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21.
BA DARLOW TE INDER KB SLUIS G NUTHALL N MOGRIDGE CC WINTERBOURN 《Journal of paediatrics and child health》1995,31(4):339-344
Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
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4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is an important
metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-
(3-pyridyl)-1-butanone (NNK). Using the chiral derivatizing agent, (R)-
(+)-alpha-methylbenzyl isocyanate [(R)-(+)-MBIC], previous work has shown
that the enantiomeric ratio of metabolically formed NNAL and its
glucuronide derivative may be species dependent. However, the absolute
configuration of such NNAL has not been previously reported. Synthetically
prepared racemic NNAL was converted to diastereomeric esters by reaction
with (R)-(+)- and (S)-(-)-alpha-methoxy-alpha-
(trifluoromethyl)phenylacetic acid (MTPA) chloride (Mosher's reagent) and
the products were characterized by 1H-NMR. Based on chemical shift data,
the absolute configuration of NNAL in each diastereomeric ester was
assigned. Hydrolysis of (R)-NNAL-(R)-MTPA gave (R)-NNAL. This was converted
to the corresponding carbamate by reaction with (R)-(+)-alpha- MBIC and the
absolute configurations of the diastereomeric carbamates formed by reaction
of (R)- and (S)-NNAL with (R)-(+)-MBIC were thereby assigned. Conversion of
metabolically produced NNAL to the same carbamates allowed us to assign the
NNAL formed from NNK by rat liver microsomes as (R)-NNAL. The major and
minor NNAL-glucuronide diastereomers found in the urine of patas monkeys
and humans exposed to NNK were similarly assigned; they were formed from
(R)-NNAL and (S)- NNAL, respectively.
相似文献
24.
Fifty seven children with thoracic empyema (37 boys and 20 girls) aged less than 12 years were seen at the University of Port Harcourt Teaching Hospital between January 1989 and December 1991. Staphylococcus aureus was the most common organism isolated from the pus of these patients (36 (63%) patients). Pseudomonas aeruginosa, the next most common organism, was isolated in 10 (18%) patients. The most common symptoms at presentation were acute illness with fever and cough (51 (89%) patients). All the patients were treated with closed intercostal tube drainage and appropriate antibiotics. Decortication was resorted to in only one patient. There were two deaths and the overall survival rate was 97%. 相似文献
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26.
Summary The involvement of the peripheral motor and sensory nerve, at least on a subclinical level, is a nearly constant event with chronic renal failure. The study of the motor and sensory propagation velocity indicates that a widespread functional lesion of the axon with a peripheral point of attack and secondary demyelination, may be the basic pathogenetic event of uremic polyneuropathy. Prolonged hemodialytic treatment is substantially unable to influence the evolution of uremic polyneuropathy. The electrophysiological follow-up study of the peripheral nerve does not seem to be an index of adequate dialysis.
Zusammenfassung Die Beteiligung des peripheren motorischen und sensiblen Nerven, zumindest subklinisch, ist bei chronischer Niereninsuffizienz Regel. Die Untersuchung der motorischen und sensorischen Erregungsleitungsgeschwindigkeit spricht dafür, daß bei der urämischen Polyneuropathie als wesentliches pathologisches Geschehen das Axon besonders distal ausgedehnt betroffen ist mit einer sekundären Demyelinisation. Auch langdauernde Hämodialyse scheint nicht in der Lage zu sein, die Entwicklung der urämischen Polyneuropathie zu beeinflussen. Die elektrophysiologische fortlaufende Kontrolle des peripheren Nerven scheint nicht ein brauchbarer Parameter für eine wirksame Dialyse zu sein.相似文献
27.
To determine whether the prolonged bleeding time so common to chronic renal failure (CRF) was due to defective factor VIII-related activities, as in von Willebrand's disease, vascular-factor VIII-related protein was measured in patients with CRF. Factor VIII-related protein was detected by immunofluorescence on the vascular intima of all 13 patients with CRF and greatly prolonged bleeding times. This protein was also present on the vascular intima of a patient with CRF and moderate von Willebrand's disease. These findings support a previous suggestion that the disturbed haemostasis in patients with CRF is not linked to defective factor VIII-related activities. 相似文献
28.
29.
30.
Complication of cochlear implantation surgery 总被引:1,自引:0,他引:1
Mecca MA Wagle W Lupinetti A Parnes S 《AJNR. American journal of neuroradiology》2003,24(10):2089-2091
After experiencing gradual, progressive sensorineural hearing loss, a patient underwent cochlear implant (CI) surgery. Postoperatively, the patient experienced vestibular symptoms with no improvement in hearing. High-resolution temporal bone CT scanning demonstrated extracochlear positioning of the CI electrode in the superior semicircular canal. 相似文献