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21.
Epidemiological studies have shown an association between consumption of alcoholic beverages and carcinoma of the large bowel, but studies in experimental models of colonic carcinogenesis have yielded conflicting results. We assessed the effects on azoxymethane-induced colonic carcinogenesis of both timing of chronic dietary ethanol consumption relative to carcinogen administration and quantity of ethanol consumption. Ten-week-old male Fischer 344 rats were given 11%, 22%, or 33% of calories as reagent ethanol or no ethanol by pair feeding with Lieber-DeCarli-type liquid diets providing comparable total carbohydrates, proteins, fats, and calories. Ten weekly s.c. injections of the bowel carcinogen azoxymethane (AOM), 7 mg/kg, were given to all rats in weeks 1-10. Three experimental groups were given their respective ethanol diet during acclimatization and AOM administration (preinduction and induction phases) and then were given the no-ethanol diet from week 11 until sacrifice in week 26 (postinduction phase). Three other groups received the no-ethanol diet during acclimatization and AOM administration and then were changed to their respective ethanol diet until sacrifice. The control AOM group received the no-ethanol diet throughout the study. Suppression of colonic tumorigenesis occurred in the groups with high levels of chronic dietary ethanol consumption during acclimatization and AOM administration: in the 33% and 22% diet groups, the prevalence of colonic tumors was 3% and 20% as compared with 50% in control (P less than 0.001 and P less than 0.02, respectively). Tumorigenesis in the left colon was more affected than in the right colon, as tumor prevalence in the left colon was decreased in both the 33% and 22% diet groups (0% in both versus 24% in control, P less than 0.005), whereas prevalence in the right colon was decreased only in the 33% diet group (3% versus 38%, P less than 0.001). By contrast, prevalence of colonic tumors in the 11% diet group was not significantly different from control. Chronic dietary ethanol consumption after AOM administration had no effect on tumor outcome, regardless of quantity of consumption. In an analogous study of [14C]AOM metabolism in rats fed the 33% diet during acclimatization and AOM administration, 14CO2 was exhaled at a slower rate than in rats fed no-ethanol diet (P = 0.05), indicating suppression of AOM metabolism.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
22.
De Leo V; Morgante G; Lanzetta D; D'Antona D; Bertieri RS 《Human reproduction (Oxford, England)》1997,12(2):357-360
We report the results of administration of danazol after suspension of
gonadotrophin-releasing hormone analogue (GnRHa) therapy for uterine
myomas. A total of 21 women with uterine myomas was treated with 100 mg
danazol for 6 months after GnRHa therapy. Uterine volume and endocrine
status were monitored monthly by ultrasound and assay of plasma
gonadotrophins, oestradiol and progesterone. The results show a rebound of
uterine volume about 30% less than in controls at the end of danazol
therapy. Menstrual cyclicity returned after 65 +/- 3 days in 16 subjects
and five patients remained amenorrhoeic. Hormone assays confirmed renewed
ovarian function in the women whose menstrual periods returned. Bone
mineral content was substantially reduced during GnRHa treatment but
improved significantly during danazol therapy even in the women who
remained amenorrhoeic. These results show the utility of danazol in
prolonging the therapeutic effects of GnRHa. The mechanism by which danazol
inhibits rebound of uterine volume may be due to its antiprogesterone
effects on uterine myomas.
相似文献
23.
Diagnostic distance of high grade prostatic intraepithelial neoplasia from normal prostate and adenocarcinoma. 下载免费PDF全文
R Montironi R Pomante P Colanzi D Thompson P W Hamilton P H Bartels 《Journal of clinical pathology》1997,50(9):775-782
OBJECTIVE: To develop a distance measure based methodology to support the morphological evaluation of high grade prostatic intraepithelial neoplasia (PIN), a direct precursor of prostate cancer. METHODS: Eight morphological and cellular features were analysed in 20 cases of high grade PIN found in radical prostatectomy specimens from patients with adenocarcinoma. The diagnostic distance was evaluated to measure the extent to which the feature outcomes of the individual high grade PIN cases differed from the expected outcome profile of normal prostate, low and high grade PIN, and cribriform and large acinar adenocarcinoma. The belief value for high grade PIN was evaluated with a Bayesian belief network (BBN). RESULTS: Complete separation existed between the cumulative absolute diagnostic distances of these 20 cases from the prototype feature outcomes of high grade PIN and normal prostate the values for which were < or = 3 (range 0 to 3) and > or = 9 (range 9 to 15), respectively. The distances from low grade PIN (range 3 to 9), cribriform adenocarcinoma (range 2 to 8), and large acinar adenocarcinoma (range 5 to 10) were intermediate and showed overlap in their distribution. When taking into consideration whether the severity of feature changes was increasing or decreasing in comparison with the category prototype outcomes, the cumulative directional diagnostic distances from high grade PIN ranged from -3 to +3. Positive distance values were seen relative to low grade PIN (range +3 to +9) and relative to normal prostate (range +9 to +15). Negative values were found relative to cribriform adenocarcinoma (range -8 to +2). The distance values from large acinar adenocarcinoma ranged from -2 to +4 and partly overlapped with those from the high grade PIN category. A bivariate scattergram derived from both diagnostic distance measures showed excellent separation between the groups' distances. BBN analysis confirmed the morphology based diagnosis. The distance evaluation resulted in 18 cases whose belief value for high grade PIN ranged from 0.60 to 0.87. In the remaining two cases the results of the BBN analysis showed a belief value of 0.50 and 0.57 for low grade PIN and of 0.49 and 0.38 for high grade PIN, respectively. CONCLUSIONS: Distance measure based methodology represents a useful diagnostic decision support tool for the accurate evaluation of high grade PIN. 相似文献
24.
M. P. Williams M. R. Hamilton J. C. Sercombe & R. E. Pounder 《Alimentary pharmacology & therapeutics》1997,11(4):705-710
Background: Dual therapy with ranitidine bismuth citrate plus clarithromycin twice daily for 14 days is an effective regimen for eradicating Helicobacter pylori infection.
Aim: To determine whether this regimen can be improved by the addition of a second antibiotic, tetracycline hydrochloride, whilst reducing the duration of treatment to 7 days.
Methods: Sixty-one out-patients were enrolled to this open treatment study. All had H. pylori infection, as determined by13 C-urea breath test and, for those undergoing endoscopy, by rapid urease test. Patients were treated with ranitidine bismuth citrate 400 mg, clarithromycin 500 mg and tetracycline hydrochloride 500 mg all twice daily for 7 days. Eradication of H.␣pylori was assessed by two separate 13 C-urea breath tests, the first 28–68 days after the completion of treatment, the second 28–162 days later. H. pylori infection was considered cured if both tests were negative.
Results: All 61 patients were included in the intention-to-treat efficacy analysis. Successful eradication of H.␣pylori was achieved in 55/61 patients (90 %; 95% CI: 82–98%). Fifty-nine out of sixty-one patients reported 100% compliance; one patient missed a single dose of medication and the other withdrew at 48 h due to nausea and vomiting. Minor adverse events were reported by 30/61 patients.
Conclusion: One-week triple therapy with ranitidine bismuth citrate, clarithromycin and tetracycline, all twice daily, is a safe and well-tolerated regimen which eradicates H. pylori in 90% of infected patients. 相似文献
Aim: To determine whether this regimen can be improved by the addition of a second antibiotic, tetracycline hydrochloride, whilst reducing the duration of treatment to 7 days.
Methods: Sixty-one out-patients were enrolled to this open treatment study. All had H. pylori infection, as determined by
Results: All 61 patients were included in the intention-to-treat efficacy analysis. Successful eradication of H.␣pylori was achieved in 55/61 patients (90 %; 95% CI: 82–98%). Fifty-nine out of sixty-one patients reported 100% compliance; one patient missed a single dose of medication and the other withdrew at 48 h due to nausea and vomiting. Minor adverse events were reported by 30/61 patients.
Conclusion: One-week triple therapy with ranitidine bismuth citrate, clarithromycin and tetracycline, all twice daily, is a safe and well-tolerated regimen which eradicates H. pylori in 90% of infected patients. 相似文献
25.
Medial talo-calcaneal coalition is an uncommon developmental anomaly consisting of a bony projection arising from the postero-medial aspect of the sustentaculum tali, which may articulate with another bony projection from the medial aspect of the talus. Fibrous, cartilaginous or bony ankylosis may occur. It usually presents in adolescents, and causes pain following exercise. It may cause a lump, and can predispose to flat foot and early osteoarthrosis. This condition is easily overlooked on routine views of the ankle, and may require oblique views and tomography for its detection and clarification. 相似文献
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29.
D. Morse M. O'Shea G. Hamilton N. Soltanpoor G. Leece E. Miller D. Brown 《Epidemiology and infection》1994,113(2):355-365
An outbreak of measles occurred in a community school and the surrounding area in Crowborough, East Sussex, UK, from December 1992 to February 1993. There were 96 suspected cases reported: 66 cases among 1673 students at one school and 30 community cases. The majority of suspected cases were in those aged 11-17 (78%), 2 cases occurred in infants < 1 year old and 8 cases in adults aged 18 years or over. Data collected on 60 (91%) of the 66 suspect school cases showed 56 (93%) had an illness which met a case definition of measles. Eighteen had confirmatory IgM measles antibody. Two cases were hospitalized. The local percentage uptake for measles immunization for the school age years affected varied between 64% and 84%. A survey of parents showed that approximately 74% of the students attending the school had a history of measles immunization. The immunization rates reported by parents for children who developed measles was 21%, (29% based on GP records) compared with 77% for those who remained well. Vaccine efficacy was estimated to be 92%. This outbreak, along with others recently reported in older unimmunized children in the UK, reinforces the need for catch-up immunization programmes to reach this susceptible group of adolescents. 相似文献
30.
M G Hamilton O N Dold 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1992,19(3):389-391
Spontaneous disappearance of an intracranial aneurysm after subarachnoid hemorrhage is an uncommon event and usually associated with severe cerebral vasospasm, giant aneurysms or the use of antifibrinolytics. We present a young woman who suffered a grade 5 subarachnoid hemorrhage with severe vasospasm caused by a small anterior communicating artery aneurysm. The patient underwent a slow recovery and two years later requested surgery. Angiography demonstrated complete disappearance of the aneurysm. The neurosurgeon should be aware that spontaneous thrombosis of cerebral aneurysms can occur and ensure that angiography is repeated when surgery is significantly delayed. 相似文献