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新疆乌鲁木齐HIV—1流行毒株膜蛋白基因C2—V3区序列测定和亚型分析 总被引:10,自引:0,他引:10
应用PCR方法对7份1996年3-5月采集于新疆乌鲁木齐HIV-1阳性静脉吸毒者的外周血单核细胞样品进行扩增,获得了HIV-1膜蛋白基因的核酸片段,并对其C2-V3区及邻区350-450个核苷酸序列进行了测定和分析。 相似文献
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TGF-β超家族在软骨发生、发育和维持中的作用 总被引:1,自引:0,他引:1
转化生长因子b(Transforming growth factor b, TGF-b)超家族包括TGF-b和骨形态发生蛋白(Bone morphogenetic protein,BMP)两个亚家族。TGF-b超家族信号通路的配体、配体拮抗分子、受体、信号转导分子均在软骨内成骨过程中发挥各自独特的作用, 参与调控软骨细胞的谱系分化、增殖、成熟、凋亡和矿化。BMP信号能起始间充质细胞向软骨细胞分化并维持软骨细胞的特性, 在软骨发生过程中起主导作用; 在生长板发育的过程中, BMP信号促进软骨细胞的成熟, 促进成骨, 而TGF-b信号抑制软骨细胞的肥大分化, 维持生长板中适量的软骨细胞; TGF-b信号和BMP信号对于关节软骨的维持和修复都是不可或缺的。因此, TGF-b超家族的重要作用贯穿骨骼发育过程的始终。 相似文献
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Yuan Xie KaiWei Fan ShiXing Guan Yang Hu Yi Gao WeiJie Zhou 《Journal of cellular and molecular medicine》2022,26(13):3598
LECT2 (leucocyte cell‐derived chemotaxin 2) is a 16‐kDa protein mainly produced by hepatocytes. It was first isolated in PHA‐activated human T‐cell leukaemia SKW‐3 cells and originally identified as a novel neutrophil chemotactic factor. However, many lines of studies suggested that LECT2 was a pleiotropic protein, it not only functioned as a cytokine to exhibit chemotactic property, but also played multifunctional roles in some physiological conditions and pathological abnormalities, involving liver regeneration, neuronal development, HSC(haematopoietic stem cells) homeostasis, liver injury, liver fibrosis, hepatocellular carcinoma, metabolic disorders, inflammatory arthritides, systemic sepsis and systemic amyloidosis. Among the above studies, it was discovered that LECT2 could be a promising molecular biomarker and therapeutic target. This review summarizes LECT2‐related receptors and pathways, basic and clinical researches, primarily in mice and human, for a better comprehension and management of these diseases in the future. 相似文献
87.
Tong-Wei Guan Hui-Ping Zhao Zhen-Ming Che Xiao-Ping Zhang Li-Li Zhang 《Antonie van Leeuwenhoek》2013,104(5):787-792
A novel halophilic, filamentous actinomycete, designated TRM 4064T, was isolated from a hypersaline habitat in Sichuan Province, China. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of strain TRM 4064T showed that it was most closely related to Actinopolyspora mortivallis (99.1 % sequence similarity). The sequence similarities between strain TRM 4064T and other Actinopolyspora species with validly-published names were <97.0 %. However, it had relatively low mean values for DNA–DNA relatedness with the A. mortivallis DSM 44261T (23.2 %). Optimal growth occurred at 37 °C, pH 7.0 and in the presence of 13 % (w/v) NaCl. The whole-cell sugar pattern consists of xylose, glucose, ribose and arabinose. The predominant menaquinones are MK-10(H4) (38.2 %), MK-9(H4) (25.1 %), MK-9(H2) (28.6 %) and MK-8(H4) (7.3 %). The major fatty acids are anteiso-C17:0 (36.9 %) and iso-C17:0 (19.3 %). The diagnostic phospholipids detected were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylinositol (PI) and two unknown phospholipids. The G+C content of the genomic DNA of the type strain is 66.3 mol%. Strain TRM 4064T therefore represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora dayingensis sp. nov. is proposed. The type strain is TRM 4064T (= KCTC 19979T = CCTCC AA 2010010T). 相似文献
88.
Objectives: Many kinds of cardiac progenitor cell populations have been identified, including c‐kit+, Nkx2.5+s and GATA4+ cells. However, these progenitors have limited ability to differentiate into different cardiac cell types. Recently, a new kind of cardiac progenitor cell named the multipotent Isl1+ cardiovascular progenitor (MICPs) has been identified, which also expresses Nkx2.5, GATA4, CD34 and Flk1. Materials and methods: In this study, we have isolated and characterized MICPs from chicken embryonic heart tissues using immunofluorescence and PCR. Results: Results shown that they express markers of cardiac progenitor cells, with high clonality. They have the ability to self‐renew and can give rise to three types of heart cell in vitro. Conclusions: Myocytes, smooth muscle cells and endothelial cells. Our work provides evidence for a developmental paradigm of the heart, that endothelial and muscle lineage diversification arises from multipotent cardiac progenitor cells. Existence of these cells provides a new opportunity for myocardial injury repair. 相似文献
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