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81.
Menzies L Ooi C Kamath S Suckling J McKenna P Fletcher P Bullmore E Stephenson C 《Archives of general psychiatry》2007,64(2):156-167
CONTEXT: Cognitive impairment causes morbidity in schizophrenia and could be due to abnormalities of cortical interneurons using the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). OBJECTIVES: To test the predictions that cognitive and brain functional responses to GABA-modulating drugs are correlated and abnormal in schizophrenia. DESIGN: Pharmacological functional magnetic resonance imaging study of 2 groups, each undergoing scanning 3 times, using an N-back working memory task, after placebo, lorazepam, or flumazenil administration. SETTING AND PARTICIPANTS: Eleven patients with chronic schizophrenia were recruited from a rehabilitation service, and 11 healthy volunteers matched for age, sex, and premorbid IQ were recruited from the local community. Intervention Participants received 2 mg of oral lorazepam, a 0.9-mg intravenous flumazenil bolus followed by a flumazenil infusion of 0.0102 mg/min, or oral and intravenous placebo. MAIN OUTCOME MEASURES: Working memory performance was summarized by the target discrimination index at several levels of difficulty. Increasing (or decreasing) brain functional activation in response to increasing task difficulty was summarized by the positive (or negative) load response. RESULTS: Lorazepam impaired performance and flumazenil enhanced it; these cognitive effects were more salient in schizophrenic patients. Functional magnetic resonance imaging demonstrated positive load response in a frontoparietal system and negative load response in the temporal and posterior cingulate regions; activation of the frontoparietal cortex was positively correlated with deactivation of the temporocingulate cortex. After placebo administration, schizophrenic patients had abnormally attenuated activation of the frontoparietal cortex and deactivation of the temporocingulate cortex; this pattern was mimicked in healthy volunteers and exacerbated in schizophrenic patients by lorazepam. However, in schizophrenic patients, flumazenil enhanced deactivation of the temporocingulate and activation of the anterior cingulate cortices. CONCLUSIONS: The GABA-modulating drugs differentially affect working memory performance and brain function in schizophrenia. Cognitive impairment in schizophrenia may reflect abnormal inhibitory function and could be treated by drugs targeting GABA neurotransmission. 相似文献
82.
In the past few decades, rapid improvements in noninvasive optical technologies have revolutionized the diagnosis of early-stage melanoma. Current knowledge and limitations of these tools will be reviewed in this article. Dermoscopy has been recognized as the 'gold standard' in the screening phase. Digital dermoscopy monitoring and total-body photography are used to identify so-called 'featureless' melanoma only on the criteria of change over time. Automated instruments, as well as optical and nonmorphological methods, are still under development, and offer many opportunities to improve the speed and accuracy of the diagnosis of melanoma and/or to reduce the need for expertise. Despite a penetration depth limited to the upper dermis, the quasi-histological imaging achieved by in vivo reflectance confocal microscopy has been demonstrated to significantly aid diagnostic accuracy for selected melanocytic lesions. Future perspectives on diagnostic instrumentation will also be explored. 相似文献
83.
Chamberlain SR Menzies LA Fineberg NA Del Campo N Suckling J Craig K Müller U Robbins TW Bullmore ET Sahakian BJ 《The British journal of psychiatry : the journal of mental science》2008,193(3):216-221
BACKGROUND: Trichotillomania (repetitive hair-pulling) is an Axis I psychiatric disorder whose neurobiological basis is incompletely understood. Whole-brain trichotillomania neuroimaging studies are lacking. AIMS: To investigate grey and white matter abnormalities over the whole brain in patients with trichotillomania. METHOD: Eighteen patients with DSM-IV trichotillomania and 19 healthy controls undertook structural magnetic resonance imaging after providing written informed consent. Differences in grey and white matter were investigated using computational morphometry. RESULTS: Patients with trichotillomania showed increased grey matter densities in the left striatum, left amygdalo-hippocampal formation, and multiple (including cingulate, supplementary motor, and frontal) cortical regions bilaterally. CONCLUSIONS: Trichotillomania was associated with structural grey matter changes in neural circuitry implicated in habit learning, cognition and affect regulation. These findings inform animal models of the disorder and highlight key regions of interest for future translational research. 相似文献
84.
85.
Diana Menzies 《British Journal of Psychotherapy》2001,18(2):227-237
ABSTRACT This paper explores the emergence of hope from hopelessness in an analytic group. It is proposed that hope is an innate feature of every child but that for hope to flourish one's True Self must be known. The experience of being known is described in terms of Stern's subjective self and the sharing of experience. This is then related to the group analytic context and specific features which might allow hope to emerge therein.
The only time I felt hope was when you told me you could see no hope, and you continued with the analysis. 相似文献
The only time I felt hope was when you told me you could see no hope, and you continued with the analysis. 相似文献
86.
87.
Pai M Joshi R Dogra S Mendiratta DK Narang P Kalantri S Reingold AL Colford JM Riley LW Menzies D 《American journal of respiratory and critical care medicine》2006,174(3):349-355
RATIONALE: Although interferon-gamma (IFN-gamma) assays are promising alternatives to the tuberculin skin test (TST), their serial testing performance is unknown. OBJECTIVE: To compare TST and IFN-gamma conversions and reversions in healthcare workers. METHODS: We prospectively followed-up 216 medical and nursing students in India who underwent baseline and repeat testing (after 18 mo) with TST and QuantiFERON-TB Gold In-Tube (QFT). TST conversions were defined as reactions greater than or equal to 10 mm, with increments of 6 or 10 mm over baseline. QFT conversions were defined as baseline IFN-gamma less than 0.35 and follow-up IFN-gamma greater than or equal to 0.35 or 0.70 IU/ml. QFT reversions were defined as baseline IFN-gamma greater than or equal to 0.35 and follow-up IFN-gamma less than 0.35 IU/ml. RESULTS: Of the 216 participants, 48 (22%) were TST-positive, and 38 (18%) were QFT-positive at baseline. Among 147 participants with concordant baseline negative results, TST conversions occurred in 14 (9.5%; 95% confidence interval [CI] = 5.3-15.5) using the 6 mm increment definition, and 6 (4.1%; 95% CI = 1.5-8.7) using the 10 mm increment definition. QFT conversions occurred in 17/147 participants (11.6%; 95% CI = 6.9-17.9) using the definition of IFN-gamma greater than or equal to 0.35 IU/ml, and 11/147 participants (7.5%; 95% CI = 3.8-13.0) using IFN-gamma greater than or equal to 0.70 IU/ml. Agreement between TST (10 mm increment) and QFT conversions (>or= 0.70 IU/ml) was 96% (kappa = 0.70). QFT reversions occurred in 2/28 participants (7%) with baseline concordant positive results, as compared with 7/10 participants (70%) with baseline discordant results (p < 0.001). CONCLUSIONS: IFN-gamma assay shows promise for serial testing, but repeat results need to be interpreted carefully. To meaningfully interpret serial results, the optimal thresholds to distinguish new infections from nonspecific variations must be determined. 相似文献
88.
Charlotte Pawlyn David A. Cairns Tom Menzies John R. Jones Matthew W. Jenner Gordon Cook Kevin D. Boyd Mark T. Drayson Martin F. Kaiser Roger G. Owen Walter Gregory Gareth J. Morgan Graham H. Jackson Faith E. Davies 《Haematologica》2022,107(1):231
Autologous stem cell transplant (ASCT) remains the standard of care for consolidation after induction therapy for eligible patients with newly diagnosed myeloma. In recent clinical trials comparing ASCT to delayed ASCT, patients aged over 65 were excluded. In real-world practice stem cell transplants are not restricted to those aged under 65 and clinicians decide on transplant eligibility based on a patient’s fitness rather than a strict age cut-off. Data from the UK NCRI Myeloma XI trial, a large phase III randomized controlled trial with pathways for transplant-eligible and -ineligible patients, were used in an exploratory analysis to examine the efficacy and toxicity of ASCT in older patients including an analysis using an age-matched population to compare outcomes for patients receiving similar induction therapy with or without ASCT. Older patients within the transplant-eligible pathway were less likely to undergo stem cell harvest at the end of induction than younger patients and of those patients undergoing ASCT there was a reduction in progression-free survival associated with increasing age. ASCT in older patients was well tolerated with no difference in morbidity or mortality between patients aged <65, 65-69 and 70-75 years. In an age-matched population of patients including those in both the transplant- eligible and -ineligible pathways there was a significant advantage associated with undergoing ASCT with increases in progression-free survival (hazard ratio 0.41, P<0.0001) and overall survival (hazard ratio 0.51, P<0.0001), which persisted even after adjustment for baseline covariates including those related to frailty and response to induction. These findings support the use of ASCT for selected fit, older myeloma patients. EudraCT number, 2009-010956-93 相似文献
89.
张宗德 《结核与肺部疾病杂志》2007,2(1):17-29
目的:结核菌素皮肤试验(TST)是发现潜伏性结核感染(LTBI)的经典方法,目前γ干扰素试验(IGRA)也是可供选择的技术.我们比较了不同人群、不同临床状态下TST及IGRA的成本效益.方法:20年来加拿大对入境的外国移民或结核病接触者采用了不同的筛查策略,我们采用Markov模式比较了预期发现的病例数与成本的分析.并对比较便宜的商品试剂盒IGRA:γ干扰素定量测定(QFT)进行了调查.模型(model)输入数据均源于已发表的文献.结果:对入境移民,采用胸部X线拍片(CXR)是符合成本-效益原则的,而QFT是最不符合成本-效益原则者.序贯进行TST及QFT比任何情况下单一行QFT更符合成本-效益.在特定的(选择的)亚群中,也比单一进行TST更符合成本-效益原则.在密切接触者及不定期接触者中,采用TST或QFT筛查是节约成本的(cost saving):除在婴儿期后接种BCG的接触者外,采用TST的收益(savings)大于QFT.结论:只有在结核病高危人群中,以TST或QFT筛查LTBI是符合成本-效益的.TST阳性者再行QFT是最符合成本-效益原则的. 相似文献
90.
E G Teixeira D Menzies G W Comstock A J L A Cunha A L Kritski L C Soares E Bethlem G Zanetti A Ruffino-Netto M T C T Belo L Selig M M Castello Branco D Cherri S Maia R Marandino R R Luiz R E Chaisson A Trajman 《The international journal of tuberculosis and lung disease》2005,9(8):841-847
SETTING: Five medical schools in three cities with different tuberculosis (TB) incidence rates in Rio de Janeiro State, Brazil. OBJECTIVE: To estimate prevalence of and associated factors for latent tuberculosis infection (LTBI) among medical students. DESIGN: A cross-sectional survey was conducted among undergraduate students in pre-clinical, early and late clinical years from schools in cities with low (28/100,000), intermediate (63/100,000) and high (114/100,000) TB incidence rates. Information on socio-demographic profile, previous BCG vaccination, potential TB exposure, co-morbidity and use of respiratory protective masks was obtained. A tuberculin skin test (TST) was performed using the Mantoux technique by an experienced professional. A positive TST, defined as induration > or = 10 mm, was considered LTBI. RESULTS: LTBI prevalence was 6.9% (95%CI 5.4-8.6). In multivariate analysis, male sex (adjusted odds ratio [aOR] 1.8; 95% CI 1.1-3.0), late clinical years (aOR 1.9; 95% CI 1.01-3.5), intermediate TB incidence (aOR 4.3; 95% CI 1.3-14.6) and high TB incidence in the city of medical school (aOR 5.1; 95% CI 1.6-16.8) were significantly associated with LTBI. CONCLUSIONS: The higher prevalence of LTBI in late clinical years suggests that medical students are at increased risk for nosocomial Mycobacterium tuberculosis infection. The implementation of a TB control program may be necessary in medical schools, particularly in cities with higher TB incidence. 相似文献