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1.
目的:探讨STZ诱导糖尿病大鼠ghrelin和nesfatin-1动力学及分泌调节变化。方法:STZ诱导糖尿病大鼠模型;采用葡糖糖脱氢酶分析法测量血浆葡萄糖水平;免疫放射分析检测血浆ghrelin、nesfatin-1、胰岛素、胰岛素样生长因子1(IGF-1)、生长激素(GH)含量;采用real-time PCR检测ghrelin m RNA水平变化;免疫组化观察ghrelin和nesfatin-1免疫活性细胞数量。结果:糖尿病大鼠体重显著降低(t=23.16,P<0.01),血糖水平显著升高(t=22.55,P<0.01),血浆胰岛素和IGF-1水平显著降低(t=6.50,t=24.13,P<0.01),但GH水平显著升高(t=3.30,P<0.05)。糖尿病大鼠血浆总ghrelin(t=7.03,P<0.01)和活性ghrelin(t=3.33,P<0.05)水平均显著升高,血浆nesfatin-1水平则显著降低(t=6.24,P<0.01);糖尿病大鼠血浆总ghrelin与GH(r=0.81,P<0.01)和IGF-1水平(r=-0.58,P<0.01)呈显著相关性;与对照组大鼠相比,糖尿病大鼠胃总ghrelin(t=16.86,P<0.01)和活性ghrelin(t=3.30,P<0.05)水平均显著降低;而胃nesfatin-1(t=7.93,P<0.01)水平则显著升高。胃总ghrelin水平与血浆IGF-1水平呈明显相关性(r=0.65,P<0.01);与对照组大鼠相比,糖尿病大鼠胃ghrelin m RNA表达水平显著升高(t=16.8,P<0.01),胃底ghrelin免疫活性细胞数量显著减少(t=3.98,P<0.01);实验中给予大鼠自由饮食,糖尿病大鼠血浆总ghrelin水平显著增加(t=7.53,P<0.01),nesfatin-1水平显著降低(t=5.46,P<0.01)。糖尿病大鼠注射胰岛素后,可使增加的ghrelin水平(t=1.76,P=0.11)和降低的nesfatin-1水平接近正常(t=1.96,P=0.06);且胰岛素可显著反转糖尿病大鼠胃总ghrelin(t=8.54,P<0.01)和nesfatin-1水平(t=2.42,P<0.05);以及注射胰岛素后,糖尿病大鼠胃底ghrelin细胞显著增加,nesfatin-1细胞明显减少(t=3.21,t=2.59,P<0.05)。结论:Ghrelin或nesfatin-1参与糖尿病大鼠能量平衡调控。  相似文献   
2.

Background

Anthropometric surveys devised by each country attempt to fulfill the requirements of the manufacturers, designers, and human welfare device production, providing them with data and tools and allowing them to face both the internal and export markets. To this end, national anthropometric data collections and comparisons including three-dimensional information, together with comparison of these data among countries, are conducted at both the domestic and global levels.

Methods

The anthropometric data of the Korean population measured in 2013 (Korean Agency for Technology and Standard (KATS) 2013 data) and the data collected from 2010 (KATS 2010 data) that was conducted on 710 males between the ages of 13 and 18 years were analyzed in this section to obtain information on Korean boy’s physical features and growth.

Results

The mean height increased about 5 cm from 13 to 14 years which shows the early fast maturing somatotype. Also, the mean height of boys aged from 15 to 16 increased about 1 to 2 cm. For the results of body proportion rate index against height, they show 0.93, 0.81, 0.38, 0.99, and 0.26 times the height in eye height, shoulder height, fingertip height, and span and maximum shoulder breadth, respectively, in 16-year-old boys. For the body mass index, the weight is increased from the age of 16 years.

Conclusions

There are several studies that cover growth features of the entire range from birth to maturity, and they have reported the comparison of the growth patterns among Europeans. Even though such researches have been made, as for the industry, the human modeling tools based on the anthropometric data and morphological features that cover all the countries should be developed for well-fit garments and other human-oriented design process.  相似文献   
3.
中国西北干旱区蒸散发时空动态特征   总被引:21,自引:9,他引:12  
邓兴耀  刘洋  刘志辉  姚俊强 《生态学报》2017,37(9):2994-3008
利用MODIS ET数据集中2000—2014年的地表实际蒸散发量产品,运用变异系数、Theil-Sen median趋势分析与MannKendall检验和Hurst指数法,研究了中国西北干旱区蒸散发的空间格局、不同维度的空间异质性和时间变化特征及未来趋势预测。结果表明:(1)2000—2014年全区蒸散发量总体较小,蒸散发量小于200 mm的区域占总面积的38.329%。在空间上ET自山区向两侧平原减少,不同土地覆盖的ET大小为:林地农用地草地稀疏植被。受降水和土地覆盖的综合影响,ET的高值区(400 mm)主要在降水丰富的山区林地和草地,而低值区(200 mm)主要在降水较少的平原稀疏植被区和草地。(2)近15年全区蒸散发变异程度不明显,以相对较低的波动变化为主。各亚区内波动较低区域的比例为:北疆天山祁连山内蒙西部河西走廊南疆。(3)15年间全区年均蒸散发量呈波动变化,总体有微弱的减小趋势,变化率为-0.9348 mm/a。基于像元尺度的分析也表明全区ET以减小的变化趋势为主,但各亚区的减小程度各异:天山内蒙西部河西走廊北疆祁连山,仅南疆有增加趋势。(4)全区ET的Hurst指数均值为0.689,Hurst指数大于0.5的范围所占比例为80.033%,未来全区蒸散发的变化趋势以持续性减小为主。其中22.003%区域的变化趋势无法确定。未来各亚区ET的减少趋势为:内蒙西部天山河西走廊北疆祁连山南疆。  相似文献   
4.
We have recently demonstrated that the PI3K class II-α isoform (PI3K-C2α), which generates phosphatidylinositol 3-phosphate and phosphatidylinositol 3,4-bisphosphates, plays crucial roles in angiogenesis, by analyzing PI3K-C2α knock-out mice. The PI3K-C2α actions are mediated at least in part through its participation in the internalization of VEGF receptor-2 and sphingosine-1-phosphate receptor S1P1 and thereby their signaling on endosomes. TGFβ, which is also an essential angiogenic factor, signals via the serine/threonine kinase receptor complex to induce phosphorylation of Smad2 and Smad3 (Smad2/3). SARA (Smad anchor for receptor activation) protein, which is localized in early endosomes through its FYVE domain, is required for Smad2/3 signaling. In the present study, we showed that PI3K-C2α knockdown nearly completely abolished TGFβ1-induced phosphorylation and nuclear translocation of Smad2/3 in vascular endothelial cells (ECs). PI3K-C2α was necessary for TGFβ-induced increase in phosphatidylinositol 3,4-bisphosphates in the plasma membrane and TGFβ receptor internalization into the SARA-containing early endosomes, but not for phosphatidylinositol 3-phosphate enrichment or localization of SARA in the early endosomes. PI3K-C2α was also required for TGFβ receptor-mediated formation of SARA-Smad2/3 complex. Inhibition of dynamin, which is required for the clathrin-dependent receptor endocytosis, suppressed both TGFβ receptor internalization and Smad2/3 phosphorylation. TGFβ1 stimulated Smad-dependent VEGF-A expression, VEGF receptor-mediated EC migration, and capillary-like tube formation, which were all abolished by either PI3K-C2α knockdown or a dynamin inhibitor. Finally, TGFβ1-induced microvessel formation in Matrigel plugs was greatly attenuated in EC-specific PI3K-C2α-deleted mice. These observations indicate that PI3K-C2α plays the pivotal role in TGFβ receptor endocytosis and thereby Smad2/3 signaling, participating in angiogenic actions of TGFβ.  相似文献   
5.
Larval cuticle ofHelicoverpa (Heliothis)zea and yeast extract added to a minimal medium (MM) induced germination of conidia ofNomuraea rileyi whereas sterile distilled water or MM alone did not. Yeast extract increased mycelial yield, but when cuticle was added, mycelial yield significantly decreased. Proteases and chitinases ofN. rileyi were only expressed when cuticle was added to the MM.This article reports the results of research only. Mention of a proprietary product in this paper does not constitute a recommendation for use by US Department of Agriculture.  相似文献   
6.
The effects of a high-growth genetic background on the growth of mice hemizygous for one of two growth hormone transgenes were examined. Male mice hemizygous for wild-type (W) and dwarf mutant (M) bovine growth hormone (bGH) transgenes were crossed with females of a high-growth selected (S) and control (C) line as follows: W x S, W x C, M x S and M x C. Body weights of progeny were recorded weekly from 2 to 10 weeks of age. F1 progeny were classified as carriers (P) or non-carriers (N) of the transgene by assaying tail DNA for bGH using the polymerase chain reaction and agarose gel electrophoresis. A deficiency in the number of f1 progeny carrying the W (P<0.05) and M (P<0.01) bGH transgene was most likely due to differential prenatal and early postnatal mortality. Bodyweight means of wild-type transgenic mice were larger (P < 0.05) than those of non-transgenic littermates by 3 weeks of age in a C background in contrast to 5 weeks in S. The wild-type bGH transgene increased adult body weights more in the C (155%) than in the S (136%) background, indicating transgene expression by selection background interaction (P < 0.05). However, the growth response to the wild-type transgene in the S background was still large. The dwarf mutant transgene had a greater effect on growth reduction in the S (70%) than in the C (84%) background, thus causing transgene expression by selection background interaction (P < 0.05). Gender by wild-type transgene effect interactions (P < 0.001) for adult body weight were caused by the transgene reducing the gender difference for body weight in C and eliminating it in S. The dwarf mutant caused a larger negative effect on growth in males than in females, resulting in a gender by dwarf mutant transgene interaction (P < 0.001) for adult body weights. Results indicate that the effect of a GH transgene on growth can be affected both by a high-growth genetic background and the gender of progeny.  相似文献   
7.
J. P. Hill  R. L. Malmberg 《Planta》1991,185(4):472-478
The growth of vegetative and reproductive shoots of Nicotiana tabacum L. cv. Xanthi is analyzed with the plastochron index to estimate the relationship between corolla growth and time. The plastochron of leaves 9 through 20 declines steadily at each successive node. The flower plastochron increases steadily during the growth of an individual cyme, with the most distal flower to open having the longest plastochron. Variation in the flower plastochron is the result of variation in the rate of flower initiation, not the growth rate of individual flowers. The corolla has an extended phase of approximately constant relative growth in length (between 0.2 · d–1 and 0.3 · d–1) until a peak of growth (0.5 · d–1) 2–3 d before anthesis. Corollas also have periodic peaks and troughs of growth that are low in amplitude (0.1 · d–1), but persist throughout most of corolla development. The pattern of corolla expansion contrasts strongly with earlier reports of the pattern of tobacco leaf growth.Abbreviations PI plastochron index - PR plastochron ratio - RGR relative growth rate in length The authors thank: Drs. T. Sage and E.G. Williams for the considerable time and space they invested; the members of Dr. R. Wyatt's laboratory for allowing us to use their computer facilities; A. Tull and M. Smith for their care taken in the green-house. This research was supported by U.S. Department of Agriculture grant GAM-89-01056 and by National Science Foundation grant DCB-87-15799.  相似文献   
8.
We studied the influences of food type, food quantity, water currents, starvation and light on growth and reproduction of the sea hareaplysia oculifera (Adams and Reeve, 1850) under laboratory conditions. Out of five species of algae served as food,Enteromorpha intestinalis promoted the fastest growth ofA. oculifera, Ulva spp. slower growth,Cladophora sp. allowed maintenance spp. slower growth,Cladophora sp. allowed maintenance of steady body mass, and the brown algaeColpomenia sp. andPadina pavonia were rejected by the sea hares. When sea hares were exposed to four levels of water currents, growth rates decreased as water currents increased. Sea hares fed on 50% ration grew slower than those fed on 100% ration (ad libitum). During 10 days of starvation sea hares lost weight, but when subsequently fed 100% ration they recovered and grew at a rate similar to those fed continuously with 100% ration. Under shade and under natural sunlight sea hares grew at the same rates. Whenever growth rates decreased, sea hares began to spawn at a smaller body size.A. oculifera demonstrated physiological plasticity that adapted them to varied and unpredictable environmental conditions. At different conditions of food availability they applied different tactics of resource allocation between growth and reproduction.  相似文献   
9.
Oncogenes,protein tyrosine kinases,and signal transduction   总被引:1,自引:0,他引:1  
Many oncogenes encode protein tyrosine kinases (PTKs). Oncogenic mutations of these genes invariably result in constitutive activation of these PTKs. Autophosphorylation of the PTKs and tyrosine phosphorylation of their cellular substrates are essential events for transmission of the mitogenic signal into cells. The recent discovery of the characteristic amino acid sequences, of thesrc homology domains 2 and 3 (SH2 and SH3), and extensive studies on proteins containing the SH2 and SH3 domains have revealed that protein tyrosine-phosphorylation of PTKs provides phosphotyrosine sites for SH2 binding and allows extracellular signals to be relayed into the nucleus through a chain of protein-protein interactions mediated by the SH2 and SH3 domains. Studies on oncogenes, PTKs and SH2/SH3-containing proteins have made a tremendous contribution to our understanding of the mechanisms for the control of cell growth, oncogenesis, and signal transduction. This review is intended to provide an outline of the most recent progress in the study of signal transduction by PTKs.  相似文献   
10.
We have developed a series of orally efficacious IRAK4 inhibitors, based on a scaffold hopping strategy and using rational structure based design. Efforts to tackle low permeability and high efflux in our previously reported pyrrolopyrimidine series (Scott et al., 2017) led to the identification of pyrrolotriazines which contained one less formal hydrogen bond donor and were intrinsically more lipophilic. Further optimisation of substituents on this pyrrolotriazine core culminated with the discovery of 30 as a promising in vivo probe to assess the potential of IRAK4 inhibition for the treatment of MyD88 mutant DLBCL in combination with a BTK inhibitor. When tested in an ABC-DLBCL model with a dual MyD88/CD79 mutation (OCI-LY10), 30 demonstrated tumour regressions in combination with ibrutinib.  相似文献   
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