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排序方式: 共有862条查询结果,搜索用时 15 毫秒
51.
Gillman MW Rich-Edwards JW Rifas-Shiman SL Lieberman ES Kleinman KP Lipshultz SE 《The Journal of pediatrics》2004,144(2):240-245
OBJECTIVE: To investigate perinatal predictors of newborn blood pressure. STUDY DESIGN: Among 1059 mothers and their newborn infants participating in Project Viva, a US cohort study of pregnant women and their offspring, we obtained five systolic blood pressure readings on a single occasion in the first few days of life. Using multivariate linear regression models, we examined the extent to which maternal age and other pre- and perinatal factors predicted newborn blood pressure level. RESULTS: Mean (SD) maternal age was 32.0 (5.2) years, and mean (SD) newborn systolic blood pressure was 72.6 (9.0) mm Hg. A multivariate model showed that for each 5-year increase in maternal age, newborn systolic blood pressure was 0.8 mm Hg higher (95% CI, 0.2, 1.4). In addition to maternal age, independent predictors of newborn blood pressure included maternal third trimester blood pressure (0.9 mm Hg [95% CI, 0.2, 1.6] for each increment in maternal blood pressure); infant age at which we measured blood pressure (2.4 mm Hg [95% CI 1.7, 3.0] for each additional day of life); and birth weight (2.9 mm Hg [95% CI, 1.6, 4.2] per kg). CONCLUSIONS: Higher maternal age, maternal blood pressure, and birth weight were associated with higher newborn systolic blood pressure. Whereas blood pressure later in childhood predicts adult hypertension and its consequences, newborn blood pressure may represent different phenomena, such as pre- and perinatal influences on cardiac structure and function. 相似文献
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Flunisolide hydrofluoroalkane (HFA) has efficacy equivalent to that of flunisolide chlorofluorocarbon (CFC) at one third the dose of the CFC formulation, a reduction from 250 microg/puff for flunisolide CFC to 85 microg/puff for flunisolide HFA. Flunisolide HFA delivers a smaller particle size (1.2 microm) in solution, resulting in improved lung deposition as compared with flunisolide CFC (3.8 microm), which is delivered in suspension. An added built-in spacer has reduced oropharyngeal deposition that may result in fewer adverse events and make it easier to use. The objective of this study was to compare the year-long safety of flunisolide HFA (daily dosage 340 microg) with that of CFC beclomethasone dipropionate (BDP) (daily dosage 336 microg) and cromolyn sodium (daily dosage 6,400 microg) in children 4-11 years old with mild-to-moderate asthma. The effects of these drugs on linear growth and growth velocity were also compared. The study was a 1-year open-label, parallel-group trial. Changes in physical examinations (including growth), adverse events, vital signs, electrocardiograms, cosyntropin stimulation tests, mouth and throat cultures for Candida albicans, and laboratory findings were analyzed. Patients 4-5 years old received flunisolide HFA only. In total, 235 children were evaluated (152 receiving flunisolide HFA, 39 BDP, and 44 cromolyn). The incidence of adverse events was comparable among treatment groups; most were mild or moderate and considered unrelated to treatment. Among patients 6-11 years old, mean changes from baseline height at week 52 were 6.2 cm for the flunisolide HFA and cromolyn groups and 5.1 cm for the BDP group. Thus growth in children receiving flunisolide HFA was unaffected by 1 year of treatment. Changes from baseline in other parameters, including response to cosyntropin stimulation, were insignificant and similar among the 3 treatment groups. At the dosages studied, and following 1 year of treatment, flunisolide HFA with its small particle size and built-in spacer is safe and well tolerated in children 4-11 years old. There are no adverse effects associated with hypothalamic pituitary axis (HPA) function of flunisolide HFA, including linear growth in children 6-11 years old when compared with BDP and cromolyn sodium. 相似文献
56.
Butler MW Mullan RH Schaffer KE Crotty TB Luke DA Donnelly SC 《Irish journal of medical science》2003,172(4):204-205
Background Hydatid disease is rare in Ireland and its incidence and prevalence are unknown. Most cases are diagnosed by a combination
of clinical findings, morphological features on imaging and by serological testing.
Aims We describe an Irish case of pulmonary hydatid disease detected at bronchoscopy by bronchoalveolar lavage, and discuss the
diagnosis and treatment of the disorder. 相似文献
57.
Oxidation of ochratoxin A by an Fe-porphyrin system: model for enzymatic activation and DNA cleavage
Ochratoxin A (OTA, 1) is a fungal toxin that facilitates single-strand DNA cleavage, DNA adduction, and lipid peroxidation when metabolically activated. To model the enzymatic activation of OTA, we have employed the water-soluble iron(III) meso-tetrakis(4-sulfonatophenyl)porphyrin (FeTPPS) oxidation system. In its presence, OTA has been found to facilitate single-strand cleavage of supercoiled plasmid DNA through production of reactive oxygen species (ROS) (i.e., the hydroxyl radical, HO(*)). The reaction of OTA with the FeTPPS oxidation system also generated three hydroxylated products (chlorine atom still attached), which was taken as evidence for production of the known hydroxylated metabolites (2-4) of OTA. This result suggested that the FeTPPS system served as a reasonable model for the enzymatic activation of OTA. When the reaction of OTA with FeTPPS was carried out in the presence of excess hydrogen peroxide (H(2)O(2)) and sodium ascorbate, a hydroquinone species (OTHQ, 5) was detected in which an OH group has replaced the chlorine atom of OTA. The production of OTHQ (5) was dependent on the presence of the reducing agent, sodium ascorbate, which suggested that the oxidation catalyst furnished the quinone derivative OTQ (6) that was subsequently reduced to OTHQ (5) by ascorbate. Utilizing a synthetic sample of OTHQ (5), the hydroquinone was found to undergo autoxidation with a t(1/2) of 11.1 h at pH 7.4, and to possess a pK(a) value of 8.03 for the phenolic oxygen ortho to the carbonyl groups. Our findings imply that the hydroquinone (OTHQ) and quinone (OTQ) metabolites of OTA have the ability to cause alkylation/redox damage and have allowed us to propose a viable pathway for oxidative damage by OTA. 相似文献
58.
The distinction between true and suspected poisoning in children has not been made clear in previous work on childhood poisoning. A study of suspected poisoning in children under 15 years of age in a defined population of North East Bristol from November 1970 to July 1973 carried out by the Health Education Council Medical Research Division included 53,000 child-years at risk. The number of suspected poisonings was 3-4/1000 population aged under 15 years per year, with a higher incidence in younger age groups. Detailed investigation of the circumstances of the accidents carried out by a multidisciplinary team showed that at least 65%, and possibly as many as 78% were poisoning scares and not true poisoning. The evidence used by the casualty doctor and by the parents to diagnose poisoning was explored, and in many cases was circumstantial. Children with fathers in nonmanual occupations were over-represented. This may reflect differences in patterns of utilization behaviour rather than true differences in incidence. 相似文献
59.
A Akbar JHM Rees G Nyamugunduru MW English DA Spencer PH Weller 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(7):783-785
Hypomagnesaemia in children with cystic fibrosis (CF) is under-recognized. We report a child with CF who developed significant hypomagnesaemia following intravenous (i.v.) treatment with aminoglycosides for exacerbations of Pseudomonas aeruginosa infection. Three additional cases have also been observed. Investigations in two patients have revealed excessive renal loss of magnesium. It is postulated that renal tubular damage secondary to the cumulative effects of repeated courses of aminoglycosides resulted in hypomagnesaemia, and we suggest screening for this problem by monitoring serum magnesium regularly in all patients with CF receiving multiple courses of aminoglycosides. 相似文献
60.