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91.
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Follicular dendritic cell tumor (FDCT) is a rare tumor mainly located in laterocervical lymph nodes. We report one case of mediastinal FDCT associated with a history of bullous skin disease and clinically obvious immunosuppression. This tumor was characterized by heavy mast cell infiltration. Mast cells were in close relationship with tumor cells as demonstrated by ultrastructural examination and their presence are probably related with the strong expression of mast cell chemoattractants as fraktalkine and stromal cell-derived factor-1α by tumor cells. The long follow-up period of more than 17 years allowed to us assess the relatively indolent evolution of this tumor characterized by three slowly growing local recurrences without metastasis.  相似文献   
93.
Diffusion-weighted MR imaging of the liver of hepatitis C patients   总被引:17,自引:0,他引:17  
Magnetic resonance diffusion-weighted imaging (DWI) of the liver was investigated to determine whether this method could be used to differentiate between the stages of fibrosis and inflammation for hepatitis C viral infection. DWI data were recorded for 18 hepatitis C patients and 10 control subjects using a modified pulse sequence allowing a 52 ms echo time delay. Acquisitions were performed with breath holding using five different b gradient factor values ranging between 50 and 250 s/mm(2) and in the three axes. Apparent diffusion coefficient (ADC) values were measured from a 5.7 cm(2) area in the central region of the liver. The inflammation and fibrosis grades were evaluated histologically on a biopsy sample. The mean ADC values were 2.30 +/- 1.28 x 10(-3) and 1.79 +/- 0.25 x 10(-3) mm(2)/s for hepatitis C patients and control subjects, respectively. Using our technique, no correlation could be found between the ADC values and the inflammation or fibrosis scores, indicating that tissue changes produced by hepatitis C do not appear to be quantifiable by DWI.  相似文献   
94.
For patients who require postoperative radiotherapy after endoscopic resection of skull base tumors, proton therapy with pencil beam scanning (PBS) may allow sparing of normal tissue compared to intensity‐modulated photon radiation (IMRT). We compared PBS and IMRT radiation plans in the preoperative and postoperative settings for two patients with advanced skull base tumors following endoscopic resection. The benefits of PBS over IMRT appear greater in the postoperative setting following endoscopic resection with improved sparing of critical organs at risk. The multidisciplinary approach of endoscopic resection followed by PBS represents a treatment paradigm with potential for improvements in toxicity reduction. Laryngoscope, 129:1313–1317, 2019  相似文献   
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We evaluated the usefulness of blood group genotyping as a supplement to hemagglutination to determine the red blood cell (RBC) antigen profile of polytransfused patients with hematological diseases and renal failure. Seventy‐nine patients were selected. They all received more than three units of blood and eight (10%) had already clinical significant alloantibodies occurring alone or in combination against Rh, K, Fya, and Di antigens. DNA was prepared from blood samples and RHCE*E/e, KEL*01/KEL*02, FY*01/FY*02 and JK*01/JK*02 alleles were determined by using PCR‐RFLP. RHD*/RHD*Ψ and RHCE*C/c were tested using multiplex PCR. Discrepancies for Rh, Kell, Duffy, and Kidd systems were found between the phenotype and genotype‐derived phenotype in 16 of the 38 chronically transfused patients. The genotypes of these patients were confirmed by DNA array analysis (HEA Beadchip?; Bioarray Solutions, Warren, NJ). Genotyping was very important for the determination of the true blood groups of the polytransfused patients, helped in the identification of suspected alloantibodies and in the selection of antigen‐negative RBCs for transfusion. J. Clin. Lab. Anal. 24:311–316, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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The objective of this study was to investigate bacterial resistance trends, infection sites and the relationship between resistance and admittance to the intensive care unit (ICU). A total of 53,316 bacteria identified between 1999 and 2008 were evaluated. Multidrug resistance was characterized when gram-negative bacilli (GNB) presented resistance to two or more classes of antibiotics. Gram-positive cocci (CPC) were assessed for resistance to penicillin, oxacillin and vancomycin. GNB were the most common (66.1%) isolate. There was a 3.7-fold overall increase in multidrug resistant GNB over the study period; Acinetobacter baumanii and Staphylococcus aureus were the most prevalent. Highest increases were recorded for Klebsiella pneumoniae (14.6-fold) and enterococci (73-fold). The resistance rates for GNB and GPC were 36% and 51.7%, respectively. Most multidrug resistant GNB and GPC were recovered from ICU patients (p-value < 0.001). Vancomycin-resistant enterococci were isolated during this decade with an increase of 18.7% by 2008. These data confirm the worldwide trend in multidrug bacterial resistance.  相似文献   
99.
The aim of this study is to report our experience with a novel technique, the hysteroscopic morcellator (HM), for removal of intrauterine myomas and polyps. We performed a retrospective study on 315 women undergoing operative hysteroscopy with the HM in our university-affiliated teaching hospital. We collected data on installation and operating times, fluid deficit, peri- and postoperative complications. In 37 patients undergoing myomectomy with the HM, mean installation time was 8.7 min, mean operating time, 18.2 min, and median fluid deficit, 440 mL. Three out of 37 HM procedures were converted to resectoscopy, related to a type 2 myoma. In 278 patients, mean installation and operating times for polypectomy with the HM were 7.3 min and 6.6 min, respectively. All procedures were uneventful. Implementation of the HM for removal of type 0 and 1 myomas ≤3 cm, and removal of polyps appears safe and effective.  相似文献   
100.
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