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The retention of autopolymerized and light-polymerized Delton fissure sealants was compared. Sealants were applied to 207 first permanent molars with 304 separate sites in 73 children 6-8 years old (mean age 6.3 years). After five years, there was complete retention in 59% of the autopolymerized and 48% of the light-polymerized sealants. The resulting 11% difference in retention rates was not statistically significant at P less than 0.05.  相似文献   
103.
This is the first report of neurovesical dysfunction in a woman with postural tachycardia syndrome (POTS). The patient had both symptoms and urodynamic findings diagnostic of detrusor hyperreflexia. Management consisted of anticholinergic medication and timed voiding. Lower urinary tract dysfunction may be underrecognized in POTS.  相似文献   
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A model utilizing human umbilical cord blood was used to screen for hypoglycemia in a simulated neonatal situation. The aims of the study were to assess the effect of increasing Hct concentration on Dextrostix readings, and to determine whether plasma samples, in contrast to conventional whole blood samples, were acceptable for Dextrostix determinations in selected cases. Dextrostix readings were determined on 65 whole blood samples of varying Hct, and on plasma specimens, 48 of which were paired with whole blood samples. The results were compared with plasma true glucose values. Plasma Dextrostix readings correlated well with true glucose values throughout the entire Hct range (r = .94, slope = 1.16). Whole blood Dextrostix readings, on the other hand, were Hct-dependent and, with increasing Hct values, became falsely low. As a result, a Hct values greater than 70%, whole blood Dextrostix readings were less than 50% of the true glucose value (r = .94, slope = 0.45). Plasma Dextrostix determinations may offer an accurate means of screening for neonatal hypoglycemia in asymptomatic infants with high Hct, pending laboratory glucose results.  相似文献   
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Background

In this study the concentration of lysozyme in blood plasma of Microtus agrestis, Clethrinomys glareolus, Apodemus sylvaticus, BK rats and outbred white mice before and after infection with culture forms of Trypanosoma microti, T, evotomys, T. grosi, T. lewisi and T. musculi respectively was measured.

Methods

Blood samples of rodents, Microtus agrestis, Clethrionomys glareolus, Apodemus sylvaticus, BK rats and outbred mice infected with T. microti, T. evotomys, T. grosi, T. lewisi and T. musculi respectively were collected in heparinized micro- tubes immediately before inoculation and 3, 6, 12, 24, 48, 96 and more than 400 days after intra- perituneal inoculation with 5×105of their homologous trypanosome parasites of which more than half were metacyclic trypomastigote in 0.2 ml of culture medium. Micro- tubes were centrifuged and plasma samples were separated and the lysozyme activity was measured by the agar method.

Results

Levels of lysozyme rose rapidly three to six days after the inoculation to ten to twenty than their pre- infection levels. They then gradually decreased, although after more than one year they were still two to ten folds higher than controls. The highest level measured occurred in rats infected with T. lewisi and the lowest in A. sylvaticus infected with T. grosi. After one year the highest concentration of lysozyme was in mice infected with T. musculi and lowest in A. sylvaticus.

Conclusion

Persistent enhanced lysozyme levels may prevent re- infection with trypanosomes.  相似文献   
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