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991.
Vincent Williams Nicholas H. de Klerk Darrell Whitaker A. William Musk Keith B. Shilkin 《American journal of industrial medicine》1995,28(4):489-495
A series of 206 necropsies in Western Australia (WA) have had routine counts made of asbestos bodies in samples of lung tissue using conventional light microscopy. Thirty-two cases had worked in the asbestos industry at Wittenoom, WA and (log) counts of asbestos bodies in their lung tissue correlated well with estimates of their (log) cumulative airborne exposure to crocidolite fibers (r = 0.60). There was no association between the number of asbestos bodies and time since exposure to asbestos ceased. In subjects without known exposure to asbestos, there was a weak but nonsignificant increase in number of asbestos bodies with increasing age, with 26% of cases having no asbestos bodies present. It is concluded that the relatively simple technique of light microscopy for counting of asbestos bodies in lung tissue provides a reliable indication of the level of past occupational exposure to crocidolite in subjects whose exposure has been only to crocidolite. This could be extremely useful in follow-up studies of cohorts that lack reliable measures of airborne exposure to crocidolite asbestos. 相似文献
992.
The Sendai virus V protein, which is a fusion of the P and V ORFs of the P gene, was characterized with antisera to a portion of the V ORF and compared to the P protein. The only property found in common with P is that V is also highly phosphorylated, and this is so even when these proteins are expressed independently of the other viral proteins. Otherwise, V was not found in virions, was not strongly associated with viral nucleocapsids like P, and anti-V had no effect on viral RNA synthesis in vitro under conditions where anti-P was highly inhibitory. The available evidence suggests that V may play a role in RNA synthesis, but it is not an essential one like that of the P protein. 相似文献
993.
M. A. Barnadas M. Alegre E. Baselga L. Randazzo N. Margall N. Rabella R. Curell J. M. de Moragas 《Journal of cutaneous pathology》1997,24(8):507-510
The histopathological changes observed in the cutaneous rash of three patients who suffered the acute phase of HFV infection are described. In all three patients a perivascular and interstitial inflammatory infiltrate was present in the upper and mid-reticular dermis. In one biopsy isolated areas of epidermal necrosis were observed and in the two other biopsies a perifollicular inflammatory infiltrate was detected with perforation in one case. Furthermore, a periductal infiltrate was observed in one of these biopsies. 相似文献
994.
Elaborating on the five-dimensional structure of illness representation, as described in the self-regulation model of Leventhal (1980), the present study is aimed at identifying the relevance of this generic structure for two chronic illnesses: chronic fatigue syndrome (CFS) and Addison's disease (AD). Factor analyses showed the importance of the five dimensions identity, time-line, control/cure, cause, and consequences to differ according to the type of disease. That is, the items representing the five dimensions merged together for CFS patients and AD patients in a different manner and thereby produced different factor solutions for the two patient groups. In CFS patients, a four-factor solution was identified with manageability, seriousness, personal responsibility, and external cause as the factors. In AD patients a four-factor solution was also identified but with seriousness, cause, chronicity, and controllability as the factors. The value of these findings for our understanding of the disease-specific nature of illness representation is discussed. 相似文献
995.
S de Rave H M Goldschmidt B Bravenboer O J Loosveld J H Lockefeer 《The Netherlands journal of medicine》1991,39(3-4):131-135
In order to determine which factors predict the outcome of short term antithyroid drug treatment we studied 42 patients with diffuse goitre in whom 43 instances of thyrotoxicosis were treated. Treatment duration ranged from 24 to 61 wk (median 30 wk). All patients received high-dose carbimazole and thyroid hormone substitution. Patients in remission were followed for 39 to 134 wk (median 73 wk). The relapse rate at 1 yr and at 2 yr after cessation of antithyroid drug treatment was 51%. Of the parameters studied presence or absence of eye signs and initial serum levels of thyroxine, triiodothyronine and immunoglobulin-G in the relapse group and in the remission group showed significant differences in univariate analysis. No significant differences were found for age, sex, family history of thyroid disease, thyroid gland volume or TSH-receptor stimulating autoantibodies. Linear discriminant analysis shows that of the four remaining factors thyroxine is not important in separating both groups. Cox analysis yields only initial serum triiodothyronine and eye signs as significant prognostic factors. With these two factors 18 out of 23 predictions of remission and 16 out of 18 predictions of relapse in the 41 patients with known initial serum triiodothyronine concentrations are correct. Such predictions can be used in the choice of therapy, short-term medical treatment for patients with a low risk and long-term medical treatment or, at the appropriate time, a destructive form of therapy for patients with a high risk of relapse. 相似文献
996.
J B Schutte J de Jong E J van Weerden S Tamminga 《The British journal of nutrition》1992,68(1):195-207
The pentose sugar L-arabinose is one of the most abundant components released by complete hydrolysis of non-starch polysaccharides of feed ingredients of vegetable origin. Two studies were conducted to investigate the apparent ileal digestibility and urinary excretion of L-arabinose at dietary inclusion levels of 50 and 100 g/kg, and 25, 50, 75 and 100 g/kg respectively, in pigs. As a reference, D-glucose was included in the studies. Water intake, ileal flow of volatile fatty acids and ileal and faecal digestibilities of dietary nutrients in pigs fed on the different diets were also examined. Castrated pigs were prepared with a post-valvular T-caecum cannula to measure ileal digestibility. Faecal digestibility was measured in non-cannulated pigs. Apparent ileal digestibility of L-arabinose was found to be approximately 70%. The presence of L-arabinose in the diet increased ileal flow of volatile fatty acids and lactic acid, suggesting the occurrence of microbial degradation of L-arabinose in the pig small intestine. L-arabinose was partly excreted in the urine. The extent of this urinary excretion as a percentage of intake increased linearly (P < 0.01) as the dietary level increased. In pigs fed on the 25 g L-arabinose/kg diet, 10.9% of the L-arabinose consumed appeared in the urine. This level was increased to 14.7% when pigs were fed on a diet containing 100 g L-arabinose/kg diet. Faecal digestibility and retention of nitrogen decreased significantly in pigs fed on the L-arabinose diets. 相似文献
997.
F. Oner L. Ramos R. Simmermacher P. Kingma C. Diekerhof W. Dhert A. Verbout 《European spine journal》2002,11(3):235-245
Reproducibility of fracture classification systems in general has been a matter of controversy. The reproducibility of spinal fracture classifications has not been sufficiently studied. We studied the inter-observer and intra-observer reproducibility of the Magerl (AO) classification using radiograms, CTs and MRIs of 53 patients. We compared this classification with the older and simpler Denis classification. Five observers classified the fractures, first using the radiograms and CTs and, 6 weeks later, with radiograms and MRIs. Three of the observers repeated the readings after 3 months. Three observers also classified the fractures according to Denis. Agreement was measured using Cohen's kappa test. The type (A, B, C) classification of the AO system was fairly reproducible with CTs. With MRI this was only moderate. Group subclassification of the types yielded higher kappa values, corresponding to substantial agreement. The agreement was, in general, better with the Denis classification, but the variance was higher due to the difficulty of finding proper categories for some injury patterns. Although the AO classification allows proper registration of all kinds of injury, the reproducibility, especially at the type level, is problematic. Use of MRI and better definition of the distinctive properties of the three different types may enhance the reproducibility of the scheme. 相似文献
998.
SRR-SB3, a disulfide-containing macrolide that inhibits a late stage of the replicative cycle of human immunodeficiency virus. 下载免费PDF全文
999.
1000.
BACKGROUND--The burden and determinants of airway disease in the population of southern Africa, which is currently undergoing rapid, often uncontrolled, urbanisation and industrialisation, are unknown. Previous surveys have focused on specific occupational groups and few have included women. This paper describes the respiratory status in a 30% probability sample of 206 men and 203 women drawn from an urban black Johannesburg workforce of almost 1500, all working for an educational institution. METHODS--Subjects answered a respiratory questionnaire and performed spirometric tests. Symptom rates and age and height standardised forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC%, and forced expiratory flow (FEF25-75) were analysed by gender in relation to smoking, past work exposures, past and recent respiratory conditions, and socioeconomic indicators. RESULTS--Symptom prevalence was high, bronchitic symptoms in men being related to smoking and previous occupational exposure, and in women to smoking despite the low intensity of their habit. Phlegm and wheezing were related to childhood respiratory illness in both men and women. FVC and FEV1, based on all subjects including smokers, were higher than previously reported for black residents of southern Africa. FVC was also positively related to education and job category. Higher values for ever smokers than for never smokers suggested health selection into the habit, while significant negative smoking effects were seen only on FEV1/FVC% and only in women. CONCLUSIONS--Despite the high prevalence of symptoms--some smoking related--in this urban workforce, lung function levels were higher than previously reported in African blacks, and may reflect improving socioeconomic conditions. 相似文献