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31.
Recently, the beneficial role of steroids for acute laryngotracheobronchitis has been more clearly defined for both intubated and unintubated patients. However, corticosteroids also improve the clinical signs of airway haemangiomata. Two patients are described who illustrate how this can be a source of diagnostic confusion.  相似文献   
32.
Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
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Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine.  相似文献   
34.
Tobacco, alcohol, and marijuana are among the most commonly used drugs during adolescence. Initiation of marijuana use typically peaks at age 15, with risk of initiation continuing throughout adolescence. The goal of the current study was to prospectively examine the influence of age of marijuana initiation on four outcomes: physical health, mental health, illicit drug use other than marijuana, and marijuana-use related consequences at age 18. We controlled for several important predictors of adolescent drug use and its associated consequences, including demographics, social bonding variables, personality variables, and recent use of marijuana. Baseline survey data were collected in 1984 at grade 7 and follow up surveys were conducted at grades 8, 9, 10, and 12 (N = 2079). This initiates-only sample was 47% female, 66% White, 11% African American, 13% Hispanic, 5% Asian, and 5% other race or ethnicity. Findings indicated that age of initiation predicted marijuana consequences and other illicit drug use after controlling for demographic, social, and behavioral factors. However, once frequency of recent marijuana use was included in the models, age of initiation was only associated with other illicit drug use. Both primary and secondary prevention are needed to curb marijuana use and its associated harms.  相似文献   
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Smoking initiation typically occurs in adolescence and increases over time into emerging adulthood. Thus adolescence and emerging adulthood compose a critical time period for prevention and intervention efforts. To inform these efforts, this study used latent growth mixture modeling to identify 6 smoking trajectories from ages 13 to 23 among 5,914 individuals: nonsmokers (28%), stable highs (6%), early increasers (10%), late increasers (10%), decreasers (6%), and triers (40%). By age 23, the trajectories merged into 2 distinct groups of low- and high-frequency and their standing on age 23 outcomes reflected this grouping. Consideration of these results can help researchers identify at-risk individuals before their smoking becomes too problematic, providing an opportunity for intervention and possible prevention of nicotine dependence.  相似文献   
37.
OBJECTIVES: We used data gathered from 6259 youths between the ages of 13 and 23 years to compare trends in smoking among 4 racial/ethnic groups. METHODS: We weighted trend data to represent baseline respondent characteristics and evaluated these data with linear contrasts derived from multiple regression analyses. RESULTS: Although African Americans exhibited higher initiation rates than Whites, they exhibited consistently lower rates of regular smoking than both Whites and Hispanics. This seeming anomaly was explained by African Americans' lower rates of transition to regular smoking and greater tendency to quit. Racial/ethnic disparities were accounted for by differences in pro-smoking influences. CONCLUSIONS: Reducing racial/ethnic disparities in smoking may require reducing differences in the psychosocial factors that encourage smoking.  相似文献   
38.
The ability of the Theory of Planned Behavior, Social Learning Theory, Social Attachment Theory, and Problem Behavior Theory to predict smoking at Grade 10 was tested against an integrated model incorporating predictors from all the theories. The integrated model also tested whether constructs from each theory contribute distinct variance to the prediction of smoking. Predictors measured at Grade 7 (in 1985) were used to model smoking 3 years later (in 1988) among 4186 youth, using logistic regression. Constructs emphasized by each theory were important, independent predictors of later smoking. The integrated model was superior to all of the theory-based models. A few predictors varied for current vs. frequent smoking outcomes. Results emphasize the need for a multifaceted approach to understanding and preventing adolescent smoking.  相似文献   
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