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991.
K Sayama T Higaki H Ohtsuka Y Kobayashi Y Shirakata S Shiraishi Y Miki 《The Journal of dermatology》1991,18(5):286-290
A case of diffuse neonatal hemangiomatosis is described. At birth, a giant tumor, 10 cm in diameter and 6 cm in height, was present on the left axilla and associated with thrombocytopenia. Numerous cherry-red papules were present on the skin and buccal mucosa. On the second day of life, the giant tumor was excised. Histological examination of the tissue revealed masses of endothelial cells embedded in fibrous tissues. Plain and enhanced computed tomography of the brain revealed a hemorrhage and two hemangiomas. The associations of intravascular papillary endothelial hyperplasia were discussed. 相似文献
992.
A New Experimental Model for Drug Studies: Effects of Phenobarbital and Phenytoin on Photosensitivity in the Lateral Geniculate-Kindled Cat 总被引:1,自引:0,他引:1
Yuji Wada Hiroshi Okuda Kazunori Yoshida Hidehiro Hasegawa Itsuki Jibiki Hideki Kido Nariyoshi Yamaguchi 《Epilepsia》1987,28(6):667-672
Photosensitivity was acquired as a result of kindling in the lateral geniculate body (GL), and the GL-kindled cat pretreated with DL-allylglycine showed a stable level of photosensitivity. To test the usefulness as a model for the evaluation of anticonvulsant drugs, the effects of phenobarbital (PB) and phenytoin (PHT) on photosensitivity were studied in the GL-kindled cat under DL-allylglycine. PB (5 and 10 mg/kg intravenously, i.v.) completely suppressed photically induced seizures in most subjects at plasma concentrations of 7-16 micrograms/ml, and this anticonvulsant action persisted for at least 4 h after the injection. PHT (15 mg/kg, i.v.) at plasma concentrations of 9-15 micrograms/ml produced toxic signs, e.g., pupil dilatation, hypersalivation, and tachypnea. At this dose, PHT was inactive against photically induced myoclonus but prevented the elicitation of a generalized tonic-clonic convulsion. From these results showing that the effects of anticonvulsant drugs on photically induced seizures can be assessed in relation to plasma concentration and acute neurologic toxicity, we suggest that the GL-kindled cat is a potentially useful animal model of epilepsy for testing the efficacy of anticonvulsant drugs. 相似文献
993.
Takayuki Omata Kazuhiro Saito Fumio Kotake Yuji Mizokami Takeshi Matsuoka Kimihiko Abe 《Magnetic resonance in medical sciences》2002,1(2):65-71
PURPOSE: Dynamic MR cholangiography was conducted on patients with cholelithiasis or choledocholithiasis who had consumed a fatty test meal (Molyork) and the cystic contractility and dynamics of biliary stasis was evaluated. SUBJECTS AND METHOD: The subjects were 25 with intracystic cholelithiasis, 10 with choledocholithiasis and 10 normal controls. For an imaging sequence, the rapid acquisition with relaxation enhancement (RARE) method was employed and imaging was conducted for 40 min (every 30 s following Molyork administration) without breath-holding. The gallbladder contraction ratio was computed and the contractile ratio for the common bile duct was calculated. To determine the bile flow to the duodenum, the high-intensity signal, indicating the flow from the lower common bile duct, and perfusion of the duodenum were observed in dynamic mode on the monitor with the naked eye and interpreted as positive bile flow. The frequency of this flow was visually monitored. RESULTS: The gallbladder contractile ratio was significantly reduced in patients with cholelithiasis or choledocholithiasis compared with the controls. In a comparison with the normal controls, no sequential changes were noted in the mean contractile ratio of the common bile duct of the patients with cholelithiasis or choledocholithiasis. The mean frequency of bile flow observed for each 40 min period was 13+/-2.4, 6+/-2.2, and 4+/-1.3 times for the controls, those with intracystic cholelithiasis, and those with choledocholithiasis, respectively. Compared with the controls, the latter two patient groups showed evident reductions in the frequency of bile flow to the duodenum (p<0.001). CONCLUSION: Dynamic MRC combined with Molyork loading makes it possible to compute cystic contractile ratios and perform a dynamic examination of bile flow under non-invasive, near-physiological conditions. 相似文献
994.
Yuji Ishii Toshiya Okamura Tomoki Inoue Masako Tasaki Takashi Umemura Akiyoshi Nishikawa 《Toxicology》2009,263(2-3):93-99
We have shown that direct reaction of catechol with nitric oxide (NO) results in generation of reactive oxygen and nitrogen species (RNS) through semiquinone radical formation, leading to oxidative DNA damage in rat forestomach. In the present study, we investigated whether dietary catechol systemically exerts the same effects under NO-rich circumstances, when given before and during induction of inflammatory lesions. Male ICR mice were treated with or without 0.8% catechol in the diet for 2 weeks followed by acetaminophen (APAP) administration at a dose of 300 mg/kg by single i.p. injection. Along with several indicators of APAP-induced hepatitis, 8-hydroxydeoxyguanosine (8-OHdG) levels and immunohistochemistry for 3-nitrotyrosine (NO2Tyr) in the livers were examined at 1.5, 4 and 24 h after APAP injection. 8-OHdG was significantly increased at 24 h in the co-treatment group, but not with either catechol or APAP alone. Elevation of serum ALT and AST activities, decrease of reduced glutathione levels and histopathological liver changes were observed to the same extents in both APAP-treated groups. In view of the finding of positive hepatocytes for NO2Tyr prior to generation of 8-OHdG, the process of oxidative DNA damage might involve RNS formation. Precise quantitative analysis of NO2Tyr by means of liquid chromatography with tandem mass spectrometry (LC-MS/MS) in an additional study with the same experimental protocol confirmed increase of RNS due to the reaction of catechol with NO produced after APAP-induced hepatitis. The overall data imply that antioxidants with a catechol structure can cause oxidative DNA damage under inflammatory conditions. 相似文献
995.
Kazuhiro Saito Tsuyoshi Hashimoto Fumio Kotake Hiroshi Nakamura Yuji Mizokami Koichi Shimokobe Kimihiko Abe 《Magnetic resonance in medical sciences》2002,1(4):199-205
PURPOSE: A study was conducted to determine the possibility of evaluating the blood flow in cases of hypervascular hepatocellular carcinoma (HCC) by employing dynamic MRI with superparamagnetic iron oxide (SH U 555 A), which can be rapidly injected via an intravenous route. METHODS: Six patients with hypervascular HCC (23 nodules) served as the subjects. Dynamic MRI includes images obtained at precontrast and at 10 (perfusion phase), 60, 120, 180, 240, 300 and 600 s after the start of injection of SH U 555 A. CT hepatic arteriography (CTHA) and CT during arterial portography (CTAP) were used as the standards of reference, and these were performed in all patients three days after dynamic MRI. The signal changes were evaluated at each phase, especially at the perfusion phase from the viewpoints of a lesion-to-liver contrast-to-noise ratio (CNR) and visual examination. RESULTS: A total of 23 hypervascular HCC were detected on CTHA and CTAP. Of the 23 lesions, 17 were detected on SH U 555 A enhanced MRI. Incorrect timing during acquisition of the perfusion phase was considered in two cases with three lesions. Of 14 lesions, excluding two cases with incorrect timing, a reduction in the transient signal in the lesions at the perfusion phase was visually recognized in 10 lesions (71%). Significant differences were seen in tumor size between visible and non-visible tumors involving transient signal reduction (p< 0.05). CNR gradually increased after rapidly decreasing in the perfusion phase. CONCLUSION: SH U 555 A enhanced MRI is valuable in limited cases. Evaluation of tumor blood flow employing dynamic MRI with SH U 555 A is affected by tumor size and requires optimal timing of the perfusion phase. 相似文献
996.
Masataka Kikuyama Yuji Matsubayashi Fujito Kageyama Shinichi Sumiyoshi Yoshimasa Kobayashi 《Digestive endoscopy》2005,17(1):9-12
Background: Endoscopic retrograde cholangiopancreatography (ERCP) and associated procedures have been reported to be difficult to perform in patients with Billroth II gastrectomy. We evaluated the feasibility of using an oblique‐viewing endoscope equipped with a cannula deflector for these procedures in such patients. Patients and Methods: Twenty‐four patients with Billroth II gastrectomy were enrolled in the present study and underwent ERCP, endoscopic sphincterotomy, endoscopic nasobiliary drainage, expandable metal stent placement or tube stent placement. All procedures were performed with an oblique‐viewing endoscope equipped with a cannula deflector. Results: In all patients, afferent loops were entered. Reaching the papilla of Vater was achieved in 22 (91.7%) patients, in whom all planned procedures were accomplished. One patient experienced acute pancreatitis, hemorrhage from the papilla of Vater after sphincterotomy, and intestinal perforation. Conclusions: We believe an oblique‐viewing endoscope equipped with a cannula deflector to be useful in performing ERCP and associated procedures in many patients with Billroth II gastrectomy. However, one should be aware of major complications, such as perforation, that may occur. 相似文献
997.
Ken-ichi Takahashi Yuji Funayama Kouhei Fukushima Chikashi Shibata Hitoshi Ogawa Iwao Sasaki 《Surgery today》2009,39(12):1080-1082
A 34-year-old woman presented with severe abdominal pain 8 years after undergoing ileal J-pouch anal anastomosis for ulcerative
colitis (UC). Computed tomography (CT) showed free air and ascites in the abdomen, so she underwent laparotomy. A perforation
was found at the ileal J-pouch blind end, which was remarkably enlarged. When we resected the blind end surgically, we observed
a 3-mm perforation and some small ulcers. About 2 months after this operation, the patient complained of abdominal pain and
an increased frequency of bowel movements. Based on our endoscopic observation of multiple ulcers, we diagnosed pouchitis.
We report this case to show that the combination of an enlarged J-pouch blind end and pouchitis can result in perforation.
To prevent such complications, we recommend avoiding the formation of a blind end during construction of a J-pouch. 相似文献
998.
Masato Momiyama Kenji Wakai Koji Oda Junichi Kamiya Yoshiyuki Ohno Michinari Hamaguchi Yasuni Nakanuma Ling-Ling Hsieh Ta-Sen Yeh Tse-Ching Chen Yi-Yi Jan Miin-Fu Chen Yuji Nimura 《Journal of gastroenterology and hepatology》2008,23(7PT1):1075-1081
Background and Aim: To examine associations between lifestyle risk factors and intrahepatic stone (IHS), we conducted a case–control study in Taiwan, which has the highest incidence of IHS in the world.
Methods: Study subjects were 151 patients newly diagnosed with IHS at Chang Gung Memorial Hospital between January 1999 and December 2001. Two control subjects per case were selected randomly from patients who underwent minor surgery at the same hospital and from family members or neighbors of the hospital staff. Controls were matched to each case by age and gender. Information on lifestyle factors was collected using a self-administered questionnaire. Strength of associations was assessed using odds ratios derived from conditional logistic models.
Results: Female patients were significantly shorter than female controls. Compared to subjects with two or fewer children, odds ratios for those with six or more children were 20.4 in men (95% confidence interval, 1.89–221) and 2.82 (0.97–8.22) in women. Increasing level of education lowered the risk of intrahepatic stone (trend P = 0.004 for men and < 0.0001 for women). Women who had consumed ground-surface water for a long period had a somewhat increased risk (trend P = 0.05).
Conclusion: Lower socioeconomic status and poor hygiene may be involved in the development of intrahepatic stones. 相似文献
Methods: Study subjects were 151 patients newly diagnosed with IHS at Chang Gung Memorial Hospital between January 1999 and December 2001. Two control subjects per case were selected randomly from patients who underwent minor surgery at the same hospital and from family members or neighbors of the hospital staff. Controls were matched to each case by age and gender. Information on lifestyle factors was collected using a self-administered questionnaire. Strength of associations was assessed using odds ratios derived from conditional logistic models.
Results: Female patients were significantly shorter than female controls. Compared to subjects with two or fewer children, odds ratios for those with six or more children were 20.4 in men (95% confidence interval, 1.89–221) and 2.82 (0.97–8.22) in women. Increasing level of education lowered the risk of intrahepatic stone (trend P = 0.004 for men and < 0.0001 for women). Women who had consumed ground-surface water for a long period had a somewhat increased risk (trend P = 0.05).
Conclusion: Lower socioeconomic status and poor hygiene may be involved in the development of intrahepatic stones. 相似文献
999.
Yuji Baba Yasuyuki Yamashita Mitsukazu Onomichi 《Magnetic resonance in medical sciences》2002,1(1):32-37
Dynamic MRI has been used to improve the detection of tumors and to make differential diagnosis. Most malignant lesions show early enhancement and early washout of contrast media on dynamic MRI, but the characterization of the tumor remains unclear. Pharmacokinetic analysis of dynamic MRI can provide information about the permeability of contrast media in the tumor that may reflect the oxygen concentration of the tumor. This information may be useful in the prediction of a tumor's response to radiation therapy. 相似文献
1000.