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Abstract: Research suggests that cigarette use declines when women find out they are pregnant, increasing again after the birth. Pregnancy may provide many women with a substantial impetus to stopping smoking. Also, rates of smoking cessation and reduction may be class-related, with the highest socioeconomic-status groups manifesting higher rates of reduction. Using data from the Mater Hospital-University of Queensland Study of Pregnancy, we report family income related to rates of smoking before, during and after a pregnancy. Before becoming pregnant, 45.9 per cent of women in the sample were smokers. This declined to 34.7 per cent of women at their first clinic visit. Rates of heavy smoking (20 or more cigarettes per day) had returned to earlier levels by the six-month (after birth) follow-up. Women in the lowest family-income group had the highest rates of cigarette use before, during and after their pregnancy. Of the lowest family-income group, 8.4 per cent were heavy smokers before, during and after their pregnancy, compared with 2.8 per cent of women in the highest family-income group. Smoking cessation rates were highest in the highest family-income group (those who smoked least), but relapse rates after the birth were similar for all income groups. Arresting rates of smoking relapse by pregnant women should be seen as a major public health priority  相似文献   
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Lewis system alterations in gastric carcinogenesis   总被引:1,自引:0,他引:1  
Alterations in the expression of type 1 blood group-related antigens (Lewis a and b) were examined immunohistochemically in 371 consecutives gastric biopsy and 80 surgical specimens from patients of gastric carcinoma. The ABH and Lewis phenotype and secretor status of the patients were correlated with histologic findings. An anomalous expression of Lewis a antigen was found in 88 of 249 gastric biopsy specimens of Lewis (a-b+) phenotype patients. The prevalence of this anomaly increased with the evolution of the premalignant process, in agreement with the commonly accepted model of gastric carcinogenesis. Thus, anomalous Lewis a antigen appeared in 66.6% of gastric dysplasia cases, in 64.6% of intestinal metaplasia, in 15.4% of atrophic gastritis, and in 7.4% of superficial gastritis. No alterations were found in subjects with normal gastric mucosa. Forty-seven of the 49 Lewis (a-b+) phenotype gastric carcinoma patients showed antigenic alterations in tumor cells (anomalous Lewis a antigen in 36 and loss of Lewis antigens in 11). In 26 of these gastric specimens an anomalous Lewis a antigen was present in areas of intestinal metaplasia and/or dysplasia away from the area of neoplastic transformation. The expression of Lewis a antigen in Lewis (a-b+) phenotype patients is a frequent phenomenon in gastric neoplastic cells and could result from the blocked synthesis of Lewis b antigen with accumulation of its precursors. These findings suggest that, during gastric carcinogenesis, antigenic alterations may precede neoplastic transformation. An anomalous Lewis a antigen could constitute a significant index of severity of the histologic lesion and contribute to identifying high-risk individuals.  相似文献   
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BACKGROUND: Immunologic data, such as IgE and interleukin 4, tend to have positively skewed distributions with a long tail of larger values. This renders analyses based on normal distribution theory questionable (eg, t tests and analysis of variance) and distorts the sample mean as a measure of central tendency. These problems can be addressed through analysis of log-transformed data. Data analyzed in this fashion are summarized with the geometric mean. OBJECTIVE: To elucidate the use of the logarithmic transform and the geometric mean in the analysis of immunologic data. METHODS: The analysis may be conducted by transforming the data to a logarithmic scale to achieve a bell-shaped (approximately normal) distribution. The bell-shaped distribution needed to validate statistical inferences is only achieved in the transformed scale. In summarizing the research findings, the statistical analyst usually will transform means and confidence intervals from the logarithmic scale back to the original scale of measurement. Statistical inferences in the log scale remain valid for the data. The result of back transforming the mean of logarithmic values to the original scale is the geometric mean. This statistic is less subject to distortion by the unusually large values in the tail of the positively skewed distribution of the data. RESULTS: A brief example is used to illustrate this type of analysis. Conclusions: Logarithmic transformation permits valid statistical inference for positively skewed immunologic data. A result of this analysis is the geometric mean, which is a better measure of central tendency of this data type than the usual sample mean.  相似文献   
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The molecular link between obesity and beta cell failure that causes diabetes is difficult to establish. Here we show that a conditional knockout of insulin receptor substrate 2 (Irs2) in mouse pancreas beta cells and parts of the brain--including the hypothalamus--increased appetite, lean and fat body mass, linear growth, and insulin resistance that progressed to diabetes. Diabetes resolved when the mice were between 6 and 10 months of age: functional beta cells expressing Irs2 repopulated the pancreas, restoring sufficient beta cell function to compensate for insulin resistance in the obese mice. Thus, Irs2 signaling promotes regeneration of adult beta cells and central control of nutrient homeostasis, which can prevent obesity and diabetes in mice.  相似文献   
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Objective The purpose of this study is to determine the control of acute and delayed chemotherapy-induced nausea and vomiting (CINV) in patients receiving moderately emetogenic chemotherapy (MEC) and highly emetogenic chemotherapy (HEC) with the combined use of palonosetron and olanzapine, and dexamethasone with the dexamethasone given on day 1 only. Materials and methods Forty chemotherapy-naive patients received on the day of chemotherapy, day 1, an anti-emetic regimen consisting of dexamethasone, palonosetron, and olanzapine. Patients continued olanzapine for days 2–4 after chemotherapy administration. Patients recorded daily episodes of emesis, daily symptoms utilizing the M.D. Anderson Symptom Inventory, and the utilization of rescue therapy. Results For the first cycle of chemotherapy, the complete response (no emesis, no rescue) for the acute period (24 h post-chemotherapy) was 100%, the delayed period (days 2–5 post-chemotherapy) 75%, and the overall period (0 120 h post-chemotherapy) 75% in 8 patients receiving HEC and was 97, 75, and 72% in 32 patients receiving MEC. Patients with no nausea for the acute period was 100%, the delayed period 50%, and the overall period 50% in 8 patients receiving HEC and was 100, 78, and 78% in 32 patients receiving MEC. Discussion The complete response and control of nausea in subsequent cycles of chemotherapy were not significantly different from cycle one. Conclusion Olanzapine combined with a single dose of dexamethasone and a single dose of palonosetron was very effective in controlling acute and delayed CINV in patients receiving both HEC and MEC.  相似文献   
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