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Dietary intake during diarrhea in children less than three years of age was estimated from information recorded on illustrated dietary forms used by children's caretakers during the first week of illness in a prospective community-based study of diarrheal diseases in Lima, Peru. The frequency of consumption and the amount consumed of food groups and selected commonly consumed foods were analyzed by the final duration of the diarrheal episode. Cereals were less frequently consumed during the acute phase of diarrheal episodes that ultimately became persistent (>14 days'duration), apparently shortening the duration of the episode by one day (median duration of four days in children not consuming vs three days in children consuming cereals during diarrhea, p <0.02 Kaplan-Meier logrank test). Only roots and tubers (mainly potatoes) were consumed in greater quantity during episodes that became persistent. There was no evidence that consumption of breast milk or non-maternal milk was associated with an alteration in diarrheal duration. This study provides further evidence of the beneficial effects of continuing feeding during diarrhea using foods available at the home level, especially cereals, which are commonly used in the diet of young children.  相似文献   
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During a 12-month surveillance period in 1981-1982, Moraxella catarrhalis was detected in cultures from nasopharyngeal aspirates from 76 (17%) of 449 children hospitalized with middle or lower respiratory tract infection. Seroconversion to M. catarrhalis was positive in 4(5%) of the 76 patients with M. catarrhalis present in nasopharyngeal aspirates and in 4(1%) of 373 patients with a negative finding. Although children with respiratory tract infections were often colonized by the organism, this was rarely the infective agent of the middle or lower airways. Four of 8 patients with seroconversion to M. catarrhalis exhibited a concomitant RSV infection. The carriage of this species was more closely associated with parainfluenza virus infections. Serological responses to M. catarrhalis were not associated with acute otitis media, and were also rare in children with pneumonia. It is concluded that bronchopulmonary infections caused by M. catarrhalis are rare in children, and that M. catarrhalis aetiology need not be considered in the selection of antibiotics in cases of community-acquired pneumonia or other infections of the middle or lower respiratory tract affecting primarily healthy children.  相似文献   
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A study of tuberculin sensitivity was performed in 353 children aged 4-6 years, all vaccinated at birth with British BCG vaccine. Significant waning of tuberculin reactions with increasing age was found (p < 0.05). In the age group < 4.5 years, the mean tuberculin reaction was 6.6 mm, in the age group 4.5-5.5 years 5.2 mm and in the age group of > 5.5 years 3.5 mm. The number of children with positive reactions (> or = 5 mm) was 165 (40%) and those with strong reactions (> or = 10 mm) 49 (14%). None of the latter children had active tuberculosis during a follow-up period of 12 months. Eighty-three (24%) of the children had no reaction. The children who had been revaccinated with the MPR vaccine against measles, rubella and parotitis (n = 31) had significantly larger tuberculin reactions than the non-revaccinated children. Atopic dermatitis or infections during the preceding six months did not have any significant influence on reaction sizes. Our results demonstrate that the variation in size of tuberculin reactions after BCG vaccination at birth is large. We conclude that tuberculin sensitivity wanes rapidly by the age of 4.0-6.3 years.  相似文献   
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Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children.  相似文献   
17.
Bissonette EA  Fulmer BR  Petroni GR  Moul JW  Theodorescu D 《The Journal of urology》2001,166(4):1328-31; discussion 1331-2
PURPOSE: It has been shown that black men with clinically localized prostate adenocarcinoma treated with radical prostatectomy have poorer disease-free and disease specific survival than white men with similar tumors. These findings suggest that a potentially more aggressive variant of prostate cancer exists in black men. Because prostate specific antigen (PSA) velocity at tumor recurrence is a good indicator of disease aggressiveness, we determine whether there was evidence that PSA velocity at biochemical recurrence after radical prostatectomy is faster in black men. MATERIALS AND METHODS: Our retrospective data search at 2 university centers resulted in 127 white and 37 black men with clinical stage cT1 to 2 prostate adenocarcinoma who underwent radical prostatectomy between 1990 and 1994 and had evidence of biochemical recurrence (PSA greater than 0.2 ng./ml.) on followup available for analysis. No neoadjuvant or adjuvant treatments were given before or after radical prostatectomy, and all PSA relapses and subsequent treatments were recorded. PSA velocity modeling was performed in patients before any form of treatment for PSA failure. Preoperative PSA, Gleason score and pathological stage were also included in the model to assess the impact on PSA velocity after recurrence. RESULTS: Our data suggested that PSA velocity at tumor recurrence was related to preoperative PSA on a continuous scale (p = 0.063). However, in our analysis there was little evidence that race had any effect on PSA velocity at tumor recurrence in our patient cohort (p = 0.58). Likewise, little difference in PSA velocity was seen in regard to Gleason score (p = 0.89) or pathological stage (p = 0.23) in these patients. With data on 37 black men available for analysis it was likely that only large or extreme trends could be detected. Results could be used to estimate required sample sizes for assessment of less extreme trends. CONCLUSIONS: Our data on tumor growth rate at recurrence, as reflected by PSA velocity kinetics, do not support the hypothesis that prostate tumors in black men are necessarily more aggressive due to enhanced growth. Further studies comparing the molecular and biological differences between prostate cancers in black and white males are needed to clarify reasons for the apparent differences in initial presentation, as compared to that at tumor recurrence in these 2 groups.  相似文献   
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Natural and human-caused disasters, violence with weapons, and terrorist acts have touched directly the lives of thousands of families with children in the United States.1 Media coverage of disasters has brought images of floods, hurricanes, and airplane crashes into the living rooms of most American families, with limited censorship for vulnerable young children. Therefore, children may be exposed to disastrous events in ways that previous generations never or rarely experienced. Pediatricians should serve as important resources to the community in preparing for disasters, as well as acting in its behalf during and after such events.  相似文献   
20.
The pattern of anatomical connections between areas of the primate visual system is organized hierarchically. However, onset latencies in parietal and occipital stations are often simultaneous, and this seems to contradict hierarchical organization in its simplest interpretation, as serial organization. To understand the reasons for this contradiction, we simulated the cortical network for which there is onset data, including the network's hierarchical structure. The network's dynamics reproduced the simultaneous onset latencies reported in several dorsal areas. These results show that a strictly hierarchical visual system is compatible with much more complex dynamics than serial processing, and that hodological and biophysical properties, are more closely related to onset dynamics than is hierarchical organisation.  相似文献   
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