首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   15480篇
  免费   1188篇
  国内免费   607篇
耳鼻咽喉   67篇
儿科学   178篇
妇产科学   151篇
基础医学   808篇
口腔科学   596篇
临床医学   1486篇
内科学   2710篇
皮肤病学   396篇
神经病学   576篇
特种医学   660篇
外科学   1543篇
综合类   1584篇
现状与发展   1篇
预防医学   785篇
眼科学   161篇
药学   4092篇
  4篇
中国医学   240篇
肿瘤学   1237篇
  2024年   20篇
  2023年   200篇
  2022年   358篇
  2021年   575篇
  2020年   536篇
  2019年   558篇
  2018年   561篇
  2017年   548篇
  2016年   598篇
  2015年   631篇
  2014年   879篇
  2013年   1601篇
  2012年   884篇
  2011年   953篇
  2010年   739篇
  2009年   707篇
  2008年   711篇
  2007年   721篇
  2006年   582篇
  2005年   602篇
  2004年   487篇
  2003年   459篇
  2002年   382篇
  2001年   313篇
  2000年   266篇
  1999年   205篇
  1998年   183篇
  1997年   216篇
  1996年   140篇
  1995年   152篇
  1994年   127篇
  1993年   134篇
  1992年   115篇
  1991年   114篇
  1990年   92篇
  1989年   92篇
  1988年   91篇
  1987年   94篇
  1986年   73篇
  1985年   80篇
  1984年   79篇
  1983年   60篇
  1982年   57篇
  1981年   45篇
  1980年   44篇
  1979年   41篇
  1978年   38篇
  1977年   28篇
  1976年   32篇
  1973年   16篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Animal models and treatment of prostate cancer   总被引:1,自引:0,他引:1  
Model systems for prostate cancer in rats have been developed and used for investigations on tumor biology and therapy. The "Pollard tumors" provide a combination of in vitro and in vivo attributes by which investigations can be directed at local tumor development and spontaneous metastasis. The evolution and early applications of this model system are reviewed, and the therapeutic benefits of delayed release of cyclophosphamide are presented.  相似文献   
72.
《Value in health》2021,24(12):1828-1834
Antimicrobial resistance is a serious challenge to the success and sustainability of our healthcare systems. There has been increasing policy attention given to antimicrobial resistance in the last few years, and increased amounts of funding have been channeled into funding for research and development of antimicrobial agents. Nevertheless, manufacturers doubt whether there will be a market for new antimicrobial technologies sufficient to enable them to recoup their investment. Health technology assessment (HTA) has a critical role in creating confidence that if valuable technologies can be developed they will be reimbursed at a level that captures their true value. We identify 3 deficiencies of current HTA processes for appraising antimicrobial agents: a methods-centric approach rather than problem-centric approach for dealing with new challenges, a lack of tools for thinking about changing patterns of infection, and the absence of an approach to epidemiological risks. We argue that, to play their role more effectively, HTA agencies need to broaden their methodological tool kit, design and communicate their analysis to a wider set of users, and incorporate long-term policy goals, such as containing resistance, as part of their evaluation criteria alongside immediate health gains.  相似文献   
73.
74.
75.
76.
The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.  相似文献   
77.
Kidney transplant (KT) outcomes for HIV-infected (HIV+) persons are excellent, yet acute rejection (AR) is common and optimal immunosuppressive regimens remain unclear. Early steroid withdrawal (ESW) is associated with AR in other populations, but its utilization and impact are unknown in HIV+ KT. Using SRTR, we identified 1225 HIV+ KT recipients between January 1, 2000, and December 31, 2017, without AR, graft failure, or mortality during KT admission, and compared those with ESW with those with steroid continuation (SC). We quantified associations between ESW and AR using multivariable logistic regression and interval-censored survival analysis, as well as with graft failure and mortality using Cox regression, adjusting for donor, recipient, and immunologic factors. ESW utilization was 20.4%, with more zero HLA mismatch (8% vs 4%), living donors (26% vs 20%), and lymphodepleting induction (64% vs 46%) compared to the SC group. ESW utilization varied widely across 129 centers, with less use at high- versus moderate-volume centers (6% vs 21%, P < .001). AR was more common with ESW by 1 year (18.4% vs 12.3%; aOR: 1.081.612.41, P = .04) and over the study period (aHR: 1.021.391.90, P = .03), without difference in death-censored graft failure (aHR 0.600.911.36, P = .33) or mortality (aHR: 0.751.151.77, P = .45). To reduce AR after HIV+ KT, tailoring of ESW utilization is reasonable.  相似文献   
78.
Outcomes following hepatitis C virus (HCV)-viremic heart transplantation into HCV-negative recipients with HCV treatment are good. We assessed cost-effectiveness between cohorts of transplant recipients willing and unwilling to receive HCV-viremic hearts. Markov model simulated long-term outcomes among HCV-negative patients on the transplant waitlist. We compared costs (2018 USD) and health outcomes (quality-adjusted life-years, QALYs) between cohorts willing to accept any heart and those willing to accept only HCV-negative hearts. We assumed 4.9% HCV-viremic donor prevalence. Patients receiving HCV-viremic hearts were treated, assuming $39 600/treatment with 95% cure. Incremental cost-effectiveness ratios (ICERs) were compared to a $100 000/QALY gained willingness-to-pay threshold. Sensitivity analyses included stratification by blood type or region and potential negative consequences of receipt of HCV-viremic hearts. Compared to accepting only HCV-negative hearts, accepting any heart gained 0.14 life-years and 0.11 QALYs, while increasing costs by $9418/patient. Accepting any heart was cost effective (ICER $85 602/QALY gained). Results were robust to all transplant regions and blood types, except type AB. Accepting any heart remained cost effective provided posttransplant mortality and costs among those receiving HCV-viremic hearts were not >7% higher compared to HCV-negative hearts. Willingness to accept HCV-viremic hearts for transplantation into HCV-negative recipients is cost effective and improves clinical outcomes.  相似文献   
79.
Organ transplant recipients (OTRs) are at increased risk of cutaneous malignancy. Skin disorders in OTRs of color (OTRoC) have rarely been systematically assessed. We aimed to ascertain the burden of skin disease encountered in OTRoC by prospectively collecting data from OTRs attending 2 posttransplant skin surveillance clinics: 1 in London, UK and 1 in Philadelphia, USA. Retrospective review of all dermatological diagnoses was performed. Data from 1766 OTRs were analyzed: 1024 (58%) white, 376 (21%) black, 261 (15%) Asian, 57 (3%) Middle Eastern/Mediterranean (ME/M), and 48 (2.7%) Hispanic; and 1128 (64%) male. Viral infections affected 45.1% of OTRs, and were more common in white and ME/M patients (P < .001). Fungal infections affected 28.1% and were more common in ME/M patients (P < .001). Inflammatory skin disease affected 24.5%, and was most common in black patients (P < .001). In addition, 26.4% of patients developed skin cancer. There was an increased risk of skin cancer in white vs nonwhite OTRs (HR 4.4, 95% CI 3.5-5.7, P < .001): keratinocyte cancers were more common in white OTRs (P < .001) and Kaposi sarcoma was more common in black OTRs (P < .001). These data support the need for programs that promote targeted dermatology surveillance for all OTRs, regardless of race/ethnicity or country of origin.  相似文献   
80.
Desensitization has enabled incompatible living donor kidney transplantation (ILDKT) across HLA/ABO barriers, but added immunomodulation might put patients at increased risk of infections. We studied 475 recipients from our center from 2010 to 2015, categorized by desensitization intensity: none/compatible (n = 260), low (0-4 plasmaphereses, n = 47), moderate (5-9, n = 74), and high (≥10, n = 94). The 1-year cumulative incidence of infection was 50.1%, 49.8%, 66.0%, and 73.5% for recipients who received none, low, moderate, and high-intensity desensitization (P < .001). The most common infections were UTI (33.5% of ILDKT vs. 21.5% compatible), opportunistic (21.9% vs. 10.8%), and bloodstream (19.1% vs. 5.4%) (P < .001). In weighted models, a trend toward increased risk was seen in low (wIRR = 0.771.402.56,P = .3) and moderately (wIRR = 0.881.352.06,P = .2) desensitized recipients, with a statistically significant 2.22-fold (wIRR = 1.332.223.72,P = .002) increased risk in highly desensitized recipients. Recipients with ≥4 infections were at higher risk of prolonged hospitalization (wIRR = 2.623.574.88, P < .001) and death-censored graft loss (wHR = 1.154.0113.95,P = .03). Post–KT infections are more common in desensitized ILDKT recipients. A subset of highly desensitized patients is at ultra-high risk for infections. Strategies should be designed to protect patients from the morbidity of recurrent infections, and to extend the survival benefit of ILDKT across the spectrum of recipients.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号