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Sixty-one consecutive patients with multiple myeloma were studied with magnetic resonance (MR) imaging of the spine. Sagittal T1-weighted and short inversion time (TI) inversion recovery (STIR) images were obtained. The MR patterns of the bone marrow were classified as diffuse (D) ( n  = 26), nodular (N) ( n  = 11), D + N ( n  = 13) or normal (n) ( n  = 11). Abnormal patterns were seen in 50 (82%) of the 61 patients. Correlations were found between the MR imaging patterns and some laboratory findings (WBC, haematocrit, platelet count, serum albumin, and percentage of marrow plasmacytosis). The survival of the patients with abnormal MRI patterns was significantly poorer than that of the patients with normal patterns. However, the survival of patients with a nodular pattern did not differ from those with a normal pattern. The MR imaging pattern of the bone marrow in patients with multiple myeloma is a useful factor in the assessment of prognosis.  相似文献   
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A 75-year old man was referred to hospital for symptomatic hypoxemia. He did not complain of dyspnea while supine, but while sitting or standing, he experienced dyspnea with severe hypoxemia. He did not have any pulmonary diseases that could cause dyspnea. Transesophageal echocardiography revealed an atrial septal aneurysm with a small atrial septal defect (ASD) and a mild left-to-right shunt through the ASD when the patient was supine. However, when he became upright, a severe right-to-left shunt occurred and the arterial oxygen saturation decreased from 96% to 80% with dyspnea. Cardiac catheterization revealed normal pulmonary artery pressure. He was therefore diagnosed as having platypnea - orthodeoxia syndrome. Magnetic resonance imaging of the chest showed a deformity of the atrium associated with elongation of the ascending aorta. The ASD was closed surgically and the dyspnea and hypoxemia that occurred while he was upright completely resolved.  相似文献   
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ABSTRACT

Health risks attributed to low-frequency noise (LFN) exposure are a serious global issue. Therefore, the development of a method for a prevention based upon risk assessments for LFN is important. Previously in vivo exposure of mice to LFN at 100 Hz, 95 dB for 1 hr produced imbalance with breakage of the otoconial membrane, which covers hair cells as well as impaired activity of hair cells in the vestibule. However, methods for inhibition of LFN-mediated imbalance have not been developed. At present, there are no apparent techniques available with in vitro or ex vivo assessments to evaluate LFN-mediated imbalance by direct administration of preventive chemicals into the vestibule. Our findings demonstrated the usefulness of an explant culture of the utricle with a fluorescent styryl dye, FM1-43FX. In addition, examination of the morphology of the otoconial membrane with explant cultures of utricles was conducted to determine the risk of LFN. Ex vivo exposure of the utricle to LFN at 100 Hz, 95 dB for 1 hr induced breaks in the otoconial membrane as well as decreased uptake of FM1-43FX in hair cells. Taken together, the results of this study provide a novel technique for assessing the risk of LFN exposure using an ex vivo experiment.  相似文献   
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We report two cases of squamous cell carcinoma of the esophagus following endoscopic injection sclerotherapy for esophageal varices. The interval between sclerotherapy and the development of carcinoma was 24 months in case 1 and 21 months in case 2. The sclerosant was 5% sodium morrhuate in case 1 (total dose, 10 ml) and 5% ethanolamine oleate in case 2 (45.5 ml). Although no recurrent variceal bleeding occurred after sclerotherapy, we could not perform any curative surgical treatment for esophageal cancer because of the advanced stage of the cancer and the severity of the accompanying liver dysfunction. It is difficult to determine the relationship between sclerotherapy and carcinoma; however, long-term surveillance is essential to avoid overlooking a neoplasm in the esophagus after endoscopic injection sclerotherapy.  相似文献   
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This study examined the effect of synthetic porcine neuropeptide Y on the splanchnic blood flows and the exocrine pancreatic secretion in dogs. Graded doses of neuropeptide Y (0.1–5 g/kg, intravenous) caused dose-dependent reduction of the secretin-stimulated exocrine pancreatic secretion and of the blood flows in the superior mesenteric artery, the portal vein, and the pancreatic tissue. Neuropeptide Y at 5 g/kg reduced the blood flows to 45.9±13.3% (superior mesenteric artery), 63.0±10.5% (portal vein), and 77.9±4.8% (pancreatic tissue), respectively. This dose also reduced secretin-stimulated pancreatic juice volume and CCK-8 plus secretin-stimulated protein output to 65.2±9.3 and 63.3±14.0%, respectively. This study shows a potent vasoconstrictor effect of neuropeptide Y on splanchnic vessels. Neuropeptide Y also inhibited exocrine pancreatic secretion in a significant correlation with the reduction in pancreatic tissue blood flow, which suggests that reduction in the blood flow may be one of the possible mechanisms of the inhibitory action of neuropeptide Y on exocrine secretion.This work was supported by a grant from the Ministry of Education, Japan (A-61440060).  相似文献   
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背景幽门螺杆菌(H.pylori)感染已被确认为慢性胃炎的主要病因,由慢性非萎缩性胃炎、慢性萎缩性胃炎至肠化生,经过数十年最终可能导致胃癌发生。目的评价H.pylori感染与胃镜检查正常者、慢性胃炎、早期胃癌和进展期胃癌患者胃黏膜组织学特点的关系。方法在受检者胃窦大弯侧、胃体大弯侧和胃角处各取一块黏膜活检标本,以Giemsa染色和免疫组化染色检测H.pylori感染情况;以HE染色评价胃黏膜炎症、活动性、萎缩和肠化生情况。结果慢性胃炎、早期胃癌和进展期胃癌患者的总体H.pylori感染率均显著高于胃镜检查正常者(52.4%、52.4%和81.2%对44.9%,P<0.05),慢性胃炎与早期胃癌患者的感染率无显著差异,但均显著低于进展期胃癌患者(P<0.05)。胃镜检查正常和慢性胃炎组H.pylori感染者的胃黏膜炎症、活动性、萎缩和肠化生检出率均显著高于无感染者(P<0.05);早期胃癌和进展期胃癌组H.pylori感染者的炎症活动性检出率显著高于无感染者(P<0.05),而炎症、萎缩和肠化生检出率与无感染者无显著差异。结论由H.pylori感染引起的胃黏膜慢性炎症、萎缩和肠化生可能在胃癌的发生、发展过程中起直接或间接作用。  相似文献   
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