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991.
OBJECTIVE: To examine potential associations of the Glu/Asp(298) polymorphism in exon 7 and the 4a/b polymorphism in intron 4 of the endothelial nitric oxide synthase (eNOS) gene with susceptibility to and clinical expression of giant cell arteritis (GCA), particularly in patients with versus those without ischemic complications. METHODS: Ninety-one consecutive patients with biopsy-proven GCA, who were residents of Reggio Emilia, Italy, and 133 population-based controls from the same geographic area were genotyped by polymerase chain reaction and allele-specific oligonucleotide techniques for eNOS polymorphisms in exon 7 and intron 4. The patients were separated into 2 subgroups according to the presence or absence of ischemic complications (visual loss and/or jaw claudication and/or aortic arch syndrome). RESULTS: The distribution of the Glu/Asp(298) genotype differed significantly between GCA patients and controls (corrected P [P(corr)] = 0.003). Carriers of the Asp(298) allele (Asp/Asp or Glu/Asp) were significantly more frequent among the GCA patients than among the controls (P(corr) = 0.0002, odds ratio 3.3, 95% confidence interval 1.7-6.3). The distribution of the 4a/b genotype was similar in GCA patients and controls. No significant associations were found when GCA patients with and without ischemic complications were compared. CONCLUSION: Our findings show that the Glu/Asp(298) polymorphism of the eNOS gene is associated with GCA susceptibility.  相似文献   
992.
993.
BACKGROUND: After a first episode of venous thromboembolism, patients are treated with vitamin K (phytonadione) antagonists. There are indications that the risk of recurrence after treatment with vitamin K antagonists decreases relative to the time since the first event. The aim of the present meta-analysis is to describe the risk of recurrent venous thromboembolism after treatment with vitamin K antagonist in relation to the time since the index event. METHODS: Computerized searches in MEDLINE and EMBASE databases; reference checks of pertinent articles; personal communication with colleagues to find randomized clinical trials and cohort studies in which patients with venous thromboembolism were treated with vitamin K antagonists. Per treatment arm, 2 reviewers independently extracted data on the number of recurrent events and the duration of follow-up per time period of 3 months. RESULTS: A total of 135 potentially eligible studies were identified. Of these, 18 studies could be included, comprising 25 treatment arms that could be analyzed. Treatment arms were divided into 3 groups based on treatment duration (short, medium, and long). For all 3 groups, the monthly incidence immediately after discontinuation of treatment was high and declined rapidly thereafter. The monthly incidence after 9 months seemed independent of the treatment duration. CONCLUSIONS: There is a diminishing risk of recurrent venous thromboembolism over time and a stabilization after 9 months independent of the duration of the initial treatment with vitamin K antagonists. These findings have important implications for decision making about the optimal duration of treatment with vitamin K antagonists.  相似文献   
994.
The aims of the study were to examine the relationship between long-chain polyunsaturated fatty acid (LCPUFA) status at diagnosis of phenylketonuria (PKU) and neurodevelopment through the first 12 months of life, and to assess whether any difference exists between infants breastfed and bottlefed in the first days of life on the basis of LCPUFA status. Twenty infants with PKU were prospectively examined through the first year of life. Plasma fatty acids were measured in infants at diagnosis. Plasma phenylalanine levels were determined monthly. Main outcome measures were the Bayley Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) at 5 and 12 months of age, and the visual function at 12 months, evaluated by P100 wave latencies with visual evoked potentials. A higher PDI score was associated with higher plasma arachidonic acid at diagnosis (adjusted correlation coefficient of PDI at 5 months, r=0.38, p=0.05). P100 wave latency at 15 minutes of arc (15') was associated with the early plasma arachidonic acid (adjusted r=-0.56, p=0.02) and phenylalanine levels at 12 months (adjusted r=0.22, p=0.05). No association was found between MDI score and any essential fatty acids. Breastfed infants exhibited higher plasma arachidonic acid (mean difference, delta, =3.4%; 95% confidence interval [CI]=1.2-5.6%) and shorter P100 wave latency at 15' (delta=-21 ms, 95%CI=-30 to -12) than bottlefed infants. Within the population of this study, a weak positive association has been found between plasma LCPUFAs at diagnosis (higher in breastfed infants) and neurodevelopmental indices through the first year of life.  相似文献   
995.
Cocaine causes neuroendocrine aberrations in cocaine abusers with pituitary stress hormone secretion providing a window to the stress system in the brain. Substance abusers and control participants were hormonally profiled for 3 weeks. Abusers showed significant basal elevations in prolactin in week 1 with normalization over the 3 weeks. No differences in prolactin secretion were seen with either thyrotropin-releasing hormone stimulation or L-dopa suppression testing. Basal afternoon cortisol secretion was significantly elevated during weeks 1 and 2 comparing abusers to controls. Elevated afternoon cortisol secretion is a sensitive indicator of central stress activation. These results point to the hypothalamus, not the pituitary gland, as being primarily altered in cocaine withdrawal. The data demonstrate that both the dopamine-prolactin and hypothalamic-pituitary-adrenal (HPA) axes are affected during cocaine cessation. As medications are developed to modulate activation of a dysfunctional stress system, future therapeutic studies of substance abuse, withdrawal, craving and relapse should employ more sophisticated tests of hypothalamic pituitary function, especially the HPA axis, as this information may be a guide in the diagnosis and predict clinical responses.  相似文献   
996.
Two white men 57 and 39 years old, and a 47-year-old white woman were seen with slowly developing papulo-nodular lesions of the areola-nipple complex. None of the patients presented with regional lymphadenopathy, history of trauma, or relevant sun-exposure. After excison of the mass, the histologic diagnosis of basal cell carcinoma was made. At two years of follow-up, no recurrence was evident. The low incidence of basal cell carcinoma in this particular site allows us to consider the areola-nipple complex location as unusual. Moreover, literature reports do not suggest that these BCCs have an increased potential for malignancy. The treatment options depend on the extension of the tumor and on the possible involvement of the areola-nipple complex and mammary tissue.  相似文献   
997.
998.
999.
PURPOSE: To evaluate available data on breast conserving surgery (BCS) with or without radiation therapy (RT), and alternative options (e.g. Tamoxifen alone) (Tam), focusing specifically on the older patients. METHODS AND MATERIALS: The MEDLINE was searched for the terms elderly, BCS, adjuvant/postoperative RT, Tamoxifen, and randomized trials from 1992 to 2002. RESULTS: Authors reviewed papers of general interest on the elderly and breast cancer (BC), meta-analysis, randomized trials on BCS+/-RT and Tam+/-surgery without RT, retrospective non-randomized trials, and reported on prognostic factors for local recurrence in BCS alone, including biomarkers, attempts made to define a low-risk group, and methods of modification of the current, protracted standard adjuvant RT course. CONCLUSIONS: Postoperative RT after BCS has a firm rationale; in current clinical practice, if the BCS+RT is medically appropriate and the patient shares the choice, after a full information of the available options and their implications, it is clinically sound to propose this approach. However, there is controversy whether a subgroup of elderly patients could be safely spared: in this setting a randomized trial is clearly warranted.  相似文献   
1000.
Bronchodilator agents are central to the symptomatic management of Chronic Obstructive Pulmonary Disease (COPD), and long-acting inhaled bronchodilators are regarded as more convenient. The role of inhaled corticosteroids still remains controversial, but there is increasing evidence that they may improve FEV(1) and symptoms in the long-term. AIM: of the present small pilot study was to compare Salmeterol & Fluticasone (SM&FP) 50/250 microg bid via a single Diskus inhaler with SM 50 microg bid alone, and with placebo (P) in the treatment of moderate COPD. METHODS: Eighteen moderate COPD patients (53-77 yr, mean basal FEV(1)=49.1% pred.+/-5.0 s.d.; mean FEV(1) reversibility=3.6% bsln+/-3.8 s.d.) treated with theophylline 400 mg/day and beta(2) short acting prn, were divided into three matched groups of six subjects according to a double-blind design, and treated with SM&FP 50/250 microcg, or SM 50 microcg alone, or P via Diskus inhaler bid for 52 weeks. In bsln, after 4, 12, 24, 36 and 52 weeks, FEV(1) (% pred), morning PEF (l/s), the daily symptom score, and the number of exacerbations (compared with the previous year) were considered. Statistics. t-test, anova in each treatment group, and anova among basal values and among the 52 week values were used, being p<0.05 accepted. Also changes (DeltaFEV(1)) from baseline were compared at different control times. RESULTS: The mean number of exacerbations/yr decreased from 3.5+/-0.8 to 1.16+/-0.75 s.d. exacerbation/yr in the SM&FP group (t-test p<0.001); from 3.0+/-0.89 to 2.3+/-0.81 s.d. in the SM group (t-test p=ns); and from 3.16+/-1.16 to 4.16+/-0.75 s.d. in the P group (t-test p=ns).Patients receiving SM&FP showed the highest mean improvement in FEV(1) (+7.3%+/-3.3 s.d.) over the baseline pre-treatment value after 36 weeks of treatment (anova p<0.001), being FEV(1) unchanged after 52 weeks of treatment in SM group (+0.33%+/-2.4 s.d.) and with a substantial decrease following P (-2.6%+/-1.2 s.d.) (anova p<0.001).Morning PEF (l/min) increased in subjects treated with SM&FP (anova p<0.001), while it remained unchanged in SM and P group (in both, anova p=ns).After 52 weeks of treatment, only subjects treated with SM&FP showed a reduction of the daily symptoms score from 3.6+/-0.7 to 2.0+/-0.2 s.d. (anova p=0.008). Daily beta(2) short acting prn consumption was reduced only in SM&FP group from 4.2+/-0.81 to 2.2+/-1.2 s.d. after 52 weeks (anova p<0.001). CONCLUSIONS: SM&FP 50/250 microcg regularly assumed in combination via a single Diskus inhaler for a 52 week period improves respiratory function (such as FEV(1), morning PEF), and and symptom score significantly in moderate COPD previously treated with theophylline, and at an higher extent than SM alone or P. The use of beta(2) short acting prn is also reduced, together with the number of exacerbations.  相似文献   
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