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131.
A study to discriminate among different possible sources of elevated Pb exposure for American woodcock (Scolopax minor) in eastern Canada is described. Undamaged wing bones excised from young-of-the-year woodcock collected from several locations in southern Ontario, southern Quebec, New Brunswick, and Nova Scotia, Canada, along with soil and earthworm (Aporrectodea tuberculata and Lumbricus rubellus) samples from the same sites, were analyzed for total Pb, and stable Pb isotopes. Ignoring six soil samples with high (> 60 microg/g) Pb concentration from the vicinity of Montreal (QC, Canada), the mean soil-Pb concentration for all sites combined was 19 microg/g (dry wt; n = 64), with a mean 206Pb:207Pb ratio of 1.19, values typical for uncontaminated rural soils in eastern North America. In earthworms, Pb concentrations ranged from 2.4 to 865 (microg/g [dry wt], mean = 24 microg/g). Concentrations of Pb in worms and soils were positively correlated (r = 0.71; p < 0.01), and 206Pb:207Pb ratios for worms and soils were also positively correlated (r = 0.54; p < 0.05). However, most young-of-the-year woodcock with high bone-Pb accumulation (> 20 microg/g) had 206Pb:207Pb ratios substantially different from worms and soils sampled from the same areas, even though woodcock feed extensively on soil invertebrates, especially earthworms. The range of 206Pb:207Pb ratios in wing bones of woodcock with elevated Pb exposure was not consistent with exposure to environmental Pb from past gasoline combustion nor Precambrian mining wastes but was consistent with ingestion of spent Pb shotgun pellets.  相似文献   
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Autologous stem cell transplantation (ASCT) has been proposed as a possible treatment for severe autoimmune diseases such as rheumatoid arthritis (RA), multiple sclerosis (MS), systemic sclerosis, and systemic lupus erythematosus (SLE). To date, more than 250 patients with various autoimmune disorders have undergone an ASCT since 1996. Among them, there is a very limited number of children. This review summarizes the experience with ASCT for pediatric rheumatic diseases. Most reported cases concern juvenile idiopathic arthritis (JIA). Experience with ASCT for childhood SLE, Scleroderma, or Dermatomyositis is very limited. To date, 12 children with severe systemic or polyarticular JIA, all with progressive disease activity despite the use of corticosteroids, MTX, CsA, or Cyclophosphamide were treated in our center with ASCT. Rheumatologic follow-up at 3-month intervals up to 36 months showed a marked decrease in arthritis severity as expressed by the core-set criteria for juvenile chronic arthritis (JCA) activity. However, these children remain at risk for severe viral infections due to the prolonged lymfopenia. ASCT in this severely ill patient group induces a very significant and drug-free remission of the disease, but carries a significantly risk of developing fatal MAS.  相似文献   
134.
目的:测定NT-3cDNA/CHO细胞表达的基因重组NT-3的生物学活性。方法:体外培养8日龄鸡胚背根神经节(DRG),加入条件培养基,测量背根节神经突起生长的长度。结果:NT-3cDNA/CHO细胞培养48h后的无血清条件培养基1:24稀释后即能促进DRG神经突破的生长;随着其中NT-3浓度增加,神经突破长度也逐渐延长,有明显的量效关系;DRG培养48h长出的神经突破与24h相比,明显长而致密;  相似文献   
135.
结合国内外文献,简介抗病毒新药万乃洛韦的药理特性、临床应用、不良反应及用法和剂量。  相似文献   
136.
Gamma knife was installed at the PD Hinduja National Hospital and Medical Research Centre, Mumbai, India, in January 1997. In the first year of gamma-knife radiosurgery to January 1998, we treated 110 patients, of whom six had medically refractory trigeminal neuralgia. Seven treatments were administered to this group of six patients (one had bilateral neuralgia). This report evaluates the effectiveness of radiosurgery treatment in these patients. The median age of the patients was 56 years and there were five males and one female. Following Leksell stereotactic frame fixation, a magnetic resonance imaging scan was done in all. The Leksell gamma plan was used for planning. A radiosurgery dose of 70–80 Gy was delivered to the trigeminal root entry zone, 2–4 mm anterior to the junction of the pons and trigeminal nerve with a single 4 mm collimator helmet. Complete pain relief was achieved in four patients. Two had partial relief. No patient developed any radiosurgery related morbidity during the follow-up period of 5–16 months. Radiosurgery seems to be an effective approach for medically or surgically refractory trigeminal neuralgia.  相似文献   
137.
Three children with azotaemic renal osteodystrophy were treated with 1,25-dihydroxycholecalciferol (1,25(OH)2D3). All showed clinical, biochemical, and radiological improvement within 6 months of starting treatment. There were no complications. The dose of 1,25(OH)2D3 required was 0-5 microgram per day for 2 children aged 22 and 30 months, and 2 microgram per day for a 15-year-old boy. 2 of the patients were receiving phenobarbitone and phenytoin and in one of them prior treatment with dihydrotachysterol 0-5 mg daily and 6 microgram 1alpha-hydroxycholecalciferol (1alphaOHD3) daily had failed to induce improvement. In one patient, in whom serial iliac bone samples were available, 2 microgram 1,25(OH)2D3 resulted in histological improvement in previously severe osteomalacia. 1,25(OH)2D3 appears to be an effective and safe drug in the treatment of uraemic osteodystrophy.  相似文献   
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139.
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.  相似文献   
140.
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