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51.
Autoimmune pancreatitis: imaging features   总被引:24,自引:0,他引:24  
PURPOSE: To retrospectively determine imaging findings in patients with autoimmune pancreatitis. MATERIALS AND METHODS: Twenty-nine patients (25 male and four female; mean age, 56 years; range, 15-82 years) with histopathologic diagnosis of autoimmune pancreatitis were examined. Data were reviewed by two radiologists in consensus. Imaging findings for review included those from helical computed tomography (CT), 25 patients; magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP), four patients; endoscopic ultrasonography (US), 21 patients; endoscopic retrograde cholangiopancreatography (ERCP), 19 patients; and percutaneous transhepatic cholangiography, one patient. Images were analyzed for appearances of pancreas, biliary and pancreatic ducts, and other findings, such as peripancreatic inflammation, encasement of vessels, mass effect, pancreatic calcification, peripancreatic nodes, and peripancreatic fluid collection. Follow-up images were available in nine patients. Serologic markers such as serum immunoglobulin G (IgG) and antinuclear antibody levels were available in 12 patients. RESULTS: CT showed diffuse (n = 14) and focal (n = 7) enlargement of pancreas. Seven patients had minimal peripancreatic stranding, with lack of vascular encasement, calcification, or peripancreatic fluid collection. Nine patients had enlarged peripancreatic lymph nodes. MR imaging showed focal (n = 2) and diffuse (n = 2) enlargement with rimlike enhancement in one. MRCP revealed pancreatic duct strictures in two and sclerosing cholangitis-like appearance in one. Endoscopic US showed diffuse enlargement of pancreas with altered echotexture in 13 patients and focal mass in the head in six. ERCP showed stricture of distal common bile duct in 12 patients, irregular narrowing of intrahepatic ducts in six, diffuse irregular narrowing of pancreatic duct in nine, and focal stricture of proximal pancreatic duct in six. Serologic markers showed increased IgG and antinuclear antibody levels in seven of 12 patients. At follow-up, CT abnormalities and common bile duct strictures resolved after steroid therapy in three patients. CONCLUSION: Features that suggest autoimmune pancreatitis include focal or diffuse pancreatic enlargement, with minimal peripancreatic inflammation and absence of vascular encasement or calcification at CT and endoscopic US, and diffuse irregular narrowing of main pancreatic duct, with associated multiple biliary strictures at ERCP.  相似文献   
52.
Painful skeletal metastases are a common problem in cancer patients. Although external beam radiation therapy is the current standard of care for cancer patients who present with localized bone pain, 20–30% of patients treated with this modality do not experience pain relief, and few further options exist for these patients. For many patients with painful metastatic skeletal disease, analgesics remain the only alternative treatment option. Recently, image-guided percutaneous methods of tumor destruction have proven effective for treatment of this difficult problem. This review describes the application, limitations, and effectiveness of percutaneous ablative methods including ethanol, methyl methacrylate, laser-induced interstitial thermotherapy (LITT), cryoablation, and percutaneous radiofrequency ablation (RFA) for palliation of painful skeletal metastases.  相似文献   
53.
目的:明确以IgA沿肾小球毛细血管襻沉积为主的急进性肾小球肾炎的临床与病理特点。方法:分析解放军总医院全军肾脏病研究所收治的1例以IgA沿肾小球毛细血管襻沉积为主的急进性肾小球肾炎病例,分析其临床特点、病理与电镜特征,以及对强化免疫抑制治疗的反应。结果:该病例临床表现为急进性肾炎综合征,肾功能恶化发展迅速。但无肺出血及全身性血管炎症状。血清自身抗体系列、抗GBM抗体与ANCA均为阴性。病理光镜示肾小球环绕型新月体形成,肾小血管无炎症改变。冰冻切片与石蜡微波修复直接免疫荧光示IgA沿肾小球毛细血管襻细颗粒状沉积,间接免疫荧光法检测血清IgA型抗GBM为阴性;电镜示节段性上皮下、基底膜内及系膜区电子致密物沉积。对强化激素冲击与免疫抑制剂治疗效果欠佳。结论:本病例为特殊类型的急进性肾小球肾炎,根据其临床特点、血清学检测、免疫荧光及电镜检查结果,无法归于目前急进性肾炎的分型,对其临床特点应予重视。  相似文献   
54.
Approximately 25 % of mismatch repair (MMR) variants are exonic nucleotide substitutions. Some result in the substitution of one amino acid for another in the protein sequence, so-called missense variants, while others are silent. The interpretation of the effect of missense and silent variants as deleterious or neutral is challenging. Pre-symptomatic testing for clinical use is not recommended for relatives of individuals with variants classified as ‘of uncertain significance’. These relatives, including non-carriers, are considered at high-risk as long as the contribution of the variant to disease causation cannot be determined. This results in continuing anxiety, and the application of potentially unnecessary screening and prophylactic interventions. We encountered a large Irish Lynch syndrome kindred that carries the c.544A>G (p.Arg182Gly) alteration in the MLH1 gene and we undertook to study the variant. The clinical significance of the variant remains unresolved in the literature. Data are presented on cancer incidence within five kindreds with the same germline missense variant in the MLH1 MMR gene. Extensive testing of relevant family members in one kindred, a review of the literature, review of online MMR mutation databases and use of in silico phenotype prediction tools were undertaken to study the significance of this variant. Clinical, histological, immunohistochemical and molecular evidence from these families and other independent clinical and scientific evidence indicates that the MLH1 p.Arg182Gly (c.544A>G) change causes Lynch syndrome and supports reclassification of the variant as pathogenic.  相似文献   
55.
56.
Preface     
Nine patients (4F, 5M) aged 12-17 years with “fear of obesity” were studied with a sequential stimulation test utilizing insulin, LRH, TRH, and L-dopa. The comparative groups were nine female with classic anorexia nervosa, five males with undifferentiated nutritional dwarfing, and nine children (1F, 8M) with constitutional growth delay. The serum TSH, glucose, cortisol, somatotropin, prolactin, LH, and FSH were sampled periodically over 2 hours. Basal T3, T4, transferrin, and Somatomedin-C levels were also obtained. The “fear of obesity” patients did not have any pituitary function changes that were unique. These patients, as well as the comparison groups, revealed a delayed TSH response in proportion to the weight deficit which, when expressed as an integrated response, correlated well to the weight deficit for height (P less than 0.001) and to the ability to recover from hypoglycemia (p less than 0.001). The Somatomedin-C level was low and correlated to the T3 level (p less than 0.05) and not correlated to the elevated Somatotropin levels. The pituitary response to combined stimulation in patients with fear of obesity was determined to be a component of the spectrum starting at normal and proceeding to the extreme undernutrition of anorexia nervosa. Pituitary responsiveness, therefore, changes not as a function of the etiology of the malnutrition, but simply as a function of its severity.  相似文献   
57.
58.
We describe four cases with symptomatic coronary artery fistulas that were treated primarily with endovascular cyanoacrylate embolization. Coils were also used as adjunctive embolic agents in two of these cases. All four cases showed symptomatic improvement after closure of the fistulas. Complications occurred in three cases including transient ST-segment elevation in one, symptomatic pulmonary embolization in a second, and transient pleuritic chest pain, pericarditis and acute renal failure in a third. The technical aspects of all four cases are given together with a review of the use of cyanoacrylate as an embolic material. We conclude that cyanoacrylate embolization could be considered as an alternative technique for the endovascular closure of coronary artery fistulas but must also caution that the use of this embolic agent is hazardous and should be restricted to practitioners experienced in its usage.  相似文献   
59.
This paper reports a systematic review of prompt-fading research, with a focus on experiments comparing two or more prompt-fading procedures. Forty-five articles with 46 experiments met the operationally-defined inclusion criteria. For the selected articles, data on several variables were extracted and analyzed. Research demonstrated that all prompt-fading procedures were generally effective in promoting acquisition of behavior. Stimulus prompting was more effective and efficient when compared to response-prompting procedures. Comparisons of response-prompting procedures yielded variable efficiency results. These outcomes are discussed in terms of the behavioral principles that facilitate transfer of stimulus control from the prompt to the discriminative stimulus, such as blocking and overshadowing. Basic investigations of the role of these behavioral principles might help develop prompt-fading procedures that are consistently effective across participants. Implications for research include suggestions for the development of individualized assessments of stimulus control, similar to the functional analysis methodology.  相似文献   
60.
Animal models of chronic prolactin (PRL) excess have included rats bearing transplantable pituitary tumors that have produced other hypophyseal hormones in addition to PRL. We report characterization of a new model, the Buffalo rat implanted with the MMQ tumor, a line developed from the 7315a line. Rats implanted with the MMQ tumor have serum PRL levels that increase with time and correlate with the estimated volume of the subcutaneous tumor. When rats are killed 4 weeks after implantation, serum PRL levels are strikingly higher in tumor-bearing rats compared with controls (females, 2,723 +/- 266 v 192 +/- 46 ng/mL, P less than .0001; males, 1,637 +/- 213 v 99 +/- 11 ng/mL, P less than .0001). Serum PRL levels measured by the Nb2 lymphoma assay were higher than immunoassay measurements in both tumor-bearing and control Buffalo rats. Sephadex chromatography of serum from tumor-bearing rats showed that most of the PRL immunoreactivity co-eluted with 125I-rPRL. Neither serum growth hormone (GH) nor luteinizing hormone (LH) levels were different from controls in tumor-bearing rats. Female MMQ-bearing rats had lower estradiol levels. At death, the wet weights of adrenal glands, kidneys, and gonads were not affected by the presence of tumor. In contrast, tumor-bearing rats had increased spleen weight and histological evidence of white pulp hyperplasia. The Buffalo rat implanted with the PRL-only MMQ tumor is a promising new tool for the study of chronic hyperprolactinemia.  相似文献   
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