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71.
In adults, both active and passive smoking reduce levels of exhaled nitric oxide (eNO); however, to date, passive exposure to environmental tobacco smoke (ETS) has not been shown to affect eNO in children. The authors recruited 174 asthmatic children (96 male, 78 female) and 79 nonasthmatic controls (46 male, 33 female) from a group of children aged 5 to 14 yr who attended a children's hospital for an outpatient visit or elective surgery. Each subject's exposure to ETS was ascertained by questionnaire, and their eNO levels were measured. Asthmatic children had higher eNO levels (ppb) than nonasthmatic children (p = 0.04), and asthmatic children exposed to ETS had significantly lower eNO levels than unexposed children (p = 0.005). Exposure to ETS did not alter eNO levels in nonasthmatic children (p = 0.4). Results of the study suggest that ETS exposure is associated with lower eNO levels among childhood asthmatics. Consequently, ETS exposure may need to be considered when physicians interpret eNO levels in asthmatic children. Further study of the effects of ETS on eNO levels is recommended. 相似文献
72.
Peiffer AM Dunleavy CK Frenkel M Gabel LA LoTurco JJ Rosen GD Fitch RH 《Neuroreport》2001,12(13):2875-2879
Utilizing rodent models, prior research has demonstrated a significant association between focal neocortical malformations (i.e. induced microgyria, molecular layer ectopias), which are histologically similar to those observed in human dyslexic brains, and rate-specific auditory processing deficits as seen in language impaired populations. In the current study, we found that ectopic NZB/BINJ mice exhibit significant impairments in detecting a variable duration 5.6 kHz tone embedded in a 10.5 kHz continuous background, using both acoustic reflex modification and auditory event-related potentials (AERP). The current results add further support to the association between focal cortical malformations and impaired auditory processing, and the notion that these auditory effects may occur regardless of the cortical location of the anomaly. 相似文献
73.
Gray RE Carroll J Goel Orr Fitch M Chart P Fleshner N Morris BA Greenberg M 《The Canadian journal of urology》1999,6(6):892-897
A sample of family physicians was randomly selected from the membership database of the College of Family Physicians of Canada (CFPC). Potential respondents were mailed a survey questionnaire, and a modified Dillman approach was utilized. A total of 964 completed questionnaires were received, providing a response rate of 50.1%. Although most family physicians were aware of many basic facts about prostate cancer, there were knowledge limitations related to risk factors, relative frequency of the disease (to other cancers), and selected aspects of PSA effectiveness. There was considerable variation in perceived effectiveness of early detection methods, with most physicians taking a conservative approach to PSA utilization. Most family physicians indicated that they have an important role to play in the care of men after they have been diagnosed with prostate cancer. They also expressed a high level of interest in obtaining additional information related to prostate cancer. 相似文献
74.
Jesse R. Cougle Christine Purdon Kristin E. Fitch Kirsten A. Hawkins 《Cognitive therapy and research》2013,37(2):221-231
Conflicting findings regarding the relations between thought-action fusion (TAF), religiosity, and obsessive compulsive disorder (OCD) may be due to a lack of clarity regarding the intent associated with the negative thoughts under consideration. In Study 1, we examined the perceptions of the immorality of intentional and unwanted morally-relevant thoughts (Moral TAF) and their relations with OCD symptoms, religiosity, and obsessive beliefs in a non-clinical sample. In Study 2, we randomly assigned participants to complete one of two versions of a previously used sentence neutralization task that was varied in terms of intent. Perception of the immorality of intentional negative thoughts but not unwanted negative thoughts was associated with Protestant/Catholic affiliation and greater prayer frequency, and perception of the immorality of unwanted thoughts was consistently associated with obsessive beliefs. Neither form of Moral TAF was associated with OCD symptoms. Further, reaction to the modified non-intentional neutralization task was associated with OCD symptoms, thought-action fusion, and scrupulosity, while reaction to the original intentional task was only associated with Moral TAF. Overall, the findings suggest that individuals differ in their perceptions of intentional versus unintentional thoughts. Perceptions of intentional morally-relevant thoughts appear related to religiosity, while perceptions of unintentional thoughts are likely to be of greater relevance to our understanding of OCD. 相似文献
75.
Magill HL; Clarke EA; Fitch SJ; Boulden TF; Ramirez R; Siegle RL; Somes GW 《Radiology》1986,161(3):625-630
A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent. 相似文献
76.
The Program on the Surgical Control of Hyperlipidemias (POSCH) is a multicentered, randomized, secondary intervention trial assessing the effect of lipoprotein modification achieved by partial ileal bypass (PIB) on overall mortality rates and the course of coronary heart disease. Of the 838 participants, 396 (196 control and 200 surgical patients) have complete 5-year lipoprotein results and are the basis of this report. After PIB, total cholesterol level decreased 24 +/- 1.2% (mean +/- SEM) and low-density lipoprotein cholesterol level fell 38 +/- 1.5% in comparison with control subjects. High-density lipoprotein (HDL) cholesterol level was not changed by PIB; however, a significant decrease in HDL occurred over 5 years in the control group (41.7 +/- 0.7 mg/dl versus 39.5 +/- 0.6 mg/dl, p less than 0.05). This led to consistently higher HDL levels in the surgical group in comparison with control subjects after PIB. Very low-density lipoprotein cholesterol and triglyceride levels were higher in the surgery group than in control subjects (24 +/- 7.6% and 21 +/- 5.4% at 5 years). Apolipoprotein B-100 was significantly lower, and apolipoprotein A-I and HDL-2 were significantly higher in the surgery group. These lipoprotein changes are greater than have been reported from any previous trial of dietary or pharmacologic intervention, including the Lipid Research Clinics-Coronary Primary Prevention Trial, which used cholestyramine. Based on available epidemiologic data, these changes predict a marked reduction in morbidity and mortality rates associated with coronary heart disease after PIB. 相似文献
77.
Encouraged by the popularity of the pulse oximeter pulse-tone, we developed and tested an auditory display of six physiologic variables. The display consisted of a cardiovascular sound triggered by every heartbeat (conveying heart rate) and a respiratory sound triggered by every breath (conveying respiratory rate). Attributes of the cardiovascular sound were modulated to convey hemoglobin saturation and blood pressure, and those of the respiratory sound were modulated to denote end-tidal CO(2) and tidal volume. Three display formats (auditory, visual, and combined) were compared. Fourteen anesthesia residents monitored dynamic displays of 6 variables to detect and identify 6 predefined events during 21 trials. An event occurred during each trial and the subject's task was to detect when it started and then identify the type of event. Subjects detected every event. They detected events more rapidly with the combined display (10.4 s) than with the visual (12.8 s) or auditory (13.0 s) displays. Subjects correctly identified events least often with the auditory display (60% versus visual 88% and combined 80%). They correctly identified events more quickly with the combined display than with the visual display. We conclude that, with little training, clinicians can successfully detect and identify simulated clinical events using an auditory display of six variables. IMPLICATIONS: We developed and tested an auditory display of multivariable clinical data. With little training, clinicians successfully used the display to detect and diagnose simulated critical events. This suggests that a multivariable auditory display could enhance intraoperative monitoring. 相似文献
78.
Consistency of fundamental frequency and perturbation in repeated phonations of sustained vowels, reading, and connected speech 总被引:1,自引:0,他引:1
J L Fitch 《The Journal of speech and hearing disorders》1990,55(2):360-363
The purpose of this study was to determine consistency of the acoustic measurement of fundamental frequency (f0) and f0 perturbation using the Visi-Pitch. Samples of speech including a reading passage, vowels, and spontaneous speech were recorded for 12 normal young adults (6 men and 6 women). The results indicated that test-retest reliability was highest for the reading passage. The measurements of fundamental frequency for reading and spontaneous speech were very similar, but vowel production was, on average, higher in frequency than the other contexts. Test-retest measures of perturbation using the Visi-Pitch did not have a high correlation coefficient. Perturbation measures must be interpreted cautiously because of the influence of frequency. 相似文献
79.
The endothelial cells of the C57BL/6J mouse cornea show a progressive age-related increase in cell area, and an increasing departure from the initial hexagonal form. Mean endothelial surface areas were 304, 386, 458, 499, and 653 micron2 for mice of ages 1, 4, 11, 22, and 27 months, respectively. Increasing cell areas are interpreted to represent a spreading and thinning of surviving cells to compensate for cell loss. These age-related changes correspond to those previously observed in the rat, although the rat endothelial cells tend to have smaller cell areas and show less variation at each age studied. 相似文献
80.
A case of invasive gastric candidiasis is reported. The frequency and importance ofCandida sp. as a gastric pathogen is reviewed. 相似文献