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21.
SeyyedReza SadatEbrahimi Hassan Amini Reza Rahbarghazi Paria Habibollahi Shahrouz Ghaderi Hadi Rajabi Aysa Rezabakhsh 《Journal of cellular and molecular medicine》2022,26(11):3120
Recently, cytokines belonging to C1q/tumour necrosis factor‐related proteins (CTRPs) superfamily have attracted increasing attention due to multiple metabolic functions and desirable anti‐inflammatory effects. These various molecular effectors exhibit key roles upon the onset of cardiovascular diseases, making them novel adipo/cardiokines. This review article aimed to highlight recent findings correlated with therapeutic effects and additional mechanisms specific to the CTRP9, particularly in cardiac ischaemia/reperfusion injury (IRI). Besides, the network of the CTPR9 signalling pathway and its possible relationship with IRI were discussed. Together, the discovery of all involved underlying mechanisms could shed light to alleviate the pathological sequelae after the occurrence of IRI. 相似文献
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Membranes of adjacent cells form intercellular junctional complexes to mechanically anchor neighbour cells (anchoring junctions), to seal the paracellular space and to prevent diffusion of integral proteins within the plasma membrane (tight junctions) and to allow cell-to-cell diffusion of small ions and molecules (gap junctions). These different types of specialised plasma membrane microdomains, sharing common adaptor molecules, particularly zonula occludens proteins, frequently present intermingled relationships where the different proteins co-assemble into macromolecular complexes and their expressions are co-ordinately regulated. Proteins forming gap junction channels (connexins, particularly) and proteins fulfilling cell attachment or forming tight junction strands mutually influence expression and functions of one another. 相似文献
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It has long been known (circa 1917) that environmental conditions, as well as speciation, can affect dramatically the frequency distribution of Spo11/Rec12-dependent meiotic recombination. Here, by analyzing DNA sequence-dependent meiotic recombination hotspots in the fission yeast Schizosaccharomyces pombe, we reveal a molecular basis for these phenomena. The impacts of changing environmental conditions (temperature, nutrients, and osmolarity) on local rates of recombination are mediated directly by DNA site-dependent hotspots (M26, CCAAT, and Oligo-C). This control is exerted through environmental condition-responsive signal transduction networks (involving Atf1, Pcr1, Php2, Php3, Php5, and Rst2). Strikingly, individual hotspots modulate rates of recombination over a very broad dynamic range in response to changing conditions. They can range from being quiescent to being highly proficient at promoting activity of the basal recombination machinery (Spo11/Rec12 complex). Moreover, each different class of hotspot functions as an independently controlled rheostat; a condition that increases the activity of one class can decrease the activity of another class. Together, the independent modulation of recombination rates by each different class of DNA site-dependent hotspots (of which there are many) provides a molecular mechanism for highly dynamic, large-scale changes in the global frequency distribution of meiotic recombination. Because hotspot-activating DNA sites discovered in fission yeast are conserved functionally in other species, this process can also explain the previously enigmatic, Prdm9-independent, evolutionarily rapid changes in hotspot usage between closely related species, subspecies, and isolated populations of the same species. 相似文献
26.
摘要 目的:分析锌指转录因子(Slug)、末端脱氧核糖核苷酸转移酶(TdT)、Y染色体性别决定区相关高速泳动族框因子9(SOX9)蛋白表达与胸腺瘤患者临床病理特征及预后的关系。方法:选择2016年5月至2018年11月在本院接受手术切除的113例胸腺瘤组织及癌旁组织,利用免疫组织化学法测定Slug、TdT、SOX9蛋白阳性表达,分析Slug、TdT、SOX9蛋白表达与胸腺瘤患者临床病理特征、预后的关系。结果:胸腺瘤组织Slug、TdT、SOX9蛋白阳性表达率均高于癌旁组织(P<0.05);胸腺瘤组织Slug、TdT、SOX9蛋白阳性表达在患者年龄、性别、肿瘤直径、是否合并重症肌无力、是否伴有大血管侵犯方面比较,差异无统计学意义(P>0.05);胸腺瘤组织Slug、TdT、SOX9蛋白阳性表达在Masaoka-Koga分期、WHO分型方面比较,差异有统计学意义(P<0.05);胸腺瘤组织Slug、TdT、SOX9蛋白阳性表达与Masaoka-Koga分期、WHO分型呈正相关(P<0.05);113例胸腺瘤患者随访5年总生存率为81.42%(92/113),Slug阳性组5年生存率低于Slug阴性组(70.18% VS 92.86%),TdT阳性组5年生存率低于TdT阴性组(79.790% VS 89.57%),SOX9阳性组5年生存率低于SOX9阴性组(79.35% VS 90.48%)(χ2=9.669、9.515、17.008,P<0.05);Cox比例风险回归模型分析发现,Masaoka-Koga分期(Ⅲ期/Ⅳ期)、WHO分型(B2/B3)、Slug蛋白阳性表达、TdT蛋白阳性表达、SOX9蛋白阳性表达是影响胸腺瘤患者预后的独立危险因素(HR:3.518、2.921、4.536、1.402、2.921,P<0.05)。结论:胸腺瘤组织Slug、TdT、SOX9呈高表达,三者蛋白表达与患者Masaoka-Koga分期、WHO分型有关,且是影响胸腺瘤患者5年生存率的独立危险因素。 相似文献
27.
Yafei Tian Yongping Zhang Shaoyan Hu Lilan Yao Yijian Zhu Shenglong Qiao Daru Lu Junjie Fan 《Blood and Genomics》2021,664(1):63-67
MYH9-related diseases (MYH9-RD) are a group of autosomal dominant diseases caused by mutations in the MYH9 gene, which are featured by thrombocytopenia, giant platelets and granulocyte cytoplasmic inclusion bodies. MYH9-RD patients generally suffer from bleeding syndromes, progressive kidney disease, deafness, or cataracts. Here, we reported on a case of MYH9-RD. A novel heterozygous mutation of MYH9 (c.2344-2345delGTinsTA, p.T782Y) was discovered by targeted sequencing technology. Immunofluorescence analysis of neutrophils confirmed abnormal aggregation of MYH9 protein. The results of this study should expand the MYH9 gene mutation spectrum and provide reference for subsequent researchers and genetic counseling. 相似文献
28.
摘要 目的:构建Luc+CD38-的Raji细胞株,并进行功能的初步验证,为后期探索淋巴瘤细胞CD38位点免疫逃逸现象奠定基础。方法:通过CRISPR-cas9技术和PiggyBac(PB)转座子系统,对Luc+Raji细胞的CD38基因位点进行敲除,构建Luc+CD38-Raji细胞株,使用流式细胞术检测与Luc+CD38-Raji细胞株以1:1的比例共孵育CD19 CAR-T和CD38 CAR-T以及未转导的原始T细胞表面活化因子CD69的表达水平,荧光素酶检测法检测上述几组效应细胞对Luc+CD38-Raji细胞株的杀伤效率。结果:成功构建Luc+CD38-Raji细胞,激活实验结果显示,CD19 CAR-T与CD38 CAR-T均可以被Luc+Raji细胞激活。而Luc+CD38-Raji19号单克隆细胞由于缺失CD38的表达,仅能够激活CD19 CAR-T。杀伤实验结果显示,两种CAR-T细胞均能够对Luc+Raji细胞进行杀伤,而CD38 CAR-T对Luc+CD38-Raji19号单克隆细胞的杀伤效率与原始的T细胞相似。结论:成功构建了Luc+CD38-Raji细胞株,为后期探索淋巴瘤CD38位点免疫逃逸现象奠定基础。 相似文献
29.
Mosses have substantial amounts of long chain C20 polyunsaturated fatty acids, such as arachidonic and eicosapentaenoic acid, in addition to the shorter chain C18 α-linolenic and linoleic acids, which are typical substrates of lipoxygenases in flowering plants. To identify the fatty acid substrates used by moss lipoxygenases, eight lipoxygenase genes from Physcomitrella patens were heterologously expressed in Escherichia coli, and then analyzed for lipoxygenase activity using linoleic, α-linolenic and arachidonic acids as substrates. Among the eight moss lipoxygenases, only seven were found to be enzymatically active in vitro, two of which selectively used arachidonic acid as the substrate, while the other five preferred α-linolenic acid. Based on enzyme assays using a Clark-type oxygen electrode, all of the active lipoxygenases had an optimum pH at 7.0, except for one with highest activity at pH 5.0. HPLC analyses indicated that the two arachidonic acid lipoxygenases form (12S)-hydroperoxy eicosatetraenoic acid as the main product, while the other five lipoxygenases produce mainly (13S)-hydroperoxy octadecatrienoic acid from α-linolenic acid. These results suggest that mosses may have both C20 and C18 based oxylipin pathways. 相似文献
30.
Rogelio Zamilpa Elizabeth F. Lopez Ying Ann Chiao Qiuxia Dai Gladys P. Escobar Kevin Hakala Susan T. Weintraub Merry L. Lindsey 《Proteomics》2010,10(11):2214-2223
Matrix metalloproteinase‐9 (MMP‐9) deletion has been shown to improve remodeling of the left ventricle post‐myocardial infarction (MI), but the mechanisms to explain this improvement have not been fully elucidated. MMP‐9 has a broad range of in vitro substrates, but relevant in vivo substrates are incompletely defined. Accordingly, we evaluated the infarct regions of wild‐type (wt) and MMP‐9 null (null) mice using a proteomic strategy. Wt and null groups showed similar infarct sizes (48±3 in wt and 45±3% in null), indicating that both groups received an equal injury stimulus. Left ventricle infarct tissue was homogenized and analyzed by 2‐DE and MS. Of 31 spot intensity differences, the intensities of 9 spots were higher and 22 spots were lower in null mice compared to wt (all p<0.05). Several extracellular matrix proteins were identified in these spots by MS, including fibronectin, tenascin‐C, thrombospondin‐1, and laminin. Fibronectin was observed on the gels at a lower than expected molecular weight in the wt group, which suggested substrate cleavage, and the lower molecular weight spot was observed at lower intensity in the MMP‐9 null group, which suggested cleavage by MMP‐9. Immunoblotting confirmed the presence of fibronectin cleavage products in the wt samples and lower levels in the absence of MMP‐9. In conclusion, examining infarct tissue from wt and MMP‐9 null mice by proteomic analysis provides a powerful and unique method to identify in vivo candidate MMP substrates. 相似文献