全文获取类型
收费全文 | 311899篇 |
免费 | 23268篇 |
国内免费 | 1131篇 |
专业分类
耳鼻咽喉 | 3624篇 |
儿科学 | 8337篇 |
妇产科学 | 6115篇 |
基础医学 | 40435篇 |
口腔科学 | 6283篇 |
临床医学 | 33638篇 |
内科学 | 62953篇 |
皮肤病学 | 4458篇 |
神经病学 | 29913篇 |
特种医学 | 12714篇 |
外国民族医学 | 23篇 |
外科学 | 47563篇 |
综合类 | 4153篇 |
现状与发展 | 1篇 |
一般理论 | 239篇 |
预防医学 | 25536篇 |
眼科学 | 7307篇 |
药学 | 21859篇 |
2篇 | |
中国医学 | 394篇 |
肿瘤学 | 20751篇 |
出版年
2023年 | 1494篇 |
2022年 | 2271篇 |
2021年 | 6335篇 |
2020年 | 3712篇 |
2019年 | 6058篇 |
2018年 | 7293篇 |
2017年 | 5361篇 |
2016年 | 5847篇 |
2015年 | 6864篇 |
2014年 | 9813篇 |
2013年 | 13561篇 |
2012年 | 20400篇 |
2011年 | 21362篇 |
2010年 | 11850篇 |
2009年 | 11040篇 |
2008年 | 18788篇 |
2007年 | 19855篇 |
2006年 | 19274篇 |
2005年 | 19158篇 |
2004年 | 18033篇 |
2003年 | 16526篇 |
2002年 | 15873篇 |
2001年 | 4607篇 |
2000年 | 4229篇 |
1999年 | 4457篇 |
1998年 | 3793篇 |
1997年 | 3042篇 |
1996年 | 2742篇 |
1995年 | 2508篇 |
1994年 | 2288篇 |
1993年 | 2202篇 |
1992年 | 3058篇 |
1991年 | 2927篇 |
1990年 | 2662篇 |
1989年 | 2585篇 |
1988年 | 2428篇 |
1987年 | 2375篇 |
1986年 | 2309篇 |
1985年 | 2330篇 |
1984年 | 2276篇 |
1983年 | 2032篇 |
1982年 | 1849篇 |
1981年 | 1658篇 |
1980年 | 1451篇 |
1979年 | 1672篇 |
1978年 | 1381篇 |
1977年 | 1199篇 |
1976年 | 1119篇 |
1975年 | 1023篇 |
1974年 | 1167篇 |
排序方式: 共有10000条查询结果,搜索用时 756 毫秒
41.
William G. Breen Krishan R. Jethwa Nathan Y. Yu Grant M. Spears William S. Harmsen Robert C. Miller Jonathan B. Ashman William G. Rule Terence T. Sio Michelle A. Neben-Wittich Michael G. Haddock Amit Mahipal Mark J. Truty Christopher L. Hallemeier Kenneth W. Merrell 《Practical radiation oncology》2021,11(1):e63-e69
PurposeOur purpose was to determine the effect of chemoradiotherapy (CRT) on patient-reported quality of life (QOL) for patients with intact pancreas cancer.Methods and MaterialsWe reviewed a prospective QOL registry for patients with intact, clinically localized pancreatic ductal adenocarcinoma treated with CRT between June 2015 and November 2018. QOL was assessed pre-CRT (immediately before CRT, after neoadjuvant chemotherapy) and at the completion of CRT with the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and its component parts: FACT-General (FACT-G) and hepatobiliary cancer subscore (HCS). A minimally important difference from pre-CRT was defined as ≥ 6, 5, and 8 points for FACT-G, HCS, and FACT-Hep, respectively.ResultsOf 157 patients who underwent CRT, 100 completed both pre- and post-CRT surveys and were included in the primary analysis. Median age at diagnosis was 65 years (range, 23-90). National Comprehensive Cancer Network resectability status was resectable (3%), borderline resectable (40%), or locally advanced (57%). Folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) (75%) or gemcitabine and nab-paclitaxel (42%) were given for a median of 6 cycles (range, 0-42) before CRT. Radiation therapy techniques included 3-dimensional conformal (22%), intensity modulated photon (55%), and intensity modulated proton (23%) radiation therapy to a median dose of 50 Gy (range, 36-62.5). Concurrent chemotherapy was most commonly capecitabine (82%). Sixty-three patients (63%) had surgery after CRT. The mean decline in FACT-G, HCS subscale, and FACT-Hep from pre- to post-CRT was 3.5 (standard deviation [SD], 13.7), 1.7 (SD 7.8), and 5.2 (SD 19.4), respectively. Each of these changes were statistically significant, but did not meet the minimally important difference threshold. Pancreatic head tumor location was associated with decline in FACT-Hep. Nausea was the toxicity with the greatest increase from pre- to post-CRT by both physician-assessment and patient-reported QOL.ConclusionsFor patients with intact pancreatic adenocarcinoma, modern CRT is well tolerated with minimal decline in QOL during treatment. 相似文献
42.
43.
David M. Presby Michael C. Rudolph Vanessa D. Sherk Matthew R. Jackman Rebecca M. Foright Kenneth L. Jones Julie A. Houck Ginger C. Johnson Janine A. Higgins P. Darrell Neufer Robert H. Eckel Paul S. MacLean 《Diabetes》2021,70(4):867
Moderate weight loss improves numerous risk factors for cardiometabolic disease; however, long-term weight loss maintenance (WLM) is often thwarted by metabolic adaptations that suppress energy expenditure and facilitate weight regain. Skeletal muscle has a prominent role in energy homeostasis; therefore, we investigated the effect of WLM and weight regain on skeletal muscle in rodents. In skeletal muscle of obesity-prone rats, WLM reduced fat oxidative capacity and downregulated genes involved in fat metabolism. Interestingly, even after weight was regained, genes involved in fat metabolism were also reduced. We then subjected mice with skeletal muscle lipoprotein lipase overexpression (mCK-hLPL), which augments fat metabolism, to WLM and weight regain and found that mCK-hLPL attenuates weight regain by potentiating energy expenditure. Irrespective of genotype, weight regain suppressed dietary fat oxidation and downregulated genes involved in fat metabolism in skeletal muscle. However, mCK-hLPL mice oxidized more fat throughout weight regain and had greater expression of genes involved in fat metabolism and lower expression of genes involved in carbohydrate metabolism during WLM and regain. In summary, these results suggest that skeletal muscle fat oxidation is reduced during WLM and regain, and therapies that improve skeletal muscle fat metabolism may attenuate rapid weight regain. 相似文献
44.
45.
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46.
47.
Objectives:To reassess the long-term camouflage effects of resin infiltration (Icon, DMG, Hamburg, Germany) of white spot lesions (WSL) and sound adjacent enamel (SAE) achieved in a previous trial. The null hypothesis was tested that there were no significantly different CIE-L*a*b*-ΔE-values between WSL and SAE areas of assessment after at least 24 months (T24) compared to those at baseline (T0).Materials and Methods:Of twenty subjects who received previous resin infiltration treatment of nteeth = 111 nonrestored, noncavitated postorthodontic WSL after multibracket treatment during a randomized controlled trial and were contacted 20 months after baseline, eight subjects (trial teeth nteeth = 40; m/f ratio 1/7; age range (mean; SD) 12–17 [15.25; 2.12] years); response rate: 40%) were available for follow-up after at least 24 months (T24). CIE-L*a*b* differences between summarized color and lightness values (ΔEWSL/SAE) of WSL and SAE were assessed using a spectrophotometer and compared to baseline data assessed prior to infiltration (T0), and those after 6 (T6), and 12 (T12) months using paired t tests at a significance level of α = 5%.Results:T24 assessments were performed after a mean 33.86 (SD: 8.64; Min: 24; Max: 45) months following T0. Mean (SD) ΔEWSL/SAE units of available teeth were 8.76 (5.33) at baseline; 5.5 (2.75) at T6; 5.2 (2.41) at T12; and 5.57 (2.6) at T24. Comparisons of T6, T12, and T24 with T0 yielded highly significant differences, whereas T6–T24 and T12–T24 differences were found to be not significant.Conclusions:Assimilation of infiltrated WSL to the color of adjacent enamel by resin infiltration is considered to be suitable for the long-term improvement in the esthetic appearance of postorthodontic WSL. 相似文献
48.
49.
50.
Clinical Epileptology - Schlafbezogene Atemstörungen sind eine Krankheitsentität mit unterschiedlichen Ursachen, die eine hohe Prävalenz hat. Sie ist Grundlage einer Vielzahl von... 相似文献