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101.
The precursors of autoreactive T-lymphocytes (PARTL) have been detected in the spleen of mice infected with Langat virus. When introduced into syngeneic recipients, PARTL differentiate in their lymph nodes into autoreactive T-lymphocytes (ARTL) causing a fatal autoimmune disease in the syngeneic recipients in vivo and capable of destroying syngeneic cell cultures in vitro. In the thymus of mice infected with Langat virus T-suppressors (TS) inhibiting the differentiation of PARTL into ARTL have been detected. The serum of intact mice has been shown to contain the serum blocking factor (SBF) which suppresses the differentiation of PARTL and the activity of TS from donors having common H-2 haplotypes of the gene complex with serum donors. In the course of viral infection the decrease of SBF activity and, simultaneously, the activation of PARTL and TS occur. The activation of PARTL and TS in infected mice may be suppressed by the injection of the serum of intact donors identical in H-2 haplotypes. The injection of ARTL induced by Langat virus into syngeneic recipients infected with this virus provokes the transformation of asymptomatic infection into acute infection, while TS and SBF blocking the differentiation of PARTL protect the animals from death. 相似文献
102.
With a contact optical system it is possible to carry out intravital studies of neurons and other structures, stained with vital dyes in reflected light in a specially prepared specimen of the cat cerebral cortex. The high-quality characteristics of the optical system used have made combined morphological and intracellular electrophysiological investigations of these neurons possible. The nature of intravital morphological changes in cortical neurons was established in response to their puncture by microelectrodes with tips with different external diameters and configurations; certain morpho-functional correlations were found in the response of pyramidal neurons to disturbance of their temperature regime.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. Translated from Neirofiziologiya, Vol. 8, No. 2, pp. 122–125, March–April, 1976. 相似文献
103.
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105.
Recent technological advances have expanded and increased the resolution of studies in evolutionary biology, creating a need for a modern textbook that highlights the latest developments in the field. Evolutionary Genetics: Concepts, Analysis, and Practice, by Glenn‐Peter Sætre and Mark Ravinet (2019), as well as the book's accompanying online tutorials, provide a clear, up‐to‐date, and enjoyable introduction to evolutionary biology and genetics that explains fundamental evolutionary concepts, illustrates recent exciting findings, and offers hands‐on experience in analysing and interpreting genomic data. The book's accessible nature and emphasis on developing practical skills make it a valuable resource for undergraduate courses on evolutionary biology. 相似文献
106.
Chernysheva NB Tsyganov DV Philchenkov AA Zavelevich MP Kiselyov AS Semenov RV Semenova MN Semenov VV 《Bioorganic & medicinal chemistry letters》2012,22(7):2590-2593
A series of novel 4-oxa-podophyllotoxin derivatives 7 featuring the intact lactone ring D and various substituents in rings B and E has been synthesized and evaluated in a phenotypic sea urchin embryo assay along with the representative 4-aza-analogs 5 for their antimitotic and microtubule destabilizing activity. The most active compounds exhibited myristicin-derived or a 3',5'-dimethoxy substitution pattern in the ring E and a 6-methoxy moiety replacing the methylenedioxy ring A. Compounds 5xb, 5xe, 5yb, 7xa, 7xb, and 7xc showed potent antiproliferative effects in the NCI60 cytotoxicity screen. Notably, growth of the multi-drug resistant NCI/ADR-RES cells was more affected by these agents than the parent OVCAR-8 cell line. Although generally 4-oxa-podophyllotoxins were less potent than the respective 4-aza-derivatives in these assays, stability of the former series towards oxidation may prove to be of interest for the development of anticancer agents with in vivo activity. 相似文献
107.
Solov'ev KG Kurbatova EA Egorova NB Uspenskaia SN Tret'iakova AV Varfolomeev AN Gruber IM Efremova VN Akhmatova NK Diadizhshev NR Akhmatova IB Diadishchev NR Semenova IB Cherkasova LS Semenov BF Borovik RV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2006,(1):20-25
Used four schemes of the administration of the preparation with different time of the exposition of the animals in an aerosol chamber were tested with their subsequent intraperitoneal challenge with K. pneumoniae virulent strain K16. Irrespective of the number of immunization courses, the administration of the preparation made at intervals of 1 day, or daily, did not ensure any protective effect, but only led to an insignificant increase in their survival time in comparison with nonimmunized animals. After intervals between immunizations were increased to 3 days the protective effect of aerosol immumization was obtained (the survival rate was 65-80 % and considerably differed from that of the controls). The protective effect of aerosol immunization thus obtained was comparable with the effectiveness immunization made in a single subcutaneous injection. Aerosol immunization resulted in low antibody titers to the antigens contained in the vaccine, while after a single subcutaneous injection high antibody titers to Klebsiella and Proteus antigens were detected. The antigen-stimulated blast transformation of spleen lymphocytes in mice subjected to aerosol immunizations in 5 exposures was high. After subcutaneous immunization significant changes in such characteristics were detected on day 15. The data thus obtained were indicative of good prospects in the development Immunovac VP-4 as the medicinal form intended for use in aerosols. 相似文献
108.
Kiselyov AS Semenova M Semenov VV Piatnitski E 《Bioorganic & medicinal chemistry letters》2006,16(6):1726-1730
Novel potent derivatives of (azol-1-yl)methyl-N-arylbenzamides with improved solubility (>3mM) are described as ATP-competitive inhibitors of vascular endothelial growth factor receptor 2 (VEGFR-2). Many compounds display VEGFR-2 inhibitory activity reaching IC(50)<100 nM in the enzymatic assay. The compounds also inhibit the related tyrosine kinase, VEGFR-1, with similar potencies. Several compounds containing bulky lipophilic substituents at the benzamide pharmacophore yielded 10- to 17-fold selectivity for the VEGFR-2 versus VEGFR-1 kinase. 相似文献
109.
Alexander S. Kiselyov Marina Semenova Victor V. Semenov 《Bioorganic & medicinal chemistry letters》2009,19(5):1344-1348
Derivatives of (1,2,3-triazol-4-yl)benzenamines are described as potent and ATP-competitive inhibitors of vascular endothelial growth factor receptors I and II (VEGFR-1/2). A number of compounds exhibited VEGFR-2 and VEGFR-1 inhibitory activity comparable to that of Vatalanib? in both HTRF enzymatic and cellular assays. 相似文献
110.
Michael D. Wood Nicholas A. Beresford Dmitry V. Semenov Tamara L. Yankovich David Copplestone 《Radiation and environmental biophysics》2010,49(4):509-530
Reptiles are an important, and often protected, component of many ecosystems but have rarely been fully considered within
ecological risk assessments (ERA) due to a paucity of data on contaminant uptake and effects. This paper presents a meta-analysis
of literature-derived environmental media (soil and water) to whole-body concentration ratios (CRs) for predicting the transfer
of 35 elements (Am, As, B, Ba, Ca, Cd, Ce, Cm, Co, Cr, Cs, Cu, Fe, Hg, K, La, Mg, Mn, Mo, Na, Ni, Pb, Po, Pu, Ra, Rb, Sb,
Se, Sr, Th, U, V, Y, Zn, Zr) to reptiles in freshwater ecosystems and 15 elements (Am, C, Cs, Cu, K, Mn, Ni, Pb, Po, Pu, Sr,
Tc, Th, U, Zn) to reptiles in terrestrial ecosystems. These reptile CRs are compared with CRs for other vertebrate groups.
Tissue distribution data are also presented along with data on the fractional mass of bone, kidney, liver and muscle in reptiles.
Although the data were originally collected for use in radiation dose assessments, many of the CR data presented in this paper
will also be useful for chemical ERA and for the assessments of dietary transfer in humans for whom reptiles constitute an
important component of the diet, such as in Australian aboriginal communities. 相似文献