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BACKGROUND: Evidence for the effectiveness of topical treatments, in providing symptomatic relief from ocular allergy, remains uncertain. AIMS: To assess the effectiveness and relative efficacy of topical treatments for the management of seasonal allergic conjunctivitis. DESIGN OF STUDY: A systematic review and meta-analysis. SETTING: A literature search of the Cochrane Library, Medline, and EMBASE bibliographic databases. METHOD: Double-masked randomised controlled trials were identified, that compared the use of topical mast cell stabilisers (sodium cromoglycate, nedocromil, lodoxamide) with placebo, topical antihistamines with placebo, and topical mast cell stabilisers with topical antihistamines. RESULTS: A meta-analysis of six trials showed that patients using sodium cromoglycate were 17 times (95% confidence interval [CI] = 4 to 78) more likely to perceive benefit compared with those using a placebo, although this estimate may be partially influenced by publication bias. Five trials indicated that those patients using nedocromil were 1.8 times (95% CI = 1.3 to 2.6) more likely to perceive their allergy to be moderately or totally controlled than those using a placebo. Four trials showed that those using antihistamines were 1.3 times (95% CI = 0.8 to 2.2) more likely to perceive a 'good' treatment effect than those using mast cell stabilisers, although this beneficial effect was not statistically significant. Limited evidence suggests that antihistamines might have a faster therapeutic effect compared to mast cell stabilisers. CONCLUSION: Overall, these findings confirm the benefit of topical mast cell stabilisers and antihistamines over placebo for the treatment of allergic conjunctivitis. There is, however, insufficient evidence to recommend the use of one type of medication over another. Treatment preferences should therefore be based on convenience of use (with reduced frequency of instillation for some preparations), patient preference, and costs, especially as important side effects were not reported with any medication.  相似文献   
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Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.   相似文献   
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It has been suggested that cellular immune responses to the hepatitis B virus are of importance in the production of liver cell damage in both acute and chronic hepatitis. An assay has now been developed which detects lymphocytes cytotoxic for target cells coated with the hepatitis B surface antigen (HBsAg). The reaction could be blocked by prolonged pre-incubation of lymphocytes with highly purified HBsAg and studies with lymphocyte subpopulations have shown that T lymphocytes were the principle effector cells.

When lymphocytes from twenty-three patients with acute hepatitis were used, cytotoxic T cells were demonstrable during the recovery phase, but not in the first 3 weeks of the illness. However, when these same lymphocytes were extensively washed, cytotoxicity was then detected in all the patients, even at the time of presentation. In patients with HBsAg-positive chronic liver disease the results with the standard assay were largely within the normal range, but again with extensive lymphocyte washing cytotoxicity was detected in all of the patients with untreated chronic active hepatitis and in five out of six with more minor histological lesions. The results in five carriers with normal liver histology were completely different, cytotoxicity remaining undetectable even after the extensive washing procedure.

The results suggest that blocking factors, possibly antigen or antigen–antibody complexes, could be interfering with the detection of sensitized T cells in patients with acute and chronic hepatitis, but that there is a true absence of sensitization to HBsAg in healthy carriers with normal liver histology.

  相似文献   
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The stability, accuracy, reproducibility, and predictive value of Sensititre MIC panels containing meropenem (Merrem) were evaluated by using National Committee for Clinical Laboratory Standards (NCCLS)-recommended American Type Culture Collection (ATCC) strains and 110 selected strains of rapidly growing and fastidious aerobes and anaerobes with various degrees of susceptibility to meropenem. The NCCLS-recommended agar dilution method was used as a standard reference method. Meropenem-containing Sensititre MIC panels were monitored for their stabilities at room temperature and reproducibilities over 24 months by using six ATCC strains. Ninety-nine percent of the MICs of both meropenem and imipenem obtained for NCCLS-recommended ATCC strains were within the established ranges after 2 years. The overall agreement (+/- 1 twofold dilution) between the Sensititre and the agar dilution meropenem MICs was greater than 93%. The predictive value of meropenem MICs for indicating suspeptibility or resistance obtained by the Sensititre method was greater than 90%. No major or very major interpretive errors were observed, and only 5% of meropenem MICs were associated with minor interpretive errors. Problematic organisms were not observed. The Sensititre MIC panels containing meropenem offer a convenient and valid alternative to the NCCLS reference method for the susceptibility testing of potential pathogens likely to be recovered from mixed infections.  相似文献   
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BACKGROUND: Attendance for routine asthma reviews is poor. A recent randomised controlled trial found that telephone consultations can cost-effectively and safely enhance asthma review rates; however, concerns have been expressed about the generalisability and implementation of the trial's findings. AIM: To evaluate the effectiveness of a telephone option as part of a routine structured asthma review service. DESIGN OF STUDY: Phase IV controlled before-and-after implementation study. SETTING: A large UK general practice. METHOD: Using existing administrative groups, all patients with active asthma (n = 1809) received one of three asthma review services: structured recall with a telephone-option for reviews versus structured recall with face-to-face-only reviews, or usual-care (to assess secular trends). Main outcome measures were: proportion of patients with active asthma reviewed within the previous 15 months (Quality and Outcomes Framework target), mode of review, enablement, morbidity, and costs to the practice. RESULTS: A routine asthma review was provided for 397/598 (66.4%) patients in the telephone-option group compared with 352/654 (53.8%) in the face-to-face-only review group: risk difference 12.6% (95% confidence interval [CI] = 7.2 to 17.9, P<0.001). The usual-care group achieved a review rate of 282/557 (50.6%). Morbidity was equivalent in the three groups; however, enablement (P = 0.03) and confidence (P = 0.007) in asthma management were greater in the telephone-option versus face-to-face-only group. The cost per review achieved by providing the telephone-option service was lower than the face-to-face-only service (10.03 pounds versus 12.74 pounds, mean difference 2.71 pounds; 95% CI = 1.92 to 3.50, P<0.001); usual-care costs were 11.85 pounds per review achieved. CONCLUSION: Routinely offering telephone reviews cost-effectively increased asthma review rates, enhancing patient enablement and confidence with management, with no detriment to asthma morbidity. Practices should consider a telephone option for their asthma review service.  相似文献   
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The development and application of fluorescence in-situ hybridization (FISH) has opened the way for comprehensive studies on numerical chromosome abnormalities in human spermatozoa. FISH can be rapidly applied to large numbers of spermatozoa and thus overcomes the major limitation of karyotyping spermatozoa after penetration of zona-free hamster oocytes. The simultaneous hybridization of two or more chromosome-specific probes to spermatozoa and subsequent detection of the bound probes using different fluorescent detection systems enables two or more chromosomes to be localized simultaneously in the same spermatozoon and provides a technique for undertaking reasonable estimates of aneuploidy. The most commonly used probes are those which bind to the centromeric region of specific chromosomes. Most studies to date have concentrated on estimating aneuploidy in spermatozoa from normospermic men, although reports are beginning to appear on aneuploidy in spermatozoa from subfertile and infertile men. Multi- probe FISH studies have generally reported disomy (hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary evidence that some chromosomes such as X, Y and 21 are predisposed towards higher rates of non-disjunction during spermatogenesis. There are also suggestions of inter-donor variability in aneuploidy frequencies for specific chromosomes, although this requires confirmation in larger studies. While FISH is clearly a powerful technique that has many applications in reproductive medicine, it must also be realized that it does have limitations and the technology itself is still evolving and has yet to be fully validated on spermatozoa.   相似文献   
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