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61.
Adolescent problem behavior, including substance use, schoolmisconduct and delinquency, is a national concern. Implicitin the concept of middle school is the recognition that studentswho develop positive social bonds with their school are morelikely to perform well academically, and refrain from misconductand other antisocial behavior. However, little scientific attentionhas been given to the complex interactions between middle schoolstudents and the school environment. Prior to implementing amiddle school problem behavior prevention program we conducteda survey in the seven middle schools in one US school district.Out of 4668 grade 6–8 students enrolled, 4263 (91.3%)completed the survey. Student–school bonding was positivelycorrelated with school adjustment (r = 0.49) and perceived schoolclimate (r = 0.77), but inversely correlated with problem behavior(r = –0.39 to –0.43). Problem behavior was significantlyhigher (P < 0.001) among males than females and among studentsin higher grades. Conversely, school bonding, climate and adjustmentwere significantly higher (P < 0.001) among females thanmales, but declined significantly from one grade to the next.The data support the conclusion that school bonding is associatedwith problem behavior. We describe the development of a multiple-componentintervention in middle schools designed to increase student–schoolbonding and prevent problem behavior.  相似文献   
62.
Circadian administration of chemotherapy has been reported to decrease toxicity and possibly enhance efficacy. Between March 1991 and December 1993, 18 evaluable patients with progressive, hormone-refractory metastatic prostate cancer were treated in this phase II trial of circadian infusion floxuridine (FUDR). The drug was delivered through a central venous catheter using a CADD-Plus computerized pump such that approximately 70% of the drug was administered between 3 and 9 p.m. and the rest (30%) was administered between 9 p.m. and 3 p.m. The dose of FUDR was 0.15 mg/kg/day × 14 days every 4 weeks. A total of 79 complete cycles was administered.Two of 18 evaluable patients (11.1%) had decreases in PSA lasting five and eight months. No objective responses or improvement in bone scans was noted. The major toxicity observed was diarrhea. Although circadian infusion FUDR is feasible and tolerable, it has limited activity in hormone refractory prostate cancer.  相似文献   
63.
A combination of celecoxib and selenium was used in a randomized double-blind Phase II trial as a preliminary study to a multicenter Phase III colorectal cancer chemoprevention trial using these two agents together. The purpose of this trial was to determine whether high-selenium baker's yeast [(Saccharomyces cerevisiae) 200 microg once daily] in combination with celecoxib (400 mg once daily) altered the steady-state plasma concentration of celecoxib or produced clinically significant toxicities. Seventy-three healthy subjects (ages 40-75 years) were recruited to the 6-week study from the general local population and were randomized to either the celecoxib plus selenized baker's yeast group or the celecoxib plus placebo group after a 2-week run in period of celecoxib only. Blood samples were taken at baseline (to document that there was no evidence of celecoxib intake), after the 2-week run-in period on celecoxib to verify steady-state blood levels of this agent, and at end of study (4 weeks postrandomization). Toxicities were monitored at 2 weeks after initiation of celecoxib, at 4 weeks after initiation, and at the end of the study. Blood level concentrations of celecoxib did not differ between the two groups as determined by high-performance liquid chromatography analysis nor were there significant differences in blood chemistry values between the two groups. Subjects' self-report of general physical toxicities was uncommon and limited to National Cancer Institute toxicity grade 2 or less; however, 2 female participants (3%) were removed from the study medications because of grade 2 edema and significant weight gain after 2 and 2.5 weeks of celecoxib administration. In conclusion, high-selenium yeast and celecoxib can be taken at the described doses with minimum short-term negative effects. In future Phase III chemoprevention trials of celecoxib, weight gain should be carefully monitored, and participants should be made aware of this potential side effect before study entry.  相似文献   
64.
PURPOSE: Cancer accounts for 60.9 billion dollars in direct medical costs and 15.5 billion dollars for indirect morbidity costs. These estimates are derived primarily from national surveys or Federal databases. We derive estimates of the costs of cancer using administrative databases, which include claims and employment-related information on individuals insured by private or Medicare supplemental health plans. METHODS: A retrospective matched-cohort control analysis was performed using 1998 to 2000 databases with information on insurance claims, benefits, and health productivity for 3 million privately insured employees, their dependents, and early retirees. Study patients had new diagnoses of one of seven types of cancer (n = 12,709). Controls without cancer were matched at a 3:1 ratio by demographics. A variable follow-up length was used (maximum of 2 years). Direct costs included health care costs for patients and deductibles and copayments for caregivers. Indirect costs of work absence and short-term disability (STD) were calculated for a subgroup of cancer patients and caregivers. RESULTS: Mean monthly health care costs ranged from 2,187 dollars for prostate cancer to 7,616 dollars for pancreatic cancer, most often driven by hospitalization. Costs for controls were 329 dollars per month. Indirect morbidity costs to employees with cancer averaged 945 dollars, a result of a mean monthly loss of 2.0 workdays and 5.0 STD days. CONCLUSION: The economic burden of cancer is substantial. It is feasible to derive tumor-specific estimates of direct and indirect costs for large numbers of cancer patients using administrative databases. Policy makers charged with providing annual cost-of-cancer estimates should incorporate data obtained from a broad range of sources.  相似文献   
65.
Human papillomavirus (HPV) subtypes 16 and 18 are sexually transmitted and have been associated with an increased incidence of several anogenital tumors. Although previous epidemiological studies have suggested that sexual behaviors such as an early age at first intercourse and larger numbers of sexual partners are also related to an increased risk of prostate cancer, seroepidemiological studies of these infectious agents in relation to prostate cancer have produced differing results. To further evaluate this potential relationship, we completed a population-based control study in King County, Washington. Middle-aged (40-64 years) men diagnosed with prostate cancer (n = 642) were ascertained through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results cancer registry between January 1993 and December 1996. Controls (n = 570) of similar age were selected from the same population as the cases by random digit dialing. Overall, there was no association between serological evidence of prior HPV-16 (adjusted odds ratio, 1.06; 95% confidence interval, 0.71-1.57) or HPV-18 (adjusted odds ratio, 1.36; 95% confidence interval, 0.69-2.69) infection and the risk of prostate cancer. Analyses of clinical features demonstrated no relationship between HPV infection status and Gleason score, stage of disease, or a combined measure of disease aggressiveness. Our findings indicate that HPV-16 and HPV-18 are not associated with prostate cancer risk.  相似文献   
66.
Colorectal adenomatous polyps are considered to be the precursor lesion of colorectal cancer (1-3). Greater understanding of the association between smoking and adenoma development enable better detection and prevention of colorectal cancer. This study was conducted in men and women, ages 40-80, participating in a randomized trial testing the effects of wheat bran fiber supplement on adenoma recurrence. First, we investigated smoking exposure (status, cigarettes/day, and years of smoking) and colorectal adenoma characteristics (location, histology, size, and multiplicity) at baseline colonoscopy (n = 1429). Second, we evaluated smoking exposure and adenoma recurrence (n = 1304). The prevalence of distal versus proximal adenomas was greater for < or =30 cigarettes/day [odds ratio (OR), 1.48; 95% CI, 1.02-2.16] and 15 to <25 years of smoking (OR, 1.95; 95% CI, 1.23-3.09) compared with never smokers. Tubular versus villous histology prevalence was increased for > or =30 cigarettes and > or =35 years of smoking (OR, 1.74; 95% CI, 1.21-2.49 and OR, 1.74; 95% CI, 1.24-2.45, respectively) compared with never-smokers. Years of smoking increased prevalence of multiple versus single adenomas, whereas cigarettes/day and years of smoking were associated with large adenomas (> or =1 cm) prevalence as compared with small lesions (< or =0.5 cm). Greater than 35 years of smoking was significantly associated with an increased risk of adenoma recurrence (OR, 1.42; 95% CI, 1.01-1.98). These results suggest that the association between smoking and adenoma prevalence varies by the characteristic of the lesion. Furthermore, the association between smoking and adenoma recurrence is modest and was only significant after a long duration of exposure. Additional investigations that characterize the genetic changes in specific subgroups of prevalent and recurrent adenomas associated with smoking exposure are needed.  相似文献   
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Systemic Lupus Erythematosus: Perinatal and Neonatal Implications   总被引:2,自引:0,他引:2  
Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder that can affect almost all organ systems in the body. It is most common in women of childbearing age and may cause multiple peripartum complications. This article reviews the pathophysiology of SLE and the effects of SLE on fertility and pregnancy. The complexities of managing a pregnant patient with SLE are reviewed, and the importance of interdisciplinary collaboration discussed, as well as the effects of SLE on the fetus and a review of neonatal lupus erythematosus. Finally, a case report of a pregnant patient with SLE with challenging clinical management issues is presented.  相似文献   
70.
Objective To assess the efficacy of oral oestriol in the prevention of recurrent Urinary tract infections in elderly women.
Design Double-blind, randomised, parallel group, placebo controlled trial
Setting Urogynaecology Unit at King's College Hospital with some women recruited from the geriatric units of St. Pancras Hospital and Dulwich Hospital, London (UK).
Participants Seventy-two postmenopausal women older than 60 years of age (mean 73.2 years) suffering from recurrent urinary tract infections.
Intervention Oral oestriol (3 mg per day) or placebo for six months.
Main outcome measures Urinary tract infection rates.
Results The study was difficult to conduct because of its design and the age of the participants. Oral oestriol (3 mg per day) was not shown to be superior to placebo in the prevention of recurrent urinary tract infections, but both oestriol and placebo improved urinary symptoms during the trial.
Conclusion The power of the study might have been too low to detect a significant difference between the groups, or oral oestriol(3 mg per day) may have been either the wrong dose or the wrong route of administration for this indication.  相似文献   
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