全文获取类型
收费全文 | 63725篇 |
免费 | 7661篇 |
国内免费 | 1128篇 |
专业分类
耳鼻咽喉 | 390篇 |
儿科学 | 1953篇 |
妇产科学 | 1299篇 |
基础医学 | 3610篇 |
口腔科学 | 1775篇 |
临床医学 | 9777篇 |
内科学 | 11987篇 |
皮肤病学 | 626篇 |
神经病学 | 4869篇 |
特种医学 | 1249篇 |
外国民族医学 | 1篇 |
外科学 | 6321篇 |
综合类 | 5540篇 |
现状与发展 | 8篇 |
一般理论 | 15篇 |
预防医学 | 12232篇 |
眼科学 | 773篇 |
药学 | 4970篇 |
87篇 | |
中国医学 | 716篇 |
肿瘤学 | 4316篇 |
出版年
2024年 | 149篇 |
2023年 | 1628篇 |
2022年 | 2186篇 |
2021年 | 3832篇 |
2020年 | 3646篇 |
2019年 | 3499篇 |
2018年 | 3437篇 |
2017年 | 3202篇 |
2016年 | 3124篇 |
2015年 | 2784篇 |
2014年 | 4940篇 |
2013年 | 6259篇 |
2012年 | 3535篇 |
2011年 | 3860篇 |
2010年 | 2892篇 |
2009年 | 2861篇 |
2008年 | 2887篇 |
2007年 | 2655篇 |
2006年 | 2277篇 |
2005年 | 2028篇 |
2004年 | 1634篇 |
2003年 | 1366篇 |
2002年 | 1167篇 |
2001年 | 1070篇 |
2000年 | 816篇 |
1999年 | 669篇 |
1998年 | 603篇 |
1997年 | 509篇 |
1996年 | 432篇 |
1995年 | 382篇 |
1994年 | 345篇 |
1993年 | 308篇 |
1992年 | 253篇 |
1991年 | 208篇 |
1990年 | 161篇 |
1989年 | 144篇 |
1988年 | 120篇 |
1987年 | 103篇 |
1986年 | 87篇 |
1985年 | 117篇 |
1984年 | 89篇 |
1983年 | 40篇 |
1982年 | 59篇 |
1981年 | 43篇 |
1980年 | 34篇 |
1979年 | 24篇 |
1978年 | 10篇 |
1977年 | 11篇 |
1975年 | 8篇 |
1974年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
Yasmine Yousef Etienne St-Louis Robert Baird Emily R. Smith Elena Guadagno Dickens St-Vil Dan Poenaru 《Journal of pediatric surgery》2019,54(4):831-837
Background
The Lancet Commission on Global Surgery highlighted global surgical need but offered little insight into the specific surgical challenges of children in low-resource settings. Efforts to strengthen the quality of global pediatric surgical care have resulted in a proliferation of partnerships between low-and middle-income countries (LMICs) and high-income countries (HICs). Standardized tools able to reliably measure gaps in delivery and quality of care are important aids for these partnerships. We undertook a systematic review (SR) of capacity assessment tools (CATs) focused on needs assessment in pediatric surgery.Methods
A comprehensive search strategy of multiple electronic databases was conducted per PRISMA guidelines without linguistic or temporal restrictions. CATs were selected according to pre-defined inclusion criteria. Articles were assessed by two independent reviewers. Methodological quality of studies was appraised using the COSMIN checklist with 4-point scale.Results
The search strategy generated 16,641 original publications, of which three CATs were deemed eligible. Eligible tools were either excessively detailed or oversimplified. None used weighted scores to identify finer granularity between institutions. No CATs comprehensively included measures of resources, outcomes, accessibility/impact and training.Discussion
The results of this study identify the need for a CAT capable of objectively measuring key aspects of surgical capacity and performance in a weighted tool designed for pediatric surgical centers in LMICs.Type of Study
Systematic Review.Level of Evidence
II. 相似文献43.
44.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(10):1030-1039
Background and aimThis network meta-analysis (NMA) compares the effects of different types of olive oil (OO) on cardiovascular risk factors.Methods and resultsLiterature search was conducted on three electronic databases (Medline, Web of Science, and Cochrane Central). Inclusion criteria: Randomized controlled trials (RCTs) (≥3 weeks duration of intervention) comparing at least two of the following types of OO: refined OO (ROO), mixed OO (MOO), low phenolic (extra) virgin OO (LP(E)VOO), and high phenolic (extra) virgin OO (HP(E)VOO). Random-effects NMA was performed for seven outcomes; and surface under the cumulative ranking curve (SUCRA) was estimated, using an analytical approach (P-score). Thirteen RCTs (16 reports) with 611 mainly healthy participants (mean age: 26–70 years) were identified. No differences for total cholesterol, HDL-cholesterol, triacylglycerols, and diastolic blood pressure were observed comparing ROO, MOO, LP(E)VOO and HP(E)VOO. HP(E)VOO slightly reduce LDL-cholesterol (LDL-C) compared to LP(E)VOO (mean difference [MD]: −0.14 mmol/L, 95%–CI: −0.28, −0.01). Both, HP(E)VOO and LP(E)VOO reduces SBP compared to ROO (range of MD: −2.99 to −2.87 mmHg), and HP(E)VOO may improve oxidized LDL-cholesterol (oxLDL-C) compared to ROO (standardized MD: −0.68, 95%–CI: −1.31, −0.04). In secondary analyses, EVOO may reduce oxLDL-C compared to ROO, and a dose-response relationship between higher intakes of phenolic compounds from OO and lower SBP and oxLDL-C values was detected. HP(E)VOO was ranked as best treatment for LDL-C (P-score: 0.83), oxLDL-C (0.88), and SBP (0.75).ConclusionsHP(E)VOO may improve some cardiovascular risk factors, however, public health implications are limited by overall low or moderate certainty of evidence. 相似文献
45.
BackgroundHeavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as μg/g wet weight.ResultsHeavy metal concentrations in muscle ranged between:(0.054–0.109), (0.260–1.043), (0.264–0.897), (5.895–11.898), (0.381–0.970), (13.582–29.133) and (0.332–0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1.ConclusionThis study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks. 相似文献
46.
《Annals of hepatology》2019,18(4):563-570
Introduction and ObjectivesNonalcoholic fatty liver disease (NAFLD) can be considered one of the most common causes of liver disease in our days and is regarded as one of the newest vascular risk factors for cerebrovascular and other neurological diseases.Materials and methodsWe studied a group of neurological outpatients, divided into two homogenous groups based on the presence or absence of NAFLD.Results and conclusionsWe testified an independent relationship between NAFLD and common vascular risk factors (age, sex, educational level, BMI, cholesterol and lipid assessment, Hb1ac). At the same time, we ascertained an independent relationship between NAFLD and more recently recognized vascular risk factors, such as lack of folate, vitamin B12 and vitamin D-OH25, and increased levels of homocysteine. Finally, we have documented that NAFLD showed worse executive and frontal functions, and behavioral changes, such as depressive mood and anxiety, and apathy. 相似文献
47.
Julia H. Vermylen Gordon J. Wood Elaine R. Cohen Jeffrey H. Barsuk William C. McGaghie Diane B. Wayne 《Journal of pain and symptom management》2019,57(3):682-687
Introduction
Physician communication impacts patient outcomes. However, communication skills, especially around difficult conversations, remain suboptimal, and there is no clear way to determine the validity of entrustment decisions. The aims of this study were to 1) describe the development of a simulation-based mastery learning (SBML) curriculum for breaking bad news (BBN) conversation skills and 2) set a defensible minimum passing standard (MPS) to ensure uniform skill acquisition among learners.Innovation
An SBML BBN curriculum was developed for fourth-year medical students. An assessment tool was created to evaluate the acquisition of skills involved in a BBN conversation. Pilot testing was completed to confirm improvement in skill acquisition and set the MPS.Outcomes
A BBN assessment tool containing a 15-item checklist and six scaled items was developed. Students' checklist performance improved significantly at post-test compared to baseline (mean 65.33%, SD = 12.09% vs mean 88.67%, SD = 9.45%, P < 0.001). Students were also significantly more likely to have at least a score of 4 (on a five-point scale) for the six scaled questions at post-test. The MPS was set at 80%, requiring a score of 12 items on the checklist and at least 4 of 5 for each scaled item. Using the MPS, 30% of students would require additional training after post-testing.Comments
We developed a SBML curriculum with a comprehensive assessment of BBN skills and a defensible competency standard. Future efforts will expand the mastery model to larger cohorts and assess the impact of rigorous education on patient care outcomes. 相似文献48.
49.
目的:探讨早产儿消化道穿孔的病因,分析影响早产儿消化道穿孔短期预后不良的危险因素。方法:回顾性分析山西省
儿童医院新生儿外科2015年1月—2021 年5月诊治的89 例早产儿消化道穿孔的临床资料。根据术后3 个月时结局分为生存
组和预后不良组。比较两组术前、术中及术后与早产儿消化道穿孔预后不良相关的因素,采用Logistic 回归分析筛选早产儿消
化道穿孔预后不良的危险因素。结果:早产儿消化道穿孔的病死率为25.84%,坏死性小肠结肠炎(NEC)和胃壁肌层缺损是早产
儿消化道穿孔常见的病因。单因素分析显示生存组患儿从发现气腹至手术时间在8 h 之内的比例显著高于预后不良组
(χ2=15.22,P<0.01)。预后不良组合并脓毒性休克的比例显著高于生存组(χ2=33.19,P<0.01)。预后不良组术后合并需非计划二次
手术的并发症比例显著高于生存组(χ2=7.24,P<0.01)。Logistic 回归分析显示脓毒性休克(OR=0.06,95%CI:0.02~0.21,P<0.01)和
气腹至手术时间大于8 h(OR=0.23,95%CI:0.07~0.81,P<0.05)是早产儿消化道穿孔短期预后不良的危险因素。结论:NEC 和胃
壁肌层缺损是早产儿消化道穿孔的主要病因,脓毒性休克和从气腹发生至手术时间大于8 h 是早产儿消化道穿孔短期预后
不良的危险因素。 相似文献
50.
《Value in health》2022,25(12):1958-1966
ObjectivesNational health technology assessments (HTAs) across Europe show differences in evidentiary requirements from assessments by the European Medicines Agency (EMA), affecting time to patient access for drugs after marketing authorization. This article analyzes the differences between EMA and HTA bodies’ evidentiary requirements for oncology drugs and provides recommendations on potential further alignment to minimize and optimally manage the remaining differences.MethodsInterviews were performed with representatives and drug assessment experts from EMA and HTA bodies to identify evidentiary requirements for several subdomains and collect recommendations for potentially more efficiently addressing differences. A comparative analysis of acceptability of the evidence by EMA and the HTA bodies and for potential further alignment between both authorities was conducted.ResultsAcceptability of available evidence was higher for EMA than HTA bodies. HTA bodies and EMA were aligned on evidentiary requirements in most cases. The subdomains showing notable differences concerned the acceptance of limitation of the target population and extrapolation of target populations, progression-free survival and (other) surrogate endpoints as outcomes, cross-over designs, short trial duration, and clinical relevance of the effect size. Recommendations for reducing or optimally managing differences included joint early dialogues, joint relative effectiveness assessments, and the use of managed entry agreements.ConclusionsDifferences between assessments of EMA and HTA bodies were identified in important areas of evidentiary requirements. Increased alignment between EMA and HTA bodies is suggested and recommendations for realization are discussed. 相似文献