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101.
ABSTRACT

This study investigated whether adolescent's family type was associated with regular smoking or the use of illicit substances (cannabis or hard drugs) among underage adolescent psychiatric in-patients. The sample consisted of 471 adolescents aged 12–17 years admitted to psychiatric hospital between April 2001 and March 2006 at Oulu University Hospital, Finland. The information on family factors and substance use was based on the Schedule for Affective Disorder and Schizophrenia for School-Age Children, Present and Lifetime interview and the European modification of the Addiction Severity Index questionnaire. Compared to adolescent boys from two-parent families, those from child welfare placement were more likely to regularly use both cannabis (odds ratio [OR] = 4.4; 95% confidence interval [CI] = 1.4–13.7; P = .012) and hard drugs (OR = 8.4; 95% CI = 1.7–42.1; P = .01). Among girls, no association was found between family type and the use of illicit substances. Two-parent or foster family units may protect adolescents from involvement with illicit substances. In clinical adolescent psychiatric practice more attention should be paid to family interventions and parental support.  相似文献   
102.
Periodontitis increases the atherosclerosis risk, but information on the role of periodontal pathogens in atherogenesis is limited. In the present study we have investigated, whether the major periodontal pathogen, Aggregatibacter (Actinobacillus) actinomycetemcomitans, induces development of atherosclerosis in apolipoprotein E-deficient mice. The mice received 4, 6, or 8 weekly i.v. injections of live pathogen (10(7)CFU/50 microl/mouse) or saline as control, and were killed 1 week after the last injection. The atherosclerotic lesion formation was examined from whole aortas and aortic sinus cryosections after lipid staining. Neither the lesion area in the aortas or en face analyses, nor their immunoreactivity to the macrophage-marker CD68 differed significantly between the infected and the control mice. However, the pathogen administration increased serum C-reactive protein (CRP) concentrations, and induced proatherogenic lipoprotein profiles with smaller particle sizes in very-low density (VLDL), low density (LDL), and high density (HDL) lipoprotein fractions. It also caused elevated matrix metalloproteinase-9 expression in the aortas and increased serum gelatinase level. Lipopolysaccharide deriving from the pathogen was associated with proatherogenic lipoprotein fractions: VLDL and especially LDL. The results indicate that A. actinomycetemcomitans contributes to disturbed lipoprotein profiles, inflammatory reaction, and matrix remodelling which are known to promote the development of atherosclerosis.  相似文献   
103.
Bright light therapy (BLT) is widely accepted as first-line treatment of seasonal affective disorder (SAD). However, the mechanism of action of BLT is still widely unknown. On the other hand, in mammals, light penetrates the skull bone and reaches the brain, and extra ocular transcranial phototransduction has physiological influences such as changed reproductive cycles and increased brain serotonin levels. Therefore, we challenged the existing conceptual framework that light therapy would only be mediated through the eyes. Consequently, we run a pilot study on the putative effect of transcranial bright light in the treatment of SAD. The light was produced using light-emitting diodes (LEDs), which were attached to earplugs. The amount of photic energy was 6.0-8.5 lumens in both ear canals, and the length of treatment was 8 or 12 min five times a week during a four-week study period. Subjects were recruited through advertisements in the city of Oulu, Finland (latitude 65°01'N) during 14 January 2009-03 February 2009. The final patient series consisted of 13 (aged 37.1 ± 7.2 years) physically healthy indoor workers suffering from SAD according to DSM-IV-TR criteria. Severity of depressive symptoms was assessed using the 17-item Hamilton Depression Rating Scale (HAMD-17) and Beck Depression Inventory (BDI)-21. Furthermore, severity of anxiety symptoms was measured by the 14-item Hamilton Anxiety Rating Scale (HAMA). The HAMD-17 mean sum score at screening was 23.1 ± 1.6. Ten out of 13 SAD patients (76.9%) achieved full remission (i.e., HAMD-17 sum score ≤ 7), and 92.3% (12/13) at least 50% reduction in HAMD-17 sum scores at "Week 4". By using a mixed regression model of repeated measures (AR-1) controlling for age, gender, and HAMD-17 mean sum score at screening, significant differences were found comparing the HAMD-17 mean sum scores of "Week 0" with the corresponding scores at the "Week 3" (t=-2.05, p=0.045) and "Week 4" visit (t=-2.77, p=0.008). Correspondingly, significant differences were found comparing the BDI-21 mean sum scores (15.2 ± 6.7) of "Week 0" with the corresponding scores at the "Week 3" (t=-2.37, p=0.021) and "Week 4" visit (t=-3.65, p<0.001). The HAMA mean sum score at screening was 20.5 ± 5.4. During the study period, 12 out of 13 (92.3%) patients achieved at least 50% reduction in their HAMA sum scores, and in 10 out of 13 patients (76.9%), the HAMA sum score was <7. In conclusion, it is hard to believe that our findings could be explained solely by placebo effect. Consequently, the basic assumptions underlying extraocular photoreception in humans deserve to be reconsidered. Given that a proper placebo treatment can be implemented via ear canals, further investigations with randomized placebo-controlled and/or dose-finding study designs regarding the extraocular transcranial bright light in the treatment of SAD are called for.  相似文献   
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106.
In urethane-anaesthetized rats the administration of imidazole acetic acid (IAA), 34–272 g per rat intracerebroventricularly (i.c.v.), induced a dose-related fall in blood pressure. Rolipram (ZK 62 711), a potent and selective inhibitor of cyclic AMP phosphodiesterase (cAMP-PDE), also lowered the blood pressure in a dose-dependent manner when administered at the doses of 1–64 g per rat i.c.v. A subhypotensive dose of rolipram (0.25 g per rat i.c.v.) did not change the hypotensive effect of IAA. Pretreatment of the rats with metiamide, 1.1. mg per rat i.c.v., shifted the dose-response curve for IAA significantly to the right. The present results make it unlikely that the central hypotensive effect of IAA could be due to the stimulation of cAMP-PDE by this agent. Central histamine H2-receptors may be involved in the hypotensive effect of IAA.  相似文献   
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In the present study, expressions of 17B-hydroxysteroid dehydrogenase (17HSD) types 1, 2 and 3, 5α-reductase type 2 and human androgen receptor mRNAs were determined in 12 benign prostatic hyperplasia and 17 prostatic carcinoma specimens. 17HSD type 2 was found to be the principal isoenzyme expressed in the prostate. Significantly higher expressions of 17HSD type 2 and 5α-reductase type 2 were detected in benign prostatic hyperplasia compared with the carcinoma specimens. Expression of the androgen receptor in the 2 groups was not significantly different. 17HSD type 3 mRNA was not detected in any of the specimens investigated. Only low constitutive expression of the 2.3 kb mRNA of 17HSD type I was seen. Immunohistochemical analyses indicated that this did not lead to significant enzyme expression, only faint staining for the enzyme protein being detected, mainly in uroepithelial cells. No significant correlation was found between any of the mRNAs analyzed, but the data on 5α-reductase type 2 mRNA support the presence of an increased proportion of 5α-dihydrotesterone in the hyperplastic prostate. In cultured PC-3 prostatic cancer cells and in transiently transfected human embryonic kidney 293 cells, 17HSD type 2 was found exclusively to convert 5α-dihydrotestosterone and testosterone into the less potent 17-keto compounds 5α-androstanedione and 4-androstenedione, respectively. We suggest that the 17HSD type 2 isoenzyme plays a part in the metabolic pathway, resulting in the inactivation of testosterone and 5α-dihydrotestosterone locally in the prostate. The enzyme expressed in the prostate could, therefore, protect cells from excessive androgen action. © 1996 Wiley-Liss, Inc.  相似文献   
110.
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