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Estrogens, whether natural or synthetic, clearly influence reproductive development, senescence, and carcinogenesis. Pyrethroid insecticides are now the most widely used agents for indoor pest control, providing potential for human exposure. Using the MCF-7 human breast carcinoma cell line, we studied the estrogenic potential of several synthetic pyrethroid compounds in vitro using pS2 mRNA levels as the end point. We tested sumithrin, fenvalerate, d-trans allethrin, and permethrin. Nanomolar concentrations of either sumithrin or fenvalerate were sufficient to increase pS2 expression slightly above basal levels. At micromolar concentrations, these two pyrethroid compounds induced pS2 expression to levels comparable to those elicited by 10 nM 17ss-estradiol (fivefold). The estrogenic activity of sumithrin was abolished with co-treatment with an antiestrogen (ICI 164,384), whereas estrogenic activity of fenvalerate was not significantly diminished with antiestrogen co-treatment. In addition, both sumithrin and fenvalerate were able to induce cell proliferation of MCF-7 cells in a dose-response fashion. Neither permethrin nor d-trans allethrin affected pS2 expression. Permethrin had a noticeable effect on cell proliferation at 100 microM, whereas d-trans allethrin slightly induced MCF-7 cell proliferation at 10 microM, but was toxic at higher concentrations. Overall, our studies imply that each pyrethroid compound is unique in its ability to influence several cellular pathways. These findings suggest that pyrethroids should be considered to be hormone disruptors, and their potential to affect endocrine function in humans and wildlife should be investigated.  相似文献   
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ObjectivesDecellularization aims to harness the regenerative properties of native extracellular matrix. The objective of this study was to evaluate different methods of decellularization of periodontal ligament cell sheets whilst maintaining their structural and biological integrity.DesignHuman periodontal ligament cell sheets were placed onto melt electrospun polycaprolactone (PCL) membranes that reinforced the cell sheets during the various decellularization protocols. These cell sheet constructs (CSCs) were decellularized under static/perfusion conditions using a) 20 mM ammonium hydroxide (NH4OH)/Triton X-100, 0.5% v/v; and b) sodium dodecyl sulfate (SDS, 0.2% v/v), both +/− DNase besides Freeze–thaw (F/T) cycling method. CSCs were assessed using a collagen quantification assay, immunostaining and scanning electron microscopy. Residual fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were assessed with Bio-plex assays.ResultsDNA removal without DNase was higher under static conditions. However, after DNase treatment, there were no differences between the different decellularization methods with virtually 100% DNA removal. DNA elimination in F/T was less efficient even after DNase treatment. Collagen content was preserved with all techniques, except with SDS treatment. Structural integrity was preserved after NH4OH/Triton X-100 and F/T treatment, while SDS altered the extracellular matrix structure. Growth factor amounts were reduced after decellularization with all methods, with the greatest reduction (to virtually undetectable amounts) following SDS treatment, while NH4OH/Triton X-100 and DNase treatment resulted in approximately 10% retention.ConclusionsThis study showed that treatment with NH4OH/Triton X-100 and DNase solution was the most efficient method for DNA removal and the preservation of extracellular matrix integrity and growth factors retention.  相似文献   
4.
Deficits in the capacity to engage in social interactions are a core deficit associated with Autistic Disorder (AD) and Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS). These deficits emerge at a young age, making screening for social interaction deficits and interventions targeted at improving capacity in this area important for early identification and intervention. Screening and early intervention efforts are particularly important given the poor short and long term outcomes for children with Autism Spectrum Disorders (ASDs) who experience social interaction deficits. The Screen for Social Interaction (SSI) is a well-validated screening measure that examines a child's capacity for social interaction using a developmental approach. The present study identified four underlying factors measured by the SSI, namely, Connection with Caregiver, Interaction/Imagination, Social Approach/Interest, and Agreeable Nature. The resulting factors were utilized to compare social interaction profiles across groups of children with AD, PDD-NOS, children with non-ASD developmental and/or psychiatric conditions and typically developing children. The results indicate that children with AD and those with PDD-NOS had similar social interaction profiles, but were able to be distinguished from typically developing children on every factor and were able to be distinguished from children with non-ASD psychiatric conditions on every factor except the Connection with Caregiver factor. In addition, children with non-ASD developmental and/or psychiatric conditions could be distinguished from typically developing children on the Connection with Caregiver factor and the Social Approach/Interest factor. These findings have implications for screening and intervention for children with ASDs and non-ASD psychiatric conditions.  相似文献   
5.
BackgroundExercising, including dancing, has been recommended to improve cardiovascular health of older people. Herein, we conducted a systematic review and meta-analysis verifying the effects of dance interventions on cardiovascular risk (CVR) in the elderly, comparing dancers to non-exercise controls and other types of exercise, in randomised (RCTs) and non-randomised control trials (nRCTs). Primary/Secondary outcomes: peak oxygen consumption (VO2peak)/anthropometric measurements (body weight, BMI), and lipid profile.MethodsData Sources: MEDLINE, Cochrane Wiley, Clinical Trials.gov, PEDRO and LILACS databases. Study Selection: RCTs and nRCTs comparing elderly before and after dance interventions with non-exercising controls and/or practitioners of other types of exercise. Two independent reviewers extracted data and assessed the quality of included studies.ResultsA total of 937 articles were retrieved, 64 full texts were assessed for eligibility, and 7 articles met the inclusion criteria. Pooled mean differences between intervention and control were calculated by random-effects model. VO2peak improved in favour of dancers (3.4 mL kg−1 min−1, 95%CI: 1.08, 5.78, I2 = 71%), compared to non-exercise controls. No differences were found between dance and other exercises. Body weight and BMI were not altered by dance interventions.ConclusionsDance interventions may increase VO2peak compared to non-exercising controls. Results also indicate it is as effective as other types of exercise in improving aerobic capacity of the elderly. Dancing might be a potential exercise intervention for improving cardiorespiratory fitness and consequent CVR associated with ageing. Proper reporting on adverse events is needed to base the benefits of dancing for the older on both efficacy and safety of the interventions.  相似文献   
6.
ObjectivesFalls are an important issue in older adults as they are frequent, deleterious, and often lead to repeated consultations at the emergency department (ED) and unplanned hospitalizations. Our principal objective was to provide an inventory of interventions designed to prevent unplanned readmissions or ED visits of older patients presenting to hospital with a fall.DesignSystematic review performed on February 11, 2019 in MEDLINE via PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science, without date or language restriction. We manually updated this search in August 1, 2019. Study selection, data extraction and risk of bias assessment were conducted independently by 2 reviewers.Setting and ParticipantsWe included studies reporting interventions to prevent unplanned readmissions or ED visits of older patients (aged 65 years or over) presenting to hospital because of a fall.ResultsWe identified 475 unique citations after removing duplicates and included 6 studies (2 observational and 4 interventional studies). The studies were published between 2012 and 2019; they evaluated heterogeneous interventions that were frequently multifaceted and multidisciplinary. The interventions were shown effective in reducing readmissions or ED revisits compared with control groups in 3 studies (relative risk reductions between 30% and 65%), all of which were multifaceted and 2/3 multidisciplinary.Conclusions and ImplicationsWith 6 articles showing inconsistent results, our study highlights the need to adequately design and evaluate interventions to reduce the burden of hospital readmissions among older fallers. Retrieved studies are recent, which underlines that hospital readmissions are a current concern for researchers and public health authorities [PROSPERO registration number: CRD42019131965].  相似文献   
7.
目的探讨慢性不可预见性应激(chronic unpredictable stress,CUS)对大鼠神经递质和下丘脑-垂体-肾上腺皮质轴(hypothalamic-pituitary-adrenal axis,HPA)的影响。方法 16只SD雄性大鼠随机数字表法分为正常对照组和模型组。模型组大鼠给予慢性不可预见性的应激,检测其体质量增长量;通过蔗糖偏嗜实验观察大鼠行为学的改变;采用高效液相-电化学法测定海马多巴胺(dopamine,DA)、5-羟色胺(5-hydroxytryptamine,5-HT),高效液相-荧光法测定谷氨酸(glutamic acid,Glu)、γ-氨基丁酸(γ-aminobutyric acid,γ-GABA);用放射免疫法检测血浆及下丘脑促肾上腺皮质激素释放激素(corticotropin-releasing hormone,CRH)、促肾上腺皮质激素(adrenocorticotropic hormone,ACTH)、皮质酮(corticosterone,CORT)。结果与正常对照组相比,模型组大鼠体质量增长量显著降低,糖水消耗量明显下降,DA、γ-GABA显著降低,5-HT、Glu有升高的趋势,ACTH显著降低,CORT质量浓度明显增高。结论 CUS会导致大鼠行为学的改变,HPA轴的紊乱。  相似文献   
8.
The objective of this study was to develop a questionnaire to assess child-to-parent aggression in adolescents and to document the extent of the problem. The questionnaire developed in this study, the Child-to-Parent Aggression Questionnaire (CPAQ), includes forms of physical and psychological aggression directed at both the mother and the father. It also includes open questions about the reasons for the aggressive acts. The CPAQ was completed by a sample of 2719 adolescents (age range: 13–18 years old, 51.4% girls). Confirmatory factor analysis supported a four-factor correlated structure (physical aggression against mother, physical aggression against father, psychological aggression against mother, and psychological aggression against father). Psychological and physical aggression against the mother was more frequent than against the father. However, there were no differences with regard to severe forms of aggression. Girls scored significantly higher on all indicators of psychological aggression, including severe psychological aggression. Nevertheless, except for the prevalence of physical aggression against mothers, which was higher in females, there were no significant differences in physical aggression against parents. Finally, the reasons provided by the adolescents for the aggression included both instrumental (e.g., to obtain permission to get home late and to access their computers) and reactive reasons (e.g., anger and self-defense). These findings highlight the complexity of child-to-parent aggression in adolescence.  相似文献   
9.
The current study is the first to examine the association between chronic loneliness and perceived health, school absence due to illness, sleep duration and disturbance, in a sample of pre-adolescents (N = 209). Loneliness was measured in three collection waves that were 18 months apart and covered the ages 8–11 years. Using growth mixture modeling, two groups were identified with discrete growth patterns of loneliness: (a) relatively high, reducing loneliness (48%), and (b) low, stable loneliness (52%). At age 11 years, those in the relatively high, reducing lonely group reported higher levels of depressive symptoms, poorer general health, took longer to get to sleep, and had greater sleep disturbance than children in the low, stable loneliness group. These findings suggest that there may be long-term health effects of experiencing high loneliness in middle childhood, even when loneliness levels reduce to normal levels at pre-adolescence.  相似文献   
10.
Study objectivePrevious randomized controlled trials (RCTs) suggest that auricular stimulation (AS) is safe and effective in treatment of preoperative anxiety; however, a systematic evaluation is lacking. The aim was to summarize the evidence on efficacy and safety of AS for preoperative anxiety, as well as for other outcomes.DesignWe conducted a systematic review of RCTs including patients from all available populations. The search was done through MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science and Scopus Database from inception to June 2020. Study selection and data extraction were performed in by 2 independent reviewers with ability to resolve disagreements by a third author. Meta-analyses as well as the risk of bias and evidence quality assessments were performed according to the Cochrane 6.2, 2021 handbook recommendations.InterventionsWe compared AS with pharmacological and non-pharmacological interventions for different outcomes.MeasurementsWe assessed the repercussion of the evaluated interventions over anxiety scores and their safety, physiological parameters, perioperative medications requirement and intensity of postoperative pain.Main resultsWe have included 15 studies with 1603 patients. AS has presented reduced anxiety scores as compared to the sham control (Standardized Mean Difference (SMD) -0.72, 95% confidence interval (CI) -1.09 to −0.36, p < 0.0001; 8 trials; 701 patients; heterogeneity: I2 80%; GRADE: moderate certainty) and to no intervention (SMD -1.01, 95% CI -1.58 to −0.45, p = 0.0004; 4 trials; 420 patients; heterogeneity: I2 84%; GRADE: very low certainty). There was no difference between AS and benzodiazepines (SMD -0.03; 95% CI: −0.34 to 0.28; p = 0.84; 3 trials; 158 patients; heterogeneity: I2 0%; GRADE: very low certainty). No trials reported serious adverse effects of AS.ConclusionsAS may be useful in treatment of preoperative anxiety. Due to heterogenous certainty in effect estimates, further research is needed to clarify the actual efficacy of AS for preoperative anxiety.  相似文献   
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