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51.
Solitary fibrous tumors (SFT) have recently been established to be of mesenchymal origin. Although there are numerous reports of SFTs arising from the pleura, reports of the tumor arising from extrapleural sites are comparatively rare [Fletcher CDM, Unni K, Mertens F (eds) World Health Organization classification of tumors, pathology & genetics, tumors of soft tissue and bone. IARC Press, Lyon, pp 86–901, 2002]. We report a case of SFT arising in the inguinal region.  相似文献   
52.
BACKGROUND: We describe immunomodulatory effects of FK734, a humanized version of a mouse anti-human CD28 mAb (clone TN228), in vitro and in a chimeric human-mouse model of allograft rejection. METHODS: Cytokine production and proliferation were assessed in a mixed lymphocyte reaction containing FK734, human T cells, and endothelial cells or monocytes. FK734 was also administered to SCID mice engrafted with human skin and adoptively transferred with human peripheral blood mononuclear cells allogeneic to the skin graft. RESULTS: In vitro, FK734 enhanced secretion of interleukin-2 and interferon-gamma as well as proliferation of CD4+ and CD8+ T cells stimulated by allogeneic human leukocyte antigen (HLA)-DR+ human umbilical vein endothelial cells (which lack B7 molecules and FcgammaRs) or by blood monocytes (which express low levels of B7 molecules and FcgammaRs) compared with control mAb, but these effects were significantly smaller than those provided by mAb 28.2, a stimulatory mouse anti-human CD28 mAb, at comparable concentrations. However, FK734 generally inhibited cytokine secretion and T cell proliferation in cocultures with human umbilical vein endothelial cells transduced to express CD86. In vivo using SCID/beige mice bearing human skin with adoptively transferred peripheral blood mononuclear cells, administration of FK734 protected human endothelial cell-lined microvessels, significantly but incompletely reducing endothelial cell injury and T cell infiltration into the graft one or two weeks later. CONCLUSIONS: FK734 is a partial agonist of CD28 signaling that can reduce human T cell alloresponses in the presence of strong costimulation by B7 molecules in vitro and can reduce T cell-mediated skin allograft rejection in vivo.  相似文献   
53.
The purpose of this study was to explore risk factors affecting the incidence of chronic kidney disease (CKD) in general population. We conducted a 10-year follow-up study with 123 764 (male: 41 012, female: 82 752) adults aged 40 years and over who received community-based annual examinations. The primary outcome for the analysis was the development of CKD during the follow-up period. Predictors for the development of CKD were obtained by the significant hazard ratios (HR) in Cox regression model by sex. During the follow-up period, 4307 subjects (male: 2048, female: 2259) developed CKD stage I or II, and 19 411 subjects (male: 4257, female: 15 154) developed CKD stage III or higher. The baseline-adjusted predictor of developing CKD included age, glomerular filtration rate, hematuria, hypertension, diabetes, serum lipids, obesity, smoking status, and consumption of alcohol. Treated diabetes in male subjects, and treated hypertension, systolic blood pressure >160 mm Hg and/or diastolic blood pressure >100 mm Hg, diabetes, and treated diabetes in female subjects were associated with more than a doubling of the HR. For the development of CKD stage III or higher, proteinuria of >or= + +, and proteinuria and hematuria were associated with more than a doubling of the HR in male subjects. The prevalence of newly developed CKD over 10 years was 23 718 subjects (19.2%) in adults. This study suggested that not only hypertension and diabetes but also several metabolic abnormalities were independent risk factors for developing CKD.  相似文献   
54.
 A 15-year-old girl who developed traumatic iliacus hematoma and complete paralysis of the quadriceps muscle is reported. The current case and literature review revealed that incomplete quadriceps paralysis associated with traumatic iliacus hematoma is likely to progress to complete paralysis in days or weeks as a result of increased intracompartmental pressure. However, surgical decompression of the femoral nerve could produce good results even in patients who have complete quadriceps paralysis preoperatively. Received: April 9, 2002 / Accepted: June 28, 2002 Offprint requests to: K. Tamai  相似文献   
55.
18F‐fluoride positron emission tomography (18F‐fluoride PET) is a functional imaging modality used primarily to detect increased bone metabolism. Increased 18F‐fluoride PET uptake suggests an association between increased bone metabolism and load stress at the subchondral level. This study therefore examined the relationship between equivalent stress distribution calculated by finite element analysis and 18F‐fluoride PET uptake in patients with hip osteoarthritis. The study examined 34 hips of 17 patients who presented to our clinic with hip pain, and were diagnosed with osteoarthritis or pre‐osteoarthritis. The hips with trauma, infection, or bone metastasis of cancer were excluded. Three‐dimensional models of each hip were created from computed tomography data to calculate the maximum equivalent stress by finite element analysis, which was compared with the maximum standardized uptake value (SUVmax) examined by 18F‐fluoride PET. The SUVmax and equivalent stress were correlated (Spearman's rank correlation coefficient ρ = 0.752), and higher equivalent stress values were noted in higher SUVmax patients. The correlation between SUVmax and maximum equivalent stress in osteoarthritic hips suggests the possibility that 18F‐fluoride PET detect increased bone metabolism at sites of stress concentration. This study demonstrates the correlation between mechanical stress and bone remodeling acceleration in hip osteoarthritis. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:78–83, 2015.  相似文献   
56.
Podocytes are critically involved in the maintenance of the glomerular filtration barrier and are key targets of injury in many glomerular diseases. Chronic injury leads to progressive loss of podocytes, glomerulosclerosis, and renal failure. Thus, it is essential to maintain podocyte survival and avoid apoptosis after acute glomerular injury. In normal glomeruli, podocyte survival is mediated via nephrin-dependent Akt signaling. In several glomerular diseases, nephrin expression decreases and podocyte survival correlates with increased vascular endothelial growth factor (VEGF) signaling. How VEGF signaling contributes to podocyte survival and prevents apoptosis remains unknown. We show here that Gα–interacting, vesicle-associated protein (GIV)/girdin mediates VEGF receptor 2 (VEGFR2) signaling and compensates for nephrin loss. In puromycin aminonucleoside nephrosis (PAN), GIV expression increased, GIV was phosphorylated by VEGFR2, and p-GIV bound and activated Gαi3 and enhanced downstream Akt2, mammalian target of rapamycin complex 1 (mTORC1), and mammalian target of rapamycin complex-2 (mTORC2) signaling. In GIV-depleted podocytes, VEGF-induced Akt activation was abolished, apoptosis was triggered, and cell migration was impaired. These effects were reversed by introducing GIV but not a GIV mutant that cannot activate Gαi3. Our data indicate that after PAN injury, VEGF promotes podocyte survival by triggering assembly of an activated VEGFR2/GIV/Gαi3 signaling complex and enhancing downstream PI3K/Akt survival signaling. Because of its important role in promoting podocyte survival, GIV may represent a novel target for therapeutic intervention in the nephrotic syndrome and other proteinuric diseases.  相似文献   
57.
Chondroblastoma of the temporal bone   总被引:2,自引:0,他引:2  
A rare case of chondroblastoma arising from the temporal bone that occurred in a 60-year-old woman is reported. The tumor appeared well demarcated and osteolytic on the radiographs. CT scan clearly depicted marginal and central calcification in the tumor. MR imaging demonstrated two components in the tumor: a solid component with predominantly low signal intensities on both T1- and T2-weighted sequences, and a multilocular cystic component with T1- and T2-elongation and fluid-fluid levels on the T2-weighted images. Postcontrast MR imaging revealed marked enhancement in the solid component and the septa of the cystic component.  相似文献   
58.
Total arch replacement using the frozen elephant trunk procedure is performed for true lumen expansion of the descending aorta in patients with type A acute aortic dissection. However, the remodelling effect of the frozen elephant trunk on the dissected descending aorta is unclear. We aimed to evaluate the effect of the frozen elephant trunk on postoperative descending aortic remodelling after surgery. Between December 2012 and January 2020, we retrospectively investigated 24 patients who underwent total arch replacement using the frozen elephant trunk for type A acute aortic dissection. Remodelling of the descending aorta was evaluated using computed tomography. The aortic remodelling effect, based on aortic true lumen ratio, was determined for (i) DeBakey type (type I versus type III retrograde); (ii) thoracic endovascular aneurysm repair reintervention status (reintervention versus no reintervention); and (iii) stent length of the frozen elephant trunk (60 vs 90 mm). Postoperative true lumen ratio significantly increased in the type I dissection group. The true lumen ratio in the no-reintervention group, which had many patients with the type I dissection, significantly increased after the frozen elephant trunk. Aortic remodelling due to the frozen elephant trunk can be expected after type I acute aortic dissections.  相似文献   
59.
Objective: To determine the relationship between physical findings, wheelchair sitting time, and interface pressure on ischial region in subjects with spinal cord injury (SCI).Design: Cross-sectional study.Setting: Rehabilitation center in Japan.Participants: Manual wheelchair users with chronic SCI (n = 45).Interventions: Pressure ulcers (PU) were diagnosed by inspection, palpation, and ultrasonography. Self-reports were obtained on wheelchair sitting time and pressure mapping was recorded while the subject was seated on the wheelchair.Outcome measures: Subjects were divided into those with ultrasonographically low-echoic lesions (PU-positive group, n = 11) and no such lesions (PU-negative group, n = 34). Outcome measures included wheelchair sitting time and interface pressure at bilateral ischial regions.Results: Using ultrasonography, 13 low-echoic lesions were identified in 11 subjects of the PU-positive group. The pressure duration was longer and interface pressure was significantly higher in subjects of the PU-positive group compared with those of the PU-negative group (P < 0.05 and P < 0.001, respectively).Conclusions: This is the first study to evaluate the interrelationship between physical findings, sitting time, and ultrasonographically measured interface pressure on ischial region area in subjects with spinal cord injury. To prevent pressure ulcers, we recommend avoidance of prolonged wheelchair sitting and measures that can reduce the interface pressure. These variables should be carefully tailored to the needs of the individual subjects with SCI.  相似文献   
60.
BACKGROUND/AIM: Treatment for dissemination of hepatocellular carcinoma to the pleura and diaphragm following percutaneous needle biopsy has not been established. METHODS: The case of a 57-year-old man who underwent percutaneous needle biopsy for liver tumor is presented. RESULTS: Ten months after resection of the tumor (moderately differentiated hepatocellular carcinoma), masses in the right pleural cavity and on the diaphragm were detected by computed tomography. Resections of the masses with surrounding tissue and the diaphragm and wedge resection of the right lung were performed. A wide range of the pleura and the diaphragm was coagulated with an argon beam coagulator. The patient is in good health without recurrence 4 years after the operation. CONCLUSION: Aggressive surgical treatment should be considered for patients with dissemination of hepatocellular carcinoma by needle biopsy when the lesions are limited.  相似文献   
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