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871.
Ceravolo GS Franco MC Carneiro-Ramos MS Barreto-Chaves ML Tostes RC Nigro D Fortes ZB Carvalho MH 《Life sciences》2007,80(8):782-787
Epidemiological studies suggest that intrauterine undernutrition plays an important role in the development of arterial hypertension and endothelial dysfunction in adulthood. We have evaluated the effect of the Renin Angiotensin System inhibition on the blood pressure and the mesenteric arteriolar reactivity of the intrauterine undernourished rats. Wistar rats were fed either normal or 50% of the normal intake diets, during the whole gestational period. In this study only the male offspring was used. At 16 weeks of age, the rats were used for the study of blood pressure, microvascular reactivity studied in vivo-in situ to Angiotensin II (Ang II), Bradykinin (Bk) and Acetylcholine (Ach) before and after either losartan (10 mg/kg/15 days) or enalapril (15 mg/kg/21 days) treatment. We also evaluated the mesenteric and plasmatic Angiotensin Converting Enzyme (ACE), renal function, lipid plasmatic content, and insulin and glucose metabolism. Intrauterine undernutrition induced hypertension and increased response of mesenteric arterioles to Ang II and decreased vasodilation to Bk and Ach. The treatments with losartan or enalapril normalized the blood pressure levels and significantly improved the arteriolar responses to Bk, Ach and reduced the response to Ang II. No differences have been detected to ACE activity, renal function, lipid content and insulin and glucose metabolism. This study shows for the first time that Renin Angiotensin System inhibitors can normalize the cardiovascular alterations induced by intrauterine undernutrition. 相似文献
872.
Fujisaki K Tanabe N Suzuki N Kawato T Takeichi O Tsuzukibashi O Makimura M Ito K Maeno M 《Life sciences》2007,80(14):1311-1318
873.
建立胎鼠肺泡II型上皮细胞(AECII)与肺成纤维细胞(LF)共培养模型,观察与LF共培养下AECII的生物学特性。倒置相差显微镜观察AECII形态和基本生长情况;RT-PCR和流式细胞术分别检测肺泡表面活性蛋白-C(SP-C)、水通道蛋白5(AQP5)mRNA及蛋白质表达;流式细胞术检测细胞周期及Ki67表达。结果显示,与LF共培养时,AECII能较好地保留其细胞形态,SP-CmRNA及其蛋白质表达明显增加,而AQP5mRNA及其蛋白质表达则明显减少;LF促进AECII增殖,使G2/M、S期细胞及表达Ki67 细胞的比率明显增多。结果提示,AECII与LF共培养时,能更好地保留其细胞形态、分化及增殖特性。 相似文献
874.
Oberholzer A John T Kohl B Gust T Müller RD La Face D Hutchins B Zreiqat H Ertel W Schulze-Tanzil G 《Cell and tissue research》2007,328(2):383-390
Gene transfer into cultured chondrocytes by using adenoviral vectors has potential applications in treating cartilage disorders.
The present study was undertaken to compare and optimize two chondrocyte culture conditions for adenoviral transduction efficacy
by using primary human articular chondrocytes cultivated either directly in a monolayer condition or as outgrowths from alginate-stored
chondrocyte cultures. Isolated primary chondrocytes from human articular cartilage were either immediately transduced with
an EGFP (enhanced green fluorescent protein)-gene-bearing adenoviral vector (1,000 and 3,000 virus particles/cell) or cultured
in alginate before transduction. Immunohistochemistry and flow cytometric analysis were employed to determine the expression
of extracellular matrix proteins and of the αvβ5 integrin receptor involved in adenoviral cell entry. Monolayer chondrocytes
exhibited moderate transduction rates (mean 22.2% and 46.9% EGFP-positive cells at 1,000 and 3,000 virus particles/cell by
72 h post-transduction), whereas alginate-derived chondrocytes revealed significantly higher transduction efficacies (95.7%
and 99%). Both monolayer and alginate-derived chondrocytes expressed αvβ5 integrin, type II collagen and cartilage proteoglycans.
The mean fluorescence intensity of type II collagen was significantly higher in the alginate-derived chondrocytes, whereas
that of αvβ5 integrin was higher in the monolayer chondrocytes. Our results indicate that transduction efficacy is independent
of αvβ5 integrin expression levels in chondrocytes. Moreover, adenoviral transduction of alginate-derived chondrocytes is
more efficient than that for monolayer chondrocytes and may be a suitable tool to achieve sufficient numbers of transduced
and differentiated chondrocytes for experimental applications and cartilage repair.
Dr. Gundula Schulze-Tanzil is supported by a grant awarded by the Rahel Hirsh Foundation from the Charité Medical Schools
Berlin. The study was supported by a grant from the Deutsche Arthrosehilfe e.V. 相似文献
875.
Dalal A. Al-Mutairi James D. Craik Ines Batinic-Haberle Ludmil T. Benov 《Biochimica et Biophysica Acta (BBA)/General Subjects》2007
Cell proliferation is notably dependent on energy supply and generation of reducing equivalents in the form of NADPH for reductive biosynthesis. Blockage of pathways generating energy and reducing equivalents has proved successful for cancer treatment. We have previously reported that isomeric Zn(II) N-methylpyridylporphyrins (ZnTM-2(3,4)-PyP4+) can act as photosensitizers, preventing cell proliferation and causing cell death in vitro. The present study demonstrates that upon illumination, ZnTM-3-PyP inactivates glucose-6-phosphate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, lactate dehydrogenase, NADP+ -linked isocitrate dehydrogenase, aconitase, and fumarase in adenocarcinoma LS174T cells. ZnTM-3-PyP4+ was significantly more effective than hematoporphyrin derivative (HpD) for inactivation of all enzymes, except aconitase and isocitrate dehydrogenase. Enzyme inactivation was accompanied by aggregation, presumably due to protein cross-linking of some of the enzymes tested. Inactivation of metabolic enzymes caused disruption of cancer cells' metabolism and is likely to be one of the major reasons for antiproliferative activity of ZnTM-3-PyP. 相似文献
876.
877.
The functional state of the Photosystem (PS) II complex in Arabidopsis psbR T-DNA insertion mutant was studied. The ΔPsbR thylakoids showed about 34% less oxygen evolution than WT, which correlates with the amounts of PSII estimated from YDox radical EPR signal. The increased time constant of the slow phase of flash fluorescence (FF)-relaxation and upshift in the peak position of the main TL-bands, both in the presence and in the absence of DCMU, confirmed that the S2QA− and S2QB− charge recombinations were stabilized in ΔPsbR thylakoids. Furthermore, the higher amount of dark oxidized Cyt-b559 and the increased proportion of fluorescence, which did not decay during the 100s time span of the measurement thus indicating higher amount of YD+QA− recombination, pointed to the donor side modifications in ΔPsbR. EPR measurements revealed that S1-to-S2-transition and S2-state multiline signal were not affected by mutation. The fast phase of the FF-relaxation in the absence of DCMU was significantly slowed down with concomitant decrease in the relative amplitude of this phase, indicating a modification in QA to QB electron transfer in ΔPsbR thylakoids. It is concluded that the lack of the PsbR protein modifies both the donor and the acceptor side of the PSII complex. 相似文献
878.
Zdenko Gardian Ladislav Bumba Adam Schrofel Jana Nebesarova Frantisek Vacha 《BBA》2007,1767(6):725-731
Structure and organisation of Photosystem I and Photosystem II isolated from red alga Cyanidium caldarium was determined by electron microscopy and single particle image analysis. The overall structure of Photosystem II was found to be similar to that known from cyanobacteria. The location of additional 20 kDa (PsbQ′) extrinsic protein that forms part of the oxygen evolving complex was suggested to be in the vicinity of cytochrome c-550 (PsbV) and the 12 kDa (PsbU) protein. Photosystem I was determined as a monomeric unit consisting of PsaA/B core complex with varying amounts of antenna subunits attached. The number of these subunits was seen to be dependent on the light conditions used during cell cultivation. The role of PsaH and PsaG proteins of Photosystem I in trimerisation and antennae complexes binding is discussed. 相似文献
879.
The hypothesis presented here for proton transfer away from the water oxidation complex of Photosystem II (PSII) is supported by biochemical experiments on the isolated PsbO protein in solution, theoretical analyses of better understood proton transfer systems like bacteriorhodopsin and cytochrome oxidase, and the recently published 3D structure of PS II (Pdb entry 1S5L). We propose that a cluster of conserved glutamic and aspartic acid residues in the PsbO protein acts as a buffering network providing efficient acceptors of protons derived from substrate water molecules. The charge delocalization of the cluster ensures readiness to promptly accept the protons liberated from substrate water. Therefore protons generated at the catalytic centre of PSII need not be released into the thylakoid lumen as generally thought. The cluster is the beginning of a localized, fast proton transfer conduit on the lumenal side of the thylakoid membrane. Proton-dependent conformational changes of PsbO may play a role in the regulation of both supply of substrate water to the water oxidizing complex and the resultant proton transfer. 相似文献
880.