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91.
Initial functional studies have demonstrated that RNA‐binding motif protein 10 (RBM10) can promote apoptosis and suppress cell proliferation; however, the results of several studies suggest a tumour‐promoting role for RBM10. Herein, we assessed the involvement of RBM10 in lung adenocarcinoma cell proliferation and explored the potential molecular mechanism. We found that, both in vitro and in vivo, RBM10 overexpression suppresses lung adenocarcinoma cell proliferation, while its knockdown enhances cell proliferation. Using complementary DNA microarray analysis, we previously found that RBM10 overexpression induces significant down‐regulation of RAP1A expression. In this study, we have confirmed that RBM10 decreases the activation of RAP1 and found that EPAC stimulation and inhibition can abolish the effects of RBM10 knockdown and overexpression, respectively, and regulate cell growth. This effect of RBM10 on proliferation was independent of the MAPK/ERK and P38/MAPK signalling pathways. We found that RBM10 reduces the phosphorylation of CREB via the AKT signalling pathway, suggesting that RBM10 exhibits its effect on lung adenocarcinoma cell proliferation via the RAP1/AKT/CREB signalling pathway.  相似文献   
92.
Eukaryotes segregate chromosomes in "open" or "closed" mitosis, depending on whether their nuclear envelopes (NEs) break down or remain intact. Here we show that the control of the nuclear surface area may determine the choice between these two modes. The dividing nucleus does not expand its surface in the fission yeast Schizosaccharomyces japonicus, confining the mitotic spindle and causing it to?buckle. The NE ruptures in anaphase, releasing the compressive stress and allowing chromosome segregation.?Blocking the NE expansion in the related species Schizosaccharomyces pombe that undergoes closed mitosis induces spindle buckling and collapse in the absence of an intrinsic NE rupture mechanism. We propose that scaling considerations could have shaped the evolution of eukaryotic mitosis by necessitating either nuclear surface expansion or the NE breakdown.  相似文献   
93.
94.
A novel pink-coloured, non-spore-forming, non-motile, Gram-negative bacterium, designated YIM 48858T, is described by using a polyphasic approach. The strain can grow at pH 6.5–9 (optimum at pH 7) and 25–30°C (optimum at 28°C). NaCl is not required for its growth. Positive for oxidase and catalase. Urease activity, nitrate reduction, starch and Tween 80 tests are negative reaction. 16S rRNA gene sequence similarity studies showed that strain YIM 48858T is a member of the genus Rubellimicrobium, with similarities of 96.3, 95.7 and 95.5% to Rubellimicrobium mesophilum MSL-20T, Rubellimicrobium aerolatum 5715S-9T and Rubellimicrobium thermophilum DSM 16684T, respectively. Q-10 was the predominant respiratory ubiquinone as in the other members of the genus Rubellimicrobium. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphoglycolipid, glycolipid and the major fatty acids were C18:1 ω7c, C16:0 and C10:0 3-OH, which are very different from the valid published species. The DNA G + C content was 67.7 mol%. Both phylogenetic and chemotaxonomic evidence supports that YIM 48858T is a novel species of the genus Rubellimicrobium, for which the name Rubellimicrobium roseum sp. nov. is proposed. The type strain is YIM 48858T (=CCTCC AA 208029T =KCTC 23202T).  相似文献   
95.

Necroptosis is a programmed necrosis that is mediated by receptor-interacting protein kinases RIPK1, RIPK3 and the mixed lineage kinase domain-like protein, MLKL. Necroptosis must be strictly regulated to maintain normal tissue homeostasis, and dysregulation of necroptosis leads to the development of various inflammatory, infectious, and degenerative diseases. Ubiquitylation is a widespread post-translational modification that is essential for balancing numerous physiological processes. Over the past decade, considerable progress has been made in the understanding of the role of ubiquitylation in regulating necroptosis. Here, we will discuss the regulatory functions of ubiquitylation in necroptosis signaling pathway. An enhanced understanding of the ubiquitylation enzymes and regulatory proteins in necroptotic signaling pathway will be exploited for the development of new therapeutic strategies for necroptosis-related diseases.

  相似文献   
96.
Thylakoid formation1 protein (Thf1) is a multifunctional protein that is conserved in all photosynthetic organisms. In this study, we used the model cyanobacterium Synechococcus sp. PCC7942 (hereafter Synechococcus) to show that the level of Thf1 is altered in response to various stress conditions. Although this protein has been reported to be involved in thylakoid formation, the thylakoid membrane in the thf1 deletion strain (ΔThf1) was not affected. Compared with the WT, ΔThf1 showed reduced PS II activity, with increased levels of D1 under high light (HL) conditions, which was resulted from blocked D1 degradation by the FtsH protease and thus inhibits PS II repair. PS I was found to be more seriously affected than PS II in ΔThf1, even under low light conditions, suggesting that PS I damage could be the primary effect of thf1 deletion in Synechococcus. Further analysis revealed that the ΔThf1 mutant had a lower PS I subunit content and lower PS I stability under HL conditions. Further sucrose gradient fractionation of the membrane protein complexes and crosslinking and immunoblot analysis indicated that Thf1 interacts with PS I. Together, our results reveal that Thf1 interacts with PS I and thereby stabilizes PS I in Synechococcus.  相似文献   
97.
Spontaneous brain activity or off-line activity after memory encoding is associated with memory consolidation. A few recent resting-state functional magnetic resonance imaging (RS-fMRI) studies indicate that the RS-fMRI could map off-line memory consolidation effects. However, the gene effects on memory consolidation process remain largely unknown. Here we collected two RS-fMRI sessions, one before and another after an episodic memory encoding task, from two groups of healthy young adults, one with apolipoprotein E (APOE) ε2/ε3 and the other with APOE ε3/ε4. The ratio of regional homogeneity (ReHo), a measure of local synchronization of spontaneous RS-fMRI signal, of the two sessions was used as an index of memory-consolidation. APOE ε3/ε4 group showed greater ReHo ratio within the medial temporal lobe (MTL). The ReHo ratio in MTL was significantly correlated with the recognition memory performance in the APOE ε3/ε4 group but not in ε2/ε3 group. Additionally, APOE ε3/ε4 group showed lower ReHo ratio in the occipital and parietal picture-encoding areas. Our results indicate that APOE ε3/ε4 group may have a different off-line memory consolidation process compared to ε2/ε3 group. These results may help generate future hypotheses that the off-line memory consolidation might be impaired in Alzheimer’s disease.  相似文献   
98.
99.
用鲜花循环式动态顶空技术采集红厚壳鲜花的香气成分,TCT-GC-MS联用技术分析鉴定。4-羟基-2-丁酮,双烯酮,1、2-环氧-2-甲基丁烷,1、2-环氧-3-甲基丁烷,2-乙基戊烷,3-己醇,甲基环戊烷,2-丁醇等24个成分被检测出,占总离子流出峰面积的90.28%。并对结果进行了分析讨论。  相似文献   
100.
iQPR技术处理污水是一项新型尖端的技术,此技术可以成功降低污水乃至受到污染的地下水中的各种污染指标。但是,iQPR技术处理污水尤其是地下水是否存在潜在的生物安全性问题有待于进一步研究。因此,为评估iQPR技术对生物安全性的影响,本研究首先分析了三种不同iQPR法处理水的水质成分;其次系统研究了iQPR水对SD鼠在个体水平、组织水平和病理形态学损伤的研究。研究表明:iQPR处理的水质成分较对照组普通饮用水好,在个体组织水平检测未见异常,尽管其中一组iQPR处理水造成了SD鼠的脾小体增大,但是可能的原因是水处理环节存在微生物污染现象,因此,初步认定此技术未造成SD大鼠的个体损伤。本研究为揭示iQPR处理的水对生物体的安全性评价提供一个理论依据。  相似文献   
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