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81.
Fetal iodine deficiency disorder (FIDD) is the principal form of endemic cretinism, and the most common cause of preventable mental deficiency in the world. However not everyone at risk develops FIDD and familial aggregation is common. This suggests that genetic factors may also be involved. The Apolipoprotein E (APOE) gene encodes for a lipoprotein that possesses a thyroid hormone binding domain, and APOE genotype may affect the efficiency with which thyroid hormone influences neuronal cell growth during the first and second trimesters of fetal development. We have compared ApoE genotypes in 91 FIDD cases with 154 local control subjects, recruited from three iodine deficiency areas in central China. We have also genotyped 42 FIDD family cases and 158 normal individuals from the families of local controls, and 375 population controls from Shanghai. APOE epsilon4 genotypes were significantly enriched in FIDD probands from each of the three iodine deficiency areas; the epsilon4 allele frequency was 16% vs 6% in controls. The same effect was also observed when we compared FIDD family cases with controls and control families. Our data suggest that in iodine-deficient areas, the APOE epsilon4 allele is a genetic risk factor for FIDD. The phenomenon may affect population selection and contribute to the low frequency of the epsilon4 allele in Chinese compared to Caucasian populations.  相似文献   
82.
83.
The effects of speech output and orthographic feedback on spelling performance were evaluated in this preliminary study. A nonspeaking student with autism was taught to spell words under three feedback conditions using a voice output communication aid. In the auditory-visual condition, the participant received speech output and orthographic feedback. In the visual condition, the participant received only the orthographic feedback. In the auditory condition, the student received only speech output. An adapted alternating treatments design was used to evaluate the effects of the three feedback conditions. Although the participant reached criterion and maintained performance in each of the conditions, the provision of speech output alone and in combination with orthographic feedback resulted in more efficient spelling than the provision of orthographic feedback alone. Although replications with other subjects are necessary, findings suggest that speech output contributes to efficient spelling.  相似文献   
84.
A randomized comparison of aztreonam (2 g intravenously every eight hours) versus gentamicin (1.5 mg/kg intravenously every eight hours), each with clindamycin (600 mg intravenously every six hours), was performed in 119 patients with endometritis after cesarean section. Patients in both groups had similar risk factors. Genital cultures revealed an average of 3.0 isolates per specimen. Eighty-five aerobic gram-negative rods were isolated from 57 (48%) patients. All were susceptible to both aztreonam and gentamicin. Of 133 anaerobic isolates, 131 (98%) were susceptible to clindamycin. The failures in the aztreonam group were associated with a wound abscess and with an enterococcal bacteremia. Of the six failures in the gentamicin group, two were associated with persistent isolation of enteric bacilli. In the other four failures, no explanation was evident. Side effects occurred in four patients, (three diarrhea, one allergic reaction). All were self-limited and appeared to be due to clindamycin. No patient showed nephrotoxicity. When used in combination with clindamycin, aztreonam gave clinical results similar to gentamicin.  相似文献   
85.
Polyethylene glycol 400, a commonly used plasticizer in many cosmetic aerosol hair sprays, was tested to determine its effect on perfusion pressure, perfusion vascular flow rate, and tidal volume in the perfused isolated guinea pig lung. Negative pressure was maintained within the chamber housing the intact lungs, and initial perfusion of the pulmonary vasculature was accomplished via the right side of the heart in situ after guinea pigs were sacrificed by decapitation. Polyethylene glycol 400 was injected into the pulmonary arterial system in doses of 0.01-30 microgram/ml after pretreatment with isoproterenol (1 microgram/ml). Isoproterenol was then readministered, followed by nebulized doses of the cosmetic chemical into the trachea at 0.3, 3, and 30% concentrations. Nebulized polyethylene glycol 400 was also administered in 50, 70, and 90% concentrations. Polyethylene glycol 400 significantly increased perfusion pressure and flow rate after injection into the pulmonary arterial system of the isolated lung. In addition, nebulized administration in concentrations of 0.3-30% significantly increased the perfusion flow rate; following the 50-90% nebulized doses, a significant increase in both perfusion pressure and flow rate was observed. Tidal volume decreased, regardless of the route of administration, as increasing doses of the cosmetic constituent were delivered to the isolated lung.  相似文献   
86.
Recurrent instability in patients over forty years of age is felt to occur primarily as a result of an associated rotator cuff tear. This is often referred to as the "posterior mechanism." We reviewed our patients over the age of forty who underwent an anterior shoulder repair to identify the incidence of capsulolabral detachments and the role of an "anterior mechanism" in this patient population. A retrospective review of all patients from 1985 to 2000 was performed to identify patients who had surgery for recurrent instability that began after forty years of age. Of the 265 patients records reviewed, 11 patients were identified who fulfilled the inclusion criteria. Of the 11 patients identified, 9 patients underwent anterior capsulolabral reconstruction for recurrent instability; the remaining two patients underwent repair of large rotator cuff tears. All 9 patients had a capsulolabral detachment, 4 had a rotator interval defect, 2 had anterior and inferior capsular redundancy, 1 had a small rotator cuff tear and 1 had an anterior capsular avulsion from the humeral head. At minimum follow-up of 32 months none of the patients reported episodes of instability. The reported incidence of rotator cuff tears in patients over the age of forty following an initial traumatic anterior glenohumeral dislocation ranges from 35% to 100%. When recurrent instability occurs, it is postulated to occur via a "posterior mechanism" (i.e., secondary to a significant full-thickness rotator cuff tear). However, all of our patients had an anterior capsulolabral detachment as the "common lesion" associated with recurrent instability. Although small, this series emphasizes the role of the "anterior mechanism" in patients who develop recurrent instability after the age of forty. A high rate of success was achieved by addressing the pathoanatomic changes identified.  相似文献   
87.
OBJECTIVE: This study evaluates the efficacy of bovine peritoneum/fascia as an arterial substitute. METHODS AND OUTCOME MEASURES: Twelve dogs underwent bilateral femoral artery patch angioplasty with a glutaraldehyde-fixed bovine peritoneal/fascial patch (PFA patch) on one side and polyester patch on the contralateral side. Arteriograms were performed just before vessel harvest at 1 and 6 months, and vessels were evaluated for aneurysms and inflammation. Histologic analysis included intima area, media thickness, and lumen area. Immunofluorescence for CD 34 and Factor VIII was done to evaluate endothelialization and alpha-actin for smooth muscle cell growth. Mechanical strength testing was evaluated in separate PFA patches and compared independently to a commercially available bovine pericardial patch and polyester patch. RESULTS: All vessels examined at both 1 and 6 months were patent with no arteriographic evidence of stenosis. There was no evidence of aneurysm formation in any vessel and no difference between groups in inflammatory reaction. One polyester patch at 1 month developed an infection. Microscopic evaluation of experimental vessels revealed no difference between groups in intima area at 1 month (2.1 +/- 1.2 vs 2.2 +/- 1.2 mm 2 ; P = .5) and at 6 months (1.81 +/- 1.2 vs 1.9 +/- 1.2 mm 2 ; P = .5). There was no difference in media thickness, but the PFA patch group had a greater lumen area at 1 month (8.8 +/- 2.9 vs 9.8 +/- 3.0 mm 2 ; P = .02) and 6 months (10.5 +/- 4.2 vs 11.7 +/- 5.6 mm 2 ; P = .02). Immunofluorescence for CD34 and Factor VIII demonstrated complete re-endothelialization of all patches. The polyester patch had a chronic inflammatory response, but not the PFA patch. Mechanical strength testing demonstrated that compared to pericardium, the PFA patch had superior ( P < .05) failure tension, stiffness, and suture pull-out strength, whereas extensibility, fatigue tension, relax slope, and creep tests were not different. Polyester demonstrated superior suture pull-out, stiffness, relax slope, and failure strain ( P < .05), but it was not different in failure tension and extensibility than the PFA patch. However, the PFA patch had significantly less creep (0.25 +/- 0.25 vs 4.92 +/- 0.84; P < .01). CONCLUSIONS: The PFA patch has similar clot-resistant properties to polyester and is superior to the pericardial patch in mechanical strength. It is a promising endothelial alternative for not only arterial patches but other vascular products. CLINICAL RELEVANCE: The search for an artificial, thromboresistant, and intimal hyperplasia resistant interface between blood and native blood vessels still continues. This study demonstrates the feasibility and proof of concept of the peritoneum's clot-resistant properties. When adding the underlying fascia, it serves as an ideal arterial patch. Other studies are underway evaluating its feasibility as a bypass graft and a "drug coated"-like stent lining.  相似文献   
88.
Prosthetic vascular graft infection is an uncommon yet serious condition. Traditional management has included debridement, excision of the infected graft, and revascularization as needed. We report on two cases in which limb viability was maintained by using endovascular native vessel recanalization after excision of infected prosthetic grafts. This approach was successful in maintaining adequate limb perfusion in both cases. Endovascular native vessel recanalization should be considered as an option to maintain limb viability after excision of infected prosthetic vascular grafts, especially when autogenous conduit is lacking or limitation of the extent of surgery is desirable.  相似文献   
89.
BACKGROUND: Fenestrated endovascular aneurysm repair uses the visceral aortic segment, in the setting of a suboptimal proximal neck, for sealing and fixation. This technique requires the placement of visceral stents and might be hampered by the deleterious effects of such interventions. This study was performed to define outcomes related to renal events. MATERIALS AND METHODS: Consecutive clinical records and radiographic studies of patients treated primarily with an endovascular approach with a fenestrated endograft were reviewed. The population was divided into groups with and without baseline renal dysfunction based on the National Kidney Foundation definition of chronic kidney disease. Morphologic measurements and the detection of postoperative renal events such as renal artery stenosis or occlusion, need for dialysis, deterioration of renal function by using estimated glomerular filtration rate (GFR), and secondary interventions related to the renal arteries were assessed. Preoperative and postprocedural factors predictive for the development of renal dysfunction were assessed by using a Fisher exact test, t test, and logistic regression. RESULTS: A total of 72 patients were treated between 2001 and 2004 with a mean age, aneurysm size, and follow-up of 75 years, 6.2 cm, and 6 months (range, 1 to 24 months), respectively. No ruptures and five deaths (two procedure-related) were observed. There were 23 patients with baseline renal insufficiency and 49 patients without insufficiency. Twenty-four patients had deterioration in GFR >30% during the follow-up period, and 17 patients experienced 19 renal-related events (more common in patients with baseline insufficiency, 39% vs 16.3%; P = .04; relative risk, 2.4). Four patients required dialysis (two permanent), and all had preoperative renal dysfunction ( P = .002); similarly, death was also more common in this group (17.4% vs 2%; P = .02; relative risk, 8.52). Renal events in most patients occurred within the first postoperative month (59%). However, mean GFR stabilized after 6 months. CONCLUSION: Aneurysm repair with fenestrated endovascular grafts is associated with a significant risk for adverse renal events (16% in those without renal dysfunction, although none developed a creatinine >2 mg/dL, and 39% for patients with preoperative renal dysfunction). These patients must be meticulously followed, particularly within the first month after such a procedure. When renal artery restenosis is suspected or diagnosed, aggressive approach might be warranted to limit the extent of late renal dysfunction.  相似文献   
90.
PURPOSE: This prospective study was designed to assess the technical success and outcome after patients with thoracic aortic pathology at high risk for conventional therapy were treated with the Zenith TX1 and TX2 endovascular graft. METHODS: Between 2001 and 2004, patients at high risk for conventional surgical therapy presenting with chronic aortic dissections, thoracic aneurysms, or aortobronchial or aortoesophageal fistulas were treated with a single- or multiple-piece endovascular grafts. Surgical modification of proximal or distal fixation sites was performed when necessary to establish adequate regions for device landing zones. Follow-up studies included radiographic evaluation before discharge and at 1, 6, 12, and 24 months. Aortic morphologic characteristics were determined by using three-dimensional imaging studies and centerline of flow measurements. Statistical analyses were performed with Kaplan Meier analysis to assess survival, factors predictive of poor outcome, and morphologic changes, including sac shrinkage. RESULTS: A total of 100 patients (42% women) were treated, including 81 aneurysms, 15 aortic dissections (with aneurysms), 2 patients with fistulous connections (1 aortobronchial and 1 aortoesophageal), 1 subclavian artery aneurysm, and 1 aortic rupture. Mean follow-up and aneurysm size were 14 months and 62 mm, respectively. Most patients (55%) had undergone prior aortic aneurysm repair. Surgical modifications were required to create adequate implantation sites in 29% patients, including 14 elephant trunk/arch reconstructions, 18 carotid-subclavian bypasses, and 4 visceral vessel bypasses. Iliac conduits were required in 19 patients. Overall mortality was 17%, and aneurysm-related mortality was 14% at 1 year. Sac regression (>5 mm maximum diameter decrease) was observed in 52% and 56% at 12 and 24 months. Growth was noted in one patient (1.6%) at 12 months. Endoleaks were detected in eight patients (8.5%) at 30 days and three patients (6%) at 12 months. Secondary interventions were required in 15 patients. Migration (>10 mm) of the proximal or distal stent was noted in three patients (6%) (two proximal and one distal), none of which required treatment or resulted in an adverse event. CONCLUSIONS: Acceptable intermediate-term outcomes have been achieved in the treatment of high-risk patients in the setting of both favorable and challenging anatomic situations with these devices. The complexity of the patient population, in contrast to endovascular infrarenal repair, attests to the differences in the pathophysiology aortic disease in the anatomic beds.  相似文献   
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