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61.
Neurosurgical Review - Although transvenous embolization (TVE) via the superior ophthalmic vein (SOV) is adopted in treating cavernous sinus dural arteriovenous fistula (CS DAVF), its effect on the... 相似文献
62.
Atsushi SAITO Takashi INOUE Shinsuke SUZUKI Masayuki EZURA Hiroshi UENOHARA Teiji TOMINAGA 《Neurologia medico-chirurgica》2021,61(3):228
Few studies have reviewed the roles of perfusion magnetic resonance (MR) imaging in the histopathological examination of meningiomas. We analyzed the relationships between radiological findings on perfusion MR imaging and pathological characteristics such as origin of the tumor, mitotic activity, pathological subtype, and perifocal edema formation. The subjects were 21 surgical cases of meningioma preoperatively evaluated by perfusion MR imaging. A region of interest (ROI) was set inside of the tumor, and perifocal edema of the same size, cerebral blood volume (CBV), and cerebral blood flow (CBF) on perfusion MR and diffusion-weighted (DW) imaging were analyzed. These radiological data were evaluated in comparison with histopathological characteristics. On perfusion MR imaging, the average ratio of CBV against the contralateral side was 6.43 (1.13–20.0) and that of CBF was 7.73 (1.34–11.3). There was no significant relationship with perfusion MR imaging data, tumor volume, or perifocal edema volume. However, the large peritumoral edema group often had a higher CBV and CBF than the non-large peritumoral edema group. The skull base group had a significantly higher CBV and lower signal intensity on DW images than the non-skull base group. Signal intensity on DW images was higher in grade II or III than in grade I. Perfusion MR imaging data revealed that the higher ratio of peritumoral edema against tumor size was associated with higher blood flow and blood volume under intratumoral circulatory conditions, and that skull base meningioma had a higher blood volume than non-skull base meningioma. 相似文献
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Jun Hatazawa Hiroshi Itoh Eku Shimosegawa Iwao Kanno Matsutaroh Murakami Shuichi Miura Hidehiro Iida Toshio Okudera Atsushi Inugami Toshihide Ogawa Hideaki Fujita Yuichi Satoh Ken Nagata Yutaka Hirata Kazuo Uemura 《Annals of nuclear medicine》1994,8(3):213-217
We studied the brain uptake of amino acid in a patient with acute cerebral infarction with L-[2-(F-18)] fluorophenylalanine and positron emission tomography. The increased accumulation of the ligand was specifically found in the peri-infarct area where oxygen metabolism was still maintained but decreased later in the 72-day follow-up period. The kinetic analysis revealed that increased accumulation was not due to increased transport from the blood to the brain but to delayed washout from the brain to the blood. Although the mechanism is still unknown, abnormally high accumulation of L-[F-18]fluorophenylalanine may predict delayed neuronal changes after ischemic insults of the brain. 相似文献
66.
To investigate cholecalciferol (vitamin D) metabolism disorders in hepatic osteodystrophy (HOD) and the effects of vitamin D, its metabolites, and calcium (Ca) on HOD, an experimental HOD model in rats was developed using carbon tetrachloride. In the serum level of 25-hydroxycholecalciferol, 1,25-dihydroxycholecalciferol, and 24R,25-dihydroxycholecalciferol, there were no significant differences between normal and control cirrhotic rats. Vitamin D supplementation significantly inhibited the atrophy of intestinal villi, reduction of bone calcium content, elevation of bone resorption, reduction of osteoid volume, and reduction of bone volume. Ca supplementation significantly increased the serum free Ca index and inhibited the elevation of bone resorption, the reduction of bone ash and Ca content, and the reduction of bone volume. This experimental study demonstrates that: (1) no marked vitamin D hydroxylation disorder was found in HOD; (2) vitamin D supplementation was effective in inhibiting HOD; and (3) sufficient Ca supplementation was also effective in inhibiting HOD.A portion of this work was presented at the 13th Annual Meeting of the Japanese Society for Bone and Mineral Research, July 1995, Fukuoka, Japan. 相似文献
67.
Kato M Imamura M Hosotani R Shimada Y Doi R Itami A Komoto I KosakaM T T Konishi J 《World journal of surgery》2000,24(11):1425-1430
The intravenous secretin injection test (secretin test) has been used for the differential diagnosis of gastrinoma. In this
study we report that the intraoperative secretin test (IOS test) is also useful for determining the extent of curability in
patients with Zollinger-Ellison syndrome (ZES). Twelve patients with ZES underwent surgical exploration and the IOS test.
The results of the IOS test were obtained by rapid radioimmunoassay of the serum gastrin level (IRG) within 60 minutes. The
test was diagnosed as negative when the maximum increase of serum IRG was less than 80 pg/ml and also less than 20% of the
basal serum IRG level. Three of the twelve patients underwent pancreatoduodenectomy (PD), and two patients underwent distal
pancreatectomy. Extirpation of duodenal tumors with dissection of regional lymph nodes was performed in seven patients. In
two of the seven patients the IOS test remained positive after extirpation of the duodenal tumors and the dissection of regional
lymph nodes. In one patient PD was performed on the basis of the positive results, and the IOS test became negative after
PD. In the other patient, two tiny metastatic liver tumors were identified and were resected, but the IOS test did not become
negative. We closed the abdomen in 11 patients when we obtained negative results from the IOS test. The results of the IOS
test were almost identical to the data obtained by the standard assay postoperatively. The serum IRG levels of all but one
patient fell to the normal level, and the secretin test became negative postoperatively. The IOS test is thus useful and indispensable
for curative resection of microgastrinomas in patients with ZES. 相似文献
68.
Regulation of p27 by S-phase kinase-associated protein 2 is associated with aggressiveness in non-small-cell lung cancer. 总被引:13,自引:0,他引:13
Atsushi Osoegawa Ichiro Yoshino Shinji Tanaka Kenji Sugio Toshifumi Kameyama Masafumi Yamaguchi Yoshihiko Maehara 《Journal of clinical oncology》2004,22(20):4165-4173
PURPOSE: The F-box protein S-phase kinase-associated protein 2 (Skp2) is one of the positive regulators of the cell cycle that promote ubiquitin-mediated proteolysis of the cyclin-dependent kinase inhibitor p27. In this study, we investigated the significance of Skp2 expression in human non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Clinicopathologic features and immunohistochemical expression of Skp2 and p27 proteins were studied in 138 patients with NSCLC. Survival analyses were performed using the Kaplan-Meier method and the Cox regression model. To analyze the role of Skp2 in vitro, NSCLC cells were transfected with an Skp2-expressing vector or small interfering RNA. RESULTS: Skp2 was overexpressed in males, smokers, patients with squamous cell carcinomas, and patients with poorly differentiated cancers (P = .034, < .0001, < .0001, and .002, respectively). The multivariant analysis revealed that Skp2 expression is an independent prognostic factor for survival in NSCLC. An inverse relationship of Skp2 with p27 expression was observed (P = .012), and patients with both a higher expression of Skp2 and a lower expression of p27 showed a significantly unfavorable prognosis (P = .0002). In vitro ectopic expression of Skp2 in NSCLC cells reduced the protein level of p27. Conversely, induction of Skp2 siRNA increased the protein level of p27, leading to growth inhibition in NSCLC cells. CONCLUSION: Skp2 overexpression is closely associated with the suppression of p27 and the aggressiveness in NSCLC. It also could be a therapeutic target in NSCLC. 相似文献
69.
70.
Atsushi Yoshida Takashi Sugiyama Tsutomu Tabata Toshiharu Okugawa Norimasa Sagawa 《The Ultrasound Review of Obstetrics & Gynecology》2006,6(3):109-114
The usefulness of the vascular ultrasound in the field of obstetrics is now well recognized. Intima-media thickness (IMT) and elastic property of the common carotid artery are affected by pregnancy and vary with complications. Flow-mediated vasodilation (FMD) of the brachial artery reflects the vascular endothelial function and is reported to be useful in the management of complicated pregnancy, especially pre-eclampsia. For the screening of deep vein thrombosis of the lower extremities in the perinatal period, compression ultrasonography (CUS) is useful. 相似文献