全文获取类型
收费全文 | 1723篇 |
免费 | 117篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 12篇 |
妇产科学 | 34篇 |
基础医学 | 301篇 |
口腔科学 | 18篇 |
临床医学 | 117篇 |
内科学 | 325篇 |
皮肤病学 | 7篇 |
神经病学 | 434篇 |
特种医学 | 30篇 |
外科学 | 70篇 |
综合类 | 207篇 |
一般理论 | 1篇 |
预防医学 | 35篇 |
眼科学 | 29篇 |
药学 | 160篇 |
2篇 | |
中国医学 | 90篇 |
肿瘤学 | 6篇 |
出版年
2023年 | 15篇 |
2022年 | 21篇 |
2021年 | 60篇 |
2020年 | 53篇 |
2019年 | 48篇 |
2018年 | 55篇 |
2017年 | 29篇 |
2016年 | 51篇 |
2015年 | 49篇 |
2014年 | 91篇 |
2013年 | 103篇 |
2012年 | 94篇 |
2011年 | 68篇 |
2010年 | 77篇 |
2009年 | 80篇 |
2008年 | 78篇 |
2007年 | 84篇 |
2006年 | 48篇 |
2005年 | 50篇 |
2004年 | 55篇 |
2003年 | 35篇 |
2002年 | 59篇 |
2001年 | 39篇 |
2000年 | 32篇 |
1999年 | 35篇 |
1998年 | 33篇 |
1997年 | 26篇 |
1996年 | 22篇 |
1995年 | 13篇 |
1994年 | 24篇 |
1993年 | 20篇 |
1992年 | 26篇 |
1991年 | 19篇 |
1990年 | 13篇 |
1989年 | 18篇 |
1988年 | 18篇 |
1987年 | 12篇 |
1986年 | 25篇 |
1985年 | 30篇 |
1984年 | 30篇 |
1983年 | 22篇 |
1982年 | 27篇 |
1981年 | 23篇 |
1980年 | 22篇 |
1979年 | 17篇 |
1978年 | 13篇 |
1977年 | 10篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1974年 | 4篇 |
排序方式: 共有1886条查询结果,搜索用时 15 毫秒
1.
目的研究冠状动脉慢血流现象(CSFP)患者的危险因素和分析累及冠状动脉病变的特点。方法回顾性收集本院2019年1月—2021年1月因疑似冠心病行冠状动脉造影术的514例患者,分析患者的临床资料、实验室指标及冠状动脉造影结果等相关资料,按照TIMI血流分级分为慢血流组(n=288)和对照组(n=226),比较两组之间的差异,并通过logistics回归分析探讨CSFP患者的危险因素。结果 (1)两组间在性别、民族、吸烟及饮酒史上存在统计学差异(P<0.05)。(2)CSFP组的血红蛋白、游离三碘甲状原氨酸、血肌酐值、血尿酸水平、空腹血糖水平和左室舒张末期大小均高于对照组(P<0.05);而CSFP组的血小板分布宽度、游离甲状腺素、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、载脂蛋白A1和白蛋白水平均低于对照组(P<0.05);(3)CSFP以三支血管病变最多见,为124例(43.0%),而单支血管病变和双支血管病变病例数一样,均为82例(28.5%)。单支血管病变中最多见的是前降支67例(81.7%),其次是右冠状动脉12例(14.6%),左回旋支较少见;(4)多因素logistic回归分析发现:性别、民族、游离甲状腺素、载脂蛋白A1和白蛋白水平是CSFP患者的独立危险因素。结论 (1)男性、少数民族、游离甲状腺素、载脂蛋白A1和白蛋白水平是CSFP的独立危险因素;(2)CSFP更常见于三支冠状动脉病变组,单支冠状动脉病变者更常见于左前降支。 相似文献
2.
《Indian heart journal》2022,74(1):7-12
BackgroundThe relationship of atrial fibrillation (AF) with coronary artery disease (CAD) is well established, yet it is often missed. There is evidence of myocardial ischemia on stress imaging in AF patients in the absence of obstructive CAD. In this prospective cohort, we studied the angiographic profiles of non-valvular AF patients.MethodsThe study was a nonrandomized, prospective, single-center observational study of consecutive patients of persistent non-valvular AF. Patients symptomatic for AF despite optimal medical therapy for 3 months were recruited and all underwent coronary angiograms (CAG). Patients with prior history of CAD were excluded.ResultsA total of 70 patients were followed for a mean duration of 12 ± 1.4 months. The mean age of the study group was 66.07 (±11.49) years. Hypertension was the commonest comorbidity seen in 74% patients. Obstructive CAD was present in 32 (46%) patients, non-obstructive (<50% stenosis) CAD in 17 (24%) patients and normal coronaries in 21 (30%) patients. Overall 49 (70%) patients had evidence of CAD. Amongst patients without obstructive CAD, slow flow was seen in 16 (42%) patients. Lower baseline ejection fraction, lower haemoglobin & albumin levels and higher creatinine levels was associated with increased mortality. In patients without obstructive CAD, hospitalizations for fast ventricular rate were significantly increased in those having slow flow on CAG (p = 0.005).ConclusionsMajority (70%) of our patients had evidence of atherosclerotic CAD on CAG. A large proportion of patients without obstructive CAD had slow flow on CAG. 相似文献
3.
[目的] 应用数据挖掘技术分析安阿玥教授治疗肛瘘术后创面愈合缓慢的用药规律。[方法] 收集2014年7月—2018年6月安阿玥教授收治的肛瘘术后创面愈合缓慢的病例,以“主症、兼症、舌象、脉象、辨证、治法、方药”为项目构建MySQL数据库,利用Python语言搭建分析系统,统计分析获得安阿玥教授治疗肛瘘术后创面愈合缓慢的辨证用药规律。[结果] 共纳入肛瘘术后创面愈合缓慢病例306例,证候多属阴虚内热、气血不足、脾胃不和、热毒内盛、气虚血瘀证,所用方剂多以增液汤、四物汤、青蒿鳖甲汤、半夏泻心汤等加减化裁,用药次数较多的依次为当归、生地、玄参、生黄芪、马齿苋等。[结论] 肛瘘术后创面愈合缓慢以虚证居多,包括阴虚、血虚、气虚等。临床治疗时重视“和血”的辨证思维。数据挖掘技术结果客观反映了安阿玥教授治疗肛瘘术后创面愈合缓慢的临床思路和经验。 相似文献
4.
5.
《Clinical neurophysiology》2020,131(11):2641-2650
ObjectiveTo assess excitability differences between motor and sensory axons of affected nerves in patients with multifocal motor neuropathy (MMN).MethodsWe performed motor and sensory excitability tests in affected median nerves of 20 MMN patients and in 20 age-matched normal subjects. CMAPs were recorded from the thenar and SNAPs from the 3rd digit. Clinical tests included assessment of muscle strength, two-point discrimination and joint position.ResultsAll MMN patients had weakness of the thenar muscle and normal sensory tests. Motor excitability testing in MMN showed an increased threshold for a 50% CMAP, increased rheobase, decreased stimulus-response slope, fanning-out of threshold electrotonus, decreased resting I/V slope, shortened refractory period, and more pronounced superexcitability. Sensory excitability testing in MMN revealed decreased accommodation half-time and S2-accommodation and less pronounced subexcitability. Mathematical modeling indicated increased Barrett-Barrett conductance for motor fibers and increase in internodal fast potassium conductance for sensory fibers.ConclusionsExcitability findings in MMN suggest myelin sheath or paranodal seal involvement in motor fibers and, possibly, paranodal detachment in sensory fibers.SignificanceExcitability properties of affected nerves in MMN differ between motor and sensory nerve fibers. 相似文献
6.
7.
目的研究双重排粪造影方式应用在结肠功能性便秘诊断当中的效果。方法文章所选择的调查对象来自2017年10月-2018年12月,均为在此期间本院收治的60例经临床病理诊断确诊为结肠功能性便秘患者,分析双重排粪造影方式和排粪造影的符合性。结果采用双重排粪造影方式诊断结肠功能性便秘59例得到确诊,占98.33%,和排粪造影相比,差异有统计学意义(P<0.05)。结论通过双重排粪造影方式进行结肠功能性便秘诊断,可以有效的提升诊断的效率,对于具体症型的确认也具有重要意义。 相似文献
8.
Lukas Frase Wolfram Regen Stphanie Kass Albena Rambach Chiara Baglioni Bernd Feige Jürgen Hennig Dieter Riemann Christoph Nissen Kai Spiegelhalder 《Journal of sleep research》2020,29(5)
The current study was designed to further clarify the influence of brain morphology, sleep oscillatory activity and age on memory consolidation. Specifically, we hypothesized, that a smaller volume of hippocampus, parahippocampal and medial prefrontal cortex negatively impacts declarative, but not procedural, memory consolidation. Explorative analyses were conducted to demonstrate whether a decrease in slow‐wave activity negatively impacts declarative memory consolidation, and whether these factors mediate age effects on memory consolidation. Thirty‐eight healthy participants underwent an acquisition session in the evening and a retrieval session in the morning after night‐time sleep with polysomnographic monitoring. Declarative memory was assessed with the paired‐associate word list task, while procedural memory was tested using the mirror‐tracing task. All participants underwent high‐resolution magnetic resonance imaging. Participants with smaller hippocampal, parahippocampal and medial prefrontal cortex volumes displayed a reduced overnight declarative, but not procedural memory consolidation. Mediation analyses showed significant age effects on overnight declarative memory consolidation, but no significant mediation effects of brain morphology on this association. Further mediation analyses showed that the effects of age and brain morphology on overnight declarative memory consolidation were not mediated by polysomnographic variables or sleep electroencephalogram spectral power variables. Thus, the results suggest that the association between age, specific brain area volume and overnight memory consolidation is highly relevant, but does not necessarily depend on slow‐wave sleep as previously conceptualized. 相似文献
9.
Danilo Menicucci Andrea Piarulli Marco Laurino Andrea Zaccaro Jacopo Agrimi Angelo Gemignani 《Journal of sleep research》2020,29(5)
We investigated changes of slow‐wave activity and sleep slow oscillations in the night following procedural learning boosted by reinforcement learning, and how these changes correlate with behavioural output. In the Task session, participants had to reach a visual target adapting cursor's movements to compensate an angular deviation introduced experimentally, while in the Control session no deviation was applied. The task was repeated at 13:00 hours, 17:00 hours and 23:00 hours before sleep, and at 08:00 hours after sleep. The deviation angle was set at 15° (13:00 hours and 17:00 hours) and increased to 45° (reinforcement) at 23:00 hours and 08:00 hours. Both for Task and Control nights, high‐density electroencephalogram sleep recordings were carried out (23:30?19:30 hours). The Task night as compared with the Control night showed increases of: (a) slow‐wave activity (absolute power) over the whole scalp; (b) slow‐wave activity (relative power) in left centro‐parietal areas; (c) sleep slow oscillations rate in sensorimotor and premotor areas; (d) amplitude of pre‐down and up states in premotor regions, left sensorimotor and right parietal regions; (e) sigma crowning the up state in right parietal regions. After Task night, we found an improvement of task performance showing correlations with sleep slow oscillations rate in right premotor, sensorimotor and parietal regions. These findings suggest a key role of sleep slow oscillations in procedural memories consolidation. The diverse components of sleep slow oscillations selectively reflect the network activations related to the reinforced learning of a procedural visuomotor task. Indeed, areas specifically involved in the task stand out as those with a significant association between sleep slow oscillations rate and overnight improvement in task performance. 相似文献
10.
Sabine Gretenkord Bas M. J. Olthof Myrto Stylianou Adrian Rees Sarah E. Gartside Fiona E. N. LeBeau 《The European journal of neuroscience》2020,52(2):2915-2930
The role of dopamine in regulating sleep‐state transitions during, both natural sleep and under anaesthesia, is still unclear. Recording in vivo in the rat mPFC under urethane anaesthesia, we observed predominantly slow wave activity (SWA) of <1 Hz in the local field potential interrupted by occasional spontaneous transitions to a low‐amplitude‐fast (LAF) pattern of activity. During periods of SWA, transitions to LAF activity could be rapidly and consistently evoked by electrical stimulation of the ventral tegmental area (VTA). Spontaneous LAF activity, and that evoked by stimulation of the VTA, consisted of fast oscillations similar to those seen in the rapid eye movement (REM)‐like sleep state. Spontaneous and VTA stimulation‐evoked LAF activity occurred simultaneously along the dorsoventral extent of all mPFC subregions. Evoked LAF activity depended on VTA stimulation current and could be elicited using either regular (25–50 Hz) or burst stimulation patterns and was reproducible upon repeated stimulation. Simultaneous extracellular single‐unit recordings showed that during SWA, presumed pyramidal cells fired phasically and almost exclusively on the Up state, while during both spontaneous and VTA‐evoked LAF activity, they fired tonically. The transition to LAF activity evoked by VTA stimulation depended on dopamine D1‐like receptor activation as it was almost completely blocked by systemic administration of the D1‐like receptor antagonist SCH23390. Overall, our data demonstrate that activation of dopamine D1‐like receptors in the mPFC is important for regulating sleep‐like state transitions. 相似文献