全文获取类型
收费全文 | 2215篇 |
免费 | 151篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 60篇 |
妇产科学 | 25篇 |
基础医学 | 251篇 |
口腔科学 | 47篇 |
临床医学 | 347篇 |
内科学 | 222篇 |
皮肤病学 | 8篇 |
神经病学 | 399篇 |
特种医学 | 52篇 |
外科学 | 185篇 |
综合类 | 312篇 |
现状与发展 | 1篇 |
预防医学 | 120篇 |
眼科学 | 18篇 |
药学 | 169篇 |
中国医学 | 144篇 |
肿瘤学 | 20篇 |
出版年
2023年 | 30篇 |
2022年 | 42篇 |
2021年 | 83篇 |
2020年 | 88篇 |
2019年 | 60篇 |
2018年 | 72篇 |
2017年 | 53篇 |
2016年 | 72篇 |
2015年 | 58篇 |
2014年 | 118篇 |
2013年 | 124篇 |
2012年 | 100篇 |
2011年 | 128篇 |
2010年 | 110篇 |
2009年 | 112篇 |
2008年 | 122篇 |
2007年 | 106篇 |
2006年 | 110篇 |
2005年 | 88篇 |
2004年 | 57篇 |
2003年 | 67篇 |
2002年 | 56篇 |
2001年 | 55篇 |
2000年 | 50篇 |
1999年 | 29篇 |
1998年 | 49篇 |
1997年 | 44篇 |
1996年 | 30篇 |
1995年 | 19篇 |
1994年 | 23篇 |
1993年 | 22篇 |
1992年 | 25篇 |
1991年 | 16篇 |
1990年 | 10篇 |
1989年 | 13篇 |
1988年 | 9篇 |
1987年 | 14篇 |
1986年 | 8篇 |
1985年 | 17篇 |
1984年 | 14篇 |
1983年 | 12篇 |
1982年 | 9篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 8篇 |
1972年 | 4篇 |
1971年 | 5篇 |
排序方式: 共有2406条查询结果,搜索用时 343 毫秒
1.
2.
Fang Xing Xin Fang Xiang-Dan Gong Xin Zhao Ying Du Zheng-Liang Ma Xiao-Ping Gu Tian-Jiao Xia 《中国神经再生研究》2020,(6):1094-1101
Sleep-wake rhythm disturbances,which are characterized by abnormal sleep timing or duration,are associated with cognitive dysfunction.Photoacoustic treatments including light and sound stimulation have been found to be effective in modulating sleep patterns and improving cognitive behavior in abnormal sleep-wake pattern experiments.In this study,we examined whether light and sound interventions could reduce sleep-wake pattern disturbances and memory deficits in a sleep rhythm disturbance model.We established a model of sleep rhythm disturbance in C57 BL/6 J mice via a sleep deprivation method involving manual cage tapping,cage jostling,and nest disturbance.We used a Mini Mitter radio transmitter device to monitor motor activity in the mice and fear conditioning tests to assess cognitive function.Our results indicated that an intervention in which the mice were exposed to blue light(40-Hz flickering frequency)for 1 hour during their subjective daytime significantly improved the 24-hour-acrophase shift and reduced the degree of memory deficit induced by sleep deprivation.However,interventions in which the mice were exposed to a 40-Hz blue light at offset time or subjective night time points,as well as 2 Hz-blue light at 3 intervention time points(subjective day time,subjective night time,and offset time points),had no positive effects on circadian rhythm shift or memory deficits.Additionally,a 2000-Hz sound intervention during subjective day time attenuated the24-hour-acrophase shift and memory decline,while 440-Hz and 4000-Hz sounds had no effect on circadian rhythms.Overall,these results demonstrate that photoacoustic treatment effectively corrected abnormal sleep-wake patterns and cognitive dysfunction associated with sleep-deprivation-induced disturbances in sleep-wake rhythm.All animal experiments were approved by the Experimental Animal Ethics Committee of Drum Tower Hospital Affiliated to the Medical College of Nanjing University,China(approval No.20171102)on November20,2017. 相似文献
3.
《Sleep medicine》2020
BackgroundTo date, no previous studies have evaluated the relationship between sleep duration and quality of life (QOL) or depression in the general population after controlling for daytime sleepiness and sleep disturbances.MethodsA web-based cross-sectional survey was conducted with 8698 subjects aged 20–69 years. We examined the relationships between weekday sleep duration and daytime sleepiness, sleep disturbance, QOL and depression, using the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (without the item for sleep duration), 8-item Short Form and Center for Epidemiological Studies Depression Scale (CES-D).ResultsDaytime sleepiness tended to increase in proportion to shorter weekday sleep durations. Sleep disturbances, physical and mental QOL, and CES-D scores were worse in both the shorter and longer sleep groups compared with the group with 7–8 h of sleep. Hierarchical logistic regression analyses revealed that short sleep duration but not long sleep duration was significantly associated with reduction of both physical and mental QOL, even after controlling for the presence of daytime sleepiness and sleep disturbance. Both short and long sleep duration were independently and significantly correlated with depression after controlling for daytime sleepiness; however, there was no statistically significant association after adjusting for the effects of sleep disturbance.ConclusionsThe results suggested adverse effects of short sleep but not long sleep on both physical and mental QOL. In addition, the negative impact of specific types of sleep disturbance on depression may be greater than the impact of shortening of sleep duration. 相似文献
4.
《Sleep medicine》2020
Study objectivesTo analyze the association between sleep-related symptoms and sleep length in parents and their children in relation to other risk factors in both generations.MethodThe participants were parents (n = 5,855, age 54.3 ± 6.5 years, 45.2% men) who participated in the community-based Respiratory Health in Northern Europe (RHINE) study and one random member of their adult offspring (n = 5,855, age 30.2 ± 7.7 years, 41.5% men) who participated in the Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) study. Both generations responded to identical questionnaires on sleep symptoms, including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), snoring, nocturnal sweating, nocturnal gastroesophageal reflux (nGER), sleep time and excessive daytime sleepiness (EDS). Insomnia was defined as either, or both, DIS and DMS in combination with EDS.ResultsAll sleep variables except nocturnal sweating were more common in offspring whose parents had reported the same symptom. After adjusting for age, gender, BMI, smoking, physical activity, education, center and parents' total number of children, there were independent associations between sleep symptoms in parents and offspring for DIS (adj. OR, 95% CI: 1.52, 1.20–1.93), DMS (1.34, 1.15–1.56), snoring (1.45, 1.15,1.83), nGER (1.65, 1.15–2.37), insomnia (1.39, 1.13–1.73), short sleep time (<6 h/night) (2.51, 1.72–3.68) and EDS (1.48, 1.26,1.72). There were no independent relationships between symptoms in parents and offspring for EMA, nocturnal sweating or long sleep time (>9 h/night).ConclusionThe familiar aggregation of many sleep disturbances was not explained by investigated lifestyle and environmental factors. This supports a heritable factor in sleep problems. 相似文献
5.
目的 了解电化学杀菌过程中副产物三氯甲烷的生成因素。方法 取滤后水 (三层滤料快滤池后、投放液氯前 )分别以石墨、Ti(基 ) - Ti为电极 ,配制不同 SO42 - 和 Cl- 浓度的实验水样 ,调节不同槽电流密度 ,电解不同时间后 ,取样分析 ,考察在不同条件下 CHCl3 的产生情况。结果 采用 Ti(基 ) - Ti电极的间歇电解过程中产生的 CHCl3 比采用石墨电极时多 ,且电流密度越大 ,产生的 CHCl3 越多。加入微量电解质 Na2 SO4对 CHCl3 的产生量无显著影响 ;加入微量电解质 Na Cl,〔CHCl3 〕随〔Cl- 〕的增大而增大。结论 在饮用水电解杀菌时应采用石墨电极 ,电解时间不宜超过 10分钟 ,电流密度宜 1m A/ cm2 ,以使 CHCl3 的生成量最小 相似文献
6.
地塞米松对扩张皮瓣血运障碍的救治 总被引:7,自引:2,他引:5
目的寻求扩张皮肤Ⅱ期手术形成皮瓣时出现血运障碍及防止坏死的有效治疗方法。方法皮瓣出现血运障碍时,立即静脉给予地塞米松0.4mg/kg,然后逐渐减量,术后6d停药。10d时观察判断皮瓣成活情况。结果35例出现血运障碍的皮瓣,经救治完全成活33例,大部分成活2例。成活后皮瓣色泽、弹性均好。结论及时用地塞米松是防止扩张皮瓣出现血运障碍及坏死的良好方法。 相似文献
7.
目的对比观察乳酸钠林格液和万汶在术前急性扩容性血液稀释前后电解质的变化。方法20例病人随机分为万汶组(组1)和乳酸钠林格液组(组2)。病人入室开放静脉后分别给予两组液体15 ml/kg,30 min输注完毕。分别于输液前后抽血查血常规、电解质。结果两组扩容前后MAP、HR无明显变化,血K+稀释性降低。组1扩容后HCT下降明显,血Na+明显增加,但仍在正常范围之内。组2扩容后HCT明显下降,血Na+在正常范围之内。结论万汶扩容效果优于乳酸钠林格液,但可致血Na+升高,血K+稀释性降低。 相似文献
8.
Background: The occurrence of benign bone cysts adjacent to an active physis may be associated with a physeal arrest. That arrest may result from physeal penetration of the cysts itself, secondary pathologic fracture or the result of surgical curettage. Methods : The pre-treatment X-rays of patients attending the Bone Tumor Clinic at the Children's Hospital and Medical Center were reviewed. Those patients presenting with a bone cyst were identified and the affected side was compared to the normal side in order to determine growth discrepancies. Results: Three cases of benign bone cysts are presented that were located adjacent to a growing physis and produced growth disturbance in the absence of surgical intervention. Conclusions: The risk of growth disturbance in itself should not be a contraindication to surgical intervention. 相似文献
9.
[目的]探索不安障碍治疗的有效途径。[方法]采用中药结合心理干预治疗不安障碍患者40例。[结果]显效31例(77·5%)、有效7例(17·5%)无效2例(5·0%)。SDS、CMI有显著性差异。[结论]中药结合心理干预治疗不安障碍疗效显著。 相似文献
10.
目的 提高对肾移植术后并发大腿感觉功能障碍的认识水平。方法 对179例肾移植术后患者进行问诊和大腿皮肤针刺检查。结果 179例中发现28例存在手术侧大腿感觉功能障碍。其中78例移植肾动脉与髂内动脉吻合的患者中有11例,分别为大腿前面7例、外侧面2例、前面和外侧面2例:101例移植肾动脉与髂外动脉吻合的患者中有17例,分别为大腿前面13例、外侧面1例、前面和外侧面3例。除1例为持续性感觉功能障碍外,其余27例均在术后半年内自愈。结论 肾移植术后出现手术侧大腿皮肤感觉功能障碍是较常见的并发症。肾移植术前应告知患者可能出现这种并发症。 相似文献