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   16649篇
  免费   1116篇
  国内免费   568篇
耳鼻咽喉   288篇
儿科学   83篇
妇产科学   331篇
基础医学   368篇
口腔科学   154篇
临床医学   1425篇
内科学   2710篇
皮肤病学   105篇
神经病学   251篇
特种医学   259篇
外国民族医学   4篇
外科学   6033篇
综合类   2448篇
预防医学   465篇
眼科学   136篇
药学   864篇
  23篇
中国医学   135篇
肿瘤学   2251篇
  2024年   13篇
  2023年   357篇
  2022年   551篇
  2021年   801篇
  2020年   780篇
  2019年   634篇
  2018年   637篇
  2017年   655篇
  2016年   729篇
  2015年   676篇
  2014年   1435篇
  2013年   1130篇
  2012年   1108篇
  2011年   1198篇
  2010年   877篇
  2009年   877篇
  2008年   853篇
  2007年   775篇
  2006年   681篇
  2005年   589篇
  2004年   459篇
  2003年   361篇
  2002年   286篇
  2001年   242篇
  2000年   200篇
  1999年   190篇
  1998年   145篇
  1997年   133篇
  1996年   119篇
  1995年   124篇
  1994年   124篇
  1993年   75篇
  1992年   57篇
  1991年   62篇
  1990年   42篇
  1989年   43篇
  1988年   42篇
  1987年   29篇
  1986年   44篇
  1985年   28篇
  1984年   41篇
  1983年   14篇
  1982年   26篇
  1981年   20篇
  1980年   20篇
  1979年   13篇
  1978年   12篇
  1977年   10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 38 毫秒
11.
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   
12.
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   
13.
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   
14.
15.
BackgroundDistal pancreatectomy with celiac axis resection (DP-CAR) is a procedure to secure a surgical margin for a locally advanced pancreatic body cancer that invades the celiac axis. However, in patients with cancer close to the root of the celiac axis, obtaining adequate surgical margins can be difficult because the tumor obstructs the field of vision to the root of the celiac axis. Previously, we described the retroperitoneal-first laparoscopic approach (Retlap) to achieve both accurate evaluation of resectability for locally advanced pancreatic cancer requiring DP-CAR [1] and adequate surgical margin for laparoscopic distal pancreatectomy [2]. In this video, we introduce Retlap-assisted DP-CAR as a minimally invasive approach for performing an artery-first pancreatectomy [3, 4] and achieving sufficient dorsal surgical margin (Fig. 1).MethodsOur patient is a 67-year-old man with a 55 × 29-mm pancreatic body tumor after chemotherapy. Preoperative computed tomography revealed a tumor close to the root of the celiac axis. Because the area of tumor invasion on preoperative images was near the root of the celiac artery, Retlap-assisted DP-CAR was performed to determine whether the celiac axis can be secured and obtain an adequate dorsal surgical margin (Fig. 2).ResultsThe operative time and estimated blood loss was 715 min and 449 mL, respectively. In spite of the advanced tumor's location and size, R0 resection was achieved in a minimally invasive way.ConclusionRetlap-assisted DP-CAR is not only technically feasible and useful for achieving accurate evaluation of resectability but also facilitates obtaining an adequate surgical margin.  相似文献   
16.
肝内胆管癌(ICC)作为第二常见的肝脏恶性肿瘤,虽然R0根治性切除是首选的可治愈方法,但ICC诊断时仅12%~40%病人可获得手术根治的机会,手术后5年存活率也仅为25%~40%。通过辅助化疗和区域治疗降期后可使部分晚期ICC病人获得行根治性手术或肝移植的机会。靶向药物和免疫治疗作为有益的补充,对于有基因突变作用靶点的选择性病人可能会延长生存期。以肝胆外科为主,包含影像科、病理科、肿瘤化疗科、放疗科和介入科的多学科诊疗团队,通过多学科讨论模式,结合病人具体病情,采取个体化、综合化的治疗手段,才能使ICC病人获得最优化的治疗选择。  相似文献   
17.
肝内胆管癌(ICC)是发病率仅次于肝细胞癌的原发性肝癌,其恶性程度高,预后差。近年来,ICC的发病率逐步上升。根治性手术切除是目前可能使病人获得长期生存最有效的治疗方式,但根治性切除率低、术后复发率高仍是外科医生和ICC病人共同面临的巨大阻碍。然而由于ICC发病隐匿和恶性程度高的特性使很多病人初诊时便丧失了手术治疗的机会。因此,早期筛查、准确临床诊断、充分术前评估及完备精准的手术方案是手术赖以顺利实施的保障。癌胚抗原(CEA)和CA19-9对ICC的诊断具有一定价值。影像学检查是诊断ICC的最重要手段。腹部超声是临床第一线的早期筛查手段;CT和MRI是临床上用于ICC最常用的影像学检查。三维重建技术为术前残肝体积预估,手术方案制定提供更直接更精准的信息。建立能准确预测ICC预后的分期系统非常重要。术前减黄是否需要尚存争议。残肝体积和肿瘤是否转移是判断手术可切除性的两个要点。腹腔镜探查、腹腔镜超声检查及术中快速冷冻活检是判断是否可实施根治性切除的重要手段。  相似文献   
18.
19.
20.
目的观察循经艾灸预防乳腺癌患者根治术后上肢水肿的效果。方法采用便利抽样法选取乳腺外科乳腺癌根治术的患者150例,随机分为对照组和观察组,每组75例。对照组行常规护理,观察组在对照组基础上在手术侧上肢循经艾灸。于术前1 d、术后第14天和术后1个月,测量两组患者患侧上肢水肿程度。结果观察组术后患侧上肢水肿发生率低于对照组(P<0.05)。结论术后循经艾灸可有效预防乳腺癌根治术后患侧上肢水肿,提高患者舒适度。  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