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991.
992.
Upper airway measurements in nine infants considered to be at risk of upper airway insufficiency, six of whom presented after an apnoeic episode, were compared with measurements taken in two age groups of healthy infants. Paired, inspiratory and expiratory, lateral upper airway radiographs were obtained while the infants were awake and breathing quietly. The radiographs of all nine infants demonstrated narrowing in the oropharyngeal portion of the airway during inspiration and in six infants there was ballooning of the upper airway during expiration. Seven of the nine infants subsequently experienced recurrent apnoeic episodes which required vigorous stimulation to restore breathing. Experience suggests that respiratory phase timed radiographs are a useful adjunct to the evaluation of infants who are suspected of having upper airway dysfunction. They provide information regarding both the dimensions and compliance of the upper airway as well as the site of any restriction.  相似文献   
993.
One hundred and ninety three children with asthma and 318 controls aged 1-4 years were evaluated for atopic heredity and exposure to possible indoor risk factors for asthma-for example exposure to furred pets, tobacco smoke, and home dampness. A subgroup of cases were classified as cat and/or dog allergic on the basis of skin prick tests. Heredity for asthma was a significant risk factor (odds ratio (OR) 3.0, confidence interval (CI) 2.1 to 4.6). Environmental tobacco smoke was associated with an excess risk for asthma (OR 1.7, CI 1.1 to 2.3) and signs of home dampness tended to increase this risk (OR 1.3, CI 0.9 to 2.0). High dose exposure to cat and/or dog resulted in an increased risk only in asthma cases sensitised to cat and/or dog (OR 2.7, CI 1.0 to 7.3). A combination of high dose exposure to cat and/or dog, environmental tobacco smoke and damp housing was associated with an OR of 8.0 (CI 1.9 to 34.1). Raised indoor humidity has been shown to reflect low air exchange, which may also lead to increased doses of inhaled aeroallergens and tobacco smoke, and contribute to the interaction between the three risk factors.  相似文献   
994.
995.
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
996.
997.
Seven-week-old Apc1638N mice were exposed to a single dose of 5 Gy total-body X-irradiation resulting in a 8-fold increase in the number of intestinal tumors and a reduction of the lifespan to an average of 6 months. The distribution of tumors along the intestinal tract as well as the adenoma/carcinoma ratio, were similar between non-irradiated and irradiated animals. Semi-quantitative PCR analysis of intestinal-tumor DNA revealed that 10 out of 14 tumors had lost the wild-type Apc allele. However, in contrast to spontaneous Apc1638N intestinal tumors in which the LOH event at the Apc locus involves the entire chromosome 18 (1), in 6 out of 10 tumors derived from X-irradiated animals the Apc loss is associated with only a partial intrachromosomal deletion. The remaining tumors have lost all chromosome 18 markers tested. In addition to the intestinal tumors, female Apc1638N mice are susceptible to the development of mammary tumors. Upon X-irradiation, Apc1638N mice show a striking 15-fold increase in mammary tumors. Moreover, Apc1638N mice spontaneously develop other extra-intestinal neoplasia, such as desmoid-like lesions similar to those associated with familial adenomatous polyposis (FAP), the human syndrome caused by germline mutations in the APC gene. Spontaneous desmoid growth is sex-dependent, as male Apc1638N mice develop 3-fold more desmoids than female mice. Interestingly, X-irradiation seemed to increase the number of desmoids per animal nearly twofold only in female Apc1638N mice. Five out of 9 desmoids found in Apc1638N mice exposed to X-ray displayed loss of the wild-type Apc allele.   相似文献   
998.
Early diet of preterm infants and bone mineralization at age five years   总被引:1,自引:0,他引:1  
Bone disease with significantly reduced bone mineralization is common in preterm infants, and associated with later linear growth stunting at 18 months of age. Dietary insufficiency of calcium and phosphorus is thought to be the principal aetiological factor. We studied 54 children at mean age 5 years who were born preterm and had participated in a prospective multicentre study of effects of early diet on later growth and development. Diets compared were banked donor breast milk and preterm formula fed as a supplement to mother's own milk. Increasing human milk intake was strongly positively associated with later bone mineral content. Children fed predominantly human milk had greater bone mineral content than children of similar size born at term. These data suggest that the early nutritional environment of the preterm infant could play an important role in determining later skeletal growth and mineralization.  相似文献   
999.
OBJECTIVE: To describe the clinical and microbiological characteristics of infants and children with bone and joint infections caused by penicillin-susceptible and penicillin-nonsusceptible strains of Streptococcus pneumoniae. DESIGN: Multicenter, prospective patient accrual; retrospective chart review of identified patients. SETTING: Eight children's hospitals in the United States. PARTICIPANTS: Forty-two children with bone and/or joint infections prospectively enrolled in the United States Pediatric Multicenter Pneumococcal Surveillance Study from September 1, 1993 to August 31, 1996. OUTCOME MEASURES: Data were collected on multiple variables, including age, gender, race, days of symptoms before and during hospitalization, antibiotic and surgical therapy, laboratory and imaging studies. RESULTS: Of the 42 children enrolled (21 bone, 21 joint infections), 14 had isolates that were not susceptible to penicillin. Eight of 16 (50%) strains isolated from children who received antibiotics within 4 weeks before hospitalization were not susceptible to penicillin, compared with 4 of 15 (27%) strains isolated from children without previous antibiotic exposure. Clinical response to therapy was similar between children infected by penicillin-susceptible strains compared with those infected by penicillin-nonsusceptible strains, including duration of hospitalization (9.1 days vs 11.2 days), days of intravenous antibiotic therapy (25.3 days vs 24.6 days), days of fever (3.6 days vs 3.1 days), and sequelae (14% vs 7%). The most commonly prescribed single agents for parenteral therapy in definitive treatment were ceftriaxone (36%), penicillin (15%), and clindamycin (15%). Oral therapy followed parenteral therapy in 56% of children. The mean (+/- standard deviation) duration of total antibiotic therapy in children with osteomyelitis was 57.5 +/- 48.6 days (range, 23-196 days) and 29.2 +/- 11.8 days (range, 12-67 days) for arthritis. Late sequelae (long-term destructive changes of the bone or joint) were documented in 5 (12%) children, 4 with osteomyelitis, and 1 with arthritis. Sequelae occurred in 30% of children with long bone osteomyelitis associated with infection in the adjacent joint. The age of children with sequelae was younger than those without sequelae (6.4 months vs 18.6 months). CONCLUSIONS: The demographic characteristics and anatomic sites of infection in our patients were similar to previously published series collected from single institutions before the emergence of significant antibiotic resistance in S pneumoniae. Our analysis suggests that children infected by penicillin-nonsusceptible strains have a similar clinical response to therapy when compared with children infected by penicillin-susceptible strains.  相似文献   
1000.
In allergy and asthma, the fine balance between the T helper (Th) 1, Th2 and T regulatory cytokine responses appears to be shifted towards Th2. Here, we report that synthetic lipopeptides which contain the typical lipid part of the lipoprotein of gram-negative bacteria stimulate a distinct regulatory cytokine pattern and inhibit several Th2 cell-related phenomena. The most potent analogue of synthetic lipopeptides, lipopeptide CGP 40774 (LP40) was not active in MyD88-deficient mice and stimulated Toll-like receptor (TLR)-2, but not TLR-4. LP40 potentiated the production of IFN-gamma and IL-10, but not IL-4 and IL-5 by human T cells. In addition, triggering of TLR-2 by lipopeptides promoted the in vitro differentiation of naive T cells towards IL-10- and IFN-gamma-producing T cells and suppressed IL-4 production by Th2 cells. Accordingly, LP40 inhibited IgE production induced by allergen, anti-IgD antibody, Nippostrongylus brasiliensis or murine acquired immunodeficiency virus. Furthermore, ovalbumin-induced lung eosinophilic inflammation was abolished and Schistosoma mansoni egg-induced granuloma size and eosinophil counts were suppressed in mice by LP40. These results demonstrate that stimulation of TLR-2 by lipopeptides represents a novel way for possible treatment of allergy and asthma by regulating the disrupted cytokine balance.  相似文献   
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