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11.
Li Li Alice C Jiang Pin Dong Yi Wan Zi Wei Yu 《Otolaryngology--head and neck surgery》2007,137(4):659-664
OBJECTIVE: To investigate the characteristics of Hep-2 cell with multidrug resistance (MDR) induced by Taxol. STUDY DESIGN: Hep-2 cells were exposed in stepwise escalating concentration of Taxol to develop the resistant cell line-Hep-2T. Cell cycle distribution, apoptosis, and rhodamine accumulation were studied through flow cytometry. The MDR1 and MRP1 genes were detected through real-time quantitative RT-PCR, and the corresponding proteins were detected through Western blotting. RESULTS: The drug resistance of Hep-2T cells to Taxol, doxorubicin, gemcitabine, 5-FU, and cisplatin all increased. The percentage of G0/G1 phase and the antiapoptosis ability increased significantly compared with Hep-2 cells. Both MDR1 and MRP1 also increased at gene and protein level, though MDR1 was more prominent. CONCLUSION: More emphasis should be laid on MDR1/Pgp, the non-Pgp substrate chemotherapeutic agents, and the changes of cell cycle distribution to prevent MDR induced by Taxol. SIGNIFICANCE: These findings may provide theoretical support for the reverse of MDR. 相似文献
12.
Empty Sella and Headache 总被引:2,自引:0,他引:2
Teresa Catarci Fabrizio Fiacco Luigi Bozzao Manuela Pati Alice Valeria Magiar Rosanna Cerbo 《Headache》1994,34(10):583-586
SYNOPSIS
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology. 相似文献
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology. 相似文献
13.
OBJECTIVES: To evaluate the application of a translated version of an established self-administered questionnaire for carpal tunnel syndrome on Chinese patients in Hong Kong. DESIGN: Evaluation of an instrument tool. SETTING: Department of Orthopaedics and Traumatology, Queen Mary Hospital, Hong Kong; Holistic Medical Centre, Aberdeen, Hong Kong. PARTICIPANTS: Patients with carpal tunnel syndrome, translators. MAIN OUTCOME MEASURES: The adaptation was based on forward-backward translation from English to Chinese (Hong Kong) and vice versa. Meetings with translators, investigators, and patients were organised to generate an acceptable version of the questionnaire. A pilot study was carried out on 20 patients and subsequently minor adjustments were added. Fifty patients were recruited to validate the reliability and internal consistency of the questionnaire. RESULTS: The ordinality of response agreed with the original instrument. Test-retest reproducibility showed no significant difference between tests. The Pearson correlation coefficient ranged from 0.83 to 0.93. Internal consistency was good, at 0.85. CONCLUSION: Through the validation of the Hong Kong Chinese version of the questionnaire, we are able to produce an assessment tool for the local patients. Furthermore, we are able to create a platform for: (i) a cross-national and cross-cultural epidemiological comparison as well as a means of (ii) evaluating different types of treatments. 相似文献
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16.
Alice J Hausman Ph.D. M.P.H. Howard Spivak M.D. Deborah Prothrow-Stith M.D. James Roeber M.S. 《The Journal of adolescent health》1992,13(8):668-675
This paper describes the implementation of a community-based youth violence prevention project that utilized an educational curriculum and a mass media campaign. The extent of penetration of the intervention into target areas and the degree of contamination of control areas are assessed, and the most frequently contacted forms of educational outreach are identified. Two sources of data, provider interviews and a random digit dialed telephone survey, were used to track the source and extent of teens' exposure to the intervention. Agency provider data revealed that 40% of the 92 contacted agencies actually conducted violence prevention education, reaching 22% of the target area teens. Approximately one-half of the surveyed teens reported some exposure to the program, with 13% of the teens in target areas reporting participation in interactive educational activities associated with the project. The most common source of exposure was the media campaign. Most teens report a single exposure, usually to the media campaign, although 29% report contact with more than one form of violence prevention education. While the project did not achieve community saturation, the data show that the community-based model of intervention for violence prevention is feasible and effective in reaching teenagers. This research highlights some difficulties in evaluating prevention programs, including reconciling community ownership with project identification, the ethics of curtailing services for control purposes, and factors influencing recall of participation. 相似文献
17.
Comparison of hand-sewn and stapled esophagogastric anastomosis after esophageal resection for cancer: a prospective randomized controlled trial. 总被引:14,自引:0,他引:14
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OBJECTIVE: The objective of this study was to compare the hand-sewn and stapled methods in esophagogastric anastomosis. SUMMARY BACKGROUND DATA: After esophageal resection for cancer, the relative merits of the hand-sewn and the stapled methods of esophagogastric anastomosis, especially regarding leakage and stricture rates, have not adequately been studied. METHODS: A prospective randomized controlled trial was undertaken in 122 patients with squamous cell cancer of the thoracic esophagus who underwent a Lewis-Tanner esophagectomy. Patients were stratified according to esophageal size, based on the diameter of the divided esophagus (< or > or = 30 mm) and then were randomized to have either a hand-sewn or a stapled anastomosis. RESULTS: The mean total operating times (standard error of the mean) when the hand-sewn and the stapled methods were used were 214 (4) minutes and 217 (3.4) minutes, respectively (p = not significant [NS]). The respective in vivo proximal resection margins (standard error of the mean) were 8 (0.4) cm and 7.6 (0.4) cm (p = NS). Leakage rates were 1.6% and 4.9% (p = NS). Excluding hospital deaths, patients with leakage or anastomotic recurrence, and those who received radiation therapy to histologically infiltrated resection margin, anastomotic stricture was found in 5 (9.1%) of 55 patients in the hand-sewn group and 20 (40%) of 50 in the stapler group (p = 0.0003). The difference in stricture rates was significant in small as well as large esophagi. Anastomotic recurrence developed in only one patient in each group. CONCLUSIONS: The authors conclude that both methods were safe, but the stapled technique resulted in more stricture formation. 相似文献
18.
Proximal gastric vagotomy. The preferred operation for perforations in acute duodenal ulcer. 总被引:1,自引:0,他引:1
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J Boey F J Branicki T T Alagaratnam P J Fok S Choi A Poon J Wong 《Annals of surgery》1988,208(2):169-174
Simple closure, the conventional operation for perforated acute duodenal ulcers, is associated with symptomatic relapse in a large proportion of patients. In order to assess the role of immediate definitive surgery, 78 fit patients with perforated acute ulcers were prospectively randomized to undergo either closure alone or proximal gastric vagotomy with closure (PGV). Patients taking potentially ulcerogenic drugs or who had severe stress were excluded from the study. Both groups were comparable with respect to age, sex, general medical health, duration of perforation, length of ulcer history, and presence of duodenal scarring. There was no hospital mortality. Minor complications occurred in 7.3% after closure and 10.8% after PGV. At 3 years follow-up, the cumulative recurrence rates were 36.6% and 10.6% after closure and PGV, respectively (p = 0.001). Eighty-five per cent of recurrences after closure were symptomatic, and half of them required reoperation. Duodenal scarring itself did not appear to influence the outcome after closure. PGV was not associated with dumping, diarrhea or other unwanted side effects. Although less than that in chronic ulcers, there is a substantial risk of symptomatic relapse after closure of perforated acute duodenal ulcers. With judicious patient selection, PGV effectively reduces this risk without incurring disabling side effects associated with other ulcer operations. 相似文献
19.
Impaired cortisol stress response in fish from environments polluted by PAHs,PCBs, and mercury 总被引:6,自引:0,他引:6
Alice Hontela Joseph B. Rasmussen Céline Audet Gaston Chevalier 《Archives of environmental contamination and toxicology》1992,22(3):278-283
The cortisol stress response to capture was investigated in two species of fish (Perca flavescens and Esox lucius) from sites polluted by high levels of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and mercury, and from reference sites in the St. Lawrence river system. Fish from the reference sites exhibited the normal elevation of serum cortisol in response to the acute stress of capture and had large pituitary corticotropes. In contrast, fish from the most polluted sites were unable to increase their serum cortisol in response to the acute stress of capture and their pituitary corticotropes were atrophied. These results suggest that a life-long exposure to chemical pollutants may lead to an exhaustion of the cortisol-producing endocrine system, possibly as a result of prolonged hyperactivity of the system. 相似文献
20.
ABSTRACT: This paper reports on the effectiveness of a teacher development project in promoting implementation of a comprehensive school health education curriculum among inner city elementary school teachers. The longitudinal evaluation design provides empirical data on the efficacy of a strategy to reduce teachers' concerns and promote use of the curriculum at the classroom level. Data were collected at various points throughout the project period from 156 school staff from five schools. Results from analyses of repeated measures of teachers' feelings of preparedness to teach specific health topics, and the observed relationship between both high and improved feelings of preparation and reported health teaching suggest that teacher development efforts including training and ongoing reinforcement to increase teachers' feelings of preparedness can have significant classroom effects. 相似文献