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991.
992.
Yuichi Moriguchi Atsushi Terazono 《The International Journal of Life Cycle Assessment》2000,5(5):281-286
We developed a simplified emission dispersion and exposure-assessment model designed to reflect the site-specific health impacts
of air pollution in life-cycle impact assessment (LCIA). We proposed an EXposure Per Emission Coefficient (EXPEC), a dimensionless
parameter representing the relative amount of pollutant inhaled per emission. EXPEC values were calculated for two typical
source categories - electric power plants and road vehicles — on a concentric circle model. The EXPEC values were significantly
different for different locations and source categories. We examined the application of EXPEC in a case study that compared
the effects of emissions from electric and gasoline-engine vehicles. EXPEC is a useful tool for assessing spatially differentiated
potential impacts. 相似文献
993.
Duane A. Tolle David P. Evers Bruce W. Vigon John J. Sheehan 《The International Journal of Life Cycle Assessment》2000,5(6):374-384
This study provides a benchmark of the life cycle environmental impact characteristics associated with a typical soybased
ink used for sheetfed lithographic printing. The scope ineluded a streamlined Life Cycle Inventory (LCI) and Impact Assessment
(LCIA). Materials, processes, and life cycle stages that are the same between different printing inks, or were less than one
percent by mass of the printing system input materials, were excluded. The LCIA included identification of specific processes
in the life cycle of soy-based ink printing that make the greatest contribution to the overall environmental hazard potential
in 13 impact categories for the baseline printing system selected. The LCIA approach included both regional scaling for areas
that differ in sensitivity to certain impact indicators and normalization against a reference value. Reduction in the use
of tall oil rosin and switching from conventional to low or no-till farming appear to be promising opportunities for reducing
the environmental hazard potential. 相似文献
994.
脂肪酶在微乳液和微乳液凝胶中催化辛酸辛醇的酯化反应 总被引:4,自引:0,他引:4
脂肪酶在合成反应中具有很高的区域选择性和立体选择性 ,已广泛用于食品工业和药物工业[1,2 ] ,在有机介质中的脂肪酶催化反应已有较多研究[3 ,4 ] 。微乳液一般由表面活性剂、助表面活性剂、油和水等组份组成 ,它是一种热力学稳定、光学透明、宏观均匀而微观不均匀的体系 ,能提供酶催化所需要的巨大油 /水界面[5] 。而将脂肪酶增溶于油包水(W /O)微乳液中的纳米级“水池”中 ,可使酶以分子水平分散[6] ,图 1(a) ,从而可用来模拟细胞微环境中的反应。油包水微乳液中的酶可通过加入明胶而制成固定化酶 ,含明胶的微乳液凝胶 (MBGs)最早… 相似文献
995.
Guangbing Hu Zhian Cheng Zizhuo Wu Hanyu Wang 《Journal of cellular biochemistry》2019,120(8):13554-13561
Due to high rates of metastasis and poor clinical outcomes for patients, it is important to study the pathomechanisms of osteosarcoma. However, due to the fact that osteosarcoma shows significant interindividual variation and high heterogeneity, the identification of differentially expressed genes (DEGs) at the population level cannot answer many important questions related to osteosarcoma tumorigenesis. Therefore, a new strategy to identify dysregulated genes in osteosarcoma samples is required. The aim of this study was to improve our understanding of osteosarcoma pathogenesis by identifying genes with universal aberrant expression in osteosarcoma samples. Because the relative expression ordering of genes is stable in normal bone tissues but is disrupted in osteosarcoma tissues, we used the RankComp algorithm to identify DEGs in normal and osteosarcoma tissue samples. We then calculated the dysregulation frequency for each gene. Genes with deregulation frequencies above 80% were deemed to be universal DEGs. Next, coexpression, pathway enrichment, and protein-protein interaction network analyses were performed to characterize the functions of these genes. From 188 samples of osteosarcoma obtained from four datasets measured on different platforms, 51 universal DEGs were identified, including 4 universally upregulated genes and 47 universally downregulated genes. Genes that were differentially coexpressed with these universal DEGs were found to be enriched in 46 cancer-related pathways. In addition, functional and network analyses showed that genes with high dysregulation frequencies were involved in cancer-related functions. Thus, the commonly aberrant genes identified in osteosarcoma tissues may be important targets for osteosarcoma diagnosis and therapy. 相似文献
996.
997.
Run-Hao Jiang Chen-Jiang Wu Xiao-Quan Xu Shan-Shan Lu Qing-Quan Zu Lin-Bo Zhao Jun Wang Sheng Liu Hai-Bin Shi 《Journal of cellular physiology》2019,234(2):1354-1368
In recent years, studies have shown that the secretome of bone marrow mesenchymal stromal cells (BMSCs) contains many growth factors, cytokines, and antioxidants, which may provide novel approaches to treat ischemic diseases. Furthermore, the secretome may be modulated by hypoxic preconditioning. We hypothesized that conditioned medium (CM) derived from BMSCs plays a crucial role in reducing tissue damage and improving neurological recovery after ischemic stroke and that hypoxic preconditioning of BMSCs robustly improves these activities. Rats were subjected to ischemic stroke by middle cerebral artery occlusion and then intravenously administered hypoxic CM, normoxic CM, or Dulbecco modified Eagle medium (DMEM, control). Cytokine antibody arrays and label-free quantitative proteomics analysis were used to compare the differences between hypoxic CM and normoxic CM. Injection of normoxic CM significantly reduced the infarct area and improved neurological recovery after stroke compared with administering DMEM. These outcomes may be associated with the attenuation of apoptosis and promotion of angiogenesis. Hypoxic preconditioning significantly enhanced these therapeutic effects. Fourteen proteins were significantly increased in hypoxic CM compared with normoxic CM as measured by cytokine arrays. The label-free quantitative proteomics analysis revealed 163 proteins that were differentially expressed between the two groups, including 107 upregulated proteins and 56 downregulated proteins. Collectively, our results demonstrate that hypoxic CM protected brain tissue from ischemic injury and promoted functional recovery after stroke in rats and that hypoxic CM may be the basis of a potential therapy for stroke patients. 相似文献
998.
A polyclonal antiserum was raised against highly purified RNA polymerase II from soybean embryos. Pure RNA polymerase II was fractionated on sodium dodecyl sulfate-polyacrylamide gels and transferred onto nitrocellulose sheets, incubated with the immune antiserum and then with iodinated protein A. Autoradiograms showed that the immune antiserum recognized all subunits of RNA polymerase II. Subunits 42, 27 and 16 kdalton were particularly reactive. Application of this transfer technique to protein extracts from soybean embryos or from cultured soybean cells allowed the identification of subunits of RNA polymerase II in the extracts. Analysis of the staining of the bands on the autoradiograms for increasing amounts of pure RNA polymerase II demonstrated that the transfer was quantitative, so that standard curves could be drawn to estimate the unknown amounts of enzyme in the extracts.Abbreviations DEAE
diethylaminoethyl
- SDS
sodium dodecyl sulfate 相似文献
999.
A.G. MacDonald 《生物化学与生物物理学报:生物膜》1984,775(2):141-149
Tetrahymena was grown at up to 260 atm to see if the bilayer-ordering effect of pressure increased the proportion of unsaturated fatty acids in the membrane lipids. Both whole cells and microsomes showed no such change in their fatty acid composition. The most striking effect was seen in the former which showed a pressure-dependent increase in the proportion of C16:0 in relation to C16:Δ9. Homeoviscous adaptation to pressure does not appear to occur in this cell. 相似文献
1000.
Eugene R. Zabarovsky Ilya M. Chumakov Vladimir S. Prassolov Lev L. Kisselev 《Gene》1984,30(1-3):107-111
We have determined the nucleotide sequence of an 841-bp fragment derived from a segment of the human genome previously cloned by Chumakov et al. [Gene 17 (1982) 19–26] and Zabarovsky et al. [Gene 23 (1983) 379–384] and containing regions homologous to the viral mos gene probe. This sequence displays homology with part of the coding region of the human and murine c-mos genes, contains several termination codons, and is interrupted by two Alu-family elements flanked by short direct repeats. Probably, the progenitor of the human c-mos gene was duplicated approximately at the time of mammalian divergence, was converted to a pseudogene, and acquired insertions of two Alu elements. 相似文献