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ABSTRACT. The phonological abilities of two groups of 4–9-year-old intellectually impaired Cantonese-speaking children are described. Children with Down's syndrome did not differ from matched non-Down's syndrome controls in terms of a lexical comprehension measure, the size of their phoneme repertoires, the range of sounds affected by articulatory imprecision, or the number of consonants, vowels or tones produced in error. However, the types of errors made by the Down's syndrome children were different from those made by the control subjects. Cantonese-speaking children with Downs syndrome, as compared with controls, made a greater number of inconsistent errors, were more likely to produce non-developmental errors and were better in imitation than in spontaneous production. Despite extensive differences between the phonological structures of Cantonese and English, children with Downs syndrome acquiring these languages show the same characteristic pattern of speech errors. One unexpected finding was that the control group of non-Down's syndrome children failed to present with delayed phonological development typically reported for their English-speaking counterparts. The argument made is that cross-linguistic studies of intellectually impaired children's language acquisition provide evidence concerning language-specific characteristics of impairment, as opposed to those characteristics that, remaining constant across languages, are an integral part of the disorder. The results reported here support the hypothesis that the speech disorder typically associated with Down's syndrome arises from impaired phonological planning, i.e. a cognitive linguistic deficit.  相似文献   
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Administration of a soluble protein into animals prior to challenge immunization induces immunological tolerance which is specific for the protein. In addition, chemical modification of proteins with polyethylene glycol (PEG) has been reported to convert the immunogenic proteins to become tolerogenic. However, differences in tolerogenic properties between PEG-modified proteins and the native counterparts have never been analysed. The ability of PEG-conjugated type II collagen (PEG-CII) to attenuate CIA, an animal model for rheumatoid arthritis, was compared with the native unconjugated CII. Groups of DBA/1 J mice were treated weekly with i.p. injections with PEG-CII, native CII, or vehicle alone for 3 weeks, before they were challenged with CII in adjuvants. The induction of tolerance was confirmed in both PEG-CII- and CII-pretreated mice when suppression of lymph node T cell proliferation in response to CII was noted. The degrees of suppression of T cell proliferation were comparable between the two pretreated groups. However, induction of arthritis and production of IgG anti-CII antibody were more markedly suppressed in PEG-CII-pretreated mice than in native CII-pretreated mice, although the severity of arthritis and antibody levels in the latter group were also lower than in control mice. IgG2a and IgG2b antibody levels were equally suppressed in the two pretreated groups, whereas the IgG1 level was significantly lower in the PEG-CII-pretreated group than in the native CII-pretreated group. The results provide the first evidence that attachment of PEG to CII renders the protein more tolerogenic.  相似文献   
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Objectives: A prospective study comparing the efficiacy and side-effects of oral sulindac with intravenous indomethacin in clinically stable preterm infants (<1750 g) requiring non-invasive closure of haemodynamically significant patent ductus arteriosus.
Methodology: As maturity and birthweight are the two major determinants of ductal closure, infants were matched as closely as possible for these parameters. An eligible patient was first assigned to the sulindac group and a subsequent patient with similar gestational age (± 1 week) and birthweight (±100 g) to the previously recruited infant would automatically receive indomethacin. A total of eight infants were enrolled in each group.
Results: The ductus arteriosus was successfully closed in all eight infants receiving indomethacin, and in seven of eight infants receiving sulindac. No significant differences were found with regards to the ductal size between the two groups at diagnosis or on each of the consecutive days of treatment ( P >0.25). More renal adverse effects were encountered in the indomethacin group. Significant differences in changes from baseline value for urine output, plasma sodium, urea and creatinine concentrations were noted at 24, 48 and 72 h after commencement of treatment between the two groups ( P <0.05). All the parameters returned to normal or pre-treatment levels 48 h after stopping therapy. Unexpectedly, severe gastrointestinal complications were encountered in the sulindac group.
Conclusions: Sulindac is capable of promoting ductal constriction in clinically stable preterm infants without compromising the renal function. The spectrum of gastrointestinal complications observed in sulindac treated infants were similar to those described for indomethacin. The use of sulindac for ductal closure in the preterm infant should remain experimental.  相似文献   
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Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis.  相似文献   
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OBJECTIVE—To evaluate the role of vitamin A on renal scarring in recurrent urinary tract infections (UTIs).
DESIGN—Twenty three children with UTIs and renal scarring (mean (SD) age 7.3 (3.9) years) and 91 children without renal scarring (6.4 (3.4) years) were studied. All the children had serum vitamin A and β-carotene measurements and nutritional evaluation. Renal scarring was assessed by technetium-99m dimercaptosuccinic acid (99mTc DMSA) scanning. Nutritional status of all the patients was within normal limits and not different between the groups.
RESULTS—Mean (SD) serum vitamin A and β-carotene concentrations were not significantly different between the patients with and without renal scarring (vitamin A 53.2 (22.6)/46.8 (17.0) µg/dl and β-carotene 232.3 (201.3)/272.4 (86.0) µg/dl respectively). However, when the patients with renal scarring and with greater than 10% difference among the DMSA uptakes of their kidneys (11 cases) were evaluated, a significant negative correlation was determined between the serum vitamin A concentrations and the magnitude of the difference in uptakes of each kidney. The same relation was not true for serum β-carotene concentrations.
CONCLUSION—This study demonstrated a relation between serum vitamin A concentrations and magnitude of hypoactivity in 99mTc DMSA scanning in kidneys with advanced scarring.

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BACKGROUND: The aim of this study was to compare the effectiveness of an intensive asthma education program (group B) with that of a standard asthma education program (group A). METHODS: A prospective randomized single blinded study was conducted in the pediatric department of a public hospital in Hong Kong. Children aged 2-15 years admitted to the pediatric department with an acute attack of asthma were recruited. A standard asthma education program (group A) or an intensive asthma education program (group B) for children were offered. The main outcome measures include the number of visits to the emergency department and the number of hospitalization for asthma during the 3 month follow-up period. RESULTS: A total of 45 children were in group A and 55 in group B. Group B had statistically significant reductions in the number of visits to the emergency department and the number of hospitalizations. Drug compliance was also significantly improved in group B. Parents' satisfaction rate was also higher in group B. CONCLUSION: The intensive asthma education program might be more cost effective than the standard asthma education program in the management of asthmatic children admitted to hospital in Hong Kong.  相似文献   
10.
To determine whether the possible oxidative effect of methotrexate (Mtx) on ovary and to evaluate the effectiveness of alpha lipoic acid (ALA), which may be useful in many oxidative stress models.

Thirty-two female Wistar-albino rats were randomly divided into four groups; control group, alpha lipoic acid group (ALA 100?mg/kg, 10?days), multiple dose Mtx group (Mtx 1?mg/kg 1, 3, 5, 7?days) and Mtx and ALA group (Mtx 1?mg/kg 1, 3, 5, 7?days and ALA 100?mg/kg, 10?days). Serum total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI), tumor necrosis factor-alpha (TNF-α), tissue malondialdehyde (MDA) and activities of glutathione peroxidase (GSH-Px) and catalase (CAT) and anti-Mullerian hormone (AMH) and total ovarian follicle count were evaluated.

Mtx administration caused a significant decrease in TAS, a significant increase in TOS and OSI, a significant increase in MDA levels and a decrease in GSH-Px and CAT activity. Moreover the proinflammatory cytokine (TNF-α) was increased in the Mtx group. And AMH values and total follicle count were significantly decreased in Mtx group. However, ALA treatment reversed biochemical results and AMH levels and total follicle count.

Alpha lipoic acid ameliorates methotrexate induced oxidative damage of ovarian in rats.  相似文献   
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