全文获取类型
收费全文 | 22572篇 |
免费 | 1657篇 |
国内免费 | 332篇 |
专业分类
耳鼻咽喉 | 276篇 |
儿科学 | 627篇 |
妇产科学 | 241篇 |
基础医学 | 2136篇 |
口腔科学 | 381篇 |
临床医学 | 3576篇 |
内科学 | 2363篇 |
皮肤病学 | 221篇 |
神经病学 | 5287篇 |
特种医学 | 461篇 |
外科学 | 1433篇 |
综合类 | 2567篇 |
一般理论 | 3篇 |
预防医学 | 2421篇 |
眼科学 | 127篇 |
药学 | 1411篇 |
18篇 | |
中国医学 | 664篇 |
肿瘤学 | 348篇 |
出版年
2023年 | 527篇 |
2022年 | 901篇 |
2021年 | 1397篇 |
2020年 | 1272篇 |
2019年 | 1229篇 |
2018年 | 1216篇 |
2017年 | 1170篇 |
2016年 | 959篇 |
2015年 | 795篇 |
2014年 | 1889篇 |
2013年 | 2073篇 |
2012年 | 1326篇 |
2011年 | 1606篇 |
2010年 | 1048篇 |
2009年 | 1086篇 |
2008年 | 1020篇 |
2007年 | 862篇 |
2006年 | 650篇 |
2005年 | 510篇 |
2004年 | 412篇 |
2003年 | 358篇 |
2002年 | 268篇 |
2001年 | 239篇 |
2000年 | 170篇 |
1999年 | 141篇 |
1998年 | 115篇 |
1997年 | 90篇 |
1996年 | 91篇 |
1995年 | 88篇 |
1994年 | 82篇 |
1993年 | 80篇 |
1992年 | 53篇 |
1991年 | 47篇 |
1990年 | 57篇 |
1989年 | 31篇 |
1988年 | 40篇 |
1987年 | 33篇 |
1985年 | 70篇 |
1984年 | 65篇 |
1983年 | 45篇 |
1982年 | 52篇 |
1981年 | 31篇 |
1980年 | 43篇 |
1979年 | 56篇 |
1978年 | 40篇 |
1977年 | 30篇 |
1976年 | 40篇 |
1975年 | 41篇 |
1974年 | 29篇 |
1973年 | 26篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Alazne Belar Maria Arantzamendi Alfredo Rodríguez-Núñez Yolanda Santesteban Marina Martinez Mario López-Saca Sara Consigli Jesús López-Fidalgo Carlos Centeno 《Journal of pain and symptom management》2019,57(3):627-634
Context
Demoralization is a state of existential distress in patients with advanced illness, typically with coping difficulties, feelings of loss of sense, and purpose in life and despair, among other things. The New Demoralization Scale (DS-II) is an evaluation tool for this syndrome, which has recently been reformulated on a shorter scale.Objectives
The objective of this study was to obtain a Spanish version of the DS-II and to assess its psychometric properties in advanced cancer patients in Spain and a number of Latin American countries.Methods
Following a translation–back translation process, a validation study and a confirmatory analysis using structural equation models with their corresponding latent constructs were undertaken. Patients completed the DS-II in Spanish (DS-II (es)), the Hospital Anxiety and Depression Scale, and the Edmonton Symptom Assessment System–revised. Reliability was studied according to internal consistency; construct validity and concurrent validity with the Hospital Anxiety and Depression Scale and the Edmonton Symptom Assessment System–revised; discriminant validity using the Karnofsky Performance Status scale; and feasibility, with response ratio and required time. Cutoff points were established, and sensitivity and specificity were studied.Results
The DS-II (es) was obtained. One hundred fifty patients completed the validation study. The confirmatory analysis showed coherence, and all items correlated positively with their subscales and with the overall scale. Cronbach's alpha for the DS-II (es) was 0.88, for the sense and purpose subscale 0.83, and for the coping ability 0.79. Demoralization correlated significantly with emotional distress (rho = 0.73, P < 0.001). The tool distinguished between patients with diverse functional levels (rho = ?0.319, P = 0.001). Cutoff points at 10 and 20 out of 32 were established. The scale showed high sensitivity (81.97%) and specificity (80.90%). The prevalence of demoralization was 33% in our sample.Conclusion
The Spanish version of the new Kissane DS-II demoralization scale has shown to be valid, reliable, and feasible with adequate psychometric properties. 相似文献42.
Tau Ming Liew 《Journal of the American Medical Directors Association》2019,20(8):1054.e11-1054.e20
ObjectivesEarly diagnosis of cognitive impairment is increasingly emphasized in the literature to facilitate timely preventive interventions. Although bedside cognitive tests such as the Montreal Cognitive Assessment (MoCA) are widely used for such early diagnostic purposes, they may not have comparable performance to a full neuropsychological battery (FNB) in diagnosing early cognitive impairment. This study investigated whether a small subset of neuropsychological tests can be added on to MoCA to match its performance to that of the FNB in discriminating mild cognitive impairment and dementia (MCI/dementia) from normal cognition.DesignCross-sectional diagnostic study.SettingAlzheimer's Disease Centers across the United States.ParticipantsOlder participants (≥50 years) who completed MoCA and the FNB (N = 9187).MeasuresThe study sample was split into two: the derivation sample (n = 1837) was used to develop a brief neuropsychological battery that best discriminated MCI/dementia (using the best-subset approach with 10-fold cross-validation); while the validation sample (n = 7350) verified its actual performance in discriminating MCI/dementia.ResultsA 3-item neuropsychological battery was identified, comprising MoCA, Benson Complex Figure Recall, and Craft Story 21 Delayed Recall. It had excellent performance in discriminating MCI/dementia from normal cognition (area under the receiver operating characteristic curve [AUROC] 90.0%, 95% confidence interval [CI] 89.2%-90.7%), which was comparable to that of the FNB (AUROC 88.4%, 95% CI 87.6%-89.2%). By contrast, MoCA alone had significantly worse AUROC (86.9%, 95% CI 86.0%-87.7%) than that of the FNB.Conclusions/ImplicationsUsing rigorous methods, this study developed a brief neuropsychological battery that maintained the brevity of a bedside cognitive test, while rivaling the diagnostic performance of an FNB in early cognitive impairment. This brief battery offers a viable alternative when the FNB is needed but cannot be feasibly administered in nonspecialty clinics. It can have a wider health systems effect of improving patients’ access to accurate diagnosis in early cognitive impairment and facilitating timely interventions to delay the progression of cognitive impairment. 相似文献
43.
44.
《The ocular surface》2020,18(2):249-257
PurposeTo evaluate the safety and effectiveness of the intranasal tear neurostimulator (ITN) in improving dry eye symptoms assessed in a controlled adverse environment (CAE®).MethodsStudy 1: Multicenter, subject-masked, randomized-sequence, crossover design. Single intranasal (active) and extranasal (control) ITN administration during CAE exposure. Study 2: Single-arm, open-label design. Intranasal ITN administration ≥2 times/day for 45 days, CAE assessment at days 0 and 45. In both studies, upon CAE entry, and every 5 min thereafter, subjects assessed eye dryness score (visual analog scale, 0–100 mm; EDS-VAS), and ocular discomfort score (ODS; Ora Calibra™, 0–4), for ≈2 h. Study 1: when ODS was ≥3 at 2 consecutive timepoints, subjects applied ITN intranasally or extranasally for ≈3 min, and again when achieving the same ODS criteria in randomized sequence. Study 2: days 0 and 45, ITN was applied for ≈3 min employing the same ODS criteria as Study 1.ResultsStudy 1: Significantly greater pre- to post-application reductions in mean [SEM] EDS (−16.5 [1.7] vs −3.1 [1.7], P < 0.0001) and ODS (−0.93 [0.08] vs −0.34 [0.08], P < 0.0001; n = 143) with intranasal vs extranasal stimulation. Study 2: On day 0 (n = 52) and day 45 (n = 48), significant pre- to post-application reductions in mean [SEM] EDS (−15.9 [2.7] and −15.2 [2.4]; P < 0.0001), and ODS (−1.3 [0.2] and −1.3 [0.1]; P < 0.0001). Few device-related adverse events were reported, none serious.ConclusionsAcute symptom relief is significant with the ITN and remains undiminished after daily use. 相似文献
45.
46.
Rafael Núez Michael Allen Richard Gao Carson Miller Rigoli Josephine Relaford‐Doyle Arturs Semenuks 《Topics in Cognitive Science》2020,12(3):790-803
A recent issue of Topics in Cognitive Science featured 11 thoughtful commentaries responding to our article “What happened to cognitive science?” (Núñez et al., 2019). Here, we identify several themes that arose in those commentaries and respond to each. Crucial to understanding our original article is the fundamental distinction between multidisciplinary and interdisciplinary endeavors: Cognitive science began (and has stayed) as multidisciplinary but has failed to move on to form a cohesive interdisciplinary field. We clarify and elaborate our original argument and reiterate the importance of a data‐driven evaluation of the current status of the field, which exhibits a marked disciplinary imbalance, a lack of a coherent conceptual core, and a striking absence of a consistent curriculum in the institutions that grant degrees in this domain. Half a century after the creation of cognitive science, it may now be a good time to revisit goals and visions for how to best approach the ever‐fascinating scientific study of the mind(s). 相似文献
47.
Ivar R. Kolvoort Soren Wainio‐Theberge Annemarie Wolff Georg Northoff 《Human brain mapping》2020,41(15):4355-4374
The self is a multifaceted phenomenon that integrates information and experience across multiple time scales. How temporal integration on the psychological level of the self is related to temporal integration on the neuronal level remains unclear. To investigate temporal integration on the psychological level, we modified a well‐established self‐matching paradigm by inserting temporal delays. On the neuronal level, we indexed temporal integration in resting‐state EEG by two related measures of scale‐free dynamics, the power law exponent and autocorrelation window. We hypothesized that the previously established self‐prioritization effect, measured as decreased response times or increased accuracy for self‐related stimuli, would change with the insertion of different temporal delays between the paired stimuli, and that these changes would be related to temporal integration on the neuronal level. We found a significant self‐prioritization effect on accuracy in all conditions with delays, indicating stronger temporal integration of self‐related stimuli. Further, we observed a relationship between temporal integration on psychological and neuronal levels: higher degrees of neuronal integration, that is, higher power‐law exponent and longer autocorrelation window, during resting‐state EEG were related to a stronger increase in the self‐prioritization effect across longer temporal delays. We conclude that temporal integration on the neuronal level serves as a template for temporal integration of the self on the psychological level. Temporal integration can thus be conceived as the “common currency” of neuronal and psychological levels of self. 相似文献
48.
49.
Rosacea is a chronic inflammatory disease in face. Hydroxychloroquine (HCQ), an anti-malaria drug, was reported to have anti-inflammation activities. However, the role of HCQ on rosacea remains unclear. In this study, we revealed the potential molecular mechanism by which HCQ improved rosacea in rosacea-like mice and mast cells (MCs). Moreover, the effects of HCQ treatment for rosacea patients were investigated. In this study, we found HCQ ameliorated the rosacea-like phenotype and MCs infiltration. The elevated pro-inflammatory factors and mast cell protease were significantly inhibited by HCQ treatment in rosacea-like mice. In vitro, HCQ suppresses LL37-induced MCs activation in vitro, including the release of inflammatory factors, chemotaxis, degranulation and calcium influx. Moreover, HCQ attenuated LL37-mediated MCs activation partly via inhibiting KCa3.1-mediated calcium signaling. Thus, these evidences suggest HCQ ameliorated rosacea-like dermatitis may be by regulating immune response of MCs. Finally, the 8-week HCQ treatment exerted satisfactory therapeutic effects on erythema and inflammatory lesions of rosacea patients, indicating that it is a promising drug for rosacea in clinical treatment. 相似文献
50.
目的确定我国民航飞行学员飞行训练的应激源。方法采用德尔菲法形成量表初步维度并在此基础上编制初测量表,从不同训练分院及国外训练归校的学员中采取分层随机取样;选取524名飞行学员进行测试,对所得数据进行分析形成正式问卷。对所获数据进行探索性因素分析和验证性因素分析,并分别检验量表的内部一致性系数、重测信度、内容效度与结构效度。结果训练环境、职业前景、飞行教员、座舱环境4个维度共解释了总变异的57.154%。量表总体的Cronbach’sα系数为0.830,各因子的Cronbach’sα系数为0.751~0.782,重测的相关系数均在0.806(P<0.01)以上。维度间的相关系数为0.134~0.438(P<0.05),各维度与总体的相关系数在0.617~0.748(P<0.01)。一阶4因素模型(GFI=0.929、IFI=0.989、TLI=0.986、CFI=0.989、RMSEA=0.013)拟合效果较好。结论民航飞行学员飞行训练应激源量表符合心理测量学标准,具有良好信效度,民航飞行学员飞行训练应激源主要来源于训练环境、职业前景、飞行教员、座舱环境。 相似文献