potentially carry out the metabolism of drug molecules are still scarce. A well-known example is the FDA drug amphetamine (a central nervous system stimulant), which has been predicted to undergo promiscuous metabolism by gut bacteria. Therefore, to understand the atomistic details and energy landscape of the gut microbial enzyme-mediated metabolism of this drug, molecular dynamics studies were performed. It was observed that amphetamine binds to tyramine oxidase from the Escherichia coli strain present in the human gut microbiota at the binding site harboring polar and nonpolar amino acids. The stability analysis of amphetamine at the binding site showed that the binding is stable and the free energy for the binding of amphetamine was found to be ~ −51.71 kJ/mol. The insights provided by this study on promiscuous metabolism of amphetamine by a gut enzyme will be very useful to improve the efficacy of the drug. 相似文献
118.
Bing Wei Yi Chen Tingyan Lu Wenjiao Cao Zhenhua Tang Haiou Yang 《Genetics and molecular biology》2022,45(2)
The process from high-risk human papillomavirus (HR-HPV) infection to cervical cancer is a continuous and long-term process, but the pathogenesis of the whole process is not completely clear. Here, 59 Chinese women were engaged in this study, and divided into five groups: normal healthy group, HR-HPV infections group, low-grade intraepithelial neoplasia (LSIL) group, high-SIL(HSIL) group, and cervical cancer group. With the occurrence of HR-HPV infection and the development of cervical lesions, the diversity of vaginal microbiota species was increased, and the relative abundance of Lactobacillus (L.), the dominant bacteria in maintaining vaginal microecological balance, was decreased gradually. In contrast, the abundance of Actinobacteria in the four disease groups was significantly higher than that in normal group. Furthermore L. iners may be related to the serious progression of cervical cancer. After analyzing the whole process, we found that Gardnerella(G.), Atopobium(A.) and Dialister(D.) have important effects on both persistent HR-HPV infection and the pathogenesis of cervical cancer. In addition, PICRUSt2 and KEGG results showed that the KEGG pathways enriched by the predicted genes of vaginal microbiota in cancer group included metabolic diseases, endocrine system and immune systems when compared with that in normal group. These findings may provide insights into the pathogenesis of cervical cancer, and help to improve the early detection and prevention of cervical precancerous lesions. 相似文献
119.
近年来得益于宏基因组学和代谢组学研究技术的进步,人类健康或疾病状态下,肠道菌群与宿主相关性研究剧增,但其潜在机制研究仍然处于初级阶段。以慢性肾脏病(chronic kidney disease, CKD)为研究背景,大量证据表明患者宿主和肠道菌群之间存在双向关联。一方面,CKD的病理状态下存在特殊的肠道菌群代谢模式;另一方面,肠道菌群紊乱及分解代谢后产生的肠源性尿毒症毒素(gut-derived uremic toxins, GDUT)也加速CKD进展。因此,本文着重探讨硫酸吲哚酚、硫酸对甲酚和氧化三甲胺等关键GDUT对CKD患者结肠转运时间、肾转运体和自清除作用的潜在作用机制。进而从微生态角度出发,提出优化膳食摄入、调节肠道菌群等肾保护性措施,为延缓CKD的进展提供新的治疗思路。 相似文献
120.
Sara Santarossa Alexandra R. Sitarik Christine Cole Johnson Jia Li Susan V. Lynch Dennis R. Ownby Alex Ramirez Germaine LM. Yong Andrea E. Cassidy-Bushrow 《Journal of Exercise Nutrition & Biochemistry》2021,25(4):24
[Purpose] To determine whether physical activity (PA), primarily the recommended 60 minutes of moderate-to-vigorous PA, is associated with gut bacterial microbiota in 10-year-old children.[Methods] The Block Physical Activity Screener, which provides minutes/day PA variables, was used to determine whether the child met the PA recommendations. 16S rRNA sequencing was performed on stool samples from the children to profile the composition of their gut bacterial microbiota. Differences in alpha diversity metrics (richness, Pielou’s evenness, and Faith’s phylogenetic diversity) by PA were determined using linear regression, whereas beta diversity (unweighted and weighted UniFrac) relationships were assessed using PERMANOVA. Taxon relative abundance differentials were determined using DESeq2.[Results] The analytic sample included 321 children with both PA and 16S rRNA sequencing data (mean age [SD] =10.2 [0.8] years; 54.2% male; 62.9% African American), where 189 (58.9%) met the PA recommendations. After adjusting for covariates, meeting the PA recommendations as well as minutes/day PA variables were not significantly associated with gut richness, evenness, or diversity (p ≥ 0.19). However, meeting the PA recommendations (weighted UniFrac R2 = 0.014, p = 0.001) was significantly associated with distinct gut bacterial composition. These compositional differences were partly characterized by increased abundance of Megamonas and Anaerovorax as well as specific Christensenellaceae_R-7_group taxa in children with higher PA.[Conclusion] Children who met the recommendations of PA had altered gut microbiota compositions. Whether this translates to a reduced risk of obesity or associated metabolic diseases is still unclear. 相似文献