全文获取类型
收费全文 | 1623篇 |
免费 | 109篇 |
国内免费 | 5篇 |
出版年
2023年 | 13篇 |
2022年 | 22篇 |
2021年 | 61篇 |
2020年 | 30篇 |
2019年 | 37篇 |
2018年 | 33篇 |
2017年 | 24篇 |
2016年 | 51篇 |
2015年 | 107篇 |
2014年 | 92篇 |
2013年 | 99篇 |
2012年 | 126篇 |
2011年 | 121篇 |
2010年 | 82篇 |
2009年 | 75篇 |
2008年 | 90篇 |
2007年 | 91篇 |
2006年 | 74篇 |
2005年 | 61篇 |
2004年 | 64篇 |
2003年 | 56篇 |
2002年 | 43篇 |
2001年 | 18篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 15篇 |
1997年 | 13篇 |
1996年 | 14篇 |
1995年 | 12篇 |
1994年 | 5篇 |
1993年 | 12篇 |
1992年 | 7篇 |
1991年 | 13篇 |
1990年 | 11篇 |
1989年 | 5篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 7篇 |
1985年 | 10篇 |
1984年 | 9篇 |
1983年 | 10篇 |
1982年 | 8篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1975年 | 4篇 |
1971年 | 4篇 |
1954年 | 4篇 |
排序方式: 共有1737条查询结果,搜索用时 140 毫秒
91.
Xi-Hua Liu Lian-Wen Qi Raphael N. Alolga Qun Liu 《International journal of biological sciences》2022,18(1):292
Fibrinogen-like protein 1 (FGL1) is a novel hepatokine that forms part of the fibrinogen superfamily. It is predominantly expressed in the liver under normal physiological conditions. When the liver is injured by external factors, such as chemical drugs and radiation, FGL1 acts as a protective factor to promote the growth of regenerated cells. However, elevated hepatic FGL1 under high fat conditions can cause lipid accumulation and inflammation, which in turn trigger the development of non-alcoholic fatty liver disease, diabetes, and obesity. FGL1 is also involved in the regulation of insulin resistance in adipose tissues and skeletal muscles as a means of communication between the liver and other tissues. In addition, the abnormally changed FGL1 levels in the plasma of cancer patients make it a potential predictor of cancer incidence in clinical practice. FGL1 was recently identified as a major functional ligand of the immune inhibitory receptor, lymphocyte-activation gene 3 (LAG3), thus making it a promising target for cancer immunotherapy except for the classical programmed cell death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) axis. Despite the potential of FGL1 as a new cancer biomarker and therapeutic target, there are few related studies and much of what has been reported are superficial and lack depth and particularity. Therefore, elucidating the role and underlying mechanisms of FGL1 could be crucial for the development of promising diagnostic and therapeutic strategies for related diseases. Here, we provide a comprehensive review of the cellular mechanisms and clinical prospects of FGL1 in the prevention and treatment of liver diseases, metabolic disorders and cancer, and proffer suggestions for future studies. 相似文献
92.
Spermatogenesis is inhibited in Balb/C mice as a result of oxyradical insult. However, mammalian spermatocytes and synaptonemal complexes retain their structure and function after oxyradical insult due to protection afforded by the antioxidant vitamin E. Control groups were compared with experimental groups which were fed various vitamin E-deficient diets and subjected to varying times in an humidified 100% oxygen (hyperoxia) chamber. Measurements were made of sex body volume (SBV), nuclear envelope aberrations (NEA), and synaptonemal complex structure in spermatocytes during pachytene of meiosis prophase I. Changes in the volume of the sex body were positively correlated with increased oxyradical insult. The structure of the synaptonemal complex was not altered in any of the experimental groups which is a significant observation. It is suggested that vitamin E affords antioxidant protection and inhibits the alteration of membranes and sex chromosomes in mice during meiosis. 相似文献
93.
Urvater JA Hickman H Dzuris JL Prilliman K Allen TM Schwartz KJ Lorentzen D Shufflebotham C Collins EJ Neiffer DL Raphael B Hildebrand W Sette A Watkins DI 《Journal of immunology (Baltimore, Md. : 1950)》2001,166(5):3334-3344
The human MHC class I gene, HLA-B27, is a strong risk factor for susceptibility to a group of disorders termed spondyloarthropathies (SpAs). HLA-B27-transgenic rodents develop SpAs, implicating HLA-B27 in the etiology of these disorders. Several nonhuman primates, including gorillas, develop signs of SpAs indistinguishable from clinical signs of humans with SpAs. To determine whether SpAs in gorillas have a similar HLA-B27-related etiology, we analyzed the MHC class I molecules expressed in four affected gorillas. Gogo-B01, isolated from three of the animals, has only limited similarity to HLA-B27 at the end of the alpha1 domain. It differs by several residues in the B pocket, including differences at positions 45 and 67. However, the molecular model of Gogo-B*0101 is consistent with a requirement for positively charged residues at the second amino acid of peptides bound by the MHC class I molecule. Indeed, the peptide binding motif and sequence of individual ligands eluted from Gogo-B*0101 demonstrate that, like HLA-B27, this gorilla MHC class I molecule binds peptides with arginine at the second amino acid position of peptides bound by the MHC class I molecule. Furthermore, live cell binding assays show that Gogo-B*0101 can bind HLA-B27 ligands. Therefore, although most gorillas that develop SpAs express an MHC class I molecule with striking differences to HLA-B27, this molecule binds peptides similar to those bound by HLA-B27. 相似文献
94.
Twist, a master regulator of morphogenesis, plays an essential role in tumor metastasis 总被引:107,自引:0,他引:107
Yang J Mani SA Donaher JL Ramaswamy S Itzykson RA Come C Savagner P Gitelman I Richardson A Weinberg RA 《Cell》2004,117(7):927-939
95.
da Silva AJ Coelho AL Simas AB Moraes RA Pinheiro DA Fernandes FF Arruda EZ Costa PR Melo PA 《Bioorganic & medicinal chemistry letters》2004,14(2):431-435
Edunol (3), a pterocarpan isolated from Harpalyce brasiliana, a plant used in the northeast of Brazil against snakebites, was obtained by synthesis and showed antimyotoxic, antiproteolytic and PLA2 inhibitor properties. These proprieties could be improved through the synthesis of a bioisoster (5), where the prenyl group was replaced by the benzyl group. 相似文献
96.
J?Craig CohenEmail author Lennart?KA?Lundblad Jason?HT?Bates Michael?Levitzky Janet?E?Larson 《BMC genetics》2004,5(1):21
Background
Cystic Fibrosis is a pleiotropic disease in humans with primary morbidity and mortality associated with a lung disease phenotype. However, knockout in the mouse of cftr, the gene whose mutant alleles are responsible for cystic fibrosis, has previously failed to produce a readily, quantifiable lung phenotype. 相似文献97.
98.
Backbone dynamics of the human MIA protein studied by (15)N NMR relaxation: implications for extended interactions of SH3 domains 总被引:1,自引:0,他引:1 下载免费PDF全文
Stoll R Renner C Buettner R Voelter W Bosserhoff AK Holak TA 《Protein science : a publication of the Protein Society》2003,12(3):510-519
The melanoma inhibitory activity (MIA) protein is a clinically valuable marker in patients with malignant melanoma as enhanced values diagnose metastatic melanoma stages III and IV. Here, we report the backbone dynamics of human MIA studied by (15)N NMR relaxation experiments. The folded core of human MIA is found to be rigid, but several loops connecting beta-sheets, such as the RT-loop for example, display increased mobility on picosecond to nanosecond time scales. One of the most important dynamic features is the pronounced flexibility of the distal loop, comprising residues Asp 68 to Ala 75, where motions on time scales up to milliseconds occur. Further, significant exchange contributions are observed for residues of the canonical binding site of SH3 domains including the RT-loop, the n-Src loop, for the loop comprising residues 13 to 19, which we refer to as the"disulfide loop", in part for the distal loop, and the carboxyl terminus of human MIA. The functional importance of this dynamic behavior is discussed with respect to the biological activity of several point mutations of human MIA. The results of this study suggest that the MIA protein and the recently identified highly homologous fibrocyte-derived protein (FDP)/MIA-like (MIAL) constitute a new family of secreted proteins that adopt an SH3 domain-like fold in solution with expanded ligand interactions. 相似文献
99.
Izbicki G Breuer R 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(6):2767-8; author reply 2768
100.
Falk R 《Journal of the history of biology》2003,36(1):87-117
Genetics was established on a strictparticulate conception of heredity. Geneticlinkage, the deviation from independentsegregation of Mendelian factors, was conceivedas a function of the material allocation of thefactors to the chromosomes, rather than to themultiple effects (pleiotropy) of discretefactors. Although linkage maps wereabstractions they provided strong support forthe chromosomal theory of inheritance. DirectCytogenetic evidence was scarce until X-rayinduced major chromosomal rearrangementsallowed direct correlation of genetic andcytological rearrangements. Only with thediscovery of the polytenic giant chromosomes inDrosophila larvae in the 1930s were thevirtual maps backed up by physical maps of thegenetic loci. Genetic linkage became a pivotalexperimental tool for the examination of theintegration of genetic functions in developmentand in evolution. Genetic mapping has remaineda hallmark of genetic analysis. The location ofgenes in DNA is a modern extension of thenotion of genetic linkage. 相似文献