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991.
Sonal Setya Tushar Madaan Mohammad Tariq B. K. Razdan Sushama Talegaonkar 《AAPS PharmSciTech》2018,19(2):573-589
In the present study, the potential of transdermal nanoemulsion gel of selegiline hydrochloride for the treatment of Parkinson’s disease was investigated. Water-in-oil nanoemulsions were developed by comparing low- and high-energy methods and were subjected to thermodynamic stability tests, in vitro permeation, and characterization studies. In vitro studies indicated that components of nanoemulsion acted as permeation enhancers with highest flux of 3.531 ± 1.94 μg/cm2/h from nanoemulsion SB6 containing 0.5 mg selegiline hydrochloride, 3% distilled water, 21% S mix (Span 85, Tween 80, PEG 400), and 76% isopropyl myristate by weight. SB6 with the least droplet size of 183.4 ± 0.35 nm, polydispersity index of 0.42 ± 0.06 with pH of 5.9 ± 0.32 and viscosity of 22.42 ± 0.14 cps was converted to nanoemulsion gel NEGS4 (viscosity = 22,200 ± 400 cps) by addition of Viscup160® for ease of application and evaluated for permeation, safety, and pharmacokinetic profile in Wistar rats. It provided enhancement ratio 3.69 times greater than conventional gel. NEGS4 showed 6.56 and 5.53 times increase in bioavailability in comparison to tablet and conventional gel, respectively, along with sustained effect. Therefore, the developed water-in-oil nanoemulsion gel promises to be an effective vehicle for transdermal delivery of selegiline hydrochloride. 相似文献
992.
Hyunwoo Jeon Sharad Sarak Sang-Hyuk Lee Han-Seop Bea Mahesh Patil Geon-Hee Kim Byung-Gee Kim Jong In Won Hyungdon Yun 《Biotechnology and Bioprocess Engineering》2018,23(5):481-489
Optically pure amines, β-amino acids and γ-amino acids are the valuable precursors to produce biologically active compounds. The ω-TAs are the class of enzymes which are widely used to produce such compounds. In this work (S)-ω-transaminase from the thermophilic eubacterium Sphaerobacter thermophilus (St-TA) was fused with Elastin-like polypeptides (ELPs) through the cloning process and expressed in E. coli cells. The characterization of this fusion complex was performed with respect to thermostability and effect of DMSO. Where in case of St-TA-ELP-V60, major difference in the transition temperature (Tt) was observed, wherein a Tt of 38 and 70°C was observed at the increasing concentration of DMSO from 5 to 25% (v/v). Interestingly, these fusion proteins the activity was preserved even after the aggregation of fusion complex at Tt. The substrate specificity and product inhibition analysis showed that ω-TA-ELPs had comparable results as that of wild type ω-TA. Moreover, the fused ω-TA could be efficiently reused for up to 20 batches of transamination reaction. Furthermore, the applicability of the fusion protein for the production of a sitagliptin precursor (R)-3-amino-4-(2,4,5-triflurophenyl) butanoic acid (3-ATfBA) was evaluated, wherein 3-ATfBA was synthesized with good conversion (65%). 相似文献
993.
Actin cytoskeleton in intact and wounded coenocytic green algae 总被引:5,自引:0,他引:5
J. W. La Claire II 《Planta》1989,177(1):47-57
Summary The subcellular distribution of actin was investigated in two related species of coenocytic green algae, with immunofluorescence microscopy. Either no, or fine punctate fluorescence was detected in intact cells of Ernodesmis verticillata (Kützing) Børgesen and Boergesenia forbesii (Harvey) Feldmann. A reticulate pattern of fluorescence appears throughout the cortical cytoplasm of Ernodesmis cells shortly after wounding; this silhouettes chloroplasts and small vacuoles. Slender, longitudinal bundles of actin become evident in contracting regions of the cell, superimposed over the reticulum. Thicker portions of the bundles were observed in well-contracted regions, and the highly-convoluted appearance of nearby cortical microtubules indicates contraction of the bundles in these thicker areas. Bundles are no longer evident after healing; only the reticulum remains. In Boergesenia, a wider-mesh reticulum of actin develops in the cortex of wounded cells, which widens further as contractions continue. Cells wounded in Ca2+-free medium do not contract, and although the actin reticulum is apparent, no actin bundles were ever observed in these cells. Exogenously applied cytochalasins have no effect on contractions of cut cells or extruded cytoplasm, and normal actin-bundle formation occurs in treated cells. In contrast, erythro-9-[3-(2-hydroxynonyl)]adenine (EHNA) completely inhibits longitudinal contractions in wounded cells, and few uniformly slender actin bundles develop in inhibited cells. These results indicate that wounding stimulates a Ca2+-dependent, hierarchical assembly of actin into bundles, whose assembly and functioning are inhibited by EHNA. Contraction of the bundles and concomitant wound healing are followed by cessation of motility and disassembly of the bundles. The spatial and temporal association of the bundles with regions of cytoplasmic contraction, indicates that the actin bundles are directly involved in wound-induced cytoplasmic motility in these algae.Abbreviations EHNA
erythro-9-[3-(2-hydroxynonyl)]adenine
- MT(s)
microtubule(s) 相似文献
994.
995.
Feng Wang Xue-Rong Xiong Chun-Zhao Liu 《In vitro cellular & developmental biology. Plant》2009,45(3):342-349
With rapid economic development, energy consumption in China has tripled in the past 20 yr, exceeding 2.4 billion tons of
standard coal in 2006. The search for new green energy as substitutes for the nonrenewable energy resources has become an
urgent task. China has a variety of climates and is rich in potential biofuel plant species. Corn and cassava are used as
the main raw materials for bioethanol production in China. At the end of 2005, bioethanol productivity had increased to 1.02
million tons produced by four companies, and bioethanol-blended petrol accounted for 20% of the total petrol consumption in
China. According to the Mid- and Long-term Development Plan for Renewable Energy, the consumption of biodiesel in China will
reach 0.2 million tons in 2010 and 2.0 million tons in 2020. This review is intended to provide an introduction to the distribution
and development of biofuel crops and biofuel industry in China. 相似文献
996.
Yong Liu Ronglei Liu Liangchen Ye Jun Liang Fujun Xuan Qianghua Xu 《Hydrobiologia》2009,618(1):125-137
Portunus trituberculatus is a commercially important species widely spread in the East China Sea. Intraspecific variation of the mitochondrial DNA
cytochrome oxidase subunit I (mtDNA COI) gene was investigated in 213 individuals from six localities (Changjiang Estuary,
Shengsi Islands, Zhoushan Islands, Dongtou Islands, Dinghai Bay, and Quanzhou Bay) ranging from north (31°21′N) to south (24°55′N)
coastal waters of the East China Sea. Overall, a total of 27 mtDNA haplotypes and 21 variable sites were detected in the 787 bp
segment of COI gene. Analysis of mtDNA COI sequence data revealed that crabs from the six localities were characterized by
moderately high haplotypic diversity (h = 0.787 ± 0.026), while sequence divergence values between haplotypes were relatively low (π = 0.00241 ± 0.00098). Each population
was characterized by a single most frequent haplotype, shared among all six localities, and a small number of rare ones, typically
present in only one or two individuals and representative of a specific population. However, neither the neighbor-joining
tree nor the minimum spanning network (MSN) based on the haplotype data exhibited geographical patterns of the six populations.
Mismatch distribution analysis of P. trituberculatus individuals sampled from the six localities suggested that sudden population expansion might have occurred in CJ and SS population
that might be consistent with over-exploitation of the swimming crab. Analysis of molecular variance (AMOVA) and F
ST statistics showed that significant genetic differentiation existed among the SS, ZS, DT, DH, and QZ populations, suggesting
that gene flow might be reduced, even between the geographically close sites, despite the high potential of dispersal. The
possible causes of the observed genetic heterogeneity among the P. trituberculatus populations and the potential applications of the mtDNA COI marker in the artificial breeding and fisheries management are
discussed.
Handling editor: C. Sturmbauer 相似文献
997.
998.
Relations of mineral-soil C and N to climate and texture: regional differences within the conterminous USA 总被引:4,自引:0,他引:4
Soil is a prominent component of terrestrial C and N budgets. Soil C and N pools are influenced by, and may reciprocally influence,
many environmental factors. Our objective was to determine the quantitative relations of surface mineral-soil organic C, N,
and C/N ratios to climate and soil texture across seven ecological regions that make up the conterminous USA. Up to 608 soil
profiles per region and their corresponding climates were evaluated with regression analysis. The organic C pool (kg C m−2) in the upper 20 cm of mineral soil was positively related to mean annual precipitation, evapotranspiration and clay content
in all regions. It was negatively related to a temperature/precipitation index in all regions and negatively related to mean
annual temperature, except in the northwest temperate forest region. Soil C/N ratios were negatively related to clay or silt
content in all regions. These relations are consistent with concepts of moisture and temperature controls on detrital production,
differential effects of temperature on detrital production and decomposition, and stabilization of organic matter by clay
and silt. Differences in quantitative relations among regions may be related to vegetation-composition effects on soil organic
matter processes, clay mineralogy, and faunal mixing of surface organic horizons with mineral soil. Regional differences also
occurred in the importance of climate vs. soil texture in explaining the variability in soil C. The regional differences indicate
the importance of using region-specific, rather than generalized, equations for projecting long-term soil responses to climate
change and for conducting ecosystem-model calibration or validation. 相似文献
999.
Endostatin gene therapy enhances the efficacy of paclitaxel to suppress breast cancers and metastases in mice 总被引:5,自引:0,他引:5
Li J Dong X Xu Z Jiang X Jiang H Krissansen GW Sun X 《Journal of biomedical science》2008,15(1):99-109
Chemotherapy combined with antiangiogenic therapy is more effective than chemotherapy alone. The aim of this study was to
investigate whether endostatin, a potent anti-angiogenic agent, could enhance the efficacy of paclitaxel to combat breast
cancer. An expression plasmid encoding mouse endostatin (End-pcDNA3.1) was constructed, which produced intense expression
of endostatin and inhibited angiogenesis in the chorioallantoic membrane assay. 4T1 breast tumors were established in BALB/c
mice by subcutaneous injection of 1 × 105 4T1 cells. The End-pcDNA3.1 plasmid diluted in the transfection reagent FuGENETM was injected into the tumors (around 100 mm2), and paclitaxel was injected i.p. into the mice. Endostatin gene therapy synergized with paclitaxel in suppressing the growth
of 4T1 tumors and their metastasis to the lung and liver. Both endostatin and paclitaxel inhibited tumor angiogenesis and
induced cell apoptosis. Despite the finding that endostatin was superior to paclitaxel at inhibiting tumor angiogenesis, paclitaxel
was nevertheless more effective at inducing tumor apoptosis. The combination of paclitaxel and endostatin was more effective
in suppressing tumor growth, metastases, angiogenesis, and inducing apoptosis than the respective monotherapies. The combinational
therapy with endostatin and paclitaxel warrants future investigation as a therapeutic strategy to combat breast cancer. 相似文献
1000.
Mechanocomputational techniques in conjunction with artificial intelligence (AI) are revolutionizing the interpretations of the crucial information from the medical data and converting it into optimized and organized information for diagnostics. It is possible due to valuable perfection in artificial intelligence, computer aided diagnostics, virtual assistant, robotic surgery, augmented reality and genome editing (based on AI) technologies. Such techniques are serving as the products for diagnosing emerging microbial or non microbial diseases. This article represents a combinatory approach of using such approaches and providing therapeutic solutions towards utilizing these techniques in disease diagnostics. 相似文献