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51.
The aims of this study were to determine the risk factors in, and the clinical and laboratory characterizations of, Shigella bacteremia, as well as the subspecies of Shigella, and the antibiotic susceptibility. A retrospective study of all patients younger than 18 years of age with documented Shigella bacteremia from January 1989 through December 2001 was conducted. Fifteen children with Shigella bacteremia were treated at our center. The mean age (+/- SD) was 20.5 months (+/- 34.2), median 7 months. Thirteen (87%) patients failed to gain weight. The mean duration of diarrhea was 14.7 days. Patients were hospitalized for a mean (+/- SD) of 13.5 days (+/- 9.2). There were no fatalities in our study sample. The vast majority (86.7%) of the Shigella isolates were flexneri. Most isolates were susceptible to ceftriaxone, ciprofloxacine, and gentamicin but resistant to ampicillin and trimethoprim/sulfamethoxazole.  相似文献   
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The Caenorhabditis elegans hermaphrodite nervous system is composed of 302 neurons that fall into at least 118 diverse classes. Here we describe cfi-1, a gene that contributes to the development of neuronal diversity. cfi-1 promotes appropriate differentiation of the URA sensory neurons and inhibits URA from expressing the male-specific CEM neuronal fate. The UNC-86 POU homeodomain protein is present in CEM and URA neurons, and can promote expression of CEM-specific genes in both CEM and URA, but CFI-1 inhibits expression of these genes in the URA cells. cfi-1 also promotes appropriate differentiation and glutamate receptor expression in the AVD and PVC interneurons. cfi-1 encodes a conserved neuron- and muscle-restricted DNA-binding protein containing an A/T rich interaction domain (ARID). ARID proteins regulate early patterning and muscle fate in Drosophila, but they have not previously been implicated in the control of neuronal subtype identity.  相似文献   
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BACKGROUND: With improved socioeconomic conditions, adults are more frequently seronegative for hepatitis A virus (HAV) and therefore susceptible to infection. A safe and efficacious active HAV vaccine has been developed and licensed. The general recommendation is to vaccinate populations at increased occupational exposure to HAV. AIM: To determine the seroprevalence of HAV antibodies among children's hospital employees and to correlate seropositivity with demographic and occupational variables as a basis for formulating vaccine recommendations. METHODS: The staff of a tertiary pediatric medical center participated by answering a structured questionnaire on demographic and occupational data and by donating venous blood for determining HAV antibodies by an enzyme immunoassay. Univariate and multivariate analyses were conducted to identify variables associated with HAV seropositivity. RESULTS: HAV antibodies were found in 48.3% of the 499 employees studied, being lowest in pediatricians (38.7%), and increased with years of work at the hospital, job percentage and contact with pediatric patients. However, multivariate analysis showed that only the sociodemographic variables (age and crowding during childhood) were independently and significantly associated with seropositivity. CONCLUSIONS: HAV seropositivity was associated mainly with sociodemographic variables. Most children's hospital employees, especially pediatricians and other young (<40 years) employees, are seronegative and therefore susceptible to HAV. Vaccination of the high risk groups should be considered.  相似文献   
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OBJECTIVE: The purpose of this study was to determine the accuracy of CT angiography using a multidetector scanner in the evaluation of patients with peripheral vascular disease. SUBJECTS AND METHODS: Eighteen patients with peripheral vascular disease who were referred for elective digital subtraction angiography (DSA) also underwent CT angiography. We scanned patients from the level of the superior mesenteric artery to the pedal arteries in a single helical scan. CT angiograms were produced using maximum-intensity-projection reconstructions. Findings were graded according to six categories: 1, normal (0% stenosis); 2, mild (1-49% stenosis); 3, moderate (50-74% stenosis); 4, severe (75-99% stenosis); 5, occluded; and 6, nondiagnostic. CT angiography findings were compared with DSA findings for each arterial segment. RESULTS: We found agreement for the degree of stenosis in 77.7% of the arteries and discrepancy for 22.3% of the arteries when all categories were considered. Grouping the six categories according to the threshold for treatment (categories 1 and 2 as one group and categories 3, 4, and 5 as the second group) resulted in an agreement of 91.95%. Compared with DSA, CT angiography yielded a sensitivity of 90.9% and a specificity of 92.4%. CONCLUSION: Multidetector CT angiography is an accurate, noninvasive technique for the imaging of peripheral vascular disease.  相似文献   
55.
OBJECTIVE: To determine dietary intake and eating patterns of older persons in Israel and to identify factors associated with low intake. DESIGN: A cross-sectional study. SETTING: Community-dwelling participants living in the Beer-Sheva area were interviewed at home, using a 24 h food questionnaire with additional questions regarding health and eating habits. Dietary intake was compared between people aged 65-74 and 75 y and older. SUBJECTS: A total of 377 people over the age of 65 224 aged 65-74 and 153>75, were randomly selected from the Negev population. RESULTS: Dietary intake of energy, fat, carbohydrates, vitamins E, C and B(1) were significantly lower for people aged 75 and older compared with people aged 65-74. Low energy intake was associated with lower subjective health status for men (P<0.01), poor appetite (P<0.01) and more gastrointestinal problems (P<0.05) for women and lower snack consumption (P<0.01) for both genders. In a multivariate model, low energy intake was associated with low appetite and higher use of medication for both sexes and with frequency of eating alone and not consuming snacks for men. CONCLUSIONS: Dietary intake is lower among individuals older than 75 than in 65-74 y old. Risk factors for low intake include poor appetite and health status, gastrointestinal problems, and eating alone. Snacking enhanced dietary intake and should be encouraged in this group.  相似文献   
56.
A telecare system (Medic4All) has been developed that relies on a wireless wristwatch-like sensor to measure the pulse wave from the radial artery. From this, the heart rate and respiration rate are derived. The system's performance was examined by comparing the results obtained from the pulse wave signal with those obtained from conventional electrocardiographic and spirometer devices. A total of 144 patients participated in the study; their mean (SD) age was 43 (18) years. There were 44 cardiac patients in group 1 and 100 healthy patients, who were studied in their homes, in group 2. There was a significant correlation between the heart rates measured by the two monitoring methods. A 'difference versus average' analysis showed that the error distribution had a mean (SD) value of -0.1 (3.3) beats/min. Similarly, the respiration rates measured by the two techniques were significantly correlated. The error distribution had a mean (SD) value of 0.1 (1.9) respirations/min. The present study suggests that the wrist-worn sensor represents a promising tool for online detection and monitoring of vital signs in the home.  相似文献   
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Older people have different eating patterns than their younger counterparts, although in most nutritional studies of older populations, food frequency questionnaires (FFQ) that were developed and validated for the general adult population are used. In this paper, we present the advantages of developing an FFQ for an older population based on a population survey. A random sample of the Negev's (Southern Israel) Jewish population > or = 35 y old was recruited and interviewed for their dietary intake using 24-h recalls. Foods eaten were aggregated into conceptually similar groups and entered into stepwise regression models to predict variation in nutrient intake. We interviewed 796 people age 35-64 y and 377 people > or = 65 y old for the study. Significantly more items were required to reach 80% between-person variability for zinc, magnesium, vitamin E and protein for the elderly compared with the younger age group. Portion sizes of most items consumed by the elderly were smaller compared with the Israeli Ministry of Health portion sizes booklet and the younger age group's intake estimates. The nutrient values assigned for each line based on a weighted mean of the intake of the elderly were different from those using the most frequently used item. The above findings highlight some of the advantages of developing an FFQ for an older population based on a population survey. Further studies are required to compare the validity of existing tools adapted for the elderly to those developed on the basis of population surveys.  相似文献   
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