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101.
102.
In hypoxic cells, dysfunctional mitochondria are selectively removed by a specialized autophagic process called mitophagy. The ER–mitochondrial contact site (MAM) is essential for fission of mitochondria prior to engulfment, and the outer mitochondrial membrane protein FUNDC1 interacts with LC3 to recruit autophagosomes, but the mechanisms integrating these processes are poorly understood. Here, we describe a new pathway mediating mitochondrial fission and subsequent mitophagy under hypoxic conditions. FUNDC1 accumulates at the MAM by associating with the ER membrane protein calnexin. As mitophagy proceeds, FUNDC1/calnexin association attenuates and the exposed cytosolic loop of FUNDC1 interacts with DRP1 instead. DRP1 is thereby recruited to the MAM, and mitochondrial fission then occurs. Knockdown of FUNDC1, DRP1, or calnexin prevents fission and mitophagy under hypoxic conditions. Thus, FUNDC1 integrates mitochondrial fission and mitophagy at the interface of the MAM by working in concert with DRP1 and calnexin under hypoxic conditions in mammalian cells.  相似文献   
103.
SDA1 encodes a highly conserved protein that is widely distributed in eukaryotic organisms. SDA1 is essential for cell cycle progression and organization of the actin cytoskeleton in yeasts and humans. In this study, we identified a Phytophthora capsici orthologue of yeast SDA1, named PcSDA1. In P. capsici, PcSDA1 is strongly expressed in three asexual developmental states (mycelium, sporangia and germinating cysts), as well as late in infection. Silencing or overexpression of PcSDA1 in P. capsici transformants affected the growth of hyphae and sporangiophores, sporangial development, cyst germination and zoospore release. Phalloidin staining confirmed that PcSDA1 is required for organization of the actin cytoskeleton. Moreover, 4′,6‐diamidino‐2‐phenylindole (DAPI) staining and PcSDA1‐green fluorescent protein (GFP) fusions revealed that PcSDA1 is involved in the regulation of nuclear distribution in hyphae and sporangia. Both silenced and overexpression transformants showed severely diminished virulence. Thus, our results suggest that PcSDA1 plays a similar role in the regulation of the actin cytoskeleton and nuclear division in this filamentous organism as in non‐filamentous yeasts and human cells.  相似文献   
104.
105.
Shi X  Wang C  Zhuang Z  Lu J  Liu J  Wu J  Cao R  Li T 《Regulatory peptides》2011,170(1-3):52-56
Synthetic human parathyroid (1-34) (hPTH (1-34)) is known to have the full biological activity of the holohormone for osteoporosis. This study is about designing a novel analog of hPTH (1-34) which is more suitable for intranasal administration. We likewise evaluate effectiveness of the nasal drops against osteoroporosis. Through fusion expression of combining gene, cell disruption, inclusion body washing, ethanol fraction precipitation, acid hydrolysis, and CM-52 ion exchange column chromatography Pro-Pro-[Arg11] hPTH (1-34)-Pro-Pro was designed and produced. Nasal drops of Pro-Pro-[Arg11] hPTH (1-34)-Pro-Pro were prepared and administrated to ovariectomized rats. After 12 weeks of raising, Bone Material Densities (BMD) of vertebrae were examined by Dual Energy X-Ray Absorptiometry (DEXA). The average BMD of these groups treated with nasal drops of the peptide were 28.0%-47.2% (P<0.01) higher than that of the group treated with normal saline (NS). The subchondral bone plates of the femoral heads were examined by scanning electron microscopy and a defined planar section was photographed. Percentage of the area of the cancellous bone was calculated. Percentages of the groups treated with nasal drops of the peptide increased; values were significantly different to that of the group treated with NS (P<0.001) and were even equivalent to that of normal groups. These results show that nasal drops of Pro-Pro-[Arg11] hPTH (1-34)-Pro-Pro are effective against osteoporosis.  相似文献   
106.
A new fungicolous species, Cosmospora inonoticola, is described and illustrated based on a specimen collected from northeast China. It is characterized by the occurrence of fruitbodies of Inonotus sp.; perithecia nonstromatic, subglobose to pyriform, not collapsing when dry; clavate asci containing (3–)6(?8) spores; ascospores ellipsoidal to broadly ellipsoidal, pale brown, finely warted, bicellular, conspicuously constricted at septum; and producing a verticillium-like asexual state. A multi-locus analysis of the combined ITS, rpb1 and tub sequences confirmed its taxonomic position, and revealed the distinction from its morphologically similar species including the type species, C. coccinea, which occurs also on Inonotus. A specimen with sexual state of C. lavitskiae is reported for the first time, and a reference specimen is indicated.  相似文献   
107.
Single-molecule folding   总被引:6,自引:0,他引:6  
Recent developments in fluorescence and force spectroscopy enable us to go beyond the ensemble average and measure the behavior of individual biomacromolecules. These single-molecule approaches can directly resolve transient intermediate states and multiple reaction pathways, and thus are uniquely powerful in characterizing the complex dynamics of biological processes. Recent applications of these two techniques to the protein and RNA folding problems have led to exciting new results.  相似文献   
108.
重组干扰素γ的中间试制   总被引:6,自引:0,他引:6  
童蔡塘  宋一鸣 《病毒学报》1997,13(2):134-139
用带有表达质粒PBV220(含有γ干扰素基因)的大肠杆菌DH5α株进行发酵培养,3批中试的菌产量平均为14.1克/L,γ干扰素的表达量平均为1.02±10^9IU/L,收集的菌体经高压匀质破菌后收集包涵体,用7mol/L盐酸胍提取干扰素,此过程中去除78.4%菌体蛋白,而干扰素活性仅损失10.41%,粗制干扰素经复性可使干扰素活性提高405%,比活也有明显提高,3批平均为1.76×10^7IU/m  相似文献   
109.
陈庄  杜勇 《Virologica Sinica》1997,12(4):329-335
用RT-PCR法从一名抗-HCV阳性献血员血清中扩增到约900bp的DNA片段,经EcoRI酶切后插入pET17Xb表达质粒。SDS-PAGE表明重组质粒在约65kD处有融合蛋白表达,表达蛋白含量约为24%。对其插入片段进行序列分析:核着酸长度为945bp,A:T:G:C比例为18.6:21.9:30.5:29.0,G/C含量占59%,与其它一些HCV殊比较,核着酸同源性Ⅰ型为77.1%.Ⅲ、Ⅳ、Ⅴ、Ⅵ型均<70%.Ⅱ型各株均>90%;氨基酸序列比较的同源性Ⅰ型为857%,Ⅲ、Ⅳ、ⅤⅥ型各株均>70%,Ⅱ型各株均>93%。NS4基因的克隆和表达为其基因和产物作用的进一步研究奠定了基础。  相似文献   
110.
水稻染色体标本制备的风油精法   总被引:2,自引:0,他引:2  
水稻的染色体较小,不同的染色体在形态上较难区分。常规的压片技术由于很难使染色体分散,且也不能完全排除细胞质的干扰,因而很不适用于水稻染色体核型分析及显带。Kurata 等(1978)采用酶解与火焰干燥技术制备水稻染色体标本,获得清晰的染色体图象,从而成功地进行了水稻染色体的核型分析。陈瑞阳等(1982)参照人类染色体  相似文献   
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