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991.
Chiara Riley Jack P. London John A. Burmeister 《Journal of oral pathology & medicine》1992,21(3):124-127
Two hundred HIV-positive subjects were surveyed to determine their periodontal health status. Particular attention was given to the occurrence of a severe and rapidly progressing form of periodontal disease designated "HIV-associated periodontitis", which has been reported as being unique to AIDS patients. Among the subjects comprising the cohort, 85 subjects had good gingival health, 59 subjects exhibited gingivitis, 49 cases of adult periodontitis were observed, 5 subjects presented with advance adult periodontitis, and 2 cases of necrotizing ulcerative periodontitis (NUP) were found within the group. The periodontitis of the patients in this survey did not have unique or pathognomonic characteristics which could set their periodontal disease apart from the periodontal disease seen in HIV negative population. 相似文献
992.
M F White R Morris R M Feist C D Witherspoon H A Helms G R John 《Southern medical journal》1989,82(2):151-158
Although an estimated 1 million Americans suffer ocular injuries each year, the setting of injury and its prognostic implications have not been closely examined. Using data compiled by the Eye Injury Registry of Alabama (EIRA) from 514 cases of serious eye injury, we examined the demographics and prognosis of ocular injury by setting of injury. Work-related injuries accounted for only 28% of total injuries, and injuries occurring at home accounted for 27%, followed by situations related to recreation (25%), assault (11%), travel (5%), and "other" (school, unknown, etc) (4%). The poorest initial vision, poorest final vision, and highest rate of enucleation occurred in patients injured by assault, whereas the lowest rate of enucleation and loss of light perception was found in patients who had work-related injuries. Patients in the "other" category had the highest rate of return to 20/100 or better vision. 相似文献
993.
Timothy R. DeGrado James E. Holden Chin K. Ng David M. Raffel S. John Gatley 《European journal of nuclear medicine and molecular imaging》1989,15(2):78-80
The use of 15-p-iodophenyl--methyl-pentadecanoic acid (Me-IPPA) as an indicator of long chain fatty acid (LCFA) utilization in nuclear medicine studies was evaluated in the isolated, perfused, working rat heart. Time courses of radioctivity (residue curves) were obtained following bolus injections of both Me-IPPA and its straight chain counterpart 15-p-iodophenyl-pentadecanoic acid (IPPA). IPPA kinetics clearly indicated flow independent impairment of fatty acid oxidation caused by the carnitine palmitoyltransferase I inhibitor 2[5(4-chlorophenyl)pentyl]oxirane-2-carboxylate (POCA). In contrast, Me-IPPA kinetics were insenstive to changes in fatty acid oxidation rate and net utilization of long chain fatty acid. Analysis of radiolabeled species in coronary effluent and heart homogenates showed the methylated fatty acid to be readily incorporated into complex lipids but a poor substrate for oxidation. POCA did not significatly alter metabolism of the tracer, suggesting that the tracer is poorly metabolized beyond Me-IPPA-CoA in the oxidative pathway. 相似文献
994.
The authors examined reports addressing the question of whether electroconvulsive therapy (ECT) is more effective in psychotic or nonpsychotic depressive disorders. Most ECT studies did not consider the issue directly, and those that did had varying methodologies and results. The authors then analyzed the data of 33 depressed patients to clarify the differential response to ECT in 13 psychotic and 20 nonpsychotic patients. The subjects were also examined as to type of electrode placement. ECT produced a greater reduction in Hamilton Depression Rating Scale scores in the psychotic depressives as compared to the nonpsychotics after an average of 9.2 treatments. The two patients who were nonresponders to ECT were both nonpsychotic. 相似文献
995.
Dossetor JB 《Transplantation proceedings》1989,21(1):1395-1397
996.
Pierre Lachapelle Julie Benoit John M. Little Jocelyn Faubert 《Documenta ophthalmologica. Advances in ophthalmology》1989,73(4):327-336
Of all the electroretinogram (ERG) components (a-wave, b-wave, and oscillatory potentials) only one oscillatory potential, OP2, was found to be significantly correlated with the absolute intensity of the flash stimulus (i.e., the intensity of the stimulus irrespective of the state of retinal adaptation). Our finding was further confirmed in single cell recordings of lateral geniculate unit activity in rabbits in which peak time of OP2 was found to correlate better with the geniculate activity. For these reasons we have identified OP2 as the intensity coding oscillatory potential of the ERG. In order to investigate if this new feature could have some clinical significance, we examined photopic ERGs recorded from patients affected with various retinopathies. In most instances the peak time of OP2 paralleled that of the b-wave, that is, in the ERG with delayed b-wave the peak time of OP2 was also delayed, while in ERGs with normal b-wave peak time the peak time of OP2 was also normal. However, in some conditions (especially in cone-rod diseases) a delayed OP2 was found in ERGs with normal b-wave peak times. 相似文献
997.
Donald L. Phillips James L. Pirkle Virlyn W. Burse John T. Bernert Jr. L. Omar Henderson Larry L. Needham 《Archives of environmental contamination and toxicology》1989,18(4):495-500
Twenty healthy adult humans had serum samples drawn on four occasions within a 24-hr period: after a 12 hr overnight fast, 4–5 hr after a high fat breakfast, at midafternoon, and the next morning after another 12 hr fast. Nonfasting samples had 22% to 29% higher mean concentrations (p < 0.05) than did fasting samples for polychlorinated biphenyls (PCBs, 4.81 vs 3.74 ng/g serum wt), hexachlorobenzene (HCB, 0.163 vs 0.134 ng/g serum wt), andp,p-dichlorodiphenyldichloroethylene (p,p-DDE, 6.74 vs 5.37 ng/g serum wt) measured by electron capture gas liquid chromatography. Total serum lipids were estimated from measurements of total cholesterol, free cholesterol, triglycerides, and phospholipids and were 20% higher in nonfasting samples than in fasting samples (7.05 g/L vs 5.86 g/L). When PCBs, HCB, andp,p-DDE concentrations were corrected by total serum lipids, results from fasting and nonfasting samples were not statistically different. Because of the differences in these chlorinated hydrocarbon concentrations observed with different sample collection regimens, meaningful comparison of analytical results requires standardizing collection procedures or correcting by total serum lipid levels. 相似文献
998.
Patients' perceptions of their clinical interactions: development of the multidimensional desire for control scales 总被引:2,自引:0,他引:2
Anderson Lynda A.; DeVellis Robert F.; Boyles Barbara; Feussner John R. 《Health education research》1989,4(3):383-397
Interventions oriented toward enhancing patient-provider communicationwill benefit from having a satisfactory measure of patientsdesires for control in clinical interactions. Findings fromtwo studies are reported describing the development and validationof the Multidimensional Desire for Control (MDC) Scales. A totalof 160 patients with non-insulin-dependent diabetes (NIDDM)participated in the first study, which was designed to developand validate a measure of patients desires for control.Factor analysis yielded three subscales reflecting patientsdesires for: (i) personal, (ii) clinician, and (ii) shared controlin the interaction. Alphas for the three subscales were high( 0.750.86). Correlations with other measures of controlwere suggestive of good construct validity. The second investigationinvolves a replication study verifying the factorial compositionand validity of the scales. An independent sample of 109 patientswith NIDDM participated in this study. Findings support thereliability of the subscales (0.750.81). Furthermore,patients desires for control were significantly associatedwith patient satisfaction, with desire for personal controlnegatively related to patient satisfaction (r = 0.30,0.41, affective and behavioural dimensions, respectively)and desire for clinician control positively related to satisfaction(r = 0.44, 0.28, 0.31, affective, behavioral, and cognitivedimensions, respectively). 相似文献
999.
Biochemical characterisation of para-aminophenol-induced nephrotoxic lesions in the F344 rat 总被引:5,自引:0,他引:5
Kevin P. R. Gartland Frank W. Bonner John A. Timbrell Jeremy K. Nicholson 《Archives of toxicology》1989,63(2):97-106
The acute biochemical effects of the nephrotoxin p-aminophenol (PAP) were studied in detail using a combination of conventional bioanalytical and 1H-NMR spectroscopic methods. Dosing PAP (25–100 mg/kg) to male F344 rats resulted in a dose-related proximal nephropathy with consequent elevations in urinary enzymes, glucose, and urine total protein as shown by conventional methodology. 1H-NMR spectroscopy at 400 MHz of urine from PAP-treated rats also revealed a characteristic glycosuria, with concomitant amino aciduria. The increased excretion of these compounds indicates functional defects in the proximal tubule and reduced solute reabsorption efficiency. In addition, 1H-NMR urinalysis and conventional enzymatic analysis showed a dose-related lactic aciduria. Other changes detected by 1H-NMR included a dose-related reduction in the excretion of citrate (confirmed by a conventional biochemical method) and an increase in the excretion of acetate. The degree of abnormalities shown by 1H-NMR urinalysis agreed well with histopathological observations and conventional biochemical indices of nephrotoxicity. 1H-NMR urinalysis therefore serves to highlight changes in the excretion of low MW urine components not routinely studied by conventional biochemical analysis.Abbreviations ALP
alkaline phosphatase
- APAP
paracetamol
- BUN
blood urea nitrogen
- GFR
glomerular filtration rate
- GOT
glutamate oxaloacetate transaminase
- LAP
leucine aminopeptidase
- LDH
lactate dehydrogenase
- MW
molecular weight
- NAG
N-acetyl--D-glucosaminidase
- PAP
p-aminophenol
- ppm
parts per million
- TMAO
trimethylamine N-oxide
- UFR
urine flow rate 相似文献
1000.
Richard O. Shillaker Graham M. Bell John T. Hodgson Michael D. J. Padgham 《Archives of toxicology》1989,63(4):283-288
Current European Community (Annex V) guidelines recommend the use of 20 test animals in the guinea pig maximisation test for skin sensitisation. The suitability, for classification and labelling purposes, of reducing the number of test animals has been examined by analysing the results of 40 studies submitted to the Health and Safety Executive, and by the use of a mathematical model. Our results suggest that in most cases an experiment with ten test animals can be used to determine satisfactorily whether a substance should be labelled with the risk phrase may cause sensitisation by skin contact. However, serious consideration should be given to the need for additional investigation if two or three of the ten test animals show a sensitisation response. The highest nonirritant concentration of a substance should be used at challenge. Clearer guidance in Annex V on evaluating challenge responses would be beneficial. 相似文献