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91.

Background

DNA methylation markers could serve as useful biomarkers, both as markers for progression and for urine-based diagnostic assays.

Objective

Identify bladder cancer (BCa)–specific methylated DNA sequences for predicting pTa-specific progression and detecting BCa in voided urine.

Design, setting, and participants

Genome-wide methylation analysis was performed on 44 bladder tumours using the Agilent 244K Human CpG Island Microarray (Agilent Technologies, Santa Clara, CA, USA). Validation was done using a custom Illumina 384-plex assay (Illumina, San Diego, CA, USA) in a retrospective group of 77 independent tumours. Markers for progression were identified in pTa (n = 24) tumours and validated retrospectively in an independent series of 41 pTa tumours by the SNaPshot method (Applied Biosystems, Foster City, CA, USA).

Measurements

The percentage of methylation in tumour and urine samples was used to identify markers for detection and related to the end point of progression to muscle-invasive disease with Kaplan-Meier models and multivariate analysis.

Results and limitations

In the validation set, methylation of the T-box 2 (TBX2), T-box 3 (TBX3), GATA binding protein 2 (GATA2), and Zic family member 4 (ZIC4) genes was associated with progression to muscle-invasive disease in pTa tumours (p = 0.003). Methylation of TBX2 alone showed a sensitivity of 100%, a specificity of 80%, a positive predictive value of 78%, and a negative predictive value of 100%, with an area under the curve of 0.96 (p < 0.0001) for predicting progression. Multivariate analysis showed that methylation of TBX3 and GATA2 are independent predictors of progression when compared to clinicopathologic variables (p = 0.04 and p = 0.03, respectively). The predictive accuracy improved by 23% by adding methylation of TBX2, TBX3, and GATA2 to the European Organisation for Research and Treatment of Cancer risk scores. We further identified and validated 110 CpG islands (CGIs) that are differentially methylated between tumour cells and control urine. The limitation of this study is the small number of patients analysed for testing and validating the prognostic markers.

Conclusions

We have identified four methylation markers that predict progression in pTa tumours, thereby allowing stratification of patients for personalised follow-up. In addition, we identified CGIs that will enable detection of bladder tumours in voided urine.  相似文献   
92.
According to global neuronal workspace (GNW) theory, conscious access relies on long-distance cerebral connectivity to allow a global neuronal ignition coding for conscious content. In patients with schizophrenia and bipolar disorder, both alterations in cerebral connectivity and an increased threshold for conscious perception have been reported. The implications of abnormal structural connectivity for disrupted conscious access and the relationship between these two deficits and psychopathology remain unclear. The aim of this study was to determine the extent to which structural connectivity is correlated with consciousness threshold, particularly in psychosis. We used a visual masking paradigm to measure consciousness threshold, and diffusion MRI tractography to assess structural connectivity in 97 humans of either sex with varying degrees of psychosis: healthy control subjects (n = 46), schizophrenia patients (n = 25), and bipolar disorder patients with (n = 17) and without (n = 9) a history of psychosis. Patients with psychosis (schizophrenia and bipolar disorder with psychotic features) had an elevated masking threshold compared with control subjects and bipolar disorder patients without psychotic features. Masking threshold correlated negatively with the mean general fractional anisotropy of white matter tracts exclusively within the GNW network (inferior frontal-occipital fasciculus, cingulum, and corpus callosum). Mediation analysis demonstrated that alterations in long-distance connectivity were associated with an increased masking threshold, which in turn was linked to psychotic symptoms. Our findings support the hypothesis that long-distance structural connectivity within the GNW plays a crucial role in conscious access, and that conscious access may mediate the association between impaired structural connectivity and psychosis.  相似文献   
93.
Aims. To delineate common epilepsy features associated with the presence of glutamic acid decarboxylase autoantibodies (GAD65‐Ab). Methods. Three consecutive cases of GAD65‐Ab encephalitis patients, followed in our neurological department, were investigated with regards to clinical semiology and EEG. Results. These patients presented new‐onset subtle ictal clinical features. Patients 1 and 2 described prolonged and transitory feelings of “déjà vudéjà vécu” and a “dreamy state”. Patient 3 was admitted for subsequent transient aphasia events followed by paroxysmal behavioural disturbances. Epileptic origin of the symptoms was confirmed using either a standard EEG (observation of temporal status epilepticus in one case) or a prolonged EEG (focal epileptiform activity during an asymptomatic period for two patients). All patients suffered from clinical focal status epilepticus. Patients 1 and 2 presented with temporo‐mesial seizures in agreement with the definition for limbic encephalitis, whereas Patient 3 presented with neocortical (lateral temporal and frontal lobe) seizures arguing for a non‐limbic encephalitis. A high level of GAD65‐Ab was found in cerebral spinal fluid, confirming a diagnosis of epilepsy associated with GAD65‐Ab encephalitis. Conclusion. Encephalitis seems to be a frequent neurological syndrome associated with GAD65‐Ab disorders. Epilepsy may be more frequent and severe than currently suggested, as ictal semiology may be subtle for these outpatients in whom standard EEG is commonly falsely reassuring. Subtle focal status epilepticus is a particular semiology of the GAD65‐Ab encephalitis spectrum.  相似文献   
94.
During status epilepticus (SE), synaptic γ‐aminobutyric acid A receptors (GABAARs) become internalized and inactive, whereas spare N‐methyl‐d ‐aspartate receptors (NMDARs) assemble, move to the membrane, and become synaptically active. When treatment of SE is delayed, the number of synaptic GABAARs is drastically reduced, and a GABAA agonist cannot fully restore inhibition. We used a combination of low‐dose diazepam (to stimulate the remaining GABAARs), ketamine (to mitigate the effect of the NMDAR increase), and valproate (to enhance inhibition at a nonbenzodiazepine site) to treat seizures in a model of severe cholinergic SE. High doses of diazepam failed to stop electrographic SE, showing that benzodiazepine pharmacoresistance had developed. The diazepam‐ketamine‐valproate combination was far more effective in stopping SE than triple‐dose monotherapy using the same individual drugs. Isobolograms showed that this drug combination's therapeutic actions were synergistic, with positive cooperativity between drugs, whereas drug toxicity was simply additive, without positive or negative cooperativity. As a result, the therapeutic index was improved by this drug combination compared to monotherapy. These results suggest that synergistic drug combinations that target receptor changes can control benzodiazepine‐refractory SE.  相似文献   
95.
This paper provides up to date prevalence estimates of mental disorders in Germany derived from a national survey (German Health Interview and Examination Survey for Adults, Mental Health Module [DEGS1‐MH]). A nationally representative sample (N = 5318) of the adult (18–79) population was examined by clinically trained interviewers with a modified version of the Composite International Diagnostic Interview (DEGS‐CIDI) to assess symptoms, syndromes and diagnoses according to DSM‐IV‐TR (25 diagnoses covered). Of the participants 27.7% met criteria for at least one mental disorder during the past 12 months, among them 44% with more than one disorder and 22% with three or more diagnoses. Most frequent were anxiety (15.3%), mood (9.3%) and substance use disorders (5.7%). Overall rates for mental disorders were substantially higher in women (33% versus 22% in men), younger age group (18–34: 37% versus 20% in age group 65–79), when living without a partner (37% versus 26% with partnership) or with low (38%) versus high socio‐economic status (22%). High degree of urbanization (> 500,000 inhabitants versus < 20,000) was associated with elevated rates of psychotic (5.2% versus 2.5%) and mood disorders (13.9% versus 7.8%). The findings confirm that almost one third of the general population is affected by mental disorders and inform about subsets in the population who are particularly affected. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
96.

Objective

to describe the incidence and characteristics of patient safety incidents in midwifery-led care for low-risk pregnant women.

Design

multi-method study.

Setting

20 midwifery practices in the Netherlands; 1,000 patient records.

Population

low-risk pregnant women.

Methods

prospective incident reporting by midwives during 2 weeks; questionnaire on safety culture and retrospective content analysis of 1,000 patient records in 2009.

Main outcome measures

incidence, type, impact and causes of safety incidents.

Results

in the 1,000 patient records involving 14,888 contacts, 86 safety incidents were found with 25 of these having a noticeable effect on the patient. Low-risk pregnant women in midwifery care had a probability of 8.6% for a safety incident (95% CI 4.8–14.4). In 9 safety incidents, temporary monitoring of the mother and/or child was necessary. In another 6 safety incidents, reviewers reported psychological distress for the patient. Hospital admission followed from 1 incident. No safety incidents were associated with mortality or permanent harm. The majority of incidents found in the patient records concerned treatment and organisational factors.

Conclusions

a low prevalence of patient safety incidents was found in midwifery care for low-risk pregnant women. This first systematic study of patient safety in midwifery adds to the base of evidence regarding the safety of midwifery-led care for low-risk women. Nevertheless, some areas for improvement were found. Improvement of patient safety should address the better adherence to practice guidelines for patient risk assessment, better implementation of interventions for known lifestyle risk factors and better availability of midwives during birthing care.  相似文献   
97.
Human mesenchymal stem cells (MSCs) are promising candidates for therapeutic applications such as tissue engineering. However, one of the main challenges is to improve oxygen supply to hypoxic areas to reduce oxygen gradient formation while preserving MSC differentiation potential and viability. For this purpose, a marine hemoglobin, HEMOXCell, was evaluated as an oxygen carrier for culturing human bone marrow MSCs in vitro for future three‐dimensional culture applications. Impact of HEMOXCell on cell growth and viability was assessed in human platelet lysate (hPL)‐supplemented media. Maintenance of MSC features, such as multipotency and expression of MSC specific markers, was further investigated by biochemical assays and flow cytometry analysis. Our experimental results highlight its oxygenator potential and indicate that an optimal concentration of 0.025 g/L HEMOXCell induces a 25%‐increase of the cell growth rate, preserves MSC phenotype, and maintains MSC differentiation properties; a two‐fold higher concentration induces cell detachment without altering cell viability. Our data suggest the potential interest of HEMOXCell as a natural oxygen carrier for tissue engineering applications to oxygenate hypoxic areas and to maintain cell viability, functions and “stemness.” These features will be further tested within three‐dimensional scaffolds.  相似文献   
98.
99.
IntroductionThe World Health Organization recommends full disclosure of HIV‐positive status to adolescents who acquired HIV perinatally (APHIV) by age 12. However, even among adolescents (aged 10–19) already on antiretroviral therapy (ART), disclosure rates are low. Caregivers often report the child being too young and fear of disclosure worsening adolescents’ mental health as reasons for non‐disclosure. We aimed to identify the predictors of disclosure and the association of disclosure with adherence, viral suppression and mental health outcomes among adolescents in sub‐Saharan Africa.MethodsAnalyses included three rounds (2014–2018) of data collected among a closed cohort of adolescents living with HIV in Eastern Cape, South Africa. We used logistic regression with respondent random‐effects to identify factors associated with disclosure, and assess differences in ART adherence, viral suppression and mental health symptoms between adolescents by disclosure status. We also explored differences in the change in mental health symptoms and adherence between study rounds and disclosure groups with logistic regression.ResultsEight hundred and thirteen APHIV were interviewed at baseline, of whom 769 (94.6%) and 729 (89.7%) were interviewed at the second and third rounds, respectively. The proportion aware of their HIV‐positive status increased from 63.1% at the first round to 85.5% by the third round. Older age (adjusted odds ratio [aOR]: 1.27; 1.08–1.48) and living in an urban location (aOR: 2.85; 1.72–4.73) were associated with disclosure between interviews. There was no association between awareness of HIV‐positive status and ART adherence, viral suppression or mental health symptoms among all APHIV interviewed. However, among APHIV not aware of their status at baseline, adherence decreased at the second round among those who were disclosed to (N = 131) and increased among those not disclosed to (N = 151) (interaction aOR: 0.39; 0.19–0.80). There was no significant difference in the change in mental health symptoms between study rounds and disclosure groups.ConclusionsAwareness of HIV‐positive status was not associated with higher rates of mental health symptoms, or lower rates of viral suppression among adolescents. Disclosure was not associated with worse mental health. These findings support the recommendation for timely disclosure to APHIV; however, adherence support post‐disclosure is important.  相似文献   
100.
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