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41.
Harry T. Whelan Lucy H. Kras Kutlan Ozker Dawn Bajic Meic H. Schmidt Yu Liu Lisa Ann Trembath Fusun Uzum Glenn A. Meyer Annette D. Segura B. David Collier 《Journal of neuro-oncology》1994,22(1):7-13
The use of PHOTOFRIN for photodynamic therapy of human gliomas has been studied by i.v. administration and laser photosensitization. Defining the uptake of PHOTOFRIN in the patient's tumor in comparison with the surrounding normal brain tissue is highly desirable for patient selection and study ofin vivo kinetics. We utilized a non-invasive approach to the detection of PHOTOFRIN uptake in brain tumors with111In-oxine radiolabeled PHOTOFRIN and external imaging and quantitation using a gamma camera. Biodistribution of111In-labeled PHOTOFRIN in 13 organs was determined in four dogs and 15 mice with gliomas.99mTc-DTPA was used as a control for nonspecific uptake. The greatest concentration of111In-PHOTOFRIN in the brain tumor occurred at 24 hours post i.v. administration. The brain tumor PHOTOFRIN uptake was seven times greater than that of normal brain. The decreased blood background at 72 hours made this the optimum time for imaging. Specific tumor tissue uptake of111In-PHOTOFRIN occurred, well beyond that resulting from blood-brain-barrier (BBB) breakdown. 相似文献
42.
O Y Tanaka M I Nemes H M Novaes M G Bastos C L Cesar L F Riedel 《Revista de saúde pública》1999,33(3):219-229
In Brazil, in recent years, as a result of the increasing participation of county authorities in health care, a need for tools which would contribute to the better preparation of local administrators, complementary to the activities of a more academic nature, has been recognized. One of the possible alternatives is the exploitation of experiences, regarded as successful, in local health care planning and administration, by using them as material for "case studies" in activities with selected groups of health care administrators thus, stimulating the identification of those elements which contributed to the favorable results attained, and their interactions, in the quest for analogies which would facilitate the identification of new perspectives for their own situations. In this article an experience of a "case studies" development, in response to a demand from UNICEF, based on 8 counties in from the North and Northeast, which were successful in using a "focus approach" in their organization of data and their utilisation in a seminar with 21 local managers from both regions, is presented. During the seminar the local health managers attained greater knowledge of the strategies implemented and identified feasible intervention alternatives. The methodological proposition of teaching on the basis of case studies, using a conceptual strategy of grouping experiences according to specific dimensions enabled local health managers to learn from their practical experiences. 相似文献
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Fernandez E Schiaffino A La Vecchia C Borrás JM Nebot M Saltó E Tresserras R Rajmil L Villalbí JR Segura A 《Preventive medicine》1999,28(4):361-366
BACKGROUND: Few studies have investigated the association between age at starting smoking and the average number of cigarettes smoked per day in adulthood. To provide further evidence on this issue, we analyzed data from the Catalan Health Interview Survey (CHIS). METHODS: The CHIS was conducted in 1994 on a randomly selected sample (N = 15,000) of the population of Catalonia, Spain. A total of 4,897 current or exsmokers (3,276 males and 1,621 females) were included for analysis. Age-standardized proportions of subjects smoking <15, 15-24, and >/=25 cigarettes/day, age-standardized mean number of cigarettes smoked per day, and multivariate odds ratios (OR) of being a heavy smoker (>/=25 cigarettes/day) according to age at starting smoking (<15, 15-17, 18-19, >/=20 years) were computed. RESULTS: Men who started smoking before the age of 15 smoked on average 5.5 cigarettes more than those who started at age 19 or over. Women who started smoking early in life smoked, on average, 6.8 cigarettes/day more than women who started later. The proportion of smokers of <15 cigarettes/day was higher among subjects who started smoking later. Both for males and for females, the OR of being a heavy smoker significantly increased with decreasing age at starting smoking (OR = 2.4 for males and 4.5 for females who started at age <15 versus >/=20 years). The level of education did not modify the relationship in males, whereas the association with age at starting was only apparent for more educated women. CONCLUSIONS: This study confirms that age at starting smoking is inversely and strongly associated to the number of cigarettes smoked per day. Thus, actions aimed at the prevention or delay of smoking onset among adolescents would have an important beneficial effect. 相似文献
44.
E. Fernandez A. Schiaffino L. Rajmil X. Badia A. Segura 《Journal of epidemiology and community health》1999,53(4):218-222
BACKGROUND AND OBJECTIVES: While socio-economically derived differences in health and health services use have long been a subject of study, differences based on gender, considered as the explicative variable, have scarcely been quantified from population-based data. The aim of this investigation was to analyse inequalities in health and health care services utilisation between men and women in Catalonia (Spain). DESIGN, SETTING, PARTICIPANTS, AND MEASURES: Data from the Catalan Health Interview Survey, a cross sectional survey conducted in 1994, were used. A total of 6604 women and 5641 men aged 15 years or over were included for analysis. Health related variables studied were self perceived health, restriction of activity (past two weeks), and presence of chronic conditions; health services use variables analysed were having visited a health professional (past two weeks), an optometrist (12 months), or a dentist (12 months); and hospitalisation (past 12 months). Age standardised proportions were computed according to gender, and prevalence odds ratios (OR) were derived from logistic regression equations. MAIN RESULTS: Women more frequently rated their health as fair or poor than men (29.8% v 21.4%; OR = 1.22; 95% CI: 1.10, 1.34). More women than men reported having restricted activity days (OR = 1.86; 95% CI: 1.59, 2.18) and chronic conditions (OR = 1.74; 95% CI: 1.60, 1.89). The proportion of women visiting a health professional was slightly greater than that for men (OR = 1.20; 95% CI: 1.09, 1.31), as was the proportion of women visiting an optometrist (OR = 1.21; 95% CI: 1.11, 1.33), and a dentist (OR = 1.43; 95% CI: 1.31, 1.55). The proportion of hospitalisation was lower in women (6.6%) than in men (7.7%; OR = 0.73; 95% CI: 0.63, 0.85). When health services use was analysed according to self perceived health, women declaring good health reported a greater probability of consulting a health professional (OR = 1.35; 95% CI: 1.20, 1.52). There were no differences in respect to hospitalisation, visits to the optometrist and to the dentist. CONCLUSIONS: These results indicate a pattern close to the inverse care law, as women, who express a lower level of health and thus would need more health care, are not, however, using health services more frequently than men. 相似文献
45.
The purpose of this study was to compare the fracture resistance of four posterior restorations involving an entire cusp replacement. Four groups were established, each containing eight caries-free mandibular molars, similar in size and anatomic form. A mesio-occlusal preparation including the lingual cusp was prepared on all teeth. Group A were restored with a pin-retained amalgam. Group B were restored with amalgam and a meta adhesive. Group C were restored with a composite resin with a beta-glass quartz insert. Group D were restored with composite resin and a HEMA adhesive. All specimens were mounted in acrylic and stored in artificial saliva for 30 days. Each specimen was loaded in compression at a 90 degrees angle in an Instron testing machine with a crosshead speed of 0.5 cm/min. Results demonstrated the mean (SD) failure loads in kilograms for each group to be: A, 1155 (388); B, 1232 (436); C, 1345 (375); D, 1595 (373). Analysis of variance indicated no significant difference among groups at P<0.05. Although the values for the composite resin restoration with the adhesive were higher than the other restorative techniques. 相似文献
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Ashok N. Kukadia Cesar J. Ercole Paul Gleich Hugh Hensleigh Jon L. Pryor 《The Journal of urology》1996,156(5):1643-1646