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The effect of barium on blood in the gastrointestinal tract 总被引:2,自引:0,他引:2
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A?Salt K?Freeman A?Prusa N?Ferret W?Buffolano G?Malm D?Schmidt HK?Tan RE?GilbertEmail author The European Multicentre Study on Congenital Toxoplasmosis 《BMC pediatrics》2005,5(1):21
Background
We aimed to determine how response to a parent-completed postal questionnaire measuring development, behaviour, impairment, and parental concerns and anxiety, varies in different European centres. 相似文献46.
Voormolen MH Lohle PN Fransen H Juttmann JR de Waal Malefijt J Lampmann LE 《Nederlands tijdschrift voor geneeskunde》2003,147(32):1549-1553
OBJECTIVE: To describe the technique of percutaneous vertebroplasty and the short-term results in patients with symptomatic, osteoporotic vertebral compression fractures. DESIGN: Prospective follow-up study. METHOD: In a pilot-study to evaluate the short-term safety and effectiveness of percutaneous vertebroplasty, 18 consecutive patients with a total of 33 osteoporotic thoracic or lumbar vertebral compression fractures were treated from October 2001 to June 2002 with a follow-up of 3-6 months. The indication for treatment was a symptomatic, therapy-resistant osteoporotic vertebral compression fracture. Percutaneous vertebroplasty was performed under radiographic control, after previous intraossal venography, using bone cement mixed with barium sulphate. Post-procedural follow-up consisted of radiological evaluation with conventional thoracolumbar X-rays and MRI scans, and interviews of the patients. RESULTS: Percutaneous vertebroplasty was technically successful in 31 of 33 vertebral fractures (94%), and in 16 of 18 patients (89%). One patient with extreme venous contrast leakage could not be treated. Sixteen patients had less or no pain after treatment. One patient retained thoracolumbar back pain after inadequate cementations and refused further treatment. None of the patients reported aggravation of symptoms following the procedure. Contrast leakage was absent in 18 vertebrae. In 8 vertebrae there was contrast leakage to paravertebral veins. In three of these cases the leakage was so severe that embolisation was performed, with success in one case. In 13 vertebrae, cement leakage to intervertebral and paravertebral spaces and pedicular cement spurs were seen, without clinical consequences. Immediately after the procedure and during follow-up there were no clinically relevant complications. CONCLUSION: Percutaneous vertebroplasty was a technically feasible treatment in these patients with symptomatic, therapy-resistant, osteoporotic vertebral fractures. The first short-term results were comparable with results in the literature. A prospective randomised intervention study will be needed to compare percutaneous vertebroplasty with optimal conservative treatment. 相似文献
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Patient follow up screening evaluations. Examples with regard to congenital hip dislocation and congenital heart disease
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Juttmann RE Hess J van Oortmarssen GJ van der Maas PJ 《Journal of epidemiology and community health》2001,55(2):126-131
OBJECTIVE: To discuss the merits of the patient follow up study design for the evaluation of some specific mass screening programmes. DESIGN: Theoretical evaluation illustrated by two examples. SETTING: Department of Public Health Erasmus University Rotterdam. MAIN RESULTS: The gold standard for evaluation of favourable effects of screening is the randomised controlled trial (RCT). Application of an RCT, however, is often not feasible, in which cases observational studies will have to be relied on. The case-control study design is generally considered to be second best. In some situations, however, a patient follow up study design may be applicable and may have some major advantages. The use of the patient follow up design for screening evaluation will often be very problematic or even unacceptable, particularly as far as screening for cancer is concerned. The most important objections are resulting from lead time bias, length bias, selection bias and over-treatment bias. For the evaluation of screening for congenital heart disease and congenital hip dislocation in Dutch child health care, however, these objections may relatively simply be overcome. Lead time bias will be of little importance, as the ages of onset of these disorders are fixed, namely at birth, and their ultimate outcomes may be expected within relatively short time. Length bias may largely be avoided by correction for severity of the disorder, which can be adequately assessed by modern diagnostic procedures. Selection bias is generally hard to rule out, but in these cases it probably plays a minor part. Over-treatment can be avoided by the policy of "watchful waiting", which in these disorders can be applied with little risk for fatal outcomes. In principle bias might be avoided more successfully in a case-control screening evaluation than in a patient follow up study. However, the patient follow up study is for both screening programmes discussed here the more feasible design and can provide more supplementary information. The results of two example studies suggest that both screenings probably yield considerable benefits CONCLUSION: Under a number of specific conditions a patient follow up study is an efficient alternative to more customary designs for screening evaluation. 相似文献
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目的:研究唐古特大黄提取物不同成分的泻下作用。方法:采用炭末推进方法、酚红排空方法进行肠推进实验,观察大黄提取物各成分(15 g·kg-1)对小鼠小肠推进和肠水分吸收、大鼠大肠运动的影响。结果:唐古特大黄提取物不同成分与对照组相比,对小鼠小肠推进和肠水分吸收、大肠推进作用均有显著性差异(P<0.01);与大黄水煎液、醇提液相比,泻下活性存在一些差异。结论:唐古特大黄提取物不同成分均有显著的泻下作用,但与大黄水煎液和醇提液相比有一些差异。 相似文献
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Decellularized dermis in combination with cultivated keratinocytes in a short- and long-term animal experimental investigation 总被引:4,自引:0,他引:4
H Bannasch† GB Stark† F Knam† RE Horch‡ M Föhn† 《Journal of the European Academy of Dermatology and Venereology》2008,22(1):41-49
Decellularized human dermis as a potentially ideal scaffold for dermal substitution in severe burns was examined in a two‐staged animal experiment. In an initial step, an in vitro generated composite graft consisting of human keratinocytes and decellularized dermis (AlloDerm®) was transplanted onto nude mice in a short‐term trial (n = 20, 14 days). Subsequently, a combined one‐step grafting of full thickness wounds with both decellularized dermis (in part preincubated with fibroblasts) and cultivated autologous keratinocytes as a cell suspension in fibrin glue was done in a long‐term porcine animal model (n = 10, 6 months). In both series, macroscopic wound healing was evaluated by planimetry. Histological investigations included morphological as well as immunohistochemical parameters. The short‐term study showed both successful integration of the composite grafts and reduction of wound contraction compared with the control group (epithelial grafts). The long‐term porcine study displayed reduced myofibroblast formation and contraction in the wounds that had been treated with fibroblast‐preincubated dermis. After 4 weeks, a decline of the structural integrity of the dermal matrix could be noticed. The utility of decellularized dermis as template for both dermal reconstitution and keratinocyte delivery vehicle was shown. The closure of full thickness wounds by a single‐step combination of an autologous keratinocyte fibrin sealant suspension and acellular dermis in a pig animal model could be shown. Incorporation of fibroblasts led to reduced wound contraction but could not prevent the loss of dermal integrity. The engineered ‘skin’ remained viable and stable over a period of 6 months. 相似文献