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991.
992.
Kinsman J Harrison S Kengeya-Kayondo J Kanyesigye E Musoke S Whitworth J 《AIDS care》1999,11(5):591-601
As part of a large IEC (Information, Education and Communication)/STD intervention trial, a 19-lesson, comprehensive school-based AIDS education programme was implemented and evaluated in 50 primary and 16 secondary schools in 12 parishes of Masaka District, Uganda. A series of three teacher-training and evaluation workshops spread over a year was held in each parish, between which teachers implemented the programme in the classroom. One hundred and forty-eight teachers were trained and about 3,500 students were subsequently exposed to the programme. Both teachers and students responded positively, which suggests that this type of programme has much to offer young people who attend school. However, some problems were encountered: language, programme content, community resistance to teaching about condoms, and several practical issues. Proposed solutions include flexibility with the English language policy, alternative approaches to role play activities, targeting influential individuals with information about the need for young people to learn about safer sex, and a parallel community-based IEC programme to facilitate community acceptance of the need for the programme. In addition, implementation may be incomplete unless comprehensive AIDS education is fully incorporated into the curriculum, and properly examined. These findings are placed in the context of other life skills/AIDS education programmes being introduced both in Uganda and elsewhere in Africa. 相似文献
993.
Do the rich really die young? Alcohol-related mortality and social class in Great Britain, 1988-94 总被引:2,自引:1,他引:1
Aims. To determine whether social class is a major influence on alcohol-related mortality in the general, economically active population of Great Britain. Design and participants. Poisson regression of rates of mortality known to be directly caused by alcohol consumption by age, sex and social class in England, Wales and Scotland. Measurements. The measure of alcohol-related mortality is total deaths from ICD-9 categories 291; 303; 357.5; 425.5; 535.3; 305; 790.3; and 571.0-571.3 over the 7-year period 1988-94. (It excludes deaths for which alcohol-attributable fractions would need to be calculated.) The measure of social class is the British Registrar General's six-fold occupational classification, used to code census and death certification data. Findings. Alcohol-related mortality rates are higher for men in the manual occupations than in the non-manual occupations, but the relative magnitude depends on age. Men aged 25-39 in the unskilled manual class are 10-20 times more likely to die from alcohol-related causes than those in the professional class, whereas men aged between 55 and 64 in the unskilled manual class are only about 2.5-4 times more likely to die. For women in paid employment there is no consistent class gradient; younger women in the manual classes are more likely to die from alcohol-related causes, but for older women it is those in the professional class who suffer elevated mortality . Conclusions. Social class is a risk factor for alcohol-related mortality in Britain, although it is mediated by age and sex. Alcohol appears to be similar to other psychoactive substances, therefore, in that problem use is linked to social structural factors such as poverty, disadvantage and social class. This suggests that social interventions aimed at reducing poverty and inequality have the potential to reduce current levels of alcohol-related harm among the poorest groups in the community. 相似文献
994.
C N Harrison W Gregory G V Hudson S Devereux A H Goldstone B Hancock D Winfield A K MacMillan P Hoskin A C Newland D Milligan D C Linch 《British journal of cancer》1999,81(3):476-483
Hodgkin's disease is curable in the majority of patients, although a proportion of patients are resistant to or relapse after initial therapy. High-dose therapy with autologous stem cell support has become the standard salvage therapy for patients failing chemotherapy, but there have been reports of a high incidence of myelodysplasia/acute myeloid leukaemia (MDS/AML) following such treatment. Patients who receive such therapy form a selected group, however, who have already been subjected to other leukaemogenic factors, such as treatment with alkylating agents. In order to ascertain the true risk of MDS/AML, comparison must be made with other patients subjected to the same risks but not undergoing transplantation. We report a retrospective comparative study of 4576 patients with Hodgkin's disease from the BNLI and UCLH Hodgkin's databases, which includes 595 patients who have received a transplant. Statistical analysis including Cox's proportional hazards multivariate regression model with time-dependent covariates was employed. This analysis reveals that the risk of developing MDS/AML was dominated by three factors, namely quantity of prior therapy (relative risk [RR] 2.01, 95% confidence intervals [CI] 1.49-2.71, for each treatment block, P < 0.0001) and whether the patient had been exposed to MOPP (RR 3.61, 95% CI 1.64-7.95, P = 0.0009) or lomustine chemotherapy (RR 4.53, 95% CI 1.96-10.44, P = 0.001). Following adjustment for these factors in the multivariate model the relative risk associated with transplantation was 1.83 (95% CI 0.66-5.11, P = 0.25). This study provides no evidence of a significantly increased risk of MDS/AML associated with BEAM therapy and autologous transplantation in Hodgkin's disease. Concern over MDS/AML should not mitigate against the timely use of this treatment modality. 相似文献
995.
Dysregulated expression of beta-catenin marks early neoplastic change in Apc mutant mice, but not all lesions arising in Msh2 deficient mice 总被引:3,自引:0,他引:3
We have analysed the pattern of beta-catenin expression by immunohistochemistry in mice singly or multiply mutant for Apc, p53 and Msh2. We observed increased expression of beta-catenin in all intestinal lesions arising on an ApcMin+/- background. In all categories of lesion studied mosaic patterns of beta-catenin expression were observed, with the proportion of cells showing enhanced expression decreasing with increasing lesion size. p53 status did not alter these patterns. We also show that beta-catenin dysregulation marks pancreatic abnormalities occurring in ApcMin+/- and (ApcMin+/-, p53-/-) mice. In these mice both adenomas and adenocarcinomas of the pancreas arose and were characterized by increased expression of beta-catenin. We have extended these analyses to intestinal lesions arising in mice mutant for the mismatch repair gene Msh2. In these mice, increased expression of beta-catenin was again observed. However, in contrast with ApcMin+/- mice, a subset of lesions retained normal expression. Taken together, these findings show that increased expression of beta-catenin is an efficient marker of early neoplastic change in both murine intestine and pancreas in Apc mutant mice. However, we also show that dysregulation of beta-catenin is not an obligate step in the development of intestinal lesions, and therefore that genetic events other than the loss of Apc function may initiate the transition from normal to neoplastic epithelium. 相似文献
996.
Pharmacological blockade or genetic deletion of substance P (NK(1)) receptors attenuates neonatal vocalisation in guinea-pigs and mice 总被引:4,自引:0,他引:4
Rupniak NM Carlson EC Harrison T Oates B Seward E Owen S de Felipe C Hunt S Wheeldon A 《Neuropharmacology》2000,39(8):1413-1421
The regulation of stress-induced vocalisations by central NK(1) receptors was investigated using pharmacological antagonists in guinea-pigs, a species with human-like NK(1) receptors, and transgenic NK1R-/- mice. In guinea-pigs, i.c.v. infusion of the selective substance P agonist GR73632 (0.1 nmol) elicited a pronounced vocalisation response that was blocked enantioselectively by the NK(1) receptor antagonists CP-99,994 and L-733,060 (0.1-10 mg/kg). GR73632-induced vocalisations were also markedly attenuated by the antidepressant drugs imipramine and fluoxetine (30 mg/kg), but not by the benzodiazepine anxiolytic diazepam (3 mg/kg) or the 5-HT(1A) agonist buspirone (10 mg/kg). Similarly, vocalisations in guinea-pig pups separated from their mothers were blocked enantioselectively by the highly brain-penetrant NK(1) receptor antagonists L-733,060 and GR205171 (ID(50) 3 mg/kg), but not by the poorly brain-penetrant compounds LY303870 and CGP49823 (30 mg/kg). Separation-induced vocalisations were also blocked by the anxiolytic drugs diazepam, chlordiazepoxide and buspirone (ID(50) 0.5-1 mg/kg), and by the antidepressant drugs phenelzine, imipramine, fluoxetine and venlafaxine (ID(50) 3-8 mg/kg). In normal mouse pups, GR205171 attenuated neonatal vocalisations when administered at a high dose (30 mg/kg) only, consistent with its lower affinity for the rat than the guinea-pig NK(1) receptor. Ultrasound calls in NK1R-/- mouse pups were markedly reduced compared with those in WT pups, confirming the specific involvement of NK(1) receptors in the regulation of vocalisation. These observations suggest that centrally-acting NK(1) receptor antagonists may have clinical utility in the treatment of a range of anxiety and mood disorders. 相似文献
997.
998.
Survival of colorectal cancer cell lines treated with paclitaxel, radiation, and 5-FU: effect of TP53 or hMLH1 deficiency 总被引:3,自引:0,他引:3
Kennedy AS Harrison GH Mansfield CM Zhou XJ Xu JF Balcer-Kubiczek EK 《International journal of cancer. Journal international du cancer》2000,90(4):175-185
Clonogenic survival and early cell death during treatment of human colon carcinoma cells were investigated following X-irradiation (IR) alone, IR followed by 5-FU for 24 h, and Taxol administered 24 h before IR and 5F-U. The investigated cell lines were: HCT116, 40-16 clonally derived from HCT116, and two HCT116 variants: N6CHR3 expressing hMLH1, and TP53 null cells denoted HCT116 p53-/-. The objective was to determine efficacy of the combined treatment and to correlate response with constitutive levels of TP53, WAF1, and hMLH1 proteins, as well as with mRNA levels of the apoptosis-related genes survivin, BNIP3, and MYC. At the end of treatment with 5-FU, the proportion of viable cells was between 0.65 and 0.70 for all cell lines. Additional cell loss occurred in 40-16 and HCT116 p53-/- cells following administration of Taxol before IR and 5-FU. Radiation sensitivity was unaffected by combined treatments, except for Taxol, irradiation, and 5-FU sequence in the HCT116 p53-/- and 40-16 cell lines, where radiation sensitivity determined by clonogenic survival curve slopes was doubled or quadrupled, respectively. Under our present experimental conditions, treatment response did not correlate with TP53 or hMLH1 status, but was associated with apoptosis-related genes, most notably BNIP3. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 175-185 (2000). 相似文献
999.
Prognostic significance of immunohistochemical micrometastases in node negative gastric cancer patients 总被引:11,自引:0,他引:11
Harrison LE Choe JK Goldstein M Meridian A Kim SH Clarke K 《Journal of surgical oncology》2000,73(3):153-157
BACKGROUND AND OBJECTIVES: The purpose of this study is to examine the prognostic significance of immunohistochemical (IHC) evidence of lymph node (LN) metastases in histologic node negative gastric cancer patients. METHODS: Retrospective review from 1981 to 1998 revealed 25 patients resected for T1-4N0M0 gastric and gastroesophageal (GE) junction adenocarcinoma. All cases were reviewed and histopathologic parameters were defined for each primary tumor. All LNs underwent IHC analysis with the epithelial marker CAM 5.2. Data are reported as median (range). RESULTS: The median number of LN resected was 7 (range 1-33). The median follow-up time was 25 months (range 4-195) with an overall 5-year survival rate of 55%. For patients with IHC evidence of LN micrometastasis (n = 9), the 5-year survival rate was significantly decreased (35%) compared to a 66% 5-year survival rate for IHC negative patients (n = 16, P = 0.05). CONCLUSIONS: The presence of IHC-detected LN micrometastases correlates with worse prognosis for patients with histologic node negative gastric cancer. IHC may be a useful additional staging modality in this subset of patients. 相似文献
1000.
1. Endomorphin-1 (E1) is a peptide with high affinity and selectivity for the mu-opioid receptor. The aim of this study was to determine if endomorphin-1 caused desensitization and down-regulation of the mu-opioid receptor expressed in Chinese hamster ovary cells. 2. Following 10 microM E1 pre-treatment, desensitization was assessed by measuring cyclic AMP inhibition, down-regulation was assessed by [(3)H]-diprenorphine ([(3)H]-DPN) binding and immuno-blotting. 3. Pre-treatment of CHO mu cells with 10 microM E1 for 11 and 18 h caused significant reduction in cyclic AMP inhibition. (11 h=39.0+/-16.7%, 18 h 47.0+/-11.1% reduction). 4. At 18 h E1 pre-treatment there was an enhancement (4.5 fold) of cyclic AMP production under forskolin stimulated conditions accompanied by a small rightward shift in the concentration-response curve (pEC(50) control=7.8+/-0.3, pEC(50) E1=7.3+/-0.2) when cells were re-challenged with E1. 5. In membranes prepared from untreated and 0.5 h E1 pre-treated cells, addition of GTP gamma S produced a significant rightward shift in the concentration response curves for E1 displacement of [(3)H]-DPN (0 h K(i) control=7.86+/-0.11, GTP gamma S=7.37+/-0.15; 0.5 h K(i) control=7.92+/-0.12, GTP gamma S=7.36+/-0.08) This was not observed in membranes prepared from cells that had been treated with E1 for 18 h (18 h K(i) control=7.69+/-0. 11, GTP gamma S=7.75+/-0.08). 6. In whole cells E1 treatment caused a rapid loss of cell surface receptors such that at 0.5 h there was a 30.5+/-1.5 reduction (this was unchanged for 18 h). In crude membranes a loss of receptors was also observed using radioligand binding or immuno-blotting protocols. 7. These data show that E1 causes desensitization and down-regulation of the rat mu-opioid receptor expressed in CHO cells. However, these two responses appear temporally distinct. 相似文献