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61.
62.
BACKGROUND AND PURPOSE: Our purpose was to describe the association between narrowing of the internal carotid artery (ICA) and retropharyngeal abscess in children. METHODS: Neck CT scans from 13 consecutive children with suppurative retropharyngeal lymphadenitis and abscess were evaluated retrospectively for asymmetric ICA diameters at the level of the abscess. Clinical status at the time of illness was established via a chart review. Twenty control CT scans obtained from pediatric patients with normal imaging findings were evaluated prospectively to determine symmetry and size of the ICA. RESULTS: Mean diameter of the normal ICA, contralateral to the retropharyngeal abscess, was 5 mm (range, 3-8 mm), while mean diameter ipsilateral to the abscess was 3 mm (range, 1-5 mm). The diameters of the normal and abnormal ICAs were statistically significantly different. All children were neurologically normal. The right and left ICAs in children with normal CT findings in the neck were symmetrical in diameter. CONCLUSION: Despite dramatic narrowing of the ICA ipsilateral to retropharyngeal lymphadenitis and abscess, no children in this series had neurologic deficits, suggesting that such narrowing is a common, benign, and, most likely, incidental imaging finding. 相似文献
63.
64.
The purpose of this study was to determine how well men recall reproductive information. By using a questionnaire, the authors surveyed men who had undergone orchiopexy for undescended testes and a group of matched control men, all of whom had had surgery at the Children's Hospital of Pittsburgh in Pittsburgh, Pennsylvania (n = 77), and their spouses. Subjects were a random subset of a larger (n = 1,212) male fertility study, which has been ongoing since 1992. In 1994, the spouses of men who participated in the study completed a short telephone survey that contained questions previously asked of their partners. Pearson correlations and kappa statistics were calculated to evaluate the accuracy of male recall of reproductive information. For the continuous measures, such as time to conception and frequency of intercourse, the correlations were high to moderate (r = 0.84 (p < 0.001) and r = 0.45 (p < 0.001), respectively). Agreement between the men and their spouses on the majority of bivariate (yes/no) questions, such as those concerning the use of birth control, as measured by the kappa statistic, was moderate to very good (K ranged from 0.14 to 0.69). Statistics were similar for formerly cryptorchid and control men. Male participants' responses to questions about their reproductive histories were accurate as compared with the responses given by their spouses. In this sample from a large cohort study, men appeared to recall reproductive information with acceptable accuracy. 相似文献
65.
During ventilatory acclimatization to hypoxia (VAH), the relationship between ventilation (VE) and end-tidal PCO2 (PETCO2) changes. This study was designed to determine 1) whether these changes can be seen early in VAH and 2) if these changes are present, whether the responses differ between isocapnic and poikilocapnic exposures. Ten healthy volunteers were studied by using three 8-h exposures: 1) isocapnic hypoxia (IH), end-tidal PO2 (PETO2) = 55 Torr and PETCO2 held at the subject's normal prehypoxic value; 2) poikilocapnic hypoxia (PH), PETO2 = 55 Torr; and 3) control (C), air breathing. The VE-PETCO2 relationship was determined in hyperoxia (PETO2 = 200 Torr) before and after the exposures. We found a significant increase in the slopes of VE-PETCO2 relationship after both hypoxic exposures compared with control (IH vs. C, P < 0.01; PH vs. C, P < 0.001; analysis of covariance with pairwise comparisons). This increase was not significantly different between protocols IH and PH. No significant changes in the intercept were detected. We conclude that 8 h of hypoxia, whether isocapnic or poikilocapnic, increases the sensitivity of the hyperoxic chemoreflex response to CO2. 相似文献
66.
A microstructural analysis of licking behavior in nondeprived and 23-hr food-deprived rats (n = 15) presented with various sucrose solutions (0.03-1.0 M) in daily single-bottle, 1-hr sessions was conducted. Food deprivation and concentration interacted to increase total licks. The effects of food deprivation and concentration on burst size (BS), burst number (BN), and other parameters varied as a function of the pause criterion (PC; 0.3-100 s) used to define licking bursts. A rationale for selecting a 1-s PC for further analysis is presented. Despite the lack of correlations between temporally contiguous burst and pause combinations, mean BS decreased and pause duration increased as meals progressed. At the 1-s PC, BS increased linearly with concentration, implying that this microstructural parameter is influenced in part by taste. Food deprivation did not affect BS but rather increased BN and proportionally extended the meal duration. 相似文献
67.
The Surveillance Research Program of the American Cancer Society's Department of Epidemiology and Surveillance reports its 32nd annual compilation of cancer incidence, mortality, and survival data for the United States and around the world. 相似文献
68.
Y Huang CA Macera SN Blair PA Brill HW Kohl JJ Kronenfeld 《Canadian Metallurgical Quarterly》1998,30(9):1430-1435
PURPOSE: A cohort of middle-aged and older men and women were followed for an average of 5.5 yr to examine the association between physical fitness, physical activity, and the prevalence of functional limitation. METHODS: The participants received medical assessments between 1980 and 1988 and responded to a mail-back survey regarding functional status in 1990. RESULTS: Among 3495 men and 1175 women over 40 yr of age at baseline, 350 (7.5%) reported at least one functional limitation in daily or household activities at follow-up. The prevalence of functional limitation was higher among women than men. Physically fit and physically active participants reported less functional limitation than unfit or sedentary participants. After controlling for age and other risk factors, the prevalence of functional limitation was lower for both moderately fit (odds ratio = 0.4, 95% CI = 0.2-0.6) and high fit men (odds ratio = 0.3, 95% CI = 0.2-0.4), compared with low fit men. Corresponding figures for women were 0.5 (0.3-0.7) and 0.3 (0.2-0.5) for moderately fit and high fit women. The association between physical activity and functional limitation was similar to the data for physical fitness. CONCLUSIONS: These data support a protective effect of physical fitness and physical activity on functional limitation among older adults and extend this protective effect to middle-aged men and women. 相似文献
69.
We have isolated an insertional mutant of Dictyostelium discoideum that aggregated rapidly and formed spores and stalk cells within 14 h of development instead of the normal 24 h. We have shown by parasexual genetics that the insertion is in the rdeA locus and have cloned the gene. It encodes a predicted 28 kDa protein (RdeA) that is enriched in charged residues and is very hydrophilic. Constructs with the DNA for the c-Myc epitope or for the green fluorescent protein indicate that RdeA is not compartmentalized. RdeA displays homology around a histidine residue at amino acid 65 with members of the H2 module family of phosphotransferases that participate in multistep phosphoryl relays. Replacement of this histidine rendered the protein inactive. The mutant is complemented by transformation with the Ypd1 gene of Saccharomyces cerevisiae, itself an H2 module protein. We propose that RdeA is part of a multistep phosphorelay system that modulates the rate of development. 相似文献
70.
To assess the completeness of human immunodeficiency virus (HIV) reporting among hospital inpatients whose records listed diagnostic codes for HIV infection but who did not meet the 1987 AIDS case definition, we conducted a statewide hospital study of admissions between January 1, 1986 and December 31, 1990. Of the 396 HIV-infected hospital inpatients identified, 313 (79%) had been reported to the State HIV Registry. HIV reporting was less complete for patients who were older and/or were blood product recipients. Of the 313 reported patients, 189 (60%) had been reported prior to their first hospital admission. Temporal improvements were noted in the completeness of HIV reporting among the hospital patients (1986: 65%; 1987: 81%; 1988: 64%; 1989: 82%; 1990: 86%; Chi square for linear trend 9.6, p < 0.01) and prior to their first hospital admission (1986: 31%; 1987: 34%; 1988: 49%; 1989: 64%; 1990: 72%; Chi square for linear trend 26.6; p < 0.01). Women were more likely than men to be reported prior rather than during or after their first hospital admission (71% vs. 55%; p < 0.01). Of the 155 patients with CD4+ T-lymphocyte test results, 41 had CD4+ counts < 200 mm3 and met the 1993 but not the 1987 AIDS case definition. In South Carolina most (79%) diagnosed, hospitalized, HIV-infected patients had been reported to the State HIV REgistry, with improvements in reporting occurring over time. Findings suggest that the 1993 AIDS case definition will improve our ability to monitor severe morbidity related to HIV. 相似文献