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151.
PURPOSE: To investigate the clinical and histologic response of Novabone-C/M as an osteoproductive alloplastic implant for volume augmentation in the orbit in the treatment of enophthalmos and to compare its outcome alone versus its use in combination with autogenous bone or Medpor granules. METHODS: Novabone-C/M, a bioactive silicone glass material, was implanted in the subperiosteal space of the left orbit of 12 New Zealand White rabbits. The animals were divided into 3 groups, each with 4 animals, based on the material implanted in the orbit: group 1, Novabone alone; group 2, Novabone plus Medpor granules; and group 3, Novabone plus autogenous bone fragments. All rabbits were studied clinically, radiographically, and histologically at 1-, 3-, and 6-month intervals. Animals underwent preoperative and postoperative computed tomography (CT) with 3-dimensional reconstruction, proptosis measurements, and volumetric analysis. Orbit specimens were studied histologically with mineralized bone stain (MIBS) to look for bone formation, reactivity, infection, implant resorption, and migration. RESULTS: There were no signs of significant inflammation or infection. Subcutaneous migration of the implant was seen radiographically but not clinically in groups 1 and 3. Induced proptosis averaged 2.5 mm (at 1 month) and showed regression in all groups over a 6-month period but was not statistically significant. Implant volume was markedly reduced in all groups, averaging 69% in group 1, 37% in group 2, and 59% in group 3 at 6 months. New bone formation and bone remodeling was present in all 3 groups at 3 months and only in group 2 at 6 months. The rate and amount of implant remodeling and bone formation was greatest in the Novabone/Medpor group (group 2). CONCLUSIONS: Bioglass particulate is biocompatible, easy to use in the orbit, and stimulates bone growth. Bioglass is associated with volume loss and migration over 6 months and may not provide adequate volume augmentation in the orbit when used alone for the treatment of enophthalmos. The duration and amount of bone formation may be enhanced when Novabone is used in conjunction with Medpor.  相似文献   
152.
Our objective was to define the possibility of using oral-contrast-enhanced helical CT for the assessment of patients with cholecystolithiasis and of cholecystectomized symptomatic patients. Twenty-seven patients with cholecystolithiasis and 20 with a painful abdominal symptomatology after cholecystectomy (12 laparoscopic and 8 laparotomic) were recruited for this study. Cholangio-CT was performed 12–14 h after oral administration of 6 g of hyopanoic acid. The acquired data were then transferred to a second workstation and 3D reconstruction of the biliary tract was obtained. In all the cases the extrahepatic bile ducts were recognizable. Seven patients had no gallbladder opacification: CT images showed in 3 cases an infundibular stone and in 4 cases sclero-atrophic gallbladder. The intrahepatic bile ducts were visible in 21 of 27 patients with lithiasis and in 14 of 20 cholecystectomized patients. In 5 cholecystectomized patients cholangio-CT demonstrated the presence of residual choledochal or intrahepatic stones. In 3 cholecystectomized patients 3D reconstruction allowed identification of a long and winding stump of the cystic duct. Cholangio-CT is a non-invasive method to evaluate the biliary tract in patients who cannot be subjected to cholangio-MR, or as a preliminary to endoscopic retrograde cholangiopancreatography in cases of doubtful diagnosis after US and cholangio-MR. Electronic Publication  相似文献   
153.
Transient ovarian failure: a complication of uterine artery embolization   总被引:20,自引:0,他引:20  
OBJECTIVE: To report a case of transient ovarian failure shortly after arterial embolization for treatment of uterine fibroids, followed by recovery of ovarian function. DESIGN: Case report. SETTING: A university-based hospital. PATIENT: A 49-year-old woman with menorrhagia and anemia secondary to uterine fibroids and refractory to medical management. The follicle-stimulating hormone (FSH) level on cycle day 3 before the procedure was 8.2 mIU/mL. INTERVENTION(S): Bilateral uterine artery embolization for treatment of menorrhagia. MAIN OUTCOME MEASURE(S): Serum FSH level. RESULT(S): The patient developed amenorrhea and hot flashes 3 months after uterine artery embolization. Her serum FSH level at that time was 140.1 mIU/mL. Four months later, uterine bleeding resumed; her serum FSH level was 2.1 mIU/mL. CONCLUSION(S): Uterine artery embolization may hasten ovarian failure. This procedure should be reserved for women who have completed their child-bearing or are poor candidates for myomectomy. Patients should be counseled appropriately about the risk of possible ovarian failure.  相似文献   
154.
We investigated the function of Xrx1 during Xenopus retinogenesis. Xrx1 overexpression lengthens mitotic activity and ectopically activates the expression of markers of undifferentiated progenitors in the developing retina. We assayed Xrx1 ability to support proliferation with a cell-autonomous mechanism by in vivo lipofection of single retinal progenitors. Xrx1 overexpression increases clonal proliferation while Xrx1 functional inactivation exerts the opposite effect. We also compared the effects of Xrx1 with those of the cyclin-dependent kinase cdk2, a strong mitotic promoter. Despite the similar increase in clonal proliferation displayed by both factors, Xrx1 and cdk2 act differently on retinal cell fate determination. cdk2/cyclinA2 lipofected retinas show a decrease in early-born cell types as ganglion cells and cones and an increase in late-born types such as bipolar neurons. On the contrary, Xrx1 lipofected retinas show no changes in the proportions of the different cell types, thus suggesting a role in supporting multipotency of retinal progenitors.  相似文献   
155.
Information from patients who are unable to continue their visits to a study centre may be of major importance for the interpretation of results in multiple sclerosis (MS) clinical trials. To validate a questionnaire based on the Expanded Disability Status Scale (EDSS), patients in five different European centres were assessed independently by pairs of trained EDSS raters, first by telephone interview and a few days later by standardized neurological examination. Seventy women and 40 men with an average age of 43.7 years (range 19-74 years) were included in the study. Mean EDSS score at the last visit was 4.5 (0-9). EDSS assessment by telephone was highly correlated with the EDSS determined by physical examination (Pearson's correlation coefficient = 0.95). An intraclass correlation coefficient (ICC) of 94.8% was found for the total sample; 77.6% and 86%, respectively, for patients with EDSS < 4.5 (n = 46) and > 4.5 (n = 64). Kappa values for full agreement were 0.48; for variation by +0.5 steps and +1.0 steps, 0.79 and 0.90, respectively. Best agreement could be found in higher EDSS scores, where assessment by telephone interview might be needed most. The telephone questionnaire is a valid tool to assess EDSS score in cases where the patient is unable to continue visiting a study centre or in long-term follow-up of trial participants.  相似文献   
156.
Neuromuscular complications of cancer are common and can affect any component of the peripheral nervous system from peripheral nerve cell body to muscle. Perhaps the most common complication is a length-dependent symmetric axonal polyneuropathy that is often multifactorial in etiology, resulting from metabolic and treatment effects of the primary malignancy. However, neuromuscular disorders may also be the presenting complaint in many conditions, including disorders caused by malignant infiltration of nerve and disorders cause by paraneoplastic syndromes. Although many of the paraneoplastic conditions are poorly responsive to treatment, not all are, and one hopes that prompt diagnosis of the underlying malignancy will lead to improved patient outcome. Recognition of iatrogenic neuromuscular complications is also important to modify treatment protocols when possible and thus decrease the risk of long-term neurologic disability.  相似文献   
157.
Over the past decade, there has been considerable interest in assessing the importance and functional impact of cognitive impairment in multiple sclerosis (MS), its clinico-magnetic resonance imaging correlates, and possible approaches to clinical management. There is preliminary evidence that treatment with both disease-modifying and symptomatic agents may positively influence the cognitive outcome of the patient, but few studies have assessed the efficacy of cognitive rehabilitation programmes using an experimental design. To make further progress in the field of neuropsychological diagnosis, it is essential to validate sensitive, cost-effective and reliable screening instruments that can be used, in clinical settings, to identify patients appropriate for extensive neuropsychological assessment, and finalize tailor-made rehabilitation techniques for MS patients.  相似文献   
158.
Gelatinous marrow transformation is characterized by marrow hypoplasia, fat atrophy, and gelatinous material deposition, and usually develops as a hematologic complication of chronic wasting disorders. Most of the cases associated with severe nutritional deficiency were seen in anorexia nervosa due to a depletion of protein or fat. This report describes a case of gelatinous transformation attributed to a specific restriction of carbohydrates in diet. The hematologic deficiency was eventually recovered after the patient resumed a regular starch-containing diet. This brief report illustrates the potential side effect of the compulsive dietary behavior on the hematologic system.  相似文献   
159.
Patients under pressure support ventilation sometimes encounter patient-ventilator asynchrony in the transition from inspiration to expiration, that is, expiratory asynchrony. This problem is caused by the incompatibility of the fixed level of expiratory trigger sensitivity termination criteria (i.e., flow termination criteria) in the ICU ventilators to various patient conditions. The user-adjustable expiratory trigger sensitivity implemented in some newly released ventilators has been experienced to be difficult to use and unable to adapt ever-changing patient conditions without user intervention, although it provides more flexibility. This article elucidates the rationale for automatic control of the expiratory trigger sensitivity and evaluates the automation system with a bench setup. The evaluation data suggest that good expiratory synchronies can be achieved through automatic adjustments of expiratory trigger sensitivity.  相似文献   
160.
We describe the case of a 53-year-old woman presenting papulous and papulovesicular lesions that were highly pruritic, localized mostly in the achromic areas of vitiligo and symmetrically distributed on the elbows, the buttocks, the shoulders and the neck. The histopathological examination performed on the elbow's lesional skin showed the presence of neutrophils and fibrin microabscesses at the tips of dermal papillae, with a few eosinophils, and small separations between the dermis and epidermis just over the infiltrate. The overlying epidermis was uninjured. The performed tests detected IgA anti-endomysium, anti-thyrogloblin, anti-smooth muscle and anti-microsomal fraction autoantibodies; DIF showed the presence of IgA granular deposits at the dermo-epidermal junction, prevalently at the tips of dermal papillae. This is the tenth case reported of an association between dermatitis herpetiformis and vitiligo. Although the two disorders both have immunological pathogeneses, we think that the topographic coexistence of both disorders is coincidental.  相似文献   
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