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991.
992.
Mammalian TOR complex 2 controls the actin cytoskeleton and is rapamycin insensitive 总被引:16,自引:0,他引:16
Jacinto E Loewith R Schmidt A Lin S Rüegg MA Hall A Hall MN 《Nature cell biology》2004,6(11):1122-1128
The target of rapamycin (TOR) is a highly conserved protein kinase and a central controller of cell growth. In budding yeast, TOR is found in structurally and functionally distinct protein complexes: TORC1 and TORC2. A mammalian counterpart of TORC1 (mTORC1) has been described, but it is not known whether TORC2 is conserved in mammals. Here, we report that a mammalian counterpart of TORC2 (mTORC2) also exists. mTORC2 contains mTOR, mLST8 and mAVO3, but not raptor. Like yeast TORC2, mTORC2 is rapamycin insensitive and seems to function upstream of Rho GTPases to regulate the actin cytoskeleton. mTORC2 is not upstream of the mTORC1 effector S6K. Thus, two distinct TOR complexes constitute a primordial signalling network conserved in eukaryotic evolution to control the fundamental process of cell growth. 相似文献
993.
Plants: the latest model system for G-protein research 总被引:11,自引:0,他引:11
In humans, heterotrimeric G proteins couple stimulus perception by G-protein-coupled receptors (GPCRs) with numerous downstream effectors. By contrast, despite great complexity in their signal-transduction attributes, plants have a simpler repertoire of G-signalling components. Nonetheless, recent studies on Arabidopsis thaliana have shown the importance of plant G-protein signalling in such fundamental processes as cell proliferation, hormone perception and ion-channel regulation. 相似文献
994.
Comparing gene discovery from Affymetrix GeneChip microarrays and Clontech PCR-select cDNA subtraction: a case study 总被引:1,自引:0,他引:1
995.
Verjovski-Almeida S Leite LC Dias-Neto E Menck CF Wilson RA 《Trends in parasitology》2004,20(7):304-308
996.
Background
Site-directed mutagenesis is an efficient method to alter the structure and function of genes. Here we report a rapid and efficient megaprimer-based polymerase chain reaction (PCR) mutagenesis strategy that by-passes any intermediate purification of DNA between two rounds of PCR. 相似文献997.
Lai CM Yu MJ Brankov M Barnett NL Zhou X Redmond TM Narfstrom K Rakoczy PE 《Genetic vaccines and therapy》2004,2(1):3
Background
Leber's congenital amaurosis (LCA) is a severe form of retinal dystrophy. Mutations in the RPE65 gene, which is abundantly expressed in retinal pigment epithelial (RPE) cells, account for approximately 10–15% of LCA cases. In this study we used the high turnover, and rapid breeding and maturation time of the Rpe65 -/- knockout mice to assess the efficacy of using rAAV-mediated gene therapy to replace the disrupted RPE65 gene. The potential for rAAV-mediated gene treatment of LCA was then analyzed by determining the pattern of RPE65 expression, the physiological and histological effects that it produced, and any improvement in visual function. 相似文献998.
Treatment options for stress urinary incontinence (SUI) in women are designed to prevent the involuntary loss of urine from the urethra during increases in intraabdominal pressure that occur during physical activity, coughing, or sneezing. Effective nonsurgical therapies include behavioral therapy (eg, bladder training, fluid and dietary modification) and drug therapy. Surgical therapy for this condition has existed for well over 100 years. Currently, approximately 200 different surgical procedures have been described. Because of the physiologic risks inherent in surgical procedures, the cost of hospitalization, and the loss of productivity during convalescence, surgeons continue to modify their techniques to improve efficacy, safety, and cost-effectiveness, and to minimize invasiveness. No single procedure or intervention is optimal for all patients. Having a variety of treatment options offers the possibility of tailoring therapy to the desires and needs of the individual patient. The key to an optimal therapeutic outcome is an accurate diagnosis combined with the selection of an appropriate intervention that is acceptable to the patient after balancing multiple factors. 相似文献
999.
1000.
Cady FM Muto DN Ciabeterri G Johns A Gainey Church K Wolff DJ 《Journal of the Association of Genetic Technologists》2004,30(3):77-81
Specific genetic abnormalities are of prognostic significance for patients with chronic lymphocytic leukemia (CLL) and multiple myeloma (MM); however, routine cytogenetic analysis usually provides normal results. We utilized two probe panels for interphase fluorescence in situ hybridization (FISH) studies to enhance the ability to detect genetic abnormalities in samples that were referred for routine cytogenetic studies for possible diagnoses of CLL or MM. The CLL panel consisted of probes for 11q22.3 (ATM gene), 13q14 (D13S319), the centromere of chromosome 12 (D12Z3) and 17p13.1 (P53 gene). The MM panel included probes for 14q32 (IgH gene) and/or t(11:14)(q13;q32) (BCL1/IgH), 13q14 (D13S319) and 17p13.1 (P53 gene). FISH detected clonal aberrations not identified by conventional cytogenetics in an additional 8 of 23 (35%) samples referred for possible CLL and 7 of 42 (17%) samples with possible MM. The prognostic significance of the aberrations identified ranged from favorable, to intermediate, to poor. Our studies indicate that many samples referred for routine cytogenetics testing for CLL and MM yield normal results for both conventional and FISH testing, likely due to lack of definitive diagnosis in a percentage of cases. However, FISH is more sensitive for the detection of clinically significant chromosome abnormalities and should be the testing methodology of choice for these disorders. 相似文献