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101.
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We compared two methods of 3D digital subtraction angiography (DSA)--propeller and standard rotation--for the assessment of aneurysmal morphology and its relation to neighboring vessels. Aneurysms were correctly visualized and localized with both techniques. 3D DSA with propeller rotation technique seems to be effective and allows us to reduce the amount of contrast material related to a shortened acquisition time. Technical progress including propeller rotation allows a larger range of rotation and faster rotational speeds.  相似文献   
103.
Cerebral venous thrombosis (CVT) can be difficult to diagnose because of its wide spectrum of clinical manifestations. Its diagnosis may be further complicated when patients initially present with acute subarachnoid hemorrhage (SAH). We report on four patients with SAH revealing a CVT and discuss the role of imaging for diagnostic and pretherapeutic workup. In three women and one man presenting with severe headaches, images initially suggested SAH with no associated parenchymal bleeding. In all patients, SAH involved the sulci of the convexity and spared the basal cisterns. Digital subtracted angiography showed occlusion of intracranial venous sinuses but did not reveal any other cause of SAH. All patients improved with anticoagulant therapy. Risk factors for CVT and SAH, namely, head trauma and oral contraception, were identified in two patients. These cases highlight the fact SAH may reveal a CVT, which should be considered in the diagnostic workup of SAH, especially when the basal cisterns are not involved.  相似文献   
104.
A new, coated bioactive coil has been developed to improve the long-term results of endovascular treatment of intracranial aneurysms. The purpose of this preliminary study was to assess the feasibility and safety of selective embolization of intracranial aneurysms with Matrix coils in 20 consecutive patients.  相似文献   
105.
Vitamin D metabolites alphacalcidol and calcitriol (D-hormones) have been investigated for two decades, but few and conflicting results are available from high-quality randomized controlled trials. Our objectives were to provide an evidence-based update quantitatively summarizing their efficacy on bone mineral density (BMD) and fracture rate. We performed a systematic research of any randomized controlled trial containing relevant data, peer review, data extraction and quality scoring blinded for authors and data sources, and comprehensive meta-analyses of the relevant data. Inclusion criteria were: randomized controlled study, calcitriol or alphacalcidol, BMD or fractures in healthy/osteopenic/osteoporotic patients exposed or not to corticosteroids (CS). Analyses were performed in a conservative fashion using professional dedicated softwares and stratified by outcome, target patients, study quality, and control-group type. Results were expressed as effect size (ES) for bone loss or relative risk (RR) for fracture while allocated to D-hormones vs control. Publication bias and robustness were investigated. Of the trials that were retrieved and subsequently reviewed, 17 papers fitted the inclusion criteria and were assessed. Quality scores ranged from 20 to 100%, the mean (standard deviation) being 72 (22)%. Calcitriol and alphacalcidol were found to have the same efficacy on all outcomes at p>0.13. We globally assessed D-hormones effects in preventing bone loss in patients not exposed to CS, and found positive effect: ES=0.39 (p<0.001). For lumbar spine, this particular effect was 0.43 (p<0.001). D-hormones significantly reduced the overall fracture rates: RR=0.52 (0.46; 0.59) and both vertebral and non-vertebral fractures: RR=0.53 (0.47; 0.60) and RR=0.34 (0.16; 0.71), respectively. No statistical difference in response was observed between results from studies on healthy and osteoporotic patients or depending on the fact that controls were allowed to calcium supplementation. Treatment with D-hormones was evaluated for maintaining spinal bone mass in five trials of patients with CS-induced osteoporosis, and provided ES=0.43 at p<0.001. Only two studies specifically addressed the effects of calcitriol on spinal fracture rate. None of them provided significant results, and the global RR did not reach the significance level as well: RR=0.33 (0.07; 1.51). Our data demonstrated efficacy for DH on bone loss and fracture prevention in patients not exposed to CS and on bone loss in patients exposed to CS, in the light of the most reliable scientific evidence. Their efficacy in reducing the number of fractures in patients exposed to CS remains to be determined.  相似文献   
106.
The adrenal gland can frequently be the site of metastatic deposits, including malignant melanocytic tumors; however, primary melanoma of the adrenal gland is exceptional. We reviewed 18 cases reported in the English literature to date, and here add another case which occurred in a 78-year-old man. The patient underwent right suprarenalectomy and the pathology report showed a malignant melanoma of the adrenal gland. Immunohistochemical staining revealed a positive antibody-specific cytoplasmic reactivity to S-100 and HMB-45 proteins with a negative reaction for cytokeratin (AE1, AE3), synaptophysin, chromogranin and neuron-specific enolase. There are diagnostic criteria for accepting an adrenal melanoma as primary; however, an autopsy is the final step to confirm this infrequent pathology.  相似文献   
107.
BACKGROUND: Recent innovations in the pharmaceutical drug discovery environment have generated new chemical entities with the potential to become disease modifying drugs for osteoarthritis (DMOAD's). Regulatory agencies acknowledge that such compounds may be granted a DMOAD indication, providing they demonstrate that they can slow down disease progression; progression would be calibrated by a surrogate for structural change, by measuring joint space narrowing (JSN) on plain X-rays with the caveat that this delayed JSN translate into a clinical benefit for the patient. Recently, new technology has been developed to detect a structural change of the OA joint earlier than conventional X-rays. OBJECTIVE: The Group for the Respect of Ethics and Excellence in Science (GREES) organized a working party to assess whether these new technologies may be used as surrogates to plain x-rays for assessment of DMOADs. METHODS: GREES includes academic scientists, members of regulatory authorities and representatives from the pharmaceutical industry. After an extensive search of the international literature, from 1980 to 2002, two experts meetings were organized to prepare a resource document for regulatory authorities. This document includes recommendations for a possible update of guidelines for the registration of new chemical entities in osteoarthritis. RESULTS: Magnetic resonance imaging (MRI) is now used to measure parameters of cartilage morphology and integrity in OA patients. While some data are encouraging, correlation between short-term changes in cartilage structure observed with MRI and long-term radiographic or clinical changes are needed. Hence, the GREES suggests that MRI maybe used as an outcome in phase II studies, but that further data is needed before accepting MRI as a primary end-point in phase III clinical trials. Biochemical markers of bone and cartilage remodelling are being tested to predict OA and measure disease progression. Recently published data are promising but validation as surrogate end-points for OA disease progression requires additional study. The GREES suggests that biochemical markers remain limited to 'proof of concept' studies or as secondary end-points in phase II and III clinical trials. However, the GREES emphasizes the importance of acquiring additional information on biochemical markers in order to help better understand the mode of action of drugs to be used in OA. Regulatory agencies consider that evidence of improvement in clinical outcomes is critical for approval of DMOAD. Time to total joint replacement surgery is probably the most relevant clinical end-point for the evaluation of efficacy of a DMOAD. However, at this time, time to surgery can not be used in clinical trials because of bias by non disease-related factors like patient willingness for surgery or economic factors. At this stage, it appears that DMOAD should demonstrate a significant difference compared to placebo. Benefit should be measured by 3 co-primary end-points: JSN, pain and function. Secondary end-points should include the percentage of patients who are 'responder' (or 'failure'). The definition of a 'failure' patient would be someone with progression of JSN>0.5mm over a period of 2-3 years or who has a significant worsening in pain and/or function, based on validated cut-off values. The definition of the clinically relevant cut-off points for pain and function must be based on data evaluating the natural history of the disease (epidemiological cohorts or placebo groups from long-term studies). These cut-offs points should reflect a high propensity, for an individual patient, to later require joint replacement. CONCLUSION: GREES has outlined a set of guidelines for the development of a DMOAD for OA. Although these guidelines are subject to change as new information becomes available, the information above is based on the present knowledge in the field with the addition of expert opinion.  相似文献   
108.
OK-432 therapy for cervical lymphangioma   总被引:5,自引:0,他引:5  
OBJECTIVE: To describe our experience with sclerosing treatment of lymphangiomas in the head and neck region by intralesional injections of OK-432. STUDY DESIGN: Case series. METHODS: Patients with the diagnosis of a macrocystic-type cervical lymphangioma were treated by one to three intralesional injections of OK-432 (0.01 mg of OK-432/1 mL of lymphangioma fluid, up to a maximum of 0.2 mg in the first injection and 0.3 mg in the second or third injections). All injections were performed under ultrasound guidance. Children were injected under sedation. RESULTS: Eleven patients were treated with injections of OK-432: 7 children and 4 adults. They were followed up for a period of 5 to 68 (mean 30) months. Eight (73%) patients had complete or subcomplete resolution of the lymphangioma after one or two injections. In three (27%) cases, no response was obtained (2 cases) or the lymphangioma recurred (1 case) after two to three injections. In two cases, surgical excision was performed. There was no evidence of fibrosis around the cysts. There were no complications to OK-432 injections. CONCLUSION: Intralesional injection of OK-432 is an effective treatment modality for macrocystic-type lymphangiomas in the head and neck region. It has no complications, and surgical excision in case of failure is not compromised by fibrosis. Sclerosing of macrocystic-type lymphangiomas with OK-432 should therefore be considered before surgical excision.  相似文献   
109.
110.
Objective To evaluate the impact of continuous subglottic suctioning and semi-recumbent body position on bacterial colonisation of the lower respiratory tract.Design A randomised controlled trial.Setting The ten-bed medical ICU of a French university hospital.Patients Critically ill patients expected to require mechanical ventilation for more than 5 days.Interventions Patients were randomly assigned to receive either continuous suctioning of subglottic secretions and semi-recumbent body position or to receive standard care and supine position.Measurements and results Oropharyngeal and tracheal secretions were sampled daily and quantitatively cultured. All included patients were followed up from day 1 (intubation) to day 10, extubation or death. Ninety-seven samples of oropharynx and trachea were analysed (40 for the suctioning group and 57 for the control group). The median bacterial counts in trachea were 6.6 Log10 CFU/ml (interquartile range, IQR, 4.4–8.3) in patients who received continuous suctioning and 5.1 Log10 CFU/ml (IQR 3.6–5.5) in control patients. Most of the patients were colonised in the trachea after 1 day of mechanical ventilation (75% in the suctioning group, 80% in the control group). No significant difference was found in the daily bacterial counts in the oropharynx and in the trachea between the two groups of patients.Conclusion Tracheal colonisation in long-term mechanically ventilated ICU patients was not modified by the use of continuous subglottic suctioning and semi-recumbent body position.  相似文献   
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