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941.
942.
Ming Li Wei Zhu Xiaoxuan Dai Man Xiao Gloria Appiah-Sefah Philip Nti Nkrumah 《Aquatic Ecology》2014,48(2):207-217
Microcystis was cultured under standard conditions in BG-11 and M-11 media. Using results of an analysis of RNA and total organic carbon (TOC) content, a significant logarithmic relationship between Microcystis growth rate and the RNA/TOC ratio was described to measure the growth rate. Colonial Microcystis samples collected in a shallow, hypertrophic lake (Lake Taihu, China) during May–November 2012 were divided into six size classes (<75, 75–100, 100–150, 150–300, 300–500, and >500 μm), and the RNA/TOC ratio of each class was analyzed to evaluate differences in growth. The growth rate of colonies in the 150–300-μm size class was highest from May to August, but the growth rate increased along with the increase in colony size from September to November. Our results also indicated that water temperature did not change the relationship between growth rate and colony size, but the growth rate of larger colonies was higher than the growth rate of smaller colonies at conditions of low total nitrogen, low total dissolved phosphorus concentration, and high light intensity. Taken together, these results suggest that large colonial Microcystis possess an advantage that is a consequence of this faster growth at lower nutrient concentrations and high light intensities. 相似文献
943.
Silke M. Currie Emily Gwyer Findlay Brian J. McHugh Annie Mackellar Tian Man Derek Macmillan Hongwei Wang Paul M. Fitch Jürgen Schwarze Donald J. Davidson 《PloS one》2013,8(8)
Respiratory syncytial virus is a leading cause of lower respiratory tract illness among infants, the elderly and immunocompromised individuals. Currently, there is no effective vaccine or disease modifying treatment available and novel interventions are urgently required. Cathelicidins are cationic host defence peptides expressed in the inflamed lung, with key roles in innate host defence against infection. We demonstrate that the human cathelicidin LL-37 has effective antiviral activity against RSV in vitro, retained by a truncated central peptide fragment. LL-37 prevented virus-induced cell death in epithelial cultures, significantly inhibited the production of new infectious particles and diminished the spread of infection, with antiviral effects directed both against the viral particles and the epithelial cells. LL-37 may represent an important targetable component of innate host defence against RSV infection. Prophylactic modulation of LL-37 expression and/or use of synthetic analogues post-infection may represent future novel strategies against RSV infection. 相似文献
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946.
Jing‐Rong Wang Chiu‐Yin Leung Hing‐Man Ho Stella Chai Lee‐Fong Yau Zhong‐Zhen Zhao Zhi‐Hong Jiang 《化学与生物多样性》2010,7(4):975-983
Quantitative comparison of seven ginsenosides in wild and cultivated American ginseng revealed that the Rg1/Rd ratio presented a significantly large difference between cultivated and type‐I (one of the defined chemotypes) wild American ginseng, facilitating this ratio as a characteristic marker for differentiating these two groups. Similarly, the ratio (Rg1+Re)/Rd, and the ratio of protopanaxatriol (PPT)‐type ginsenosides to protopanaxadiol (PPD)‐type ginsenosides showed a large difference between these two groups. On the other hand, type‐II wild samples were found to have high Rg1/Rb1 and Rg1/Re ratios and low panaxydol/panaxynol ratio, which is entirely different from Type‐I American ginseng, but is very similar to that of Asian ginseng. This not only suggests that the chemotype should be taken into consideration properly when using these parameters for differentiating American and Asian ginseng, but also indicates that type‐II wild American ginseng may have distinct pharmacological activities and therapeutic effects. 相似文献
947.
Shiyao Cao Zhuo Kang Yanhao Yu Junli Du Lazarus German Jun Li Xiaoqin Yan Xudong Wang Yue Zhang 《Liver Transplantation》2020,10(9)
Group III–V compound semiconductors are a promising group of materials for photoelectrochemical (PEC) applications. In this work, a metal assisted wet etching approach is adapted to acquiring a large‐area patterned microdome structure on p‐GaAs surface. In addition, atomic layer deposition is used to deposit a TiO2 protection layer with controlled thickness and crystallinity. Based on a PEC photocathode design, the optimal configuration achieves a photocurrent of ?5 mA cm?2 under ?0.8 V versus Ag/AgCl in a neutral pH electrolyte. The TiO2 coating with a particular degree of crystallization deposited via controlled temperature demonstrates a superior stability over amorphous coating, enabling a remarkably stable operation, for as long as 60 h. The enhanced charge separation induced by favorable band alignment between GaAs and TiO2 contributes simultaneously to the elevated solar conversion efficiency. This approach provides a promising solution to further development of group III–V compounds and other photoelectrodes with high efficiency and excellent durability for solar fuel generation. 相似文献
948.
Nisa M. Maruthur Man Li Marc K. Halushka Brad C. Astor James S. Pankow Eric Boerwinkle Josef Coresh Elizabeth Selvin Wen Hong Linda Kao 《PloS one》2015,10(6)
Plasma soluble Receptor for Advanced Glycation End-products (sRAGE) is a strong marker of vascular outcomes although evidence on the direction of association is mixed. Compared to whites, blacks have lower levels of sRAGE. We hypothesized that genetic determinants of sRAGE would help clarify the causal role of sRAGE and the black-white difference in sRAGE levels. We conducted a genome-wide analysis of sRAGE in whites and blacks from the Atherosclerosis Risk in Communities Study. Median plasma sRAGE levels were lower in blacks than whites (728 vs. 1067 pg/ml; P<0.0001). The T (vs. C) allele of rs2070600, a missense variant in AGER, the gene encoding RAGE, was associated with approximately 50% lower sRAGE levels in both whites (N = 1,737; P = 7.26x10-16; minor allele frequency (MAF) = 0.04) and blacks (N = 581; P = 0.02; MAF = 0.01). In blacks, the T (vs. C) allele of rs2071288, intronic to AGER, was associated with 43% lower sRAGE levels (P = 2.22x10-8; MAF = 0.10) and was nearly absent in whites. These AGER SNPs explained 21.5% and 26% of the variation in sRAGE in blacks and whites, respectively, but did not explain the black-white difference in sRAGE. These SNPs were not significantly associated with incident death, coronary heart disease, diabetes, heart failure, or chronic kidney disease in whites (N = 8,130–9,017) or blacks (N = 2,293–2,871) (median follow up ~20 years). We identified strong genetic determinants of sRAGE that did not explain the large black-white difference in sRAGE levels or clearly influence risk of clinical outcomes, suggesting that sRAGE may not be a causal factor in development of these outcomes. 相似文献
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950.