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1.
Abstract: This study reports on an analysis of the lead concentrations in 123 venous blood samples collected from Perth children aged between two months and 17 years attending Princess Margaret Hospital. The overall geometric mean was 6.9 μg lead per 100 ml whole blood, with 95 per cent of results lying between 3.2 and 14.8 μg/100 ml. Among children under five years of age, those aged between 18 months and two years had the highest geometric mean blood lead (11.1 μg/100 ml). There were no consistent associations between geometric mean blood lead and area of residence, age group or sex. In this sample of Perth children, the mean blood lead concentration was lower than those reported in other studies. Less than 0.1 per cent of children of the age range studied would have been expected to have lead levels exceeding the NHMRC ‘level of concern’ (25 μg/100 ml) current at the time of the study. However, the recent adoption of goal of less than 10 μg/100 ml could mean that lead levels in up to 21 per cent of Perth children would now be regarded as excessive.  相似文献   
2.
Giant serpentine aneurysms form a subgroup of giant intracranial aneurysms with specific radiological and surgical features. Previous reports have stressed the predilection of these lesions for the carotid circulation, particularly the middle cerebral artery. Two cases of serpentine aneurysm affecting the posterior circulation are reported and the problems of diagnosis and treatment of this lesion are discussed.  相似文献   
3.
Retrorenal colon: implications for percutaneous diskectomy   总被引:1,自引:0,他引:1  
Helms  CA; Munk  PL; Witt  WS; Davis  GW; Morris  J; Onik  G 《Radiology》1989,171(3):864-865
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary.  相似文献   
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采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。  相似文献   
8.
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
9.
AIM: The aim of this pilot study was an investigation on photodynamic therapy (PDT) whether it is a good alternative for treating periungual and subungual warts of the hands. STUDY DESIGN: Twenty patients (mean age: 30.5 years) with a total of 40 periungual and subungual warts were treated with PDT. A photosensitizer, 20%delta-aminolevulinic acid was applied on the warts. After a mean incubation time of 4.6 h (SD: 1.2), the warts were irradiated with the VersaLight for 5-30 min (15.2 +/- 4.3 min). RESULTS: After a mean of 4.5 treatments a mean clearance of 100% was achieved in 90% of the patients. One patient (5%) showed a clearance of 50% and another showed no improvement. The subungual or periungual location of the wart had no influence on the number of treatments or end result (P > 0.05). There were two recurrences during the mean follow-up period of 5.9 months (SD: 7.6). Besides mainly pain and hyperpigmentation, most treatments had no side-effects. CONCLUSION: PDT can offer a good alternative for treating periungual warts of the hands. Larger studies are indicated.  相似文献   
10.
Previous work has suggested that there may be a widespread disturbance of motor control mechanisms in patients with cervical dystonia. In the present study, we used transcranial magnetic stimulation to investigate the topography of the corticomotor projection to the abductor pollicis brevis (APB) muscle in 10 subjects with idiopathic torticollis. Threshold-adjusted stimuli were delivered at multiple scalp sites during a low-level voluntary contraction of the APB, and maps were generated of motor evoked potential amplitude versus scalp site. The cortical maps for the APB on the side opposite to the direction of head rotation were displaced laterally or posteriorly in all subjects and reverted to a more normal position after botulinum toxin injection of the cervical muscles in 5 subjects. The findings point to a reversible reorganisation of the corticomotor representation of the hand on the same side as the sternocleidomastoid (SCM) muscle that is involved in producing the dystonia. These results provide further evidence for the involvement of cortical centres and for a more widespread abnormality of motor control mechanisms in focal dystonia. The findings also support the notion that head turning is chiefly mediated by the hemisphere ipsilateral to the direction of the head rotation by means of a corticomotor projection to the contralateral SCM.  相似文献   
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