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11.
OBJECTIVE: To evaluate the dynamics of bacterial contamination of healthcare workers' (HCWs) hands during neonatal care. SETTING: The 20-bed neonatal unit of a large acute care teaching hospital in Geneva, Switzerland. METHODS: Structured observation sessions were conducted. A sequence of care began when the HCW performed hand hygiene and ended when the activity changed or hand hygiene was performed again. Alcohol-based handrub was the standard procedure for hand hygiene. An imprint of the five fingertips of the dominant hand was obtained before and after hand hygiene and at the end of a sequence of care. Regression methods were used to model the final bacterial count according to the type and duration of care and the use of gloves. RESULTS: One hundred forty-nine sequences of care were observed. Commensal skin flora comprised 72.4% of all culture-positive specimens (n = 360). Other microorganisms identified were Enterobacteriaceae (n = 55, 13.8%); Staphylococcus aureus (n = 10, 2.5%); and fungi (n = 7, 1.8%). Skin contact, respiratory care, and diaper change were independently associated with an increased bacterial count; the use of gloves did not fully protect HCWs' hands from bacterial contamination. CONCLUSIONS: These data confirm that hands become progressively contaminated with commensal flora and potential pathogens during neonatal care, and identify activities at higher risk for hand contamination. They also reinforce the need for hand hygiene after a sequence of care, before starting a different task, and after glove removal.  相似文献   
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Poly(oxyethylene)s with dithioster end groups were obtained from mono- and dihydroxyl terminated commercial polymers by reaction with dimethyl chloroacetamide, subsequent thionation of the amide group, and usual conversion of the thioamides into the dithioesters 14, 15 and 20, 21 . The best results were obtained in the syntheses of the S-carboxymethyl dithioesters ( 15 and 21 ). The resulting reactive poly(oxyethylene)s were grafted upon silica tubes and electrophoresis cells, previously activated by aminopropylsilanization. These graftings result in lowering of the surface potential of the tubes and in suppression of the electro-osmosis flow in an electrophoresis cell tested with a TiO2 standard sample.  相似文献   
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We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively. The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations.  相似文献   
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BACKGROUND: This study evaluated the prevalence of the atherogenic metabolic triad and the hypothesis that waist circumference and fasting triglyceride concentrations could be used as screening tools for identification of the atherogenic metabolic triad in a population of heart transplant men. It also evaluated the relationship between the atherogenic metabolic triad and coronary artery disease (CAD). METHODS: In the study group of 83 consecutive male heart transplant patients having their routine annual coronarography, 23 patients (28%) were characterized by the atherogenic metabolic triad defined by the presence of elevated fasting insulin and apolipoprotein B concentrations and by small low-density lipoprotein (LDL) particles. RESULTS: Seventy-seven per cent of patients with waist circumference values >/= 90 cm and with elevated triglyceride levels (>/=2.0 mmol/liter) were characterized by this atherogenic metabolic triad. Patients with the atherogenic metabolic triad were at markedly increased risk of CAD (odds ratio of 25.3, 95% CI: 1.11-577.3, p < 0.04) compared to heart transplant patients without the atherogenic metabolic triad. CONCLUSIONS: About 30% of heart transplant patients showed the features of the atherogenic metabolic triad. Measurement and interpretation of waist circumference and fasting triglycerides could be used among heart transplant patients to early identify men characterized by the presence of elevated fasting insulin and apolipoprotein B concentrations and small LDL particles. The presence of the atherogenic metabolic triad identified patients at high risk of CAD even in the heart transplant population.  相似文献   
16.
This study was undertaken to evaluate changes in relative (99m)Tc-hydrazinonicotinamide (HYNIC)-annexin V tumor uptake over time in patients undergoing chemotherapeutic treatment at baseline and at 5-7 h and 40-44 h after treatment initiation. Imaging results are related to clinical outcomes, as assessed with response evaluation criteria in solid tumors (RECIST). METHODS: We prospectively included 20 patients (11 men and 9 women; mean age, 59.8 y; range, 22-75 y) scheduled for chemotherapy (n = 19) or bisphosphonate treatment (n = 1). Curable disease was present in 5 patients. The other patients had metastatic disease and were treated in a palliative setting. Three of the 20 enrolled patients were excluded from analysis: 1 patient ultimately refused the proposed chemotherapy treatment; because of difficulties with the labeling procedure, 1 patient did not receive a pretreatment scan; and 1 patient presented with an allergic reaction (rash and nausea) to the (99m)Tc-HYNIC-annexin V formulation. The remaining 17 patients underwent 3 scintigraphic scans with (99m)Tc-HYNIC-annexin V: before treatment and 5-7 h and 40-44 h after treatment initiation. The tumor response was evaluated with RECIST and related to observed changes in the ratios of tumor activity to background activity for the largest known lesion; values exceeding 25% the baseline value on either the 5- to 7-h scan or the 40- to 44-h scan were considered significant. RESULTS: With the proposed sequential imaging protocol and a 25% change threshold, responders to treatment could be separated from nonresponders with a 94% accuracy (16/17 patients). CONCLUSION: Sequential (99m)Tc-HYNIC-annexin V imaging may allow for assessment of the response to chemotherapy within 3 d after treatment initiation.  相似文献   
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BACKGROUND: Coronary vasculopathy is the main cause of cardiac graft failure. Because yearly coronary angiography is invasive in children, a non-invasive method for detecting graft vasculopathy is needed. The aim of this study was to test dobutamine-stress echocardiography in a pediatric population to determine its feasibility, safety and reliability in the detection of graft coronary artery disease. METHODS: Eighteen patients, aged 2 days to 16.8 years at transplantation (mean 8.4 years), underwent 44 dobutamine-stress echocardiography (DSE) exams, at a follow-up of 1.1 to 11.8 years (mean 5.1 years). Selective coronary angiography was performed for comparison. Echocardiographic recordings were obtained in 4 standard views of the left ventricle and measurements carried out within the frames of a 16-segment model. Segmental scores of contractility were obtained for each segment and a total segmental contractility index was calculated at each stage. RESULTS: All patients reached the maximum dose stage. Maximum heart rate was 57% to 90% of predicted maximum. Maximum systolic blood pressure reached 190 mmHg. Segmental scores were normal in 37 and abnormal in 7 cases. Echographic results were concordant with angiography in 82% and discordant in 18% of the cases (4 negative DSEs with minor angiographic lesions, 2 positive DSEs with normal angiography), but there was no significant angiographic lesion with normal DSE. CONCLUSIONS: DSE is a safe and highly feasible non-invasive technique in transplanted children. A normal DSE study successfully predicts the absence of significant coronary artery disease in the post-transplant population.  相似文献   
20.
Previous data indicate that learning of a conditioned visual avoidance task following simultaneous complete bilateral occipital ablations is affected by the age of the organism as well as the postoperative recovery period. The present study investigated the performance of the avoidance task, following complete occipital ablations, in young and older rats given two different recovery intervals. Young rats given 10 days to recover performed more poorly than the young control animals; given 20 days to recover, young rats performed comparable to controls. Older rats given 10 days to recover performed significantly better than the controls; given 20 days to recover, older rats did not show a decrease in performance. The present finding is consistent with previous data which show that the occipital cortex exerted an inhibitory effect on the learning ability of the avoidance task in older rats, which, upon removal, enhanced the performance of these rats on the task.  相似文献   
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