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11.
Sadao Ii Hiroyuki Tsuchiya Koutaro Takazawa Hiroshi Minato Katsuro Tomita 《Journal of orthopaedic science》2004,9(2):152-156
Adamantinoma is a rare low-grade malignant bone tumor with an indolent course. The tibia is involved in 85%–90% of long-bone cases. We encountered a patient with primary adamantinoma of the proximal femur. A 60-year-old woman fell and fractured her proximal left femur in the area of a cystic lesion. She underwent an osteosynthesis procedure, and bone union was obtained. After 3 years she developed pain in the left thigh, and a radiographic abnormality was found at the fracture site. A metastatic bone tumor was suspected, and curettage and cementing were carried out. Histologically, we found an epithelial component but failed to detect any primary cancer. Local recurrence became evident after another 6 years. A marginal excision was performed and a bipolar femoral prosthesis was implanted. We finally diagnosed the patient with adamantinoma. In this report we describe the characteristics of this tumor and discuss the reasoning concerning the differential diagnosis and therapeutic plan. 相似文献
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Effects of calmodulin antagonists on calcium-activated potassium channels in pregnant rat myometrium. 总被引:2,自引:1,他引:1 下载免费PDF全文
1. The effects of W-7, trifluoperazine, and W-5 on Ca2(+)-activated K(+)-channels were investigated with the inside-out patch-clamp method in smooth muscle cells freshly dispersed from pregnant rat myometrium. These drugs are known to have different potencies as calmodulin antagonists. 2. In the presence of 1 microM Ca2+ on the cytoplasmic side ([Ca2+]i), the fraction of time the channel was open (open probability, Po) was about 0.9 and the calmodulin antagonists (1-30 microM) applied to the cytoplasmic face reduced Po to 0.65-0.55 dose-dependently. In the presence of 0.1-0.16 microM Ca2+, when Po was very low (0.02), calmodulin antagonists increased Po. All antagonists used produced almost identical effects at the same concentration. 3. The probability density function of the open time distribution could be described by the sum of two exponentials. W-7 decreased the time constant of slow component of distribution and at 30 microM the slow component disappeared both at 1 and 0.25 microM [Ca2+]i, reflecting the appearance of flickering channel activity. The probability density function of the closed time distribution could be fitted with three exponentials. The time constants of these components were not significantly altered by W-7. 4. Internally applied calmodulin (1-5 microM) did not produce any significant effect on channel activity. 5. The effects of calmodulin antagonists are considered to be due to a direct action of these compounds on the channel, and suggest that channel activation by Ca2+ is not mediated by calmodulin. 相似文献
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Peripheral gangrene associated with Kawasaki disease. 总被引:3,自引:0,他引:3
Three American infants with Kawasaki disease (KD) complicated by peripheral extremity gangrene are reported. Eight such patients (only 1 from Japan) have been reported previously. These 11 patients, infants less than 7 months old at onset of KD, are predominantly non-Asian. At least nine had associated giant coronary aneurysms, and eight had associated peripheral arterial aneurysms. In eight infants the diagnosis of KD was not established and therapy was not instituted until greater than or equal to 14 days after onset. Peripheral ischemia initially was noted 15-31 days after onset. Although the pathogenesis of this complication is not well understood, it likely includes some combination of local peripheral arteritis, arteriospasm, thrombosis peripherally and/or more proximally (e.g., in an axillary artery aneurysm), and cardiogenic shock. Treatment may include use of antiinflammatory agents such as salicylates and intravenous gamma globulin, vasodilative agents and/or methods, and thrombolytic and/or anticoagulant agents in an attempt to prevent the potentially devastating consequences of progressive gangrene. 相似文献
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Akihiko Usui Fumihiko Murakami Hideki Ooshima Yasuhiro Tomita Katsuhiko Yoshida Michiaki Hibi Mitsuo Kawamura Mitsuya Muras 《Artificial organs》1997,21(7):772-778
Abstract: Cardiopulmonary support (CPS) requires durability of the oxygenator. The life span of the oxygenator is affected by various clinical factors, including patient condition, perfusion condition, and equipment usage. Predictors for the durability of oxygenators were evaluated clinically in this study. Thirty-two patients, who had undergone CPS during the last 3 years in our institute were assigned to this study. Fifty oxygenators had been used (Capiox SX in 19, CB Maxima in 23, and AL-6000 in 8). Significant predictors for the durability of oxygenators were evaluated by nonparametric survival analysis and proportional hazards regression analysis. Univariate regression analysis revealed 6 significant predictors for the life span of oxygenators. These were the oxygenator type, type of centrifugal pump, acidosis with blood pH less than 7.35, base excess less than -5, blood glutamic-oxaloacetic transaminase (GOT) levels greater than 1,000 IU, and blood lactate dehydrogenase (LDH) levels greater than 3,000 IU. After multivariate analysis, there remained only 2 significant predictors. An oxygenator used with a noncoated CPS system (Capiox SX with Capiox EBS) proved to have a significantly shorter life span than one used with a heparin-coated system (CB Maxima or AL-6000 with CB BP-80) (hazards ratio, 3.588, p = 0.0065). Patient conditions, which revealed acidosis with less than -5 of base excess, significantly shortened the life of the oxygenator (hazards ratio, 3.595, p = 0.0188). 相似文献
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Yoshihiro Handa MD Naoki Yamanaka MD Hiroshi Inagaki MD Yasushi Tomita MD 《Dermatologic surgery》2003,29(7):790-792
BACKGROUND: Hidradenoma papilliferum is an uncommon benign tumor that is located almost exclusively in the vulvar and anal areas. It is usually very small and asymptomatic, and to make a correct diagnosis is clinically very difficult. Occasionally the tumor becomes elevated to form a reddish brown papillary mass, and the surface ulcerates, which may erroneously suggest malignancy. OBJECTIVE: We report a case of a large, perianal hidradenoma papilliferum with suspected malignancy in a young Japanese female. RESULTS: A 22-year-old female had been aware of a perianal nodule for approximately 1 year. Examination of the perianal area revealed a wide pedunculated, reddish nodule with several white maculae. It was ulcerated and bleeding, 2.0 x 1.2 x 0.8 cm in size, and located in the 3 o'clock position. The nodule was totally excised with a narrow margin. The histopathologic diagnosis was hidradenoma papilliferum. No recurrence was observed for 23 months. CONCLUSION: When dermatologists encounter tumors of the anogenital area of adult females, it is important to keep hidradenoma papilliferum in mind as the differential diagnosis. Dermatologists should recognize that the tumor is benign, eliminating the need for wide resection. 相似文献
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Flufenamic acid (FA) is a widely used non-steroidal anti-inflammatory drug. It is also known to be an uncoupling agent of oxidative phosphorylation in mitochondria. The interaction of FA and ethanol has been of concern in the occupational health field, since alcohol consumption is a common habit among members of the working population. Thus, we investigated the effects of FA on ethanol metabolism in the rat. In the first experiment, FA and ethanol were administered intragastrically to male Wistar rats. Ethanol and acetaldehyde were measured in blood samples collected from the tail vein by head-space gas chromatography. In the second experiment, the interaction of FA and ethanol was observed in the perfused rat liver. The following items were monitored in perfused livers from both fed and fastd rats: uptake rate of ethanol, production rate of acetaldehyde, level of reduced pyridine nucleotides, and oxygen consumption rate. In the first experiment, the rats with FA showed significantly higher concentrations of both ethanol and acetaldehyde in blood after ethanol intake than the rats without FA. In the perfused liver, FA suppressed ethanol uptake, and increased acetaldehyde concentration in the effluent. FA decreased the level of intracellular reduced pyridine nucleotides which had been elevated by ethanol. FA caused an increase in the oxygen consumption rate, which was not altered by the coexistence of ethanol. It was concluded that FA suppressed ethanol metabolism due to suppression of acetaldehyde oxidation in the liver, despite its uncoupling effect on oxidative phosphorylation in mitochondria. 相似文献