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101.
102.
目的 探讨神经系统疾病患者血小板参数的变化。方法 测定神经系统疾病患者血小板数(PLT)和平均血小板体积(MPV),并与对照组作比较。结果 与对照组比较,脑梗死、椎-基底动脉供血不足患者PLT明显减少,MPV明显增大;脑出血组MPV、PLT均减少。结论 血小板参数的变化对神经系统疾病的诊断、预防和治疗有重要的参考价值。 相似文献
103.
Mark C. K. Yang Ronald G. Marks William B. Clark Ingvar Magnusson 《Journal of clinical periodontology》1992,19(2):77-83
Abstract Several statistical models that have been suggested in the periodontal literature for describing longitudinal attachment level changes, such as the gradual loss, single-burst, multiple-burst, and random walk models as well as other models introduced in this paper are compared by their power to predict future attachment loss. The data used in this analysis is from 1061 sites of 8 subjects, with moderate to severe periodontal disease, monitored monthly for about a year. This study found that none of the suggested models could significantly outperform the naive mean predictor, which predicts the future attachment level from the past mean. It was also found that no single model, such as the burst, gradual, or random walk, together with measurement error can fully explain the variation in the data. These results indicate that in the course of one year, the attachment level change may not follow the same model. Consequently, a model that fits well to past data cannot be accurately extended to the future. 相似文献
104.
105.
Martin V. Pusic MD George S. Pachev PhD Wendy A. MacDonald MD 《Academic emergency medicine》2007,14(2):138-148
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
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
106.
107.
一种新型人TNFα对人肝癌裸鼠移植瘤的抗瘤作用 总被引:1,自引:1,他引:0
用人肝癌Bel7402瘤株建立了人肝癌裸鼠移植瘤模型,探讨新型重组人TNFa对这种移植瘤的抗瘤作用,结果表明,rhTFaD11a和原型重组人TNFa的抑瘤率在30%左右时,后者后用的活性产闰数是前者的2倍;两者用量相同时,前者的抑产经比后者提高23个百分 相似文献
108.
目的 探讨HCMV感染是否引起大鼠和家兔胃肠组织损伤。方法 将人巨细胞病毒(Human Cyto—megalovirus,HCMV)AD168毒株静脉接种大鼠和新西兰兔,大鼠90d、兔30d后,检查动物胃、肠组织的病理变化,用免疫组化方法和原位杂交方法检查组织中的病毒抗原和DNA片段。结果 接种病毒之部分动物出现食量减少、粘液性大便,胃粘膜组织可见淋巴细胞浸润,肠粘膜变性坏死,甚至有穿孔灶;在粘膜细胞中查到病毒抗原或DNA片段。结论 HCMV感染可以侵犯动物胃肠组织并引起该组织病理损伤。 相似文献
109.
Soluble CD14 but not interleukin-6 is a new marker for clinical activity in atopic dermatitis 总被引:4,自引:0,他引:4
Summary Levels of soluble IL-2 receptors, IL-6, soluble CD23, soluble CD14 and ECP (eosinophilic cationic protein) were measured as markers of T-cell, B-cell, monocyte and eosinophilic leucocyte activation in 26 patients with atopic dermatitis (AD) on admission to (A) and at discharge from (D) the Department of Dermatology in Zurich. The serum levels of sIL-2R, IL-6, sCD23, sCD14 and ECP were significantly elevated in AD patients in comparison with the normal values of healthy donors. A significant decrease in sIL-2R (p=0.0093) and in sCD14 (p=0.0134) levels was demonstrated between A and D, correlating with the improvement in the skin intensity score (SIS). In addition, a significant correlation of the sCD14 levels and the SIS at A was demonstrated (p=0.0415). These results also incriminate monocytes in the pathogenesis of AD, indicating that, besides sIL-2R and ECP, SCD14 could also be a possible marker for the disease activity. 相似文献
110.
目的 提高对母亲苯丙酮尿症(MPKU)后代脑MRI表现的认识。资料与方法 报告2例生化及临床检查证实为MPKU双胞胎的.MRI改变,并复习文献。结果 文中2例表现与文献报道不一致.与苯丙酮尿症患儿的表现相似。常规T2WI及FLAIR均显示室周白质、侧脑室三角区、半卵圆中心条片状高信号。弥散加权成像(DWI)除更清楚地显示上述改变外,尚显示双侧内囊后肢及胼胝体压部信号增高。结论 常规T2WI及FIJAIR上可显示MPKU后代脑白质异常,DWI可提供更多诊断依据。 相似文献