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51.
In this pilot study, we show that plasma phenylalanine concentration can be predicted from urine concentration if the age of the patient is taken into consideration. This observation could open the way to a new monitoring of phenylketonuric patients in which painful frequent blood sampling, mandatory to adapt the low phenylalanine diet, could be mostly replaced by urinalysis. Compliance to treatment would be improved and hence also the ultimate mental development. Since this study was based on a small number of patients, validation of the model in a large multicentric survey is needed before it can be recommended.  相似文献   
52.
Fate of branch arteries after intracranial stenting   总被引:14,自引:0,他引:14  
Lopes DK  Ringer AJ  Boulos AS  Qureshi AI  Lieber BB  Guterman LR  Hopkins LN 《Neurosurgery》2003,52(6):1275-8; discussion 1278-9
OBJECTIVE: One concern with respect to stent procedures performed to treat patients with intracranial lesions is the fate of normal major arterial branches after stents are placed across them. Because most of these lesions occur at vessel bifurcations or at branch points, a normal major branch often arises near the lesion and may be difficult to avoid during stent positioning. The aim of this article is to describe the angiographic outcome of intracranial major branch arteries crossed by a stent in the intracranial circulation. METHODS: We examined the immediate postprocedural cerebral angiograms of the 40 patients who underwent intracranial stenting at the University at Buffalo, Buffalo, NY, between June 1998 and April 2000. In each of 10 patients, the stent was placed across a normal major branch artery. Stents were used to treat aneurysms in seven patients and intracranial stenosis in three patients. The latest cerebral angiogram available was reviewed, and the patency of the major branch arteries was evaluated. RESULTS: The angiographic follow-up period ranged from 4 days to 35 months (mean follow-up, 10 mo). Each of the 10 major branch arteries was patent. No infarcts were associated with the territory of the major branch arteries crossed by the stents, and no patient experienced a related episode of clinical ischemia. Four patients died as a result of causes unrelated to the stenting procedure. The histology of a middle cerebral artery stent that was placed across a lenticulostriate perforator is presented. CONCLUSION: The flexible, low-profile stents used in this study had no angiographically or clinically apparent effect on the major intracranial branches across which they were placed.  相似文献   
53.
Infrainguinal angioplasty and stenting is becoming a more commonly performed procedure. Its durability remains a matter of debate, however. Aneurysmal degeneration following angioplasty and stenting is a complication not previously described in the literature with regard to the superficial femoral artery. We present a case in which two aneurysms of the superficial femoral artery developed following angioplasty and multiple-stent placements in a patient who had previously undergone a failed femoral-to-below-the-knee popliteal artery PTFE bypass graft. The patient presented to our institution with an occluded, infected bypass graft. He was treated with graft and femoral artery/stent excision and vein bypass grafting. A brief review of infectious complications after stent placement is included.  相似文献   
54.
Recent reports have established the feasibility and safety of percutaneous transluminal angioplasty and stent placement in the treatment of innominate artery occlusive disease. Although the long-term durability of these endovascular approaches has not been clearly established, they are particularly attractive in patients who are not considered good candidates for surgical reconstruction. The authors present a case involving a morbidly obese Hispanic woman who had undergone previous coronary artery bypass and complained of right visual symptoms, dizziness, and right upper extremity claudication. Because of her unusual bovine anatomy and the desire to avoid reoperating in her chest, a unique approach with a left subclavian-to-carotid bypass and innominate artery angioplasty and stenting was used.  相似文献   
55.
Background Fetal tachyarrhythmias are usually of supraventricular origin. To investigate whether specific electrophysiologic properties of the fetal heart contribute to this preponderance by either favoring supraventricular tachycardias or by rendering ventricular tachycardias unlikely, we measured fetal electrophysiologic parameters in utero using transuterine fetal transesophageal electrocardiograms in fetal sheep. Since overdrive pacing may help to establish the mechanism of an arrhythmia and may be used to treat fetal tachycardias, different modes of transesophageal pacing in utero were also assessed. Methods and results Decapolar electrophysiology catheters were fetoscopically inserted into the esophagus of 9 fetal sheep (pregnancy duration 94 – 105 days, term = 145 days). Electrocardiograms were recorded simultaneously from all adjacent bipoles and from two pacing wires sutured onto the fetal shoulders. Pacing was attempted either via two adjacent electrodes of the intraesophageal catheter or via the most distal and most proximal electrode. Fetal cycle length, PQ, and QT intervals were close to (approx. 75 %), but fetal QRS duration was < 20 % of maternal values, thus shifting the relation between activation and repolarization towards longer excitation wave lengths. Fetal QT dispersion was small (≤ 10 ms). Atrial pacing was achieved in all fetuses using distant electrodes, and with lower thresholds when compared to closely spaced bipolar electrodes (p < 0.05). Conclusions (I) An altered relation between ventricular activation and repolarization and a low dispersion of ventricular repolarization may protect the fetal heart against ventricular reentrant tachycardias. (II) Relatively normal fetal AV nodal conduction delay already provides one of the prerequisites for supraventricular reentrant tachycardias involving the AV node at this stage of fetal development. (III) High-rate esophageal pacing of the fetal atria is best achieved using widely spaced bipolar pacing electrodes. Received: 26 July 2000, Returned for 1. revision: 16 August 2000, 1. Revision received: 28 November 2000, Returned for 2. revision: 18 December 2000, 2. Revision received: 23 January 2001, Accepted: 24 January 2001  相似文献   
56.
Gastroduodenoscopy and retrograde cholangiopancreatography has been performed on 25 occasions in 20 children aged between 7 and 16. Radiographs of the clinically relevant duct or ducts were achieved in 96% of attempts, with no complications. The diagnostic information proved useful clinically; in particular it provided a precise map if biliary or pancreatic surgery was being contemplated. Several unexpected congenital duct anomalies were found. This and other recent reports, particularly from Germany, indicate that endoscopic retrograde cholangiopancreatography deserves greater application in children, and can also be used in babies.  相似文献   
57.
The imaging of small abdominal tumours with indium 111 labelled monoclonal antibodies (MAbs) is often obscured by the uptake of activity into the hepto cytes of normal liver tissue. A model has therefore been developed to analyse reagents which may inhibit the he patocyte uptake of111In-MAb whilst preserving tumour uptake. Primary rat hepatocyte cultures and an epithelial membrane antigen (EMA) expressing tumour cell line (MCF7), recognised by the EMA-specific MAb ICR2, were obtained in tissue culture. Monolayers of both cells were incubated with the111In-MAb with or without the additional reagents and the cell uptake then measured and expressed per milligram of cell protein using a Lowry protein assay. No preferential reduction in hepatocyte uptake was noted by incubating cells with either saturated or unsaturated transferrin. The chelating agent, diethylene triamine penta-acetic acid (DTPA), however, significantly reduced the uptake of activity in hepatocytes but not the tumour cell line (TP<0.05). An optimum concentration and time period for incubating DTPA with labelled MAb was established. The mean hepatocyte uptake was reduced by 80% with a 1 h incubation with 1 mM DTPA. These results suggest that DTPA may have a role in reducing the liver uptake of radioactivity in patient studies using111In-MAb.This work was presented at the Society of Nuclear Medicine annual meeting, St. Louis, USA, July 1989  相似文献   
58.
Tropheryma whipplei, the agent of Whipple's disease, grows fastidiously only in cell cultures without plaque production, and only three strains have been passaged. The formation of bacterial clumps in the supernatant precludes enumeration of viable bacteria and MIC determination. We evaluated the bacteriostatic effects of fluoroquinolones against two T. whipplei isolates by measuring the inhibition of the DNA copy number increase by real-time quantitative PCR. The analysis of the T. whipplei genome database allowed the identification not only of the gyrA gene but also the parC gene encoding the alpha subunit of the natural fluoroquinolone targets DNA gyrase (GyrA) and topoisomerase IV (ParC), respectively. The parC gene was detected in actinobacteria for the first time. High ciprofloxacin MICs (4 and 8 micro g/ml) were correlated with the presence in T. whipplei GyrA and ParC sequences with an alanine residue at positions 83 and 80 (Escherichia coli numbering), respectively. Alanines at these positions have previously been associated with increased fluoroquinolone resistance in E. coli and mycobacteria. However, the MIC of levofloxacin was low (0.25 micro g/ml). The same T. whipplei GyrA and ParC sequences were found in two other cultured strains and in nine uncultured tissue samples from Whipple's disease patients, allowing one to speculate that T. whipplei is naturally relatively resistant to fluoroquinolones.  相似文献   
59.
Two cases of laryngeal carcinoma are presented which, upon initial evaluation, were noted to have asymptomatic hypercalcemia with no evidence of bone metastases. Exploration of the parathyroid glands at the time of definitive surgery revealed parathyroid pathology in both cases. Calcium levels returned to normal postoperatively in both cases. We conclude that in patients with head and neck cancer with hypercalcemia and no evidence of bone metastases, parathyroid pathology should be considered. Exploration of the parathyroid glands at the time of definitive surgery or as a separate procedure may prove rewarding.  相似文献   
60.
Boulos P  Dougados M  Macleod SM  Hunsche E 《Drugs》2005,65(15):2111-2127
The purpose of this study was to review the evidence regarding the efficacy and safety of pharmacological therapies currently available for the treatment of ankylosing spondylitis (AS).A literature search using MEDLINE from 1966 through to April 2005 and a hand search of abstracts from the American College of Rheumatology (ACR) meetings for 2001 through to 2004 were performed. References of articles retrieved were also searched.The MEDLINE search yielded 570 citations and 157 abstracts from ACR were identified. Eighty-four studies were randomised controlled trials (RCTs); 53 fulfilled the inclusion criteria (pharmacological treatment of AS and RCT) and were included in this review. Statistical pooling of data was not performed because of the disparate outcome measures used. Eight RCTs found nonselective NSAIDs and two RCTs found cyclo-oxygenase (COX)-2-selective NSAIDs to be superior to placebo for relief of pain and improvement in physical function. Twenty-nine RCTs showed comparable efficacy and safety between nonselective NSAIDs. One RCT showed no difference between methylprednisolone 1g and 375 mg. Seven RCTs assessing the efficacy of sulfasalazine (sulphasalazine) and two RCTs of methotrexate provided contradictory evidence as to their benefit for treatment of AS. One RCT showed intravenous pamidronate 60 mg to be more effective than 10mg intravenously for the treatment of axial pain. All six RCTs of anti-tumour necrosis factor (TNF)-alpha agents demonstrated superiority to placebo for the treatment of axial and peripheral symptoms.Nonselective as well as COX-2-selective NSAIDs can be used for pain control in patients with AS. Other proven treatment options include sulfasalazine for the treatment of peripheral joint symptoms, while limited evidence supports the use of pamidronate or methotrexate, which require further studies. Anti-TNFalpha agents have been found very effective for the treatment of both peripheral and axial symptoms in patients with AS, but their use is limited by cost and uncertainty over long-term efficacy and safety.  相似文献   
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