全文获取类型
收费全文 | 48442篇 |
免费 | 4879篇 |
国内免费 | 1058篇 |
专业分类
耳鼻咽喉 | 327篇 |
儿科学 | 980篇 |
妇产科学 | 588篇 |
基础医学 | 4728篇 |
口腔科学 | 1593篇 |
临床医学 | 4420篇 |
内科学 | 6271篇 |
皮肤病学 | 563篇 |
神经病学 | 3923篇 |
特种医学 | 1312篇 |
外国民族医学 | 3篇 |
外科学 | 3704篇 |
综合类 | 5190篇 |
现状与发展 | 5篇 |
一般理论 | 2篇 |
预防医学 | 8421篇 |
眼科学 | 653篇 |
药学 | 3614篇 |
30篇 | |
中国医学 | 4711篇 |
肿瘤学 | 3341篇 |
出版年
2024年 | 164篇 |
2023年 | 1101篇 |
2022年 | 1634篇 |
2021年 | 2068篇 |
2020年 | 2013篇 |
2019年 | 1955篇 |
2018年 | 1917篇 |
2017年 | 1875篇 |
2016年 | 1702篇 |
2015年 | 1564篇 |
2014年 | 3464篇 |
2013年 | 3564篇 |
2012年 | 2812篇 |
2011年 | 3020篇 |
2010年 | 2339篇 |
2009年 | 2232篇 |
2008年 | 2526篇 |
2007年 | 2525篇 |
2006年 | 2243篇 |
2005年 | 1851篇 |
2004年 | 1551篇 |
2003年 | 1456篇 |
2002年 | 1139篇 |
2001年 | 1081篇 |
2000年 | 821篇 |
1999年 | 736篇 |
1998年 | 538篇 |
1997年 | 570篇 |
1996年 | 435篇 |
1995年 | 462篇 |
1994年 | 392篇 |
1993年 | 339篇 |
1992年 | 323篇 |
1991年 | 283篇 |
1990年 | 247篇 |
1989年 | 216篇 |
1988年 | 204篇 |
1987年 | 164篇 |
1986年 | 138篇 |
1985年 | 141篇 |
1984年 | 113篇 |
1983年 | 76篇 |
1982年 | 78篇 |
1981年 | 69篇 |
1980年 | 67篇 |
1979年 | 33篇 |
1978年 | 35篇 |
1977年 | 27篇 |
1976年 | 20篇 |
1975年 | 20篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
目的 : 海岛学生饮食结构中含有碘丰富的海产品。本研究旨在了解海岛学生的碘营养状况 ,评价食盐补碘的利弊。方法 : 对定海农村 (食用碘盐 )和岱山农村 (不食用碘盐 )的学校中随机抽取的 1 2个班级 ,对碘盐组和非碘盐组的饮食碘摄入和尿碘水平等变量进行描述 ,并分别以尿碘和甲状腺肿率为应变量进行单因素和多因素回归分析。结果 : 碘盐组除碘盐外每日碘摄入量中位数为 1 84μg,而不食用加碘盐的组为 1 0 5 μg,两组饮食碘摄入有显著性差异 (u=4.71 0 ,P=0 .0 0 0 ) ,而尿碘水平在食用碘盐组和不食用碘盐组分别为 1 6 9μg/L和 1 2 9μg/L,两组间有显著性差异 (u=6 .3 0 2 ,P=0 .0 0 0 )。多因素分析中性别和是否食用碘盐对尿碘水平有显著性意义 (P<0 .0 5 ,OR值分别为 0 .76 5 ,1 .93 3 )。甲状腺肿学生和正常学生的饮食碘和尿碘无统计学差异 (P>0 .0 5 )。Poisson回归分析中性别和是否食用碘盐对甲状腺肿率有影响 (P<0 .0 5 ,OR值分别为2 .2 5 ,3 .5 2 )。结论 : 舟山海岛学生要注意补碘过程中可能出现的碘过量问题。 相似文献
32.
Several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, Carassius auratus. These were visualized by retrograde transport of horseradish peroxidase (HRP) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25gh segments of the vertebral column. As many as 16 brain nuclei or neuronal aggregations and the Mauthner cells project posteriorly up to the 20th spinal segment. Restricted neurons of the dorsolateral area in the nucleus preopticus magnocellularis and those of the ventromedial nucleus of the thalamus projected up to the 20th and 25th segments respectively. In the mesencephalon, the nucleus ruber and the nucleus of the medial longitudinal fasciculus revealed retrogradely labeled somata; the former extended up to the 20th segment, while the latter projected up to the 25th segment. The remaining descending projected neurons of the brain belonged to the rhombencephalon. The nucleus of the lateral lemniscus; anterior, magnocellular, descending and posterior divisions of the octaval nucleus: raphe nucleus; Mauthner cell and the neurons located adjacent to the trigeminal tract and those in the vicinity of the secondary gustatory tract sent their processes up to 20th segmental level. However, somata of the superior, medial and inferior divisions of the reticular nucleus and restricted neurons of the facial lobe extended up to 25th segmental level. The pattern of neuronal projections into the spinal cord suggests a topographic organization. 相似文献
33.
The morphological changes produced in the thyroid glands of albino rats following radiation with a 904 nm infrared laser were studied. Two different levels of radiation were applied: 46.8 J/cm2 and 140.4 J/cm2. Evaluation of the changes in the densities of the epithelial, colloidal and follicular volumes and of the activation index revealed that the laser beam produced changes in the thyroid parenchyma. It was observed that there was a direct relationship between the severity of the lesion and the radiation energy applied. 相似文献
34.
测定72例健康老年人(60-84岁)和65例健康青中年人(20-50岁)血清和尿β2微球蛋白(β2m),发现前血清β2m浓度比后明显增高(p<0.001);老年组≥70岁尿液β2m浓度也明显增高(p<0.05)。结果表明肾小球滤过率下降随年龄增长而降低,以后再出现肾小管功能减退。本试验较血清尿素氮、肌酐和内生肌酐清除率测定更为敏感。 相似文献
35.
抑郁障碍患者人格特征与发病关系的研究 总被引:7,自引:3,他引:4
目的探讨抑郁障碍患者的人格特征与其疾病发病间的关系。方法采用自评抑郁量表(SDS)、艾森克人格问卷 (EPQ)、应对方式评定量表 (WCRS)和归因方式问卷 (ASQ)对 76名抑郁障碍患者进行测试 ,同时选取 84名健康被试进行对照研究。结果①抑郁组患者在EPQ中神经质 (N)与精神质 (P)的得分显著高于健康组。②WCRS的结果显示在“宣泄接纳”、“退避调节”两个因子上 ,抑郁组的平均得分低于健康组。③在ASQ的得分中 ,抑郁组在负性事件归因的自身性、持久性和整体性均显著高于健康组。④抑郁障碍患者的“神经质”人格特质与应对方式的“宣泄接纳”和“退避调节”因子呈负相关 (r = 0 .474)。结论抑郁障碍患者的人格特征可表现为较强的神经质及孤僻、交往障碍 ,他们这种人格特征及应对和归因方式在其发病过程中起着重要作用。 相似文献
36.
Christopher L. Knight MD Henry A. Sakowski MD Bruce L. Houghton MD Mary B. Laya MD MPH Dawn E. DeWitt MD MSc 《Journal of general internal medicine》2004,19(5P2):594-598
The World Wide Web creates new challenges and opportunities for medical educators. Prominent among these are the lack of consistent standards by which to evaluate web-based educational tools. We present the instrument that was used to review web-based innovations in medical education submissions to the 2003 Society of General Internal Medicine (SGIM) national meeting, and discuss the process used by the SGIM web-based clinical curriculum interest group to develop the instrument. The 5 highest-ranked submissions are summarized with commentary from the reviewers. 相似文献
37.
关于中医证候研究的几点想法 总被引:21,自引:5,他引:16
中医证候学研究是目前中医药研究工作的前沿领域.近年来,虽从不同的角度取得了一些进展,但就本质而言,依旧没有明显的突破.虽然证候的传统定义是基本清楚的,但证候的宏观(定性)标准不十分规范,证候宏观(定性)标准量化研究方法有待统一.这在很大程度上阻碍了整个中医药现代化的进程,因此,证候的现代研究思路值得进一步探讨.在证候研究过程中,建议:(1)以现代疾病为切入点,从基本证候(单证)着手,逐步向复证研究过渡;(2)以人为研究对象,取得相当成果后再进行动物实验才有意义;(3)不仅要与生命科学接轨,更要与整个的自然科学接轨. 相似文献
38.
39.
V W Ansanelli 《Lasers in surgery and medicine》1986,6(5):470-472
Review of the literature reveals little to no data regarding the use of the CO2 laser as a surgical modality in the local treatment of breast cancer. This study was undertaken to determine if the CO2 laser is a surgical improvement over the scalpel, influencing patient care during the surgical and postsurgical period. In the author's series, a total of 209 procedures were performed. Within this group, 105 cases were performed with CO2 laser and 104 cases performed with the scalpel. Biopsies were always performed as a separate procedure prior to definitive surgery. This study was not designed to compare cure rates, the medical follow-up period being 1 year. The results of this study demonstrate a significant improvement in patients' postoperative care, surgical technique, and hospital cost-effectiveness. 相似文献
40.
D. Rothenbacher M. Weyermann G. Fantuzzi H. Brenner 《Clinical and experimental allergy》2007,37(8):1143-1149
BACKGROUND: Adipokines are involved in the regulation of many inflammatory processes and are present at very high concentrations in cord blood of term infants. OBJECTIVE: We analysed data of a large prospective birth cohort study to examine whether adiponectin and leptin concentration in cord blood are determinants of wheezing disorders in children within the first 2 years of life. METHODS: Seven hundred and forty mothers and their newborns were included in this analysis. Adiponectin and leptin concentrations were measured in cord blood. The cumulative incidence of physician-reported asthma or obstructive bronchitis was recorded during a 2-year follow-up. RESULTS: During the first 2 years of life, asthma or obstructive bronchitis was reported by the caring paediatricians for 157 (19.6%) of the children. We found a strong interaction of cord blood adiponectin and history of atopic disease in the mother with respect to the risk of physician-reported asthma or obstructive bronchitis (P=0.006). Compared with children with cord blood levels in the middle quintile (reference category), the odds ratios for physician-reported asthma or obstructive bronchitis in the bottom quintile and top quintile were 0.14 [95% confidence interval (CI) 0.02-0.90] and 2.12 (95% CI 0.67-6.66), respectively (P for trend=0.0003), among children of mothers with a history of atopy. This association was independent of other established risk factors. Leptin levels in cord blood were not associated with risk of asthma or obstructive bronchitis. CONCLUSIONS: In children of mothers with a history of atopy, concentrations of adiponectin in cord blood could play an important role in determining risk of wheezing disorders in early childhood. 相似文献