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61.

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   
62.

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   
63.
BackgroundMonitoring of white cell counts during clozapine treatment leads to cessation of therapy if levels fall below pre-determined values. Reductions in white cell counts, driven by lower levels of lymphocytes, have been observed with coronavirus disease 2019 (COVID-19). Neutropenia during COVID-19 has not been reported. We present data for 56 patients who were taking clozapine and had COVID-19.MethodsWe included patients who were taking clozapine at the time they tested positive for COVID-19. We compared absolute neutrophil counts, lymphocyte counts and white cell counts between baseline and the first week of infection, and baseline and the second week of infection.ResultsWe observed reductions in absolute neutrophil counts (p = 0.005), lymphocyte counts (p = 0.003) and white cell counts (p < 0.001) between baseline and the first 7 days of COVID-19. All cell counts had returned to baseline levels by days 8 to 14. Six patients experienced neutropenia (absolute neutrophil counts < 2.0 × 109/L) and of those, 4 underwent mandatory cessation of clozapine. For 3 patients, clozapine treatment had been established for more than 6 months with no previous neutropenia, neutrophil levels returned to baseline within 2 weeks and no further neutropenia was observed on restarting treatment.LimitationsThis was a retrospective chart review; larger cohorts are required. Clozapine plasma levels were largely not measured by clinicians.ConclusionThese data strongly suggest that mild neutropenia in the acute phase of COVID-19 in patients who are well established on clozapine is more likely to be a consequence of the virus than of clozapine treatment.  相似文献   
64.
We have previously shown that kainic acid (KA) increases nitric oxide (NO) synthase (NOS) production in the rat dentate gyrus (DG) and hippocampus (CA3), and NOS inhibition [(by NG-nitro-L-arginine methylester (L-NAME)] modulates the vasoactive intestinal peptide (VIP)-responsive gene, activity-dependent neuroprotective protein, and alters neuro- and astrogliogenesis (Cosgrave et al. in Neurobiol Dis 30(3):281–292 2008, J Mol Neurosci 39(1–2):9–21, 2009, 2010). In the present study, using the same model we demonstrate that VIP synthesis is differentially regulated by the NO-cyclic guanosine monophosphate (cGMP) pathway in the DG and CA3 at 3 h and 3 days post-KA. At 3 h post-KA: In L-NAME+KA/7-nitroindazole (7-NI)+KA, stratum granulosum (SG) and subgranular zone (SGZ) cells were intensely stained for VIP when compared with L-NAME/7-NI/KA alone. Soluble guanylyl cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, blocks cGMP production), suppressed astrocytic activation (glial fibrillary acidic protein) but other cell types were VIP+; however, ODQ+KA suppressed overall VIP synthesis in the DG. At 3 days post-KA: In L-NAME+KA/7-NI+KA, SGZ and SG cells continued to express VIP, while in the KA alone, only SGZ cells were VIP+. ODQ increased VIP+ cells in the SG, and in contrast to 3 h, VIP-containing nNOS+ cells increased in ODQ+KA when compared to vehicle+KA. In the hippocampus, 7-NI/ODQ had no effect on VIP at 3 h/3 days, while L-NAME+KA at 3 days increased VIP+ cells, but reduced VIP-like immunoreactivity in astrocytes. These results suggest that the NO-cGMP pathway differentially regulates VIP in the DG and hippocampus during seizure.  相似文献   
65.
Aim To establish the rates and types of psychiatric disorder in children before and after surgery for extratemporal epilepsy. Relationships between psychiatric morbidity and demographic/clinical variables were examined. Method A retrospective case note review of 71 children undergoing extratemporal focal resection for drug resistant epilepsy in a specialist epilepsy surgery programme between 1997 and 2008. Psychiatric diagnoses were derived from pre‐ and postoperative assessments according to DSM‐IV criteria. Results Seventy‐one children (38 males, 33 females) were eligible for this study. Mean age (SD) at surgery was 9 (5) years. Frontal resections were performed in 73% of the children, parietal in 17%, and occipital in 10%. Mental health problems were present in 37 of 71 (52%) children pre‐ and/or postoperatively. A similar proportion of children had psychiatric diagnoses pre‐ and postoperatively: 31 of 71 (44%) and 32 of 71 (45%) respectively. Interpretation Psychopathology is common in children with extratemporal epilepsy. In this sample, the impact of surgery on psychiatric symptoms was not predictable: some children were unchanged, others improved, and others acquired new psychiatric diagnoses postoperatively. Given the high rates of psychiatric disorder in this group of patients, detection and treatment of mental health needs may be important.  相似文献   
66.

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   
67.
Background

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.

Method

This 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.

Results

A 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.

Conclusion

In 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   
68.

Introduction

The Predictors study was designed to predict the length of time to major disease outcomes in Alzheimer's disease (AD) patients. Here, we describe the development of a new, Predictors 3, cohort.

Methods

Patients with prevalent or incident AD and individuals at-risk for developing AD were selected from the North Manhattan community and followed annually with instruments comparable to those used in the original two Predictors cohorts.

Results

The original Predictors cohorts were clinic based and racially/ethnically homogenous (94% white, 6% black; 3% Hispanic). In contrast, the 274 elders in this cohort are community-based and ethnically diverse (39% white, 40% black, 21% other; 78% Hispanic). Confirming previous observations, psychotic features were associated with poorer function and mental status and extrapyramidal signs with poorer function.

Discussion

This new cohort will allow us to test observations made in our original clinic-based cohorts in patients that may be more representative of the general community.  相似文献   
69.
70.
Strict isolation of vulnerable individuals has been a strategy implemented by authorities to protect people from COVID-19. Our objective was to investigate health-related quality of life (HRQoL), uncertainty and coping behaviours in solid organ transplant (SOT) recipients during the COVID-19 pandemic. A cross-sectional survey of adult SOT recipients undergoing follow-up at our institution was performed. Perceived health status, uncertainty and coping strategies were assessed using the EQ-5D-5L, Short-form Mishel Uncertainty in Illness Scale (SF-MUIS) and Brief Cope, respectively. Interactions with COVID-19 risk perception, access to health care, demographic and clinical variables were assessed. The survey was completed by 826 of 3839 (21.5%) invited participants. Overall, low levels of uncertainty in illness were reported, and acceptance was the major coping strategy (92%). Coping by acceptance, feeling protected, self-perceived susceptibility to COVID-19 were associated with lower levels of uncertainty. Health status index scores were significantly lower for those with mental health illness, compromised access to health care, a perceived high risk of severe COVID-19 infection and higher levels of uncertainty. A history of mental health illness, risk perceptions, restricted healthcare access, uncertainty and coping strategies was associated with poorer HRQoL in SOT recipients during strict isolation. These findings may allow identification of strategies to improve HRQoL in SOT recipients during the pandemic.  相似文献   
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