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1.
Fifty-one children (median age: 4.5 years; 4 months-16 years) diagnosed with rhabdomyosarcoma were treated in our center between 1980-1999. The primary sites were head and neck in 31.4%, the genito-urinary system in 21.6%, and extremities in 9.8% of the patients. The histopathologic subtypes were embryonal in 80.4%, alveolar in 9.8%, and undifferentiated in 9.8%. The majority of the patients were considered group III (47%) and group IV (25.5%) according the criteria of the Intergroup Rhabdomyosarcoma Study (IRS). Primary total tumour resection was performed in only 27.5% of the patients. The patients were treated with assigned regimens of IRS II and IRS III protocols. Radiotherapy was applied to 92.1% of the patients. Thirty-four patients (66.7%) were lost to follow up, and of the remaining 17 patients, 7 patients (41.2%) died, relapse occurred in 9 patients (52.9%) and 10 patients (58.8%) are alive. The percentage of cases lost to follow up during the first 10 years and the following 9 years of the study were 77.4% and 50%, respectively. In compliance with cancer treatment remains a major problem in developing countries.  相似文献   
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The effects of age, gender, and hand dominance on bowing of the flexor retinaculum, used in diagnosing carpal tunnel syndrome, were analyzed. Forty men aged 23–58 years old (39.7±11.2) and 40 women aged 20–57 years old (39.6±11.3) were the normal subjects. A total of 160 wrists was examined with a linear array transducer. Bowing of the flexor retinaculum was measured as the distance from a line drawn between the trapezium and the hamate to the palmar apex of the outer surface of the flexor retinaculum. It was 0.5–3.7 mm (2.00±0.64) for all hands, 0.6–3.7 mm (2.06±0.62) for men, 0.5–3.4 mm (1.96±0.67) for women, 0.5–3.4 mm (1.00±0.64) for dominant, and 0.6–3.7 mm (2.03±0.65) for nondominant hands. There was no difference between genders or dominant vs nondominant hands regarding this parameter. However, it was highly correlated with age (r=0.59, p<0.0001). In conclusion, bowing of the flexor retinaculum measurements should be carefully compared with the standardized values when diagnosing carpal tunnel syndrome.  相似文献   
3.
BACKGROUND: Ventilator-associated pneumonia is the leading nosocomial infection in critically ill patients. The frequency of ventilator-associated pneumonia caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia. The authors, therefore, evaluated factors associated with selected multidrug-resistant ventilator-associated pneumonia in critical care patients. METHODS: The authors prospectively recorded potential risk factors at the time of intensive care unit admission. An endotracheal aspirate was obtained in all patients who met clinical criteria for pneumonia. Patients were considered to have ventilator-associated pneumonia only when they met the clinical criteria and aspirate culture was positive for bacteria 48 h or more after initiation of mechanical ventilation. Pediatric patients were excluded. Adult patients with ventilator-associated pneumonia were first grouped as "early-onset" (< 5 days) and "late-onset," determined by episodes of ventilator-associated pneumonia, and then, assigned to four groups based on the bacteria cultured from their tracheal aspirates: Pseudomonas aeruginosa, Acinetobacter baumanii, methicillin-resistant staphylococci, and all others. The first three bacteria were considered to be multidrug resistant, whereas the others were considered to be antibiotic susceptible. Potential risk factors were evaluated with use of univariate statistics and multivariate regression. RESULTS: Among 486 consecutive patients admitted during the study, 260 adults underwent mechanical ventilation for more than 48 h. Eighty-one patients (31%) experienced 99 episodes of ventilator-associated pneumonia, including Pseudomonas(33 episodes), methicillin-resistant staphylococci (17 episodes), Acinetobacter(9 episodes), and nonresistant bacteria (40 episodes). Sixty-six of these episodes were early onset and 33 episodes were late onset. Logistic regression analysis identified three factors significantly associated with early-onset ventilator-associated pneumonia caused by any one of the multidrug-resistant bacterial strains: emergency intubation (odds ratio, 6.4; 95% confidence interval, 2.0-20.2), aspiration (odds ratio, 12.7; 95% confidence interval, 2.4-64.6), and Glasgow coma score of 9 or less (odds ratio, 3.9; 95% confidence interval, 1.3-11.3). A. baumanii-related pneumonia cases were found to be significantly associated with two of these factors: aspiration (odds ratio, 14.2; 95% confidence interval, 1.5-133.8) and Glasgow coma score (odds ratio, 6.0; 95% confidence interval, 1.1-32.6). CONCLUSIONS: The authors recommend that patients undergoing emergency intubation or aspiration or who have a Glasgow coma score of 9 or less be monitored especially closely for early-onset multidrug-resistant pneumonia. The occurrence of aspiration and a Glasgow coma score of 9 or less are especially associated with pneumonia caused by A. baumanii.  相似文献   
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PURPOSE

We aimed to determine the prevalence of paratracheal air cysts (PTACs) and the relationship of PTACs with emphysema and bronchiectasis through retrospective analysis of multidetector computed tomography (MDCT) findings.

METHODS

MDCT findings of 1027 consecutive patients who underwent routine thorax examination between January 2012 and January 2013 were evaluated retrospectively for the presence of PTACs. Localization of the PTACs, as well as their size, shape, and relationship with the trachea were examined. Presence of emphysema and bronchiectasis was recorded, and bronchiectasis severity index was calculated when present. We randomly selected 80 patients who had no visible PTACs as the control group. The findings of patients with and without PTACs were compared.

RESULTS

PTACs were determined in 82 of 1027 patients (8%), in 8.8% of females and 7.3% of males. The presence of PTACs was determined to be independent of gender (P = 0.361). Eighty-one PTACs (98.8%) were located in the right side of the trachea and 56.1% had a tracheal connection. The presence of PTACs significantly correlated with the presence and severity of bronchiectasis (P = 0.001 and P = 0.005 respectively). There was no significant relationship between the presence of PTACs and the presence of emphysema on CT images (P = 0.125).

CONCLUSION

The prevalence of PTACs was determined as 8% in this study. There was significant association between PTACs and bronchiectasis.Paratracheal air cysts (PTACs) are small collections of air adjacent to the trachea at the level of the thoracic inlet (1). Pathological diagnosis of PTACs in surgically confirmed cases includes tracheal diverticulum, lymphoepithelial cyst, and bronchogenic cyst (13). These cysts are covered with ciliary columnar epithelium and connected with the trachea (4). The majority of PTACs are reported as tracheal diverticula in the literature, due to their connection with the trachea (2). The thoracic inlet between the cartilage and muscle layers in right posterolateral wall of the trachea is the most common location for PTACs. A relationship may be seen between an isolated PTAC and the trachea l lumen (5). These lesions may cause recurrent infections by acting as a reservoir for secretions.Occasionally, PTACs can be confused with other causes of extraluminal air collections as laryngocele, pharyngocele, Zenker’s diverticulum, apical hernia of the lung, mediastinal air, apical paraseptal blebs, or bullae. To distinguish PTACs from other pathologies, its typical location in the right posterior paratracheal region at the thoracic inlet can be helpful: PTACs locate away from the lung pleura, communicate with the trachea and have rounded margins that can be differentiated from emphysematous changes (6).PTACs are usually discovered incidentally on thorax computed tomography (CT). They may be associated with a chronic cough or chronic obstructive pulmonary diseases (COPD). The reported prevalence of PTACs ranges from 0.75% to 8.1% (4, 68). There have been a limited number of studies reporting the incidence of PTACs related to COPD or emphysema as detected by CT, and the reported results are variable (4, 6, 811). The relationship between PTACs and pulmonary emphysema or bronchiectasis is still unclear. To our knowledge, no published study has evaluated the relationship between PTACs and bronchiectasis, using a bronchiectasis severity index and objective measures to determine the extent of bronchiectasis on CT images.The purpose of our study was to evaluate the prevalence and characteristics of PTACs, as well as their relationship with bronchiectasis and emphysema, on thorax CT scans.  相似文献   
7.
Insulin resistance is common in women with polycystic ovary syndrome (PCOS). Muscle is the major tissue utilizing glucose while excess adipose tissue relates to insulin resistance. Thus, body composition is likely to be an important regulator of insulin sensitivity. Thirty-nine PCOS patients (age: 29.9 ± 1.0 years; BMI: 33.8 ± 1.2 kg/m2) participated in a cross sectional study. Body composition was measured by dual energy x-ray absorptiometry (DEXA). Insulin resistance and secretion were assessed using oral glucose tolerance test (OGTT) and frequently sampled intravenous glucose tolerance test (FS-IVGTT). In contrast with the conventional expectations, lean mass correlated directly (P < .05) with the insulin resistance measure HOMA (r = 0.440); and inversely with the insulin sensitivity index QUICKI (r = ?0.522) independent of fat mass. In 11 pairs of subjects matched for fat mass (35.6 ± 2.2 and 35.6 ± 2.4 kg) but with discordant lean mass (52.8 ± 1.8 vs 44.4 ± 1.6 kg), those with higher lean mass had a higher glucose response during OGTT (AUCGlucose; P = .034). In contrast, 17 pairs matched for lean mass (48.7 ± 1.7 and 48.9 ± 1.6 kg) but discordant for fat mass (43.3 ± 2.6 vs 30.3 ± 8.9 kg) showed no differences in insulin resistance parameters. These novel findings indicate that lean mass relates directly to insulin resistance in PCOS.  相似文献   
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Intrauterine ischemia of the limbs is a rare condition involving thrombosis and ischemia of the extremities before birth. The clinical presentation depends on the extremity affected as well as the timing of thrombosis. Very few cases with extremity hypoperfusion and gangrene due to intrauterine thrombosis have been reported in the literature, and therefore there is no consensus on the optimal therapeutic strategy for such cases. Presented here is a case of a newborn with intrauterine brachial arterial thrombosis of the right upper extremity who was successfully treated by a combination of recombinant tissue plasminogen activator, enoxaparin and collagenase application followed by surgery.  相似文献   
10.
Nontransfusion-dependent thalassemia (NTDT) patients may develop iron overload and its associated complications despite receiving only occasional or no transfusions. The present 1-year, randomized, double-blind, placebo-controlled THALASSA (Assessment of Exjade in Nontransfusion-Dependent Thalassemia) trial assessed the efficacy and safety of deferasirox in iron-overloaded NTDT patients. A total of 166 patients were randomized in a 2:1:2:1 ratio to starting doses of 5 or 10 mg/kg/d of deferasirox or placebo. The means ± SD of the actual deferasirox doses received over the duration of the study in the 5 and 10 mg/kg/d starting dose cohorts were 5.7 ± 1.4 and 11.5 ± 2.9 mg/kg/d, respectively. At 1 year, the liver iron concentration (LIC) decreased significantly compared with placebo (least-squares mean [LSM] ± SEM, -2.33 ± 0.7 mg Fe/g dry weight [dw], P = .001, and -4.18 ± 0.69 mg Fe/g dw, P < .001) for the 5 and 10 mg/kg/d deferasirox groups, respectively (baseline values [means ± SD], 13.11 ± 7.29 and 14.56 ± 7.92 mg Fe/g dw, respectively). Similarly, serum ferritin decreased significantly compared with placebo by LSM -235 and -337 ng/mL for the deferasirox 5 and 10 mg/kg/d groups, respectively (P < .001). In the placebo patients, LIC and serum ferritin increased from baseline by 0.38 mg Fe/g dw and 115 ng/mL (LSM), respectively. The most common drug-related adverse events were nausea (n = 11; 6.6%), rash (n = 8; 4.8%), and diarrhea (n = 6; 3.6%). This is the first randomized study showing that iron chelation with deferasirox significantly reduces iron overload in NTDT patients with a frequency of overall adverse events similar to placebo.  相似文献   
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