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   124067篇
  免费   9678篇
  国内免费   5244篇
耳鼻咽喉   639篇
儿科学   2192篇
妇产科学   906篇
基础医学   11369篇
口腔科学   3530篇
临床医学   16558篇
内科学   13040篇
皮肤病学   981篇
神经病学   8591篇
特种医学   8007篇
外国民族医学   10篇
外科学   20723篇
综合类   21161篇
一般理论   1篇
预防医学   5722篇
眼科学   1401篇
药学   9971篇
  56篇
中国医学   4850篇
肿瘤学   9281篇
  2024年   115篇
  2023年   1923篇
  2022年   2865篇
  2021年   4575篇
  2020年   4753篇
  2019年   3854篇
  2018年   3792篇
  2017年   4395篇
  2016年   4274篇
  2015年   4298篇
  2014年   8233篇
  2013年   9368篇
  2012年   7565篇
  2011年   8630篇
  2010年   6832篇
  2009年   6814篇
  2008年   6832篇
  2007年   6802篇
  2006年   6202篇
  2005年   5471篇
  2004年   4503篇
  2003年   4003篇
  2002年   3187篇
  2001年   2873篇
  2000年   2380篇
  1999年   1986篇
  1998年   1581篇
  1997年   1418篇
  1996年   1182篇
  1995年   1168篇
  1994年   942篇
  1993年   708篇
  1992年   678篇
  1991年   556篇
  1990年   487篇
  1989年   435篇
  1988年   380篇
  1987年   339篇
  1986年   277篇
  1985年   379篇
  1984年   291篇
  1983年   198篇
  1982年   238篇
  1981年   247篇
  1980年   233篇
  1979年   143篇
  1978年   126篇
  1977年   99篇
  1976年   110篇
  1975年   56篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
IntroductionLung cancer (LC) is usually diagnosed at advanced stages with only a 12% 5-year survival. Trials as NLST and NELSON show a mortality decrease, which justifies implementation of lung cancer screening in risk population. Our objective was to show survival results of the largest LC screening program in Spain with low dosage computed tomography (LDCT).MethodsClinical records from International Early Lung Cancer Detection Program (IELCAP) at Valencia, Spain were analysed. This program recruited volunteers, ever-smokers aged 40-80 years, since 2008. Results are compared to those from other similar sizeable programs.ResultsA total of 8278 participants were screened with at least two-rounds until November 2020. A mean of 6 annual screening rounds were performed. We detected 239 tumours along 12-year follow-up. Adenocarcinoma was the most common histology, being 61.3% at stage I. The lung cancer prevalence and incidence proportion was 1.5% and 1.4%, respectively with an annual detection rate of 0.17. One-year survival and 10-year survival were 90% and 80.1%, respectively. Adherence was 96.84%.ConclusionLargest lung cancer screening in Spain shows that survival is improved when is performed in multidisciplinary team experienced in management of LC, and is comparable to similar screening programs.  相似文献   
2.
3.
4.
目的探讨肺癌患者化疗后的癌胚抗原(CEA)、神经元特异性烯醇化酶(NSE)和鳞状上皮细胞癌抗原(SCC-Ag)表达变化。方法选取2017年5月至2020年2月间南京市六合区人民医院收治的100例肺癌患者,将这些患者作为肺癌组,另随机选取同期100例健康体检人员作为健康组。统计分析两组人员化疗前的血清NSE、CEA、SCC-Ag表达水平、肺癌组化疗成功患者化疗前后的血清NSE、CEA、SCC-Ag表达水平、肺癌组化疗失败患者化疗前后的血清NSE、CEA、SCC-Ag表达水平。结果肺癌组患者化疗前的血清NSE、CEA和SCC-Ag表达水平均高于健康组,差异均有统计学意义(均P <0.05)。肺癌组化疗成功患者化疗后的血清NSE、CEA和SCC-Ag表达水平均低于化疗前,均高于健康组,差异均有统计学意义(P <0.05)。肺癌组化疗失败患者化疗后的血清NSE、CEA、SCC-Ag表达水平均高于化疗前,均高于健康组,差异均有统计学意义(P <0.05)。结论对肺癌患者的NSE、CEA、SCC-Ag表达水平进行检测能够将化疗效果有效反映出来,进而有效指导临床的下一步治疗工作,从而有效改善患者预后。  相似文献   
5.
Background: Thyrosin kinase inhibitors (TKIs) is approved for the first line treatment of non-small cell lung cancer (NSCLC) patients with  epidermal growth factor receptor (EGFR) mutation. This study performed to assess clinical effectiveness and safety of Erlova (generic form of Erlotinib). Methods: Somatic mutations of EGFR gene were studied in tumor tissue by polymerase chain reaction (PCR) and bi-directional sequencing in 513 chemonaive and histologically verified lung adenocarcinoma Iranian patients. Patients  with EGFR mutation received Erlova at 150 mg/day  as first line treatment. Primary endpoint was progression free survival (PFS). Results: About 21% (n=109) cases had EGFR mutation. Most EGFR mutations were  occurred at exon 19. Among them, sixty nine patients treated with Erlova. Median PFS was 11.4 months and objective response rate (ORR) was about  88%. Most frequent treatment related adverse events was  skin rash. Conclusion: Our findings showed Erlova had remarkable effectiveness. In  mutation-positive patients with EGFR, Erlova can be used  safely instead of  other tyrosine-kinase inhibitors.  相似文献   
6.
7.
ObjectiveTo analyze the effects of electrolysis, through a medium frequency current, associated to aerobic physical activity in the body composition of young women.MethodsThe study was composed of 34 sedentary women (24.35 ± 4.43 years, 71.30 ± 7.08 kg, 1.61 ± 0.06 m, 27.31 ± 1.67 kg/m2) which were evaluated for their anthropometric measures and body composition. The volunteers were randomly assigned to two group: Electrolyphysis plus Aerobic Exercise (gEEA): 17 volunteers were submitted to the application, for 60 min , of the Aussie current, followed by aerobic physical activity (77% of HRmax) on the trampoline for 40 min, through video-lessons of Jump; and Aerobic Exercise group (gEA): 17 volunteers performed only physical activity following the same parameters mentioned above. Each group performed its protocols twice weekly, for 5 weeks, totaling 10 sessions. For the data analysis, measures repeated ANOVA was performed to compare the means of the variables analyzed before and after the treatment protocols using the SPSS - 21.0 software, adopting a p ≤ 0.05.ResultsAlthough gEEA decreased suprailiac skinfold (p = 0.04), abdominal skinfold (p = 0.03) and circumference at umbilical scar (p = 0.02) in an intragroup analysis, these means differences in anthropometric measures were not important between-groups (p > 0.05). Furthermore, there were no effect of treatment on body composition (p > 0.05).ConclusionTo this studied condition, our results suggested that application of medium frequency electrolysis did not enhance the losses on anthropometric measures and body composition.  相似文献   
8.
目的 观察治伤巴布剂对急性软组织损伤(acute soft tissue injury, ASTI)模型p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)、丝/苏氨酸蛋白激酶(AKT)信号通路的影响,探讨治伤巴布剂干预ASTI的可能作用机制。方法 将40只雄性SD大鼠按照随机数字表法分为正常对照组、模型对照组、治伤巴布剂组、p38MAPK信号通路抑制剂组、AKT信号通路抑制剂组,每组8只。除正常对照组外,其余四组均予以左侧后肢小腿ASTI造模。造模成功后,治伤巴布剂组于标记部位立即予治伤巴布剂(修剪成1.5x3cm大小)外敷,并用胶布固定;其余四组均予等剂量赋形剂(修剪成1.5×3 cm大小)外敷处理,胶布固定;持续外敷,共持续24 h。p38MAPK信号通路抑制剂组在造模前30 min予腹腔注射p38MAPK信号通路抑制剂SB203580(400 μg/kg/天)1次;AKT信号通路抑制剂组在造模前30 min予腹腔注射AKT信号通路抑制剂perifosine(20 mg/kg/天)1次。分别于0(造模前)、2h、4h、8h、12h、24h测量受伤小腿肌肉处的周长,并计算肌肉肿胀率(muscle swelling rate,MSR)。24 h药物干预结束后,采用颈椎脱臼法处死大鼠。后将左侧后肢小腿损伤中心部位进行取材,分成三份。一部分用于观察组织病理学形态变化;一部分用于逆转录聚合酶链反应(RT-PCR)检测核因子-κB(nuclear factor kappa-B,NF-κB)p65 mRNA、肿瘤坏死因子-α(TNF-α)mRNA、白细胞介素-1β(IL-1β)mRNA表达水平;剩下部分用酶联免疫吸附试验(ELISA)法检测骨骼肌组织TNF-α、IL-1β含量水平及蛋白质免疫印迹(Western-blot)法测定p38MAPK、AKT、NF-κB p65、核因子抑制蛋白α(inhibitor kappa B alpha, IκBα)表达水平。结果 与正常对照组相比,模型对照组MSR显著增加(P<0.01);病理形态学上,骨骼肌组织可见大面积肌细胞排列紊乱,肌细胞变性坏死,间质内可见红细胞聚集及大量炎症细胞浸润;骨骼肌组织TNF-α、IL-1β含量水平显著升高(P<0.01);磷酸化p38MAPK(p-p38)/总p38MAPK(t-p38),磷酸化-AKT(p-AKT)/总-AKT(t-AKT)明显升高(P<0.01),NF-κB p65及NF-κB p65mRNA表达水平明显升高(P<0.01)。与模型对照组相比,治伤巴布剂组MSR在治疗第8 h、12 h、24 h显著下降(P<0.01),且在治疗第24 h,其MSR较p38MAPK、AKT信号通路抑制剂组下降更明显(P<0.05);病理学评分显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组下降更显著(P<0.05);骨骼肌组织TNF-α、IL-1β含量水平明显下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组更显著(P<0.05);p-p38/t-p38及p-AKT/t-AKT明显下降(P<0.01),NF-κB p65及NF-κB p65 mRNA表达水平显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组在降低NF-κB p65及NF-κB p65 mRNA相对表达值方面更显著(P<0.01)。结论 治伤巴布剂可能同时对p38MAPK、AKT信号通路产生了一定的抑制作用,引起NF-κB活性下调,NF-κB p65蛋白的表达下调,进而引起骨骼肌组织TNF-α、IL-1β炎性细胞因子含量水平下调,减轻ASTI炎症反应,从而改善ASTI。  相似文献   
9.
BackgroundIntraabdominal and retroperitoneal sarcomas (IaRS) are malignant connective tissue tumors. Surgical resection is often the only curative treatment. The primary objective was to report the mid-term outcomes following contemporary treatment protocols and identify prognostic factors.MethodsA retrospective review of consecutive patients (n = 107) with IaRS treated at single center from 2013 until 2018 was conducted. Histological diagnosis, tumor grade, perioperative complications, mortality, and long-time survival were registered and retrieved from patient records. Primary and recurrent tumors were analyzed separately.ResultsA total of 107 patients were identified. Median follow-up time was 3.5 years. Thirty-day mortality was 3.4% and 90-day mortality was 5.6% for all tumors. The major complication rate was 18%. The 5-year estimated survival for primary and recurrent tumors was 55.4% and 48.4%, respectively. Multifocal disease was evident in 32% of the patient cohort, and 58% of patients in the recurrent group. Multivariate analysis for survival revealed a hazard ratio (HR) of 3.1 (95% CI 1.68–8.41) for multifocality, HR 2.9 (95% CI 1.28–6.98) for Clavien-Dindo grade, HR 2.3 (95% CI 1.21–4.31) for tumor grades 2 or 3, and HR 1.002 (95% CI 1.001–1.004) for surgical margins.ConclusionsOur study found overall acceptable morbidity and mortality, and identified prognostic markers for overall survival. Recurrent tumors were not associated with worse survival. Multifocality is associated with a worse overall survival. The prognostic factors identified were; tumor grade, multifocality, intralesional margins and postoperative complications.  相似文献   
10.
In the pelvis, anatomic complexity and difficulty in visualization and access make surgery a formidable task. Surgeons are prone to work-related musculoskeletal injuries from the frequently poor design and flow of their work environment. This is exacerbated by the strain of surgery in the pelvis. These injuries can result in alterations to a surgeons practice, inadvertent patient injury, and even early retirement. Human factors examines the relationships between the surgeon, their instruments and their environment. By bridging physiology, psychology, and ergonomics, human factors allows a better understanding of some of the challenges posed by pelvic surgery. The operative approach involved (open, laparoscopic, robotic, or perineal) plays an important role in the relevant human factors. Improved understanding of ergonomics can mitigate these risks to surgeons. Other human factors approaches such as standardization, use of checklists, and employing resiliency efforts can all improve patient safety in the operating theatre.  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