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41.
《Amyloid》2013,20(3):192-198
Gastrointestinal (GI) dysfunction is a common complication of familial amyloidotic polyneuropathy (FAP). In previous reports, a decreased content of small and large intestinal endocrine cells has been found in patients with FAP and it has been suggested that this may contribute to the development of GI disturbances. The aim of the present study was to investigate the endocrine cell content in the stomach and duodenum of FAP patients, and to correlate the findings with gastric emptying.

Fifteen patients with FAP were included in the study. Twenty-eight subjects with macroscopically and histologically normal mucosa were used as controls for endocrine cell contents and 14 healthy subjects for gastric scintigraphy. The endocrine cells were identified by immunohis-tochemistry and quantified with image analysis. Gastric emptying time was detected by scintigraphy andendoscopy.

The number of chromogranin A-immunoreactive (IR) cells was reduced in all investigated parts of the GI tract except bulbus duodeni. Gastrin/CCK cell content was reduced in duodenum, but tended to be increased in antrum of the stomach (P=0.07). Otherwise, the content of all other endocrine cells types in the upper GI tract was reduced compared with controls. A correlation with malnutrition was found for gastric inhibitory polypeptide and secretin cell content in bulbus duodeni. Gastric scintigraphy disclosed delayed gastric emptying of solid food, but the finding was not correlated to the decreased content of neuroendocrine cells. The severity of endocrine cell depletion was not correlated to duration of GI disturbances.

The present study showed that the endocrine cells of the stomach are affected in FAP patients and that the abnormalities in the upper GI endocrine cells occur early during the course of the disease.  相似文献   
42.
Abstract

We report a case of nodular-type muscular sarcoidosis with no systemic symptoms. Thallium-201 scintigraphy showed intense uptake in the muscular lesion mimicking malignant soft tissue tumor. Magnetic resonance imaging (MRI) demonstrated characteristic signal patterns of peripheral high intensity with central low intensity (“three stripes” pattern). Microscopy revealed sarcoid granuloma with typical histopathological characteristics. Propionibacterium acnes was detected on polymerase chain reaction analysis of the excised tissue.  相似文献   
43.
~(99m)锝腮腺动态显像对舍格伦综合征的诊断价值   总被引:4,自引:0,他引:4       下载免费PDF全文
目的 探讨^99m锝腮腺动态显像对诊断舍格伦征的价值。方法 应用^99m锝对临床诊断为舍格伦综合征的52例患者进行腮腺动态显像,将所得的结果应用计算机ROI程序进行定量分析和动态曲线分析,结果 腮腺外形较正常大者46例(88.4%)肿大腮腺轮廓清晰28例(53.85%)轮廓模糊18例(34.62%)腮腺功能正常7例(13.46%)轻度受损15例(28.84%)中8度受损17例(32.69%),重度  相似文献   
44.
Technetium-labeled cardiac scintigraphy (i.e., Tc-PYP scan) has been repurposed for the diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM). Validated in cohorts of patients with heart failure and echocardiographic and/or cardiac magnetic resonance imaging findings suggestive of cardiac amyloidosis, cardiac scintigraphy can confirm the diagnosis of ATTR-CM only when combined with blood and urine testing to exclude a monoclonal protein. Multisocietal guidelines support the nonbiopsy diagnosis of ATTR-CM using cardiac scintigraphy, yet emphasize its use in the appropriate clinical context and the crucial need to rule out light chain amyloid cardiomyopathy. Although increased awareness of ATTR-CM and the advent of effective therapy have led to rapid adoption of diagnostic scintigraphy, there is heterogeneity in adherence to consensus guidelines. This perspective outlines clinical scenarios wherein findings on technetium-labeled cardiac scintigraphy have been misinterpreted, reviews causes of false-negative and false-positive results, and provides strategies to avoid costly and potentially fatal misdiagnoses.  相似文献   
45.
Sestamibi allows ECG-gated acquisition and similarly to radionuclide angiography a time-activity curve from a defined myocardial region can be derived and analysed. Diastolic (peak relaxation velocity) and systolic (per cent thickening) functional parameters from Sestamibi ECG-gated acquisition were obtained; this data were compared in 10 patients with radionuclide angiographic data (peak filling rate and ejection fraction, respectively). A high correlation was found between peak relaxation velocity and peak filling rate (r = 0.792), while no significant correlation was found between thickening and ejection fraction (r=0.577). Sestamibi parameters were calculated in 15 patients with known or suspected coronary artery disease and compared with those obtained in 10 normal subjects. In regions supplied by stenotic vessels the average values of peak relaxation velocity and thickening were significantly lower than those obtained in control subjects in the corresponding vascular territory. The average regional values of the diastolic parameter were significantly lower than the corresponding normal range also in regions with preserved systolic function, i.e. with thickening values within 1SD from the mean value of normals.In conclusion, from the ECG-gated acquisition of Sestamibi regional diastolic and systolic functional parameter may be derived; this completes the spectrum of information that can be obtained by a single injection of tracer.Abbreviations EDc end-diastolic counts - EDV end-diastolic volume - EF% ejection fraction - ESc end-systolic counts - ESV end-systolic volume - PFR peak filling rate - PRV peak relaxation velocity - TH% percent thickening  相似文献   
46.
Thallium-201 (201T1) washout analysis was proposed as an adjunctive tool to improve the detection of coronary artery disease (CAD). Since reproducibility of 201T1 washout in dipyridamole (DPM) stress studies is unknown, this item was evaluated in 32 patients (24 with CAD, 8 without CAD), who were scintigraphed twice within 1–2 weeks. At 2 minutes following DPM infusion (0.5 mg/kg/5 min), 2 mCi 201T1 were injected. Global and segmental washout were calculated by comparing circumferential profiles of respective background-corrected stress (left anterior oblique (LAO) 45°: 8 min postinfusion (p.i.), 35 min p.i.; anterior (ANT): 17 min p.i.; LAO 70°: 26 min p.i.) and redistribution (4 h p.i.) images. Whereas visual findings were comparable for study I and II, reproducibility of 201T1 washout was low, indicated by comparing variances among patients with variance between studies, which were 28.8 and 71.2% of total variance, respectively. Mean differences of segmental washout between the studies ranged from 9.75 to 19.24% with only minor differences with regard to the different views and segments evaluated. Variability was lower using the intermediate instead of the initial scintigram as reference for the redistribution image (12.87±11.64% vs. 18.59±14.43%, n = 85; p<0.01). Variability was higher for nonstenosed compared to stenosed segments (14.54 ± 11.41%, n=32 vs. 9.89±8.03%, n=28, p<0.05). Correspondent with results of visual interpretation, variance of relative differences of washout values between neighboring segments was lower than variance statistically expected from variability of washout values between study I and II (12.79%, n=216 vs. 21.55%, n=270; F=2.76, p<0.01). It is suggested, that considerable washout variability might explain the controversially discussed diagnostic value of 201T1 washout analysis in DPM stress studies.  相似文献   
47.
Summary In healthy humans, the increase in arterial blood pressure seen in patients with autonomic dysfunction in response to exogenous vasopressin (AVP) is abolished. We tested the hypothesis that redistribution of blood from the intra- to the extrathoracic vascular compartment might contribute to this buffer response. Regional distribution of99mTc labeled autologous red cells was assessed in healthy supine volunteers (n=7) during arginine-vasopressin administration (1 ng·kg–1 bolus i.v. followed by a 14-min infusion of 3 ng·kg–1·min–1), along with arterial and central venous pressures, and heart rate. Exogenous vasopressin increased plasma vasopressin concentration from 4.0±1.4 SEM to 91 pg·ml–1±12. Thoracic counts increased slightly but significantly by 2.2%±0.9, while global abdominal counts remained unchanged. Most surprisingly, counts in the liver markedly increased (+8.1%±1.8, p=0.02), but significantly decreased in the spleen (–3.1%±1.4). Intestinal (–2.5%±2.4) and limb counts did not change significantly. Consistent with the increase in thoracic counts centralvenous pressure increased from 3.6 mm Hg±1 to 4.7±1 (p=0.02), while arterial pressure and heart rate did not change. All changes reversed towards baseline when vasopressin administration ceased. Thus, in humans with an intact autonomic system, vasopressin, at concentrations observed during hypotension, increases liver and, albeit to a small extent, also thoracic blood volume, but decreases splenic blood content. These results 1) are incompatible with the hypothesis that AVP induces a shift of blood from intra- to extrathoracic capacitance vessels, and 2) show that AVP increases rather than decreases central blood volume.  相似文献   
48.
Tracheobronchopathia osteochondroplastica (TO) is a rare disorder with unknown aetiology. We report one case of TO in a patient with non-Hodgkin pulmonary lymphoma and benign epidermal and trichylemmal cysts on the periorbital region and scalp. To the authors' knowledge, the coincidence of these processes has never been described before. The case was evaluated with conventional X-ray, computed tomography, magnetic resonance imaging, fibre-optic bronchoscopy with 2 months interval, histopathological evaluation, Tc-99 m MDP bone scintigraphy and microbiological studies including PCR testing of bronchial biopsy and lavage specimens for Mycobacterium tuberculosis. Additionally, case reports of TO in the Turkish literature are summarized.  相似文献   
49.
ObjectivesThis study sought to describe worldwide variations in the use of myocardial perfusion imaging hardware, software, and imaging protocols and their impact on radiation effective dose (ED).BackgroundConcerns about long-term effects of ionizing radiation have prompted efforts to identify strategies for dose optimization in myocardial perfusion scintigraphy. Studies have increasingly shown opportunities for dose reduction using newer technologies and optimized protocols.MethodsData were submitted voluntarily to the INCAPS (International Atomic Energy Agency Nuclear Cardiology Protocols Study) registry, a multinational, cross-sectional study comprising 7,911 imaging studies from 308 labs in 65 countries. The study compared regional use of camera technologies, advanced post-processing software, and protocol characteristics and analyzed the influence of each factor on ED.ResultsCadmium-zinc-telluride and positron emission tomography (PET) cameras were used in 10% (regional range 0% to 26%) and 6% (regional range 0% to 17%) of studies worldwide. Attenuation correction was used in 26% of cases (range 10% to 57%), and advanced post-processing software was used in 38% of cases (range 26% to 64%). Stress-first single-photon emission computed tomography (SPECT) imaging comprised nearly 20% of cases from all world regions, except North America, where it was used in just 7% of cases. Factors associated with lower ED and odds ratio for achieving radiation dose ≤9 mSv included use of cadmium-zinc-telluride, PET, advanced post-processing software, and stress- or rest-only imaging. Overall, 39% of all studies (97% PET and 35% SPECT) were ≤9 mSv, while just 6% of all studies (32% PET and 4% SPECT) achieved a dose ≤3 mSv.ConclusionsNewer-technology cameras, advanced software, and stress-only protocols were associated with reduced ED, but worldwide adoption of these practices was generally low and varied significantly between regions. The implementation of dose-optimizing technologies and protocols offers an opportunity to reduce patient radiation exposure across all world regions.  相似文献   
50.
Myocardial perfusion scintigraphy with thallium-201 was performed in 33 subjects (mean age 45 years, range 28-61) with exercise-induced, rate-dependent left bundle branch block (LBBB) in order to assess both the value of Thallium-201 myocardial imaging for the diagnosis of coronary artery disease (CAD) and the pathogenesis (ischaemic or not) of the conduction defect. Of the 33 patients evaluated, 16 had chest pain suggestive of CAD and 17 were asymptomatic. None had a history of prior myocardial infarction or clinical and echocardiographic signs of heart disease. LBBB appeared at a heart rate ranging from 70 to 160 b.min-1. Eighteen patients showed repolarization abnormalities (ST segment depression with deep inverted T waves) compatible with ischaemia, after QRS normalization. Thallium-201 myocardial uptake was normal in 12 subjects; in the remaining 21, reversible Thallium-201 defects were demonstrated in the septum (18 patients), septum and apex (2), and septum and infero-apical wall (1). No patient had irreversible defects and all had normal coronary angiography, with negative ergonovine tests for coronary artery spasm. The patients were followed up for a mean of 43 months (range 16-80). One patient died from sudden death, but no cardiac event occurred in the other patients. In conclusion, exercise Thallium-201 myocardial scintigraphy showed a high prevalence (64%) of reversible perfusion defects in a group of patients with exercise-induced LBBB without any evidence of CAD at angiography or coronary spasm at ergonovine test. Moreover, follow-up showed a relatively low rate of major cardiac events.  相似文献   
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