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71.
Nitric oxide (NO) is produced in the upper and lower respiratory tract and can be detected in exhaled air of both healthy
individuals and subjects with pulmonary diseases. Recent studies have shown that exhaled NO is mainly derived from the upper
airways. There is, however, evidence that in aqueous solutions NO is rapidly converted to distinct oxides of nitrogen. We
therefore studied the stable NO metabolites nitrate and nitrite in broncho-alveolar lavage (BAL) fluid and serum as indicators
of NO formation in the lower respiratory tract. The study population consisted of 31 healthy children undergoing elective
surgery for nonpulmonary illnesses and 13 immunosuppressed children with pneumonia. Nitrate and nitrite were determined photometrically.
Nitrate was found in BAL fluid of all children. In children with pneumonia, nitrate concentrations in BAL fluid were significantly
higher than in healthy children. A significant correlation was observed between nitrate in BAL fluid and serum of immunosuppressed
children with pneumonia. Nitrite was not detected in any of the BAL fluid or serum samples.
Conclusions Our results suggest that in the lower airways significant amounts of NO are metabolised to nitrate. Studies on NO in pulmonary
diseases should therefore include determination of nitrate in lower airway fluids.
Received: 21 August 1996 / Accepted: 12 December 1996 相似文献
72.
JP Bound PW Harvey BJ Francis F Awwad AC Gatrell 《Archives of disease in childhood》1997,76(2):107-112
OBJECTIVE: To analyse the prevalence of neural tube defects in small geographical areas and seek to explain any spatial variations with reference to environmental lead and deprivation. SETTING: The Fylde of Lancashire in the north west of England. DESIGN: Cases were ascertained as part of a prospective survey of major congenital malformations in babies born in the Fylde to residents there between 1957 and 1981. A matched case-control analysis used infants with cardiovascular system, alimentary tract, and urinary system malformations as controls. Conditional logistic regression was used to assess the effects of more than 10 micrograms/l lead in drinking water and the Townsend deprivation score. RESULTS: The prevalence of neural tube defects in 1957-73 was higher in Blackpool, Fleetwood, and North Fylde, whereas the three control groups showed no significant spatial variation. In 1957-81 mothers living in electoral wards with either a higher proportion of houses with more than 10 micrograms/l lead in the water or a higher deprivation score had a greater risk of having a baby with a neural tube defect. For spina bifida and cranium bifidum alone, this was also true. For anencephaly, deprivation was less important although the effect of lead was still seen. In some neural tube defects, lead may act independently of other possible factors associated with deprivation. It seemed unlikely that lead levels changed significantly during the survey. The percentage of houses with 10 micrograms/l or more of lead in the water in 1984-5 was similar to that found in Great Britain 10 years previously. CONCLUSION: There is evidence to suggest that lead is one cause of neural tube defects, especially anencephaly. This could link the known preventive actions of hard water and folic acid. Calcium is a toxicological antagonist of lead. One cause of a deficiency of folic acid is impaired absorption secondary to zinc deficiency, which may be produced or exacerbated by lead. 相似文献
73.
74.
FJ O'Callaghan AC Clarke H Joffe B Keeton R Martin A Salmon RD Thomas JP Osborne 《Archives of disease in childhood》1998,78(2):159-162
This report highlights the association between tuberous sclerosis and Wolff-Parkinson-White syndrome. Ten patients with concurrent diagnoses of Wolff-Parkinson-White syndrome and tuberous sclerosis were identified. Wolff-Parkinson-White syndrome presented early in life, nine cases being diagnosed in the first year. Eight of the 10 cases were male. In eight cases, the syndrome was associated with supraventricular tachycardias, and in nine with cardiac rhabdomyomata. One child died from cardiac failure secondary to obstruction of the left ventricular outflow tract by a rhabdomyoma. Five of nine survivors showed resolution of Wolff-Parkinson-White syndrome on follow up. The accessory pathway was localised in nine patients from surface electrocardiograms: six children had left sided pathways and three had right sided pathways. 相似文献
75.
M. C. J. Kneyber A. H. Brandenburg R. de Groot K. F. M. Joosten P. H. Rothbarth A. Ott H. A. Moll 《European journal of pediatrics》1998,157(4):331-335
Respiratory syncytial virus (RSV) infections are characterized by upper or lower respiratory tract symptoms including bronchiolitis
and pneumonia. Apnoea may be the first sign of disease in children with RSV infection. The aims of this study were the identification
of independent risk factors for RSV associated apnoea and the prediction of the risk for mechanical ventilation in children
with RSV associated apnoea. Medical records of children younger than 12 months of age admitted with RSV infection between
1992 and 1995 to the Sophia Children's Hospital, were reviewed. Demographic parameters, clinical features and laboratory parameters
(SaO2, pCO2 and pH) were obtained upon admission and during hospitalization. Children with and without apnoea were compared using univariate
and multivariate logistic and linear regression analysis. One hundred and eighty-five patients with RSV infection were admitted
of whom 38 (21%) presented with apnoea. Patients with apnoea were significantly younger, had a significantly lower temperature,
higher pCO2 and lower pH and had on chest radiographs also more signs of atelectasis. The number of patients admitted to the ICU because
of mechanical ventilation and oxygen administration was significantly higher in children with RSV associated apnoea. Apnoea
at admission was a strong predictor for recurrent apnoea. The relative risk for mechanical ventilation increased with the
number of episodes of apnoea: 2.4 (95% CI 0.8 – 6.6) in children with one episode of apnoea (at admission) versus 6.5 (95%
CI 3.3 – 12.9) in children with recurrent episodes of apnoea.
Conclusions Age below 2 months is the strongest independent risk factor for RSV associated apnoea. Apnoea at admission increases the
risk for recurrent apnoea. The risk for mechanical ventilation significantly increases in children who suffer from recurrent
apnoea.
Received: 12 May 1997 / Accepted in revised form: 22 August 1997 相似文献
76.
David AC Leggett Kenneth A Miles Benjamin B Kelley 《Journal of Medical Imaging and Radiation Oncology》1998,42(4):335-340
Five cases of cerebral glioma are presented here that illustrate the benefit of functional CT imaging of blood-brain barrier permeability and cerebral blood volume. Functional CT uses Patlak analysis of a single location dynamic sequence to extract physiological information that is useful clinically in the assessment of cerebral gliomas. Functional CT offers distinct advantages over other functional modalities including clearer delineation of tumour, tumour grading, measurement of tumour activity and monitoring response to therapy. 相似文献
77.
Haberham ZL van den Brom WE Venker-van Haagen AJ de Groot HN Baumans V Hellebrekers LJ 《Brain research》2000,873(2):287-290
We investigated whether components from the rat Vx-MLAEP could be used to assess depth of anaesthesia induced by propofol. Propofol decreased MLAEP amplitudes and increased latencies. We propose that the P(16)-N(22) wave in the rat MLAEP is similar to the human P1, and that recovery of this wave during propofol anaesthesia correlates with behavioural measures of the regaining of consciousness. 相似文献
78.
背景:家族性高胆固醇血症儿童往往存在内皮功能异常和颈动脉内膜中层厚度(intima—media thickness,IMT)增加,预示这类患儿未来有可能早发动脉粥样硬化性疾病。虽然针对这种疾病的病因干预治疗已开展十余年,但是目前尚无研究对儿童应用降胆固醇药物的长期疗效和安全性进行评价。
目的:评价家族性高胆固醇血症儿童应用普伐他汀(pravastatin)治疗2年的疗效及安全性。
设计:本随机、双盲、安慰剂对照试验于1997年12月7日至1999年10月4日入选儿童,随访2年。
地点及参试者:214名8~18岁家族性高胆固醇血症儿童均来自荷兰一家医疗救治中心。
干预:限制患儿脂质摄入并鼓励开展日常体育锻炼,随后患儿随机分配接受20~40mg/d普伐他汀治疗(n=106)或安慰片剂治疗(n=108)。主要观察指标:疗效的评价指标是2年后两组患儿颈动脉IMT平均值的变化;安全性的评价指标为2年后患儿生长发育成熟情况、激素水平以及肌肉和肝脏酶的变化。
结果:与基线相比,普伐他汀组颈动脉IMT呈现出减小的趋势(均值[SD],-0.010[0.048]mm;P=0.049),而安慰剂组呈现出增厚的趋势(均值[sD],+0.005[0.044]mm;P=0.28)。两组问IMT的均值(sD)变化(0.014[0.046]mm)具有品著性(P=0.02)。另外,与安慰剂组相比,普伐他汀组低密度脂蛋白胆固醇的平均水平显著降低(分别为-24.1%和+0.3%;P〈0.001)。两组间生长发育、肌肉或肝脏酶、内分泌功能指标、Tanner阶段评分、月经初潮和睾丸体积均无差异。
结论:采用普伐他汀治疗家族性高胆固醇血症患儿2年后颈动脉粥样硬化明显减退,药物对生长发育、性器官成熟、激素水平和肌肉、肝脏组织无副作用。 相似文献
79.
Postnatally, the stepping response can be elicited right after birth, but soon diminishes and disappears by about 2-3 months of age. It is still not clear if the disappearance of the response is caused by gradual maturation of the central nervous system, environmental factors, or biomechanical factors such as added body weight and/or increased muscle mass of the legs. This clinical study assessed the stepping response in a group of healthy infants (n = 58) at the age of 6 weeks: 37 born preterm and corrected for gestational age. Quantitative measures of stepping response were obtained together with the qualitative measures of behavioural state and the distribution of active and passive muscle power of the legs. Mechanical factors were studied by dividing the infants according to their birth weight status, and calculating the ponderal index (PI), leg volume (LV), and weight gain of each group. Preterm infants show more stepping responses, more muscle power discrepancies, and different leg volumes than their full-term counterparts. In addition, our results reported significant relationship between gestational age and relative birth weight on the manifestation of stepping response. Within the preterm group the responses lingered longer in infants with shorter gestational ages and in those with lower birth weight status. Consequently, this study suggests that environmental experience and the time of birth of the infants play a more significant role than maturation and mechanical factors in the manifestation of the infantile stepping response. 相似文献
80.
BACKGROUND: A randomized, double-blind, multi-center trial was started to compare the severity of extrapyramidal symptoms (EPS) during risperidone and haloperidol treatment in schizophrenic patients who had disturbing EPS during their previous neuroleptic treatment. Additional objectives of this trial were comparing the antipsychotic effectiveness of the two treatments and the use of antiparkinsonian medication. METHODS: Effects of flexible doses of risperidone and haloperidol were compared in 77 psychotic patients (83% with chronic schizophrenia) with disturbing neuroleptic-induced EPS (risperidone 40 patients, haloperidol 37). The trial was completed by 47 patients: 25 in the risperidone group (12 women, 13 men), and 22 in the haloperidol group (10 women, 12 men). RESULTS: An adequate antipsychotic effect was obtained in most patients by both treatments. The primary aim of this trial was comparing parkinsonism measured with the extrapyramidal syndrome rating scale (ESRS) during treatment with risperidone and haloperidol. Two primary parameters were selected: the change from baseline to the worst score during treatment of ESRS II (parkinsonism) and ESRS VI (clinical global impression of severity of parkinsonism). The CGI of severity of parkinsonism was better with risperidone (P=0.025), while the parkinsonism total score tended to be better with risperidone (P<0. 10). Before the double-blind treatment, 34 (of the 77) had used antiparkinson medication (risperidone 18, haloperidol 16). During the double-blind treatment phase, 21 patients had used antiparkinson medication (risperidone 11, haloperidol 10). The larger reduction of parkinsonism in the risperidone group was not due to a difference in the use of anti-parkinsonian medication. CONCLUSIONS: In this group of schizophrenic patients with disturbing EPS during previous neuroleptic treatment, a stronger reduction of parkinsonism was observed with risperidone than with haloperidol. 相似文献