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811.
812.
This study investigated the association between caries status and sealant need at a prior survey and subsequent sealant use in a Medicaid program. Clinical data from a 1986-87 statewide epidemiological survey (N = 8026) representative of North Carolina (NC) schoolchildren (grades K-12) were linked with all NC Medicaid dental claims submitted during 1987-92, yielding 570 children in the survey who had at least one dental visit during 1987-1992. From the 570, 390 children were included: 71 who received sealants (S) and 319 who received non-sealant care (NS). Children were excluded based on age, having preexisting sealants, or having no sealant-eligible molars or premolars. S and NS were compared on baseline dfs, DMFS, and sealant need, controlling for the patient's age, number of visits, and the provider's propensity to seal. At all ages, NS was twice as likely to have had prior dfs or DMFS (OR = 2.04, 95% CI = 1.15, 3.70). The association between sealant receipt and prior sealant need varied by age. At 6 to 11 years, S and NS had equal likelihood of sealant need (OR = 1.41, 95% CI = 0.62, 3.18). At 12 to 15 years, NS had a greater likelihood of sealant need (OR = 6.82, 95% CI = 1.60, 29.08). Caries-free status was associated with subsequent sealant receipt. Prior sealant need caused variability in dentists' decisions, depending on the child's age and past caries experience. Sealants were used infrequently by most providers and for a minority of patients. These findings are important for the Medicaid program and for future non-randomized studies of sealant effectiveness. 相似文献
813.
We have examined the ryanodine receptor, Ca(2+)-ATPase, calsequestrin and phospholamban mRNA levels in the left ventricles of pacing-induced heart failure and norepinephrine infusion dogs. The heart failure dogs showed a decrease in the levels of ryanodine receptor and Ca(2+)-ATPase mRNAs. Norepinephrine infusion caused a reduction of Ca(2+)-ATPase mRNA but no change in ryanodine receptor mRNA. There was a corresponding reduction of the immunoreactive Ca(2+)-ATPase protein levels in both heart failure and norepinephrine infusion animals compared to controls. In contrast, the mRNAs of calsequestrin and phospholamban were unchanged in dogs with either congestive heart failure or norepinephrine infusion. Thus, since norepinephrine infusion and congestive heart failure produced similar reductions of Ca(2+)-ATPase mRNA and protein, we postulate that the down-regulation of Ca(2+)-ATPase in congestive heart failure may be caused, at least in part, by sympathetic stimulation that occurs in heart failure. 相似文献
814.
RM Mader AE Sieder J Braun B Rizovski M Kalipciyan MW Mueller R Jakesz H Rainer GG Steger 《Canadian Metallurgical Quarterly》1997,54(11):1233-1242
Cellular resistance to 5-fluorouracil (5-FU) is not completely understood. Since 5-FU shares the pyrimidine pathway with the physiological pyrimidines, we investigated the relationship between fluoropyrimidine metabolism, nucleic acid uptake and cytotoxicity of 5-FU in eight colon tumour cell lines including 5-FU-resistant subclones. The cytotoxicity of 5-FU was increased up to 423-fold when the anabolites 5-fluorouridine (FUrd), 5-fluorodeoxyuridine (FdUrd), and 5-fluorodeoxyuridine monophosphate (FdUMP) were compared with the parent drug in vitro. The enzymes uridine phosphorylase and thymidine phosphorylase were predictive for the cytotoxicity of 5-FU in 5/7 cell lines. Inhibition of uridine phosphorylase and thymidine phosphorylase by antisense strategies effectively antagonised 5-FU, abolishing 84% and 79% of its toxicity. The importance of thymidine phosphorylase was supported by a highly restricted enzyme activity in 5-FU-resistant cells. In 5-FU naive cells, a stimulating effect of 5-FU on thymidylate synthase mRNA and ribonucleotide reductase mRNA expression was observed. In these cells, antisense oligonucleotides to ribonucleotide reductase significantly reduced cell growth. Downregulation of ribonucleotide reductase mRNA in 5-FU-resistant subclones suggests different mechanisms in primary and secondary resistance to 5-FU. Most of the intracellular 5-FU was selectively incorporated into RNA (range: 45-91%) and generally spared DNA (range: 0.2-11%). In synthesising our data, we conclude that drug resistance could be overwhelmed through bypassing limiting steps in the activation of 5-FU. In the majority of colonic tumours, the activity of uridine phosphorylase and thymidine phosphorylase may have prognostic relevance for the cytotoxicity of 5-FU in vitro. 相似文献
815.
Based on analysis of aligned amino acid sequences the following statements are made: (i) There is evolutionary homology between the N-terminal extracellular region of ionotropic Glutamate receptors/Kainate Binding Proteins and a family of procaryote amino acid binding proteins. (ii) Homology of the N-terminal extracellular domain of the metabotropic glutamate receptors with a family of receptors with a guanylate cyclase intracellular domain appears to be valid. (iii) There is no evidence for homology between the N-terminal extracellular domain of the nicotinic Acetylcholine, GABA, Glycine and 5HT3 receptors and that of the ionotropic Glutamate receptors/Kainate Binding proteins. (iv) The proposal of homology for the N-terminal extracellular domain of metabotropic Glutamate receptors and that of ionotropic Glutamate receptors does not appear to hold. 相似文献
816.
817.
CA Conover LC Hartmann S Bradley P Stalboerger GG Klee KR Kalli RB Jenkins 《Canadian Metallurgical Quarterly》1998,238(2):439-449
Current hypotheses for explaining which sex cares for offspring assume a relationship between the mode of fertilization and the sex showing parental care. In general, it is hypothesized that maternal care should be concentrated in taxa with internal fertilization, and paternal care should be concentrated in taxa with external fertilization. Studies have supported this relationship; however, new comparative techniques and new data on parental care and the frequency of internal fertilization in anurans suggest that the relationship should be re-evaluated. I examined the relationship between mode of fertilization and sex providing parental care in 334 taxa of anurans using concentrated changes tests and in 396 taxa of anurans using a method developed by Ridley (1983. The Explanation of Organic Diversity. The Comparative Method and Adaptations of Mating. Oxford: Clarendon). The results of the concentrated changes tests showed that both female and male parental care are randomly distributed among taxa with respect to mode of fertilization. However, using Ridley's method, I found significant relationships between mode of fertilization and sex providing parental care. The observed and expected numbers of transitions from external fertilization and no parental care to external fertilization and male parental care or to internal fertilization and female parental care are not qualitatively different. Therefore, the results of my analyses suggest that current hypotheses for explaining the occurrence of maternal versus paternal care in anurans should be reconsidered. Copyright 1998 The Association for the Study of Animal Behaviour. 相似文献
818.
We previously demonstrated a prognostic significance of maternal oxygen test in predicting imminent fetal distress. The purpose of this study was to investigate eventual other factors related to the length of the time interval elapsing between the Doppler diagnosis of brain sparing effect and abnormal fetal heart rate patterns. To this end we considered 101 growth-retarded fetuses free of structural and chromosomal abnormalities with a ratio between the pulsatility indices of umbilical and middle cerebral artery above the 95th centile in presence of a normal fetal heart rate pattern. The factors, other than the oxygen test, analyzed for a potential influence on this time interval were gestational age, presence of hypertension or preeclampsia, amniotic fluid index, severity of growth retardation (centile of the ultrasonographic estimated fetal weight) and 9 different Doppler indices calculated from extra- and intracardiac districts. Statistical actuarial methods were used to determine the effect of these prognostic factors on the duration of this time interval. The occurrence of abnormal fetal heart rate patterns (antepartum late heart rate decelerations) was used as censoring variable. The time interval between the entry in the study and delivery ranged from 1 to 39 days. Indications for delivery were fetal distress in 53 fetuses (52.4%) and different maternal or fetal complications in the remaining 48 fetuses.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
819.
820.
GG Roshchin VV Burluka NI Tutchenko VN Denisenko IP Shlapak NN Baramiia 《Canadian Metallurgical Quarterly》1997,(7-8):40-42
Clinico-statistical analysis of the treatment results of 624 injured persons for the period from 1990 till 1995 year was conducted. In 509 (81.6%) of them the combined closed thoracic trauma was revealed, in 15 (18.4%)--the isolated closed affection of the skull, thorax, abdomen and extremities have occurred. The anatomic-functional model of the injury severity and prognosis outcome estimation was elaborated, an optimal timing and surgical treatment methods of the thoracic cage bones injury was substantiated, what have promoted to lower lethality from 50%--in injured persons, operated on without taking into account the trauma severity and prognosis outcome, to 31.6%--in operated on in the postponed order. 相似文献