全文获取类型
收费全文 | 58630篇 |
免费 | 5117篇 |
国内免费 | 4973篇 |
专业分类
68720篇 |
出版年
2024年 | 114篇 |
2023年 | 756篇 |
2022年 | 1645篇 |
2021年 | 2737篇 |
2020年 | 1818篇 |
2019年 | 2287篇 |
2018年 | 2131篇 |
2017年 | 1693篇 |
2016年 | 2386篇 |
2015年 | 3501篇 |
2014年 | 4098篇 |
2013年 | 4395篇 |
2012年 | 5233篇 |
2011年 | 4867篇 |
2010年 | 2921篇 |
2009年 | 2708篇 |
2008年 | 3140篇 |
2007年 | 2804篇 |
2006年 | 2444篇 |
2005年 | 2175篇 |
2004年 | 1888篇 |
2003年 | 1667篇 |
2002年 | 1464篇 |
2001年 | 1236篇 |
2000年 | 1030篇 |
1999年 | 963篇 |
1998年 | 599篇 |
1997年 | 596篇 |
1996年 | 540篇 |
1995年 | 448篇 |
1994年 | 454篇 |
1993年 | 344篇 |
1992年 | 506篇 |
1991年 | 438篇 |
1990年 | 392篇 |
1989年 | 285篇 |
1988年 | 267篇 |
1987年 | 220篇 |
1986年 | 176篇 |
1985年 | 208篇 |
1984年 | 139篇 |
1983年 | 128篇 |
1982年 | 95篇 |
1981年 | 75篇 |
1980年 | 65篇 |
1979年 | 94篇 |
1978年 | 78篇 |
1977年 | 59篇 |
1976年 | 61篇 |
1973年 | 59篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
The purpose of this review is to provide an overview of the effects of adenovirus and influenza virus infections on obesity in various experimental models. We reviewed studies that were conducted within the past 10 years and were related to virus infection and obesity prevalence. Here, we discuss a different causal relationship between adenovirus and influenza infections with obesity. Adenovirus infection can cause obesity, whereas obesity can be a risk factor for increasing influenza virus infection and increases the risk of morbidity and mortality. The prevalence of obesity due to adenovirus infections may be due to an increase in glucose uptake and reduction in lipolysis caused by an increase in corticosterone secretion. Adenovirus infections may lead to increases in appetite by decreasing norepinephrine and leptin levels and also cause immune dysfunction. The relationship between obesity and influenza virus infection could be summarized by the following features: decreases in memory T-cell functionality and interferon (IFN)-α, IFN-β, and IFN-γ mRNA expression, increases in viral titer and infiltration, and impaired dendritic cell function in obese individuals. Moreover, leptin resistance may play an important role in increasing influenza virus infections in obese individuals. In conclusion, prevention of adenovirus infections could be a good approach for reducing obesity prevalence, and prevention of obesity could reduce influenza virus infections from the point of view of viral infections and obesity. 相似文献
64.
65.
Yuhui He Makusu Tsutsui Ralph H. Scheicher Chun Fan Masateru Taniguchi Tomoji Kawai 《Biophysical journal》2013
Experiments using nanopores demonstrated that a salt gradient enhances the capture rate of DNA and reduces its translocation speed. These two effects can help to enable electrical DNA sequencing with nanopores. Here, we provide a quantitative theoretical evaluation that shows the positive net charges, which accumulate around the pore entrance due to the salt gradient, are responsible for the two observed effects: they reinforce the electric capture field, resulting in promoted molecule capture rate; and they induce cationic electroosmotic flow through the nanopore, thus significantly retarding the motion of the anionic DNA through the nanopore. Our multiphysical simulation results show that, during the polymer trapping stage, the former effect plays the major role, thus resulting in promoted DNA capture rate, while during the nanopore-penetrating stage the latter effect dominates and consequently reduces the DNA translocation speed significantly. Quantitative agreement with experimental results has been reached by further taking nanopore wall surface charges into account. 相似文献
66.
67.
68.
X. Y. Li C. M. Han Y. Wang H. Z. Liu Z. F. Wu Q. H. Gao S. H. Zhao 《Animal genetics》2010,41(5):537-540
RIG-1 signalling is responsible for the detection of cytoplasmic viral RNA molecules. DEXH (Asp-Glu-X-His) box polypeptide 58 (encoded by DHX58) is a negative regulator of the RIG-1 signalling pathway. In human, the DHX58 gene can be upregulated and can inhibit the RIG-1 signalling pathway during viral infection. In this study, porcine DHX58 gene expression patterns were studied. According to our results, the porcine DHX58 gene was upregulated not only by the stimulation of Poly I:C but also by the stimulation of 1ipopolysaccharides (LPS). One polymorphism (g.4919G>C), detected in the ninth intron, was significantly associated with some blood parameters including the red cell distribution width of 1-day-old pigs and white blood cell counts, lymphocyte absolute counts, and platelet distribution width of 17-day-old pigs (P < 0.05). Moreover, the individuals with the genotype GG have a significantly higher mean white blood cell count than individuals with genotype CC or GC (P < 0.05). Our study indicates that DHX58 is an important gene that is associated with the immune response in swine. 相似文献
69.
70.
Inhibitors of ADP-ribosylation inhibited the myeloid differentiation of murine myelomonocytic leukemia, WEHI-3BD+ cells induced by granulocyte colony-stimulating factor. Benzamide, at 2.0 mM, inhibited 50% of the WEHI-3BD+ cell differentiation but had no significant effect on the proliferation. However, benzylaminododecylguanine hydrochloride and p-methoxylbenzylaminodecamethylene guanidine sulfate at 2.0 and 2.2 microM, respectively, inhibited 50% of proliferation but had no effect at all on differentiation. The differential effects of inhibitors provide a model to study the role of ADP-ribosylation in myeloid differentiation. 相似文献