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171.
L. L. Williams H. M. Lew F. H. Davidorf S. G. Pelok C. T. Singley J. S. Wolinsky 《Archives of virology》1994,134(3-4):379-392
Summary Persistent infection with rubella virus (RV) can alter secondary functions of host cells. Previously we had documented defective phagocytosis of latex beads by cultured human retinal pigment epithelial cells (RPE), persistently infected with M-33 RV (RPE/RV). Here, examining possible mechanisms for altered function, we reported significant differences between the total esterified fatty acids (FA) of RPE and RPE/RV membranes, measured by gas liquid chromatography. RPE/RV contained an increased proportion of saturated FA, particularly palmitic acid, with a presence of unusual chromatographic FA peaks co-eluting with odd-numbered long-chain carbon atom FA not normally found in human cells. Apical membrane microvilli, structures essential to phagocytic activity of RPE and RPE/RV, observed by scanning and transmission electron microscopy, were similar in number and appearance between uninfected RPE and RPE/RV cells before and after latex bead addition. However, RPE/RV microvilli, possibly reflecting altered membrane FA composition, engaged latex beads less effectively than uninfected RPE microvilli. In addition, microvilli remained abnormally distributed on RPE/RV cell surfaces at 48 h after latex addition. Thus, RV persistent infection may affect the cellular membrane fluidity and functional activity of human cells with increased saturated FA proportions and altered FA components of membrane phospholipids. These changes may participate in the defective phagocytosis of RPE/RV. 相似文献
172.
Thyroxine replacement in post-radioiodine hypothyroidism 总被引:1,自引:0,他引:1
C. P. Bearcroft G. C. Toms S. J. Williams K. Noonan J. P. Monson 《Clinical endocrinology》1991,34(2):115-118
Thyroxine replacement dose in 70 patients with post-radioiodine (for Graves' thyrotoxicosis) hypothyroidism was compared with that in 34 patients with autoimmune hypothyroidism matched for age and sex and diagnosed during the same period. Median replacement dose in the post-radioiodine group (100 micrograms daily) was significantly lower (P = 0.006) than in the autoimmune hypothyroid group (137.5 micrograms daily). Furthermore there was marked variation in the time elapsing from onset of post-radioiodine hypothyroidism to achievement of a given maintenance dose. These findings may be explained by persistence of non-TSH mediated thyroid function, after radioiodine therapy for Graves' thyrotoxicosis. The observations indicate the potential risk of overtreatment with thyroxine in post-radioiodine hypothyroidism unless the dose is carefully titrated against serum TSH levels. Final thyroxine requirements may not be evident in the initial phase of treatment and patients with apparently low maintenance thyroxine requirements require long-term follow up. 相似文献
173.
174.
175.
Effects of race and socioeconomic status on survival of 1,332 black, hispanic, and white women with breast cancer 总被引:3,自引:0,他引:3
Dr. Luisa Franzini PhD Anna Fay Williams PhD Jack Franklin PhD S. Eva Singletary MD Richard L. Theriault DO 《Annals of surgical oncology》1997,4(2):111-118
Background: A survival disadvantage for black women with brest cancer, which persists after controlling for stage of the disease, has been reported. This study investigates the effects of race and socioeconomic status (SES) on breast cancer survival after controlling for age, stage, histology, and type of treatment.
Methods: Kaplan-Meier and Cox proportional hazards models were used to analyze the interaction between race and SES in predicting survival in a sample of 163 black, 205 Hispanic, and 964 white women with breast cancer treated at M. D. Anderson Cancer Center (1987–1991).
Results: The results of univariate and multivariate analyses indicate that race was not a significant predictor of survival after adjusting for SES and other confounding factors such as demographic and disease characteristics. SES remained a significant predictor of survival after all adjustments were made. There was no evidence of differences in type of treatment by race or SES if adjustments were made for stage.
Conclusions: These results suggest that institutional factors, such as access to treatment, do not explain survival differences by race or SES. Other factors associated with low SES, such as life-style and behavior, may affect survival. 相似文献
176.
J H Williams T J Drinka J R Greenberg J Farrell-Holtan R Euhardy M Schram 《The Gerontologist》1991,31(1):84-91
The Assessment of Living Skills and Resources (ALSAR), an innovative instrumental activities of daily living tool, systematically evaluates the accomplishment of 11 tasks by separately rating patient skill and resource levels for each task and combining these levels to determine risk. The ALSAR was administered to 75 elderly veterans in a home care program. It predicted change to more supportive living arrangements and a more structured living environment, nursing home placement, hospitalization, and death during the 6-month study period. The ALSAR has proven useful for interdisciplinary problem solving and treatment planning. 相似文献
177.
This paper reviews orthodontic care in patients who are in non-traditional categories. Specific orthodontic management of a patient who had severe hemophilia, seropositivity for anti-HIV Ab, and Hepatitis B surface antigen is reviewed. The Importance of defining acceptable treatment goals in these patients is of paramount Importance. 相似文献
178.
We reviewed the results following trabeculodialysis in 25 eyes of 22 patients with secondary glaucoma due to chronic anterior uveitis. After 1 year, intraocular pressure (IOP) was uncontrolled (greater than 21 mm Hg) in 11 eyes (44%). Trabeculodialysis controlled IOP (less than 21 mm Hg) in 14 eyes (56%), with an average follow up of 52 months (range, 12 to 151 months). Sixteen eyes (64%) were aphakic, but did no worse than the phakic eyes. One eye developed a subchoroidal hemorrhage 3 days postoperatively which required drainage. No other serious complications were encountered. Trabeculodialysis is a safe procedure which can achieve pressure control in these difficult eyes. 相似文献
179.
Pharmacokinetic parameters of third generation cephalosporins vary widely, requiring different dosage regimens and adjustment methods for each agent. Although their antibacterial spectrum favours their usage in infections caused by aerobic Gram-negative organisms, due to their limited post-antibiotic effect against these organisms, dosage regimens should ensure that free drug concentrations at the site of infection remain above the minimum inhibitory concentration for as much of the dosage interval as possible in patients with normal host defence mechanisms and for the entire dosage interval in immunocompromised patients. Altered protein binding encountered in various disease states can affect both microbiological and pharmacokinetic properties especially for drugs with high protein binding. Since the concentrations at the site of action are often different from those in serum, a higher or lower range of dosages needs to be selected depending on the target site. Decreased renal function affects the elimination of most third generation cephalosporins, whereas the presence of hepatic disease does not generally necessitate dosage adjustment. Because of the complex age-related physiological changes in paediatric and elderly patients, dosage should be adjusted on the basis of the reported pharmacokinetic data in these populations. The usual recommended dose may or may not be optimal in a given condition depending on the complex interactions between pharmacokinetic, microbiological and other host factors. 相似文献