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   386392篇
  免费   25254篇
  国内免费   2828篇
耳鼻咽喉   5303篇
儿科学   8348篇
妇产科学   10183篇
基础医学   54269篇
口腔科学   12024篇
临床医学   30620篇
内科学   80019篇
皮肤病学   8634篇
神经病学   27715篇
特种医学   14654篇
外国民族医学   82篇
外科学   61781篇
综合类   9997篇
现状与发展   1篇
一般理论   64篇
预防医学   17592篇
眼科学   9543篇
药学   31612篇
  1篇
中国医学   2208篇
肿瘤学   29824篇
  2021年   2744篇
  2019年   2829篇
  2018年   4664篇
  2017年   3534篇
  2016年   3656篇
  2015年   4167篇
  2014年   5862篇
  2013年   7611篇
  2012年   10347篇
  2011年   10626篇
  2010年   6427篇
  2009年   6069篇
  2008年   9825篇
  2007年   10687篇
  2006年   10618篇
  2005年   9716篇
  2004年   9214篇
  2003年   8959篇
  2002年   8595篇
  2001年   28493篇
  2000年   29010篇
  1999年   23908篇
  1998年   5281篇
  1997年   4340篇
  1996年   3925篇
  1995年   3544篇
  1994年   3165篇
  1993年   2893篇
  1992年   16194篇
  1991年   14959篇
  1990年   14319篇
  1989年   14151篇
  1988年   12732篇
  1987年   12219篇
  1986年   11244篇
  1985年   10461篇
  1984年   7000篇
  1983年   5661篇
  1982年   2751篇
  1979年   5516篇
  1978年   3389篇
  1977年   3018篇
  1975年   2662篇
  1974年   3106篇
  1973年   2889篇
  1972年   2856篇
  1971年   2796篇
  1970年   2536篇
  1969年   2567篇
  1968年   2279篇
排序方式: 共有10000条查询结果,搜索用时 390 毫秒
21.
Objective: Report efficacy findings from three clinical trials (one phase 2 and two phase 3 [OPUS-1, OPUS-2]) of lifitegrast ophthalmic solution 5.0% for treatment of dry eye disease (DED).

Research design and methods: Three 84-day, randomized, double-masked, placebo-controlled trials. Adults (≥18 years) with DED were randomized (1:1) to lifitegrast 5.0% or matching placebo. Changes from baseline to day 84 in signs and symptoms of DED were analyzed.

Main outcome measures: Phase 2, pre-specified endpoint: inferior corneal staining score (ICSS; 0–4); OPUS-1, coprimary endpoints: ICSS and visual-related function subscale (0–4 scale); OPUS-2, coprimary endpoints: ICSS and eye dryness score (EDS, VAS; 0–100).

Results: Fifty-eight participants were randomized to lifitegrast 5.0% and 58 to placebo in the phase 2 trial; 293 to lifitegrast and 295 to placebo in OPUS-1; 358 to lifitegrast and 360 to placebo in OPUS-2. In participants with mild-to-moderate baseline DED symptomatology, lifitegrast improved ICSS versus placebo in the phase 2 study (treatment effect, 0.35; 95% CI, 0.05–0.65; p?=?0.0209) and OPUS-1 (effect, 0.24; 95% CI, 0.10–0.38; p?=?0.0007). Among more symptomatic participants (baseline EDS ≥40, recent artificial tear use), lifitegrast improved EDS versus placebo in a post hoc analysis of OPUS-1 (effect, 13.34; 95% CI, 2.35–24.33; nominal p?=?0.0178) and in OPUS-2 (effect, 12.61; 95% CI, 8.51–16.70; p?<?0.0001).

Limitations: Trials were conducted over 12 weeks; efficacy beyond this period was not assessed.

Conclusions: Across three trials, lifitegrast improved ICSS in participants with mild-to-moderate baseline symptomatology in two studies, and EDS in participants with moderate-to-severe baseline symptomatology in two studies. Based on the overall findings from these trials, lifitegrast shows promise as a new treatment option for signs and symptoms of DED.  相似文献   
22.
23.
24.
25.
26.
27.
28.
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   
29.
30.
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   
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