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991.
Studies have indicated that blood alcohol levels cycle exists when ethanol is fed continuously using the intragastric feeding rat model of early alcoholic liver disease. The aim of the present study was to determine the role played by catecholamines in the pathogenesis of the blood alcohol cycling observed when ethanol is fed at a constant rate. The rats were tested at the peaks and troughs of the urinary alcohol level (UAL) cycle and the results were compared with controls. Blood catecholamine levels were markedly increased at the peaks, but not at the troughs. Propranolol, a beta adrenergic blocker, attenuated the amplitude of the cycle. Phenoxybenzamine, an alpha blocker disrupted the cycle and elevated ethanol to fatal levels. The results indicate that both alpha and beta adrenergic mechanisms are required for the cycle to occur. 相似文献
992.
Photomutagenicity of 16 polycyclic aromatic hydrocarbons from the US EPA priority pollutant list 总被引:13,自引:0,他引:13
The photomutagenicity of 16 polycyclic aromatic hydrocarbons (PAHs), all on the United States Environmental Protection Agency (US EPA) priority pollutant list, was studied. Concomitant exposing the Salmonella typhimurium bacteria strain TA102 to one of the PAHs and light (1.1 J/cm2 UVA+2.1 J/cm2 visible) without the activation enzyme S9, strong photomutagenic response is observed for anthracene, benz[a]anthracene, benzo[ghi]perylene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, and pyrene. Under the same conditions, acenaphthene, acenaphthylene, benzo[k]fluoranthene, chrysene, and fluorene are weakly photomutagenic. Benzo[b]fluoranthene, fluoranthene, naphthalene, phenanthrene, and dibenz[a,h]anthracene are not photomutagenic. These results indicate that PAHs can be activated by light and become mutagenic in Salmonella TA102 bacteria. At the same time, the mutagenicity for all the 16 PAHs was examined with the standard mutagenicity test with 10% S9 as the activation system. Benzo[b]fluoranthene, benzo[k]fluoranthene, chrysene, acenaphthylene, and fluorene are weakly mutagenic, while the rest of the PAHs are not. In general, the photomutagenicity of PAHs in TA102 does not correlate with their S9-activated mutagenicity in either TA102 or TA98/TA100 since they involve different activation mechanisms. 相似文献
993.
Nie W O'Brien PC Fu B Wang J Su W Ferguson-Smith MA Robinson TJ Yang F 《American journal of physical anthropology》2006,129(2):250-259
Multidirectional chromosome painting with probes derived from flow-sorted chromosomes of humans (Homo sapiens, HSA, 2n = 46) and galagos (Galago moholi, GMO, 2n = 38) allowed us to map evolutionarily conserved chromosomal segments among humans, galagos, and slow lorises (Nycticebus coucang, NCO, 2n = 50). In total, the 22 human autosomal painting probes detected 40 homologous chromosomal segments in the slow loris genome. The genome of the slow loris contains 16 sytenic associations of human homologues. The ancient syntenic associations of human chromosomes such as HSA 3/21, 7/16, 12/22 (twice), and 14/15, reported in most mammalian species, were also present in the slow loris genome. Six associations (HSA 1a/19a, 2a/12a, 6a/14b, 7a/12c, 9/15b, and 10a/19b) were shared by the slow loris and galago. Five associations (HSA 1b/6b, 4a/5a, 11b/15a, 12b/19b, and 15b/16b) were unique to the slow loris. In contrast, 30 homologous chromosome segments were identified in the slow loris genome when using galago chromosome painting probes. The data showed that the karyotypic differences between these two species were mainly due to Robertsonian translocations. Reverse painting, using galago painting probes onto human chromosomes, confirmed most of the chromosome homologies between humans and galagos established previously, and documented the HSA 7/16 association in galagos, which was not reported previously. The presence of the HSA 7/16 association in the slow loris and galago suggests that the 7/16 association is an ancestral synteny for primates. Based on our results and the published homology maps between humans and other primate species, we propose an ancestral karyotype (2n = 60) for lorisiform primates. 相似文献
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997.
Soil organic carbon changes as influenced by agricultural land use and management: a case study in Yanhuai Basin, Beijing, China 下载免费PDF全文
The effects of agricultural land use and management practices on soil organic carbon (SOC) are of great concern. In this study, SOC changes were investigated in sandy loam soils (Ustochrepts, USDA Soil Taxonomy) under orchard, vegetable, corn (Zea maize L.), and soybean (Glycine max L.) cultivation in northern China. The corn fields were further classified into three categories based on their inputs, i.e. high-input, mid-input, and low-input corn fields. In April 2005, a total of 197 soil samples were collected from 42 soil sites within 100 cm soil depth in Yanhuai Basin, Beijing, China. SOC contents were determined using rapid dichromate oxidation, and ANOVA statistical analysis was used to test the significances between land use and management practices at p<0.05. The results showed that: (1) the effects of land use and management practices on SOC primarily occurred within the topsoil (0–25 cm), and the SOC contents sharply decreased with the increase in soil depth. (2) SOC content and density values of orchard, vegetable, and high-input corn fields were higher than those of soybean, mid- and low-input corn fields. 相似文献
998.
Using purified recombinant human ventricular myosin light chain 1 (HVMLC 1) as the antigen,three monoclonal antibodies,designated C8,C9 and B 12,were prepared.Immunoblot experiments demonstratedthat all monoclonal antibodies could react with the ventricular myosin light chain 1 isolated from differentsources,such as human,rat or pig.It was also demonstrated that C8 was directed against the NN part of theN-fragment (amino acid 1-40) of HVMLC1,and both C9 and B12 against the C-fragment (amino acid 99-195).The affinity constants of C8,C9 and B12 were 3.20×10~8,8.60×10~7 and 1.77×10~8 M~(-1),respectively,determined by non-competitive ELISA.The isotype of B12 was determined as lgG2a,whereas the isotype ofboth C8 and C9 were IgG1.In the presence of C9 or B12,the actin-activated Mg~(2 )ATPase activity of myosinwas greatly inhibited,but there was almost no effect on the Mg~(2 )ATPase activity for C8.B12 and C9 alsoinhibited the superprecipitation of porcine cardiac native actomyosin (myosin B) and reconstituted actomyosin,but C8 did not.The results indicate that all three monoclonal antibodies could bind the intact myosin molecule,but B12 and C9 might more easily react with epitopes located in the C-fragment of HVMLC1.The inhibitoryeffects of B 12 and C9 on ATPase activity and superprecipitation assays show that light chain 1,particularlythe C-fragment domain,is involved in the modulation of the actin-activated Mg~(2 )ATPase activity of myosinand,as a consequence,plays an essential role in the interaction of actin and myosin. 相似文献
999.
SCAR Makers and Multiplex PCR-Based Rapid Molecular Typing of Lentinula edodes Strains 总被引:1,自引:0,他引:1
Xueqian Wu Haibo Li Weiwei Zhao Lizhong Fu Huazheng Peng Liang He Junwen Cheng Hailong Wei Qingqi Wu 《Current microbiology》2010,61(5):381-389
Lentinula edodes is the second most important cultivated mushroom worldwide, the most commercial strains have been identified only through
traditional phenotypic analysis. In this study, a simple rapid PCR-based molecular method was developed for distinguishing
commercial strains of L. edodes by developing specific sequence characterized amplified region (SCAR) markers and establishing multiplex PCR assays with
the SCAR primers. Derived from the randomly amplified polymorphic DNA (RAPD) and sequence-related amplified polymorphism (SRAP)
techniques, 10 informative SCAR markers were generated from 10 polymorphic RAPD and SRAP bands. The differences in SCAR phenotypes
among different strains made these SCAR markers potentially useful to characterize 6 strains and identify them from other
studied strains. Moreover, different SCAR phenotypes also made the other 17 studied strains to be divided into four distinguishable
groups. The multiplex PCR assays were further established for the joint use of some SCAR markers efficiently. Compared with
some identification methods reported previously, the special feature of this new molecular method is technically rapid and
convenient in the practical use and suitable for analyzing large numbers of samples. Thus, the simple rapid PCR-based molecular
method can be used as a helpful assistant tool for the lentinula industry. To our knowledge, this study is the first to describe
a development of a new SCAR maker-based multiplex PCR assay for rapid molecular typing of edible mushroom. 相似文献
1000.
Hong Sui Yuxian Bai Kaibing Wang Xi Li Chun Song Fang Fu Yongxin Zhang Lejing Li 《Cancer immunology, immunotherapy : CII》2010,59(7):989-999