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31.
A three-dimensional rigid body spring model (3D-RBSM) was used to analyse force distribution through the wrist joint. In the neutral position, 48% of the force was transmitted through the radioscaphoid fossa, 40% through the radiolunate fossa, and 12% through the triangular fibrocartilage complex. In the functional position, the wrist joint was slightly extended, resulting in significantly increased force through the lunate (53%). The lunate appears to bear more load than has been reported previously.  相似文献   
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PURPOSE: Transitional cell carcinoma (TCC) of the urinary tract is a chemosensitive tumor. Most deaths from TCC of the urinary tract are caused by metastasis, which is resistant to conventional chemotherapy. Frequent sites of metastases from TCC of the urinary tract are regional lymph nodes, liver, lung, and bone. Of these distant metastases, bone metastasis is consistently resistant to cisplatin-based conventional chemotherapy. Therefore, in this study, we investigated whether or not a newly developed minodronate, YM529, could prevent osteolytic bone metastasis of human TCC and also enhance the effect of docetaxel in a bone tumor model of athymic nude mice. EXPERIMENTAL DESIGN: In the present study, we evaluated the effect of in vitro treatment with minodronate and/or docetaxel on the proliferation by cell count, the induction of apoptosis by terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay, and the biological activity of osteoclast by pit formation assay in human bladder cancer cell line, UMUC-14, and mouse osteoclast cells. In vivo, we examined the effect of minodronate in a bone tumor model of athymic nude mice, in which the percutaneous intraosseal injection in the tibia of UMUC-14, leads to osteolytic bone tumor, as a bone metastasis model. To examine whether or not minodronate could inhibit tumorigenicity and enhance the effect of the chemotherapeutic agent, docetaxel, we gave minodronate i.p. and/or docetaxel i.p. to nude mice 3 days after an intraosseal tumor implantation. Moreover, proliferation and the induction of apoptosis of cancer cells and osteoclasts in bone tumors were determined by immunohistochemistry and the TUNEL assay. RESULTS: In vitro: In vitro treatment with docetaxel inhibited proliferation and resorption pit-forming activity and induced apoptosis of mouse osteoclast cells and UMUC-14 cells. In vitro treatment with minodronate inhibited proliferation and activity and induced apoptosis of mouse osteoclast cells but not UMUC-14 cells. The treatment with minodronate enhanced the inhibition of proliferation and activity by docetaxel in osteoclasts. In vivo: In vivo combination therapy with docetaxel and minodronate significantly reduced the tumor incidence compared with the control (P < 0.05) and also growth of intraossal TCC in athymic nude mice compared with the control (P < 0.001), single therapy with docetaxel (P < 0.01), and minodronate (P < 0.05). Drug-induced body weight loss was not significantly different in any treatment group. Therapy with minodronate significantly enhanced inhibition of proliferation by docetaxel in osteoclasts of bone tumors compared with the control (P < 0.01), single therapy with docetaxel (P < 0.01), and minodronate (P < 0.05). CONCLUSIONS: These studies indicate that combination therapy with minodronate and docetaxel may be beneficial in patients with bone metastasis of human TCC in the urinary tract.  相似文献   
35.
A young woman with microscopic polyangiitis (MPA) requiring hemodialysis showed repeated posterior reversible encephalopathy syndrome (PRES) with spatiotemporal multiple lesions over a period of two months. The first PRES episode with confusion and the second PRES episode with vertigo and nausea were caused by MPA, hypertension and renal failure. These symptoms were improved by the reinforcement of MPA treatment and blood pressure management. The third PRES episode with nausea, headache, seizure and visual changes was induced by rituximab infusion and hypertension. The PRES was improved with blood pressure and convulsant management. These conditions are challenging to diagnose and treat.  相似文献   
36.
We herein report two cases of potentially life-threatening arrhythmia due to hyperkalemia triggered by the excessive consumption of “Hoshi-Imo” (dried sweet potato). Both patients with chronic renal disease on renin-angiotensin-aldosterone system inhibitors presented at the emergency room with non-specific symptoms. Electrocardiograms revealed potentially life-threatening arrhythmia due to hyperkalemia in both cases: sinus arrest with a ventricular escape rhythm, tall and peaked T waves; and a widened QRS complex in a nearly sine-wave configuration without discernible P wave. Both patients fully recovered after intensive care for hyperkalemia. Physicians should recognize the excessive consumption of “Hoshi-Imo” may lead to the development of life-threatening arrhythmia, especially in patients with risk factors for hyperkalemia.  相似文献   
37.
Clinical trials have not fully demonstrated the efficacy and safety of radiotherapy plus cetuximab for locally advanced squamous cell head and neck cancer (LA-SCCHN) in patients with cisplatin-ineligible renal dysfunction. Patients who received radiotherapy plus cetuximab for LA-SCCHN at Chiba University Hospital (Chiba, Japan) between July 2013 and October 2018 were retrospectively reviewed. Background characteristics and locoregional control and overall survival rates were compared between patients with and without renal dysfunction. Survival was examined using Kaplan-Meier analysis and an adjusted Cox proportional hazards model. Kaplan-Meier analysis demonstrated that overall survival was shorter in patients with creatinine clearance of <45 ml/min (P=0.041; log-rank test). However, there was no difference in the locoregional control rate (P=0.477; log-rank test). Adjusted Cox analysis revealed that the risk of death was increased by 2.52-fold (hazard ratio, 2.52; 95% confidence interval, 1.01-6.30; P=0.048) if creatinine clearance was <45 ml/min. Moderate to severe renal dysfunction did not affect the locoregional control rate in patients with LA-SCCHN treated with radiotherapy plus cetuximab but was an adverse prognostic factor.  相似文献   
38.
Histopathological diagnosis is the ultimate method of attaining the final diagnosis; however, the observation range is limited to the two‐dimensional plane, and it requires thin slicing of the tissue, which limits diagnostic information. To seek solutions for these problems, we proposed a novel imaging‐based histopathological examination. We used the multiphoton excitation microscopy (MPM) technique to establish a method for visualizing unfixed/unstained human breast tissues. Under near‐infrared ray excitation, fresh human breast tissues emitted fluorescent signals with three major peaks, which enabled visualizing the breast tissue morphology without any fixation or dye staining. Our study using human breast tissue samples from 32 patients indicated that experienced pathologists can estimate normal or cancerous lesions using only these MPM images with a kappa coefficient of 1.0. Moreover, we developed an image classification algorithm with artificial intelligence that enabled us to automatically define cancer cells in small areas with a high sensitivity of ≥0.942. Taken together, label‐free MPM imaging is a promising method for the real‐time automatic diagnosis of breast cancer.  相似文献   
39.
Iodine-123 labelled iomazenil ([123I]IMZ) has been reported to be a useful marker of neuronal viability. The brain distribution of [123I]IMZ, however, has not been correlated with the pathophysiological response in detail after an ischaemic insult. To characterise [123I]IMZ as a marker of neuronal viability, we compared its brain distribution with cyclooxygenase-2 (COX-2) expression, DNA fragmentation and cellular integrity. [123I]IMZ and [125I]IMP were injected into rats with focal cerebral ischaemia for the purpose of dual-tracer autoradiography. COX-2 and microtubule-associated protein-2 (MAP-2, a marker of cellular integrity) were immunostained. In situ DNA polymerase-I-dependent dUTP incorporation into damaged DNA was used as an indicator of DNA fragmentation. Lesion to normal ratios (LNRs) for [123I]IMP and [125I]IMZ were calculated. [123I]IMZ accumulation was preserved in several regions with impaired [123I]IMP accumulation. COX-2 expression was occasionally observed, whereas neither DNA fragmentation nor MAP-2 denaturation was detected in these regions. DNA fragmentation and impaired MAP-2 immunostaining were observed only in the regions with reduced LNRs for both tracers. The LNR for [123I]IMZ was significantly lower in regions with impaired MAP-2 immunostaining (0.120±0.152, P<0.0001), in regions positive for dUTP incorporation (0.488±0.166, P<0.0001) and in regions positive for COX-2 expression (0.626±0.186, P<0.001) than in histologically normal regions (0.784±0.213). Thus, neuronal DNA is still intact and cellular integrity is maintained in the ischaemic regions with preserved [123I]IMZ accumulation. The impairment of [123I]IMZ accumulation precedes DNA fragmentation and denaturation of cellular integrity. These results provide the molecular basis of [123I]IMZ distribution.  相似文献   
40.
Correlation of CT and ultrasound in the evaluation of renal lymphoma   总被引:5,自引:0,他引:5  
In a series of 225 patients with lymphoma studied by computed tomography, involvement of the kidney(s) was found in 11 (4.9%). These cases were then also studied by ultrasound. Because of the characteristic findings of computed tomography and sonography in renal lymphoma, a reliable diagnosis was possible along with an accurate assessment of the incidence and types of renal involvement. Illustration of this material along with a discussion of the clinical implications of these findings is presented.  相似文献   
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