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891.
A genetic variation was found in pancreatic esterases of Japanese quail which appeared to be arylesterase. It was found on the cathode side in the agar gel electrophoresis. Three phenotypes, A, B and AB, were observed. These phenotypes were shown to be controlled by one autosomal locus, designated as Es-4 , with co-dominant alleles Es-4A and Es-4B.
Es-4 esterase isozymes were detected in all the individuals from about 4 days of age, but the activity was very weak. However, it gradually increased to reach a level almost the same as that of a mature quail from about 15 days of age.  相似文献   
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ObjectiveEmerging evidence supports the favorable cardiovascular health in nonobese subjects with healthy metabolism. However, little is known regarding the prognosis across the range of metabolic phenotypes once cardiovascular disease is established. We examined the prognosis of patients with acute myocardial infarction (AMI) stratified according to metabolic health and obesity status.MethodsThis is a retrospective study on consecutive patients with AMI admitted to a tertiary hospital between 2014 and 2021. Patients were allocated into the following 4 groups based on metabolic and obesity profile: (1) metabolically healthy obese (MHO), (2) metabolically healthy nonobese (MHNO), (3) metabolically unhealthy obese (MUO), and (4) metabolically unhealthy nonobese (MUNO). Metabolic health was defined in accordance to the Biobank Standardisation and Harmonisation for Research Excellence in the European Union Healthy Obese Project. The primary outcome was all-cause mortality. The Cox regression analysis examined the independent association between mortality and metabolic phenotypes, adjusting for age, sex, AMI type, chronic kidney disease, smoking status, and left ventricular ejection fraction.ResultsOf 9958 patients, the majority (68.5%) were MUNO, followed by MUO (25.1%), MHNO (5.6%), and MHO (0.8%). MHO had the lowest mortality (7.4%), followed by MHNO (9.7%), MUO (19.2%), and MUNO (22.6%) (P < .001). Compared with MHNO, MUO (hazard ratio [HR], 1.737; 95% confidence interval [CI], 1.282-2.355; P < .001) and MUNO (HR, 1.482; 95% CI, 1.108-1.981; P = .008) had a significantly higher mortality risk but not MHO (HR, 1.390; 95% CI, 0.594-3.251; P = .447), after adjusting for confounders. The Kaplan-Meier curves showed favorable survival in the metabolically healthy and obesity groups, with the highest overall survival in the MHO, followed by MHNO, MUO, and MUNO (P < .001).ConclusionMetabolically healthy and obese patients with AMI have favorable prognosis compared with metabolically unhealthy and nonobese patients. It is equally important to prioritize intensive metabolic risk factor management to weight reduction in the early phase after AMI.  相似文献   
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Species-specific enumeration of mixed community is invaluable as it facilitates a better understanding of the significance of the individual strains, their interactions, and the underlying mechanisms of community dynamics. Mixed microbial community has been characterized by microbiological, biochemical, or molecular biology-based methods. While microbiological and biochemical techniques do not provide adequate quantitative information of the members of the consortia and require additional techniques for a more comprehensive analysis, molecular biology-based methods analyze the microbial consortium based on specific DNA sequences and do not require isolation and culturing of bacteria for quantitative analysis. These methods outshine conventional culture-based techniques in terms of better sensitivity, reproducibility, and reliability. Quantitative molecular biology methods have been classified as PCR-based and probe hybridization methods. The PCR-based methods includes quantitative real-time PCR and terminal restriction fragment length polymorphism, while fluorescent in situ hybridization and DNA microarrays fall under probe hybridization methods. The workflow, the quantification methods, and their potential applications are discussed in this review by highlighting their advantages and possible limitations.  相似文献   
897.
The physiologically active form of p53 consists of a tetramer of four identical 393-amino-acid subunits associated via their tetramerization domains (TDs; residues 325-355). One in two human tumors contains a point mutation in the DNA binding domain (DBD) of p53 (residues 94-312). Most existing studies on the effects of these mutations on p53 structure and function have been carried out on the isolated DBD fragment, which is monomeric. Recent structural evidence, however, suggests that DBDs may interact with each other in full-length tetrameric forms of p53. Here, we investigate the effects of tumorigenic DBD mutations on the folding of p53 in its tetrameric form. We employ the construct consisting of DBD and TD (amino acids 94-360). We characterize the stability and conformational state of the tumorigenic DBD mutants R248Q, R249S, and R282Q using equilibrium denaturation and functional assays. Destabilizing mutations cause DBD to misfold when it is part of the p53 tetramer, but not when it is monomeric. This conformation is populated under moderately destabilizing conditions (10 °C in 2 M urea, and at physiological temperature in the absence of denaturant). Under those same conditions, it is not present in the isolated DBD fragment or in the presence of the TD mutation L344P, which abolishes tetramerization. Misfolding appears to involve intramolecular DBD-DBD association within a single tetrameric molecule. This association is promoted by destabilization of DBD (caused by mutation or elevated temperature) and by the high local DBD concentration enforced by tetramerization of TD. Disrupting the nonnative DBD-DBD interaction or transiently inhibiting tetramerization and allowing p53 to fold as a monomer may be potential strategies for pharmacological intervention in cancer.  相似文献   
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T T Loh 《Life sciences》1983,32(8):915-920
Measurement of the distribution of the four species of transferrin, viz, apotransferrin, diferric transferrin and the two monoferric transferrin, before and after incubation of iron-rich rabbit transferrin with rabbit reticulocytes showed that not all transferrin released from the cells were in the form of apotransferrin. Instead, a mixture of all four species of the protein was released with apotransferrin and C-terminal monoferric transferrin being the major fractions. The buffer solution containing 125I-labelled transferrin showed a continuous gain in percentages in apotransferrin and C-terminal monoferric transferrin after each incubation with reticulocytes. The N-terminal monoferric transferrin, however, remained unchanged suggesting that in the process of transferrin uptake by cells, the diferric transferrin releases its iron from the acid-labile site at N-domain first before the other iron from the acid-stable site.  相似文献   
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