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   46586篇
  免费   3808篇
  国内免费   1158篇
耳鼻咽喉   277篇
儿科学   1661篇
妇产科学   1093篇
基础医学   3859篇
口腔科学   1204篇
临床医学   5219篇
内科学   8237篇
皮肤病学   588篇
神经病学   1927篇
特种医学   1051篇
外国民族医学   3篇
外科学   3661篇
综合类   6967篇
现状与发展   2篇
预防医学   5628篇
眼科学   490篇
药学   5189篇
  52篇
中国医学   2388篇
肿瘤学   2056篇
  2024年   65篇
  2023年   968篇
  2022年   1510篇
  2021年   2462篇
  2020年   2300篇
  2019年   2116篇
  2018年   2088篇
  2017年   1761篇
  2016年   1695篇
  2015年   1594篇
  2014年   3227篇
  2013年   3274篇
  2012年   2651篇
  2011年   2994篇
  2010年   2363篇
  2009年   2141篇
  2008年   2039篇
  2007年   2118篇
  2006年   1719篇
  2005年   1524篇
  2004年   1267篇
  2003年   1105篇
  2002年   844篇
  2001年   726篇
  2000年   556篇
  1999年   471篇
  1998年   406篇
  1997年   392篇
  1996年   342篇
  1995年   374篇
  1994年   372篇
  1993年   326篇
  1992年   330篇
  1991年   286篇
  1990年   247篇
  1989年   236篇
  1988年   183篇
  1987年   210篇
  1986年   146篇
  1985年   400篇
  1984年   316篇
  1983年   273篇
  1982年   235篇
  1981年   208篇
  1980年   161篇
  1979年   104篇
  1978年   103篇
  1977年   79篇
  1976年   62篇
  1975年   45篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
目的 探讨丹青胶囊联合他扎罗汀倍他米松治疗银屑病的临床疗效.方法 选取2019年6月—2021年6月在天津市职业病防治院门诊皮肤科就诊治疗的114例银屑病患者,根据随机数字法分为对照组和治疗组,每组各57例.对照组患者给予他扎罗汀倍他米松乳膏,洗净患处,待皮肤干爽后,将适量本品均匀涂抹于患处,1次/d.治疗组患者在对照组治疗基础上口服丹青胶囊,4粒/次,3次/d.两组患者均连续治疗7 d.观察两组患者的临床疗效和临床症状好转时间,比较两组治疗前与治疗1、4、8周的皮损面积和严重程度指数(PASI)评分和血清炎性因子水平.结果 治疗后,治疗组总有效率是98.25%,显著高于对照组的82.46%(P<0.05).治疗后,治疗组患者皮损暗红、皮损肥厚、皮肤瘙痒、皮肤疼痛等症状好转时间均显著短于对照组(P<0.05).治疗后,两组PASI评分均较治疗前显著降低(P<0.05);治疗1、4、8周治疗组PASI评分显著低于对照组(P<0.05).治疗后,两组患者血清炎性因子白细胞介素6(IL-6)、白细胞介素17(IL-17)、肿瘤坏死因子α(TNF-α)、干扰素-γ(IFN-γ)水平均较治疗前显著降低(P<0.05);治疗后,治疗组血清炎性因子水平显著低于对照组(P<0.05).结论 丹青胶囊联合他扎罗汀倍他米松治疗银屑病效果明显,能显著降低炎性因子水平,并有助于改善皮损情况,值得临床推广应用.  相似文献   
32.
ObjectiveTo investigate the association between type 1 diabetes mellitus (T1D) and type 2 diabetes mellitus (T2D) with risk of sudden cardiac arrest (SCA).MethodsIn a prospective community-based study of SCA from February 1, 2002, through November 30, 2019, we ascertained 2771 cases age 18 years of age or older and matched them to 8313 controls based on geography, age, sex, and race/ethnicity. We used logistic regression to evaluate the independent association between diabetes, T1D, T2D, and SCA.ResultsPatients had a mean age of 64.5±15.9 years, were 33.3% female and 23.9% non-White race. Overall, 36.7% (n=1016) of cases and 23.8% (n=1981) of controls had diabetes. Among individuals with diabetes, the proportion of T1D was 6.5% (n=66) among cases and 2.0% among controls (n=40). Diabetes was associated with 1.5-times higher odds of SCA. Compared with those without diabetes, the odds ratio and 95% CI for SCA was 4.36 (95% CI, 2.81 to 6.75; P<.001) in T1D and 1.45 (95% CI, 1.30 to 1.63; P<.001) in T2D after multivariable adjustment. Among those with diabetes, the odds of having SCA were 2.41 times higher in T1D than in T2D (95% CI, 1.53 to 3.80; P<.001). Cases of SCA with T1D were more likely to have an unwitnessed arrest, less likely to receive resuscitation, and less likely to survive compared with those with T2D.ConclusionType 1 diabetes was more strongly associated with SCA compared with T2D and had less favorable outcomes following resuscitation. Diabetes type could influence the approach to risk stratification and prevention of SCA.  相似文献   
33.
《Vaccine》2022,40(24):3320-3329
BackgroundCurrently, booster dose is needed after 2 doses of non-live COVID-19 vaccine. With limited resources and shortage of COVID-19 vaccines, intradermal(ID) administration might be a potential dose-sparing strategy.ObjectiveTo determine immunologic response and reactogenicity of ID ChAdOx1 nCoV-19 vaccine (AZD1222,Oxford/AstraZeneca) as a booster dose after completion of 2-dose CoronaVac(SV) in healthy adult.MethodsThis is a prospective cohort study of adult aged 18–59 years who received 2-dose SV at 14–35 days apart for more than 2 months. Participants received ID AZD1222 at fractional low dose(1×1010 viral particles,0.1 ml). Antibody responses were evaluated by surrogate virus neutralization test(sVNT) against delta variant and wild type, and anti-spike-receptor-binding-domain immunoglobulin G(anti-S-RBD IgG) at prior, day14, 28, 90, and 180 post booster. Solicited reactogenicity was collected for 7 days post-booster. Primary endpoint was the differences of sVNT against delta strain ≥ 80% inhibition at day14 and 90 compared with the parallel cohort study of 0.5-ml intramuscular(IM) route.ResultsFrom August2021, 100 adults with median age of 46 years(IQR 41–52) participated. Prior to booster, geometric mean(GM) of sVNT against delta strain was 22.4% inhibition(95 %CI 18.7–26.9) and of anti-S-RBD IgG was 109.3 BAU/ml(95.4–125.1). Post ID booster, GMs of sVNT against delta strain were 95.5% inhibition (95%CI 94.2–96.8) at day14, 73.1% inhibition (66.7–80.2) at day90, and 22.7% inhibition (14.9–34.6) at day180. The differences of proportion of participants achieving sVNT against delta strain ≥ 80% inhibition in ID recipients versus IM were + 4.2% (95 %CI -2.0to10.5) at day14, and ?37.3%(-54.2to-20.3) at day90. Anti-S-RBD IgG GMs were 2037.1 BAU/ml (95%CI 1770.9–2343.2) at day14 and 744.6 BAU/ml(650.1–852.9) at day90, respectively. Geometric mean ratios(GMRs) of anti-S-RBD IgG were 0.99(0.83–1.20) at day14, and 0.82(0.66–1.02) at day90. Only 18% reported feverish, compared with 37% of IM (p = 0.003). Common reactogenicity was erythema at injection site(53%) while 7% reported blister.ConclusionLow-dose ID AZD1222 booster enhanced lower neutralizing antibodies at 3 months compared with IM route. Less systemic reactogenicity occurred, but higher local reactogenicity.  相似文献   
34.
Objectives: To examine the factors associated with increase in lumbar spine bone mineral density (LS-BMD) by bisphosphonates (BPs) with active vitamin D analog (aVD).

Methods: Two independent postmenopausal osteoporotic patients treated by BPs with aVD for 24 months (Study 1: n?=?93, Study 2: n?=?99) were retrospectively analyzed.

Results: In Study 1, LS-BMD of the patients significantly increased for 24 m (5.4%, p?r2: 0.088, p?=?.02). While average sCa of the patients was 9.2?mg/dL before treatment, it increased time-dependently to 9.6?mg/dL for 24 m by treatment. As each patient had their LS-BMD five times during the study, there were four instances of %LS-BMD in each patient, resulting in 372 instances of %LS-BMD in Study 1. The smallest Akaike’s information criterion value for the most appropriate cut-off levels of sCa for %LS-BMD by treatment every 6 m was 9.3?mg/dL. The %LS-BMD by treatment for 6 m during 24 m period in patients with sCa ≥9.3?mg/dL (1.5%) was significantly higher than that in patients with sCa <9.3?mg/dL (0.8%, p?=?.038). The results of Study 2 were similar to those of Study 1, confirming the phenomena observed.

Conclusion: sCa was associated with an increased LS-BMD by BPs with aVD.  相似文献   
35.
36.
37.
IntroductionThere is a growing interest in physical activity in relation to recovery after surgery. One important aspect of measuring recovery after surgical procedures is postoperative complications. The aim of this study was to determine if there is an association between the preoperative level of habitual physical activity and postoperative complications in patients undergoing elective surgery for colorectal cancer.Materials and methods115 patients scheduled for elective surgery due to colorectal cancer between February 2014 and September 2015 answered a questionnaire regarding physical activity and other baseline variables. Physical activity was assessed using the Saltin-Grimby physical activity level scale. Complications within 30 days after surgery were classified according to Clavien-Dindo, and the Comprehensive Complications Index (CCI) was calculated. Primary outcome was difference in CCI and key secondary outcome was risk for CCI ≥20.ResultsPhysically inactive individuals had a CCI that was 12 points higher than individuals with light activity (p = 0.002) and 17 points higher than regularly active individuals (p = 0.0004). Inactive individuals had a relative risk for a CCI ≥20 that was 65% higher than for individuals reporting light activity (95% confidence interval (CI) for relative risk (RR) = 1.1–2.5) and 338% higher than for regularly active individuals (95% CI for RR = 2.1–9.4).ConclusionSelf-assessed level of habitual physical activity before colorectal cancer surgery was associated with fewer postoperative complications measured with CCI, in a dose-response relationship.  相似文献   
38.
39.
PurposeTo evaluate the safety and efficacy of balloon pulmonary angioplasty (BPA) for nonoperable chronic thromboembolic pulmonary hypertension (CTEPH) patients during the initial experience of a single center.MethodsA total of 18 CTEPH patients (5 with residual pulmonary hypertension after pulmonary endarterectomy) were treated with BPA during the period 2014–2018 and were retrospectively reviewed. Mean age was 61 ± 19 years; 55% were female; mean pulmonary artery pressure was 44 ± 12 mmHg; cardiac output was 4.3 ± 1.0 l/min; and pulmonary vascular resistance was 8.4 ± 3.6 WU. Patients were evaluated by New York Heart Association functional class, 6-minute walk distance, N-terminal pro b-type natriuretic peptide, echocardiography, right heart catheterization, and before and after completions of BPA.ResultsA total of 91 procedures were performed, with a median number of 4 BPA sessions per patient (range, 2–8). There were no deaths or major complications requiring extracorporeal support or (non)invasive ventilation. The most common complication was self-limiting hemoptysis (3%). According to Society of Interventional Radiology classification, 4 mild, 4 moderate, and 1 severe adverse events were noted. Invasive hemodynamics significantly improved, with a cardiac index increase of 15% (P = .0333), decrease of mean pulmonary artery pressure of 30% (P = .0013), and decrease of pulmonary vascular resistance of 45% (P = .0048). Stroke volume index (P = .0171) and pulmonary arterial compliance (P = .0004) were also significantly enhanced.ConclusionsBPA significantly improves cardiopulmonary hemodynamics with an acceptable safety profile. Further studies assessing the long-term efficacy of BPA are required.  相似文献   
40.

Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  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