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991.
Findings coming from autopsies and serum of SARS patients suggest an important immune-inflammatory implication in the evolution to respiratory distress. Conditions such as HIV infection or treatment with immunosuppressors (in cancer or autoimmune diseases) are not among the bad prognosis factors for development of distress. To date, there have been no reported case fatalities in children, probably due to their more immature immune system. Our conclusions follow: (1) The milder form of SARS in children and the apparent protective factor that immunosupression represent rules out a significant viral cytopathic effect (they would be the most affected). (2) The evidence for immune implication in distress strongly supports immunomodulators for therapy: phosphodiesterase inhibitors (due to their down-modulating activity on proinflammatory cytokines); inhaled corticoids (aimed at producing a local immunomodulation); teophylline or nedocromil sodium (which prevents inflammatory cell recruitment into the airway wall). (3) An early immunomodulatory therapy, based on the levels of proinflammatory cytokines and clinical parameters to evaluate the respiratory function such as arterial oxygen saturation, could prevent the occurrence of distress. (4) Vaccine design should consider the immune origin of distress. (5) Physicians should be aware of mildly symptomatic patients (children, immuno-compromised hosts) to avoid transmission to immunocompetent adults.  相似文献   
992.
The knowledge of the roles and origins of different gonadotrophin-releasing hormone (GnRH) systems could greatly contribute to improve the understanding of mechanisms involved in the physiological control of early development, puberty and spawning. Thus, in this study, we have analyzed the distribution of the cells expressing salmon GnRH, seabream GnRH and chicken GnRH-II forms in the brain and pituitary of developing sea bass using specific antibodies to their corresponding GnRH-associated peptides. The first prepro-chicken GnRH-II-immunoreactive cells arose in the germinal zone of the third ventricle at 4 days after hatching, increasing their number from days 10 to 30, in which they adopted their adult position. The prepro-chicken GnRH-II-immunoreactive fibers became conspicuous in the first week and from day 26 they reached almost all brain areas, especially the hindbrain, being never detected in the pituitary. First prepro-salmon GnRH-immunoreactive cells were detected in the olfactory placode at day 7 after hatching and reached the olfactory bulbs at day 10. Migrating prepro-salmon GnRH cells arrived at the ventral telencephalon at day 15, and became apparent in the preoptic area from day 45. The prepro-salmon GnRH innervation was more evident in the forebrain and increased notably between 10 and 30 days, at which fibers already extended from the olfactory bulbs to the medulla. A few prepro-salmon GnRH-immunoreactive fibers were observed in the pituitary from day 30. The prepro-seabream GnRH-immunoreactive cells were first detected at day 26 in the rostral olfactory bulbs. On day 30, prepro-seabream GnRH-immunoreactive cells were also present in the ventral telencephalon, reaching the preoptic area and the hypothalamus at 45 and 60 days, respectively. The prepro-seabream GnRH innervation appeared restricted to the ventral forebrain, increasing notably during the sixth week, when fibers also reached the pituitary. A significant prepro-seabream GnRH innervation was not detected in the pituitary until day 60.  相似文献   
993.
994.
We describe a newborn boy with a gastric heterotopia located in the nasopharynx, which caused airway obstruction soon after delivery. Gastric heterotopia is an uncommon lesion generally found throughout the alimentary tract, but nasopharynx is an exceptional location. To our knowledge, this is the second reported case of gastric heterotopia located in the nasopharynx, and the first one presenting in a newborn with symptoms at birth and with an associated central nervous system mass.  相似文献   
995.
Trisomy 9p is a chromosome abnormality caused by duplication of the short arm of chromosome 9. Clinically it is characterized by psychomotor retardation, malformations that can affect various organs and sometimes epilepsy. Trisomy 9p may be the fourth most common autosomal trisomy, after trisomies 21, 13 and 18. Two new cases of trisomy 9p are described. Previous cases reported in Spain, associated clinical features, and the diagnostic and therapeutic approach to these patients are revised.  相似文献   
996.
997.
998.
Parental smoking behavior at home and sociodemographic variables may influence exposure to environmental tobacco smoke (ETS) in children. A sample of 115 preschool children aged 3-6 years was enrolled in this study. ETS exposure was evaluated through a questionnaire about parents' smoking behavior and determinations of urinary cotinine -- a biomarker of exposure -- in children. Bivariate and multiple regression analyses were used to evaluate the association between the smoking behavior of each parent at home, sociodemographic factors and cotinine levels in children. The parental perception of smokiness in the home was significantly associated with urinary cotinine in children (r-partial coefficient=0.324; P<0.002). The father's education, mother's smoking status, and day of the week when urine was sampled (Tuesday) were also independently associated with levels of cotinine. These four variables explained 26.4% of the variance in the cotinine levels of children. In designing educational programs to reduce passive smoking among children, it is necessary to take into account those factors related with cotinine levels in children. Our results support the influence of the mothers' smoking status, the fathers' educational level, and the day of the week of sampling on cotinine in children. The perception of parents (smokers and nonsmokers) about the smokiness in the home could also be a useful indicator of the cotinine in children exposed to environmental tobacco smoke in the household.  相似文献   
999.
An outbreak of hantavirus pulmonary syndrome occurred in the province of Los Santos, Panama, in late 1999 and early 2000. Eleven cases were identified; 9 were confirmed by serology. Three cases were fatal; however, no confirmed case-patient died. Case-neighborhood serologic surveys resulted in an overall hantavirus antibody prevalence of 13% among household and neighborhood members from the outbreak foci. Epidemiologic investigations did not suggest person-to-person transmission of hantavirus infection. By use of Sin Nombre virus antigen, hantavirus antibodies were detected in Oligoryzomys fulvescens and Zygodontomys brevicauda cherriei. This outbreak resulted in the first documented cases of human hantavirus infections in Central America.  相似文献   
1000.
BACKGROUND: The objective of this study was to establish the relationship between presence of anti-Chlamydia trachomatis and anti-HSP60 antibodies in serum and follicular fluid of infertile women. METHODS: Serum IgG and follicular fluid IgA to Chlamydia trachomatis and human heat shock protein 60 (HSP60) were determined in 41 women undergoing in vitro fertilization (IVF). RESULTS: A significant association was found between presence of bacterial antibodies in serum and IgA anti-HSP60 in follicular fluid. CONCLUSIONS: Chlamydia trachomatis infection might be triggering an autoimmune process that could negatively affect the success of IVF.  相似文献   
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