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991.
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OBJECTIVE: To measure the time currently spent by primary care practice personnel, and the examination room occupancy time for childhood influenza vaccination visits, to assess the practicality of annual influenza vaccination of all preschool children. SETTING: Seven primary care practices serving one fourth of the children living in Rochester, NY. PATIENTS: Ninety-two children seen for influenza vaccination visits in the 2000-2001 vaccination season. METHODS: Using a standardized protocol, practice staff measured the time spent on check-in, nurse or physician examination, and the actual influenza vaccination process. Waiting and "hands-on" times were determined, as well as total visit and room occupancy times. Nonparametric tests and multivariable models were used to analyze the time spent for components of the visits and to compare time spent by different age groups and practice types (suburban or urban). RESULTS: The median duration of the influenza vaccination visit was 14 minutes (25th to 75th percentiles range, 9-25 minutes) across the 7 practices, with visits to urban practices being longer (22 minutes) than visits to suburban practices (9 minutes). Eighty percent of patient time involved waiting, primarily in examination rooms. The major components of influenza vaccination visits included waiting room time (4 minutes in suburban practices vs 8 minutes in urban practices; P<.01), and time in the examination room (5 minutes vs 14 minutes, respectively; P<.001), during which only 1 to 2 minutes (for both suburban and urban practices) were for hands-on vaccinations. Only 5% of visits were examined by a physician or nurse practitioner. Visit times did not vary by age. CONCLUSIONS: Although the personnel time for influenza vaccination visits was short, there was substantial patient waiting and long occupancy of examination rooms. If universal influenza vaccination is to be efficiently managed in primary care practices, it may be necessary to implement "vaccination clinics" or sessions in which large numbers of children are scheduled for influenza vaccinations at times when adequate rooms and dedicated nursing staff are available.  相似文献   
993.
BACKGROUND: Certain mother-child feeding patterns (MCFPs) may promote childhood obesity and/or disordered eating. OBJECTIVES: To assess the demographic correlates of MCFPs and to test whether differences in MCFPs are associated with child body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters) z scores in a population-based study. DESIGN: A secondary analysis of the National Longitudinal Survey of Youth main and child cohorts was conducted on more than 1000 Hispanic, African American, and non-Hispanic/non-African American children, aged 3 to 6 years. The MCFPs were measured by means of 3 interview questions probing mother-allotted child food choice, child compliance during meals, and child obedience during meals. RESULTS: Mothers of non-Hispanic/non-African American children allotted greater food choice than mothers of African American or Hispanic children. Maternal BMI and other demographic measures were unrelated to MCFPs. The lowest levels of mother-allotted child food choice and child eating compliance were associated with reduced child BMI, with mean BMI z scores of -0.36 and -0.41, respectively. Effect sizes were small, however, and MCFPs did not discriminate children who were overweight or at risk for being overweight from children who were not (P>.05). CONCLUSIONS: Feeding strategies providing the least child food choice were associated with reduced child BMI. However, MCFPs did not relate to child overweight status.  相似文献   
994.
An inhibitor of interferon antiviral activity, which is absent in healthy HIV-seronegative persons, was detected in the sera of all 29 HIV-seropositive study participants. The relationship of the level of interferon inhibitor to CD4 count and HIV-RNA copy number was statistically significant in distinct models. Levels of interferon inhibitor declined by an average of 41-60% in patients who underwent a change in anti-retroviral therapy. Interferon inhibitor levels appear to decline as CD4 cell count rises and HIV-RNA levels fall. This suggests that interferon inhibitor may have a significant role in the host immune response to HIV infection.  相似文献   
995.
A comprehensive survey to document the presence of free-living amoebae was conducted along 58 km of James River, near Richmond, Virginia, USA. Sites included tidal and non-tidal freshwater areas, near 40 combined sewer outflows, three municipal wastewater treatment plant release sites, and thermal discharge from a coal-fired power plant. Amoebae were present on all collection dates, spring through autumn, and at all sites ( n=330). Five genera, Naegleria, Vannella, Acanthamoeba, Vahlkampfia, and Hartmannella were present in both the water column and sediment. The most common isolates from the water column were Naegleria and Vannella. Water conditions conducive to the presence of large quantities of fecal coliform bacteria were correlated with the prevalence of free-living amoebae. Some of the amoebae in this complex ecosystem can act as opportunistic pathogens, may play a role in diseases of aquatic organisms in this heavily urbanized river, and may present a risk to human health.  相似文献   
996.
All clinically and ultrasonographically suspected examples of intraductal papillary-mucinous neoplasm (IPMN) aspirated during a 17-month period were reviewed and analyzed for follow-up. We identified 18 cases of suspected IPMN in patients 52 to 87 years old. All patients had dilated pancreatic ducts, with 3 showing sonographically apparent intraductal papillary lesions; 5 had adjacent cystic or solid pancreatic masses. Cytologic preparations showed thick, glistening, viscid, abnormal mucus in all cases. Aspirates from 13 lesions (72%) were acellular or sparsely cellular, but entrapped single or loosely cohesive neoplastic cells were identified in 16 cases (89%). Goblet cell morphologic features were common (6/18 [33%]), but papillary clusters and dysplastic changes were infrequent (3 [17%] each). In keeping with current therapeutic thinking, confirmatory histologic follow-up was available for only 4 patients (22%), as most people with lesions clinically, sonographically, and cytologically consistent with IPMN are elderly and often have comorbid conditions. Although endoscopic ultrasound-guided fine-needle aspiration has important limitations, gross and cytologic findings can aid in confirming the suspected diagnosis, and integration of complete clinical, sonographic, and cytologic information may be the best way to reach the most accurate diagnosis possible.  相似文献   
997.
A new poly(ethylene glycol)-based copolymer containing multiple thiol (-SH) groups was cross-linked in situ to form a polymer hydrogel under mild conditions. No organic solvent, elevated temperature, or harsh pH is required in the formulation or patient administration processes, making it particularly useful for delivery of fragile therapeutics, such as proteins. The in vitro release of fluorescein-labeled bovine serum albumin and the in vivo release of the model proteins, erythropoietin, RANTES and three PEG-conjugated RANTES derivatives showed sustained release for 2-4 weeks and demonstrated prolonged biological activity of the released proteins in animals.  相似文献   
998.
We compared our heat pretreatment method to the widely used formic acid pretreatment technique to immunohistochemically detect amyloid in control and Alzheimer's disease brain tissues. Both methods detected amyloid in plaques, neurons, ependymal cells, circulating monocytes, vascular smooth muscle and endothelial cells. Although there were no observable differences in the intensity of the amyloid labeling in these cell types using both pretreatment methods, there were considerable differences in the intensity of amyloid immunolabeling in the plaques. The formic acid produced much more intense amyloid labeling in the plaques than the heat method. With the heat method, the intensity of the amyloid labeling in the plaques was similar to that detected in nearby neurons suggesting a neuronal origin of plaques. Conversely, the intensity of the amyloid in nearby neurons and plaques was drastically different using the formic acid suggesting unique origins of amyloid. The obvious benefits of formic acid for increasing the sensitivity of amyloid plaque immunolabeling may artifactually emphasize plaques over amyloid-containing cells during analyses.  相似文献   
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