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991.
肿瘤患者痰培养中细菌谱及耐药性的研究 总被引:2,自引:0,他引:2
目的评价肿瘤患者治疗过程中细菌感染的病原种类分布及其耐药情况,从而达到为肿瘤患者的抗感染治疗提供依据。方法对321例肿瘤患者痰标本培养及药敏结果进行分析。结果321例肿瘤患者痰标本检出致病菌(含条件致病菌)435株,革兰阴性杆菌占69.7%,革兰阳性球菌占26.2%,念珠菌占4.1%.5种主要致病菌对常用的抗生素存在不同程度耐药.产超广谱β-内酰胺酶细菌18株,耐甲氧西林葡萄球菌9株。结论对于肿瘤患者的抗感染治疗.临床上应重视细菌的种类分布,细菌的耐药问题,合理使用抗生素。 相似文献
992.
泛素蛋白酶体途径及其对植物生长发育的调控 总被引:3,自引:1,他引:2
泛素蛋白酶体途径主要由泛素活化酶、泛素结合酶、泛素蛋白连接酶和26S蛋白酶体组成。泛素活化酶首先激活泛素分子,然后把泛素转移到泛素结合酶上。泛素结合酶结合泛素蛋白连接酶并把泛素转移到底物蛋白上使底物泛素化,或把泛素转移到泛素蛋白连接酶再使底物泛素化。泛素化的蛋白通常通过26S蛋白酶体进行降解。初步的研究结果表明,植物生长发育的很多方面受泛素蛋白酶体介导的蛋白降解途径的调控。 相似文献
993.
Kazuhisa Terashima Teruyuki Matsumoto Eiji Hayashi Shinji Kawasaki Yukitaka Fukumasa-Nakai 《Mycoscience》2006,47(6):336-346
An improved linkage map of Lentinula edodes (shiitake) was constructed with an HEGS (high-efficiency genome scanning) system. Two hundred twenty-one HEGS-derived amplified
fragment length polymorphism (AFLP-H) markers and 21 gene markers were developed and combined with 203 previously developed
sequencer-derived AFLP markers (AFLP-S markers) and 3 mating factor loci (A, Bα, and Bβ) to construct a comprehensive linkage analysis. As a result, a novel linkage map with 166 markers including 2 mating factors
(A and B), 10 HEGS-derived gene markers, 72 AFLP-H markers, and 82 AFLP-S markers was obtained. Of the total 448 markers, 273 could
not be located on a linear map and thus were assigned to linkage groups as accessory markers. The map covers a total length
of 1398.4 centimorgans (cM) with an average marker interval distance of 8.4 cM. The map consists of 11 linkage groups (LGs)
in agreement with our previous map, and 7 LGs among them were found to contain branched linkages, which may be the result
of reciprocal translocations representing dynamic reorganization of the shiitake genome. The previously reported linkage map
was improved in terms of number of markers, marker density, linear order of markers, and total map length.
Contribution no. 384 of the Tottori Mycological Institute 相似文献
994.
Nickel(II) complexes of N,N′-dimethyl-N,N′-bis(pyridyl-2yl-methyl)ethylene-diamine (L1), N,N′-dimethyl-N,N′-bis(pyridyl-2-ylmethyl)-1,2-diaminopropane (L2) and N,N′-dimethyl-N,N′-bis(pyridyl-2-ylmethyl)-1,3-diaminopropane (L3) were prepared and their spectroscopic and redox properties studied. The distorted octahedral structure was determined for [NiL3ClCH3OH](ClO4) by using X-ray crystallography. The electronic spectral behavior of the complexes at different pHs was analyzed; it is shown that a new band grew at the expense of the other band intensity in acid media. The redox properties of ligands and their complexes show the peaks of Ni(II) → Ni(III) and Ni(II) → Ni(0) as these were detected at low concentration while Ni(II) → Ni(I) process was detectable clearly at high concentration. Furthermore, the interaction studies of 2-mercaptoethanesulfonic acid as a simulator of coenzyme M reductase (CoM) with NiN4 chromophores are discussed. 相似文献
995.
996.
M. V. Churukanov 《Neurophysiology》2006,38(5-6):421-423
Manifestations of the central pain syndrome induced by applications of benzylpenicillin on the rat spinal cord were quantitatively
measured after injections of endogenous and exogenous cannabinoid agonists, anandamide and WIN 55,212-2. The analgesic effects
of those agents are described.
Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 492–494, September–December, 2006. 相似文献
997.
Xuejun Yu Gaixia Li Dan Xu Xueliang Dong Xiuxiang Qi Youquan Deng 《Acta Physiologiae Plantarum》2006,28(1):9-11
The cucumber cotyledon greening bioassay for cytokinins was modified by using 95% acetone-ethanol instead of 80% acetone as
extraction solvent. The cotyledons were extracted directly with a 2:1 (v/v) acetone-ethanol solution in dark for 24 hours,
omitting the homogenization and centrifugation operations of the previous bioassay. The modified bioassay is more convenient
and especially useful in screening cytokinin-active substance from a large number of samples. 相似文献
998.
Weidner Stanisław Każarnowicz Marta Frączek Ewa Amarowicz Ryszard Karamać Magdalena 《Acta Physiologiae Plantarum》2006,28(6):627-634
Some posttranslational processes that occur in embryos of germinating triticale caryopses treated with different concentrations
of abscisic acid (ABA) were examined. ABA increased the ratio of cytoskeleton-bound polysomes in the total population of polysomes
and depressed the share of free and membrane-bound polysomes. Using exogenous RNase, stability of the total polysomal population
as well as each polysomal fraction was investigated. The total extractable polysomes isolated from embryonic tissues of germinating
triticale caryopses treated with ABA were more stable than the polysomes isolated from the control sample caryopses. The contribution
of the polysomes that were not digested by RNase was increased by higher concentrations of ABA applied during germination.
At high concentrations of ABA (50, 100 μM), the quantitative contribution of polysomes in the total ribosomal fraction was
almost 100% of the amount of polysomes before digestion and the modifications observed consisted mainly of the shift of the
so-called heavy polysomes towards light polysomes, containing a few ribosomes. Within each polysomal population, cytoskeleton-bound
polysomes (CBP and CMBP) were the most stable, which may imply that the bonds between polysomes and these protein filaments,
created in all eukaryotic cells increased their stability. It is assumed that mRNAs are stabilised or destabilised by interaction
of proteins with their various sequences. A plant hormone may depress or elevate the quantities of these proteins, thus regulating
the stability of different mRNAs. The results confirm the multi-faceted mechanism of ABA-induced response, where one of the
constituents is the effect of ABA on the stability of mRNAs molecules. The co-ordinated regulation of mRNAs synthesis and
their stability provide plants with improved adaptability. 相似文献
999.
Céline Faugeron Jean-Claude Mollet Yannis Karamanos Henri Morvan 《Acta Physiologiae Plantarum》2006,28(6):557-565
Activities of two de-N-glycosylation enzymes, PNGase (peptide N
4(N-acetyl-glucosaminyl)asparagine amidase) and ENGase (endo N-acetyl-β-D-glucosaminidase), involved in the release of N-glycans from N-glycoproteins, were monitored in several organs of tomato plants (Lycopersicon esculentum, Mill., cv. Dombito) with a fluorescence-HPLC procedure using a resofurin-labelled N-glycopeptide substrate. PNGase and ENGase
activities were detected in every organ assayed but with quantitative differences. The highest activities were found in the
youngest parts of the plant, i.e. apical buds, flowers and leaf blades. PNGase activities were consistently higher than ENGase
activities (three-fold in average). Both de-N-glycosylation activities were associated with high levels of proteins and protease activities. During fruit growth and ripening,
these three parameters decreased notably. The ubiquitous detection of these enzyme activities in the different organs is probably
associated with the previously characterized unconjugated N-glycans in tomato. The possible role of PNGase and ENGase degradation
products (i.e. unconjugated N-glycans) are discussed in relation with their biological functions in plant development. 相似文献
1000.
Nicolas Rapin Can Kesmir Sune Frankild Morten Nielsen Claus Lundegaard Søren Brunak Ole Lund 《Journal of biological physics》2006,32(3-4):335-353
Over the past decade a number of bioinformatics tools have been developed that use genomic sequences as input to predict to
which parts of a microbe the immune system will react, the so-called epitopes. Many predicted epitopes have later been verified
experimentally, demonstrating the usefulness of such predictions. At the same time, simulation models have been developed
that describe the dynamics of different immune cell populations and their interactions with microbes. These models have been
used to explain experimental findings where timing is of importance, such as the time between administration of a vaccine
and infection with the microbe that the vaccine is intended to protect against. In this paper, we outline a framework for
integration of these two approaches. As an example, we develop a model in which HIV dynamics are correlated with genomics
data. For the first time, the fitness of wild type and mutated virus are assessed by means of a sequence-dependent scoring
matrix, derived from a BLOSUM matrix, that links protein sequences to growth rates of the virus in the mathematical model.
A combined bioinformatics and systems biology approach can lead to a better understanding of immune system-related diseases
where both timing and genomic information are of importance. 相似文献