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   16555篇
  免费   1212篇
  国内免费   74篇
耳鼻咽喉   277篇
儿科学   306篇
妇产科学   217篇
基础医学   2340篇
口腔科学   174篇
临床医学   1730篇
内科学   4224篇
皮肤病学   420篇
神经病学   1524篇
特种医学   714篇
外国民族医学   10篇
外科学   2482篇
综合类   59篇
一般理论   6篇
预防医学   774篇
眼科学   214篇
药学   1057篇
中国医学   15篇
肿瘤学   1298篇
  2023年   155篇
  2022年   235篇
  2021年   669篇
  2020年   354篇
  2019年   567篇
  2018年   672篇
  2017年   428篇
  2016年   499篇
  2015年   569篇
  2014年   757篇
  2013年   913篇
  2012年   1362篇
  2011年   1341篇
  2010年   731篇
  2009年   658篇
  2008年   1042篇
  2007年   1009篇
  2006年   873篇
  2005年   834篇
  2004年   706篇
  2003年   610篇
  2002年   552篇
  2001年   183篇
  2000年   169篇
  1999年   158篇
  1998年   113篇
  1997年   88篇
  1996年   82篇
  1995年   79篇
  1994年   65篇
  1993年   58篇
  1992年   109篇
  1991年   129篇
  1990年   116篇
  1989年   91篇
  1988年   70篇
  1987年   75篇
  1986年   82篇
  1985年   63篇
  1984年   70篇
  1983年   51篇
  1982年   62篇
  1981年   33篇
  1980年   27篇
  1979年   44篇
  1978年   38篇
  1977年   31篇
  1975年   23篇
  1974年   30篇
  1972年   23篇
排序方式: 共有10000条查询结果,搜索用时 687 毫秒
151.
The medicinally important quaternary ammonium salts benzyldimethyltetradecylammonium chloride (BDTA), cetylpyridinium chloride and benzethonium chloride, all afford, under fast atom bombardment (FAB) mass spectrometric conditions, abundant and persistent [M---Cl]+ species usefully amenable to quantitative analysis with the aid of thioglycerol as a liquid FAB matrix. The use of BDTA as an internal standard allowed a direct, precise and accurate determination of cetylpyridinium and benzethonium chlorides, either as pure samples or in dosage forms, in the concentration range 0.05–2 mg/ml.  相似文献   
152.
Despite magnesium (Mg2+) representing the second most abundant cation in the cell, its role in cellular physiology and pathology is far from being elucidated. Mg2+ homeostasis is regulated by Mg2+ transporters including Mitochondrial RNA Splicing Protein 2 (MRS2), Transient Receptor Potential Cation Channel Subfamily M, Member 6/7 (TRPM6/7), Magnesium Transporter 1 (MAGT1), Solute Carrier Family 41 Member 1 (SCL41A1), and Cyclin and CBS Domain Divalent Metal Cation Transport Mediator (CNNM) proteins. Recent data show that Mg2+ transporters may regulate several cancer cell hallmarks. In this review, we describe the expression of Mg2+ transporters in digestive cancers, the most common and deadliest malignancies worldwide. Moreover, Mg2+ transporters’ expression, correlation and impact on patient overall and disease-free survival is analyzed using Genotype Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) datasets. Finally, we discuss the role of these Mg2+ transporters in the regulation of cancer cell fates and oncogenic signaling pathways.  相似文献   
153.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Nach der Collectivity-of-Drinking-Cultures-Theorie von Skog finden Veränderungen des Alkoholkonsums in allen...  相似文献   
154.
We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds.  相似文献   
155.
有关医疗差错的报道经常占据报纸的显著位置。但却很少就其发生的可能性或原因进行评论 ,而是设想要是永远不发生该多好 !言外之意是差错越来越常见了。而事实如何呢 ?首先 ,差错总是会发生的。第二 ,虽然一项试验性研究首先尝试着对差错的多少进行量化1,但是未能明确显示在英国常见到何种地步。另外 ,如何表明差错的危险性大小也是一个难点。对于一个失去亲人的人来讲 ,危险性总是意味着百分之百 ,因此对他们说有千分之一的危险性也没有安慰作用。在一个每周将上百万美元花费在买彩票以求中奖的国家里 ,对于风险的概念明显不同。但可以明确…  相似文献   
156.
Purpose

This study aimed at reporting a head-to-head comparison between water vapor thermal therapy using the Rezūm? system and prostatic urethral lift using the Urolift? system in men with lower urinary tract symptoms due to benign prostatic hyperplasia (BPH).

Patients and methods

From December 2017 to November 2019, consecutive patients who underwent Rezūm? and Urolift? procedures in two urology centers have been retrospectively considered. Only patients with a prostate size less than 80 mL were included. We used the PSM method to adjust baseline differences between both groups. The co-primary endpoint included the change in International Prostate Symptom Score (IPSS) and IPSS- quality of life (QoL) from baseline to 12 months.

Results

A total of 61 (52.1%) and 56 (47.9%) patients underwent Rezum? and Urolift? procedures, respectively. After PSM adjustment, 24 patients were included in both groups. No serious adverse events occurred (>?Clavien II) in both groups. At 12 months, higher IPSS improvement was observed in the Rezum? group (median:4 [IQR 3–5]) than in the Urolift? group (median:8 [IQR 7–12]), without statistical difference (p?=?0.08). The improvement in term of QoL at 12 m was similar (p?=?0.43). The retreatment rates were 25% (Urolift?) and 8.3% (Rezum?), p?=?0.24. Erection and ejaculatory function scores did not change significantly in either treatment group. Results in the full cohort showed that Rezum? appeared to deliver greater improvements for IPSS and IPSS-QoL (p?<?0.001 and p?=?0.006, respectively) and lower reintervention rate (p?=?0.006) than Urolift?.

Conclusions

In this small retrospective study, our results indicate that both Rezum? and Urolift? provide a clinically significant improvement in symptoms and QoL, although some of these improvements were greater in the Rezum? arm. Future studies are needed to definitively assess which treatment would be best suited for each patient.

  相似文献   
157.
BackgroundMicrobial contamination of human skin allografts is a frequent cause of allograft discard. Our purpose was to evaluate the discard rate of skin bank contaminated allografts and specific procedures used to reduce allograft contamination without affecting safety.MethodsWe conducted at the Lille Tissue Bank a retrospective study of all deceased donors (n = 104) harvested from January 2018 to December 2018. Skin procurement was split into 3 zones: the back of the body and the two legs that were processed separately. It represented 433 cryopreserved skin allograft pouches of approximatively 500 cm² each. Donors were almost equally split between brain-dead (53%, 55/104) and cadaveric (47%, 49/104) donors.ResultsOut of all donors, 42 (40.5%) had at least one sampling zone with a positive microbiological test resulting in 106 (24%) contaminated skin pouches. The contamination rate did not vary according to the harvested zone or type of donor. Traumatic deaths showed significantly less contamination rates than other death types (p < 0.05). Contamination rate decreased with time spent in the antibiotic solution. The risk of having contaminated allografts was five-fold higher when the skin spent less than 96 h in the antibiotic cocktail (p < 0.05). According to our validation protocol, most donors (32/42, 76%) had skin allografts contaminated with bacteria (mainly Staphylococcus spp) compatible with clinical use. No recipient infection was recorded as a result of skin graft contaminated with saprophytic or non-pathogenic germs. By harvesting 3 separate zones per donor, the total surface area for clinical use increased by 53% for contaminated donors. Overall, the proportion of contamination-related discarded allografts was 3.2% (14/433 of pouches).ConclusionFew simple pragmatic measures (including skin incubation in the antibiotic bath for at least 96 h at 4 °C, splitting the skin harvesting areas to minimize the risk of cross-infection and clinical use of allografts contaminated with saprophytic and non-pathogenic germs) can reduce the discard rate of contaminated allografts without affecting clinical safety.  相似文献   
158.
Neurosurgical Review - Trigeminal nerve schwannomas (TS) are uncommon intracranial tumors, frequently presenting with debilitating trigeminal and/or oculomotor nerve dysfunction. While surgical...  相似文献   
159.
160.
BackgroundWeb-based platforms used to enhance patient-provider communication are being explored to improve patient satisfaction and care delivery, and decrease cost. This study tested a web-based interactive patient-provider software platform (IPSP), JointCOACH, which enabled patient communication with their care team and preparatory/recovery guidance. The aims of this study are to compare (1) patient satisfaction and (2) healthcare resource utilization by patients who underwent total knee and hip replacements and added IPSP to standard of care (SOC).MethodsThis study is a prospective, randomized clinical trial at a single large academic healthcare system. Between May 2018 and March 2020, 399 patients undergoing elective total hip or knee arthroplasty were randomized to SOC arm (n = 204) or SOC + IPSP arm (n = 195). Patient demographics, surgical details, and comorbidities were collected. Patient satisfaction was assessed using Visual Analog Scale and the Picker Patient Experience-15. Healthcare utilization was measured using length of stay, emergency department and office visits, office calls, readmissions, and reoperations at 30 and 90 days after surgery.ResultsNo difference was found in length of stay between SOC and SOC + IPSP. No differences were found in 30-day or 90-day satisfaction or in healthcare resource utilization (P > .05) including number of office and emergency department visits, phone calls, and readmissions.ConclusionStatistical differences were not found in satisfaction and healthcare utilization with the addition of IPSP to SOC. IPSP can be used to reinforce patient education and communication between the patient and provider, and should be evaluated as an element of virtual care rather than supplementing traditional in-office follow-up.Clinicaltrials.govMore information on this study can be found at clinicaltrials.gov NCT03499028.  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