全文获取类型
收费全文 | 4355篇 |
免费 | 280篇 |
国内免费 | 6篇 |
出版年
2024年 | 4篇 |
2023年 | 15篇 |
2022年 | 38篇 |
2021年 | 91篇 |
2020年 | 48篇 |
2019年 | 80篇 |
2018年 | 114篇 |
2017年 | 104篇 |
2016年 | 168篇 |
2015年 | 212篇 |
2014年 | 275篇 |
2013年 | 316篇 |
2012年 | 386篇 |
2011年 | 393篇 |
2010年 | 212篇 |
2009年 | 208篇 |
2008年 | 307篇 |
2007年 | 253篇 |
2006年 | 191篇 |
2005年 | 187篇 |
2004年 | 181篇 |
2003年 | 185篇 |
2002年 | 139篇 |
2001年 | 125篇 |
2000年 | 107篇 |
1999年 | 76篇 |
1998年 | 34篇 |
1997年 | 20篇 |
1996年 | 31篇 |
1995年 | 17篇 |
1994年 | 13篇 |
1993年 | 12篇 |
1992年 | 26篇 |
1991年 | 25篇 |
1990年 | 10篇 |
1989年 | 14篇 |
1988年 | 8篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有4641条查询结果,搜索用时 123 毫秒
981.
Sang-Nam?Kim Young-Suk?Jung Hyun-Jung?Kwon Je?Kyung?Seong James?G.?Granneman Yun-Hee?LeeEmail authorView authors OrcID profile 《Biology of sex differences》2016,7(1):67
Background
The higher prevalence of obesity-related metabolic disease in males suggests that female sex hormones provide protective mechanisms against the pathogenesis of metabolic syndrome. Because browning of white adipose tissue (WAT) is protective against obesity-related metabolic disease, we examined sex differences in β3-adrenergic remodeling of WAT in mice.Methods
Effects of the β3-adrenergic receptor agonist CL316,243 (CL) on browning of white adipose tissue were investigated in male and female C57BL mice. The role of ovarian hormones in female-specific browning was studied in control female C57BL mice and mice with ovarian failure induced by 4-vinylcyclohexene diepoxide treatment for 15 days.Results
We found that treatment with CL-induced upregulation of brown adipocyte markers and mitochondrial respiratory chain proteins in gonadal WAT (gWAT) of female mice, but was without effect in males. In contrast, CL treatment was equally effective in males and females in inducing brown adipocyte phenotypes in inguinal WAT. The tissue- and sex-specific differences in brown adipocyte recruitment were correlated with differences in sympathetic innervation, as determined by tyrosine hydroxylase immunostaining and western blotting. Levels of the neurotrophins NGF and BDNF were significantly higher in gWAT of female mice. CL treatment significantly increased NGF levels in gWAT of female mice but did not affect BDNF expression. In contrast, estradiol treatment doubled BDNF expression in female adipocytes differentiated in vitro. Ovarian failure induced by 4-vinylcyclohexene diepoxide treatment dramatically reduced BDNF and TH expression in gWAT, eliminated induction of UCP1 by CL, and reduced tissue metabolic rate.Conclusions
Collectively, these data demonstrate that female mice are more responsive than males to the recruitment of brown adipocytes in gonadal WAT and this difference corresponds to greater levels of estrogen-dependent sympathetic innervation.982.
Global analysis of phosphoproteome dynamics in embryonic development of zebrafish (Danio rerio) 总被引:1,自引:0,他引:1 下载免费PDF全文
Oh Kwang Kwon Sun Ju Kim You‐Mie Lee Young‐Hoon Lee Young‐Seuk Bae Jin Young Kim Xiaojun Peng Zhongyi Cheng Yingming Zhao Sangkyu Lee 《Proteomics》2016,16(1):136-149
The zebrafish (Danio rerio) is a popular animal model used for studies on vertebrate development and organogenesis. Recent research has shown a similarity of approximately 70% between the human and zebrafish genomes and about 84% of human disease‐causing genes have common ancestry with that of the zebrafish genes. Zebrafish embryos have a number of desirable features, including transparency, a large size, and rapid embryogenesis. Protein phosphorylation is a well‐known PTM, which can carry out various biological functions. Recent MS developments have enabled the study of global phosphorylation patterns by using MS‐based proteomics coupled with titanium dioxide phosphopeptide enrichment. In the present study, we identified 3500 nonredundant phosphorylation sites on 2166 phosphoproteins and quantified 1564 phosphoproteins in developing embryos of zebrafish. The distribution of Ser/Thr/Tyr phosphorylation sites in zebrafish embryos was found to be 88.9, 10.2, and 0.9%, respectively. A potential kinase motif was predicted using Motif‐X analysis, for 80% of the identified phosphorylation sites, with the proline‐directed motif appearing most frequently, and 35 phosphorylation sites having the pSF motif. In addition, we created six phosphoprotein clusters based on their dynamic pattern during the development of zebrafish embryos. Here, we report the largest dataset of phosphoproteins in zebrafish embryos and our results can be used for further studies on phosphorylation sites or phosphoprotein dynamics in zebrafish embryos. 相似文献
983.
984.
Jae-Yul Cha Sangjo Han Hee-Jeon Hong Hyunji Cho Daran Kim Youngho Kwon Soon-Kyeong Kwon Max Crüsemann Yong Bok Lee Jihyun F Kim Guri Giaever Corey Nislow Bradley S Moore Linda S Thomashow David M Weller Youn-Sig Kwak 《The ISME journal》2016,10(1):119-129
Crops lack genetic resistance to most necrotrophic pathogens. To compensate for this disadvantage, plants recruit antagonistic members of the soil microbiome to defend their roots against pathogens and other pests. The best examples of this microbially based defense of roots are observed in disease-suppressive soils in which suppressiveness is induced by continuously growing crops that are susceptible to a pathogen, but the molecular basis of most is poorly understood. Here we report the microbial characterization of a Korean soil with specific suppressiveness to Fusarium wilt of strawberry. In this soil, an attack on strawberry roots by Fusarium oxysporum results in a response by microbial defenders, of which members of the Actinobacteria appear to have a key role. We also identify Streptomyces genes responsible for the ribosomal synthesis of a novel heat-stable antifungal thiopeptide antibiotic inhibitory to F. oxysporum and the antibiotic''s mode of action against fungal cell wall biosynthesis. Both classical- and community-oriented approaches were required to dissect this suppressive soil from the field to the molecular level, and the results highlight the role of natural antibiotics as weapons in the microbial warfare in the rhizosphere that is integral to plant health, vigor and development. 相似文献
985.
Soon‐Hwan Kwon Ji‐Eun Bae Sang‐Hyup Lee Sang‐Dae Lee Kwon‐Seok Chae 《Entomological Research》2016,46(4):272-277
Geotaxis and phototaxis are movements in response to gravity and light, respectively, and are commonly observed in nature. The interactions between these two types of movement have been shown to confer ecological advantages to many taxa. Although several studies have been conducted on phototaxis and geotaxis in various organisms, reports on the interactions between positive phototaxis and negative geotaxis are lacking. In the fruit fly, Drosophila melanogaster, any direct interactions that exist between positive phototaxis and negative geotaxis are yet to be determined and the ecological significance of such interactions remains unclear. In the present study, the effects of gravity on positive phototaxis in a Y‐maze were investigated using the Canton‐S wild type and gravity‐sensing‐deficient pyx3 mutant fruit flies. Gravity sensing was not necessary for horizontal positive phototaxis, but was required for vertical positive phototaxis. These results suggest that gravitoreception may selectively modulate positive phototaxis depending on the vertical and horizontal movements of the fruit flies. 相似文献
986.
987.
988.
Jung Kwon Kim Seung Beom Ha Chan Hoo Jeon Jong Jin Oh Sung Yong Cho Seung-June Oh Hyeon Hoe Kim Chang Wook Jeong 《PloS one》2016,11(2)
Purpose
Shock-wave lithotripsy (SWL) is accepted as the first line treatment modality for uncomplicated upper urinary tract stones; however, validated prediction models with regards to stone-free rates (SFRs) are still needed. We aimed to develop nomograms predicting SFRs after the first and within the third session of SWL. Computed tomography (CT) information was also modeled for constructing nomograms.Materials and Methods
From March 2006 to December 2013, 3028 patients were treated with SWL for ureter and renal stones at our three tertiary institutions. Four cohorts were constructed: Total-development, Total-validation, CT-development, and CT-validation cohorts. The nomograms were developed using multivariate logistic regression models with selected significant variables in a univariate logistic regression model. A C-index was used to assess the discrimination accuracy of nomograms and calibration plots were used to analyze the consistency of prediction.Results
The SFR, after the first and within the third session, was 48.3% and 68.8%, respectively. Significant variables were sex, stone location, stone number, and maximal stone diameter in the Total-development cohort, and mean Hounsfield unit (HU) and grade of hydronephrosis (HN) were additional parameters in the CT-development cohort. The C-indices were 0.712 and 0.723 for after the first and within the third session of SWL in the Total-development cohort, and 0.755 and 0.756, in the CT-development cohort, respectively. The calibration plots showed good correspondences.Conclusions
We constructed and validated nomograms to predict SFR after SWL. To the best of our knowledge, these are the first graphical nomograms to be modeled with CT information. These may be useful for patient counseling and treatment decision-making. 相似文献989.
ELECTRON MICROSCOPY OF ABSORPTION OF TRACER MATERIALS BY TOAD URINARY BLADDER EPITHELIUM 总被引:3,自引:3,他引:0 下载免费PDF全文
Jae Kwon Choi 《The Journal of cell biology》1965,25(2):175-192
The absorption of Thorotrast and saccharated iron oxide by the epithelium of the toad urinary bladder was studied by electron microscopy. Whether the toads were hydrated, dehydrated, or given Pitressin, no significant differences in transport of colloidal particles by epithelial cells were observed. This implies that these physiological factors had little effect on the transport of the tracer particles. Tracer particles were encountered in three types of epithelial cells which line the bladder lumen, but most frequently in the mitochondria-rich cells. Tracer materials were incorporated into the cytoplasm of epithelial cells after being adsorbed to the coating layer covering the luminal surface of the cells. In the intermediate stage (1 to 3 hours after introducing tracer) particles were present in small vesicles, tubules, and multivesicular bodies. In the later stages (up to 65 hours), the particles were more commonly seen to be densely packed within large membrane-bounded bodies which were often found near the Golgi region. These large bodies probably were formed by the fusion of small vesicles. Irrespective of the stages of absorption, no particles were found in the intercellular spaces or in the submucosa. Particles apparently did not penetrate the intercellular spaces of the epithelium beyond the level of the tight junction. 相似文献
990.
We analyzed the DNA sequence of the 5' external transcribed spacer (ETS) and part of the intergenic transcribed spacer (IGS) of the aphid ribosomal RNA gene (rDNA). The 5' ETS of aphid rDNA consists of 843 nucleotides with a G/C content of 69 mol/100 mol, far higher than that of any other known 5' ETS for insect rDNA. The IGS of aphid rDNA contained a characteristic array of repeated sequences of 247 nucleotides. The repeated sequences were identical. It was shown that the number of the repeating sequence is heterogeneous. 相似文献