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排序方式: 共有8397条查询结果,搜索用时 15 毫秒
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Julia Dietz Velia Chiara Di Maio Adolfo de Salazar Dolores Merino Johannes Vermehren Stefania Paolucci Andreas E. Kremer Magdalena Lara Maria Rodriguez Pardo Heinz Zoller Elisabetta Degasperi Kai-Henrik Peiffer Laura Sighinolfi Francisco Téllez Christiana Graf Valeria Ghisetti Jonas Schreiber Elisa Fernández-Fuertes Wolfgang Schmidt 《Journal of hepatology》2021,74(4):801-810
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Karin Stiasny Stefan Malafa Stephan W. Aberle Iris Medits Georgios Tsouchnikas Judith H. Aberle Heidemarie Holzmann Franz X. Heinz 《Viruses》2021,13(4)
Flaviviruses circulate worldwide and cause a number of medically relevant human diseases, such as dengue, Zika, yellow fever, and tick-borne encephalitis (TBE). Serology plays an important role in the diagnosis of flavivirus infections, but can be impeded by antigenic cross-reactivities among flaviviruses. Therefore, serological diagnosis of a recent infection can be insufficiently specific, especially in areas where flaviviruses co-circulate and/or vaccination coverage against certain flaviviruses is high. In this study, we developed a new IgM assay format, which is well suited for the specific diagnosis of TBE, Zika and dengue virus infections. In the case of TBE and Zika, the IgM response proved to be highly specific for the infecting virus. In contrast, primary dengue virus infections induced substantial amounts of cross-reactive IgM antibodies, which is most likely explained by structural peculiarities of dengue virus particles. Despite the presence of cross-reactive IgM, the standardized nature and the quantitative read-out of the assay even allowed the serotype-specific diagnosis of recent dengue virus infections in most instances. 相似文献
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Ziling Mao Jacqueline Roshelli Baker Masayoshi Takeuchi Hideyuki Hyogo Anne Tjønneland Anne Kirstine Eriksen Gianluca Severi Joseph Rothwell Nasser Laouali Verena Katzke Rudolf Kaaks Matthias B. Schulze Domenico Palli Sabina Sieri Maria Santucci de Magistris Rosario Tumino Carlotta Sacerdote Jeroen W. G. Derksen Inger T. Gram Guri Skeie Torkjel M. Sandanger Jose Ramón Quirós Marta Crous-Bou Maria-Jose Sánchez Pilar Amiano Sandra M. Colorado-Yohar Marcela Guevara Sophia Harlid Ingegerd Johansson Aurora Perez-Cornago Heinz Freisling Marc Gunter Elisabete Weiderpass Alicia K. Heath Elom Aglago Mazda Jenab Veronika Fedirko 《International journal of cancer. Journal international du cancer》2023,152(11):2257-2268
Glyceraldehyde-derived advanced glycation end products (glycer-AGEs) could contribute to colorectal cancer development and progression due to their pro-oxidative and pro-inflammatory properties. However, the association of glycer-AGEs with mortality after colorectal cancer diagnosis has not been previously investigated. Circulating glycer-AGEs were measured by competitive ELISA. Multivariable Cox proportional hazards models were used to calculate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for associations of circulating glycer-AGEs concentrations with CRC-specific and all-cause mortality among 1034 colorectal cancer (CRC) cases identified within the European Prospective Investigation into Cancer and Nutrition (EPIC) study between 1993 and 2013. During a mean of 48 months of follow-up, 529 participants died (409 from CRC). Glycer-AGEs were statistically significantly positively associated with CRC-specific (HRQ5 vs Q1 = 1.53, 95% CI: 1.04-2.25, Ptrend = .002) and all-cause (HRQ5 vs Q1 = 1.62, 95% CI: 1.16-2.26, Ptrend < .001) mortality among individuals with CRC. There was suggestion of a stronger association between glycer-AGEs and CRC-specific mortality among patients with distal colon cancer (per SD increment: HRproximal colon = 1.02, 95% CI: 0.74-1.42; HRdistal colon = 1.51, 95% CI: 1.20-1.91; Peffect modification = .02). The highest HR was observed among CRC cases in the highest body mass index (BMI) and glycer-AGEs category relative to lowest BMI and glycer-AGEs category for both CRC-specific (HR = 1.78, 95% CI: 1.02-3.01) and all-cause mortality (HR = 2.15, 95% CI: 1.33-3.47), although no statistically significant effect modification was observed. Our study found that prediagnostic circulating glycer-AGEs are positively associated with CRC-specific and all-cause mortality among individuals with CRC. Further investigations in other populations and stratifying by tumor location and BMI are warranted. 相似文献
5.
Merzenich Hiltrud Baaken Dan Schmidt Marcus Bekes Inga Schwentner Lukas Janni Wolfgang Woeckel Achim Bartkowiak Detlef Wiegel Thomas Blettner Maria Wollschläger Daniel Schmidberger Heinz 《Breast cancer research and treatment》2022,191(1):147-157
Breast Cancer Research and Treatment - Radiotherapy (RT) was identified as a risk factor for long-term cardiac effects in breast cancer patients treated until the 1990s. However, modern techniques... 相似文献
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Thomas Asendorf Robin Henderson Heinz Schmidli Tim Friede 《Statistics in medicine》2019,38(9):1503-1528
In some diseases, such as multiple sclerosis, lesion counts obtained from magnetic resonance imaging (MRI) are used as markers of disease progression. This leads to longitudinal, and typically overdispersed, count data outcomes in clinical trials. Models for such data invariably include a number of nuisance parameters, which can be difficult to specify at the planning stage, leading to considerable uncertainty in sample size specification. Consequently, blinded sample size re-estimation procedures are used, allowing for an adjustment of the sample size within an ongoing trial by estimating relevant nuisance parameters at an interim point, without compromising trial integrity. To date, the methods available for re-estimation have required an assumption that the mean count is time-constant within patients. We propose a new modeling approach that maintains the advantages of established procedures but allows for general underlying and treatment-specific time trends in the mean response. A simulation study is conducted to assess the effectiveness of blinded sample size re-estimation methods over fixed designs. Sample sizes attained through blinded sample size re-estimation procedures are shown to maintain the desired study power without inflating the Type I error rate and the procedure is demonstrated on MRI data from a recent study in multiple sclerosis. 相似文献
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Baldur P. Magnusson Heinz Schmidli Nicolas Rouyrre Daniel O. Scharfstein 《Statistics in medicine》2019,38(23):4761-4771
The treatment effect in subgroups of patients is often of interest in randomized controlled clinical trials, as this may provide useful information on how to treat which patients best. When a specific subgroup is characterized by the absence of certain events that happen postrandomization, a naive analysis on the subset of patients without these events may be misleading. The principal stratification framework allows one to define an appropriate causal estimand in such settings. Statistical inference for the principal stratum estimand hinges on scientifically justified assumptions, which can be included with Bayesian methods through prior distributions. Our motivating example is a large randomized placebo-controlled trial of siponimod in patients with secondary progressive multiple sclerosis. The primary objective of this trial was to demonstrate the efficacy of siponimod relative to placebo in delaying disability progression for the whole study population. However, the treatment effect in the subgroup of patients who would not relapse during the trial is relevant from both a scientific and patient perspective. Assessing this subgroup treatment effect is challenging as there is strong evidence that siponimod reduces relapses. We describe in detail the scientific question of interest, the principal stratum estimand, the corresponding analysis method for binary endpoints, and sensitivity analyses. Although our work is motivated by a randomized clinical trial, the approach has broader appeal and could be adapted for observational studies. 相似文献