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921.
922.
The epidemiology of bladder cancer in West Yorkshire. A preliminary report on non-occupational aetiologies 总被引:5,自引:1,他引:4
This is a preliminary report of a large case-control study onthe epidemiology of bladder cancer in West Yorkshire. Severalaspects of the life-style of cases and controls are investigatedhere. These show statistically significant differences betweencases and controls in the smoking of cigarettes and some inconsistentdifferences for saccharin consumption and coffee drinking. Alcoholconsumption proved to be the same in both the case and controlgroups. 相似文献
923.
924.
925.
Lymphocyte transformation in human toxoplasmosis 总被引:9,自引:0,他引:9
926.
Interruption of the aortic arch is an uncommon malformation in which there is no direct continuity between the aortic arch and the descending aorta, the latter arising through a patent ductus arteriosus. Three types are described, depending upon the site of interruption in relation to the arch vessels. A large ventricular septal defect is present in 94% of cases. It is to be distinguished from aortic arch atresia, which should be regarded as a severe form of preductal coarctation in which the luminal continuity of the arch and descending aorta is absent. Three cases are described: the first demonstrates the natural outcome of the uncorrected anomaly with progression to Eisenmenger's syndrome; the second illustrates the feasibility of surgical treatment in the neonate; the third is an example of total correction of aortic arch interruption with the common associated anomalies. Diagnosis in infancy is difficult in view of the paucity of definite clinical criteria. Surgery in the infant should consist of reconstruction of the aortic arch together with pulmonary artery banding. In older children total correction can usually be performed electively in a two-stage procedure. 相似文献
927.
928.
We report in silico identification and characterisation of a novel member of the ras association domain family 1 (RASSF1)/NORE1 family, namely, RASSF2, located at chromosomal region 20p13. It has three isoforms, all contain a ras association domain in the C-terminus. The longest isoform RASSF2A contains a 5' CpG island. RASSF2A was cloned from a brain cDNA library and directly sequenced, confirming the genomic gene structure. In previous reports, we and others have demonstrated that RASSF1A is epigenetically inactivated in a variety of cancers, including sporadic colorectal cancer (CRC). In the present report, we analysed the methylation status of RASSF2A promoter region CpG island in sporadic CRC and compared it to K-ras mutation status. RASSF2A promoter region CpG island was hypermethylated in a majority of colorectal tumour cell lines (89%) and in primary colorectal tumours (70%), while DNA from matched normal mucosa was found to be unmethylated (tumour-specific methylation). RASSF2A expression was reactivated in methylated tumour cell lines after treatment with 5-aza 2-deoxycytidine. RASSF2A methylation is an early event, detectable in 7/8 colon adenomas. Furthermore, 75% of colorectal tumours with RASSF2A methylation had no K-ras mutations (codons, 12 and 13) (P=0.048), Fisher's exact test). Our data demonstrate that RASSF2A is frequently inactivated in CRCs by CpG island promoter hypermethylation, and that epigenetic (RASSF2A) and genetic (K-ras) changes are mutually exclusive and provide alternative pathways for affecting Ras signalling. 相似文献
929.
Jones RL Fisher C Al-Muderis O Judson IR 《European journal of cancer (Oxford, England : 1990)》2005,41(18):2853-2860
Liposarcoma is one of the most common soft tissue sarcomas and has a number of different subtypes: well-differentiated; dedifferentiated; myxoid/round cell; and pleomorphic. However, the response of these subgroups to chemotherapy is not well documented. In this study, we have conducted a retrospective analysis of a prospectively maintained database of soft tissue sarcoma patients treated at the Royal Marsden Hospital. Eighty-eight liposarcoma patients who received chemotherapy between August 1989 and June 2004 were identified. The response rates to chemotherapy of the different histological subtypes and overall and progression free survival were investigated. Survival according to histological grade was also assessed. A statistically significant higher response rate to first-line chemotherapy was observed in patients with myxoid liposarcoma compared to de- and well-differentiated tumours, 48% (95%CI; 28–69) and 11% (95%CI; 2–29), P = 0.005. Similarly, those with myxoid liposarcoma had a significantly higher response rate compared to all other liposarcoma patients, 48% (95%CI; 28–69) and 18% (95%CI; 8–31). Patients with lower grade tumours had better overall survival. This retrospective analysis suggests that myxoid liposarcoma is relatively chemosensitive in comparison to a combination of other liposarcomas, and in particular de- and well-differentiated tumours. Further confirmation of these results should be sought by similar analyses of other databases. 相似文献
930.
Thewes B Meiser B Duric VM Stockler MR Taylor A Stuart-Harris R Links M Wilcken N McLachlan SA Phillips KA Beith J Boyle F Friedlander ML 《The lancet oncology》2005,6(8):581-588
BACKGROUND: Adjuvant endocrine therapies such as tamoxifen, goserelin, and oophorectomy improve survival for premenopausal women diagnosed with early-stage breast cancer. However, these treatments often result in menopausal symptoms, sexual dysfunction, permanent infertility, or the need to delay pregnancy. We aimed to quantify the survival gains that premenopausal patients with early-stage breast cancer require to justify the side-effects and inconvenience of adjuvant endocrine treatments. METHODS: Participants consisted of 102 women who had been diagnosed with early-stage (stage I-II) breast cancer 6-60 months previously, who were aged 40 years or younger at diagnosis, and who had been treated for a minimum of 3 months with endocrine therapy (67 with tamoxifen alone, seven with goserelin alone, and 28 with tamoxifen and goserelin or oophorectomy). 76 patients also received chemotherapy, and 75 received radiotherapy. Participants attended a face-to-face patient-preference interview, in which they were presented with four hypothetical clinical scenarios that were used to quantify the gains in survival rate and life expectancy that women judged necessary to make their endocrine therapy worthwhile. They also completed a questionnaire on standard psychological measures. FINDINGS: About half of participants thought that adjuvant endocrine therapy was worthwhile for an absolute gain in survival of 2% from a baseline of either 65% or 85%, and for a gain in life expectancy of 3 months from a baseline of 5 years and of 6 months for a baseline of 15 years. Women who had had more severe endocrine side-effects required larger gains to make endocrine therapy worthwhile (univariate p=0.02, multivariate p=0.04). INTERPRETATION: Modest gains in survival are sufficient to make adjuvant endocrine treatment worthwhile for premenopausal women with early-stage breast cancer. Knowing and incorporating what women think should enhance shared decision-making. 相似文献