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101.
Binge drinking is widespread on American college campuses, but its effects on the cardiovascular system are poorly understood. This study sought evidence of preclinical cardiovascular changes in binge drinking young adults (n = 24) compared to nondrinking (n = 24) and social drinking (n = 23) peers during baseline, paced sighing (0.033 Hz), and paced breathing (0.1 Hz) tasks. Binge drinkers showed consistent but often statistically nonsignificant evidence of greater sympathetic activation and reduced baroreflex sensitivity. Interestingly, the structure of group‐averaged baseline heart rate spectra was considerably different between groups in the low frequency range (0.05–0.15 Hz). In particular, the binge drinking group–averaged spectra showed several spectral peaks not evident in the other groups, possibly indicating two functionally distinct subranges (0.05–0.08 and 0.08–0.15 Hz) that reflect vascular tone baroreflex activity and heart rate baroreflex activity, respectively. Vascular tone baroreflex gain and power in two peaks in the 0.05–0.08 Hz range were associated with years of drinking in the binge drinking group. Vascular dysfunction may be an early indicator of drinking‐related change in the cardiovascular system.  相似文献   
102.
The implementation of digital radiography in dentistry in a large healthcare enterprise setting is discussed. A distinct need for a dedicated dental picture archiving and communication systems (PACS) exists for seamless integration of different vendor products across the system. Complex issues are contended with as each clinical department migrated to a digital environment with unique needs and workflow patterns. The University of Florida has had a dental PACS installed over 2 years ago. This paper describes the process of conversion from film-based imaging from the planning stages through clinical implementation. Dentistry poses many unique challenges as it strives to achieve better integration with systems primarily designed for imaging; however, the technical requirements for high-resolution image capture in dentistry far exceed those in medicine, as most routine dental diagnostic tasks are challenging. The significance of specification, evaluation, vendor selection, installation, trial runs, training, and phased clinical implementation is emphasized.  相似文献   
103.
This study examines EEG low frequency characteristics which have been linked to specific cognitive functions such as stimulus encoding and attention during an auditory oddball task in schizophrenia patients and healthy controls. EEG data was recorded from 17 young schizophrenia patients in a stable phase of their illness and 17 healthy controls performing an auditory oddball task. Evoked and induced delta and theta activity, N100, P300 amplitude were computed. Between 200–500 ms after a stimulus was presented, patients displayed significantly reduced P300, less evoked and induced delta and theta activity than controls. We conclude that the well known finding of P300 reduction in schizophrenia can be linked to reductions in delta and theta activity, which are a manifestation of impaired stimulus evaluation, memory retrieval, and a lack of sustained attention.  相似文献   
104.
Human facial attractiveness and facial sexual dimorphism (masculinity–femininity) are important facets of mate choice and are hypothesized to honestly advertise genetic quality. However, it is unclear whether genes influencing facial attractiveness and masculinity–femininity have similar, opposing, or independent effects across sex, and the heritability of these phenotypes is poorly characterized. To investigate these issues, we assessed facial attractiveness and facial masculinity–femininity in the largest genetically informative sample (n = 1,580 same- and opposite-sex twin pairs and siblings) to assess these questions to date. The heritability was ~0.50–0.70 for attractiveness and ~0.40–0.50 for facial masculinity–femininity, indicating that, despite ostensible selection on genes influencing these traits, substantial genetic variation persists in both. Importantly, we found evidence for intralocus sexual conflict, whereby alleles that increase masculinity in males have the same effect in females. Additionally, genetic influences on attractiveness were shared across the sexes, suggesting that attractive fathers tend to have attractive daughters and attractive mothers tend to have attractive sons.  相似文献   
105.
OBJECTIVE: To test the hypothesis that desmopressin facilitates acquisition of continence, we aimed to establish whether, in children with nocturnal enuresis who are desmopressin nonresponders, adjunct desmopressin increases the rate of sustained continence after treatment with a conditioning alarm.Study design Patients with nocturnal enuresis (n=358; age range, 6-16 years) completed a 4-week "run-in" course of intranasal desmopressin (20-40 microg). Of these, 207 defined as nonresponders (<50% reduction in wet nights) were randomly assigned to receive either desmopressin (n=101) or placebo (n=106) nasal spray, together with conditioning alarm therapy for 8 weeks. Principal outcome measures were remission (28 continuous dry nights) and relapse (>2 wet nights in 2 weeks after having achieved remission). RESULTS: Remission rates were similar in both groups (51.5% desmopressin, 48.1% placebo; 95% CI on difference, -10%, 17%; P=.63), and relapse rates were not significantly different (13.5% vs 5.9%; 95% CI on difference, -3.7%, 19%; P=.19). Although remission rates were similar, children treated with desmopressin had significantly more dry nights during treatment than those in the placebo group. CONCLUSIONS: Desmopressin did not act synergistically with alarm treatment to achieve remission. Therefore, we infer that in partial or nonresponders, desmopressin does not enhance learning.  相似文献   
106.
BACKGROUND: Non-contrast thin-section helical CT has gained acceptance for the diagnosis of urinary tract calculi in adults, but experience with the technique in children is limited. PURPOSE: To evaluate the utility of non-contrast thin section helical CT for the diagnosis of urinary tract calculi in children. MATERIALS AND METHODS: Radiology databases at three pediatric institutions were searched to identify all pediatric patients evaluated by "renal stone" protocol CT scans (no oral or intravenous contrast, scans covering the entire urinary tract obtained in helical mode with narrow collimation (< 5 mm)). CT scans were reviewed for the primary finding of urinary tract calculi, for secondary signs of acute urinary tract obstruction and for evidence of alternative diagnoses. Medical records were reviewed to determine clinical presentation and to confirm the eventual diagnosis. RESULTS: One hundred thirty-seven scans of 113 children (mean age: 11.2 years) were studied. Thirty-eight of 94 examinations (40%) performed on 82 children for acute pain and/or hematuria showed ureteral calculi. Alternative diagnoses were suggested by CT on 16 scans (17%). Twenty-eight scans were performed on 10 asymptomatic children with known calculus disease confirming renal stone burden on 21 scans (75%) and persistent ureteral calculi on 6 scans (21%). Upper tract calculi were demonstrated on 10 of 15 scans (67%) performed to evaluate for calculi in patients with known non-calculus genitourinary tract abnormalities. CONCLUSIONS: Non-contrast thin section helical CT is a useful method to diagnose urinary tract calculi in children. Radiation dose in this retrospective study may exceed the lowest possible radiation dose for diagnostic accuracy. Further research is needed to optimize CT imaging parameters, while maintaining diagnostic accuracy and minimizing radiation dose.  相似文献   
107.
Many children in Cape Town are co-infected with human immunodeficiency virus (HIV) and tuberculosis (TB). Granulomatous TB interstitial nephritis is a recognized entity. Our objective was to establish if TB plays a role in renal disease in HIV-infected children. We identified children co-infected with TB and HIV from our database and reviewed their biopsies and clinical notes. Since 2002, 12 renal biopsies or postmortem examinations were performed on HIV-infected children at our institution. The clinical scenario and renal biopsies in four cases (median age 73 months, range 24–108 months) were consistent with TB involvement. The mean CD4 count and percentage of these four patients were 508 cells/μl and 23%, respectively. All four patients presented with culture-proven disseminated TB (not yet on treatment) and had nephrotic range proteinuria and hypoalbuminemia. Three of these patients had renal impairment. The prominent features of the renal biopsies were a severe interstitial inflammatory infiltrate and mild to moderate mesangial proliferation. An interstitial granuloma was seen in one patient. With treatment for the TB, the proteinuria resolved and renal function improved in all four patients. Based on these results, we conclude that TB contributes to proteinuric renal disease in HIV-infected children and that the renal disease improves following TB treatment.  相似文献   
108.
Kaposi's sarcoma-associated herpesvirus (KSHV or HHV-8) has been associated with several neoplasias, including childhood endemic Kaposi's sarcoma (KS). It is possible that strain genotypes could contribute to the differences in regional presentation (mainly sub-Saharan Africa), childhood infection, lack of male sex bias, distinct disseminated forms and rapid fatality observed for childhood endemic KS. Early studies, at the advent of the HIV/AIDS epidemic, identified only the K1-A5 genotype in childhood KS biopsies as well as blood of a few HIV positive and negative febrile infants in Zambia, a highly endemic region. This current enlarged study analyses blood infections of 200 hospitalized infants (6-34 months age) with symptoms of fever as well as upper respiratory tract infection, diarrhoea, rash or rhinitis. KSHV and HIV viraemia and were prevalent in this group, 22% and 39%, respectively. Multiple markers at both variable ends of the genome (K1, K12, and K14.1/K15) were examined, showing diverse previously adult-linked genotypes (K1 A2, A5, B, C3, D, with K12 B1 and B2 plus K14.1/K15 P or M) detected in both HIV positive and negative infants, demonstrating little restriction on KSHV genotypes for infant/childhood transmission in a childhood endemic KS endemic region. This supports the interpretation that the acquisition of childhood KSHV infections and subsequent development of KS are due to additional co-factors.  相似文献   
109.
The quasistatic and dynamic pressure volume characteristics of the lungs were measured in five anesthetized, paralyzed open-chest rats. Psuedo-random volume perturbations over a frequency range of 0.25 to 25 Hz and having peak-peak amplitudes of 1 to 4 ml were applied after the lungs were allowed to expire against 0.2, 0.4, 0.6, and 0.8 kPa positive endexpiratory pressure (PEEP). The lung mechanics were partitioned in two ways: a linear dynamic block followed by a static nonlinearity (Wiener model) and a static nonlinearity ahead of a linear dynamic block (Hammerstein model). It was found that a Hammerstein model featuring a third-order polynomial static nonlinearity and a linear impulse response function of 1-sec duration accounted for the greatest amount of the output variance (98.8±06%, mean±SD from perturbations of 4 ml amplitude and PEEP-0.8 kPa). The static nonlinear behavior matched the measured quasistantic pressure volume behavior obtained at the same amplitude and at the same level of PEEP, provided that all direct current gain of the model was located within the static nonlinearity. Under these conditions, the linear resistance was inversely dependent on the PEEP, whereas little PEEP or amplitude dependence of the linear compartment elastance was observed. Thus, of the two block-structured models tested, the Hammerstein model accounted better for the large amplitude nonlinear mechanical behavior. However, neither model could account for the dependence of the linear block resistance on PEEP.  相似文献   
110.
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