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341.
Magkanas E Detorakis E Nikolakopoulos I Gourtsoyianni S Linardakis M Sidiropoulos P Boumpas D Gourtsoyiannis N 《La Radiologia medica》2011,116(6):858-867
Purpose
This study was undertaken to assess the presence and extent of air trapping (AT) on high-resolution computed tomography (HRCT) in patients with Wegener??s granulomatosis (WG) and to correlate the finding with the inspiratory pattern and bronchial/bronchiolar involvement.Materials and methods
Twenty-one patients (7 M/14 F) with WG underwent inspiratory and expiratory HRCT. Images were evaluated for the presence and extent of AT and for airway involvement (bronchi/bronchioles); the predominant HRCT pattern was also documented. The attenuation difference was measured between the areas of AT on expiration and the same areas on inspiration in order to verify the finding of AT. The extent of AT was calculated by visual scoring and correlated with the predominant inspiratory patterns and bronchial/bronchiolar involvement.Results
AT was found in seven patients (33.3%) and its extent ranged between 3% and 70% (mean 15.8±7). Two patients showed no lesions on inspiratory HRCT, and the only finding was AT on expiration. The attenuation difference between areas of AT on expiration and the same areas on inspiration ranged between 32 and 89 HU. Inspiratory HRCT was pathological in 19 patients (90.4%), and the principal lung patterns were nodular, cavitary or noncavitary (n=7, 38.9%); ground-glass opacities (n=5, 26.3%); masses (n=3, 15.8%); fibrotic (n=3, 15.8%); and consolidation with air bronchogram (n=1, 5.3%). Bronchial and bronchiolar involvement was found in 14 and five patients, respectively. No statistically significant correlation was found between AT extent and the findings on inspiration. In addition, there were no specific patterns that caused higher or lower scores of AT. Moreover, when bronchial or bronchiolar involvement was absent, the mean AT score was statistically significantly higher.Conclusions
Areas of AT represent a new and indirect HRCT finding, ?? and in rare cases the only finding ?? of pulmonary WG. The nonsignificant correlation between AT extent and inspiratory findings may suggest AT as an additional HRCT finding in patients with WG. 相似文献342.
The pancreas in β-thalassemia major: MR imaging features and correlation with iron stores and glucose disturbunces 总被引:1,自引:0,他引:1
Papakonstantinou O Ladis V Kostaridou S Maris T Berdousi H Kattamis C Gourtsoyiannis N 《European radiology》2007,17(6):1535-1543
The study aims at describing the MR features of pancreas in beta-thalassemia major, investigating the relations between MR
findings and glucose disturbances and between hepatic and pancreatic siderosis. Signal intensity ratios of the pancreas and
liver to right paraspinous muscle (P/M, L/M) were retrospectively assessed on abdominal MR imaging studies of 31 transfusion-dependent
patients with beta-thalassemia major undergoing quantification of hepatic siderosis and 10 healthy controls, using T1- (120/4/90),
intermediate in and out of phase - (120/2.7, 4/20), and T2*-(120/15/20) weighted GRE sequences. Using the signal drop of the
liver and pancreas on opposed phase images, we recorded serum ferritin and results of oral glucose tolerance test (OGTT).
Decreased L/M and P/M on at least the T2* sequence were noticed in 31/31 and 30/31 patients, respectively, but no correlation
between P/M and L/M was found. Patients with pathologic OGTT displayed a higher degree of hepatic siderosis (p < 0.04) and
signal drop of pancreas on opposed phase imaging (p < 0.025), implying fatty replacement of pancreas. P/M was neither correlated
with glucose disturbances nor serum ferritin. Iron deposition in the pancreas cannot be predicted by the degree of hepatic
siderosis in beta-thalassemia major. Fatty replacement of the pancreas is common and may be associated with glucose disturbances. 相似文献
343.
The purpose of this study was to provide the required data for the direct calculation of testicular dose resulting from radiotherapy in patients with seminoma. Paraortic (PA) treatment fields and dog-leg (DL) portals including paraortic and ipsilateral pelvic nodes were simulated on a male anthropomorphic phantom equipped with an artificial testicle. Anterior and posterior irradiations were performed for five different PA and DL field dimensions. Dose measurements were carried out using a calibrated ionization chamber. The dependence of testicular dose upon the distance separating the testicle from the treatment volume and upon the tissue thickness at the entrance point of the beam was investigated. A clamshell lead shield was used to reduce testicular dose. The scattered dose to testicle was measured in nine patients using thermoluminescent dosimeters. Phantom and patient exposures were generated with a 6 MV x-ray beam. Linear and nonlinear regression analysis was employed to obtain formulas describing the relation between the radiation dose to an unshielded and/or shielded testicle with the field size and the distance from the inferior field edge. Correction factors showing the variation of testicular dose with the patient thickness along beam axis were found. Bland-Altman statistical analysis showed that testicular dose obtained by the proposed calculation method may differ from the measured dose value by less than 25%. The current study presents a method providing reasonable estimations of testicular dose for individual patients undergoing PA or DL radiotherapy. 相似文献
344.
Isabel Benzel James NC Kew Ramya Viknaraja Fiona Kelly Jacqueline de Belleroche Steven Hirsch Thirza H Sanderson Peter R Maycox 《BMC psychiatry》2008,8(1):1-14
Background
Systematic reviews based on efficacy trials are inconclusive about which second generation antipsychotic drug (SGA) should be preferred in normal clinical practice, and studies with longer duration and more pragmatic designs are called for. Effectiveness studies, also known as naturalistic, pragmatic, practical or real life studies, adhere to these principles as they aim to mimic daily clinical practice and have longer follow-up.Objective
To review the head-to-head effectiveness of SGAs in the domains of global outcomes, symptoms of disease, and tolerability.Methods
Searches were made in Embase, PubMED, and the Cochrane central register of controlled trials for effectiveness studies published from 1980 to 2008, week 1. Different combinations of the keywords antipsychotic*, neuroleptic* AND open, pragmatic, practical, naturalistic, real life, effectiveness, side effect*, unwanted effect*, tolera* AND compar* AND random* were used.Results
Sixteen different reports of randomized head-to-head comparisons of SGA effectiveness were located. There were differences regarding sample sizes, inclusion criteria and follow-up periods, as well as sources of financial sponsorship. In acute-phase and first-episode patients no differences between the SGAs were disclosed regarding alleviating symptoms of disease. Olanzapine was associated with more weight gain and adverse effects on serum lipids. In the chronic phase patients olanzapine groups had longer time to discontinuation of treatment and better treatment adherence compared to other SGAs. The majority of studies found no differences between the SGAs in alleviating symptoms of psychosis in chronically ill patients. Olanzapine was associated with more metabolic adverse effects compared to the others SGAs. There were surprisingly few between-drug differences regarding side effects. First generation antipsychotics were associated with lower total mental health care costs in 2 of 3 studies on chronically ill patients, but were also associated with more extrapyramidal side effects compared to the SGAs in several studies.Conclusion
In chronically ill patients olanzapine may have an advantage over other SGAs regarding longer time to treatment discontinuation and better drug adherence, but the drug is also associated with more metabolic side effects. More effectiveness studies on first-episode psychosis are needed. 相似文献345.
目的 探讨腹腔镜在外科治疗门静脉高压症手术风险及手术技巧.方法 自 2011 年 6 月以来,46 例诊断为肝炎肝硬变、门静脉高压症、食管胃底静脉曲张,肝功能分级 Child A 级 32 例,B 级 14 例.术前胃镜检查了解食管胃底静脉曲张;门静脉彩超,了解门静脉有无血栓;上腹部 CT 增强扫描,了解脾脏大小,脾动、静脉走行,二级脾蒂分叉部位,脾门以及胃底、贲门周围曲张静脉分布情况.采用 4 孔法,取脐上 10 mm 戳孔为腹腔镜观察孔,左锁骨中线约与脐平线 12 mm 戳孔,为主操作孔;剑突左侧肋缘下 2 cm 处 5 mm 戳孔、左腋前线约与脐平线 12 mm 戳孔为辅操作孔,术者、一助均位于患者右侧.LS 技术操作我们采用前入路与侧入路结合方法,离断脾动脉、胃短血管时用前入路,游离脾肾、脾膈韧带,离断脾蒂时运用侧入路;贲门周围血管离断采用前入路.结果 全腹腔镜成功实施 38 例肝硬化门静脉高压症脾切除加贲门周围血管离断术,7 例术中出现不可控出血中转,1 例慢性胰腺炎术中无法分离出脾动脉中转.手术时间 142 ~ 218 min,平均( 167 ± 44 ) min,术中出血80 ~ 280 ml,平均( 113 ± 76 ) ml.采用预先结扎脾动脉,Endo Cut 闭合切割一级脾蒂或二级脾蒂,无出血、胰漏并发症,无死亡病例.术后第 2 天拔除胃管,第 3 天拔除腹腔引流管,术后 7 ~ 12 d 出院.结论 通过上腹部 CT,谨慎进行贲门周围血管离断术手术风险评估,正确的操作步骤,准确的分离层面,娴熟的腹腔镜下分离技巧,处理脾蒂血管动作精细,预防出血,保持视野清晰,尽管风险很大,腹腔镜手术治疗门静脉高压症还是安全、可行的. 相似文献
346.
Holly Powell Kennedy CNM PhD COL USAR Trisha Farrell CNM MS CDR NC USN Regina Paden CNM MS Maj USAF NC Shannon Hill CNM MSN Maj USAF NC Rima Jolivet CNM MSN MPH Jacqueline Willetts RN MSN GNP Sharon Schindler Rising CNM MSN 《Journal of Midwifery & Women's Health》2009,54(3):176-183
The military has recognized that health and quality of life for service members are closely tied to the resources for their families, including how they are cared for during pregnancy and childbirth. However, there has been little examination of women's experience with different models of prenatal care (PNC) in military settings. The purpose of this article is to describe the results of a qualitative study of women's experiences with the CenteringPregnancy model of group PNC compared to individual PNC in two military health care settings. This clinical trial enrolled 322 women who were randomized into group or individual PNC at two military treatment facilities. Qualitative interviews were completed with 234 women during the postpartum period. Interpretative narrative and thematic analysis was used to identify three themes: 1) “I wasn't alone”—the experience with group PNC; 2) “I liked it but…”—recommendations to improve group PNC; and 3) “They really need to listen”—general concerns across the sample about PNC. Greatest concerns of women in individual PNC included lack of continuity and time with the provider. Our military families must be assured that their health care system meets their needs through personal and family‐centered care. Group PNC offers the potential for continuity of provider while also offering community with other women. In the process, women gain knowledge and power as a health care consumer. 相似文献
347.
The radiological features of small intestinal lymphoma are described in 11 patients examined using the small bowel enema technique. The signs include luminal narrowing with mucosal destruction and occasionally shouldering of the margins and stricture formation, broad based ulceration, cavitation, non-specific thickening of the valvulae conniventes, discrete intraluminal filling defects, and a mass. In one patient, small nodules were scattered throughout the small intestine. Aneurysmal dilatation of a segment of intestine was seen in one case and an extraluminal mesenteric mass in another. A combination of different signs was a frequent finding and multiple intestinal lesions were present in four cases. Predisposing factors were present in five cases including coeliac disease, chronic lymphatic leukaemia, immunoproliferative small intestinal (alpha-chain) disease and previous extraintestinal lymphoma. In another patient there was evidence of extraintestinal lymphoma at the time of presentation. 相似文献
348.
应用密度梯度离心结合免疫磁珠法富集孕妇外周血中胎儿NRBC的实验研究 总被引:2,自引:0,他引:2
目的研究利用不连续密度梯度离心结合免疫磁珠方法,分选孕妇外周血中的胎儿有核红细胞(NRBC)。方法采集21名孕周在12-28周的孕妇外周血10ml,经不连续密度梯度离心后,再用免疫磁珠法分选和富集胎儿NRBC,同时对富集前后的孕妇外周血进行瑞氏染色和胎儿血红蛋白(fetal hemoglobin,HbF)特异性抗体标记、识别。结果未经分选、富集,21名孕妇外周血有核细胞层涂片经瑞氏染色检查均未发现NRBC;梯度离心富集后21名孕妇中有11例外周血有核细胞涂片找到1~8个NRBC;再经免疫磁珠分离后有12例涂片发现1~7个NRBC,同时进行HbF特异性抗体标记,证实其NRBC阳性涂片中均存在胎源性NRBC。结论本研究初步建立了分选、富集胎儿NRBC的实验方法,通过进一步的方法学改进,有望用于产前基因筛查的研究。 相似文献
349.
350.