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1.
Mannich bases were synthesized and converted to the corresponding arylhydrazones. X-ray analysis of a ketone (1a) and a hydrazone (4d) revealed structural features of interest. All of the compounds showed cytotoxicity toward murine lymphocytic leukemia L1210 cells in the 4.9-25.0-microM range. The correlation coefficients generated by plotting the IC50 values (the concentrations of compounds that inhibit the growth of tumors by 50%) of some hydrazones against certain electronic, hydrophobic, and steric constants of the aryl substituents indicated only weak correlations. A few ketones and hydrazones displayed significant cytotoxicity to the WiDr human colon cancer cells, and these derivatives, especially the ketones, may serve as prototypes for future drug development. The KB tumor (a human epidermoid carcinoma of the nasopharynx) was somewhat refractory to selected compounds. In an in vitro assay conducted by the National Cancer Institute and involving approximately 53 tumor cell lines originating from eight neoplastic diseases, 65% of the compounds showed some selectivity toward one or more groups of cancers, principally leukemia, melanoma, and colon cancer. The bioevaluation of the ketones and hydrazones against the L1210, WiDr, and KB tumors, as well as evidence from proton nuclear magnetic resonance studies did not support the suggestion that hydrazones may be prodrugs of the corresponding ketones.  相似文献   
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BACKGROUND: Somatoform disorders such as neurasthenia and chronic fatigue syndrome are characterized by a combination of prolonged mental and physical fatigue. This study aimed to investigate the heritability of somatic distress and determine whether this dimension is aetiologically distinct from measures of depression and anxiety. METHOD: Measures of anxiety, depression, phobic anxiety, somatic distress and sleep difficulty were administered in a self-report questionnaire to a community-based sample of 3469 Australian twin individuals aged 18 to 28 years. Factor analysis using a Promax rotation, produced four factors: depression, phobic anxiety, somatic distress and sleep disturbance. Multivariate and univariate genetic analyses of the raw categorical data scores for depression, phobic anxiety and depression were then analysed in Mx1.47. RESULTS: Univariate genetic analysis revealed that an additive genetic and non-shared environmental (AE) model best explained individual differences in depression and phobic anxiety scores, for male and female twins alike, but could not resolve whether additive genes or shared environment were responsible for significant familial aggregation in somatic distress. However, multivariate genetic analysis showed that an additive genetic and non-shared environment (AE) model best explained the covariation between the three factors. Furthermore, 33 % of the genetic variance in somatic distress was due to specific gene action unrelated to depression or phobic anxiety. In addition, 74% of the individual environmental influence on somatic distress was also unrelated to depression or phobic anxiety. CONCLUSION: These results support previous findings that somatic symptoms are relatively aetiologically distinct both genetically and environmentally from symptoms of anxiety and depression.  相似文献   
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BACKGROUND: Although depressed patients demonstrate impaired performance on a range of neuropsychological tests, there is little research that examines either frontal cognitive deficits or possible differences in test performance between melancholic and non-melancholic subtypes. METHODS: Depressed subjects were administered a broad neuropsychological battery. In an overall analysis, 77 depressed subjects were compared with 28 controls. In a second set of analyses, the depressed sample was divided into melancholic and non-melancholic subsets according to DSM-III-R, the CORE system and the Newcastle scale. These depressed subsets were contrasted to controls and with each other using ANCOVA controlling for age, IQ, simple reaction time and Hamilton Depression scores where appropriate. RESULTS: The total depressed sample was impaired on most mnemonic tasks, simple reaction time and Trails B. Similar findings applied to DSM-III-R melancholic and non-melancholic subjects. When defined by the CORE and Newcastle (narrower definitions of melancholia), melancholic patients were additionally impaired on WCST (perseverative response) and (for Newcastle) digit symbol substitution. In contrast, the cognitive performance of the CORE and Newcastle-defined non-melancholic patients was largely unimpaired. CONCLUSIONS: Using narrower definitions of melancholia, i.e. CORE and (in particular) Newcastle, melancholic patients were impaired on mnemonic tasks and tasks of selective attention, and set-shifting while non-melancholic subjects were largely unimpaired in their cognitive performance. These differences may be due to impairment of specific neuroanatomical regions in narrowly defined melancholic patients, in particular the anterior cingulate.  相似文献   
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OBJECTIVE: To determine prospectively relationships between minor cerebrovascular episodes and depressive symptoms in a community cohort of older persons. METHOD: In 1988-1989, baseline measurements of vascular risk factors and depressive symptoms were obtained in older community residents (mean age = 67). At 10-year follow-up, three subgroups of subjects still residing in the community were re-assessed: those who had suffered a transient ischaemic attack (TIA) (n = 16) in the intervening period; those with hypertension but no TIAs (n = 38); and, those with neither TIAs nor hypertension (n = 40). RESULTS: Of the 16 persons with depressive symptoms at 10-year follow-up, only three had reported depressive symptoms initially. Subjects who had experienced TIAs during the longitudinal phase had higher rates of depressive symptoms than the subjects from the other two groups (38%vs 13%, p < 0.05). CONCLUSIONS: This study supports the notion that cerebrovascular incidents predispose to late-onset depression in older persons residing in the community. Intrinsically, this provides epidemiological support for the validity of the concept of 'vascular depression'.  相似文献   
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BACKGROUND: Chronic fatigue syndrome is characterized by prolonged and disabling fatigue and a range of neuropsychiatric symptoms including depressed and/or irritable mood. To date, no medical or psychotropic therapies have provided clear symptomatic benefit. METHOD: Ninety patients with chronic fatigue syndrome, diagnosed with our system that approximates CDC criteria, participated in a randomized, placebo-controlled, double-blind trial of 450 to 600 mg/day of moclobemide, a novel reversible inhibitor of monoamine oxidase-A. RESULTS: Fifty-one percent (24/47) of patients receiving moclobemide improved compared with 33% (14/43) of patients receiving placebo (odds ratio = 2.16, 95% confidence interval [CI] = 0.9 to 5.1). Drug response was best characterized symptomatically by an increase in the subjective sense of vigor and energy rather than a reduction in depressed mood. The effect of moclobemide on subjective energy was detectable within the first 2 weeks of treatment and increased across the course of the study. The greatest reduction in clinician-rated disability was in patients with concurrent immunologic dysfunction (mean difference in standardized units of improvement = 0.8, 95% CI = 0.03 to 1.6). CONCLUSION: Moclobemide produces some improvement in key symptoms experienced by patients with chronic fatigue syndrome. This effect is not dependent on the presence of concurrent psychological distress and is likely to be shared with other monoamine oxidase inhibitors.  相似文献   
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