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941.
Married individuals tend to be heavier than those who are unmarried, particularly men, and individuals in different ethnic categories vary in their involvement in marriage and in their body weights. We examined gender and ethnic differences in relationships between marital status and body weight using cross‐sectional data from the 1999–2002 National Health and Nutrition Examination Survey (NHANES) for 3,947 women and 4,019 men. The findings revealed that compared to married men in the same ethnic category, white divorced men, black never‐married men, and all Hispanic men except for widows had lower odds of being overweight. Compared to married women in the same ethnic category, white women's weights did not significantly differ by marital status, black separated women had greater odds of being overweight, and Hispanic never‐married women had lower odds of being overweight. Associations of marriage with body weight appear to be at least partly contingent upon gender and ethnicity, which may reflect larger societal patterns of involvement in marriage, commitment to family, and body‐weight norms and expectations.  相似文献   
942.
Endothelial dysfunction may link obesity to cardiovascular disease (CVD). We tested the hypothesis that visceral abdominal tissue (VAT) as compared with subcutaneous adipose tissue (SAT) is more related to endothelium‐dependent vasodilation. Among Framingham Offspring and Third Generation cohorts (n = 3,020, mean age 50 years, 47% women), we used multivariable linear regression adjusted for CVD and its risk factors to relate computed tomography (CT)‐assessed VAT and SAT, BMI, and waist circumference (WC), with brachial artery measures. In multivariable‐adjusted models, BMI, WC, VAT, and SAT were positively related to baseline artery diameter and baseline mean flow velocity (all P < 0.001), but not hyperemic mean flow velocity. In multivariable‐adjusted models, BMI (P = 0.002), WC (P = 0.001), and VAT (P = 0.01), but not SAT (P = 0.24) were inversely associated with percentage of flow‐mediated dilation (FMD%). However, there was little incremental increase in the proportion of variability explained by VAT (R2 = 0.266) as compared to SAT (R2 = 0.265), above and beyond traditional risk factors. VAT, but not SAT was associated with FMD% after adjusting for clinical covariates. Nevertheless, the differential association with VAT as compared to SAT was minimal.  相似文献   
943.
A series of twenty-one 7-chloro-4-quinolinylhydrazones (3au) have been synthesized and evaluated for their in vitro antibacterial activity against Mycobacterium tuberculosis H37Rv. The compounds 3f, 3i and 3o were non-cytotoxic and exhibited an important minimum inhibitory concentration (MIC) activity (2.5 μg/mL), which can be compared with that of the first line drugs, ethambutol (3.12 μg/mL) and rifampicin (2.0 μg/mL). These results can be considered an important start point for the rational design of new leads for anti-TB compounds.  相似文献   
944.
A series of novel 1-aminocyclopentyl-3-carboxyamides incorporating substituted tetrahydropyran moieties have been synthesized and subsequently evaluated for their antagonistic activity against the human CCR2 receptor. Among them analog 59 was found to posses potent antagonistic activity.  相似文献   
945.
Gelatinization in excess of water and melting transition for different moisture contents of a ready-to-eat cereal formulation (RTE blend) and its major components, (i.e., oat flour, rice flour, and an oat–rice flour blend) were studied by differential scanning calorimetry (DSC) and rapid visco-analyzer (RVA). The highest swelling power was exhibited by the rice flour and the lowest by the RTE blend. Two endothermic peaks under excess of water were exhibited by all materials, at 53–75 °C and 80–102 °C, and they were associated to gelatinization and cereal protein denaturation, respectively. A third peak appearing in all materials except in rice flour, at higher temperatures (102–116 °C), was attributed to the melting of the amylose–lipid complexes. The effect of water in the melting of the flours and blends was well described by the Flory–Huggins equation and its parameters agreed well with those reported in the literature for starchy products. A theoretical value of the polymer–diluent (starch–water) interaction factor for starch of 0.36 was calculated from a combined model of Hildebrand empirical approach to solubility and the Flory–Huggins theory, and reasonably compared with the interaction parameter (χ) obtained for the materials considered in this work. State diagrams for the oat–rice flour blend and for the RTE blend going through an extrusion process were finally obtained.  相似文献   
946.
The effect of water content on the glass transition temperatures of cassava starch was determined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). Samples were transformed to the amorphous state by compression molding at high temperature (as demonstrated by wide angle X-ray diffraction, WAXS), and then the samples were moisture conditioned. Both DSC and DMTA showed that water anti-plasticized cassava starch at lower moisture contents, and plasticized it at higher water contents. Samples with higher moisture contents stored at room temperature, 45 °C and 80 °C underwent retrogradation as indicated by WAXS. Sorption isotherms of cassava starch showed that for aw values lower than around 0.85, the sorption capacity decreased with increasing temperature; while the opposite behavior was observed at aw > 0.85. This inversion point (aw = 0.85) was attributed to the fact that more active sites were exposed to the adsorption processes, due to the enhanced molecular mobility promoted in the amorphous regions by starch crystallization.  相似文献   
947.
An evaluation of the potential hazards associated with mutagenicity and acute toxicity of a mycoherbicide formulation based on the fungal pathogen Cercospora piaropi was performed. Neither the mycoherbicide nor any of its components were mutagenic to Salmonella typhimurium TA98 and TA100 with or without metabolic activation. Both the C. piaropi and the mycoherbicide formulation were shown to be moderately toxic with a bacterial bioluminescence assay. No acute toxicity was found in water samples taken from tanks after treatment of water hyacinth with the mycoherbicide.  相似文献   
948.
Candida albicans strains homozygous at the mating type locus can switch from white to opaque, and must do so to mate. Opaque cells then secrete mating pheromones that stimulate opaque cells of opposite mating type to undergo mating. These same pheromones stimulate mating-incompetent white cells to become cohesive and adhesive, and enhance white cell biofilm development, a pathogenic trait. Stimulation is mediated through the same receptor, G protein complex and mitogen-activated protein kinase pathway. Here we present evidence that a C. albicans -specific 55-amino-acid region of the first intracellular loop, IC1, of the α-pheromone receptor Ste2p, is required for the α-pheromone response of white cells, but not that of opaque cells. This represents a unique regulatory configuration in which activation of a common pathway by the same ligand, the same receptor and the same signal transduction pathway is dependent on a unique region of an intracellular loop of the common receptor in one of the two responding phenotypes.  相似文献   
949.
The objectives of this study were to determine the concentrations of free benzalkonium chloride (BAC) and apparent partitions coefficients (K m) in micelle solutions and to explore its application in formulation development. Ultrafiltration (UF) was carried out using 10K Nanosep® devices and centrifugation at 5,000 rpm for 5 min. The separation of free BAC from micellar solutions was also conducted using ultracentrifugation (UC) method for the comparison with UF method. Capillary electrophoresis method was used for the identification of micelles. Results showed that a UF method was applicable for quantitatively evaluating BAC–micelle interaction in micellar solutions. Unlike UF, UC could not completely separate free BAC from the micelles. The free BAC concentrations in the micelle solutions decreased with increasing surfactant concentrations. Among polysorbate 80, cremophor EL, and tyloxapol, BAC had the highest K m in polysorbate 80 solutions. The K m was significantly lower in non-buffered aqueous solutions than that in citric buffers. Moreover, increasing surfactant concentrations led to reducing antimicrobial activity. The UF is a rapid and accurate method that minimally alters the micellar equilibrium for the determination of free BAC and K m in micellar solutions. In conclusion, free BAC concentration, which is a function of surfactant type, surfactant concentration, and ion strength of solution, is likely associated with the antimicrobial activity.  相似文献   
950.
The Arc two-component signal transduction system of Escherichia coli comprises the ArcB sensor kinase and the ArcA response regulator. Under anoxic growth conditions, ArcB autophosphorylates and transphos-phorylates ArcA, which, in turn, represses or activates its target operons. ArcA has been shown to be able to autophosphorylate in vitro at the expense of acetyl-P. Here, the in vivo effect of acetyl phosphate on the redox signal transduction by the Arc system was assessed. Our results indicate that acetyl phosphate can modulate the expression of ArcA-P target genes only in the absence of ArcB. Therefore, the acetyl phosphate dependent ArcA phosphorylation route does not seem to play a significant role under physiological conditions.  相似文献   
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