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21.
Purpose

Bullying is associated with a heightened risk for poor outcomes, including psychosis. This study aimed to replicate previous findings on bullying prevalence in clinical high-risk (CHR) individuals, to assess the longitudinal course of clinical and functional variables between bullied and non-bullied CHR and the association of bullying with premorbid functioning, clinical outcome, transition to psychosis and risk of violence.

Methods

The sample consisted of 691 CHR participants and 96 healthy controls. Participants reported whether they had experienced bullying and how long it had lasted. Assessments included DSM-5 diagnoses, attenuated psychotic symptoms, negative symptoms, social and role functioning, depression, stress, premorbid functioning, and risk of violence. The bullied and non-bullied CHR groups were compared at baseline and further longitudinally on clinical and functioning variables and transition to psychosis.

Results

Bullying was more prevalent among CHR individuals than healthy controls. Bullied CHR had a higher prevalence of PTSD and more severe depression and stress at baseline than non-bullied CHR. There was no impact of bullying on clinical and functional variables over time. Bullying was not related to final clinical status or transition to psychosis. However, bullied participants had poorer premorbid functioning and a greater risk of violence.

Conclusion

While bullying may not impact the likelihood of CHR individuals to transition to psychosis, it may be a risk factor for development of the at-risk state and may be related to a greater risk of violence. Future studies should consider bullying perpetration among CHR individuals.

  相似文献   
22.

Background:

Twin and multiplex family studies have established significant heritability for schizophrenia (SZ), often summarized as 81%. The Consortium on the Genetics of Schizophrenia (COGS-1) family study was designed to deconstruct the genetic architecture of SZ using neurocognitive and neurophysiological endophenotypes, for which heritability estimates ranged from 18% to 50% (mean = 30%). This study assessed the heritability of SZ in these families to determine whether there is a “heritability gap” between the diagnosis and related endophenotypes.

Methods:

Nuclear families (N = 296) with a SZ proband, an unaffected sibling, and both parents (n = 1366 subjects; mean family size = 4.6) underwent comprehensive endophenotype and clinical characterization. The Family Interview for Genetic Studies was administered to all participants and used to obtain convergent psychiatric symptom information for additional first-degree relatives of interviewed subjects (N = 3304 subjects; mean family size = 11.2). Heritability estimates of psychotic disorders were computed for both nuclear and extended families.

Results:

The heritability of SZ was 31% and 44% for nuclear and extended families. The inclusion of bipolar disorder increased the heritability to 37% for the nuclear families. When major depression was added, heritability estimates dropped to 34% and 20% for nuclear and extended families, respectively.

Conclusions:

Endophenotypes and psychotic disorders exhibit comparable levels of heritability in the COGS-1 family sample. The ascertainment of families with discordant sibpairs to increase endophenotypic contrast may underestimate diagnostic heritability relative to other studies. However, population-based studies also report significantly lower heritability estimates for SZ. Collectively, these findings support the importance of endophenotype-based strategies and the dimensional view of psychosis.Key words: schizophrenia, psychosis, endophenotypes, cognition, biomarkers, heritability  相似文献   
23.
We evaluated the discrepancy of endophenotypic performance between probands with schizophrenia and unaffected siblings by paternal age at proband birth, a possible marker for de novo mutations. Pairs of schizophrenia probands and unaffected siblings (N=220 pairs) were evaluated on 11 neuropsychological or neurophysiological endophenotypes previously identified as heritable. For each endophenotype, the sibling-minus-proband differences were transformed to standardized scores. Then for each pair, the average discrepancy was calculated from its standardized scores. We tested the hypothesis that the discrepancy is associated with paternal age, controlling for the number of endophenotypes shared between proband and his or her sibling, and proband age, which were both associated with paternal age. The non-significant association between the discrepancy and paternal age was in the opposite direction from the hypothesis. Of the 11 endophenotypes only sensori-motor dexterity was significant, but in the opposite direction. Eight other endophenotypes were also in the opposite direction, but not significant. The results did not support the hypothesized association of increased differences between sibling/proband pairs with greater paternal age. A possible explanation is that the identification of heritable endophenotypes was based on samples for which schizophrenia was attributable to inherited rather than de novo/non-inherited causes.  相似文献   
24.

Background  

The use of short screening questionnaires may be a promising option for identifying children at risk for depression in a community setting. The objective of this study was to assess the validity of the Short Mood and Feelings Questionnaire (SMFQ) and one- and two-item screening instruments for depressive disorders in a school-based sample of young adolescents.  相似文献   
25.
BACKGROUND: Previous studies document neuropsychological deficits associated with stimulant abuse, but findings are inconsistent. METHODS: We identified 50 twin pairs in which only 1 member had heavy stimulant abuse (cocaine and/or amphetamines) ending at least 1 year before the evaluation. The co-twin control research design controls for familial vulnerability and makes it easier to identify neuropsychological deficits that are consequences of stimulant abuse. Subjects were administered an extensive neuropsychological test battery organized into the following 5 functions: attention, executive functioning, motor skills, intelligence, and memory. RESULTS: Multivariate tests showed that abusers performed significantly worse than nonabusers on functions of attention and motor skills. Within each of these functions, univariate tests showed that abusers performed significantly worse on certain tests of motor skills and attention. In contrast, abusers performed significantly better on one test of attention measuring visual vigilance. Within the abuser group, higher levels of stimulant use were largely uncorrelated with neuropsychological test scores, although a few significant correlations indicated better functioning with more stimulant use. CONCLUSIONS: With ideal controls, this study demonstrates that deficits in attention and motor skills persist after 1 year of abstinence from stimulant use and raises hypotheses regarding relative strengths on a vigilance task among abusers.  相似文献   
26.
Bipolar disease features states of severe depression that usually fluctuate with at least one episode of intense elation or mania. It is a disorder that has been thought for some time to have a heritable component. The lifetime prevalence of bipolar disease in the general population is approximately 1%. In contrast, family studies have shown the approximate lifetime risk of a first-degree relative of a bipolar proband to be 5% to 10%. Moreover, studies of monozygotic twins show that their risk of contracting the disease is as much as 75 times greater than that for the general population. In addition, adoption studies have demonstrated that biological relatives of bipolar patients are substantially more likely to have the disorder than are adoptive relatives.  相似文献   
27.
OBJECTIVE: The goal of this study was to investigate associations between empirically defined dimensions of spirituality, personality variables, and psychiatric disorders in Vietnam era veterans. METHOD: One hundred pairs of male twins from the Vietnam Era Twin Registry were administered the self-report Spiritual Well-Being Scale and a pilot Index of Spiritual Involvement. Correlation analyses were supplemented with regression analyses that examined the relative influence of genetic and environmental factors on aspects of spirituality. RESULTS: Existential well-being was significantly associated with seven of 11 dimensions of personality and was significantly negatively associated with alcohol abuse or dependence and with two of three clusters of personality disorder symptoms. Associations between mental health variables and religious well-being or spiritual involvement were much more limited. CONCLUSIONS: Useful distinctions can be made between major dimensions of spirituality in studies of spirituality, religious coping, and mental health.  相似文献   
28.
29.
Brain perfusion in autism varies with age   总被引:3,自引:0,他引:3  
Our subjects consisted of 14 autistic individuals and 14 controls ranging in age from 3 to 37 years. A (99m)Tc HMPAO single photon emission computed tomogram (SPECT) was used to examine blood flow variations between autistic subjects, compared to an age- and gender-matched control group. We found significant hypoperfusion in the prefrontal areas of autistic individuals as compared to normals in every case (p < 0.01). As the age of the autistic individuals increased the hypoperfusion of verbal-associated areas in the left temporal lobe and frontal areas became more evident. The findings were significant at the p < 0.001 level. The changes in perfusion over time correlated with language development and acquisition as individuals matured. We conclude that autistic individuals have a deficiency in prefrontal areas associated with word identification and language formation skills. This subsequently prevents development of true verbal fluency and development in the temporal and frontal areas associated with speech and communication.  相似文献   
30.
The use of the term "obstetrical complications" (OCs) and its variations to encompass diverse physiological mechanisms (e.g., genetic, ischemic, hemorrhagic, infectious) of disruption to fetal/neonatal brain development has engendered inconsistency, confusion, and controversy. The principal reason is that the term OCs belies the absence of a fully adequate conceptual framework for characterizing neurodevelopmental risk. We propose that neurodevelopmental risk factors for schizophrenia can be assessed more clearly if broad OC scales are replaced by measures representing more homogeneous pathways of disturbed brain development. Using a new OC classification, we found that disordered growth related to hypoxic-ischemic compromise to early brain development may confer an elevated risk of schizophrenia and other adult-onset psychoses, particularly in the presence of familial risk. Abnormal fetal and neonatal brain growth and development in schizophrenia and OCs may also, at least in part, result from genetic factors and could help explain the relation between seemingly inconsistent OCs identified in prior research.  相似文献   
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