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41.
An in vitro is described that attempts to detect patients with a potential for adverse systemic reactions to contrast material. This test involves measuring the rate of conversion of prekallikrein to kallikrein under certain standard conditions. In a preliminary retrospective study, the test could be used to identify such patients with a sensitivity of 88%, a specificity of 82%, and a predictive value of 79%. 相似文献
42.
Patient dosage in computed tomography 总被引:1,自引:0,他引:1
43.
Nienhuijs S Kortmann B Boerma M Strobbe L Rosman C 《Archives of surgery (Chicago, Ill. : 1960)》2004,139(10):1097-1100
HYPOTHESIS: Surgeons' preferences for any of 3 methods of inguinal hernia repair are comparable in terms of operating time, incision length, perceived difficulty, and surgeon's satisfaction. DESIGN: Randomized patient-blinded study. SETTING: Teaching hospital. PATIENTS: A total of 334 patients randomized to receive 1 of the 3 repairs. INTERVENTIONS: Patients underwent hernia repair with the Prolene Hernia System, mesh plug repair, or Lichtenstein technique. MAIN OUTCOME MEASURES: Operating variables, surgeon's rating of satisfaction and difficulty, grade and experience of the operating team, and complications. RESULTS: The Lichtenstein technique took significantly the longest operating time (52 minutes vs 41 or 42 minutes; P<.001). The mesh plug repair scored the best results in difficulty and satisfaction. Overall, surgeons having performed more than 5 procedures rated the repairs less difficult and with significantly more satisfaction (P<.001 and P = .001, respectively). The complication rate did not differ between the treatment groups. None of the operative findings was correlated to the outcome, except for adverse correlation with the body mass index. CONCLUSION: From a surgeon's point of view, the mesh plug repair is superior to the Lichtenstein technique and the Prolene Hernia System in terms of operating time, incision length, perceived difficulty, and surgeon's satisfaction. 相似文献
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In population-based surveys on sexual behaviour, men consistently report higher numbers of sexual partners than women, which may be associated with male exaggeration or female under-reporting or with issues related to sampling, such as exclusion of female sex workers. This paper presents an analysis of data collected in the context of a longitudinal study in rural Tanzania, where a sexual partnership module was applied to all participating men and women in the study population. Since the study design included all men and women of reproductive ages and did not involve sampling, these data provide a unique opportunity to compare the consistency of aggregate measures of sexual behaviour between men and women living in the same villages. The analysis shows that non-marital partnerships were common amongst single people of both sexes--around 70% of unmarried men and women report at least one sexual partner in the last year. However, 40% of married men also report having non-marital partners, but only 3% of married women did so. Single women reported about half as many multiple partnerships in the last year as men. Under-reporting of non-marital partnerships was much more common among single women than among married women and men. Furthermore, women were more likely to report longer duration partnerships and partnership with urban men or more educated men than with others. If a woman reports multiple partners, biological data indicate that she is at high risk of contracting HIV. For men, however, there is only a weak association between number of partnerships and the risk of HIV, and it cannot be excluded that men, especially single men, exaggerate the number of sexual partners. 相似文献
48.
Elbourne D Ayers S Dellagrammaticas H Johnson A Leloup M Lenoir-Piat S;EC Ethamsylate Trial Group 《Archives of disease in childhood. Fetal and neonatal edition》2001,84(3):F183-F187
AIM: To assess the role of etamsylate in reducing the risk of haemorrhagic brain damage and its consequences. DESIGN: Follow up of babies recruited into a randomised controlled trial. METHODS: A total of 334 infants born before 33 weeks gestation in France and Greece were randomly allocated within the first four hours of birth either to receive etamsylate or to act as controls. The principal outcomes in the trial were death or impairment and/or disability at the age of 2 years. RESULTS: Fifty nine children were lost to follow up. A total of 115 (34%) either died or had some impairment or disability, and 88 (26%) either died or had severe impairment or disability at 2 years of age. These outcomes did not differ significantly between the two randomised groups: relative risks and 95% confidence intervals 1.14 (0.78 to 1.4) and 1.17 (0.82 to 1.68) respectively. The findings were similar for all the prespecified subgroup analyses stratified by key prognostic factors at trial entry: country of birth, gestational age < or >or= 29 weeks, inborn or outborn, age < or >or= 1 hour, and with or without cerebral scan abnormality. CONCLUSION: These findings do not support the use of etamsylate. Other strategies need to be evaluated for the prevention of mortality and morbidity in these vulnerable infants. 相似文献
49.
Ordered recombination of immunoglobulin light chain genes occurs at the IGK locus but seems less strict at the IGL locus 总被引:7,自引:2,他引:5
van der Burg M Tümkaya T Boerma M de Bruin-Versteeg S Langerak AW van Dongen JJ 《Blood》2001,97(4):1001-1008
Regulation of allelic and isotypic exclusion of human immunoglobulin (Ig) light-chain genes was studied in 113 chronic B-cell leukemias as a "single-cell" model that allowed complete analysis of each light chain allele. Our data show that monospecific Ig light chain expression is in about 90% of cases determined by ordered recombination: Igkappa gene (IGK) rearrangements, followed by IGK deletions and Iglambda gene (IGL) rearrangements, resulting in the presence of only one functional Ig light chain rearrangement. In about 10% (10 cases), 2 functional Ig light chain rearrangements (IGK/IGL or IGL/IGL, but not IGK/IGK) were identified. This might be explained by the fact that regulation of the ordered recombination process is not fully strict, particularly when the IGL locus is involved. Unfavorable somatic mutations followed by receptor editing might have contributed to this finding. Eight of these 10 cases indeed contained somatic mutations. In cases with 2 functional Ig light chain rearrangements, both alleles were transcribed, but monospecific Ig expression was still maintained. This suggests that in these cases allelelic exclusion is not regulated at the messenger RNA level but either at the level of translation or protein stability or via preferential pairing of Ig light and Ig heavy chains. Nevertheless, ordered rearrangement processes are the main determinant for monospecific Ig light chain expression. 相似文献
50.
Looking for change in response to the AIDS epidemic: trends in AIDS knowledge and sexual behavior in Zambia, 1990 through 1998 总被引:4,自引:0,他引:4
Bloom SS Banda C Songolo G Mulendema S Cunningham AE Boerma JT 《Journal of acquired immune deficiency syndromes (1999)》2000,25(1):77-85
This study investigates trends in AIDS knowledge and sexual behavior among men and women in urban Lusaka 1990 to 1998, and in all of Zambia, 1992 to 1998. Using data from representative surveys of urban Lusaka and of the country as a whole, population proportions were estimated to examine trends in knowledge and sexual risk behaviors. Differences in the estimated proportions between 1990 and 1998 were tested in Lusaka. In all Zambia, tests of difference were conducted between the earliest and latest years for which data were available for each indicator. A decline in premarital sexual activity was observed in urban Lusaka. In 1990, 50% of never married women reported no sexual experience, compared with 60% in 1998 (p =. 003); among men, the figures were 38% and 53%, respectively (p <. 001). Fewer women (1990, 8%; 1998, 2%; p <.001) and men (1990, 31%; 1998, 19%; p =.07) had extramarital partners. The bulk of change observed in urban Lusaka took place from 1990 to 1996; the changes in men's behavior observed between 1996 and 1998 were also observed in the national estimates for those years. National figures for other indicators from 1992 to 1998 were less encouraging. Apart from an increase in having ever used condoms, no change in women's sexual behavior was observed. Fewer men had premarital sex from 1996 to 1998 (1996, 64%; 1998, 46%; p <.001), but condom use with nonregular partners decreased among men (1996, 38%; 1998, 29%; p =.02). Prevention campaigns focused on education about AIDS and promoting safer sexual behavior appear to have made a difference in the early 1990s in Zambia. Findings from more recent years indicate that further change has stagnated. Renewed efforts are needed, particularly targeting condom use with nonregular partners. 相似文献