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81.
We report a case of primary epithelioid hemangioendothelioma arising in the liver. There were no specific findings or signs except for the deformity and multiple lesions of the liver at imaging procedures, which included magnetic resonance imaging. The key to the diagnosis was histological examination of liver biopsy specimens obtained under laparoscopy. Plasma factor VIII activity was elevated, which was also helpful in the diagnosis.  相似文献   
82.
Hepatocellular carcinoma (HCC) often develops in patients with chronic liver diseases associated with hepatitis B (HBV) and hepatitis C (HCV) virus infections with high incidences. Particularly, post-therapeutic recurrence encountered after the curative treatment of the preceding HCC may limit the prognosis. Thus, prevention of HCC is of great significance. In the present review, immunopreventions with alpha-interferon and glycyrrhizin, as well as chemoprevention with acyclic retinoid, are discussed. alpha-Interferon prevents the development of HCC not only in patients with a long-term elimination of HCV (sustained virological responders), but in ones with normalized serum aminotransferases (sustained biochemical responders). Glycyrrhizin also suppresses serum aminotransferases and thereby prevents the tumor development, even though the compound does not have antiviral activity for HBV or HCV by itself. Therefore, suppression of hepatic necroinflammation by these drugs may serve to prevent hepatocarcinogenesis. In contrast, acyclic retinoid suppresses the post-therapeutic recurrence in cirrhotic patients who underwent curative treatment of preceding tumors. The retinoid induces the disappearance of serum lectin-reactive alpha-fetoprotein (AFP-L3), a tumor marker indicating the presence of unrecognizable tumors in the remnant liver, suggesting a deletion of such minute (pre)malignant clones (clonal deletion). As a molecular mechanism of the clonal deletion, a novel mechanism of apoptosis induction by the retinoid via tissue transglutaminase is implicated. In future, a combination of immunopreventive and chemopreventive therapies may give a clue to the further advances of cancer prevention, and thereby to the improvement of the prognosis of cirrhotic patients.  相似文献   
83.

Introduction

When teaching dental radiology to undergraduate dental students, we should ideally cover all of the contemporary radiological fields evenly. However, it has become challenging to provide sufficient instruction within the curriculum compared with past times, because new radiological techniques quickly become popular. In the present study, we classified the questions received from sixth-grade students in Osaka Dental University for the purpose of better understanding the elements of effective teaching.

Materials and methods

We classified the questions received from sixth-grade students in Osaka Dental University using e-mail and the LINE mobile messaging app, from October 2011 to October 2014. The classification was based on the table of contents of Oral and Maxillofacial Radiology, Fifth Edition. In addition, we itemized the questions related to dental radiology set in national dental examinations performed from 2012 to 2015. We then compared the students’ concerns with the contents of the national examinations.

Results

Many questions were related to intraoral radiographic imaging, X-ray generation and projection geometry, radiographic interpretation, radiological protection, contrast-enhanced X-ray examination, panoramic imaging, and side effects of radiotherapy.

Conclusions

The reasons why students had difficulty in understanding specific areas were considered to be the compressed ratio of lecture time and contents, difficulty in giving full scope to the imagination, and lack of chances to observe equipment in clinical use.
  相似文献   
84.
We herein report the first case of foveolar-type gastric adenocarcinoma that developed after the initiation of vonoprazan (VPZ). A 51-year-old man had heartburn at the first visit and reflux esophagitis endoscopically, so he started taking VPZ. An approximately 5-mm-sized reddish polyp with a raspberry-like morphology was detected at the anterior wall of the upper body of the stomach 156 weeks after starting maintenance therapy with VPZ 10 mg/day. It was diagnosed as foveolar-type gastric adenocarcinoma based on a biopsy. Another approximately 4-mm-sized foveolar-type gastric adenocarcinoma was also detected at the posterior wall of the middle body of the stomach.  相似文献   
85.
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87.
The presence of immunoreactive xanthine oxidase protein was proven in a xanthinuric patient, using a polyclonal antibody against xanthine oxidase. The antibody was raised against purified human liver xanthine oxidase in a rabbit. Double immunodiffusion method demonstrated the existence of an immunologically reactive xanthine oxidase which did not possess xanthine oxidase activity. In addition, urinary excretion of oxypurines in the patient and her family was investigated. The results indicated that a brother and a sister had xanthinuria.  相似文献   
88.
89.
BACKGROUND: Uric acid is a strong scavenger of reactive oxygen species, which are known to contribute to the development of atherosclerosis, while the incidence of atherosclerotic diseases is rather high in patients with gout. Among the established risk factors for atherosclerosis, oxidized LDL is believed to play a major role in its development and progression. Allopurinol and its active metabolite, oxypurinol, have been suggested to possess an antioxidant ability to scavenge the hydroxyl radical. Therefore, allopurinol may be beneficial in the prevention of LDL oxidation, as well as in the treatment of hyperuricemia. The objective of this work was to determine the degree of LDL oxidation in gout and the effect of allopurinol on LDL oxidation. METHODS: Age-matched male patients with primary intercritical gout and healthy male adults were included in the study. The serum concentrations of oxidized LDL autoantibodies and total antioxidant status were measured using an enzyme immunoassay. RESULTS: Serum concentrations of oxidized LDL autoantibodies were significantly higher in patients with gout than the control subjects (p < 0.05) and were significantly decreased after allopurinol treatment (p < 0.05), but not by benzbromarone treatment, in spite of the similar concentrations of uric acid and total antioxidant status in serum following their separate administration. CONCLUSIONS: Although the exact mechanism remains unclear, increased serum concentrations of oxidized LDL may play a role in the high incidence of coronary artery disease in gout. In addition, allopurinol may be more preferable to benzbromarone for treatment of gout in light of its inhibitory action toward LDL oxidation.  相似文献   
90.
Twenty-three patients were studied to evaluate the clinical usefulness of high resolution B-mode ultrasonography in the detection of carotid lesions in patients with Takayasu's arteritis. In each patient the carotid arteries were examined using both B-mode ultrasonography (midfrequency of 7.5 MHz) and contrast angiography. In 19 of 23 patients, B-mode ultrasonography clearly demonstrated the characteristic circumferential arterial wall thickening of either one or both sides of the common carotid arteries as a macaroni-like, diffusely thickened intima-media complex. Conversely, contrast angiography demonstrated carotid lesions in only 13 of 23 patients. These results clearly show that B-mode ultrasonography is quite sensitive and superior in the detection of the characteristic thick intima-media complex of the common carotid artery in patients with Takayasu's arteritis, when compared with contrast angiography that is usually used for the definitive diagnosis of this disease.  相似文献   
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