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The purpose of this study was to determine the normal characteristics of the lower extremity arterial system as seen with color Doppler. A total of 420 arterial segments from the level of the proximal abdominal aorta to the distal tibial and peroneal vessels were examined with a color ultrasound scanner in 10 normal volunteers. Each arterial segment was examined for the presence of triphasic flow, wall irregularities, calcification, bruits, collaterals, and post-stenotic flow patterns. Standard duplex spectral waveform data were also obtained at each site. As expected, triphasic flow was present and detected by color Doppler in the majority of arterial segments. Color patterns suggesting the presence of bruits, collaterals, or post-stenotic flow were absent in all cases.  相似文献   
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The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.  相似文献   
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Several past studies have reported reliable changes in reaction time performance and self-rated withdrawal scores as a consequence of cigarette deprivation. The purpose of the present study was to determine, prospectively, the effect 24 h of smokeless tobacco deprivation in regular users has on performance and the associated withdrawal symptomology. Forty smokeless tobacco users (Copenhagen brand) were randomly divided evenly into two groups gen brand) were randomly divided evenly into two groups (N=20)24 h of deprivation and no deprivation. A third group of ten nonchewers was added as another control group. The results indicated that behavioral, subjective and physiological changes are associated with smokeless tobacco deprivation in regular users. These include increased craving scores, reaction time, self-rated withdrawal symptoms and decreased heart rate.  相似文献   
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BACKGROUND: This study was undertaken to evaluate the long-term smoking cessation efficacy of varying doses of transdermal nicotine delivery systems 4 to 5 years post-quit day. METHODS: A follow-up study was conducted 48 to 62 months after quit day among patients who were enrolled in the Transdermal Nicotine Study Group investigation. The latter study included group smoking cessation counseling and randomized assignment to 21, 14, or 7 mg nicotine patches or placebo patches. Seven of nine smoking cessation research centers participated in the long term follow-up investigation. RESULTS: The self-reported continuous quit rate among patients originally assigned 21 mg (20.2%) was significantly higher than rates for patients assigned 14 mg (10.4%), 7 mg (11.8%), or placebo patches (7.4%). Log rank survival analysis found no difference in relapse rates after 1 year postcessation. Smokers under age 30 years were significantly less likely to be abstinent at long term follow-up compared to smokers > or = 30 years of age (3 vs 13%, respectively). Mean weight gain in confirmed continuous quitters was 10.1 kg in men and 8.0 kg in women. Of the 63 continuous abstainers surveyed, 30 respondents (48%) reported that they no longer craved cigarettes, and no individual reported daily craving for cigarettes. CONCLUSIONS: Nicotine patch therapy with 21 mg/day patches resulted in a significantly higher long-term continuous abstinence rate compared to lower dose patches and placebo. Relapse rates among the various treatment conditions were similar after 1 year postcessation.  相似文献   
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Characteristics of patients with a diagnosis of bulimia only (N = 46), bulimia with a history of affective disorder (N = 34), and bulimia with a history of substance abuse (N = 34) were compared. Results showed that compared to patients with bulimia only or with bulimia and affective disorders, patients with bulimia and substance abuse experienced a higher rate of diuretic use to control weight, financial and work problems, stealing before and after the onset of the eating disorder, previous psychiatric inpatient treatment, and greater amount of alcohol use after the onset of the eating disorder. Both the substance abuse group and affective disorder group showed a higher incidence of attempted suicide, more social problems, and greater overall treatment rate than the bulimia only group. There were no significant differences among groups in their family histories.  相似文献   
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Background: Reducing the social acceptability of smoking is associated with lowered smoking prevalence. However, denormalization strategies can also contribute to the stigmatization that some smokers may feel about their smoking. Smoking stigma may be more acute if smokers are also members of other stigmatized groups, such as racial/ethnic minorities. This study examined correlates of smoking self- and felt-stigma and discrimination, among current smokers. Methods: Participants were recruited in the United States via a national commercial consumer panel to complete a cross-sectional, Web-based survey. Participants were 1528 current cigarette smokers aged 14 and older. Measures included the Internalized Stigma of Smoking Inventory (ISSI), Heaviness of Smoking Index, quit intentions, past-year quit attempts, and current use of electronic cigarettes (e-cigarettes). Results: Self-stigma was significantly associated with higher intent to quit in the next 6 months (odds ratio [OR] = 2.47, P < .01) and in the next 30 days (OR = 4.21, P < .01), relative to no intention to quit, as well as having made 1 or 2 quit attempts in the past year (OR = 1.60, P < .01) or 3 or more quit attempts (OR = 1.74, P < .01) and associated with daily e-cigarette use (OR = 1.73, P < .05). Felt-stigma was positively associated with intent to quit in the next 30 days (OR = 1.54, P < .01), having made 3 or more quit attempts in the past year (OR = 1.35, P < .01), and both daily (OR = 2.05, P < .05) and some-day (OR = 1.30, P < .05) e-cigarette use. Discrimination was associated only with increased odds of daily e-cigarette use (OR = 1.83, P < .05). Conclusions: Smokers who reported greater feelings of stigmatization about their smoking were more likely to report having made recent quit attempts, report a stronger intention quit smoking in the future, and report use of e-cigarettes, suggesting that feelings of self-and felt-stigmatization are related to greater motivation to stop smoking.  相似文献   
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PURPOSE: To determine whether sustained-release bupropion promotes smoking reduction leading to smoking cessation among persons who wish to reduce their amount of smoking, but who are unwilling to quit or who perceive themselves as being unable to quit. METHODS: Current smokers were assigned randomly to receive either sustained-release bupropion (150 mg twice daily) or matching placebo. During an initial 6-month smoking reduction phase, those who were willing to quit entered a 7-week cessation phase, during which study medication was continued. RESULTS: Four-week continuous abstinence rates were 14% (41/295) in the bupropion group and 8% (25/299) in the placebo group (P = 0.02) during treatment. However, this benefit did not continue after treatment was stopped; subsequent continuous abstinence rates were 7% (20/295) in the bupropion group and 5% (16/299) in the placebo group (P = 0.50). Similar proportions of subjects entered the cessation phase in both treatment groups (38% [n = 113] of those in the bupropion group and 34% [n = 101] of those in the placebo group), although the time until a cessation attempt was shorter for those taking bupropion (median, 64 days vs. 118 days, P = 0.008). The extent of smoking reduction (measured by urinary cotinine concentrations) among the 327 subjects who did not enter the cessation phase was significantly greater (P <0.05) in those treated with bupropion during the reduction treatment phase, but not during the month 12 follow-up visit (P = 0.25). CONCLUSION: Sustained-release bupropion, when used in smokers initially not willing to make a cessation attempt, can help sustain smoking reduction while subjects are on active medication, reduce the time until the next cessation attempt, and increase short-term abstinence rates. However, these benefits were modest and not sustained after bupropion was discontinued.  相似文献   
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Cerebral malaria is thought to involve specific attachment of Plasmodium falciparum-infected knobby red cells to venular endothelium. The nature of surface ligands on host endothelial cells that may mediate cytoadherence is poorly understood. We have investigated the effects of soluble thrombospondin, rabbit antiserum raised against thrombospondin, and human immune serum on cytoadherence of parasitized erythrocytes in ex vivo mesocecum vasculature. Preincubation of infected red cells with soluble thrombospondin or human immune serum inhibits binding of infected red cells to rat venular endothelium. Infusion of the microcirculatory preparation with rabbit antithrombospondin antibodies before perfusion of parasitized erythrocytes also resulted in decreased cytoadherence. In addition, incubation of infected cells with human immune sera obtained from malaria patients significantly inhibited the observed cytoadherence. Our results indicate that thrombospondin mediates binding of infected red cells to venular endothelium and may thus be involved in the pathogenesis of cerebral malaria.  相似文献   
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