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31.
32.
An Australian study of functional status after childbirth 总被引:1,自引:0,他引:1
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34.
Mutation of the p53 tumor suppressor gene in spontaneously occurring osteosarcomas of the dog 总被引:8,自引:0,他引:8
Inactivation of the p53 tumor suppressor gene has been implicated in the
pathogenesis of numerous human cancers, including osteosarcomas.
Appendicular osteosarcomas of the dog appear to be a good model for their
human equivalent with regard to biologic behavior, epidemiology and
histopathology. We individually screened exons 5-8 of the p53 gene for
mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to
compare the role of this gene in human and canine osteosarcoma
tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with
one tumor possessing two mutations within different exons. Of these, seven
were missense mutations and the eighth was a 'silent' mutation potentially
affecting the exon 6-7 splicing region. Five of the missense mutations were
located in highly conserved regions IV and V, while another corresponded
with the highly conserved codon 220 mutational hotspot located outside the
conserved domains. The locations and types of mutations were nearly
identical to those reported in human cancer. These findings provide strong
evidence of the involvement of p53 mutations in the development of canine
appendicular osteosarcomas. Canine osteosarcomas appear to be a promising
model for their human equivalent on a clinical, pathologic, and molecular
level.
相似文献
35.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
36.
Perspectives on colorectal cancer screening: a focus group study 总被引:3,自引:0,他引:3
Vivek Goel MD MSc FRCPC Ross Gray PhD Pam Chart MD CM Marg Fitch RN PhD Fred Saibil MD FRCPC Yola Zdanowicz MA 《Health expectations》2004,7(1):51-60
Objective To assess attitudes and acceptability of Ontario consumers and doctors towards colorectal screening with faecal occult blood testing (FOBT) and colonoscopy. Design, setting and participants Focus groups with gender‐specific samples of the population, high‐risk gastroenterology patients and family doctors. Method Semi‐structured interview guides used by facilitator to lead groups through knowledge of risk factors and prevention of colorectal cancer, the screening modalities, requirements for implementing screening programmes, barriers to screening and preferences towards screening. Main findings There were low levels of knowledge about colorectal cancer and its prevention in the general population. FOBT was an acceptable screening modality, but considerable education about its use and benefits would be necessary to implement a screening programme. Colonoscopy was not perceived to be a good choice for a primary screen in the general population. The high‐risk group supported use of FOBT in the general population and emphasized the need for education. The doctors were more reluctant about screening, requesting clear guidelines. They also identified the time and resources that would be required if a screening programme were initiated. Conclusion While colorectal screening is acceptable in this sample, information and decision aids are required to enable consumers and providers to make effective decisions. Implementation of colorectal screening programmes requires substantial educational efforts for both consumers and doctors. 相似文献
37.
38.
氯地滴眼液的含量测定 总被引:4,自引:0,他引:4
目的:采用HPLC法测定氯地滴眼液中氯霉素和地塞米松磷酸钠的含量。方法:色谱分析条件:ODS柱作分析柱,流动相为甲醇/水体系,0 ̄8min使用40%甲醇,8 ̄16min使用60%甲醇,流速1ml/min,0 ̄9min240nm紫外检测,:二组分分离良好。各组各组性关系良好,平均回收率氯霉素99.8%(RSD=1.2%,n=5),地塞米松磷酸钠99.4%(RSD=0.7%,n=5),结论:该法用于氯 相似文献
39.
Singapore Indian Eye Study‐2: methodology and impact of migration on systemic and eye outcomes
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40.
A double-blind withdrawal trial in 41 chronic schizophrenic outpatients was carried out during 6 months. Depot neuroleptics (fluphenazine decanoate or flupenthixol decanoate) were compared with placebo to evaluate clinical and neurological effects during continued therapy and during withdrawal. The drugs were significantly more effective than placebo in preventing relapse and rehospitalization. In the placebo group 62% relapsed compared to 27% in the drug group. There was a weak and nonsignificant tendency to a higher relapse frequency in the flupenthixol group compared to the fluphenazine group. After withdrawal for 6 months, plasma levels for fluphenazine were detectable. Plasma levels for flupenthixol were not detectable after 9 weeks of withdrawal. The differences in the plasma levels may possibly explain the difference in relapse rate between the two depot neuroleptics. Furthermore, it was found that the patients who relapsed during fluphenazine treatment had a significantly lower plasma level of the drug than patients who did not relapse during treatment. The results from this study provide some information on the therapeutic levels of fluphenazine and flupenthixol in schizophrenic patients. 相似文献