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991.
Hirota S Fukuda T Matsumoto S Sugimoto K Isaki K Yoshikawa T Akasaka Y Sugimura K 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》2000,60(7):361-367
We reviewed the current techniques and published results of balloon-occluded retrograde transvenous obliteration (B-RTO) for gastric varices (GV) and hepatic encephalopathy. The portal hemodynamics of gastric varices were classified into three types according to their feeding vessels, and the development of collateral veins under balloon occlusion of gastro-renal shunt was classified into five grades. The main draining veins of gastric varices were gastro-renal and gastro-inferior phrenic shunts. Preprocedural diagnosis of portal hemodynamics is important in selecting the technique for B-RTO. The rate of disappearance or marked reduction of GV was 98%, and the rate of recurrence of GV was 2%. Hepatic encephalopathy due to gastro-renal shunt improved markedly. In contrast, esophageal varices were aggravated at rates of 10% to 62.5% by the post-procedural elevation of portal pressure. Common adverse effects were hemoglobinuria, abdominal pain, and low-grade fever, but ascites and pleural effusion were also reported. Severe complications such as cardiogenic shock, atrial fibrillation, and pulmonary embolism were reported. We await technical improvements and further indications for this procedure. 相似文献
992.
Shiraishi J Katsuragawa S Ikezoe J Matsumoto T Kobayashi T Komatsu K Matsui M Fujita H Kodera Y Doi K 《AJR. American journal of roentgenology》2000,174(1):71-74
OBJECTIVE: We developed a digital image database (www.macnet.or.jp/jsrt2/cdrom_nodules.html ) of 247 chest radiographs with and without a lung nodule. The aim of this study was to investigate the characteristics of image databases for potential use in various digital image research projects. Radiologists' detection of solitary pulmonary nodules included in the database was evaluated using a receiver operating characteristic (ROC) analysis. MATERIALS AND METHODS: One hundred and fifty-four conventional chest radiographs with a lung nodule and 93 radiographs without a nodule were selected from 14 medical centers and were digitized by a laser digitizer with a 2048 x 2048 matrix size (0.175-mm pixels) and a 12-bit gray scale. Lung nodule images were classified into five groups according to the degrees of subtlety shown. The observations of 20 participating radiologists were subjected to ROC analysis for detecting solitary pulmonary nodules. Experimental results (areas under the curve, Az) obtained from observer studies were used for characterization of five groups of lung nodules with different degrees of subtlety. RESULTS: ROC analysis showed that the database included a wide range of various nodules yielding Az values from 0.574 to 0.991 for the five categories of cases for different degrees of subtlety. CONCLUSION: This database can be useful for many purposes, including research, education, quality assurance, and other demonstrations. 相似文献
993.
994.
MGMT和Ki-67在胶质母细胞瘤中的表达对ACNU化疗预后的影响 总被引:2,自引:0,他引:2
背景与目的:胶质母细胞瘤是预后极差的常见颅内恶性肿瘤,手术切除、放疗和化疗联合应用是常规治疗方法;Ki-67是肿瘤细胞生长活跃程度的标志,与胶质瘤的分级显著相关;O6-甲基鸟嘌呤DNA甲基转移酶(MGMT)是一种DNA修复蛋白,其表达影响肿瘤对化疗药的敏感性。本研究通过免疫组织化学方法对胶质母细胞瘤的Ki-67和MGMT进行检测,探讨其对胶质母细胞瘤化疗预后的影响。方法:总结39例脑胶质母细胞瘤患者的性别、年龄、术前Karnofsky评分、生存时间等;将患者手术切除标本石蜡切片进行Ki-67和MGMT的免疫组织化学染色,计算细胞核染色阳性率;多元逐步回归分析法判断Ki-67和MGMT的表达与患者生存时间的关系。结果:本组病例男22例,女17例;年龄21~75岁,平均54.0岁;生存时间6~38个月,平均19.3个月,中位生存期17.0个月。Ki-67在所有标本有不同程度的表达,表现为胞核明显染色,Ki-67阳性率4.0%~26.6%,平均10.5%。MGMT除2例外均有不同程度表达,胞浆染色较淡,胞核可见浓染,MGMT胞核阳性率0%~51.4%,平均21.2%。Ki-67阳性率与生存时间无相关性。MGMT胞核阳性率与生存时间呈负相关(P=0.002)。结论:Ki-67在胶质母细胞瘤表达与肿瘤的预后无关。MGMT在胶质母细胞瘤表达与肿瘤化疗后的预后有关,MGMT的检测对胶质母细胞瘤术后化疗可能有指导意义。 相似文献
995.
Matsumoto S Nakajima S Nakamura K Etani Y Hirai H Shimizu N Yokoyama H Kobayashi Y Tajiri H Shima M Okada S 《Pediatric nephrology (Berlin, Germany)》2000,15(3-4):271-273
We report on a 10-year-old girl with glomerulonephritis associated with hepatitis C virus infection, who was treated with
interferon-α. On the first renal biopsy at 8 years of age, mild mesangial hypercellularity in a segmental to semiglobal pattern
was present in all glomeruli. After 6 months interferon-α therapy, proteinuria diminished completely. However, mesangial proliferation
was advanced on the second biopsy at 10 years of age. We concluded that the interferon-α was effective in the treatment of
proteinuria despite the lack of pathological improvement.
Received: 15 March 2000 / Revised: 11 July 2000 / Accepted: 14 July 2000 相似文献
996.
Yamaguchi T Yokokawa M Suzuki M Higashide S Katoh Y Sugiyama S Misaki T 《Surgery today》2000,30(12):1093-1099
This study was conducted to investigate whether systemic immunosuppression attenuated aortic dilatation in a rat aneurysm
model. Sprague-Dawley rats were subjected to elastase infusion of the infrarenal aorta and divided into two groups of 12 rats
each. The immunosuppression group (group 1) was given subcutaneous injections of cyclosporine A (5 mg/kg per day), azathioprine
(2 mg/kg per day), and methylprednisolone (2 mg/kg per day) from the operative day until postoperative day (POD) 6. An additional
subcutaneus injection of cyclophosphamide 30 mg/kg was also given on the operative day. The control group (group 2) was given
subcutaneous injections of saline. Relaparotomy was performed on POD 7. After measurement of the aortic diameter, aortography
and ultrasonography were performed in three rats from each group, following which the aortas were excised for histologic examination.
The aortic diameter was significantly smaller in group 1 (2.58 ± 0.37 mm) than in group 2 (6.21 ± 1.74 mm) (P < 0.01) and the aortic lumen was slightly dilated in group 1, whereas it was spherically dilated in group 2. Total loss of
elastic tissue was seen in both groups. Inflammatory cell infiltration and collagen fiber fragmentation were noted in group
2, whereas very little inflammatory cell infiltration and well-preserved collagen fibers were seen in group 1. These findings
showed that immunosuppression attenuates aortic dilatation, partly by preserving the collagen fibers, in this rat aneurysm
model.
Received: September 13, 1999 / Accepted: July 25, 2000 相似文献
997.
Hepatic resection using the harmonic scalpel 总被引:8,自引:0,他引:8
Sugo H Mikami Y Matsumoto F Tsumura H Watanabe Y Kojima K Futagawa S 《Surgery today》2000,30(10):959-962
We describe herein our technique of performing extensive resection of the liver by blunt dissection in combination with excision
using a harmonic scalpel. A ball coagulator was inserted at 3-cm intervals along the proposed cutting line in the liver, and
the liver parenchyma between these holes was then cut using coagulation shears. Regardless of the condition of the liver,
good coagulation and cutting were achieved using the harmonic scalpel without vascular occlusion when dividing the shallow
layer of the liver, and no complications in association with the harmonic scalpel, such as postoperative bleeding, bile leakage,
or abscess formation at the cut margins, occurred. In the deep layer below the main trunk of the hepatic vein, blunt dissection
was used, since it was difficult to achieve sufficient control of bleeding from large vessels using the harmonic scalpel alone.
Therefore, when used in combination with other techniques, the harmonic scalpel appears to be an effective device for liver
surgery that minimizes bleeding and decreases the vascular clamping time.
Received: October 14, 1999 / Accepted: May 30, 2000 相似文献
998.
Matsumoto T Takeya M Takuwa S Hiquchi E Fujimatsu A Maeshiro H Ito Y Kanno K Sasaki S Kato H 《Pediatric nephrology (Berlin, Germany)》2000,14(1):48-52
We observed severe overhydration in an 18-month-old Japanese girl with primary polydipsia. The secretion of antidiuretic hormone
(ADH) was decreased, and urinary excretion of aquaporin-2, a vasopressin-sensitive water channel protein, was suppressed under
basal conditions, but the response of aquaporin-2 to ADH was essentially preserved. These findings suggest that the water
channel itself was intact and that overhydration resulting from polydipsia was responsible for the decreased ADH secretion
and suppression of the water channel protein.
Received: 4 October 1996 / Revised: 23 February 1999 / Accepted: 23 February 1999 相似文献
999.
Fujikawa K Kobayashi T Sasazaki Y Matsumoto H Seedhom BB 《Journal of long-term effects of medical implants》2000,10(4):225-238
The Leeds-Keio (L-K) artificial ligament, developed for knee ligament reconstruction, is made of polyester with a maximum tensile strength of 2200 N. This implant works not only as a ligament but also as a scaffold onto which natural tissue grows from synovium. In an animal experiment, each strand of the L-K ligament was covered with new tissue by 2-3 weeks after anterior cruciate ligament reconstruction. Eight weeks postoperatively, abundant fibrous tissue with extensive vascularity covered the implant, which was still histologically immature. After 16 weeks, vascularization and tissue induction began to subside, and histologic analysis showed dense fibers running longitudinally and parallel. By 36 weeks, the new ligament looked like a natural anterior cruciate ligament, although histologically more cells could be seen than in the natural ligament. This maturation was observed only when the substitute was implanted under good tension. Clinically, the surgical procedure has been improved over the past 10 years, to the current practice in which the tape-in-tube double L-K ligament employs a small piece of autogenous tissue to promote early tissue induction and maturation. Using this practice (n = 135), more than 85% of the patients were satisfied subjectively, objectively, and arthroscopically at the 5-year postoperative FU period. Few patients had joint effusion postoperatively. Sacrifice of autogenous tissue is minimal. The patient can return to activities of daily living within 2 weeks, and more than 50% of them to sports within 10 weeks, and the new ligament is expected to keep its function for a long period as ingrowth completes the structure biologically. 相似文献
1000.
Hiroshi Matsumoto Yukio Koibuchi Jun Horiguchi Yuichi Iino Yasuo Morishita 《Oncology reports》2002,9(1):145-151
The efficacy of luteining hormone-releasing hormone (LH-RH) analogue, buserelin, combind with tamoxifen (TAM) on 7,12-dimethylbenz(a)anthracene (DMBA)-induced rat mammary tumors was investigated. Low-dose of TAM (L-TAM), 1 mg/kg daily, significantly suppressed the growth of tumors compared with no treatment group. High-dose of TAM (H-TAM), 10 mg/kg daily, suppressed growth considerably, and there was a significant difference in the antitumor effect between the L-TAM group and the H-TAM group. The combined treatment using buserelin and L-TAM significantly suppressed the tumor growth compared with the treatment using each single agent. LH-RH analogue actually reduced serum estradiol (E2) levels and enhanced the antitumor effect brought by a therapeutical dose of TAM. The reduction of serum cholesterol levels as a beneficial effect of TAM was reserved when combined with buserelin. Insulin-like growth factor 1 (IGF-1) expressions in tumors were significantly decreased in the buserelin and L-TAM group. These results support the usefulness of this combination in clinical use. 相似文献