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Objectives
To compare soleus spinal reflex excitability, presynaptic inhibition and recurrent inhibition between chronic ankle instability (CAI), acute Lateral Ankle Sprain coper (LAS-coper) and healthy populations. The relationship between spinal reflex excitability and pain and perceived instability in people with CAI was also examined.Design
Cross-sectional laboratory experiment.Methods
Twelve individuals with CAI, twelve ‘copers’ and twelve healthy age, limb and gender-matched controls participated. Soleus H-reflex recruitment curves, pre-synaptic excitability and recurrent inhibition of the spinal-reflex pathway were examined during static double- and single-leg stance. Reporting of pain and perceived instability were used to perform a regression analysis on measures of soleus spinal excitability in people with CAI, LAS-coper and healthy controls.Results
Soleus spinal reflex excitability was greater during single-leg stance in CAI compared to healthy and coper individuals (p = <0.001). Pre-synaptic inhibition was three-times less in CAI participants compared to both healthy controls and copers (p = <0.001). There were no differences between healthy and coper participants in spinal-level measures of sensorimotor control. Reports of pain explained 15–16% of the variance in soleus spinal reflex excitability and presynaptic inhibition during single and double-leg stance, while perceived instability explained 20% of the variance in spinal reflex during single leg stance only.Conclusions
CAI participants presented with an inability to suppress soleus spinal reflexes during tasks with increased postural threat; likely due to disinhibition of pre-synaptic mechanisms. Pain and perceived instability may contribute to changes in spinal-level sensorimotor control in CAI. 相似文献Objectives
Resistance training (RT) is emerging as a training modality to improve motor function and facilitate physical activity participation in children across the motor proficiency spectrum. Although RT competency assessments have been established and validated among adolescent cohorts, the extent to which these methods are suitable for assessing children’s RT skills is unknown. This project aimed to assess the psychometric properties of the adapted Resistance Training Skills Battery for Children (RTSBc), in children with varying motor proficiency.Design
Repeated measures design with 40 participants (M age = 8.2 ± 1.7 years) displaying varying levels of motor proficiency.Methods
Participants performed the adapted RTSBc on two occasions, receiving a score for their execution of each component, in addition to an overall RT skill quotient child (RTSQc). Cronbach’s alpha, intra-class correlation (ICC), Bland–Altman analysis, and typical error were used to assess test–retest reliability. To examine construct validity, exploratory factor analysis was performed alongside computing correlations between participants’ muscle strength, motor proficiency, age, lean muscle mass, and RTSQc.Results
The RTSBc displayed an acceptable level of internal consistency (alpha = 0.86) and test–retest reliability (ICC range = 0.86–0.99). Exploratory factor analysis supported internal test structure, with all six RT skills loading strongly on a single factor (range 0.56–0.89). Analyses of structural validity revealed positive correlations for RTSQc in relation to motor proficiency (r = 0.52, p < 0.001) and strength scores (r = 0.61, p < 0.001).Conclusions
Analyses revealed support for the construct validity and test–retest reliability of the RTSBc, providing preliminary evidence that the RTSBc is appropriate for use in the assessment of children’s RT competency. 相似文献Objectives
Pre-eclampsia is a placental, inflammatory disease modified by maternal anti-oxidant status to give a syndrome. In its most severe forms pre-eclampsia is followed by maternal and neonatal mortality and morbidity. Bilirubin is a known antioxidant and as such is associated with a reduced risk of cardiovascular and respiratory disease. Hence we aimed to find an association between maternal bilirubin levels and the clinical severity of the disease.Study design
A retrospective observational study of 50,712 pregnancies, 925 of which had pre-eclampsia (1999–2010), to examine the association between bilirubin level and perinatal outcome.Results
In women with pre-eclampsia, those with bilirubin levels in the lowest quintile were more likely to require caesarean section (p = 0.001, aOR 2.59 (1.52–5.72)). The lowest quintile of bilirubin levels is associated with an increased risk of poor maternal (p = 0.002, aOR 3.52 (95%CI 1.6–7.7)) and infant/fetal (p = 0.001, OR = 3.05 (95%CI = 1.63–5.72)) outcome.Conclusions
Low levels of bilirubin were associated with poor maternal and infant outcomes in women diagnosed with pre-eclampsia. Bilirubin may act as an anti-oxidant in this condition and thus modify the disease. 相似文献A core component of treatment provided by early intervention for psychosis (EI) services is ensuring individuals remain successfully engaged with the service. This ensures they can receive the care they may need at this critical early stage of illness. Unfortunately, rates of disengagement are high in individuals with a first episode of psychosis (FEP), representing a major barrier to effective treatment. This study aimed to ascertain the rates and determinants of disengagement and subsequent re-engagement of young people with FEP in a well-established EI service in Melbourne, Australia.
MethodThis cohort study involved all young people, aged 15–24, who presented to the Early Psychosis Prevention and Intervention Centre (EPPIC) service with FEP between 1st January 2011 and 1st September 2014. Data were collected retrospectively from clinical files and electronic records. Cox regression analysis was used to identify determinants of disengagement and re-engagement.
ResultsA total of 707 young people presented with FEP during the study period, of which complete data were available for 700. Over half of the cohort (56.3%, N = 394) disengaged at least once during their treatment period, however, the majority of these individuals (85.5%, N = 337) subsequently re-engaged following the initial episode of disengagement. Of those who disengaged from the service, 54 never re-engaged, representing 7.6% of the total cohort. Not being in employment, education or training, not having a family history of psychosis in second degree relatives and using cannabis were found to be significant predictors of disengagement. No significant predictors of re-engagement were identified.
ConclusionIn this study, the rate of disengagement in young people with first-episode psychosis was higher than found previously. Encouragingly, rates of re-engagement were also high. The concept of disengagement from services might be more complex than previously thought with individuals disengaging and re-engaging a number of times during their episode of care. What prompts individuals to re-engage with services needs to be better understood.
相似文献