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   14117篇
  免费   1023篇
  国内免费   535篇
耳鼻咽喉   212篇
儿科学   72篇
妇产科学   200篇
基础医学   300篇
口腔科学   149篇
临床医学   1311篇
内科学   2615篇
皮肤病学   87篇
神经病学   240篇
特种医学   221篇
外国民族医学   4篇
外科学   5017篇
综合类   2025篇
预防医学   405篇
眼科学   137篇
药学   710篇
  21篇
中国医学   107篇
肿瘤学   1842篇
  2024年   11篇
  2023年   325篇
  2022年   458篇
  2021年   678篇
  2020年   687篇
  2019年   564篇
  2018年   534篇
  2017年   535篇
  2016年   654篇
  2015年   599篇
  2014年   1194篇
  2013年   977篇
  2012年   911篇
  2011年   985篇
  2010年   729篇
  2009年   720篇
  2008年   728篇
  2007年   694篇
  2006年   576篇
  2005年   501篇
  2004年   413篇
  2003年   310篇
  2002年   259篇
  2001年   211篇
  2000年   163篇
  1999年   170篇
  1998年   129篇
  1997年   112篇
  1996年   105篇
  1995年   114篇
  1994年   109篇
  1993年   64篇
  1992年   45篇
  1991年   50篇
  1990年   34篇
  1989年   39篇
  1988年   36篇
  1987年   27篇
  1986年   43篇
  1985年   25篇
  1984年   38篇
  1983年   14篇
  1982年   26篇
  1981年   16篇
  1980年   13篇
  1979年   13篇
  1978年   11篇
  1977年   9篇
  1976年   5篇
  1973年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
ObjectiveTo systematically evaluate the clinicopathological and prognostic value of extra-hepatic bile duct resection (EHBDR) in the surgical management of patients with gallbladder carcinoma (GBC), especially in non-jaundiced patients.MethodsPubMed, EMBASE and the Cochrane Library were searched up to March 1st 2021 for comparative studies between bile duct resected and non-resected groups. RevMan5.3 and Stata 13.0 software were used for the statistical analyses.ResultsEHBDR did not correlate with a better overall survival (OS) (P = 0.17) or disease-free survival (P = 0.27). No survival benefit was also observed in patients with T2N1 (P = 0.4), T3N0 (P = 0.14) disease and node-positive patients (P = 0.75), rather, EHBDR was even harmful for patients with T2N0 (P = 0.01) and node-negative disease (P = 0.02). Significantly higher incidences of recurrent disease (P = 0.0007), postoperative complications (P < 0.00001) and positive margins (P = 0.02) were detected in the bile duct-resected group. The duration of postoperative hospital stay between the two groups was comparable (P = 0.58). Selection bias was also detected in our analysis that a significantly higher proportion of advanced lesions with T3-4 or III-IV disease was observed in the bile duct-resected group (P < 0.00001). EHBDR only contributed to a greater lymph yield (P = 0.01).ConclusionEHBDR has no survival advantage for patients with GBC, especially for those with non-jaundiced disease. Considering the unfairness of comparing OS between jaundiced patients receiving EHBDR with non-jaundiced patients without EHBDR, we could only conclude that routine EHBDR in non-jaundiced patients is not recommended and future well-designed studies with more specific subgroup analyses are required for further validation.  相似文献   
2.
《Digestive and liver disease》2022,54(11):1486-1493
BackgroundCold snare polypectomy (CSP) is a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. However, the efficacy and safety of this technique remain undetermined.AimsWe aimed to comprehensively evaluate the efficacy and safety of CSP for SSPs ≥ 10 mm.MethodsPubMed, EMBASE, Web of Science and Cochrane Library were searched up to January 2021.ResultsA total of 10 studies consisting of 1727 SSPs (range, 10–40 mm) from 1021 patients were included. The overall rates of technical success, adverse events (AEs) and residual SSPs were 100%, 0.7% and 2.9%, respectively. Subgroup analysis showed that the rates of technical success and AEs were comparable between CSP and cold endoscopic mucosal resection (EMR) (99.9% vs. 100% and 1.3% vs. 0.5%, respectively), between the proximal and distal colon (100% vs. 99.9% and 0.3% vs. 0, respectively), and between polyps of 10–19 mm and ≥20 mm (99.8% vs. 100% and 0.9% vs. 0, respectively). However, subgroup analysis showed that the rate of residual SSPs was slightly lower in CSP compared with cold EMR (1.3% vs. 3.9%), as well as in polyps of 10–19 mm compared with those ≥20 mm (3.1% vs. 4.7%).ConclusionCSP was an effective and safe technique for removing SSPs ≥ 10 mm.  相似文献   
3.
PurposeTo review and to compare indirectly the outcomes of minimally invasive therapies for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia.Materials and MethodsA literature search via Medline and Cochrane Central databases was completed for randomized control studies published between January 2000 to April 2020 for the following therapies: Rezum, Urolift, Aquablation, and prostatic artery embolization (PAE). Data on the following variables were included: International prostate symptom score (IPSS), maximum urinary flow rate, quality of life, and postvoid residual (PVR). Standard mean differences between treatments were compared through a meta-analysis using transurethral resection of the prostate (TURP) to assess differences in treatment effect.ResultsThere was no significant difference in outcomes between therapies for IPSS at the 3, 6, and 12-month follow ups. Although outcomes for Rezum were only available out to 3 months, there were no consistently significant differences in outcomes when comparing Aquablation versus PAE versus Rezum. TURP PVR was significantly better than Urolift at 3, 6, and 12 months. No significant differences in minor or major adverse events were noted.ConclusionAlthough significant differences in outcomes were limited, Aquablation and PAE were the most durable at 12 months. PAE has been well studied on multiple randomized control trials with minimal adverse events while Aquablation has limited high quality data and has been associated with bleeding-related complications.  相似文献   
4.
BackgroundLiver resection is commonly performed for hepatic tumors, however preoperative risk stratification remains challenging. We evaluated the performance of contemporary prediction models for short-term mortality after liver resection in patients with and without cirrhosis.MethodsThis retrospective cohort study examined National Surgical Quality Improvement Program data. We included patients who underwent liver resections from 2014 to 2019. VOCAL-Penn, MELD, MELD-Na, ALBI, and Mayo risk scores were evaluated in terms of model discrimination and calibration for 30-day post-operative mortality.ResultsA total 15,198 patients underwent liver resection, of whom 249 (1.6%) experienced 30-day post-operative mortality. The VOCAL-Penn score had the highest discrimination (area under the ROC curve [AUC] 0.74) compared to all other models. The VOCAL-Penn score similarly outperformed other models in patients with (AUC 0.70) and without (AUC 0.74) cirrhosis.ConclusionThe VOCAL-Penn score demonstrated superior predictive performance for 30-day post-operative mortality after liver resection as compared to existing clinical standards.  相似文献   
5.
6.
7.
目的探讨眼睑恶性肿瘤切除术中应用Z形皮瓣及推进皮瓣I期修复眼睑缺损的临床效果。方法将50例眼睑恶性肿瘤切除术患者按不同缝合方法分为两组,即对照组25例,术中直接缝合;观察组25例,术中行Z形皮瓣及推进皮瓣I期修复;比较两组眼睑修复效果。结果观察组术后皮瓣成活率96.0%、切口Ⅰ期愈合率100%、修复满意率92.0%,均高于对照组的72.0%、68.0%、56.0%,差异有统计学意义(P<0.05)。观察组术后并发症发生率低于对照组,但差异无统计学意义(P>0.05)。结论眼睑恶性肿瘤切除术中眼睑缺损修复时,采用Z形皮瓣及推进皮瓣,眼睑修复良好,患者修复满意率高,值得推广应用。  相似文献   
8.
BackgroundThe influence of positive microscopic margin (R1) resection on the prognosis of gastrointestinal stromal tumors (GISTs) is controversial. Tumor rupture is significantly associated with the occurrence of R1 resection and may be a confounder of R1 resection in GISTs. The present meta-analysis evaluated the real influence of R1 resection on the prognosis of GISTs by excluding the confounding effect of tumor rupture.MethodsThe PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov databases were searched. Studies that compared R1 with negative microscopic margin (R0) resection in GIST patients and reported the time-to-event data of recurrence-free survival (RFS) or disease-free survival (DFS) were eligible for inclusion. The quality of the observational studies was assessed using the Newcastle–Ottawa scale.ResultsOf the 4896 records screened, 23 retrospective studies with 6248 participants were selected. In the overall analysis, R1 resection resulted in a significantly shorter RFS/DFS than R0 resection for GISTs (HR = 1.80, 95% CI = 1.54–2.10, P < 0.001, I2 = 14%). However, the inferior RFS/DFS vanished when tumor rupture cases were excluded (HR = 1.34, 95% CI = 0.98–1.83, P = 0.07, I2 = 33%). Sensitivity analysis by high-quality studies brought about a more robust HR of 1.15 (95% CI = 0.88–1.50, P = 0.29), with low heterogeneity (I2 = 0%). The qualities of evidence for the outcomes were high.ConclusionsThis meta-analysis shows that R1 resection did not influence the survival outcome of GISTs. Reresection may not be necessary when positive microscopic margins exist. This analysis could provide high-quality evidence for the development of guidelines.  相似文献   
9.
目的探讨1470 nm激光在解剖性切除非肌层浸润性膀胱癌中的临床疗效。方法回顾性分析2018年1月至2019年12月于本院泌尿外科行1470 nm激光解剖性切除浅表性膀胱肿瘤患者60例的临床资料,所有患者均通过膀胱镜检查和CT或MRI检查,术前诊断为非肌层浸润性膀胱癌。分析1470 nm激光在解剖性切除非肌层浸润性膀胱癌中的应用效果。结果所有患者均顺利完成手术,无中转开放手术,并且术中无并发症,手术时间为10~30 min,平均(15.3±4.9)min,术后冲洗液无色或淡粉色,未见血块,术后1周拔除导尿管。结论1470 nm激光应用于解剖性切除浅表性膀胱肿瘤中效果显著,具有无瘤原则,利于肿瘤分期,可减少闭孔反射。  相似文献   
10.
目的探究可拆卸经鼻垂体腺瘤切除操作模型的真实性,并初步探讨了模型的教学性。方法利用患者CT建模、精细优化及3D打印技术构建可拆卸垂体腺瘤切除模型。评估者为19名来自北京协和医院的本院及进修医师,其中年资<10分入"低年资组";年资≥10分入"高年资组"。每位医师分别对3D打印垂体腺瘤切除模型进行操作,并于操作前后分别填写调查问卷、评估量表。结果高年资组的探查经验均高于低年资组。真实度项目的得分均在4附近,各评分项间无明显差异;"切除垂体腺瘤"步骤的真实性评分相对较低;高年资组评分普遍低于低年资组。操作前低年资组信心评分显著低于高年资组,操作后两组评分趋于一致;低年资组的垂体腺瘤切除信心评分变化显著高于高年资组(P<0.05)。结论该模型具有较高的真实性,可用于教学试验进一步评估教学效果。  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