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81.
Nickel(II) acetate (NiAcet), a soluble nickel salt known to be an effective initiator of renal epithelial tumors in adult rats, was studied for possible transplacental carcinogenicity. Pregnant F344/NCr rats were given NiAcet i.p. either once a day on day 17 (90 mumol/kg body wt; group 1) or twice on days 16 and 18 of gestation (45 mumol/kg body wt/day; group 2). Offspring of these rats were further subdivided into groups 1A and B and 2A and B, respectively. Groups 1A and 2A received ordinary tap water while groups 1B and 2B received drinking water containing 500 p.p.m. sodium barbital (NaBB) during weeks 4-85 of age. Renal cortical epithelial and renal pelvic transitional epithelial tumors occurred in male offspring given NiAcet prenatally followed by NaBB postnatally (group 1B, 15 tumors in 8/15 rats; group 2B, 10 tumors in 7/15), but not in male offspring given NiAcet only (0/32) or in controls given prenatal sodium acetate (NaAcet) only (0/15) and rarely in males given NaAcet followed by the promoter NaBB (1/15). No renal tumors occurred in females. Pituitary tumor incidence was significantly higher in offspring of both sexes given NiAcet prenatally (NaAcet controls, 4/31, both sexes combined; group 1A, 14/33, P = 0.012; group 2A, 14/31, P = 0.008). Pituitary tumors appeared much earlier in rats given NiAcet prenatally, with or without postnatal NaBB, and often were malignant by cytologic and histologic criteria including pleomorphism and invasion of adjacent structures, unlike the well-differentiated adenomas that occurred less frequently in untreated rats. These results are the first evidence that Ni(II) is a potent transplacental initiator of epithelial tumors in fetal rat kidney and a complete transplacental carcinogen for rat pituitary. 相似文献
82.
Use of cigarette tobacco by large proportions of the population of Middle Eastern countries has been reported; however, little is known about smoking behavior in one of America's fastest growing minorities, the Arab Americans. The purpose of this study was to examine cigarette smoking behavior of 237 randomly selected Arab American adults from a telephone listing in the Detroit area. Participants lived in the geographic Arab American community and identified with a Middle Eastern cultural heritage. Nurses, who spoke both English and Arabic, interviewed one adult family member using the 59-item self-report from the Cardiovascular Risk Factor Survey developed by Rice. Mean age of respondents was 40.4 years, 97 percent had been born in the Middle East, and 67 percent had been living in the United States 15 years or less. Current smokers rate was 38.9 percent, former smokers rate was 11.1 percent, never smokers rate was 50 percent, and the quit ratio (proportion of ever smokers who are former smokers) was 22.2 percent. Fifty-four percent of the current smokers were between 25 and 34 years of age; fewer women than men were former smokers, and the highest proportion of current smokers were Lebanese. Subjects who had smoked for the longest time were the least well educated. Arab Americans in this sample had a higher smoking rate, a lower quitting rate, and a much lower quit ratio when compared with national and State of Michigan data. With the growing numbers of Middle Eastern immigrants, there is potential for a dramatic increase in smoking-related health problems. 相似文献
83.
Joan Prudic Mark Olfson Steven C Marcus Rice B Fuller Harold A Sackeim 《Neuropsychopharmacology》2004,55(3):301-312
BACKGROUND: Clinical trials indicate that electroconvulsive therapy (ECT) is the most effective treatment for major depression, but its effectiveness in community settings has not been examined. METHODS: In a prospective, naturalistic study involving 347 patients at seven hospitals, clinical outcomes immediately after ECT and over a 24-week follow-up period were examined in relation to patient characteristics and treatment variables. RESULTS: The sites differed markedly in patient features and ECT administration but did not differ in clinical outcomes. In contrast to the 70%-90% remission rates expected with ECT, remission rates, depending on criteria, were 30.3%-46.7%. Longer episode duration, comorbid personality disorder, and schizoaffective disorder were associated with poorer outcome. Among remitters, the relapse rate during follow-up was 64.3%. Relapse was more frequent in patients with psychotic depression or comorbid Axis I or Axis II disorders. Only 23.4% of ECT nonremitters had sustained remission during follow-up. CONCLUSIONS: The remission rate with ECT in community settings is substantially less than that in clinical trials. Providers frequently end the ECT course with the view that patients have benefited fully, yet formal assessment shows significant residual symptoms. Patients who do not remit with ECT have a poor prognosis; this underscores the need to achieve maximal improvement with this modality. 相似文献
84.
85.
Estil Y. Strawn Jr. MD Miles J. Novy MD Kenneth A. Burry MD Cynthia L. Bethea PhD 《American journal of obstetrics and gynecology》1995,172(6):1837-1844
Objective: Our purpose was to determine whether insulin-like growth factors I and II preferentially stimulate uterine leiomyoma cells versus myometrial cells in monolayer culture.Study design: Leiomyomas and normal myometrium were obtained at hysterectomy from five premenopausal women. Specimens were enzymatically digested for use in primary monolayer cell cultures. By use of serum-free media, insulin-like growth factor I or II was added in 1, 10, and 100 ng/ml concentrations to both cell types with the patient serving as her own control. Cell number, prolactin production, and proliferative index values were measured on day 15 of cell culture.Results: Significant increases in cell number were found in the leiomyoma cultures (p < 0.05) treated with 10 and 100 ng/ml insulin-like growth factors I but not with insulin-like growth factos II. Neither factor exerted a stimulatory effect on myometrial cells.Conclusion: Insulin-like growth factor sI preferentially stimulates leiomyoma cells in monolayer culture. These results suggest an autocrine-paracine role in vivo for this factor in conjuction with gonadal steroids in promoting leiomyoma growth. 相似文献
86.
87.
1 The standard drug for the treatment of arsenic poisoning is BAL (dimercaprol). BAL possesses marked side-effects and a low safety ratio, drawbacks which new BAL analogues, DMPS and DMSA, do not possess. 2 The efficacy of three chelating agents, BAL, DMPS and DMSA, has been evaluated as a treatment for systemic organic arsenic poisoning, induced by intravenous dichloro(2-chlorovinyl)arsine (lewisite) administration to rabbits. Equimolar dosing schedules were used based upon realistic doses for the most toxic agent, BAL. 3 It was concluded that all three dimercapto chelating agents provided significant protection against the lethal systemic effects of lewisite, and, under the test conditions reported here, there was no significant difference between them in therapeutic efficacy. 4 The cause of mortality following intravenous lewisite in treated and untreated rabbits was pulmonary damage. 5 It is considered that DMPS and DMSA are worthy of further study as replacements for BAL in the treatment of systemic poisoning by lewisite. 相似文献
88.
89.
The Workup for Bariatric Surgery Does Not Require a Routine Upper Gastrointestinal Series 总被引:1,自引:0,他引:1
Andrew J Ghassemian Kenneth G MacDonald MD Paul G Cunningham MD Melvin Swanson PhD Brenda M Brown MRA Patricia G Morris BSN Walter J Pories MD 《Obesity surgery》1997,7(1):16-18
Background: Morbid obesity is a serious disease that afflicts over five million Americans, threatening their health with such
co-morbidities as diabetes, arthritis, pulmonary failure and stroke. Surgery is the only effective therapy, providing long-term
control of weight, diabetes, pulmonary failure, and hypertension for as long as 14 years. Because the operation presents a
major expense, this study examined whether X-ray examination of the gut could be omitted safely as a cost-saving measure.
Methods: The records of 814 consecutive morbidly obese patients who underwent gastric bypass were reviewed to determine: (1)
whether these individuals had undergone an upper gastro-intestinal (GI) series, and (2) if these studies influenced therapy
or caused cancellation or postponement of surgery. Results: Of the 814 patients, 657 (80.7%) underwent a preoperative GI radiography.
Of these examinations, 393 (59.8%) were normal, with the following abnormalities in the remaining 264: hiatal hernia, 164;
esophageal reflux, 39; Schatzki's ring, 18; small bowel diverticula, four; renal stones, four; malrotation, three; gall stones,
two; pyloric ulcer, one; possible pelvic mass, one; calcified leiomyoma, one; and dysphagial lusoria, one. None of these findings
resulted in cancellation or a delay in surgery. Conclusions: The upper GI series can be safely omitted from the routine preoperative
evaluation of patients undergoing gastric bypass. At a cost of $741.00 per examination, this change represents significant
potential savings. Similar evaluations of other routine preoperative tests may well provide a better basis for the evaluation
of these complex patients. 相似文献