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In a hospital setting in Sicily, we assessed a screening instrument developed for a prevalence survey of parkinsonism, peripheral neuropathies, stroke, and epilepsy. The subjects consisted of (1) hospital patients with any of the above-mentioned diseases, to investigate sensitivity; and (2) hospital visitors free of all these diseases, to investigate specificity. The standard for comparison was a clinical evaluation based on specified criteria. Trained interviewers administered the screening instrument, asking subjects to answer symptom questions and to perform simple physical tasks. For the questions and tasks together, the sensitivity estimates were 100% for parkinsonism (n = 21), 96% for peripheral neuropathies (n = 22), 96% for stroke (n = 22), and 96% for epilepsy (n = 22), while the specificity estimate was 86% (n = 21). Analogous estimates were computed for the set of questions, for the set of tasks, and for each question and task individually. Despite limitations in our approach, we concluded that the screening instrument would be adequate for its intended use.  相似文献   
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BackgroundDiagnostic injections are commonly utilized in the workup of painful total knee arthroplasties (TKA), particularly when the diagnosis remains unclear. However, current literature provides limited evidence regarding the utility and prognostic capability of anesthetic injections in this scenario. This study sought to establish the role of diagnostic injections in predicting successful revision TKA.MethodsA retrospective review was conducted on 144 consecutive aseptic revision TKAs receiving diagnostic anesthetic injections. Instability (57.6%) and aseptic loosening (33.3%) comprised most revision etiologies. Patient-reported percentage pain relief after the injection was statistically correlated with KOOS JR, Knee Society Score, UCLA Activity Level, and satisfaction scores.ResultsAbout 74.3% (107/144) of revision TKAs reported >50% pain relief after injection. There were no differences in pain relief based on revision indication (P = .841). Improvement from preoperative activity level was greater in the >50% pain relief group (P = .024). Four-month patient satisfaction did not differ between patients who reported >50% and ≤50% pain relief (67% vs. 66%, P = .130). About 64% of patients who reported >50% pain relief were satisfied at minimum 1-year follow-up, compared with only 47% of those who reported ≤50% pain relief after diagnostic injection (P < .001).ConclusionStudy results show that patients reporting >50% pain relief after diagnostic injection have improvements in activity level and maintain greater satisfaction at minimum 1-year than those reporting ≤50% pain relief. Expectations for improvement after revision TKA should be tempered if diagnostic anesthetic injection yields minimal subjective pain relief.  相似文献   
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OBJECTIVE: To evaluate whether the survival of patients with Parkinson disease (PD) is shorter than that of the general population. DESIGN: Survival was investigated in a cohort of patients with PD previously identified during a population-based prevalence study (prevalence day, November 1, 1987, reference follow-up date, October 31, 1995). The survival of patients with PD was compared with that of a control sample randomly selected from the same population (2 controls for each case, matched for age, sex, and study municipality). The causes of death in the 2 groups were also compared. Both univariate and multivariate survival analyses were performed to investigate the association with disease-related variables. SETTING: A door-to-door 2-phase prevalence survey performed in 3 Sicilian municipalities. PATIENTS: Fifty-nine patients with PD and 118 controls. RESULTS: Patients with PD showed a high risk of death (relative risk, 2.3; 95% confidence interval, 1.60-3.39). Greater age at November 1, 1987, high Hoehn-Yahr score, and lack of levodopa therapy were associated with a lower survival on univariate analysis. Multivariate analysis confirmed the association between shorter survival among patients with PD and greater age on November 1, 1987. One-way analysis of variance indicated a different effect of levodopa therapy according to age. Multivariate analysis did not confirm this finding. Pneumonia was the cause of death most frequently associated with PD. CONCLUSION: This study indicates that patients with PD have a shorter survival time than the general population.  相似文献   
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利用硝苯啶溶液对光不稳定的性质,在波长350nm处测其光照前后的吸收度差值(△A),△A与硝苯啶乙醇溶液浓度在10~60μg/ml范围内呈线性关系。使用本法对硝苯啶片进行了含量测定,并对其类似物进行了干扰试验,排除了组分的干扰。该法的精密度日内为1.3%,日间为1.9%,平均回收率为99.96%。方法简便、快速,不需色谱等分离手段即可达到分析目的,专一性、重复性均较好,是分析硝苯啶制剂的一种新途径。  相似文献   
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Shattil  SJ; Motulsky  HJ; Insel  PA; Flaherty  L; Brass  LF 《Blood》1986,68(6):1224-1231
Epinephrine causes platelet aggregation and secretion by interacting with alpha 2-adrenergic receptors on the platelet surface. Platelet aggregation requires the binding of fibrinogen to a specific receptor on the membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The current studies were designed to examine the effect of occupancy of platelet alpha 2-adrenergic receptors by epinephrine on the expression of fibrinogen receptors and on the aggregation of platelets. The ability of epinephrine to induce the expression of fibrinogen receptors was studied under two different conditions: acute stimulation (less than 1 min) and prolonged stimulation (50 to 90 min), the latter of which is associated with a reduction or "desensitization" of the platelet aggregation response. Expression of the fibrinogen receptor was monitored with 125I-fibrinogen as well as with 125I-PAC-1 (PAC-1), a monoclonal antibody that binds to the glycoprotein IIb-IIIa complex only after platelets are activated. Epinephrine caused an immediate increase in PAC-1 and fibrinogen binding that was dependent on occupancy of the alpha 2-receptor by epinephrine and on the presence of extracellular free Ca (KCa = 30 mumol/L). By itself, 1 mmol/L Mg was unable to support induction of the fibrinogen receptor by epinephrine. However, it did decrease the Ca requirement by about two orders of magnitude. Prolonged stimulation of unstirred platelets by epinephrine led to a 70% decrease in the aggregation response when the platelets were subsequently stirred. Despite their decreased aggregation response, desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due simply to a decrease in fibrinogen receptor expression. Although desensitization was not affected by pretreatment of the platelets with aspirin, it was partially prevented when extracellular Ca was chelated by EDTA during the long incubation with epinephrine. These studies demonstrate that once platelet alpha 2-adrenergic receptors are occupied by epinephrine, extracellular Ca is involved in initiating the aggregation response by supporting the induction of the fibrinogen receptor and the binding of fibrinogen. Furthermore. Ca-dependent reactions subsequent to fibrinogen binding may be necessary for maximal platelet aggregation and are impaired when platelets become desensitized to epinephrine.  相似文献   
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Krigel  R; Liebes  LF; Pelle  E; Silber  R 《Blood》1982,60(1):272-275
Two patients with progressive hairy cell leukemia following splenectomy were treated with low-dose daily chlorambucil. Both had an objective hematologic response as determined by a return to normal hematocrit and platelet count. This was also reflected in the mononuclear cell fraction by the normalization of cholesterol content, cholesterol/phospholipid ratio, and the lymphocyte subpopulations. This article confirms previous reports on the efficacy of chlorambucil in this setting and describes some morphological, and biochemical concomitant events.  相似文献   
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AIM: In patients with type 2 diabetes mellitus (T2DM), combination therapy is usually required to optimize glucose metabolism as well as to help patients achieve aggressive targets for low-density lipoprotein cholesterol (LDL-C) and other lipid parameters associated with cardiovascular risk. The thiazolidinediones (TZDs) are increasingly being used for both their blood glucose-lowering properties and their modest beneficial effects on triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C). Ezetimibe, an intestinal cholesterol absorption inhibitor, has a mechanism of action that differs from that of statins, which inhibit hepatic cholesterol synthesis. We compared the lipid-modifying efficacy and safety of adding ezetimibe to simvastatin, vs. doubling the dose of simvastatin, in TZD-treated T2DM patients. METHODS: This was a randomized, double-blind, parallel group, multicentre study in T2DM patients, 30-75 years of age, who had been on a stable dose of a TZD for at least 3 months and had LDL-C > 2.6 mmol/l (100 mg/dl) prior to study entry. Other antidiabetic medications were also allowed. Following 6 weeks of open-label simvastatin 20 mg/day, patients were randomized to the addition of either blinded ezetimibe 10 mg/day (n = 104) or an additional blinded simvastatin 20 mg/day (total simvastatin 40 mg/day; n = 110) for 24 weeks. Patients were stratified according to TZD type and dose (pioglitazone 15-30 vs. 45 mg/day; rosiglitazone 2-4 vs. 8 mg/day). RESULTS: LDL-C was reduced more (p < 0.001) by adding ezetimibe 10 mg to simvastatin 20 mg (-20.8%) than by doubling the dose of simvastatin to 40 mg (-0.3%). Ezetimibe plus simvastatin 20 mg also produced significant incremental reductions in non-HDL-C (p < 0.001), very low-density lipoprotein cholesterol (p < 0.05) and apolipoprotein B (p < 0.001) relative to simvastatin 40 mg. There were no differences between the groups with respect to changes in TG and HDL-C levels, and both treatments were well tolerated. CONCLUSIONS: Co-administration of ezetimibe with simvastatin, a dual inhibition treatment strategy targeting both cholesterol synthesis and absorption, is well tolerated and provides greater LDL-C-lowering efficacy than increasing the dose of simvastatin in T2DM patients taking TZDs.  相似文献   
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