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1.
Summary The adrenergic innervation of the pulmonary vasculature of the file snake Acrochordus granulatus was examined by use of glyoxylic acid-induced fluorescence. Perivascular plexuses of blue-green fluorescent nerves are observed around the common pulmonary artery, the anterior and posterior pulmonary arteries, the arterioles leading to the gas exchange capillaries of the lung, the venules draining the lung, and the anterior and posterior pulmonary veins. Adrenergic nerves are also associated with the visceral smooth muscle of the lung septa and other tissues. Thus, adrenergic control of pulmonary blood flow may occur either at the common pulmonary artery or more regionally within the lung. Regional control of blood flow in the elongate lung of this snake may be important in matching pulmonary perfusion with the distribution of respiratory gas. Glyoxylic acid-histochemistry and immunohistochemistry revealed that populations of cells located in the common pulmonary artery contain the indoleamine 5-hydroxy-tryptamine. Many of the cells are intimately associated with varicose blue-green fluorescent nerves. It is proposed that the 5-hydroxytryptamine-containing cells may be involved in intravascular chemoreception. 相似文献
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S. S. Papiha S.M.S. Chahal D. F. Roberts I. P. Singh 《American journal of physical anthropology》1980,53(2):275-283
Data are presented on serological and electrophoretic variants of 18 systems of red cells in 228 individuals belonging to a scheduled tribe (Kanet) and a scheduled caste (Koli) of Kinnar district in Himachal Pradesh, India. Differences in gene frequencies clearly indicate biological distinction in the local population. The possible cause of this genetic heterogeneity is discussed. 相似文献
4.
A. S. Wiener E. B. Gordon W. W. Socha J. Moor-Jankowski 《American journal of physical anthropology》1972,37(2):301-310
A series of 60 chimpanzees (Pan troglodytes) were tested for their human-type A-B-O blood groups and for ten simian-type blood factors. Of the 60 chimpanzees four were group O and 56 group A; combining this with our previous results, among 274 chimpanzees there were 36 group O and 238 group A. Gene frequency analysis of the V-A-B types (determined by three antisera, anti- V c, anti- A c and anti- B c) of the 60 chimpanzees indicated inheritance by four allelic genes, namely, the amorphic gene v and the three additional alleles vA, vB and V. This theory allows for the existence of ten genotypes but only seven V-A-B phenotypes, since the type V.AB is excluded. Gene frequency analysis confirmed that Cc and cc are contrasting antigens determined by corresponding allelic genes. The distribution of the C-c-E-F types among the 60 chimpanzees, as well as among 133 chimpanzees previously tested, is compatible with the postulation of five allelic genes, namely, the amorph c, and the alleles CE, CF, CEF and the very rare allele C. The blood factor G c appears to define a separate blood group system, independent of the V-A-B and C-E-F systems. The newly defined blood factor Lindsay appears to be related to the V-A-B system, while factor H c may be related to the C-E-F system. 相似文献
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David R. Jansen Gerard C. Krijger Judith Wagener Ratanang M. Senwedi Kenneth Gabanamotse Mpho Kgadiete Zvonimir I. Kolar Jan Rijn Zeevaart 《Journal of inorganic biochemistry》2009,103(9):1265-1272
In an attempt to elucidate the in vivo stability of the prospective radiopharmaceutical [117mSn]Sn(IV)-PEI-MP, where PEI-MP stands for N,N′,N′-trimethylenephosphonate-polyethyleneimine, glass electrode potentiometry was used to determine the stability constants of the Sn4+ ion as complexed with a variety of physiological amino acids. In addition, linear free energy relationship (LFER) correlation plots were used to extrapolate the constants of the major blood plasma ligands, based on data from Cu2+, Pb2+, and Zn2+. In so doing, a thermodynamic model of blood plasma was established for Sn4+ from which the complexation tendencies of Sn4+ were predicted in the event of the intravenous administration of such a drug. It was found that the Sn(IV)-PEI-MP could succumb to competition by the glutamine amino acid, which forms more stable complex(es), whilst the PEI-MP gets taken up largely by Ca2+. Also, this study shows the value of the in vitro experiments and modeling performed for radiopharmaceutical research and for attempts to reduce the number of animal experiments. 相似文献
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The drug discovery and development processes are divided into different stages separated by milestones to indicate that significant progress has been made and that certain criteria for target validation, hits, leads and candidate drugs have been met. Proteomics is a promising approach for the identification of protein targets and biochemical pathways involved in disease process and thus plays an important role in several stages of the drug development. The blood–brain barrier is considered as a major bottleneck when trying to target new compounds to treat neurodegenerative diseases. Based on the survey of recent findings and with a projection on expected improvements, this report attempt to address how proteomics participates in drug development. 相似文献
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Kristina Warton Vita Lin Tina Navin Nicola J Armstrong Warren Kaplan Kevin Ying Brian Gloss Helena Mangs Shalima S Nair Neville F Hacker Robert L Sutherland Susan J Clark Goli Samimi 《BMC genomics》2014,15(1)
Background
Free circulating DNA (fcDNA) has many potential clinical applications, due to the non-invasive way in which it is collected. However, because of the low concentration of fcDNA in blood, genome-wide analysis carries many technical challenges that must be overcome before fcDNA studies can reach their full potential. There are currently no definitive standards for fcDNA collection, processing and whole-genome sequencing. We report novel detailed methodology for the capture of high-quality methylated fcDNA, library preparation and downstream genome-wide Next-Generation Sequencing. We also describe the effects of sample storage, processing and scaling on fcDNA recovery and quality.Results
Use of serum versus plasma, and storage of blood prior to separation resulted in genomic DNA contamination, likely due to leukocyte lysis. Methylated fcDNA fragments were isolated from 5 donors using a methyl-binding protein-based protocol and appear as a discrete band of ~180 bases. This discrete band allows minimal sample loss at the size restriction step in library preparation for Next-Generation Sequencing, allowing for high-quality sequencing from minimal amounts of fcDNA. Following sequencing, we obtained 37×106-86×106 unique mappable reads, representing more than 50% of total mappable reads. The methylation status of 9 genomic regions as determined by DNA capture and sequencing was independently validated by clonal bisulphite sequencing.Conclusions
Our optimized methods provide high-quality methylated fcDNA suitable for whole-genome sequencing, and allow good library complexity and accurate sequencing, despite using less than half of the recommended minimum input DNA.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-476) contains supplementary material, which is available to authorized users. 相似文献9.
Majumder R Liang X Quinn-Allen MA Kane WH Lentz BR 《The Journal of biological chemistry》2011,286(41):35535-35542
Constituents of platelet membranes regulate the activity of the prothrombinase complex. We demonstrate that membranes containing phosphatidylcholine and phosphatidylethanolamine (PE) bind factor Va with high affinity (K(d) = ~10 nm) in the absence of phosphatidylserine (PS). These membranes support formation of a 60-70% functional prothrombinase complex at saturating factor Va concentrations. Although reduced interfacial packing does contribute to factor Va binding in the absence of PS, it does not correlate with the enhanced activity of the Xa-Va complex assembled on PE-containing membranes. Instead, specific protein-PE interactions appear to contribute to the effects of PE. In support of this, soluble C6PE binds to recombinant factor Va(2) (K(d) = ~6.5 μm) and to factor Xa (K(d) = ~91 μm). C6PE and C6PS binding sites of factor Xa are specific, distinct, and linked, because binding of one lipid enhances the binding and activity effects of the other. C6PE triggers assembly (K(d)(app) = ~40 nm) of a partially active prothrombinase complex between factor Xa and factor Va(2), compared with K(d)(app) for C6PS ~2 nm. These findings provide new insights into the possible synergistic roles of platelet PE and PS in regulating thrombin formation, particularly when exposed membrane PS may be limiting. 相似文献
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《Redox report : communications in free radical research》2013,18(6):223-229
AbstractNicotinamide adenine dinucleotide phosphate (NADPH) oxidase is upregulated in a variety of tissues in obesity. It is still unclear as to whether NADPH oxidase upregulation in a specific tissue is part of a systemic response. Here we analyzed the expression pattern of NADPH oxidase in vascular, adipose, and kidney tissues in a rat model of diet-induced obesity. After weaning, rats were fed either a normal or high-fat diet for 12 weeks. The high-fat diet resulted in 20% increased body weight. In the aorta, Nox4 expression was increased by three-fold in obese rats. Upregulations of p22phox and p47phox in adipose, and Nox4, p22phox, and p47phox in kidney were observed in obesity. Marked increases in plasma leptin and insulin were observed, with more modest changes in adiponectin in obese rats. The average systolic blood pressure in the obese group was 11 mmHg higher than that of lean rats (P < 0.005). There was a significant correlation between blood pressure and aortic Nox4 expression (P < 0.01). In cultured vascular smooth muscle cells, adiponectin reduced the expression of Nox4 in a protein kinase A-dependent manner. Our results suggest that upregulation of NADPH oxidase in multiple tissues during obesity appears to be a systemic response. At least in vitro, adiponectin may have a protective antioxidant role by suppressing vascular NADPH oxidase expression. The association between NADPH oxidase Nox4 expression in the vasculature and the elevated blood pressure in obesity requires further investigation. 相似文献