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71.
Corticotropin-releasing factor (CRF) is involved in a variety of physiological functions including regulation of hypothalamo-pituitary-adrenal axis activity during stressful periods. Urocortins (Ucns) are known to be members of the CRF family peptides. CRF has a high affinity for CRF receptor type 1 (CRF(1) receptor). Both Ucn2 and Ucn3 have very high affinity for CRF receptor type 2 (CRF(2) receptor) with little or no binding affinity for the CRF(1) receptor. Gonadotropin-releasing hormone (GnRH) is known to be involved in the regulation of the stress response. Gonadotropin-inhibitory hormone (GnIH) neurons interact directly with GnRH neurons, and the action of GnIH is mediated by a novel G-protein coupled receptor, Gpr147. This study aimed to explore the possible function of CRF family peptides and the regulation of GnRH mRNA in hypothalamic GnRH cells. Both mRNA and protein expression of the CRF(1) receptor and CRF(2) receptor were found in hypothalamic GnRH N39 cells. CRF suppressed GnRH mRNA levels via the CRF(1) receptor, while Ucn2 increased the levels via the CRF(2) receptor. Both CRF and Ucn2 increased Gpr147 mRNA levels. The results indicate that CRF and Ucn2 can modulate GnRH mRNA levels via each specific CRF receptor subtype. Finally, CRF suppressed GnRH protein levels, while Ucn2 increased the levels. Differential regulation of GnRH by CRF family peptides may contribute to the stress response and homeostasis in GnRH cells. 相似文献
72.
Yamazaki S Iwamoto R Saeki K Asakura M Takashima S Yamazaki A Kimura R Mizushima H Moribe H Higashiyama S Endoh M Kaneda Y Takagi S Itami S Takeda N Yamada G Mekada E 《The Journal of cell biology》2003,163(3):469-475
Heparin-binding EGF-like growth factor (HB-EGF) is first synthesized as a membrane-anchored form (proHB-EGF), and its soluble form (sHB-EGF) is released by ectodomain shedding from proHB-EGF. To examine the significance of proHB-EGF processing in vivo, we generated mutant mice by targeted gene replacement, expressing either an uncleavable form (HBuc) or a transmembrane domain-truncated form (HBdeltatm) of the molecule. HB(uc/uc) mice developed severe heart failure and enlarged heart valves, phenotypes similar to those in proHB-EGF null mice. On the other hand, mice carrying HBdeltatm exhibited severe hyperplasia in both skin and heart. These results indicate that ectodomain shedding of proHB-EGF is essential for HB-EGF function in vivo, and that this process requires strict control. 相似文献
73.
A recurrent mutation in type II collagen gene causes Legg-Calvé-Perthes disease in a Japanese family
Miyamoto Y Matsuda T Kitoh H Haga N Ohashi H Nishimura G Ikegawa S 《Human genetics》2007,121(5):625-629
Legg-Calvé-Perthes disease (LCPD) is a common childhood hip disorder characterized by sequential stages of involvement of
the capital femoral epiphyses, including subchondral fracture, fragmentation, re-ossification and healing with residual deformity.
Most cases are sporadic, but familial cases have been described, with some families having multiple affected members. Genetic
factors have been implicated in the etiology of LCPD, but the causal gene has not been identified. We have located a missense
mutation (p.G1170S) in the type II collagen gene (COL2A1) in a Japanese family with an autosomal dominant hip disorder manifesting as LCPD and showing considerable intra-familial
phenotypic variation. This is the first report of a mutation in hereditary LCPD. COL2A1 mutations may be more common in LCPD patients than currently thought, particularly in familial and/or bilateral cases. 相似文献
74.
Comparative study of the edema-forming activity of Costa Rican snake venoms and its neutralization by a polyvalent antivenom 总被引:3,自引:0,他引:3
J M Gutiérrez G Rojas B Lomonte J A Gené L Cerdas 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1986,85(1):171-175
The edema-forming activity of eight Costa Rican crotaline snake venoms and its neutralization by a polyvalent antivenom were studied using the mouse footpad test. All of the venoms induced edema, the highest activity being present in the venoms of Bothrops lateralis and Bothrops picadoi. When experiments were performed with preincubation of venom and antivenom, neutralization of edema was poor. Moreover, it was observed that, with some venoms, edema increased when large doses of antivenom were used. This effect was also observed when some venoms were incubated with coral snake antivenom, suggesting that venoms may release some pharmacologically active component(s) from antivenom, since the latter contains traces of alpha-2 and beta globulins. Based on these findings, an alternative approach to the study of the neutralization of edema was used; in this new method, antivenom was injected i.v. before venom administration, thereby avoiding preincubation. With this technique, a much better neutralization of edema was observed, although with some venoms it was still poor. Venoms contain low molecular weight factors which induce edema, suggesting that lack of immunogenicity of some components may cause a poor neutralization. However, such components are responsible for only a minor portion of the edema induced by crude venoms. It is suggested that experiments in which venom and antivenom are preincubated preincubated in testing the neutralization of edema should be avoided, and that a more adequate approach may be an independent inoculation of venom and antivenom. 相似文献
75.
三唑酮对黄瓜子叶抗氧化酶活力的影响 总被引:4,自引:2,他引:4
黄瓜子叶衰老过程中超氧物歧化酶(SOD)、过氧化氢酶(CAT)和抗坏血酸-过氧化物酶(ASA-POD)活性降低,而过氧化物酶(POD)活性升高。20mg/L三唑酮右明显提高SOD,ASA-POD,CAT活性,抑制POD活性升高。膜脂过氧化产物丙二醛(MDA)含量在叶片衰老过程中提高,三唑酮可降低MDA含量。表明三唑酮减轻脂氧化程度,延缓了叶片的衰老。 相似文献
76.
Jun Hong Xia Grace Lin Xiaoping He Bu Yunping Peng Liu Feng Liu Fei Sun Rongjian Tu Gen Hua Yue 《Marine biotechnology (New York, N.Y.)》2014,16(1):1-9
Omega-3 fatty acids are essential fatty acids for human health. Therefore, increasing both percentage of omega-3 and a better fatty acid profile in fish fillets is one of the breeding goals in aquaculture. However, it is difficult to increase the omega-3 content in fish fillets, as the phenotypic selection of these traits is not easily feasible. To facilitate the genetic improvement of the Asian seabass for optimal fatty acid profiles, a genome-wide scan for quantitative trait loci (QTL) affecting fatty acid level in the flesh of the Asian seabass was performed on an F2 family containing 314 offspring. All family members were genotyped using 123 informative microsatellites and 22 SNPs. High percentages of n-3 polyunsaturated fatty acids (PUFA), especially C22:6 (DHA 16.48?±?3.09 %) and C20:5 (EPA 7.19?±?0.86 %) were detected in the flesh. One significant and 54 suggestive QTL for different fatty acids and a water content trait were detected on the whole genome. QTL for C18:0b was located on linkage groups (LG) 5. QTL for total n-3 PUFA content in flesh were mapped onto LG6 and LG23 with the phenotypic variance explained ranging from 3.8 to 6.3 %. Four QTL for C22:6 were detected on LG6, LG23, and LG24, explaining 3.9 to 4.9 % of the phenotypic variance, respectively. Mapping of QTL for contents of different fatty acids is the first step towards improving the omega-3 content in the fillets of fish by using marker-assisted selection and is important for understanding the biology of fatty acid deposition. 相似文献
77.
Identification of a new 84/82 kDa calmodulin-binding protein, which also interacts with actin filaments, tubulin and spectrin, as synapsin I 总被引:4,自引:0,他引:4
A new 84/82 kDa calmodulin-binding protein, which also interacts with actin filaments, tubulin and spectrin, was purified from the bovine synaptosomal membrane. The binding of calmodulin to this protein was Ca2+-dependent, and was inhibited by trifluoperazine, the association constant being calculated to be 2.2 X 10(6) M-1. Maximally, 1 mol of calmodulin bound to 1 mol of the purified protein. This protein was phosphorylated by both kinase II (Ca2+- and calmodulin-dependent kinase) and cyclic AMP-dependent kinase. In addition, antibody against this protein was demonstrated to have an immunological crossreactivity with synapsin I in the synaptosomal membrane. 相似文献
78.
Chen Y Rao F Wen G Gayen JR Zhang K Vaingankar SM Biswas N Mahata M Friese RS Fung MM Salem RM Nievergelt C Bhatnagar V Hook VY Ziegler MG Mahata SK Hamilton BA O'Connor DT 《Cellular and molecular neurobiology》2010,30(8):1395-1400
Chromogranin A (CHGA) plays a fundamental role in the biogenesis of catecholamine secretory granules. Changes in storage and release of CHGA in clinical and experimental hypertension prompted us to study whether genetic variation at the CHGA locus might contribute to alterations in autonomic function, and hence hypertension and its target organ consequences such as hypertensive renal disease (nephrosclerosis). Systematic polymorphism discovery across the human CHGA locus revealed both common and unusual variants in both the open reading frame and such regulatory regions as the proximal promoter and 30-UTR. In chromaffin cell-transfected CHGA 30-UTR and promoter/luciferase reporter plasmids, the functional consequences of the regulatory/non-coding allelic variants were documented. Variants in both the proximal promoter and the 30-UTR displayed statistical associations with hypertension. Genetic variation in the proximal CHGA promoter predicted glomerular filtration rate in healthy twins. However, for hypertensive renal damage, both end-stage renal disease and rate of progression of earlier disease were best predicted by variants in the 30-UTR. Finally, mechanistic studies were undertaken initiated by the clue that CHGA promoter variation predicted circulating endothelin-1. In cultured endothelial cells, CHGA triggered co-release of not only the vasoconstrictor and pro-fibrotic endothelin-1, but also the pro-coagulant von Willebrand Factor and the pro-angiogenic angiopoietin-2. These findings, coupled with stimulation of endothelin-1 release from glomerular capillary endothelial cells by CHGA, suggest a plausible mechanism whereby genetic variation at the CHGA locus eventuates in alterations in human renal function. These results document the consequences of genetic variation at the CHGA locus for cardiorenal disease and suggest mechanisms whereby such variation achieves functional effects. 相似文献
79.
80.
Hui Mao Gen Kano Sherry A. Hudson Mary Brummet Nives Zimmermann Zhou Zhu Bruce S. Bochner 《PloS one》2013,8(6)