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91.
Recently, a genome‐wide association study (GWAS) that identified eight single‐nucleotide polymorphisms (SNPs) associated with BMI highlighted a possible neuronal influence on the development of obesity. We hypothesized these SNPs would govern the response of BMI and subcutaneous fat to resistance training in young individuals (age = 24 years). We genotyped the eight GWAS‐identified SNPs in the article by Willer et al. in a cohort (n = 796) that undertook a 12‐week resistance‐training program. Females with a copy of the rare allele (C) for rs17782313 (MC4R) had significantly higher BMIs (CC/CT: n = 174; 24.70 ± 0.33 kg/m2, TT: n = 278; 23.41 ± 0.26 kg/m2, P = 0.002), and the SNP explained 1.9% of overall variation in BMI. Males with a copy of the rare allele (T) for rs6548238 (TMEM18) had lower amounts of subcutaneous fat pretraining (CT/TT: n = 65; 156,534 ± 7,415 mm3, CC: n = 136; 177,825 ± 5,139 mm3, P = 0.019) and males with a copy of the rare allele (A) for rs9939609 (FTO) lost a significant amount of subcutaneous fat with exercise (AT/AA: n = 83; ?798.35 ± 2,624.30 mm3, TT: n = 47; 9,435.23 ± 3,494.44 mm3, P = 0.021). Females with a copy of the G allele for a missense variant in the SH2B1 (rs7498665) was associated with less change of subcutaneous fat volume with exercise (AG/GG: n = 191; 9,813 ± 2,250 mm3 vs. AA: n = 126; 770 ± 2,772 mm3; P = 0.011). These data support the original finding that there is an association between measures of obesity and a variant near the MC4R gene and extends these results to a younger population and implicates FTO, TMEM18, and SH2B1 polymorphisms in subcutaneous fat regulation.  相似文献   
92.
Desulfovibrio alaskensis G20 (formerly Desulfovibrio desulfuricans G20) is a Gram-negative mesophilic sulfate-reducing bacterium (SRB), known to corrode ferrous metals and to reduce toxic radionuclides and metals such as uranium and chromium to sparingly soluble and less toxic forms. We present the 3.7-Mb genome sequence to provide insights into its physiology.  相似文献   
93.
In the course of recent efforts to identify new potential antiproliferative active principles, Salvia leriifolia extracts and isolated constituents were evaluated for their cytotoxic activity against a panel of human cancer cell lines, including renal adenocarcinoma (ACHN), amelanotic melanoma (C32), colorectal adenocarcinoma (Caco‐2), lung large cell carcinoma (COR‐L23), malignant melanoma (A375), lung carcinoma (A549), and hepatocellular carcinoma (Huh‐7D12) cells. The hexane and CH2Cl2 extracts showed the strongest cytotoxic activity against the C32 cell line with IC50 values of 11.2 and 13.6 μg/ml, respectively, and the AcOEt extract was the most active extract against the COR‐L23 cell line (IC50 of 20.9 μg/ml). Buchariol, a sesquiterpene obtained by biofractionation of the CH2Cl2 extract, exhibited a higher activity than the positive control vinblastine against the C32 and A549 cell lines (IC50 values of 2.1 and 12.6 μM , resp.). Interesting results were also obtained for naringenin, a flavonoid isolated from the AcOEt extract, which exhibited a strong cytotoxic activity against the C32, LNCaP, and COR‐L23 cell lines (IC50 values of 2.2, 7.7, and 33.4 μM , resp.), compared to vinblastine (IC50 values of 3.3, 32.2, 50.0 μM , resp.). None of the tested compounds affected the proliferation of skin fibroblasts (142BR), suggesting a selective activity against tumor cells.  相似文献   
94.
We have developed an efficient, reproducible, and scaleable cell culture process for a recombinant adenoviral vector expressing therapeutic transgenes for clinical trials. HEK 293 cells – which support the propagation of E1 deficient adenovirus – were first adapted to serum free media and suspension growth. Subsequent studies focused on the infection, virus production and harvest from suspension culture bioreactors. Future studies are planned to address the kinetics of adenovirus production in HEK 293 as well as in other cell lines. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
95.
The present purpose was to examine how sleep deprivation affects the estrous cycle of the female rat. Paradoxical sleep-deprived (PSD) adult female Wistar rats were compared to home-cage control (CTRL) on their estrous cyclicity. Forty-four PSD and forty-four CTRL female rats were distributed into 4 subgroups of 11 animals each according to the phase of estrous cycle and were subjected to sleep deprivation for 96 h by the multiple platform technique. After PSD period, vaginal estrous cycles were taken for an additional 9 days. Animals that were submitted to PSD in diestrus phase (PSD-diestrus) had their estrous cycles disrupted during the recovery period by showing a constant diestrus during the first week. As for hormone alterations, progesterone concentrations were statistically higher in PSD-diestrus compared to respective phase control and to PSD-proestrus and PSD-estrus rats while CTRL-metestrus had higher levels than CTRL-proestrus and estrus groups. Testosterone was significantly decreased in PSD-estrus in relation to PSD-proestrus and PSD-diestrus groups and was lower in CTRL-diestrus rats than in home-cage rats in proestrus. In addition, PSD-diestrus phase exhibited higher concentrations of corticosterone and lower estrogen than the respective control rats. These data indicate that PSD may modulate the ovarian hormone release through alterations in hormonal-neurochemical mechanisms.  相似文献   
96.
97.
Biosynthetically, bovine N-acetylglucosainine ß 1,4-galacto-syltransferase(GalT) catalyses the transfer of galactosyl residues from UDP-Galto the 4-position of GlcNAc units, resulting in the productionof N-acetyllactosamine sequences. UDP-Glc and UDP-GalNAc werealso found to act as donors for this enzyme, allowing the preparationof ßGlc(14)-ßGlcNAc and ßGalNAc(14)ßGlcNActerminating structures on the milligram scale. GalT could thusbe used to add ßGalNAc to ßGlcNAc(12)Manterminating structures, converting them to the ßGalNAc(14)ßGlcNAc(12)Mansequences found on glycoprotein hormones. GalT did not transferGlcNAc residues from UDP-GlcNAc, but it could utilize UDP-GlcNH2as a donor. Synthesis of ßGlcNAc(14)ßGlcNAcsequences could therefore be accomplished by transfer of GlcNH2from its UDP derivative, followed by N-acetylation of the productamino-disaccharide using acetic anhydride in methanol. The productsof the enzymatic reactions were characterized by 1H-NMR-spectroscopyand fast-atom bombardment mass spectrometry. This work expandsthe scope of the combined chemical-enzymatic synthesis of complexcarbohydrates, using glycosyltrans-ferases, to the productionof oligosaccharides different from those for which these enzymeswere designed. These unnatural reactions should find applicationin glycoprotein and glycolipid remodelling. galactosyltransferase chemica1-enzymatic synthesis of oligosaccharides oligosaccharide analogues sugar-nucleotide analogues carbohydrate remodelling  相似文献   
98.
For nearly 40 years functional studies of the mouse quaking gene (qkI) have focused on its role in the postnatal central nervous system during myelination. However, the homozygous lethality of a number of ENU-induced alleles reveals that quaking has a critical role in embryonic development prior to the start of myelination. In this article, we show that quaking has a previously unsuspected and essential role in blood vessel development. Interestingly, we found that quaking, a nonsecreted protein, is expressed in the yolk sac endoderm, adjacent to the mesodermal site of developing blood islands, where the differentiation of blood and endothelial cells first occurs. Antibodies against PE-CAM-1, TIE-2 and SM-alpha-actin reveal that embryos homozygous for the qk(k2) allele have defective yolk sac vascular remodeling and abnormal vessels in the embryo proper at midgestation, coinciding with the timing of embryonic death. However, these mutants exhibit normal expression of Nkx2.5 and alpha-sarcomeric actin, indicating that cardiac muscle differentiation was normal. Further, they had normal embryonic heart rates in culture, suggesting that cardiac function was not compromised at this stage of embryonic development. Together, these results suggest that quaking plays an essential role in vascular development and that the blood vessel defects are the cause of embryonic death.  相似文献   
99.
BACKGROUND AIMS. Previously, cytotoxic T lymphocyte antigen 4 (CTLA4) immunoglobulin (Ig) has been shown to allow sustained engraftment in dog leukocyte antigen (DLA)-identical hematopoietic cell transplant (HCT) after non-myeloablative conditioning with 100 cGy total body irradiation (TBI). In the current study, we investigated the efficacy of pre-transplant CTLA4-Ig in promoting engraftment across a DLA-mismatched barrier after non-myeloablative conditioning. METHODS. Eight dogs were treated with CTLA4-Ig and donor peripheral blood mononuclear cells (PBMC) prior to receiving 200 cGy TBI followed by transplantation of granulocyte-colony-stimulating factor (G-CSF) mobilized peripheral blood stem cells from DLA haplo-identical littermates with post-grafting immunosuppression. A control group of six dogs was conditioned with 200 cGy only and transplanted with grafts from DLA haplo-identical littermates followed by post-grafting immunosuppression. RESULTS. In vitro and in vivo donor-specific hyporesponsiveness was demonstrated on day 0 before TBI in eight dogs that received CTLA4-Ig combined with donor PBMC infusions. Four of five dogs treated with increased doses of CTLA4-Ig achieved initial engraftment but eventually rejected, with a duration of mixed chimerism ranging from 12 to 22 weeks. CTLA4-Ig did not show any effect on host natural killer (NK) cell function in vitro or in vivo. No graft-versus-host disease (GvHD) was observed in dogs receiving CTLA4-Ig treatment. CONCLUSIONS. Non-myeloablative conditioning with 200 cGy TBI and CTLA4-Ig combined with donor PBMC infusion was able to overcome the T-cell barrier to achieve initial engraftment without GvHD in dogs receiving DLA haplo-identical grafts. However, rejection eventually occurred; we hypothesize because of the inability of CTLA4-Ig to abate natural killer cell function.  相似文献   
100.
Previous reports have demonstrated that systemic injection of cholecystokinin (CCK) in rats produces dose-related decreases in food intake, increases in neurohypophyseal secretion of oxytocin (OT), and decreases in gastric emptying. The present studies determined whether systemic injection of bombesin (BBS), another peptide that potently reduces food intake in rats, had similar effects on OT secretion and gastric emptying. Although BBS produces a dose-dependent inhibition of food intake, even very high doses did not significantly affect plasma OT levels and only slightly decreased rates of gastric emptying. Consequently, despite their similar inhibitory effects on food intake, BBS does not appear to activate the same network of central nervous system pathways as does CCK in rats. However, parallel studies in monkeys demonstrated that systemic injection of BBS was effective in stimulating neurohypophyseal secretion of vasopressin rather than OT, in a pattern both qualitatively and quantitatively analogous to the effects of CCK in this species. Together with previous findings that BBS more potently inhibits gastric emptying in primates than in rats, these results therefore also suggest the presence of significant species differences in the central mechanisms by which BBS acts to reduce food intake.  相似文献   
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