全文获取类型
收费全文 | 2371757篇 |
免费 | 198180篇 |
国内免费 | 4204篇 |
专业分类
耳鼻咽喉 | 34264篇 |
儿科学 | 72747篇 |
妇产科学 | 62933篇 |
基础医学 | 334881篇 |
口腔科学 | 67520篇 |
临床医学 | 215529篇 |
内科学 | 468710篇 |
皮肤病学 | 47929篇 |
神经病学 | 200795篇 |
特种医学 | 95967篇 |
外国民族医学 | 886篇 |
外科学 | 360402篇 |
综合类 | 56217篇 |
现状与发展 | 1篇 |
一般理论 | 977篇 |
预防医学 | 190616篇 |
眼科学 | 55469篇 |
药学 | 177538篇 |
4篇 | |
中国医学 | 4365篇 |
肿瘤学 | 126391篇 |
出版年
2018年 | 24207篇 |
2016年 | 20575篇 |
2015年 | 23280篇 |
2014年 | 33538篇 |
2013年 | 50829篇 |
2012年 | 68737篇 |
2011年 | 72286篇 |
2010年 | 42472篇 |
2009年 | 40863篇 |
2008年 | 68759篇 |
2007年 | 73096篇 |
2006年 | 73994篇 |
2005年 | 72036篇 |
2004年 | 69335篇 |
2003年 | 67014篇 |
2002年 | 66269篇 |
2001年 | 112456篇 |
2000年 | 116531篇 |
1999年 | 98339篇 |
1998年 | 27862篇 |
1997年 | 25525篇 |
1996年 | 25451篇 |
1995年 | 24614篇 |
1994年 | 23165篇 |
1993年 | 21554篇 |
1992年 | 79391篇 |
1991年 | 76397篇 |
1990年 | 73579篇 |
1989年 | 70855篇 |
1988年 | 65862篇 |
1987年 | 64816篇 |
1986年 | 61350篇 |
1985年 | 58415篇 |
1984年 | 44238篇 |
1983年 | 37668篇 |
1982年 | 22888篇 |
1981年 | 20337篇 |
1980年 | 19036篇 |
1979年 | 41309篇 |
1978年 | 29003篇 |
1977年 | 24351篇 |
1976年 | 22837篇 |
1975年 | 23967篇 |
1974年 | 29640篇 |
1973年 | 28042篇 |
1972年 | 26227篇 |
1971年 | 24155篇 |
1970年 | 22752篇 |
1969年 | 21091篇 |
1968年 | 19139篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
171.
Few studies have examined the effects of parental incarceration (PI) on outcomes above and beyond other risk and adverse childhood experiences (ACEs). The objectives of this study were to (1) the associations between PI and mental health problems (attention, externalizing, internalizing, and total behavioral problems) and (2) the mediating role of current socioeconomic status and cumulative ACEs. An observational and cross-sectional design was employed. Analyses included hierarchical multivariable linear regression modeling. The analytic sample included 613 adolescents (11–17?years). On average, youth exposed to PI experienced three times as many ACEs compared with youth unexposed. Youth exposed to PI were more likely to have behavioral problems than their unexposed peers. The main effect for all models was attenuated by current economic hardship as well as exposure to increasing numbers of ACEs. Exposure to PI can be viewed as a marker of accumulative risk for intervention since youth impacted by PI are more likely to experience behavioral difficulties and associated adverse childhood experiences. Due to the associated adversity that impact youth exposed to PI, mental health providers need to be able to identify and screen for symptoms associated with trauma. 相似文献
172.
Anastasiia Panfilova Sarah E. Shelton Cristina Caresio Ruud J.G. van Sloun Filippo Molinari Hessel Wijkstra Paul A. Dayton Massimo Mischi 《Ultrasound in medicine & biology》2019,45(2):539-548
Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA. 相似文献
173.
O.R. Mitchell R. Dave J. Bekker P.A. Brennan 《The British journal of oral & maxillofacial surgery》2021,59(3):384-385
The first COVID-19 vaccination was given in December 2020 and there is an effort to vaccinate the international population on a massive scale. Common side effects from the vaccine include headache and tiredness. Regional lymphadenopathy has been described in relation to other vaccines. We describe two cases of supraclavicular reactive lymphadenopathy presenting in patients who had the COVID vaccination in the ipsilateral arm. Awareness of this diagnosis is important for patients presenting to the neck lump clinic. 相似文献
174.
Mariano E. Menendez Suleiman Y. Sudah Patrick J. Denard 《Seminars in Arthroplasty》2022,32(3):644-649
BackgroundThe growing enthusiasm for the use of reverse shoulder arthroplasty (RSA) in the treatment of primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff is based on data derived from single-center studies with limited generalizability and follow-up. This study compared patient-reported outcomes (PROs) between RSA and total shoulder arthroplasty (TSA) for the treatment of primary GHOA with up to 5-year follow-up and examined temporal trends in the treatment of GHOA between 2012 and 2021.MethodsA retrospective review was performed on patients with primary GHOA undergoing primary arthroplasty surgery from the Surgical Outcomes System global registry between 2012 and 2021. PROs including the American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE) score, and visual analog scale (VAS) for pain were compared between RSA and TSA at 1, 2, and 5 years postoperatively.ResultsA total of 4451 patients were included, with 2693 (60.5%) undergoing TSA and 1758 (39.5%) undergoing RSA. Both RSA and TSA provided clinically excellent outcomes at 1 year postoperatively (ASES: 80.8 ± 17.9 vs. 85.9 ± 15.2, respectively; SANE: 74.8 ± 24.7 vs. 79.5 ± 22.9; VAS pain: 1.3 ± 2.0 vs. 1.1 ± 1.7; all P < .05) that were maintained at 2 years (ASES: 81.3 ± 19.3 vs. 87.3 ± 14.9; SANE: 74.8 ± 26.2 vs. 79.7 ± 24.7; VAS pain: 1.3 ± 2.1 vs. 1.0 ± 1.6; all P < .05) and 5 years (ASES: 81.7 ± 16.5 vs. 86.9 ± 15.3; SANE: 71.6 ± 28.5 vs. 78.2 ± 25.9; VAS pain: 1.0 ± 1.7 vs. 1.0 ± 1.7; all P < .05), with statistical significance favoring TSA. After controlling for age and sex, there was an adjusted difference of 4.5 units in the ASES score favoring TSA (P = .005) at 5 years postoperatively but no differences in adjusted SANE (P = .745) and VAS pain (P = .332) scores. The use of RSA for GHOA grew considerably over time, from representing only 17% of all replacements performed for GHOA in 2012 to nearly half (47%) in 2021 (P < .001).ConclusionRSA as a treatment for GHOA with an intact rotator cuff seems to yield PROs that are largely clinically equivalent to TSA extending to 5 years postoperatively. The observed statistical significance favoring TSA appears to be of marginal clinical benefit based on established minimal clinically important differences and may be a result of the large sample size. Further research using more granular clinical data and examining differences in range of motion and complications is warranted as it may change the value analysis. 相似文献
175.
Bielik Peter Bonczek Ondřej Krejčí Přemysl Zeman Tomáš Izakovičová-Hollá Lydie Šoukalová Jana Vaněk Jiří Vojtěšek Bořivoj Lochman Jan Balcar Vladimir J. Šerý Omar 《Clinical oral investigations》2022,26(12):7045-7055
Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of... 相似文献
176.
177.
Accurate diagnosis and recognition of predisposing factors has been shown to be challenging in lower limb cellulitis (LLC). Assessment of 1746 consecutive patients with cellulitis presenting to a UK university hospital showed increasing overdiagnosis, with only 31.9% of patients referred during the period 2015–2018 having the diagnosis of LLC confirmed. Recognition of at least one predisposing factor increased from 61% to 89% following introduction of more specific screening questions. This identified a need for better primary care dermatology education and the benefit of a proforma with specific screening questions for reversible predisposing factors for LLC. 相似文献
178.
179.