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81.
OBJECTIVE: The aims of this study were to document the incidence of impaired cerebral autoregulation in children with traumatic brain injury using transcranial Doppler ultrasonography and to examine the relationship between autoregulatory capacity and outcome in children following traumatic brain injury. DESIGN: Prospective cohort study. SETTING: Harborview Medical Center (level I pediatric trauma center) in Washington state. PATIENTS: Thirty-six children <15 yrs old with traumatic brain injury: Glasgow Coma Scale score <9 (n = 12, group 1), Glasgow Coma Scale score 9-12 (n = 12, group 2), and Glasgow Coma Scale score 13-15 (n = 12, group 3). INTERVENTIONS: Cerebral autoregulation testing was conducted during extracranial surgery. Mean middle cerebral artery flow velocities were measured using transcranial Doppler as mean arterial pressure was increased to whichever variable was greater: 20% above baseline or a set value (80 mm Hg for <9 yrs and 90 mm Hg for 9-14 yrs). Autoregulatory capacity was quantified by the Autoregulatory Index. Autoregulatory Index <0.4 was considered impaired cerebral autoregulation. Discharge outcome using the Glasgow Outcome Scale score was considered good if the Glasgow Outcome Scale score was > or =4. MEASUREMENTS AND MAIN RESULTS: Twenty-four (67%) of 36 children had an Autoregulatory Index > or =0.4. The incidence of impaired cerebral autoregulation was 42% (five of 12) in group 1, 42% (five of 12) in group 2, and 17% (two of 12) in group 3. Ten (42%) of the 24 children with intact cerebral autoregulation had a good outcome compared with only one of 12 (8%) children with impaired cerebral autoregulation (p =.04). Six of 12 (50%) children with impaired cerebral autoregulation had hyperemia compared with one of 24 (4%) children with intact cerebral autoregulation (p <.01). Hyperemia was associated with poor outcome (p =.01). CONCLUSIONS: The incidence of impaired cerebral autoregulation was greatest following moderate to severe traumatic brain injury. Impaired cerebral autoregulation was associated with poor outcome. Hyperemia was associated with impaired cerebral autoregulation and poor outcome.  相似文献   
82.
This study aims to assess trends in compliance with current colposcopy guidelines in 10 gynaecological units in four English counties since 1996; to identify constraints on compliance and suggest change in practice. All 10 gynaecology units in Oxfordshire, Buckinghamshire, Northamptonshire and Berkshire participated. Data were collected prospectively by colposcopists from 23,500 new referrals across a 55-month period from September 1996 to March 2001. The Oxford Cancer Intelligence Unit performed collation, quality assurance and retrieval of data for incomplete records. Audit results were disseminated annually to colposcopists via the Regional Colposcopy Group. Colposcopy waiting times exceeded the standards, but waiting times for high-grade referrals showed statistically significant improvement. Six standards were achieved; relating to accuracy, appropriateness of management and outcomes. The seven unmet standards relate to waiting times, colposcopist's caseload, follow-up policy and the proportion of cervical epithelial neoplasia (CIN) on histology. Changes in practice are suggested, constraints on compliance are identified and the appropriateness of some guidelines is questioned.  相似文献   
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PURPOSE: Tuberous sclerosis complex (OMIM 191100) is a multiorgan disease commonly associated with epilepsy refractory to anticonvulsants. Individual reports indicate that seizures in children with tuberous sclerosis might benefit from a ketogenic diet. We studied the effects of the diet introduced at 3.5 years of age in three boys with tuberous sclerosis and refractory partial seizures. METHODS: On admission a classical LCT ketogenic diet was initiated and patients were followed for 12 months. Antiepileptic drugs were maintained unless adverse effects required reduction. RESULTS: Two patients became seizure-free within 2 months on the diet. In the third patient drop attacks decreased significantly. On follow-up the diet was well accepted and without adverse effects. CONCLUSION: The ketogenic diet should be considered as a treatment option for children with tuberous sclerosis and partial seizures refractory to anticonvulsants. Our data support the need for further studies in larger cohorts to confirm the effectiveness of the ketogenic diet in this entity.  相似文献   
85.
Dapsone therapy for malaria during pregnancy: maternal and fetal outcomes.   总被引:2,自引:0,他引:2  
The need to consider using dapsone in pregnant women for its antimalarial activity is becoming greater in areas where Plasmodium falciparum resistance to chloroquine and pyrimethamine-sulfadoxine is rapidly increasing. Dapsone in combination with other antimalarials might provide a valuable alternative for both treatment and prophylaxis. This review assesses the clinical pharmacology of dapsone and its adverse drug reactions in relation to haemolysis, glucose-6-phosphate dehydrogenase (G6PD) deficiency, blood dyscrasias and methaemoglobinaemia. Studies are summarised reporting its use in leprosy, dermatological and other conditions, and malaria, in relation to maternal and infant outcomes. A total of 924 pregnancies were identified during which dapsone therapy was taken. Only limited data are available and this precludes a meaningful quantitative benefit-risk analysis.Mild degrees of haemolysis consistently occur with continued therapy, although adverse effects may be less likely with intermittent treatment, as most reported adverse effects have occurred with long-term use of dapsone. There are a number of gaps in knowledge where more data are needed. These include no data on pharmacokinetics in pregnancy and whether these are altered with co-administration of chlorproguanil. Potential complications in women with severe anaemia are unknown and there is no information on haemolytic effects in women or the fetus with G6PD deficiency. The use of dapsone in HIV-infected women in malarious areas could carry increased risks because of the immunosuppressive actions of the drug. Trials of dapsone therapy in pregnancy should be considered in malarious areas where there is good reason for its deployment. Controlled trials have provided data on maternal tolerance, and dapsone in combination with other antimalarial drugs can offer clear benefit in terms of improved birthweight. The use of dapsone combinations should be considered when no good alternative is available and the threat of malaria is the greater risk.  相似文献   
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87.
Individuals with sickle cell disease (SCD) experience cognitive deficits; however, it remains unclear whether medical treatments for SCD improve cognition. Given that executive abilities are typically impaired in individuals with SCD, they were the focus of the current study. Our primary hypothesis was that executive abilities would be higher acutely soon after a blood transfusion in children and young adults with SCD. We used tests from the NIH Toolbox to assess executive abilities in 27 participants with SCD receiving chronic transfusion in comparison to 34 participants with SCD receiving hydroxyurea (HU) and 41 non‐SCD demographically matched controls, all of whom were tested at two time points. Participants in the transfusion group completed cognitive testing within 3 days after a transfusion (soon after transfusion) and then within 3 days before their next transfusion (long after transfusion) over an interval of 3‐7 weeks. We found that executive abilities were significantly poorer for the transfusion and HU groups than for the control group. In support of our primary hypothesis, executive abilities for the transfusion group were significantly better soon after a transfusion compared to long after a transfusion, χ2(1) = 17.8, < .0001. Our results demonstrate that executive abilities were higher acutely following a blood transfusion. These findings have implications for daily functioning, medical decision making, and academic achievement in children and young adults with SCD.  相似文献   
88.
Ramucirumab plus paclitaxel is considered the standard of care in the second-line treatment of gastric carcinoma (GC). The aim of this study was to evaluate plasma vascular endothelial growth factor-A (VEGF-A), VEGF-D, and circulating soluble VEGF receptor-2 (sVEGFR-2) as possible markers of resistance or response to ramucirumab administered with paclitaxel in pretreated metastatic GC patients. Plasma samples were collected at different time points (on days 1 and 15 of the first 3 cycles, at best radiologic response and at disease progression). VEGF-A, VEGF-D and sVEGFR-2 were analysed by ELISA. Correlations of biomarker baseline levels or dynamic changes with outcome measures were assessed. Progression-free survival (PFS) was the primary endpoint of the study. Forty-one patients were enrolled. VEGF-A and VEGF-D, but not sVEGFR-2, values significantly increased during treatment compared to baseline (P < 0.001). A positive correlation between VEGF-A and sVEGFR-2 at cycle 2 was found (P=0.045). At univariate analysis, higher baseline levels of VEGF-A were associated with worse OS (P=0.015). Early increase of sVEGFR-2 levels after the first treatment cycle was the only factor associated with longer PFS (6.6 vs. 3.6 months, P=0.049) and OS (18.6 vs. 5.2 months, P=0.008). Significance of sVEGFR-2 early increase was retained at multivariate analysis for OS (HR 0.32; 95% CI 0.12-0.91; P=0.032). The reported results confirmed the prognostic role of baseline VEGF-A and, with the limitations of the limited sample size and the lack of a control arm, suggested that the early increase of sVEGFR-2 after 1 cycle of treatment could be a potential predictive biomarker of benefit from second-line ramucirumab plus paclitaxel in GC.  相似文献   
89.
Purpose To study the relationship between foveal thickness assessed by optical coherence tomography (OCT) and foveal function measured with multi focal electroretinography (mfERG) in patients with non-proliferative diabetic retinopathy, and with no previous laser treatment. Methods Twenty-six eyes from 18 diabetic patients (13 men), aged 59 years, (range 28–79 years), diabetes duration 15 years, (range 2–27 years), with a macular thickness between 200 and 600 μm were evaluated by mfERG, visual acuity (ETDRS score) and OCT. Mean amplitudes and implicit times of the mfERG responses were analyzed within the four innermost (14 degrees) of the six concentric rings. For comparison with the results from the OCT (diameter of measured area = 6 mm) we analyzed the summed response from the first and second ring (central zone), corresponding to the central area of the OCT. The third(zone 2) and fourth (zone 3)of the four innermost of the six concentric rings measured by the mfERG corresponding to the second and third area of OCT. Results An increased macular thickness in the central area of the OCT correlated to reduced amplitudes (r = −0.541; P = 0.004) and prolonged implicit times (r = 0.548; P = 0.004) in the central zone of the mfERG, and inversely correlated with visual acuity, −0.49; P = 0.045. Retinal thickness in the second area was correlated to prolonged implicit times in the second mfERG zone (r = −0.416; P = 0.034). No correlations were found for the third area of the OCT. When macular thickness exceeded 300 μm the decrease of amplitudes and prolonged implicit times, measured by mfERG, seemed to be more pronounced. Conclusion In conclusion increased macular thickness is correlated with reduced amplitudes and prolonged implicit times on the mf ERG and worse visual acuity.  相似文献   
90.
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