全文获取类型
收费全文 | 979篇 |
免费 | 66篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 50篇 |
妇产科学 | 10篇 |
基础医学 | 107篇 |
口腔科学 | 12篇 |
临床医学 | 61篇 |
内科学 | 235篇 |
皮肤病学 | 84篇 |
神经病学 | 62篇 |
特种医学 | 12篇 |
外科学 | 177篇 |
综合类 | 14篇 |
预防医学 | 57篇 |
眼科学 | 13篇 |
药学 | 56篇 |
中国医学 | 6篇 |
肿瘤学 | 89篇 |
出版年
2023年 | 7篇 |
2022年 | 28篇 |
2021年 | 41篇 |
2020年 | 20篇 |
2019年 | 39篇 |
2018年 | 33篇 |
2017年 | 23篇 |
2016年 | 24篇 |
2015年 | 28篇 |
2014年 | 44篇 |
2013年 | 45篇 |
2012年 | 78篇 |
2011年 | 66篇 |
2010年 | 26篇 |
2009年 | 32篇 |
2008年 | 44篇 |
2007年 | 48篇 |
2006年 | 48篇 |
2005年 | 33篇 |
2004年 | 34篇 |
2003年 | 30篇 |
2002年 | 20篇 |
2001年 | 14篇 |
2000年 | 21篇 |
1999年 | 17篇 |
1998年 | 6篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1993年 | 4篇 |
1992年 | 9篇 |
1991年 | 11篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 4篇 |
1987年 | 10篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1982年 | 4篇 |
1975年 | 6篇 |
1968年 | 3篇 |
1921年 | 3篇 |
1916年 | 3篇 |
1915年 | 7篇 |
1914年 | 5篇 |
1913年 | 8篇 |
1912年 | 17篇 |
1911年 | 15篇 |
1910年 | 8篇 |
1902年 | 3篇 |
排序方式: 共有1061条查询结果,搜索用时 15 毫秒
31.
Shahmiri Shahab Shahabi Eghbali Foolad Ismaeil Aiman Gholizadeh Barmak Khalooeifard Razieh Valizadeh Rohollah Rokhgireh Samaneh Kermansaravi Mohammad 《Obesity surgery》2022,32(5):1719-1725
Obesity Surgery - This study review the prevalence of selenium deficiency after bariatric surgery, incidence, and symptoms. A systematic literature search and meta-analysis was performed... 相似文献
32.
Shahab Nozohoor Josef Stehlik Lars H. Lund David Ansari Bodil Andersson Johan Nilsson 《Clinical transplantation》2020,34(7):e13871
Although the use of induction therapy has reduced the risk of acute rejection after heart transplantation, its use may be associated with other adverse outcomes. We aimed to examine the effect of no induction (NoInd), induction with basiliximab (BAS), or induction with antithymocyte globulin (ATG) on outcome after heart transplantation. We analyzed data from the International Society for Heart and Lung Transplantation (ISHLT) registry for adult heart transplants performed between 2000 and 2013. The primary outcome was cumulative all-cause mortality, and the secondary outcome was cause-specific death. We identified 27 369 transplants whose recipients received NoInd (n = 15 688), ATG (n = 6830), or BAS (n = 4851). Over a median follow-up of 1497 days, overall 30-day mortality was 5% and 1-year mortality was 11%. Survival after transplant was similar in patients treated with NoInd compared with ATG. The survival was improved using NoInd compared with BAS (log-rank P = .040), adjustment HR = 1.11 (95% CI, 1.04-1.19). Compared to NoInd, BAS was associated with higher risk of graft failure-related deaths, HR = 1.27 (95% CI, 1.02-1.58), and ATG was associated with higher risk of malignancy-related deaths, HR = 1.18 (95% CI, 1.01-1.39). Survival of patients who received NoInd was similar to ATG and better compared with BAS. Further, the use of ATG may be associated with increased malignancy-related mortality, compared with NoInd. 相似文献
33.
34.
Peter Asaad Adam O’Connor Shahab Hajibandeh Shahin Hajibandeh 《World journal of gastrointestinal endoscopy》2021,13(5):137-154
BACKGROUND In an effort to further reduce the morbidity and mortality profile of laparoscopic cholecystectomy, the outcomes of such procedure under regional anesthesia(RA) have been evaluated. In the context of cholecystectomy, combining a minimally invasive surgical procedure with a minimally invasive anesthetic technique can potentially be associated with less postoperative pain and earlier ambulation.AIM To evaluate comparative outcomes of RA and general anesthesia(GA) in patients undergoing laparoscopic cholecystectomy.METHODS A comprehensive systematic review of randomized controlled trials with subsequent meta-analysis and trial sequential analysis of outcomes were conducted in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement standards.RESULTS Thirteen randomized controlled trials enrolling 1111 patients were included. The study populations in the RA and GA groups were of comparable age(P = 0.41),gender(P = 0.98) and body mass index(P = 0.24). The conversion rate from RA to GA was 2.3%. RA was associated with significantly less postoperative pain at 4 h [mean difference(MD):-2.22, P 0.00001], 8 h(MD:-1.53, P = 0.0006), 12 h(MD:-2.08, P 0.00001), and 24 h(MD:-0.90, P 0.00001) compared to GA. Moreover, it was associated with significantly lower rate of nausea and vomiting [risk ratio(RR): 0.40, P 0.0001]. However, RA significantly increased postoperative headaches(RR: 4.69, P = 0.03), and urinary retention(RR: 2.73, P = 0.03). The trial sequential analysis demonstrated that the meta-analysis was conclusive for most outcomes, with the exception of a risk of type 1 error for headache and urinary retention and a risk of type 2 error for total procedure time.CONCLUSION Our findings indicate that RA may be an attractive anesthetic modality for daycase laparoscopic cholecystectomy considering its associated lower postoperative pain and nausea and vomiting compared to GA. However, its associated risk of urinary retention and headache and lack of knowledge on its impact on procedure-related outcomes do not justify using RA as the first line anesthetic choice for laparoscopic cholecystectomy. 相似文献
35.
36.
37.
38.
Seyedeh-Nafiseh Hassani Mehdi Totonchi Ali Sharifi-Zarchi Sepideh Mollamohammadi Mohammad Pakzad Sharif Moradi Azam Samadian Najmehsadat Masoudi Shahab Mirshahvaladi Ali Farrokhi Boris Greber Marcos J. Araúzo-Bravo Davood Sabour Mehdi Sadeghi Ghasem Hosseini Salekdeh Hamid Gourabi Hans R. Schöler Hossein Baharvand 《Stem cell reviews》2014,10(1):16-30
39.
Sylvain Gandon Sbastien Lion 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(3)
The limited supply of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raises the question of targeted vaccination. Many countries have opted to vaccinate older and more sensitive hosts first to minimize the disease burden. However, what are the evolutionary consequences of targeted vaccination? We clarify the consequences of different vaccination strategies through the analysis of the speed of viral adaptation measured as the rate of change of the frequency of a vaccine-adapted variant. We show that such a variant is expected to spread faster if vaccination targets individuals who are likely to be involved in a higher number of contacts. We also discuss the pros and cons of dose-sparing strategies. Because delaying the second dose increases the proportion of the population vaccinated with a single dose, this strategy can both speed up the spread of the vaccine-adapted variant and reduce the cumulative number of deaths. Hence, strategies that are most effective at slowing viral adaptation may not always be epidemiologically optimal. A careful assessment of both the epidemiological and evolutionary consequences of alternative vaccination strategies is required to determine which individuals should be vaccinated first.The development of effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raises hope regarding the possibility of eventually halting the ongoing pandemic. However, vaccine supply shortages have sparked a debate about the optimal distribution of vaccination among different categories of individuals. Typically, infections with SARS-CoV-2 are far more deadly in older individuals than in younger ones (1). Prioritizing vaccination for older classes may thus provide a direct benefit in terms of mortality (2, 3). Yet, younger individuals are usually more active, and consequently, they may contribute more to the spread of the epidemic. Prioritizing vaccination for younger and more active individuals may thus provide an indirect benefit through a reduction of the epidemic size (4, 5). Earlier studies have compared alternative ways to deploy vaccination in heterogeneous host populations and showed that recommendation varies with the choice of the quantity one is trying to minimize (e.g., the cumulative number of deaths, the remaining life expectancy, or the number of infections) (3, 6, 7). The recommendation also varies with the properties of the pathogen and the efficacy of the vaccine (3, 4, 8). For SARS-CoV-2, the increase in mortality with age is such that the direct benefit associated with vaccinating more vulnerable individuals tends to overwhelm the indirect benefits obtained from vaccinating more active individuals (2, 3, 9, 10). However, some studies challenge this view and identified specific conditions where vaccinating younger and more active classes could be optimal (5, 7, 11, 12). A similar debate emerges over the possibility to delay the second vaccination dose to maximize the number of partially vaccinated individuals. A quantitative exploration of alternative vaccination strategies can help provide useful recommendations: a two-dose strategy is recommended when the level of protection obtained after the first dose is low and/or when vaccine supply is large (13–16).Vaccine-driven evolution, however, could erode the benefit of vaccination and alter the above recommendations which are based solely on the analysis of epidemiological dynamics. Given that hosts differ both in their sensitivity to the disease and in their contribution to transmission, who should we vaccinate first if we want to minimize the spread of vaccine-adapted variants? The effect of alternative vaccination strategies on the speed of pathogen adaptation remains unclear. Previous studies of adaptation to vaccines focused on long-term evolutionary outcomes (17, 18). These analyses are not entirely relevant for the ongoing pandemic because what we want to understand first is the short-term consequence of different vaccination strategies (19). A few studies have discussed the possibility of SARS-CoV-2 adaptation following different targeted vaccination strategies but did not explicitly account for evolutionary dynamics (12, 20). A recent simulation study explored the effect of a combination of vaccination and social distancing strategies on the probability of vaccine-driven adaptation (21). This model, however, did not study the impact of targeted vaccination strategies on the speed of adaptation.Here we develop a theoretical framework based on the analysis of the deterministic dynamics of multiple variants after they successfully managed to reach a density at which they are no longer affected by the action of demographic stochasticity. We study the impact of different vaccination strategies on the rate of change of the frequency of a novel variant, which allows us to quantify the speed of virus adaptation to vaccines. Numerical simulations tailored to the epidemiology of SARS-CoV-2 confirm the validity of our approximation of the strength of selection for vaccine-adapted variants. 相似文献
40.
Management of adenovirus infection in patients after haematopoietic stem cell transplantation: State‐of‐the‐art and real‐life current approach 下载免费PDF全文
Prashant Hiwarkar Karin Kosulin Simone Cesaro Malgorzata Mikulska Jan Styczynski Robert Wynn Thomas Lion 《Reviews in medical virology》2018,28(3)
The important insights gained over the past years in diagnosis and treatment of invasive adenoviral infections provide new paradigms for the monitoring and clinical management of these life‐threatening complications. A meeting was held to discuss and subsequently disseminate the current advances in our understanding of the aetiology/pathogenesis and future treatment options facilitating effective control or prevention of adenovirus‐related diseases in the allogeneic haematopoietic stem cell transplant setting. Invited experts in the field discussed recent progress with leading members of the Infectious Diseases Working Party of the European Society of Blood and Marrow Transplantation at the “State‐of‐the‐art” Meeting in Poznan, Poland, in October 2017. In this review article, the panel of experts presents a concise summary of the current evidence based on published data from the last 15 years and on recent achievements resulting from real‐life practice. The present position statement reflects an expert opinion on current approaches to clinical management of adenovirus infections in patients undergoing allogeneic haematopoietic stem cell transplant and provides graded recommendations of the panel for diagnostic approaches and preemptive therapy reflecting the present state of knowledge. 相似文献