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11.
The hypothalamic–pituitary–adrenal (HPA) axis displays a characteristic circadian pattern of corticosterone release, with higher levels at the onset of the active phase and lower levels at the onset of the inactive phase. As corticosterone levels modify the response to stress and influence the susceptibility to and/or severity of stress-related sequelae, we examined the effects of an acute psychological trauma applied at different zeitgeber times (ZTs) on behavioral stress responses. Rats were exposed to stress either at the onset of the inactive-(light) phase (ZT=0) or at the onset of the active-(dark) phase (ZT=12). Their behavior in the elevated plus-maze and acoustic startle response paradigms were assessed 7 days post exposure for retrospective classification into behavioral response groups. Serum corticosterone levels and the dexamethasone suppression test were used to assess the stress response and feedback inhibition of the HPA axis. Immunoreactivity for neuropeptide Y (NPY) and NPY-Y1 receptor (Y1R) in the paraventricular (PVN) and arcuate (ARC) hypothalamic nuclei, hippocampus, and basolateral amygdala were measured. The behavioral effects of NPY/Y1R antagonist microinfused into the PVN 30 min before stress exposure during the inactive or active phase, respectively, were evaluated. PVN immunoreactivity for NPY and Y1R was measured 1 day after the behavioral tests. The time of day of the traumatic exposure markedly affected the pattern of the behavioral stress response and the prevalence of rats showing an extreme behavioral response. Rats exposed to the stressor at the onset of their inactive phase displayed a more traumatic behavioral response, faster post-exposure corticosterone decay, and a more pronounced stress-induced decline in NPY and Y1R expression in the PVN and arcuate hypothalamic nuclei. Blocking PVN Y1R before stress applied in the active phase, or administering NPY to the PVN before stress applied in the inactive phase, had a resounding behavioral effect. The time at which stress occurred significantly affected the behavioral stress response. Diurnal variations in HPA and NPY/Y1R significantly affect the behavioral response, conferring more resilience at the onset of the active phase and more vulnerability at the onset of the inactive phase, implying that NPY has a significant role in conferring resilience to stress-related psychopathology.  相似文献   
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BACKGROUND: Several reports have suggested that early chest tube drainage (CTD) may not be necessary in the treatment of severe pleural empyema (PE) in pediatric patients if appropriate antibiotic therapy and supportive care are provided. OBJECTIVES: A prospective open study to compare the short-term course of two treatment protocols of severe PE in pediatric patients. STUDY DESIGN: One group of 32 patients was treated with early insertion of a chest tube for CTD, and a second group of 35 patients was treated by a repeated ultrasound-guided needle thoracocentesis (RUSGT). The severity of the empyema was assessed by chest radiograph, the amount of fluid drained, the number of days the patient had experienced a fever, and the duration of antibiotic treatment. RESULTS: No significant differences were found between the two groups (RUSGT vs CTD) in all of the following measurements: mean (plus minus SD) duration of a temperature > or = 39 degreesC, 6.2 +/- 2.4 vs 6.5 +/- 1.8 days, respectively; mean duration of a temperature > or = 38 degreesC, 9 +/- 3.9 vs 8.2 +/- 4.5 days, respectively; fluid drained, 35.1 + 23.8 vs 30 +/- 28.2 mL/kg, respectively; duration of antibiotic treatment, 30 +/- 13.2 vs 30.2 +/- 7.3 days, respectively; and length of hospitalization and home IV treatment, 22 +/- 7.6 vs 24.2 +/- 7.5 days, respectively. A failure to respond to treatment occurred in three patients in the RUSGT-treated group and in five patients in the CTD-treated group. The failure to respond occurred in the RUSGT-treated group only in those patients with very large empyemas that caused mediastinal deviation. CONCLUSION: The treatment of PE by RUSGT is as efficacious as CTD, unless PE causes mediastinal deviation.  相似文献   
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In the course of 6 years, 23 otherwise healthy patients with acute febrile illness and leukopenia were diagnosed as having acute parvovirus B19 infection. Five of these patients had agranulocytosis associated with acute parvovirus B19 infection and one had chronic agranulocytosis due to persistent parvovirus B19 infection. The diagnosis was made after positive anti-parvovirus B19 IgM antibodies were found in all of the patients and viral DNA was detected by PCR in four patients. Neutropenia and agranulocytosis appear to be much more frequently associated with parvovirus B19 infection than previously reported.  相似文献   
15.
Foveal hypoplasia, always accompanied by nystagmus, is found as part of the clinical spectrum of various eye disorders such as aniridia, albinism and achromatopsia. However, the molecular basis of isolated autosomal recessive foveal hypoplasia is yet unknown. Individuals of apparently unrelated non consanguineous Israeli families of Jewish Indian (Mumbai) ancestry presented with isolated foveal hypoplasia associated with congenital nystagmus and reduced visual acuity. Genome-wide homozygosity mapping followed by fine mapping defined a 830 Kb disease-associated locus (LOD score 3.5). Whole-exome sequencing identified a single missense mutation in the homozygosity region: c.95T>G, p.(Ile32Ser), in a conserved amino acid within the first predicted transmembrane domain of SLC38A8. The mutation fully segregated with the disease-associated phenotype, demonstrating an ∼10% carrier rate in Mumbai Jews. SLC38A8 encodes a putative sodium-dependent amino-acid/proton antiporter, which we showed to be expressed solely in the eye. Thus, a homozygous SLC38A8 mutation likely underlies isolated foveal hypoplasia.  相似文献   
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The present study aimed to compare the executive function (EF) of children with neurofibromatosis type 1 (NF1) to those of typically developing children and to investigate whether those abilities could predict the child's academic success in terms of academic skills and enablers. Twenty-nine children with NF1 and 27 age-and-gender-matched controls (aged 8–16 years) were examined with two tests to measure EF in an ecologically valid manner: the Behavioural Assessment of the Dysexecutive Syndrome in Children (BADS-C) and the parent questionnaire for the Behavior Rating Inventory of Executive Function (BRIEF). In order to evaluate academic success we used the Academic Competence Evaluation Scales (ACES). The performance of the NF1 group was significantly lower on the Water and Key search subtest of the BADS-C and on four scales of the BRIEF: initiate; working memory; plan/organise and organisation of materials. Significant correlations and predictive models via regression analysis were generated for: BADS-C, BRIEF and ACES scores. Based on these findings, children with NF1 have executive dysfunction that partially accounts for their difficulties in academic achievements.  相似文献   
18.
The coronavirus 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to more than 160 million infections and 3.5 million deaths globally. Men are disproportionately affected by COVID-19, having more severe disease with higher mortality rates than women. Androgens have been implicated as the underlying cause for more severe disease, as the androgen receptor has been noted to upregulate the cell surface receptors that mediate viral cell entry and infection. Unfortunately, despite testosterone’s potential role in COVID-19 prognosis, androgen deprivation therapy is neither protective nor a treatment for COVID-19. Interestingly, the male reproductive organs have been found to be vulnerable in moderate to severe illness, leading to reports of erectile dysfunction and orchitis. COVID-19 viral particles have been identified in penile and testis tissue, both in live patients who recovered from COVID-19 and post mortem in men who succumbed to the disease. Although sexual transmission remains unlikely in recovered men, moderate to severe COVID-19 infection can lead to germ cell and Leydig cell depletion, leading to decreased spermatogenesis and male hypogonadism. The objective of this review is to describe the impact of SARS-CoV-2 on male reproductive health. There are still many unanswered questions as to the specific underlying mechanisms by which COVID-19 impacts male reproductive organs and the long-term sequelae of SARS-CoV-2 on male reproductive health.  相似文献   
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This pioneering study focuses on differences in self-monitoring between normative youth and youth at-risk for deviant behavior. Self-monitoring is a personality trait for the ability to change behavior in response to different situations. Self-monitoring, and especially sensitivity to the expressive behavior of others (SEB), plays an important role in identity formation, in social adjustment of adolescents to normative or deviant peer groups, and in the development of deviant behavior. The participants included 328 normative and at-risk youth from three age groups. They completed the Juvenile Delinquency Self-Report Questionnaire and the Adolescence Self-Monitoring Scale. A significant difference was found in the level of deviant behavior, where at-risk youth reported higher participation in deviant behavior compared to normative youth. One of the factors of self-monitoring, SEB, was higher among normative than among at-risk youth. An increase in SEB was observed with increasing age. Furthermore, the females’ self-monitoring was higher than that of the males.  相似文献   
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