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41.
42.
We assessed the safety of the endoluminal brush technique for the in situ diagnosis of central-venous-catheter (CVC)-related bloodstream infection (CRBSI). The endoluminal brush was used to investigate patients with suspected CRBSI by sampling the CVC lumen to within 3-5 cm of the catheter tip (the brush was kinked to mark the length required). Quantitative peripheral blood cultures were taken 1 min pre-brushing and 1 min and 1h post-brushing. In addition, a 1 mL sample of through-catheter blood was aspirated immediately pre- and post-brushing, and aliquots were directly plated on to blood agar to determine the load of CVC-associated bacteria. After CVC removal, catheter tips were sent for culture using the Maki roll and modified Cleri flush techniques. Of 139 suspected cases, 61 (45%) had confirmed episodes of CRBSI. No patients experienced fever or rigors, or had evidence of embolic phenomena after CVC endoluminal brushing. There was no difference overall in pre-brushing and 1-min post-brushing peripheral blood bacterial counts (P < 0.702). Peripheral and CVC blood bacterial counts were significantly reduced 1h post-brushing (P < 0.03 and P < 0.001, respectively), possibly due to removal of endoluminal biomass. The endoluminal brush technique can be safely used to diagnose CRBSI without the need for CVC removal, provided that the brush is not allowed to protrude beyond the tip of the catheter.  相似文献   
43.
Two coaxial, ambiguously rotating objects tend to be perceived as corotating. Such grouping could be the consequence of bottom-up, cooperative interactions between the stimuli, or the top-down selection of object properties consistent with a model of the objects or scene. However, we find that the coupling between an ambiguous and unambiguous object is sharply reduced, presenting a challenge for both explanations of grouping. We describe experiments that support the idea that top-down feedback is necessary to select and stabilize a perceptual interpretation for ambiguous figures. Reduced coupling between objects of differing ambiguity can be explained if the feedback is global and proportional to ambiguity.  相似文献   
44.

OBJECTIVES:

To determine patterns of follow-up and prenatal education by family physicians and to assess whether practice patterns comply with the 1996 Canadian Paediatric Society/Society of Obstetricians and Gynecologists of Canada (CPS/SOGC) guidelines for early neonatal discharge.

DESIGN:

Mail survey.

SETTING:

A community of 300,000 people who were served exclusively for obstetrical care by a tertiary care hospital that performs 5000 deliveries per year and provides an early discharge program (EDP).

PARTICIPANTS:

Family physicians who provide prenatal and/or newborn care.

MAIN OUTCOME MEASURES:

The timing of neonatal follow-up and parental teaching by family physicians.

RESULTS:

Thirty-two per cent of the respondents scheduled their first postnatal visits two or more weeks after early discharge. There was no significant difference (P=0.7) in scheduling of follow-up for babies who were part of an EDP compared with those who were not. Fewer than 20% of physician respondents provided antenatal education in preparation for early discharge.

CONCLUSIONS:

The 1996 CPS/SOGC guidelines for physician follow-up after early neonatal discharge and for anticipatory parental education are not being followed consistently; however, these guidelines were disseminated without reinforcement. Until further study supports a change in practice guidelines, appropriate implementation strategies must be employed to ensure compliance.  相似文献   
45.
PURPOSE: To evaluate the imaging characteristics of an amorphous silicon flat-panel detector (FPD) for digital chest radiography. MATERIALS AND METHODS: The 41 x 41-cm digital FPD is constructed on a single monolithic glass substrate with a structured cesium iodide scintillator layer and an amorphous silicon thin-film transistor array for image readout. Basic imaging characteristics of the FPD and associated image processing system were assessed on acquired images, including linearity, repeatability, uniformity of response, modulation transfer function (MTF), noise power spectrum, detective quantum efficiency (DQE), contrast sensitivity, and scatter content. Results with the FPD system were compared to those with a storage phosphor computed radiography (CR) system. RESULTS: Images obtained with the FPD demonstrated excellent uniformity, repeatability, and linearity, as well as MTF and DQE that were superior to those with the storage phosphor CR system. The contrast and scatter content of images acquired with the FPD were equivalent to those acquired with the storage phosphor system. CONCLUSION: The FPD provides radiographic images with excellent inherent physical image quality.  相似文献   
46.
Three sibs all presented in the early neonatal period with a salt-losing syndrome. The salt-losing form of congenital adrenal hyperplasia was diagnosed and appropriate treatment with glucocorticosteroids, mineralocorticosteroids, and additional dietary salt started. Although early life was maintained with difficulty, with age all 3 children required decreasing amounts of replacement steroids to maintain normal plasma electrolyte balance. They were reinvestigated at the ages of 15 years and 8 years (twins), when cortisol synthesis and metabolism proved normal, but aldosterone synthesis was blocked by deficiency of 18-dehydrogenase. Rational treatment of these cases of a salt-losing syndrome in which aldosterone synthesis alone is blocked due to lack of the enzyme 18-dehydrogenase requires the administration of a mineralocorticosteroid drug only. Since deoxycorticosterone (acetate or pivalate) requires intramuscular administration, as life-long therapy oral fludrocortisone is preferable. Although fludrocortisone has glucocorticoid activity, the "hydrocortisone equivalent" effect of the small dosage used was unlikely to inhibit either pituitary corticotrophin or growth hormone production.  相似文献   
47.
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids.  相似文献   
48.
49.
During 2012, global detection of a new norovirus (NoV) strain, GII.4 Sydney, raised concerns about its potential effect in the United States. We analyzed data from NoV outbreaks in 5 states and emergency department visits for gastrointestinal illness in 1 state during the 2012–13 season and compared the data with those of previous seasons. During August 2012–April 2013, a total of 637 NoV outbreaks were reported compared with 536 and 432 in 2011–2012 and 2010–2011 during the same period. The proportion of outbreaks attributed to GII.4 Sydney increased from 8% in September 2012 to 82% in March 2013. The increase in emergency department visits for gastrointestinal illness during the 2012–13 season was similar to that of previous seasons. GII.4 Sydney has become the predominant US NoV outbreak strain during the 2012–13 season, but its emergence did not cause outbreak activity to substantially increase from that of previous seasons.  相似文献   
50.
From 1 July 1987 to 31 December 1988, a total of 317 animals (91% of which were dogs) were confirmed to have rabies in Hermosillo, Mexico. The median age of rabid dogs was 1 year, 69% were male, and 98% were owned. The epizootic started in the southern areas of the city, rapidly involved the entire city, and persisted mainly in lower socioeconomic status areas. The area of the city and mean household size were significant predictor variables for the population density of rabid dogs around household clusters (Poisson linear regression, P < 0.001 and P = 0.03, resp). Approximately 2.5% of city residents were bitten by dogs in 1987, with the rate of reported dog bite injuries being positively correlated with mean household size and the proportion of households that owned dogs. Visits to the city health centre for evaluation of possible exposures to rabies increased by 135% after the start of the epizootic; approximately 273 per 100,000 city residents were administered a full or partial course of rabies post-exposure prophylaxis in 1987. Children were at greatest risk for exposures to rabies, accounting for 60% of all reported animal bite injuries evaluated at the health centre. Also they were more likely than older persons to have received bite injuries to the head, face, and neck (odds ratio = 21.6, 95% confidence interval = 5.4, 186.5).  相似文献   
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