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   25875篇
  免费   1845篇
  国内免费   157篇
耳鼻咽喉   90篇
儿科学   1473篇
妇产科学   609篇
基础医学   2244篇
口腔科学   109篇
临床医学   2525篇
内科学   7844篇
皮肤病学   463篇
神经病学   2021篇
特种医学   251篇
外科学   3085篇
综合类   619篇
一般理论   7篇
预防医学   2205篇
眼科学   952篇
药学   1132篇
  1篇
中国医学   55篇
肿瘤学   2192篇
  2024年   11篇
  2023年   243篇
  2022年   121篇
  2021年   299篇
  2020年   340篇
  2019年   121篇
  2018年   461篇
  2017年   502篇
  2016年   550篇
  2015年   538篇
  2014年   457篇
  2013年   722篇
  2012年   2041篇
  2011年   2297篇
  2010年   801篇
  2009年   777篇
  2008年   2443篇
  2007年   2349篇
  2006年   2023篇
  2005年   2114篇
  2004年   2091篇
  2003年   2104篇
  2002年   1687篇
  2001年   1259篇
  2000年   292篇
  1999年   149篇
  1998年   203篇
  1997年   125篇
  1996年   95篇
  1995年   64篇
  1994年   76篇
  1993年   39篇
  1992年   47篇
  1991年   38篇
  1990年   43篇
  1989年   40篇
  1988年   42篇
  1987年   40篇
  1986年   34篇
  1985年   31篇
  1984年   30篇
  1983年   17篇
  1982年   18篇
  1981年   24篇
  1980年   12篇
  1979年   9篇
  1978年   8篇
  1977年   5篇
  1974年   6篇
  1970年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
The Earth’s mean surface temperature is already approximately 1.1°C higher than pre-industrial levels. Exceeding a mean 1.5°C rise by 2050 will make global adaptation to the consequences of climate change less possible. To protect public health, anaesthesia providers need to reduce the contribution their practice makes to global warming. We convened a Working Group of 45 anaesthesia providers with a recognised interest in sustainability, and used a three-stage modified Delphi consensus process to agree on principles of environmentally sustainable anaesthesia that are achievable worldwide. The Working Group agreed on the following three important underlying statements: patient safety should not be compromised by sustainable anaesthetic practices; high-, middle- and low-income countries should support each other appropriately in delivering sustainable healthcare (including anaesthesia); and healthcare systems should be mandated to reduce their contribution to global warming. We set out seven fundamental principles to guide anaesthesia providers in the move to environmentally sustainable practice, including: choice of medications and equipment; minimising waste and overuse of resources; and addressing environmental sustainability in anaesthetists’ education, research, quality improvement and local healthcare leadership activities. These changes are achievable with minimal material resource and financial investment, and should undergo re-evaluation and updates as better evidence is published. This paper discusses each principle individually, and directs readers towards further important references.  相似文献   
2.
【摘要】 介入手术后医院感染严重危害人类健康。制定介入手术室医院感染控制和预防临床实践专家共识可更好地规范介入手术过程中相关临床实践标准,降低医院感染发生率。本共识基于 WHO指南制定手册和GRADE证据质量分级系统,形成了介入手术室环境管理、患者管理、工作人员管理、物品管理、职业暴露、培训与质量控制等6个领域54项推荐意见,供相关人员参考。  相似文献   
3.
4.
Evidence exists that women and people from low- and middle-income countries are under-represented on the editorial boards of medical journals. This may adversely influence the journal output. We conducted a pooled, cross-sectional evaluation of the editorial board membership of anaesthesia journals. We collected data on members of editorial boards from the founding year and at 5-yearly intervals until 2020. For each editor, we recorded gender, country of affiliation, World Bank income classification (1990 onwards) and editorial role (2020 only). The composite editorial board diversity score was calculated for each editorial board. We obtained complete data for the composition of editorial boards from all 30 journals for 2020, but for only 171 out of 304 editorial boards (56%) over the time period examined. In 2020, 409 out of 1973 (21%) were women (range across the editorial boards 0–39%) and 139 out of 1982 (7%) were from low-, low-middle- and upper-middle-income countries (range across the editorial boards 0–71%). In 2020, of editorial board positions with known seniority status, 109 out of 259 (42%) of women and 306 out of 960 (32%) of men were in senior roles. In the same year, 397 out of 1115 (36%) of people from high-income countries were in senior roles, compared with 19 out of 93 (20%) of people from upper-middle-income countries and 0 out of 14 (0%) people from lower-middle-income countries. The median composite editorial board diversity score was 4 (range 2–6) in 2020 – 5 or less suggests poor diversity, while 8 or more suggests good diversity. Women and people from low- and middle-income countries are under-represented on anaesthesia journal editorial boards. The editorial boards do not reflect the anaesthesia workforce and may act as a barrier to the publication of research produced by these groups. Urgent action is required to improve diversity.  相似文献   
5.
Since the start of the COVID-19 pandemic, few studies have reported anaesthetic outcomes in parturients with SARS-CoV-2 infection. We reviewed the labour analgesic and anaesthetic interventions utilised in symptomatic and asymptomatic parturients who had a confirmed positive test for SARS-CoV-2 across 10 hospitals in the north-west of England between 1 April 2020 and 31 May 2021. Primary outcomes analysed included the analgesic/anaesthetic technique utilised for labour and caesarean birth. Secondary outcomes included a comparison of maternal characteristics, caesarean birth rate, maternal critical care admission rate along with adverse composite neonatal outcomes. A positive SARS-CoV-2 test was recorded in 836 parturients with 263 (31.4%) reported to have symptoms of COVID-19. Neuraxial labour analgesia was utilised in 104 (20.4%) of the 509 parturients who went on to have a vaginal birth. No differences in epidural analgesia rates were observed between symptomatic and asymptomatic parturients (OR 1.03, 95%CI 0.64–1.67; p = 0.90). The neuraxial anaesthesia rate in 310 parturients who underwent caesarean delivery was 94.2% (95%CI 90.6–96.0%). The rates of general anaesthesia were similar in symptomatic and asymptomatic parturients (6% vs. 5.7%; p = 0.52). Symptomatic parturients were more likely to be multiparous (OR 1.64, 95%CI 1.19–2.22; p = 0.002); of Asian ethnicity (OR 1.54, 1.04–2.28; p = 0.03); to deliver prematurely (OR 2.16, 95%CI 1.47–3.19; p = 0.001); have a higher caesarean birth rate (44.5% vs. 33.7%; OR 1.57, 95%CI 1.16–2.12; p = 0.008); and a higher critical care utilisation rate both pre- (8% vs. 0%, p = 0.001) and post-delivery (11% vs. 3.5%; OR 3.43, 95%CI 1.83–6.52; p = 0.001). Eight neonates tested positive for SARS-CoV-2 while no differences in adverse composite neonatal outcomes were observed between those born to symptomatic and asymptomatic mothers (25.8% vs. 23.8%; OR 1.11, 95%CI 0.78–1.57; p = 0.55). In women with COVID-19, non-neuraxial analgesic regimens were commonly utilised for labour while neuraxial anaesthesia was employed for the majority of caesarean births. Symptomatic women with COVID-19 are at increased risk of significant maternal morbidity including preterm birth, caesarean birth and peripartum critical care admission.  相似文献   
6.
7.
8.
Non-clear cell renal cell carcinoma is a very rare malignancy that includes several histological subtypes. Each subtype may need to be addressed separately regarding prognosis and treatment; however, no Phase III clinical trial data exist. Thus, treatment recommendations for patients with non-clear cell metastatic RCC (mRCC) remain unclear. We present first prospective data on choice of first- and second-line treatment in routine practice and outcome of patients with papillary mRCC. From the prospective German clinical cohort study (RCC-Registry), 99 patients with papillary mRCC treated with systemic first-line therapy between December 2007 and May 2017 were included. Prospectively enrolled patients who had started first-line treatment until May 15, 2016, were included into the outcome analyses (n = 82). Treatment was similar to therapies used for clear cell mRCC and consisted of tyrosine kinase inhibitors, mechanistic target of rapamycin inhibitors and recently checkpoint inhibitors. Median progression-free survival from start of first-line treatment was 5.4 months (95% confidence interval [CI], 4.1–9.2) and median overall survival was 12.0 months (95% CI, 8.1–20.0). At data cutoff, 73% of the patients died, 6% were still observed, 12% were lost to follow-up, and 9% were alive at the end of the individual 3-year observation period. Despite the lack of prospective Phase III evidence in patients with papillary mRCC, our real-world data reveal effectiveness of systemic clear cell mRCC therapy in papillary mRCC. The prognosis seems to be inferior for papillary compared to clear cell mRCC. Further studies are needed to identify drivers of effectiveness of systemic therapy for papillary mRCC.  相似文献   
9.
The prevalence of Lynch syndrome (LS) varies significantly in different populations, suggesting that ethnic features might play an important role. We enrolled 3330 consecutive Chinese patients who had surgical resection for newly diagnosed colorectal cancer. Universal screening for LS was implemented, including immunohistochemistry for mismatch repair (MMR) proteins, BRAFV600E mutation test and germline sequencing. Among the 3250 eligible patients, MMR protein deficiency (dMMR) was detected in 330 (10.2%) patients. Ninety-three patients (2.9%) were diagnosed with LS. Nine (9.7%) patients with LS fulfilled Amsterdam criteria II and 76 (81.7%) met the revised Bethesda guidelines. Only 15 (9.7%) patients with absence of MLH1 on IHC had BRAFV600E mutation. One third (33/99) of the MMR gene mutations have not been reported previously. The age of onset indicates risk of LS in patients with dMMR tumors. For patients older than 65 years, only 2 patients (5.7%) fulfilling revised Bethesda guidelines were diagnosed with LS. Selective sequencing of all cases with dMMR diagnosed at or below age 65 years and only of those dMMR cases older than 65 years who fulfill revised Bethesda guidelines results in 8.2% fewer cases requiring germline testing without missing any LS diagnoses. While the prevalence of LS in Chinese patients is similar to that of Western populations, the spectrum of constitutional mutations and frequency of BRAFV600E mutation is different. Patients older than 65 years who do not meet the revised Bethesda guidelines have a low risk of LS, suggesting germline sequencing might not be necessary in this population.  相似文献   
10.
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