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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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Over a period of two years (1986-1987), the authors have studied the morbidity and mortality of various cardiovascular diseases in a hospital population of 268 patients. By comparing it with a previous similar study conducted over 5 years (1981-1985), they have reached the following conclusions: the prevalence of the main nosological groups is equivalent (H.B.P., rheumatoid valvulopathies, chronic pulmonary heart, ischemic cardiopathies; severity of the valvulopathies and their prognosis which raise social and medical problems especially that of cardiac surgery, still inexistent in Guinea; increased prevalence of diseases such as hypertension and rheumatoid valvulopathies. They suggest early screening, especially for rheumatoid valvulopathies and hypertension, which cause major social problems because of their complications. Besides, it would be desirable that visits at regular intervals be made mandatory in schools and universities and at preemployment examinations and in all SMI (?) centers in the country.  相似文献   
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To determine the predictive value of chloroquine (CQ) resistance markers in Senegal, Plasmodium falciparum DNA polymorphisms in pfmdr1and pfcrt were examined in relation to clinical outcome. Despite CQ treatment, 17% of patients had parasitemia after 28 days. Examination of molecular markers of CQ resistance revealed that 64% of all isolates had the T76 resistant allele at the pfcrt locus, while 30% carried the Y86 resistant allele at the pfmdr1 locus. The pfcrt T76 allele was present not only in all in vivo resistant isolates, 89% of in vitro resistant isolates, but also in 35% of in vitro sensitive isolates. The pfmdr1 N86Y polymorphism did not correlate with in vitro or in vivo CQ resistance. Our data suggest that the pfcrt T76 allele alone is required but not a sufficient predictor for in vivo CQ resistance.  相似文献   
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Our study justified by the frequency of acute appendicitis and the possibility of anatomic variations of the caecoappendicular area attempt to index the topographic variations of the vermiform appendix (v.a.). On 80 fresh native cadavers (62 men and 18 women) without surgical antecedent whose mean age was 36 years (range between 16 and 78 years) we note the morphotype and the height. More over we study the intraperitoneal projection of the Mac Burney point, topography and shape of the cecum and the situation, shape and dimensions of the v.a. We note also the level of implantation of this latter on the cecum, appearance of the mesoappendix and the distance separating the base of the appendix to the ileo-caecal junction. Mac Burney's point permitted to localize appendix in 66%; the cecum has more often than not the form of a bulb (98.7%) and sited in right fossa iliaca. We noted 7 types of topographic disposition; front varieties were more frequent (68.7%) notably the pelvic direction (51.2%) with a medial (72.5%) or a posteromedial (27.5%) establishment on the cecum. The v.a. was more often in the form of worm with a long mesoappendix; his mean length was 106.4 mm (between 65 and 160 mm) and the mean diameter 6.77 mm (range between 4 and 10 mm). The distance which separated the base of the appendix to the ileo-cecal junction varied between 15 to 40 mm with a mean distance of 24.2 mm. Thus in this study, dimensions of the v.a. were very variables. Located in right fossa iliaca he adopted a front topography with pelvic direction and medial establishment on bulbar cecum. In spite of scarcity of ectopic situation of the appendix for which laparoscopic approach is salutary, a similar topographic study during surgical treatment of acute appendicitis will be interesting.  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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Parasitological, malacological and anthropological studies were performed to assess the prevalence of Schistosoma haematobium and S. mansoni in schoolchildren living in the suburban area of Bamako. A total of 1017 schoolchildren aged 6-14 years were selected in two different areas between September 1997 and December 1999. In Djikoroni, the prevalence of S. haematobium and S. mansoni was 80.7% (339/420) and 22.8% (85/372) respectively. There was no significant difference of prevalence and intensity of infection with S. haematobium between schools, gender and age (p > 0.05), whereas, those of S. mansoni were higher in the vicinity of (+/- 100 m from) major sites where infected Biomphalaria pfeifferi were found (p < 0.001). In Niomirambougou, S. haematobium was prevalent in 46.7% (279/597) and S. mansoni in 28.2% (134/475). Boys and children aged 11-14 years were more infected (p < 0.001). Associated intestinal helminths (Hymenolepis nana, Necator americanus and Ascaris lumbricoides) were relatively scarce (prevalence < 1%). The prevalences of schistosome infected snails intermediate host were relatively high, 49.3% (100/203) in B. pfeifferi, 20.6% (88/138) in B. truncatus and 24.1% (7/29) in B. globosus. We recorded a total of 2514 water contacts about which 1130 in December and 1384 in January. Most of the children, 42.9% (1077/2511) were attracted to water bodies for bathing, swimming and playing, suggesting the lack of recreational facilities in these areas. Developing local control programmes in schools located in the vicinity of water bodies would contribute to break the parasite transmission cycle in Bamako.  相似文献   
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