首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   22946篇
  免费   2177篇
  国内免费   611篇
耳鼻咽喉   406篇
儿科学   236篇
妇产科学   787篇
基础医学   3430篇
口腔科学   187篇
临床医学   2886篇
内科学   1718篇
皮肤病学   118篇
神经病学   8782篇
特种医学   457篇
外科学   1965篇
综合类   1730篇
预防医学   563篇
眼科学   194篇
药学   1504篇
  5篇
中国医学   640篇
肿瘤学   126篇
  2023年   491篇
  2022年   633篇
  2021年   1108篇
  2020年   1176篇
  2019年   987篇
  2018年   913篇
  2017年   941篇
  2016年   794篇
  2015年   774篇
  2014年   1372篇
  2013年   1497篇
  2012年   1042篇
  2011年   1228篇
  2010年   973篇
  2009年   994篇
  2008年   1010篇
  2007年   943篇
  2006年   918篇
  2005年   762篇
  2004年   668篇
  2003年   649篇
  2002年   561篇
  2001年   411篇
  2000年   364篇
  1999年   325篇
  1998年   250篇
  1997年   241篇
  1996年   201篇
  1995年   225篇
  1994年   237篇
  1993年   178篇
  1992年   241篇
  1991年   193篇
  1990年   194篇
  1989年   177篇
  1988年   144篇
  1987年   144篇
  1986年   138篇
  1985年   228篇
  1984年   202篇
  1983年   152篇
  1982年   162篇
  1981年   148篇
  1980年   141篇
  1979年   122篇
  1978年   98篇
  1977年   76篇
  1976年   79篇
  1975年   47篇
  1974年   51篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
目的探讨短时程脊髓电刺激(temporary spinal cord stimulation, tSCS)治疗爆发痛合并触诱发痛的急性期带状疱疹的临床疗效。方法回顾性地分析同济大学附属第十人民医院疼痛科2020年1月—2020年12月收治的52例接受tSCS治疗的爆发痛合并触诱发痛的急性期带状疱疹患者的临床资料,评估在治疗前、治疗后3d、7d、14d、3个月、6个月的总体疼痛情况(numerical rating scale, NRS)评分、(simple McGill scores, McGill)评分、爆发痛情况(发生率、NRS评分、次数以及持续时间)、触诱发痛情况(发生率、分级)、术后不良反应等;评估在治疗前、治疗后7d、3个月、6个月的睡眠时长、睡眠中醒来次数、疼痛障碍指数(pain disorder index, PDI)、功能状态评分(Karnofsky score, KPS)、抑郁症筛查量表(patient health questionnaire depression module scale, PHQ-9)和焦虑症筛查量表(generalized anxiety disorder-7 scale, GAD-7)等。结果与治疗前相比,治疗后3d、7d、14d、3个月、6个月的总体疼痛NRS评分、总体疼痛MCGILL评分、静息痛NRS评分明显降低(均P<0.001);与治疗前相比,治疗后3d、7d、14d、3个月、6个月的的爆发痛NRS评分明显降低(均P<0.05),治疗后14d、3个月、6个月时的爆发痛次数以及持续时间都明显降低(均P<0.05);与治疗前比较,患者治疗后7d、14d、3个月、6个月时的触诱发痛的分级都明显降低,差异均有统计学意义(均P<0.05);与治疗前相比,治疗后14d、3个月、6个月的PDI评分明显降低(P<0.05);与治疗前相比,治疗后14d、3个月、6个月的PHQ-9评分和GAD-7评分都明显减少(P<0.05),与术前的药物使用情况相比,治疗后各镇痛药使用人数普遍呈下降趋势;术中及整个随访期间未观察到严重不良事件。结论短时程脊髓电刺激对爆发痛合并触诱发痛的急性期带状疱疹具有较好的临床疗效。  相似文献   
2.
《Brain stimulation》2019,12(5):1271-1279
BackgroundThe use of repetitive transcranial magnetic stimulation (rTMS) as both therapeutic and experimental tools has grown enormously over the past decade. However, variability in response to rTMS is one challenge that remains to be solved. Estrogen can impact neural plasticity and may also affect plastic changes following rTMS. The present study investigated whether estrogen levels influence the neurophysiological effects of high-frequency (HF) rTMS in the left dorsolateral prefrontal cortex (DLPFC).HypothesisIt was hypothesised that individuals with higher endogenous estrogen would demonstrate greater rTMS-induced changes in cortical reactivity.Methods29 healthy adults (15M/14F) received HF-rTMS over left DLPFC. Females attended two sessions, one during a high-estrogen (HE) phase of the menstrual cycle, another during a low-estrogen (LE) phase. Males attended one session. Estrogen level was verified via blood assay. TMS-EEG was used to probe changes in cortical plasticity and comparisons were made using cluster-based permutation statistics and Bayesian analysis.ResultsIn females, a significant increase in TMS-evoked P60 amplitude, and decrease in N45, N100 and P180 amplitudes was observed during HE. A less pervasive pattern of change was observed during LE. No significant changes in TEPs were seen in males. Between-condition comparisons revealed higher likelihood of the change in N100 and/or P180 being larger in females during HE compared to both females during LE and males.ConclusionsThese preliminary findings indicate that a greater neuroplastic response to prefrontal HF-rTMS is seen in women when estrogen is at its highest compared to men, suggesting that endogenous estrogen levels contribute to variability in response to HF-rTMS.  相似文献   
3.
《Brain stimulation》2019,12(4):858-867
BackgroundHigh frequency Deep brain stimulation (DBS) targeting motor thalamus is an effective therapy for essential tremor (ET). However, conventional continuous stimulation may deliver unnecessary current to the brain since tremor mainly affects voluntary movements and sustained postures in ET.ObjectiveWe aim to decode both voluntary movements and the presence of postural tremor from the Local field potentials (LFPs) recorded from the electrode implanted in motor thalamus for stimulation, in order to close the loop for DBS so that stimulation could be delivered on demand, without the need for peripheral sensors or additional invasive electrodes.MethodsLFPs from the motor thalamus, surface electromyographic (EMG) signals and/or behavioural measurements were simultaneously recorded in seven ET patients during temporary lead externalisation 3–5 days after the first surgery for DBS when they performed different voluntary upper limb movements. Nine different patients were recorded during the surgery, when they were asked to lift their arms to trigger postural tremor. A machine learning based binary classifier was used to detect voluntary movements and postural tremor based on features extracted from thalamic LFPs.ResultsCross-validation demonstrated that both voluntary movements and postural tremor can be decoded with an average sensitivity of 0.8 and false detection rate of 0.2. Oscillatory activities in the beta frequency bands (13–23 Hz) and the theta frequency bands (4–7 Hz) contributed most to the decoding of movements and postural tremor, respectively, though incorporating features in different frequency bands using a machine learning approach increased the accuracy of decoding.  相似文献   
4.
Clomiphene citrate (CC) is commonly used off‐label for the treatment of male infertility, yet there is limited data to guide patient selection. To identify a subset of patients more likely to benefit from CC, we aimed to define predictors of improvement in semen parameters among men receiving CC. We retrospectively analysed 151 men treated with at least 25 mg CC daily for male infertility and/or hypogonadism at two institutions between 2004 and 2014. Men previously on testosterone were excluded. The primary outcome was change in semen parameters. Variables included baseline patient characteristics, pre‐treatment hormone profiles and pre‐treatment semen analyses. A total of 77 men met inclusion criteria. Median length of therapy was 2.8 months. There was significant improvement in sperm concentration (14–21 million/ml; p = 0.002) and total motile count (TMC; 13–28 million; p = 0.04). One third of patients who began with fewer than 5 million motile spermatozoon improved to a TMC > 5 million, increasing reproductive options to include intrauterine insemination. Patient characteristics, pre‐treatment hormone profile and degree of oligozoospermia did not predict treatment response. While no predictors of improvement were identified, clinically useful response rates are described for use in shared decision‐making.  相似文献   
5.
6.
目的了解天津市部分老年高知人群轻度认知功能障碍(MCI)现况及其影响因素。方法采用蒙特利尔认知评估问卷(MoCA),对天津市某三甲医院体检中心来院体检的2105名老年高知人群进行问卷调查,并应用单因素及多元logistic回归分析轻度认知功能障碍的影响因素。结果 2105名天津老年高知人群平均MoCA得分为26.81±1.85,MCI检出402人,检出率为19.10%;单因素分析结果显示,性别(χ~2=21.23,P0.01)和甘油三酯异常(χ~2=5.84,P0.05)对老年人MCI的检出均有影响;多因素logistic回归分析显示,女性(OR=0.29,95%CI:0.42~0.70)、未饮用葡萄酒(OR=0.63,95%CI:0.40~0.99)、甘油三酯异常(OR=1.34,95%CI:1.09~1.71)进入回归模型(P0.05)。结论影响天津市老年高知人群MCI检出的因素中女性、未饮用葡萄酒是保护因素,甘油三酯异常是危险因素,可针对影响因素进行有针对性的预防。  相似文献   
7.
Objectives: Amnestic mild cognitive impairment (aMCI) often corresponds to the prodromal stage of Alzheimer disease (AD). The aMCI stage represents a crucial time window to apply preventive interventions in an attempt to delay cognitive decline. Stress, one of AD’s modifiable risk factors frequently co-occurring with aMCI, stands out as a key intervention target. The goal of this study was to assess the impacts of two non-pharmacological interventions, mindfulness and psychoeducation, on stress at the psychological and physiological levels among aMCI older adults.

Methods: Forty-eight aMCI participants were randomized between a mindfulness-based intervention (MBI) and a psychoeducation-based intervention (PBI) for eight weekly sessions. Anxiety symptoms, perceived stress levels, cortisol awakening response (CAR), and coping strategies were assessed pre- and post-intervention. Mindfulness attitudes and time dedicated to at-home meditative practices were evaluated in the MBI group.

Results: The main results revealed a slight reduction of the CAR among MBI participants who practiced meditation at home the most and a decrease in perceived stress levels in the PBI group. Both interventions enhanced problem-focused coping strategies.

Conclusion: In sum, this pilot study supports the potential of MBI and PBI to reduce stress at the physiological and psychological level, respectively, and increase coping strategies in older adults at risk for AD.  相似文献   

8.
9.
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号