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   53684篇
  免费   3301篇
  国内免费   735篇
耳鼻咽喉   364篇
儿科学   917篇
妇产科学   557篇
基础医学   2427篇
口腔科学   832篇
临床医学   6157篇
内科学   5035篇
皮肤病学   673篇
神经病学   2605篇
特种医学   919篇
外科学   3478篇
综合类   12107篇
一般理论   2篇
预防医学   4979篇
眼科学   304篇
药学   9076篇
  160篇
中国医学   4915篇
肿瘤学   2213篇
  2024年   138篇
  2023年   863篇
  2022年   1814篇
  2021年   2374篇
  2020年   2277篇
  2019年   1903篇
  2018年   1763篇
  2017年   1974篇
  2016年   2293篇
  2015年   2249篇
  2014年   6088篇
  2013年   5305篇
  2012年   4947篇
  2011年   4646篇
  2010年   3395篇
  2009年   2395篇
  2008年   2154篇
  2007年   1943篇
  2006年   1555篇
  2005年   1124篇
  2004年   872篇
  2003年   712篇
  2002年   554篇
  2001年   475篇
  2000年   435篇
  1999年   323篇
  1998年   254篇
  1997年   210篇
  1996年   169篇
  1995年   149篇
  1994年   144篇
  1993年   107篇
  1992年   72篇
  1991年   73篇
  1990年   65篇
  1989年   73篇
  1988年   54篇
  1987年   61篇
  1986年   60篇
  1985年   153篇
  1984年   229篇
  1983年   195篇
  1982年   210篇
  1981年   181篇
  1980年   148篇
  1979年   147篇
  1978年   101篇
  1977年   65篇
  1976年   74篇
  1975年   67篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
目的探讨闭合性脑外伤患者恢复后期的记忆障碍特点。方法用临床记忆量表对 2 0例闭合性脑外伤患者恢复后期及 2 0例正常人进行记忆测验。结果闭合性脑外伤患者恢复后期 5项分测验及记忆商均明显低于正常人对照组 ,MQ≤ 79的比例较正常人明显增高。结论闭合性脑外伤患者恢复后期有非常严重的记忆障碍 ,其回忆比再认受损更严重  相似文献   
102.
Chronic nasal obstruction in children is a very common disorder. Obstructing adenoid is usually the first to blame. Though the clinical assessment is essential, it is often considered unreliable or insufficient. We conducted a prospective clinical study to validate a clinical score predicting the severity of adenoid obstruction in symptomatic children. The clinical score (CS) included mouth breathing, snoring, restless sleep, frequent waking-up at night and obstructive breathing during sleep. Each item received a score of 0 or 1. The palatal airway was evaluated on a lateral nasopharyngeal x-ray. The degree of obstruction was assessed intra-operatively by a laryngeal mirror using a 3-grade scale. The volume of each adenoid specimen was measured. Eighty-six patients were enrolled, 51 boys and 35 girls, aged 13–181 months (mean 52, median 45). The CS correlated very well with the intra-operative findings (p < 0.01) and with the degree of palatal airway obstruction (p < 0.05) but not with the volume of the adenoid removed (p > 0.05). The CS was higher in children younger than 3 years (CS > 3 in 85.7% vs. 29.2%), having more frequent obstructive breathing during sleep (71.43% vs. 21.54%). A CS of three or higher, predicted severe obstruction in 96.5% of patients, as detected intra-operatively. The suggested CS is simple to use and is highly reliable in identifying children in need for adenoidectomy, in the context of normal anterior rhinoscopy and tonsils less than grade three.This work was presented at the podium of the XVIII IFOS in Rome, Italy on June 26, 2005.  相似文献   
103.
目的探讨心力衰竭并发心律失常的发病规律及治疗方法。方法回顾性分析了93例慢性心力衰竭病人的临床资料,包括临床特点、诊断治疗方法以及预后。结果心律失常发生率为60.2%,以室性早搏发生率最高32.1%,其次是房性早搏26.8%,心房纤颤21.4%,其他19.7%,经治疗有效71例,总有效率76.3%。结论纠正心功能不全是治疗的关键,应根据具体情况选择性地应用抗心律失常药。  相似文献   
104.
For patients with community-acquired pneumonia (CAP), clinical response during the first days of treatment is predictive of clinical outcome. As risk assessments can improve the efficiency of pneumonia management, a prospective cohort study to assess clinical, biochemical and microbiological predictors of early clinical failure was conducted in patients with severe CAP (pneumonia severity index score of >90 or according to the American Thoracic Society definition). Failure was assessed at day 3 and was defined as death, a need for mechanical ventilation, respiratory rate >25/min, PaO2 <55 mm Hg, oxygen saturation <90%, haemodynamic instability, temperature >38 degrees C or confusion. Of 260 patients, 80 (31%) had early clinical failure, associated mainly with a respiratory rate >25/minute (n = 34), oxygen saturation <90% (n = 28) and confusion (n = 20). In multivariate logistic regression analysis, failure was associated independently with altered mental state (OR 3.19, 95% CI 1.75-5.80), arterial PaH <7.35 mm Hg (OR 4.29, 95% CI 1.53-12.05) and PaO2 <60 mm Hg (OR 1.75, 95% CI 0.97-3.15). A history of heart failure was associated inversely with clinical failure (OR 0.30, 95% CI 0.10-0.96). Patients who failed to respond had a higher 28-day mortality rate and a longer hospital stay. It was concluded that routine clinical and biochemical information can be used to predict early clinical failure in patients with severe CAP.  相似文献   
105.
Objective To investigate the clinical characteristics and imaging manifestations of AIDS complicated with disseminated Penicillium marneffei (PM) infection. Methods A total of 12 patients with AIDS complicated with disseminated PM infection were collected and the symptoms, signs, laboratory examination results and image manifestations of these patients were analyzed retrospectively. Results (1) The diagnosis of PM infection in all the 12 cases were confirmed by peripheral blood culture. All the 12 cases (100%) had irregular fever (38-41℃) and enlarged lymph nodes, 8 cases (66%) had skin rashes; 8 cases (66%) had hepatomegaly; 9 cases (75%) had splenomegaly while 8 cases (66%) had anemia. (2) Imaging manifestation: Five cases manifested bilateral pulmonary disseminated miliary nodular shadows or lattice signs; 1 case showed enlarged hilar lymph node and 2 cases showed patchy shadow with pleuritis. One case presented sub-pleural curve line shadow at the posterior part of the right lower lung, and adhesion between the intestinal wall and intestinal mesentery in mass form in the abdomen by CT examination. Conclusion Patients suffering from AIDS (CD4 T lymphocytes 〈50/μ L) with impaired immunity might be susceptible to complication of disseminated PM infection, which presents mainly damage of multiple organs and symptoms such as fever; enlargement of liver, spleen and lymph nodes, as well as specific skin maculopapular rashes. Imaging manifestations in the lungs were revealed as miliary nodular shadows and lattice-like shadows. Intensified abdominal CT might reveal presence of several enlarged postperitoneal lymph nodes and intestinal adhesion in shape of "cakes".  相似文献   
106.
慢性多发性肌炎临床及病理分析   总被引:1,自引:0,他引:1  
目的探讨慢性多发性肌炎的发病机制、临床和病理特征。方法回顾性分析95例慢性多发性肌炎患者临床表现、肌酶学和肌电图检查结果,总结肌肉病理学特征。结果慢性多发性肌炎以四肢近端肌无力、肌萎缩为主要表现,血清酶谱轻-中度增高,肌电图以肌源性损害为主,病理改变为灶性坏死、炎性细胞浸润与再生肌纤维共存。结论临床特点结合病理学检查有助于慢性多发性肌炎的诊断,多数患者激素治疗有效。  相似文献   
107.
目的:通过对HIV抗体快速检测试剂的临床评估,为HIV检测试剂的临床应用提供参考.方法:对快速试剂的使用性能进行比较,并采用美国输血协会(AABB)血清盘、临床样品血清盘、特性血清盘(阳性样品盘)、稀释系列血清盘评估快速试剂的敏感性和特异性.结果:三种快速试剂在检测AABB血清盘时,敏感性分别是86.4%、86.4%、100%,特异性皆为100%;三种快速试剂在检测临床样品血清盘时,敏感性分别是88.6%、91.4%、97.1%,特异性皆为100%.快速试剂具有很高的阳性预期值,对于低危人群(感染率很低人群)也具有很高的阴性预期值.快速试剂检测弱阳性的样品(酶联试剂s/co比值小于6~8的样品)存在漏检.快速试剂与ELISA参考试剂在分析灵敏度方面相差3个以上倍比稀释度.结论:快速试剂具有较好的使用特性,非常适用于样本量较少的实验室及对低危人群的HIV筛查,在对高危人群筛查时,可能有弱阳性样品漏检,同时快速试剂在分析灵敏度方面有待提高.  相似文献   
108.
We conducted a noninvasive near-infrared spectroscopy (NIRS) study using the game of rock, paper, scissors (RPS) as a simple neurocognitive task for the prefrontal cortex (PFC) in 15 healthy volunteers. We employed an opposite “to lose” RPS task coupled with a normal “to win” RPS task, since the former requires inhibition of behavior, one of the most important functions of the prefrontal cortex. During the NIRS examination, subjects had to present one of the three RPS hands in response to hands displayed randomly on a computer screen every 1.5 s, and were required to show hands that lose to the computer, or that beat the computer. We measured the relative concentrations of oxyhemoglobin (oxy-Hb) using the prefrontal probes of the NIRS system during the tasks. The increases in oxy-Hb during the “to win” RPS task were small, but were quite large and laterally dominant during the “to lose” RPS task. The difference between the two tasks might have been due to the participants’ cognitive conflict with losing on the RPS. We conclude that losing is better than winning on the RPS as a sensitive indicator in the NIRS examination of PFC.  相似文献   
109.
肘关节后脱位并尺骨冠状突骨折9例临床疗效分析   总被引:6,自引:0,他引:6  
目的 探讨肘关节后脱位并尺骨冠状突骨折的治疗方法。方法 总结2000年3月~2003年5月9例肘关节后脱位合并尺骨冠状突骨折患者的治疗经验,根据骨折类型分别采用内外侧入路对8例患者进行手术治疗,术后配合早期功能锻炼。结果 所有患者随访8~24个月,根据HSS评分标准,优5例(55.6%),良2例(22.2%),一般2例(22.2%),优良率77.8%,无严重肘关节并发症发生。结论 选择恰当的手术入路和早期功能锻炼是提高该类骨折效果的关键。  相似文献   
110.
目的 :探讨单纯疱疹性角膜炎是中西医联合用药的治疗方法。方法 :本组 10 0例 ( 10 6只眼 )单纯疱疹性角膜炎患者应用抗病毒药物联合清热解毒中药的疗效观察。结果 :本组病例治疗后总有效率 82 .0 8%。结论 :中西医联合治疗措施是我们对单纯疱疹性角膜炎治疗的一项新的探讨。  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