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101.
Catanesi CI Martina PF Giovambattista G Zukas P Vidal-Rioja L 《Human biology; an international record of research》2007,79(4):463-474
We investigated the genetic differentiation of five X-chromosome STR markers among five native South American Amerindian populations inhabiting three different areas of the Gran Chaco: Mocoví, Chorote, Wichí, Lengua, and Ayoreo. The observed genetic structure showed correspondence with geographic distribution more clearly than previous information obtained from autosomal STRs for the same samples. On the other hand, X-chromosome STR data did not agree with linguistic affinities. These markers proved to be informative for the study of the native populations of the Gran Chaco region. 相似文献
102.
103.
Flores N Leal L Sigala JC de Anda R Escalante A Martínez A Ramírez OT Gosset G Bolivar F 《Journal of molecular microbiology and biotechnology》2007,13(1-3):105-116
In Escherichia coli the phosphotransferase system (PTS) consumes one molecule of phosphoenolpyruvate (PEP) to phosphorylate each molecule of internalized glucose. PEP bioavailability into the aromatic pathway can be increased by inactivating the PTS. However, the lack of the PTS results in decreased glucose transport and growth rates. To overcome such drawbacks in a PTS(-) strain and reconstitute rapid growth on glucose phenotype (Glc(+)), the glk and galP genes were cloned into a plasmid and the arcA gene was inactivated. Simultaneous overexpression of glk and galP increased the growth rate and regenerated a Glc(+) phenotype. However, the highest growth rate was obtained when glk and galP were overexpressed in the arcA(-) background. These results indicated that the arcA mutation enhanced glycolytic and respiratory capacities of the engineered strain. 相似文献
104.
105.
Effects of litter traits,soil biota,and soil chemistry on soil carbon stocks at a common garden with 14 tree species 总被引:1,自引:0,他引:1
Kevin E. Mueller Sarah E. Hobbie Jon Chorover Peter B. Reich Nico Eisenhauer Michael J. Castellano Oliver A. Chadwick Tomasz Dobies Cynthia M. Hale Andrzej M. Jagodziński Izabela Kałucka Barbara Kieliszewska-Rokicka Jerzy Modrzyński Anna Rożen Maciej Skorupski Łukasz Sobczyk Małgorzata Stasińska Lidia K. Trocha January Weiner Anna Wierzbicka Jacek Oleksyn 《Biogeochemistry》2015,123(3):313-327
106.
107.
Agata Jacewicz Lidia Chico Paul Smith Beate Schwer Stewart Shuman 《RNA (New York, N.Y.)》2015,21(3):401-414
Saccharomyces cerevisiae Msl5 orchestrates spliceosome assembly by binding the intron branchpoint sequence 5′-UACUAAC and, with its heterodimer partner protein Mud2, establishing cross intron-bridging interactions with the U1 snRNP at the 5′ splice site. Here we define the central Msl5 KH-QUA2 domain as sufficient for branchpoint RNA recognition. The 1.8 Å crystal structure of Msl5-(KH-QUA2) bound to the branchpoint highlights an extensive network of direct and water-mediated protein–RNA and intra-RNA atomic contacts at the interface that illuminate how Msl5 recognizes each nucleobase of the UACUAAC element. The Msl5 structure rationalizes a large body of mutational data and inspires new functional studies herein, which reveal how perturbations of the Msl5·RNA interface impede the splicing of specific yeast pre-mRNAs. We also identify interfacial mutations in Msl5 that bypass the essentiality of Sub2, a DExD-box ATPase implicated in displacing Msl5 from the branchpoint in exchange for the U2 snRNP. These studies establish an atomic resolution framework for understanding splice site selection and early spliceosome dynamics. 相似文献
108.
109.
Excessive consumption of highly palatable food has been linked to the development of eating disorders and obesity, and can
be modeled in non-food-deprived rats by offering them a limited (2-h daily) access to an optional dietary fat. Since the glutamatergic
system has recently emerged as a viable target for binge-eating medication development, we compared the effects of subchronic
treatment with glutamatergic receptor antagonists to the effects of a reference appetite-suppressing agent sibutramine on
highly palatable food (lard) and normal chow intake. In three separate experiments, the consumption of a standard laboratory
chow and lard were measured during 12 days of medication treatment and for 6 days afterwards. Generalized estimating equations
analysis demonstrated that sibutramine (7.5 mg/kg, PO) significantly decreased lard consumption, with a concurrent increase
in chow consumption. Sibutramine effects disappeared after treatment discontinuation. The NMDA receptor antagonist memantine
(5 mg/kg, IP) significantly decreased lard consumption and increased chow consumption, comparable to effects of sibutramine;
however, memantine’s effects persisted after treatment discontinuation. The effects of the mGluR5 antagonist MTEP (7.5 mg/kg,
IP) on food consumption were in the same direction as seen with memantine, but the observed differences were not significant.
In an additional control experiment, sibutramine and memantine reduced unlimited (24 h) chow intake during the treatment phase.
Present results provide evidence that glutamatergic neurotransmission might be involved in the regulation of excessive consumption
of highly palatable foods, and suggest that NMDA receptor may be an attractive target for developing obesity and disordered
eating pharmacotherapies. 相似文献
110.
Transforming growth factor β (TGF-β) is a very strong pro-fibrotic factor which mediates its action, at least in part, through the expression of connective tissue growth factor (CTGF/CCN2). Along with these cytokines, the involvement of phospholipids in wound healing and the development of fibrosis has been revealed. Among them, lysophosphatidic acid (LPA) is a novel, potent regulator of wound healing and fibrosis that has diverse effects on many types of cells. We decided to evaluate the effect of LPA together with TGF-β on CTGF expression. We found that myoblasts treated with LPA and TGF-β1 produced an additive effect on CTGF expression. In the absence of TGF-β, the induction of CTGF expression by LPA was abolished by a dominant negative form of the TGF-β receptor type II (TGF-βRII) and by the use of SB 431542, a specific inhibitor of the serine/threonine kinase activity of TGF-βRI, suggesting that CTGF induction is dependent on LPA and requires active TGF-βRs. Moreover, we show that LPA requires Smad-2/3 proteins for the induction of CTGF expression, but not their phosphorylation or their nuclear translocation. The requirement of TGF-βRI for LPA mediated-effects is differential, since treatment of myoblasts with LPA in the presence of SB 431542 abolished the induction of stress fibers but not the induction of proliferation. Finally, we demonstrated that CTGF induction in response to LPA requires the activation of JNK, but not ERK, signaling pathways. The JNK requirement is independent of TGF-βRI-mediated activity. These novel results for the mechanism of action of LPA and TGF-β are important for understanding the role of pro-fibrotic growth factors and phospholipids involved in wound healing and related diseases. 相似文献