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排序方式: 共有307条查询结果,搜索用时 15 毫秒
91.
目的:报告1例甲状腺相关性眼病的非典型CT扫描表现。方法:一位64岁的中国女性出现复视3mo,无视力模糊。14a前她曾患甲状腺功能亢进症伴多结节甲状腺肿并行甲状腺切除术。眼科检查发现双眼下斜视并向上注视受限。左眼red desaturation并Ⅰ级相对性瞳孔传入障碍。T3,T4和促甲状腺激素(thyroid stimulating hormone,TSH)正常。TSH受体、抗体水平高,与Graves'病一致。磁共振成像(magnetic resonance imaging,MRI)显示双下直肌弥漫性增大,肌腱受累。结果:给予几周期静脉注射甲基强的松龙继之以口服强的松后视力无提高,反之继续下降。行左眼眼眶减压术,术后其左眼视力有所改善。结论:有肌腱受累的眼外肌增大不能排除甲状腺相关性眼眶病(thyroid assciated orbitopathy,TAO)的可能。 相似文献
92.
Objective:
Stenotrophomonas maltophilia is an opportunistic pathogen found predominantly in the enviroment and hospital setting. Invasive procedures and treatment methods, instruments used for diagnosis and irrational antibiotic use play major roles in the spread of this pathogen. The study aimed to evaluate consecutive S maltophilia isolation from bronchoalveolar lavage samples during bronchoscopy procedure during a week.Methods:
Four patients consecutively had S maltophilia isolated during bronchoscopy between September 8 and 15, 2012. The identification of the isolates and their antibiotic susceptibility were studied by automated Vitek version 2.0 (Biomerieux, France) system. The clonal relationship between the isolates was studied by enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR).Results:
Four consecutive S maltophilia isolates had identical band patterns and showed clonal relatedness.Conclusion:
Bronchoscopy is a common invasive procedure that is utilized in chest diseases departments and intensive care units (ICUs). Contamination may take place due to inappropiate use and cause spread of infectious pathogens. In the current study, we detected consecutive S maltophilia strains with identical band patterns isolated within a week. After appropiate disinfection and cleaning procedures, no further isolation was detected. 相似文献93.
Muhammad Aamir Iqbal Maria Malik Abu Zahid Md. Rasidul Islam Ivn D. Arellano-Ramírez Mohammed Al-Bahrani 《RSC advances》2022,12(35):22783
The structural and optoelectronic characteristics of Zn1−xCdxS (x = 0, 0.25, 0.50, 0.75, 1) semiconductors are reported using density functional theory within GGA, EV-GGA, and mBJ functionals. These semiconductors are observed in cubic symmetry at all Cd-concentrations and the lattice constant increases linearly with Cd-concentration while the bulk modulus shows a reverse behavior. These materials are direct bandgap semiconductors at all Cd-concentrations and their bandgap energy decreases from 3.67 eV to 2.59 eV. The isotropic optical properties of these direct bandgap semiconductors vary with Cd concentration as well, with absorption coefficients decreasing and absorbed near-UV light converting to visible blue light. Optical properties like refractive index, dielectric constant, conductivity, extinction coefficient, and reflectance are also displayed and discussed. These results provide useful theoretical understanding for the application of CdZnS semiconductors in photonic, photovoltaic, and optoelectronic devices.This study explores the concentration dependent optoelectronic properties of Zn1−xCdxS (x = 0, 0.25, 0.50, 0.75, 1) cubic direct bandgap semiconductors using DFT within mBJ potential. 相似文献
94.
Two infants presenting with respiratory distress in the first 24 h of life are described. Both patients underwent extensive investigation before the diagnosis of surfactant protein B-deficiency was reached. Both children died within 2 months of birth. Parental consanguinity was known to be a feature in the first case, who proved to have a previously unrecognized mutation of the surfactant protein B gene. In the second case, a history of parental consanguinity was not sought from the Caucasian family, but was later volunteered by the parents themselves. Case 2 proved to have the "common" surfactant protein B-deficient genotype. The key to diagnosis is having a high index of suspicion in any term or near-term newborn with severe respiratory distress; parental consanguinity must be excluded. Surfactant protein B-deficiency can be readily diagnosed from bronchoalveolar lavage specimens; a simple, inexpensive procedure which is well tolerated in newborns. 相似文献
95.
Detection of renal masses: sensitivities and specificities of excretory urography/linear tomography, US, and CT 总被引:4,自引:0,他引:4
Warshauer DM; McCarthy SM; Street L; Bookbinder MJ; Glickman MG; Richter J; Hammers L; Taylor C; Rosenfield AT 《Radiology》1988,169(2):363-365
A prospective blinded study of 201 patients was performed to determine the relative sensitivities and specificities of excretory urography/linear tomography (EU/LT) and ultrasound (US) for the diagnosis of renal parenchymal masses. Computed tomography (CT) was used as a standard. EU/LT permitted detection of 10% of CT-confirmed masses (cystic or solid) less than 1 cm, 21% of lesions greater than or equal to 1 cm but less than 2 cm, 52% of lesions greater than or equal to 2 cm but less than 3 cm, and 85% of lesions 3 cm or more in diameter. US permitted detection of 26% of CT-confirmed lesions less than 1 cm, 60% of lesions greater than or equal to 1 cm but less than 2 cm, 82% of lesions greater than or equal to 2 cm but less than 3 cm, and 85% of lesions 3 cm or more in size. The results confirm the relative insensitivity of EU/LT for masses less than 3 cm in diameter and of US for masses less than 2 cm. Further, they suggest that CT may have a role not only in evaluation of cases in which the urographic or sonographic results are questionable or positive, but also in confirmation of apparently negative urographic findings when clinical suspicion of a lesion is high. 相似文献
96.
97.
Bone marrow in leukemia and aplastic anemia: MR imaging before, during, and after treatment 总被引:2,自引:0,他引:2
Serial magnetic resonance (MR) studies of the cervical bone marrow were performed in five patients undergoing bone marrow transplantation for chronic granulocytic leukemia and in four patients with aplastic anemia who were treated with antilymphocytic globulin. Findings were compared with those from a group of healthy volunteers. Chemical shift imaging techniques were used to exploit the presence of protons in fat and water in the red marrow. Characteristic changes were seen in aplastic anemia before treatment, but derivation of images representing fat and water fractions was necessary to distinguish leukemic marrow. Acute changes during the treatment of leukemia may reflect the effects of chemotherapy and radiation therapy, whereas changes in the chronic phase of both diseases may prove useful in predicting treatment outcome. MR studies are likely to be useful in the assessment and treatment of hematologic disorders. 相似文献
98.
Acute flank pain: comparison of non-contrast-enhanced CT and intravenous urography 总被引:26,自引:2,他引:24
Smith RC; Rosenfield AT; Choe KA; Essenmacher KR; Verga M; Glickman MG; Lange RC 《Radiology》1995,194(3):789
99.
Hunter DW; Castaneda-Zuniga WR; Coleman CC; Young AT; Salomonowitz E; Mercado S; Amplatz K 《Radiology》1984,152(3):631-635
A total of 31 patients with 45 episodes of failing arteriovenous dialysis fistulas was studied. Fistula failure was usually due to venous and/or anastomotic stenosis, often in conjunction with thrombosis. Abnormalities were treated by percutaneous dilation and occasionally streptokinase infusion. Most complications and failures occurred either in patients with recently created fistulas or in those with multiple or long segment stenosis associated with thrombosis. Patients with a single nonobstructing stenosis were very successfully treated with percutaneous techniques, which are the treatment of choice for this condition. 相似文献
100.
In alcoholic liver disease (fatty infiltration, alcoholic cirrhosis), the liver is diffusely abnormal on ultrasound. Changes in size, dilatation of the hepatic veins, and ascites may also occur. The authors conducted a histological correlation of these abnormalities in 22 alcoholic patients and 16 controls, grading the changes on a scale of 0 to 4+ for fat, fibrosis, and necrosis and noting tumor whenever present. Ultrasound detected abnormality in 21 cases (sensitivity = 95%) and correctly identified 15 controls (specificity = 94%). Of the 5 tumors seen, 4 hepatomas were detected and biopsied and 1 metastatic squamous-cell carcinoma was missed. Applications of commercially available A-scan module are considered and its limitations discussed. With the exception of minimal change (1+ fat or fibrosis), ultrasound detected many of the pathological changes seen in alcoholic liver disease. 相似文献