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71.
多层面CT重建诊断中央大气道良性病变   总被引:7,自引:0,他引:7  
目的 :分析多层面CT三维重建诊断中央大气道良性病变的价值。材料和方法 :用多层面CT对 3 5例中央气道良性病变 (解剖性异常 5例 ,炎症性病变 18例及其它 12例 )扫描 ,并全部完成三维表面遮盖显示、容积显示和仿真内窥镜检查。所有病例第一次读片时仅有横断面图像 ,第二次读片时增加重建图像。结果 :三维重建帮助 4例横断面漏误诊的解剖性异常获得确诊 ,16例炎症性病变进一步详细显示 ,2例气管支气管裂伤明确范围和程度 ;虚拟内窥镜帮助 5例横断面上不能确诊的痰液获得确诊。结论 :CT三维重建可用于解剖性异常和痰液的诊断 ,对其它良性疾病主要是对病变的另一种形式的进一步显示。  相似文献   
72.
心脏瓣膜置换术后中远期疗效分析   总被引:8,自引:0,他引:8  
目的 分析探讨心脏瓣膜置换术的中远期疗效。方法  1978年至 2 0 0 1年 12月 ,行瓣膜置换手术 2 14 1例 ,同期随访 16 81例 ,计 80 2 1 1人·年 ,平均 4 77人·年。通过回顾病因、手术方式、瓣膜类型等因素 ,观察术后病人心功能改善情况 ,病死率及并发症等 ,采用t检验 ,多因素回归等统计学方法分析。结果  92例死亡。总体生存率 5年为 (92 3± 2 2 ) % ,10年生存率为 (90 1± 2 7) %。并发症有血栓栓塞、机械瓣膜功能障碍、瓣周漏、溶血、机械瓣膜感染性心内膜炎。术后心功能 (NYHA)与术前比较有明显的提高。结论  1.机械瓣置换术后中远期疗效满意 ,病死率及并发症均较低 ;与术前心功能和手术种类直接相关 ;2 .使用保留瓣下结构及三尖瓣成形术对术后心功能恢复有明显效果 ;3.术中良好心肌保护是提高手术成功率的关键。  相似文献   
73.
本文从信息经济学的角度出发,分析了病案信息的经济价值、市场需求及其开发利用,揭示了病案信息利用对相关市场参与者的利润、效用、福利增进的机制及在疾病控制中的重大作用,指明了加强病案信息开发的重要性和紧迫性,并提出建议。  相似文献   
74.
The pattern of gastro-intestinal (GIT) and Respiratory tract (RTI) diseases in rural areas of the Varanasi district, U.P. (India) was studied from the outpatient (OPD) attendance between July 1985 to June 1986. Out of a total of new patients, 19.71% had respiratory diseases in contrast to 27.9% with GIT disease. A decreasing trend was observed in attendance rates as age advanced. The difference in age distribution of males and females was statistically significant. The attendance rates for GIT diseases were higher in female (29.16%) than in males (25.16%) whereas in RTI, the rates were higher in males (19.39%) than in females (18.77%). The attendance rate was found to be higher in rainy season (23.59%) followed by summer (14.50%). Diarrhoea (15.44%) and upper (URTI) respiratory tract infection (19.93%) occupied the major recorded episodes.  相似文献   
75.
Objectives
To explore medical students' use of computer tutorials embedded in a busy clinical setting; to demonstrate that such tutorials can increase knowledge gain over and above that attributable to the clinical rotation itself.
Methods
Six tutorials were installed on a computer placed in a central area in an emergency department. Each tutorial was made up of between 33 and 85 screens of information that include text, graphics, animations, and questions. They were designed to be brief (10 minutes), focused, interactive, and immediately relevant. The authors evaluated the intervention using quantitative research methods, including usage tracking, surveys of faculty and students, and a randomized pretest-posttest study.
Results
Over 46 weeks, 95 medical students used the tutorials 544 times, for an overall average of 1.7 times a day. The median time spent on completed tutorials was 11 minutes (average [SD], 14 [±12] minutes). Seventy-four students completed the randomized study. They completed 65% of the assigned tutorials, resulting in improved examination scores compared with the control (effect size, 0.39; 95% confidence interval = 0.15 to 0.62). Students were positively disposed to the tutorials, ranking them as "valuable." Fifty-four percent preferred the tutorials to small group teaching sessions with a preceptor. The faculty was also positive about the tutorials, although they did not appear to integrate the tutorials directly into their teaching.
Conclusions
Medical students on rotation in a busy clinical setting can and will use appropriately presented computer tutorials. The tutorials are effective in raising examination scores.  相似文献   
76.
闫敬泽  贺恩治 《实用医技杂志》2007,14(14):1867-1867
在临床病理手术切除中甲状腺疾病很常见,其疾病的良恶性鉴别和具体类型诊断有一定难度。因甲状腺疾病的病因复杂,有多病变并存现象,且密切相关、相互影响,如何合理准确地进行病理诊断是指导临床治疗和随诊的重要依据。现将我科2002年1月至2004年12月91例甲状腺病理活检材料进行回顾性分析,以进一步提高甲状腺疾病诊断和鉴别诊断水平。  相似文献   
77.
Summary— Experimental and clinical data clearly demonstrate that calcium antagonists (CA) may have an action on the central nervous system (CNS). The cerebrovascular action of CA justifies their use in cerebral ischaemia, vasospasm and hypoxia. Several clinical trials have demonstrated such beneficial effects. On the other hand a number of reports indicate that CA may have a direct neuronal effect, although most of such trials have not been verified or are mere case reports. In addition, the large number of conditions susceptible to being corrected by CA is impressive: epilepsy, pain, dystonia, dyskinesia, psychiatric conditions, etc. Other papers are disconcerting that report extrapyramidal disorders induced by flunarizine and cinnarizine in the elderly, whereas nicardipine does not produce such side effects and may even alleviate some parkinsonian symptoms. In various experimental models (e.g. stroke, oedema), pharmacological effects have been shown to vary from one compound to the other. Two main questions are yet to be answered: 1) has the direct neuronal effect of CA been clearly established? 2) are the multiple clinical effects on the CNS really linked to calcium antagonism?  相似文献   
78.
Epstein-Barr virus (EBV) was inoculated into two species of marmosets. Successful infection was established in the majority of the animals of one species, Callithrix jacchus, as evidenced by the development of high, persistent levels of antibody against virus-specific capsid and early nonstructural proteins. Antibodies also were produced against the major membrane antigen and, in some animals, against EBV nuclear antigen (EBNA) 2 but not against EBNA 1. This is the antibody profile normally noted in individuals with chronic infectious mononucleosis (IM). EBV-induced lymphoproliferation was not seen, and EBV-specific proteins were not detected in the peripheral blood lymphocytes of infected animals. Hence, EBV infection in C. jacchus apparently does not generally include extensive B-cell involvement. However, the marmosets clearly are useful as a model for EBV primary infection and also possibly for chronic IM.  相似文献   
79.
Epidemiological study of myasthenia gravis in Sardinia, Italy (1958–1986)   总被引:2,自引:0,他引:2  
From 1.1.1958 to 31.12.1986, 110 cases of MG were observed in Sardinia, with a mean annual incidence of 2.5 x 1,000,000 inhabitants and prevalence rates of 7.5, 17.6, 31.4 and 45.0 x 1,000,000 inhabitants respectively (prevalence days: 15.10.1961, 24.10.1971, 25.10.1981 and 31.12.1986). The disease was found to be more frequent in women. There were no differences in the distribution of MG in various areas of the island. The muscle group more frequently involved at onset was the ocular. In 6.4% of patients an association with thyroid disorders was observed. The mortality of MG patients was significantly higher than expected. Removal of the thymus, carried out in 58 patients, was shown to be useful in the treatment of the disease, particularly in patients without thymomas. No familial cases were observed.  相似文献   
80.
871例干部体检的X线胸片分析结果表明:正常者254例,正常率仅29.2%,且随年龄的增长而降低。主要病变有慢性支气管炎、主动脉增宽与迂曲,而且还发现了3例肺癌,说明胸部平片检查在体检中仍具有重要的意义。  相似文献   
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