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排序方式: 共有4763条查询结果,搜索用时 15 毫秒
51.
Lai Fong Chiu Philip Heywood Joanne Jordan Patricia McKinney Tony Dowell 《Critical public health》1999,9(1):5-22
Studies of minority ethnic women and cancer screening have, in the past, suffered from many theoretical and methodological weaknesses. In addition, no attempts have been made to study the complexity of the issue involved in the intercultural context, or the possible contribution of women's experiences to low uptake rates. In order to further our understanding of the issues, an alternative approach, participatory action research (PAR), was adopted to identify factors that might have contributed to the persistently low participation of minority ethnic women in the cervical screening programme, and address them collaboratively. This paper presents the key findings of the ‘problem identification' phase of the project. Using mainly the focus-group method, it explores both smear takers' and minority ethnic women's perceptions and experiences of cervical screening. Data suggest that there was a divergence in perceptions held by these groups regarding cervical screening, which contributed to negative experiences for both groups. There is also clear evidence of dysfunctional clinical communication arising from these differing perceptions. Opportunistic screening at post-natal examination adopted by many general practices appeared to have perpetuated the perceptions that the majority of minority ethnic women held about the purpose of the smear test. Compounded by language differences, the majority of women who had undergone smear testing understood neither the purpose of screening programme nor the procedure of the test. This has clear implications for promoting regular uptake, and more importantly for informed consent and choice. 相似文献
52.
53.
The clinical and radiographic results of Chiari osteotomy and shelf augmentation for acetabular dysplasia in 30 hips were reported. The average age at operation was 17 years for Chiari osteotomy and 13.8 years for shelf augmentation. The mean follow-up was 7.1 years for Chiari osteotomy and 4.1 years for shelf augmentation. Of the 14 Chiari osteotomies, 12 had good results by Tonnis clinical grading and 2 had poor results. There were significant improvements in the radiographic parameters measured (p < 0.01). They included center-edge angle of Wiberg, the acetabular angle of Sharp, the percentage of femoral head coverage, and the "c/b" ratio. For the 16 shelf augmentations, there were 8 good, 2 fair, and 6 poor results. The radiographic parameters measured were also all significantly improved (p < 0.01). The final Severin grading of the hips were improved by both Chiari osteotomy and shelf augmentation. 相似文献
54.
Stephen F Stanziale Henrik Petrowsky Prasad S Adusumilli Leah Ben-Porat Mithat Gonen Yuman Fong 《Clinical cancer research》2004,10(9):3225-3232
PURPOSE: The antitumor efficacy of a herpes simplex virus (HSV)-1 oncolytic virus depends on the cytotoxic effect of the virus, but also on viral replication and spread within the tumor. Apoptosis is considered a defense mechanism of infected cells that minimizes the spread of viral progeny by limiting cellular production of virus. We sought to determine whether oncolytic HSV-1 infection induces apoptosis in neighboring, uninfected cells and whether manipulation of apoptosis can increase viral replication and cytotoxicity. EXPERIMENTAL DESIGN: NV1066 is an oncolytic HSV-1 mutant that contains the marker gene for enhanced green fluorescent protein. OCUM human gastric cancer cells were infected with NV1066 in vitro and inspected for apoptosis by Hoechst and terminal deoxynucleotidyltransferase-mediated nick end labeling staining and for infection by expression of green fluorescence. RESULTS: A significant increase in apoptosis was seen in cells infected by NV1066. More interestingly, a significant percentage (10%) of uninfected cells also proceeded to apoptosis. After NV1066 infection, cells were also treated with N-acetylcysteine (NAC), an inhibitor of apoptosis. By day 4 after infection, 2.7x more NV1066 was produced in cells exposed to NAC than in those not exposed to NV1066 (P = 0.04). NAC also increased tumor kill when administered with virus. CONCLUSIONS: These data suggest that NV1066 induces apoptosis in uninfected cocultured cells, potentially hindering propagation of viral progeny and concomitant tumor kill. Inhibition of apoptosis may improve the efficacy of oncolytic HSV-1 therapy. 相似文献
55.
56.
Richard J Wong Mei-Ki Chan Zhenkun Yu Ronald A Ghossein Ivan Ngai Prasad S Adusumilli Brendon M Stiles Jatin P Shah Bhuvanesh Singh Yuman Fong 《Clinical cancer research》2004,10(13):4509-4516
PURPOSE: Oncolytic herpes simplex viruses (HSVs) may have significant antitumor effects resulting from the direct lysis of cancer cells. HSVs may also be used to express inserted transgenes to exploit additional therapeutic strategies. The ability of an interleukin (IL)-12-expressing HSV to treat squamous cell carcinoma (SCC) by inhibition of tumor angiogenesis is investigated in this study. EXPERIMENTAL DESIGN: A replication-competent, attenuated, oncolytic HSV carrying the murine IL-12 gene (NV1042), its non-cytokine-carrying analog (NV1023), or saline was used to treat established murine SCC flank tumors by intratumoral injection. The expression of secondary antiangiogenic mediators was measured. Angiogenesis inhibition was assessed by in vivo Matrigel plug assays, flank tumor subdermal vascularity, and in vitro endothelial cell tubule formation assay. RESULTS: Intratumoral injections of NV1042 (2 x 10(7) plaque-forming units) into murine SCC VII flank tumors resulted in smaller tumor volumes as compared with NV1023 or saline. IL-12 and IFN-gamma expression in tumors was 440 and 2.2 pg/mg, respectively, at 24 h after NV1042 injection, but both IL-12 and IFN-gamma were undetectable (<0.2 pg/mg) after NV1023 or saline injections. Expression of two antiangiogenesis mediators, monokine induced by IFN-gamma and IFN-inducible protein 10, was elevated after NV1042 treatment. Matrigel plug assays of NV1042-transfected SCC VII tumor cells demonstrated significantly decreased hemoglobin content and microvessel density as compared with NV1023 and PBS. Excised murine flank tumors treated with NV1042 had decreased subdermal vascularity as compared with NV1023 and PBS. Both splenocytes and IL-12 expression by NV1042 were required for in vitro inhibition of endothelial tubule formation. CONCLUSIONS: IL-12 expression by an oncolytic herpes virus enhances therapy of SCC through antiangiogenic mechanisms. Strategies combining HSV oncolysis with angiogenesis inhibition merit further investigation for potential clinical application. 相似文献
57.
Regional muramyl tripeptide phosphatidylethanolamine administration enhances hepatic immune function and tumor surveillance 总被引:4,自引:0,他引:4
BACKGROUND: Immune status of the liver may affect growth of liver metastases. We analyzed the ability of muramyl tripeptide phosphatidylethanolamine (MTP-PE), an immunomodulatory bacterial cell wall analog, to stimulate Kupffer cells (KCs) and protect against tumor growth, with or without an immunosuppressive partial hepatectomy (PH). Impact of MTP-PE's route of administration on KC function was assessed. METHODS: Buffalo rats (n = 7 to 12/group) were treated with saline, 40 microg MTP-PE intraportally (portal) or intravenously (IV) and challenged with 5 x 10(5) hepatoma cells, and tumors counted on day 21. To assess MTP-PE's impact on KC stimulation in animals undergoing PH, a known stimulant of tumor cell growth, groups were treated with saline or MTP-PE and challenged with tumor and underwent 30% PH. KCs were harvested and analyzed for superoxide production. Statistical analysis was performed with Mann-Whitney U test or chi-square test. RESULTS: MTP-PE-treated animals had fewer tumor nodules than control animals (19 vs 184, P <.005). MTP-PE-portal animals had fewer nodules than MTP-PE-IV (2 vs 36, P <.05). MTP-PE treatment before PH resulted in fewer tumor nodules compared with control animals (192 vs 276, P <. 05). MTP-PE administration increased macrophage superoxide production (20.6 +/- 2 vs 11.9 +/- 1.1 nmol/10(6) cells, P <.005). CONCLUSIONS: MTP-PE improved KC function and decreased growth of microscopic tumor cells. MTP-PE's effects persist after an immunosuppressive hepatectomy. Portal administration was the most effective. MTP-PE administration may be useful as a neoadjuvant therapy for patients undergoing resection of liver malignancies. 相似文献
58.
Previous work has shown that sustained increased and decreased cell
proliferation, induced by dietary zinc deficiency and caloric restriction
respectively, influence the course of N- nitrosomethylbenzylamine
(NMBA)-induced esophageal carcinogenesis in rats. The present study
considered whether the increased cell proliferation and esophageal tumor
incidence induced by zinc deficiency are reversed upon zinc replenishment.
Weanling rats were maintained initially on a deficient diet containing 4
p.p.m. zinc. After 5 weeks, carcinogen-treated animals were given six
intragastric doses of NMBA (2 mg/kg twice weekly). Controls were untreated.
After the second NMBA dose, the rats were divided into three dietary
groups. One group was continued on the deficient diet, while the other two
groups were switched to diets containing either 75 or 200 p.p.m. zinc, with
half of the members in each group fed ad libitum and half pair-fed with
deficient rats. NMBA-untreated controls were similarly replenished. At
various time points, esophageal cell proliferation was assessed in five
animals from each group by immunohistochemical detection of cells in S
phase, with in vivo 5-bromo-2'deoxyuridine labeling. At 11 weeks after the
first dose, esophageal tumor incidence was greatly reduced, from 100% in
the deficient group to 26 and 14% respectively in the replenished groups
fed ad libitum 75 and 200 p.p.m. zinc and to 14 and 11% respectively in the
replenished groups pair-fed 75 and 200 p.p.m. zinc. In addition, the number
of tumors per esophagus was reduced from 9.93 +/- 4.25 in deficient rats,
to a range of 0.11 +/- 0.31-0.30 +/- 0.54 in replenished animals. Following
zinc replenishment, esophageal cell proliferation, as measured by labeling
index (LI), the number of labeled cells and the total number of cells, was
markedly decreased in NMBA-untreated and -treated esophagi as compared with
those in corresponding deficient esophagi. Thus, the esophageal cell
proliferation induced by zinc deficiency is reversed by zinc replenishment
and replenished animals have a markedly lower incidence of esophageal
tumors.
相似文献
59.
60.
金银花药材中抗呼吸道病毒感染的咖啡酰奎宁酸类成分的定量研究 总被引:7,自引:3,他引:7
目的:寻找金银花中的抗呼吸道病毒感染的成分,并进行定量研究。方法:采用各种柱层析和制备薄层层析等方法分离、细胞病变法进行抗病毒作用的研究,采用RP-HPLC方法进行定量方法的研究。结果:分离得到了13种咖啡酰奎宁酸类化合物和咖啡酸、咖啡酸甲酯,确认咖啡酰奎宁酸类成分具有较强的抗呼吸道病毒作用,并采用HPLC方法测定了金银花中的 6种咖啡酰奎宁酸类成分和咖啡酸的含量。结论:咖啡酰奎宁酸类成分为金银花中的有效成分,定量方法准确、重复性好。 相似文献