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991.
992.

Purpose

Acoustic radiation force (ARF) elastography has recently become available. The previous animal studies have revealed lung injuries induced by diagnostic ultrasound, but the effects on the lung resulting from exposure to ultrasound with ARF are unknown. This study aimed to assess the risk of lung injury associated with ultrasound with ARF.

Methods

A focused 2.5-MHz transducer that emits ultrasound with ARF was used. A rabbit was anesthetized, and the transducer was placed in the right subcostal region. Exposure settings of mechanical index (MI) 0.80, pulse duration 10 ms, pulse repetition time 5 s, and exposure time 150 s were applied.

Results

One red spot (7 × 6 mm) was observed on the surface of the right lung corresponding to the area of exposure. Alveolar hemorrhage was observed microscopically. This lesion was visible across a range of 20–170 μm in depth from the pleural surface.

Conclusion

The first example of lung hemorrhage induced by ultrasound with ARF was observed in this study. This observation suggests the possibility of lung injury in humans when ARF elastography is applied with the transducer directed toward the lung. Further studies are needed to determine the safety of this modality.
  相似文献   
993.
Oral squamous cell carcinoma (OSCC) has a very poor prognosis because of its highly invasive nature, and the 5‐year survival rate has not changed appreciably for the past 30 years. Although cylindromatosis (CYLD), a deubiquitinating enzyme, is thought to be a potent tumour suppressor, its biological and clinical significance in OSCC is largely unknown. This study aimed to clarify the roles of CYLD in OSCC progression. Our immunohistochemical analyses revealed significantly reduced CYLD expression in invasive areas in OSCC tissues, whereas CYLD expression was conserved in normal epithelium and carcinoma in situ. Furthermore, downregulation of CYLD by siRNA led to the acquisition of mesenchymal features and increased migratory and invasive properties in OSCC cells and HaCaT keratinocytes. It is interesting that CYLD knockdown promoted transforming growth factor‐β (TGF‐β) signalling by inducing stabilization of TGF‐β receptor I (ALK5) in a cell autonomous fashion. In addition, the response to exogenous TGF‐β stimulation was enhanced by CYLD downregulation. The invasive phenotypes induced by CYLD knockdown were completely blocked by an ALK5 inhibitor. In addition, lower expression of CYLD was significantly associated with the clinical features of deep invasion and poor overall survival, and also with increased phosphorylation of Smad3, which is an indicator of activation of TGF‐β signalling in invasive OSCC. These findings suggest that downregulation of CYLD promotes invasion with mesenchymal transition via ALK5 stabilization in OSCC cells. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
994.
The ultrasonographic (US) findings of 25 infant cases detected by the Japanese mass screening program for neuroblastoma (NB) were reviewed. The following results were obtained: An identification of the primary site was possible in 96% of the cases with abdominal US. An estimation of the tumor weight was possible based on the mass volume, which was calculated from US measurements. With the combination of the estimated mass volume, local involvement, and distant metastasis, the US grading of NB was possible and closely corresponded to the surgical staging (84%). The NB cases of adrenal origin at U1a, with a mass volume of less than 16 mL, were all found to be stage I and presented the possibility for spontaneous regression. © 1995 John Wiley & Sons, Inc.  相似文献   
995.
BACKGROUND: Magnetic resonance imaging is an accurate non-invasive tool for visualizing muscles, tendons, and bones. It also provides 3D coordinate values. The purpose of the present study was to visualize and quantify the 3D positions of the glenohumeral joint during isometric abduction of the arm using vertically open magnetic resonance imaging. METHODS: We examined 14 shoulders of seven healthy volunteers. Magnetic resonance images were obtained in a seated position and in seven static positions of the arm from 0 degrees to maximum abduction using vertically open magnetic resonance imaging. 3D surface models were created and 3D movements of each bone in the glenohumeral joint were calculated using a computer algorithm. We analyzed the translation and contact pattern of the glenohumeral joint. FINDINGS: In supero-inferior direction, the humeral head translated slight inferiorly from +1.9 (SD 1.0) mm at 0 degrees to +0.8 (SD 1.8) mm at the maximum abduction. In antero-posterior direction, the humeral head translated anteriorly from 0 degrees to 90 degrees (mean +2.4, SD 2.6 mm) and posteriorly from 90 degrees to 150 degrees of abduction (mean -1.4, SD 2.7 mm). Furthermore, the humeral head had a unique contact patterns with the glenoid; the contact part of the humeral head with the glenoid changed from the central part to the posterior in the midrange of abduction. INTERPRETATION: The humeral head showed a small translation in the antero-posterior direction between 90 degrees and 150 degrees of abduction. In addition, the posterior part of the humeral head contacted the glenoid in this range of abduction. These findings of motion patterns in asymptomatic subjects will be necessary when comparing the kinematics with pathologic condition such as the glenohumeral instability and rotator cuff tear.  相似文献   
996.
997.
Epithelioid glioblastomas are one of the rarest histological variants of glioblastomas, which are not formally recognized by the World Health Organization (WHO) classification. Epithelioid glioblastomas usually occur as primary lesions, but there have been several reports of secondary epithelioid glioblastomas or epithelioid glioblastomas with pre‐ or co‐existing lesions to date. The serine/threonine‐protein kinase B‐Raf (BRAF) V600E mutation has been found at a high frequency of 54% in epithelioid glioblastomas. We present a case of a 26‐year‐old female patient with an epithelioid glioblastoma with the BRAF V600E mutation in her right frontal lobe. In the present case, a low‐grade diffuse astrocytoma component had colocalized with the epithelioid glioblastoma. The component presented prominent calcification on neuroimages as well as by histology, and low‐grade diffuse astrocytoma was considered to be a precursor lesion of an epithelioid glioblastoma. However, the BRAF V600E mutation was detected only in epithelioid glioblastoma but not in low‐grade diffuse astrocytoma. To the best of our knowledge, this is the first report demonstrating a discrepancy in the BRAF V600E mutation states between epithelioid glioblastoma and colocalized low‐grade astrocytoma.  相似文献   
998.
Intercellular adhesion molecule-1 (ICAM-1) is involved in inflammation and development of atherosclerotic change of vascular endothelium. The aim of the present study is to investigate whether K469E polymorphism of the ICAM-1 gene is associated with various clinical factors including plasma fibrinogen in patients with type 2 diabetes. ICAM-1 gene polymorphism was examined using polymerase chain reaction and restriction enzyme analysis in 360 type 2 diabetic patients. Plasma fibrinogen levels and other clinical variables were measured as well as circulating soluble ICAM-1 (sICAM-1) levels by enzyme-linked immunosorbent assay. The distribution of ICAM-1 genotypes, EE, EK, and KK, was not significantly different between type 2 diabetes and 152 healthy control subjects. Among 3 groups according to ICAM-1 genotypes in type 2 diabetes, no difference was found in adiposity, glycemic control, lipid profile, insulin sensitivity evaluated by homeostasis model assessment, or sICAM-1. Regarding fibrinogen, the patients with E allele showed significantly lower plasma fibrinogen levels in a dose-dependent manner (P = .033). Spearman rank correlation analyses revealed that ICAM-1 genotype showed significant correlation with plasma fibrinogen level (P < .001). In multiple regression analysis, ICAM-1 genotype was independent contribution factor of plasma fibrinogen level as well as high-density lipoprotein-cholesterol and urinary albumin excretion (R2 = 0.148, P < .001). In conclusion, K469E polymorphism of the ICAM-1 gene had impact on plasma fibrinogen level independently of other clinical factors in 360 type 2 diabetic patients, suggesting that fibrinogen is a candidate which links the ICAM-1 gene polymorphism to atherosclerosis.  相似文献   
999.
1000.
In vivo efficacy of tosufloxacin (TFLX) for treatment ofChlamydia trachomatis cervical infection in women was evaluated by enzyme immunoassay. The short term (within 31 days of treatment) response rates with a dosage of 150 mg orally 3 times daily were 100% (54/54) with 14 days of treatment and 97% (38/39) with 7 days of treatment. Subjective symptoms such as lower abdominal pain, vaginal discharge, or atypical bleeding were observed in 76 (82%) of the 93 patients. After treatment, symptoms improved in 75 (99%) of 76 patients. Two of 34 patients (5.9%) showed positive results in the long interval tests (1 to 18 months after treatment). Three (2.3%) of 131 patients needed to be changed from TFLX to other drugs due to side effects (eczema, face edema, urticaria). TFLX was effective and patients showed high compliance for treatment of cervicalC. trachomatis infection.  相似文献   
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