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71.
ObjectiveTo examine the anatomical characteristics of impacted maxillary third molars to help predict and prevent possible adverse events during extraction.MethodsThis retrospective study enrolled young Japanese patients that were assessed for third molar extraction. Patients with maxillary third molar impaction presenting with no space between the maxillary second molar and the occlusal surface of the maxillary third molar were analysed using computed tomography data.ResultsIn this study, a total of 663 patients aged 20–29 years were examined for third molar extraction and 26 teeth in 23 patients were analysed. The mean ± SD angle between the second and third molar axes was 54.2° ± 7.5° and the mean ± SD length of the maxillary third molar was 16.1 ± 1.9 mm. The maxillary third molars showed close or extensive contact with the maxillary sinus and computed tomography did not show any bone from the maxillary sinus floor. Furthermore, in all patients, the crowns of the third molars were not completely covered by the alveolar bone.ConclusionsMaxillary third molars with horizontal impaction showed close or extensive contact with the maxillary sinus and their crowns were not completely covered by the alveolar bone.  相似文献   
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The primary objective of this study was to investigate the tolerability, efficacy and pharmacokinetic profile of gemtuzumab ozogamicin (GO) in patients with relapsed and/or refractory CD33-positive acute myeloid leukemia (AML). Patients received 2-h infusions of GO twice with an interval of approximately 14 days. Tolerability was assessed using the National Cancer Institute Common Toxicity Criteria Version 2.0. Samples for pharmacokinetics were taken on day 1 and day 8 of the first treatment cycle. The dose was increased stepwise and, in each cohort, patients were treated at the same dose. Forty patients, median age 58 years (range 28–68) were treated; 20 and 20 patients were enrolled to the phase I and II parts, respectively. In the phase I part, dose-limiting toxicities (DLTs) were hepatotoxicities, and the recommended dose was established as 9 mg/m2 given as two intravenous infusions separated by approximately 14 days. The pharmacokinetic study revealed that C max and AUC were equivalent to those of non-Japanese patients. In the phase II part, complete remission was observed in 5 patients, and one patient had complete remission without platelet recovery. Four of these 6 in remission and one in the phase I are long-term survivors (alive for at least 44 months). GO is safe and effective as a single agent among Japanese CD33-positive AML patients. Remission lasted longer in a subset of patients than in non-Japanese patients in earlier studies. Further studies of this agent are warranted to establish standard therapy. S. Furusawa: deceased.  相似文献   
73.
Primary open-angle glaucoma (POAG) is the major type of glaucoma. To discover genetic markers associated with POAG, we examined a total of 1,575 Japanese subjects in a genome-wide association study (stage 1) and a subsequent study (stage 2). Both studies were carried out at a single institution. In the stage 1 association study, we compared SNPs between 418 POAG patients and 300 control subjects. First, low-quality data were eliminated by a stringent filter, and 331,838 autosomal SNPs were selected for analysis. Poorly clustered SNPs were eliminated by a visual assessment, leaving 255 that showed a significant deviation (P < 0.001) in the allele frequency comparison. In the stage 2 analysis, we tested these 255 SNPs for association in DNA samples from a separate group of 409 POAG and 448 control subjects. High-quality genotype data were selected and used to calculate the combined P values of stages 1 and 2 by the Mantel–Haenszel test. These analyses yielded 6 SNPs with P < 0.0001. All 6 SNPs showed a significant association (P < 0.05) in stage 2, demonstrating a confirmed association with POAG. Although we could not link the SNPs to the annotated gene(s), it turned out that we have identified 3 genetic loci probably associated with POAG. These findings would provide the foundation for future studies to build on, such as for the metaanalysis, to reveal the molecular mechanism of the POAG pathogenesis.  相似文献   
74.
Summary Large plaque (G) and small plaque (8) variants were cloned from stock culture of Sindbis virus. Addition of protamine to agar overlay was shown to have little or no effect on the size of plaques produced by G variant, whereas S virus plaque size was significantly increased. This finding suggests that the S variant is more susceptible than the G variant to the inhibitory action of agar factor. The G and S variants differed markedly in their sensitivity to the antiviral action of interferon. Evidence was obtained that the S variant is more susceptible to the action of interferon. The difference of G and S variants in susceptibility to the action of interferon and agar factor may account for the difference of their plaque size. Growth and cytopathic effect of the S variant in a HVJ carrier HeLa cell culture (HeLaHVJ) was greatly enhanced in contrast to those in normal HeLa cells. Enhancement of growth of wild-type virus in HeLaHVJ cells was not so significant as in the case of the S variant. These observations were discussed in relations to the properties of the S variant and the cells of HeLaHVJ.Dedicated to ProfessorJohn F. Enders on the occasion of his 70th birthday.  相似文献   
75.
The movement protein (MP) of tobacco mosaic virus (TMV) mediates the transport of viral RNA from infected cells to neighboring uninfected cells via plasmodesmata by interacting with putative host factors. To find such host factors, we screened tobacco proteins using the yeast two-hybrid system. NtMPIP1, a novel subset of DnaJ-like proteins, was identified from a tobacco cDNA library, and its specific interaction with TMV MP was confirmed with an in vitro filter-binding assay. In a deletion analysis, using a series of truncated TMV MPs and NtMPIP1s, at least two regions of TMV MP, amino acid residues 65–86 and 120–185, conferred the ability to interact with the C-terminal domain of NtMPIP1, which is thought to be involved in substrate binding. Virus-induced gene silencing of NtMPIP1 significantly inhibited the spread of TMV. Therefore, it is reasonable to consider that endogenous NtMPIP1 is a host factor involved in virus cell-to-cell spread by interacting with TMV MP. Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB092334.  相似文献   
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Background Orotate phosphoribosyltransferase (OPRT; EC 2.4.2.10), a key enzyme that catalyzes one of the primary steps in the phosphorylation of fluoropyrimidine, was recently recognized as an important enzyme that determines the anticancer effects of the dihydropyrimidine dehydrogenase-inhibitory fluoropyrimidine, S-1. Methods Levels of OPRT were examined in 97 gastric carcinoma tissues and 65 normal gastric mucosa tissues obtained from patients with gastric carcinoma. The relation between OPRT levels and clinicopathological variables was evaluated, and correlations of OPRT with thymidylate synthase and dihydropyrimidine dehydrogenase levels in gastric carcinoma tissues were evaluated. Results Although OPRT levels were high in well-differentiated and localized carcinomas, they were not correlated with other clinicopathological variables or with the pathological stage of gastric carcinoma. Levels of OPRT were significantly higher in gastric carcinoma tissue than in normal gastric mucosa. OPRT levels were not correlated with levels of either thymidylate synthase or dihydropyrimidine dehydrogenase. In samples of gastric carcinoma tissues and normal gastric mucosa tissues obtained simultaneously from 24 patients, no correlation was found between OPRT levels in gastric carcinoma and levels in normal gastric mucosa. Conclusion These results suggest that the OPRT level is significantly higher in gastric carcinoma tissue than in normal gastric mucosa and that the OPRT level in gastric carcinoma is a novel variable that is independent of the levels of other previously known enzymes related to 5-fluorouracil (FU) metabolism.  相似文献   
78.
BACKGROUND AND OBJECTIVE: Several statistical methods exist for detecting signals of potential adverse drug reactions in spontaneous reporting databases. However, these signal-detection methods were developed using regulatory databases, which contain a far larger number of adverse event reports than the databases maintained by individual pharmaceutical manufacturers. Furthermore, the composition and quality of the spontaneous reporting databases differ between regulatory agencies and pharmaceutical companies. Thus, the signal-detection criteria proposed for regulatory use are considered to be inappropriate for pharmaceutical industry use without modification. The objective of this study was to revise the criteria for signal detection to make them suitable for use by pharmaceutical manufacturers. METHODS: A model comprising 40 drugs and 1000 adverse events was constructed based on a spontaneous reporting database provided by a pharmaceutical company and used in a simulation to investigate appropriate criteria for signal detection. In total, 1000 pseudo datasets were generated with this model, and three statistical methods (proportional reporting ratio [PRR], Bayesian Confidence Propagation Neural Network [BCPNN] and multi-item gamma Poisson shrinker [MGPS]) for signal detection were applied to each dataset. The sensitivity and specificity of each method were evaluated using these pseudo datasets. The optimum critical value for signal detection (i.e. the value that achieved the highest sensitivity with 95% specificity) was identified for each method. The optimum values were also examined with the adverse events classified into two categories according to frequency. The three original detection methods and their revised versions were applied to a real pharmaceutical company database to detect 173 known adverse reactions of four drugs. RESULTS: The 1000 pseudo datasets consisted of an average of 81 862 reports and 11,407 drug-event pairs, including 1192 adverse drug reactions. The sensitivities of PRR, BCPNN and MGPS methods were 49%, 45% and 26%, respectively, whereas their specificities were 95%, 99.6% and 99.99%, respectively; these sensitivities were unacceptably low for pharmaceutical manufacturers, whereas the specificities were acceptable. The highest sensitivity for each method, obtained by changing critical values and maintaining specificity at 95%, was 44%, 62% and 62%, respectively. When adverse events were classified into two categories, sensitivities as high as 75% for regular events and 39% for rare events were achieved with the revised BCPNN method. The critical values of the information component minus two standard deviations (IC - 2SD) index of the revised BCPNN method were greater than -0.7 for regular events and greater than -0.6 for rare events. The revised BCPNN method yielded 51% sensitivity and 89% specificity for the real dataset. CONCLUSION: A lower critical value may be needed when signal-detection methodology is applied to the spontaneous reporting databases of pharmaceutical manufacturers. For example, it is recommended that pharmaceutical manufacturers use the BCPNN method with IC - 2SD criteria of greater than -0.7 for regular events and greater than -0.6 for rare events.  相似文献   
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