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91.
Olsen RV 《Health facilities management》1990,3(2):28, 30-21, 33
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In this paper a doctor acts as a perfect agent for a group of patients in an environment where the health service is funded by a group of contributors. The contributor group donates resources to the health sector in accordance with its split preferences about the health care services which they would like for themselves and those which they would like for others. We show that the size of the health budget is endogenous and depends on the choices made by the doctor. The focus is on the division of the budget between health enhancing and non-health enhancing health care. 相似文献
94.
Wheelock CE Wolfe MF Olsen H Tjeerdema RS Sowby ML 《Archives of environmental contamination and toxicology》1999,36(3):281-287
Hsp60 induction was selected as a sublethal endpoint of toxicity for Brachionus plicatilis exposed to a water accommodated fraction (WAF) of Prudhoe Bay crude oil (PBCO), a PBCO/dispersant (Corexit 9527(R)) fraction and Corexit 9527(R) alone. To examine the effect of multiple stressors, exposures modeled San Francisco Bay, where copper levels are approximately 5 microgram/L, salinity is 22 per thousand, significant oil transport and refining occurs, and petroleum releases have occurred historically. Rotifers were exposed to copper at 5 microgram/L for 24 h, followed by one of the oil/dispersant preparations for 24 h. Batch-cultured rotifers were used in this study to model wild populations instead of cysts. SDS-PAGE with Western Blotting using hsp60-specific antibodies and chemiluminescent detection were used to isolate, identify, and measure induced hsp60 as a percentage of control values. Both PBCO/dispersant and dispersant alone preparations induced significant levels of hsp60. However, hsp60 expression was reduced to that of controls at high WAF concentrations, suggesting interference with protein synthesis. Rotifers that had been preexposed to copper maintained elevated levels of hsp60 upon treatment with WAF at all concentrations. Results suggest that induction of hsp60 by chronic low-level exposure may serve as a protective mechanism against subsequent or multiple stressors and that hsp60 levels are not additive for the toxicants tested in this study, giving no dose-response relationship. The methods employed in this study could be useful for quantifying hsp60 levels in wild rotifer populations. 相似文献
95.
Tuntiseranee P Olsen J Chongsuvivatwong V Limbutara S 《Journal of epidemiology and community health》1999,53(10):624-629
STUDY OBJECTIVE: To examine the effect of socioeconomic status on pregnancy outcome in an urbanised area in a rapidly developing country. METHODS: A cohort of 1797 pregnant women who attended antenatal care clinics at the two 700 bed hospitals in Hatyai city was recruited from September 1994 to November 1995. The pregnant women were followed up from the 17th week of gestation until delivery. The socioeconomic indicators selected were family socioeconomic status, maternal education, maternal occupation, family income and work exposure characteristics based upon Karasek's job content questionnaires. Pregnancy outcomes were birth weight, low birth weight, small for gestational age and preterm delivery. MAIN RESULTS: Mean birth weight correlated with socioeconomic status and income but after adjustment for parity, maternal age and height, weight at delivery day, baby sex, obstetrical complications and antenatal care utilisation, only family income remained correlated with birth weight. No association with any socioeconomic status indicators was found when using dichotomous outcome (low birth weight, small for gestational age or preterm delivery). Only high psychological job demand was associated with small for gestational age. Confounder adjustment indicated that the observed social status differences in pregnancy outcomes were mainly attributable to mother's characteristics and antenatal service use. CONCLUSIONS: Socioeconomic indicators alone were not associated with reduced fetal growth or preterm delivery in this study, which recruited mainly lower or middle class women. Karasek's psychological job demand was only weakly correlated with small for gestational age infant. 相似文献
96.
Lymphoscintigraphy and intraoperative lymphatic mapping of sentinel lymph nodes in melanoma patients
Williams BS Hinkle GH Douthit RA Fry JP Pozderac RF Olsen JO 《Journal of nuclear medicine technology》1999,27(4):309-317
Identification of sentinel lymph nodes (SLNs) using lymphoscintigraphy, the blue dye technique and intraoperative lymphatic mapping with a gamma-detecting probe has become the standard of care in diagnosing and treating melanoma. Numerous clinical studies have proven the reliability of predicting the histology of remaining lymph nodes in the lymphatic basin from the histologic evaluation of the SLNs. Technical and clinical factors presented in this paper have been shown to increase the accuracy of localization of SLNs. The nuclear medicine technologist shares a vital role in the radiopharmaceutical preparation and administration for preoperative lymphoscintigraphy and intraoperative lymphatic mapping in patients with melanoma. 相似文献
97.
Olsen J 《Scandinavian journal of work, environment & health》1999,25(Z1):5-7; discussion 76-8
Studies of fecundity are few, and there is a need to know how fecundity develops over time and to identify its determinants. Since fecundity is best measured by studying time to pregnancy, valid and well-recognized instruments are needed for data collection. A standardized questionnaire on fecundity not only has to obtain information on waiting time, but also information on the importance of evaluation results. The use of contraceptive methods, the understanding of family planning, and behavioral changes driven by past reproductive experience are issues of importance for designing and interpreting results, as are other sources of bias also. 相似文献
98.
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100.
The most apical 2 mm of the root canals of periapically diseased roots were examined for microorganisms by scanning electron microscopy (SEM). Bacteria in this area were observed in 10 out of 12 (83.3%) cases. The two remaining cases exhibited bacteria more coronally, with tissue remnants between the bacterial front and the apical foramen. Rod-shaped bacteria dominated, but filaments, spirochetes and cocci were also seen. Cocci and rods sometimes formed micro-colonies. Occasionally, cocci were seen attached to filaments forming "corn-cob"-like structures. Deposits resembling bacterial plaque were also found inside the root canal. SEM is useful for studying microbial topography of the apical root canal. 相似文献