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71.
Within a randomized European multicentre trial the time of onset, severity and progression of intracerebral haemorrhages (ICH) were investigated prospectively by serial cranial ultrasonography in 343 ventilated infants with severe respiratory distress syndrome (RDS) following instillation of single or multiple doses of a natural porcine surfactant (Curosurf). In 148/343 infants (43%) ICH was diagnosed (grade I or II: 22%, grade III or IV: 21%). In 26 cases (8%) ICH was present on the ultrasound scan prior to surfactant instillation at a median age of 6h. Incidence and severity of ICH was similar after single- or multiple-dose surfactant treatment. Using a logistic regression model the following risk factors predictive of ICH were defined: low birth weight, allocation to certain hospitals, vaginal delivery, Apgar score6, rectal temperature on admission 36°C, primary anaemia, acidosis prior to treatment, RDS grade IV in pre-treatment chest films and poor response to surfactant treatmentOur study provides supportive evidence that multiple doses of Curosurf do not increase the risk for ICH as compared to single-dose administration.A preliminary report of this work was presented at 8th International Workshop on Surfactant Replacement, Oslo, Norway, May 21 1993. The study was supported by grants of the German government (BMFT 93 607 27) and the German Research Council (Deutsche Forschungsgemeinschaft He 2072: 1–2). The surfactant used in the trial was prepared ang tested in Stockholm with the skilful technical assistance of Elin Arvesen, Bim Linderholm. Eva Lundberg, Gunhild Nilsson and Petru Popa (supported by the Swedish Medical Research Council (Project No. 3351) and Oscar II:s Jubileumsfond)Dedicated to the memory of Edgar (Eddi) Laufkötter, one of the most active trial collaborators, who died under tragic circumstances on April 10, 1994.  相似文献   
72.
The objective of the National Human Exposure Assessment Survey (NHEXAS) in Arizona is to determine the multimedia distribution of total human exposure to environmental pollutants in the classes of metals, pesticides, and volatile organic compounds (VOCs) for the population of Arizona. This was accomplished by studying a probability-based sample of the total population in Arizona with a nested design for the different stages of sampling (954 Stage I, 505 Stage II, and 179 Stage III participants). This report compares the study population demographics with those from the U.S. Census and provides preliminary data on the distributions of the example pollutant for each class, lead for metals, chlorpyrifos for pesticides, and benzene for metals. The probability-based sample age and gender demographics compare reasonably well with the Census data (1990 Census and 1996 Census Estimate). The race/ethnicity compared less well with 21% Hispanics in the 1996 Census Estimate and 42% Hispanics in the entire NHEXAS-Arizona sample and 30% Hispanics as Stage III participants for this study. The chemical analyses of the various media (yard soil, foundation soil, house dust, indoor air, outdoor air, drinking water, food, and beverage) show generally low levels of the representative pollutants. The 50th percentiles of the distributions are generally near or below the analytical detection limits, and applicable Federal action limits were rarely exceeded.  相似文献   
73.
A modern malaise   总被引:1,自引:0,他引:1  
JS Robertson Dr   《Public health》1999,113(4):155-156
  相似文献   
74.
Hebb MO  Robertson HA 《Neuroscience》1999,90(2):423-432
We have investigated the relationship between alterations in neuronal activity in the superior colliculus and behavioral responses which occur following disruption of basal ganglia circuitry. These changes were analysed following unilateral suppression of the immediate early genes, c-fos and ngfi-a, in the striatum and/or the globus pallidus. Animals with unilateral suppression of immediate early gene expression in the striatum exhibited robust circling activity, following administration of D-amphetamine, that was directed towards the side of suppression. The intensity of rotation was inversely related to the length of the recovery period following antisense infusion and increased significantly when the globus pallidus was infused simultaneously with the striatum. The difference between ipsiversive (towards the antisense-infused hemisphere) and contraversive rotations was calculated and animals were grouped by number according to their ipsiversive bias: I, <50 turns; II, 50-500 turns; III, 500-1000 turns; IV, >1000 turns. Immunohistochemical localization of Fos was used as an indicator of neuronal activity in the superior colliculus. While group I animals showed diffuse Fos-like immunoreactivity throughout the intermediate layers of the superior colliculus, those animals in groups II-IV showed increasing suppression of Fos-like immunoreactivity in the stratum album intermediale and marked enhancement in the stratum griseum intermediale. Correlation and regression analysis revealed a significant positive relationship between the number of ipsiversive rotations and the number of Fos-positive nuclei in the stratum griseum intermediale of the ipsilateral superior colliculus. These data suggest that the degree of rotation elicited in an animal may depend on reciprocal suppression/stimulation of adjacent intermediate strata of the superior colliculus. This study provides the first demonstration, using Fos immunohistochemistry, of changes in tectal activity produced by alterations in basal ganglia function. These findings support previous electrophysiological studies in this region and suggest that the nigrotectal projection may be an important site of altered basal ganglia output.  相似文献   
75.
BACKGROUND: An earlier small-scale study of children with autism revealed that 8.1% of such patients were co-morbid for Gilles de la Tourette syndrome (GTS). The present study is a large scale test of whether this result replicates. METHOD: Four hundred and forty-seven pupils from nine schools for children and adolescents with autism were screened for the presence of motor and vocal tics. RESULTS: Subsequent family interviews confirmed the co-morbid diagnosis of definite GTS in 19 children, giving a prevalence rate of 4.3%. A further 10 children were diagnosed with probable GTS (2.2%). CONCLUSIONS: These results indicate that the rate of GTS in autism exceeds that expected by chance, and the combined rate (6.5%) is similar to the rates found in the smaller-scale study. Methodological considerations and alternative explanations for an increased prevalence are discussed.  相似文献   
76.
BACKGROUND: Current mental health legislation in the UK makes provision for the use of certain treatments in severely ill patients who are unable, or unwilling, to give informed consent. Under the terms of this legislation, electroconvulsive therapy (ECT) may be used, usually to treat severely depressed patients. A number of organizations have challenged this practice, stating that ECT should only be given with fully informed consent: it has been implied that patients receiving compulsory ECT (given without the patient's consent, under the terms of mental health legislation) find the treatment damaging and unhelpful. METHODS: A series of 150 patients receiving ECT in Aberdeen was studied. A proportion of the series (approximately 7%) received compulsory ECT. The views and treatment outcomes of compulsory patients were compared with those of patients giving informed consent for treatment. RESULTS: More than 80% of patients in both consenting and compulsory groups considered ECT to have helped them. Clinical outcome did not differ between the groups. Patients' views showed marked concordance with independent medical evaluation of outcome. CONCLUSIONS: Outcome following ECT in non-consenting patients is equivalent to that seen in consenting patients whether rated by the patients themselves or by clinicians. Overall outcome is good, with more than 80% of patients benefiting from treatment. A ban on compulsory ECT would deny the access of seriously ill patients to an effective and acceptable treatment.  相似文献   
77.
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79.
Negative cytology preceding cervical cancer: causes and prevention.   总被引:4,自引:4,他引:0       下载免费PDF全文
AIM--To assess the validity of negative cervical smear reports in women who subsequently developed cervical cancer; and to determine means of improving the screening process. METHODS--One hundred and forty cervical smears, initially reported as negative from 103 women, and taken up to 12 years before diagnosis of cervical cancer, were reviewed. RESULTS--Ninety two smears contained dyskaryotic cells. Analysis showed that these smears formed several well defined patterns. False negative reports were likely to occur if fragments of neoplastic tissue rather than dissociated dyskaryotic cells were present or if the smear contained few dyskaryotic cells. Screening fatigue appeared to be a factor in others. It was also considered important that smears contained cells from the endocervix. These were deficient in 64% of the 47 smears confirmed as negative on review and in 69% of smears containing only a few dyskaryotic cells. CONCLUSIONS--Current methods of quality assurance will not remedy these defects in the screening process. It is the responsibility of laboratories to identify sources of poor smears and liaise with smear takers to ensure an improvement in quality. Assessment of the quality of smears received by a laboratory should become an important part of audit. Staff training should place more emphasis on the interpretation of "microbiopsies". The adoption of a quick scanning technique before conventional screening would probably also substantially reduce false negative results.  相似文献   
80.
Risk factors in calcium stone disease of the urinary tract.   总被引:13,自引:0,他引:13  
The concept that calcium stone formation may be explained on the basis of a number of risk factors is developed. The main risk factors involved are shown to be calcium, oxalate, pH, acid mucopolysaccharides and uric acid. A method is described for calculating and combining the individual risk factors into a measure of the "relative probability" of forming stones (PSF). PSF values are generally lower in normal subjects than in stone-formers. Amongst the normals, PSF values are lower in children and women than in men. Recurrent stone-formers have the highest PSF values and these correlate well with the severity of the diseases as defined by the stone episode rate of the patient. Single stone-formers have PSF values intermediate between those of normal men and those of recurrent stone-formers.  相似文献   
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