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11.
A Nishikawa F Furukawa M Mitsui T Enami T Kawanishi T Hasegawa M Takahashi 《Carcinogenesis》1992,13(7):1155-1158
The effects of calcium chloride on glandular stomach carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and sodium chloride were investigated in male outbred Wistar rats. Animals were given MNNG solution (100 p.p.m.) as drinking water and simultaneously fed a diet supplemented with 5% sodium chloride for 8 weeks. Matched negative controls received neither MNNG nor sodium chloride. Rats were then fed basal diet and given calcium chloride solution (1 or 0.2%) or tap water for the following 52 weeks. The incidences and multiplicities of preneoplastic hyperplasias in the glandular stomachs of rats given MNNG/sodium chloride followed by 1 and 0.2% calcium chloride were significantly lower than those in rats given MNNG/sodium chloride alone. The inhibitory effects of calcium were exerted in a dose-dependent manner. Calcium treatment also showed a tendency to inhibit the development of gastric adenocarcinomas although this was not statistically significant. Rats without carcinogen treatment had neither carcinomas nor preneoplastic hyperplasias in the glandular stomach. Calcium intake also significantly reduced the levels of malondialdehyde, a measure of lipid peroxidation, in the gastric mucosa and urine, the former in a dose-dependent manner. Thus, calcium chloride exerted inhibitory effects when given during the post-initiation phase of two-stage glandular stomach carcinogenesis in rats. 相似文献
12.
Hiroomi Murayama Masanobu Meda Ken Miyahara Yoshimasa Sakai Hajime Sakurai Hiroki Hasegawa Akemi Kawamura 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(3):91-97
Objective: We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery.
Methods: Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group
2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in
both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous
blood products. Results: No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5±3.4
mL/kg. Intraoperative donation was 21.7 ±6.1 mL/kg in Group 1 and 12.8±4.0 mL/kg in Group 2 (p<0.001). On admission, serum
hemoglobin was lower in Group 1 (12.2±1.0 g/dL versus 13.6±1.6 g/dL, p<0.001) but returned postoperatively to the preoperative
value. It hovered at a depressed level in Group 2 (12.2±1.4 versus 10.2±1.1 g/dL, p<0.001). The homologous blood requirement
was significantly less in Group 1 than in Group 2 (0% versus 10%, p<0.05). Postoperative platelet counts showed similar curves,
and blood loss was not statistically significantly different between groups. Conclusion: Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing
important options in comprehensive blood conservation programs in current pediatric open-heart surgery. 相似文献
13.
Kimie Sai Takashi Umemura Atsuya Takagi Ryuichi Hasegawa Yuji Kurokawa 《Cancer science》1992,83(1):45-51
The roles of glutathione (GSH), cysteine, vitamin C., liposome-encapsulated superoxide dismutase (L-SOD) and vitamin E in preventing oxidative DNA damage and cytotoxicity in the rat kidney after administration of potassium bromate (KBrO3 ) to male F344 rats were investigated by measuring 8-hydroxydeoxyguanosine (8-OH-dG), an oxidative DNA product, lipid peroxidation (LPO) levels and relative kidney weight (RKW). Combined pre- and posttreatment of animals with 2 × 800 mg/kg GSH i.p. inhibited the increase of 8-OH-dG, LPO levels and RKW caused by 80 mg/kg KBrO3 i.p. administration. In contrast, pretreatment with 0.3 ml/kg diethylmaleate (DEM) i.p., a depletor of tissue GSH, was associated with elevation of 8-OH-dG, LPO levels and RKW after a 20 mg/kg KBrO3 i.p. treatment, which itself caused no change. Administration of KBrO3 itself reduced renal non-protein thiol levels, but this was inhibited by the two doses of exogenous GSH. Combined treatment with DEM and KBrO3 lowered the non-protein thiol level in the kidney more than did DEM treatment alone. Protective effects against the oxidative damage caused by KBrO3 were also observed for pre- and posttreatment with 400 mg/kg cysteine i.p., another sulfhydryl compound, and daily i.g. application of 200 mg/kg vitamin C for 5 days. However, no influence was evident after pre- and posttreatment with 18,000 U/kg L-SOD i.p. or daily i.g. 100 mg/kg of vitamin E for 5 days. The results suggest that intracellular GSH plays an essential protective role against renal oxidative DNA damage and nephrotoxicity caused by KBrO3 . 相似文献
14.
Tsutomu Saito Hiroyuki Horimi Tsuguo Hasegawa Toshiro Kamoshida 《Surgery today》1993,23(12):1081-1084
We report herein the case of a 42-year-old man in whom dyspnea on exertion was found to be caused by isolated tricuspid stenosis. Two-dimensional echocardiogram showed thickening of the tricuspid valve with a markedly enlarged right atrium. A color-flow Doppler examination-revealed severe tricuspid stenosis without regurgitation and a Doppler-derived tricuspid diastolic pressure gradient of 23 mmHg. At the time of surgery, the patient was noted to have a stenotic tricuspid valve with thickened leaflets, fused commissures, and almost normal chorda tendineae. The valve leaflets were teased apart to the scattered specimen, and tricuspid valve replacement was successfully performed. Microscopic examination of the specimen demonstrated infective endocarditis. Isolated acquired tricuspid stenosis is extremely rare and, to our knowledge, this is the first case of infective endocarditis being involved as the primary cause. 相似文献
15.
Nine patients with small hepatocellular carcinomas, ranging up to 2 cm in size (phi: 1.7 +/- 0.2 cm, mean +/- SD), have been encountered, and in two of these patients the cancer was not identifiable by intraoperative ultrasonography. Thus to achieve a better detection of such small hepatic cancers, enhanced intraoperative ultrasonography was tested. Detection by enhanced intraoperative ultrasonography proved successful in all cases. These preliminary results indicate the potential of carbon dioxide as a contrast agent to enhance intraoperative visualization of small liver cancers. 相似文献
16.
Masanori Hisaoka Takatoshi Aoki Hiromi Kouho Hirofumi Chosa Hiroshi Hashimoto 《Skeletal radiology》1997,26(3):191-194
The case of a 49-year-old man with Maffucci’s syndrome, who developed multiple spindle cell hemangioendotheliomas, is presented.
The case provides support for recent reports suggesting an association between this peculiar vascular lesion and skeletal
enchondromatosis. 相似文献
17.
We report the case of a patient with delayed methotrexate (MTX)-induced leukoencephalopathy who showed a marked improvement both in clinical and neuroimaging findings after a high-dose of the active form of folinic acid (leucovorin) treatment. The patient developed progressive affective impairment accompanied by headache, nausea and vomiting after treatment with MTX during the chemotherapy for acute lymphoblastic leukemia, and diagnosed as delayed type MTX-induced leukoencephalopathy. After an intravenous injection of high-dose folinic acid (total 1920 mg), neurological deficits and white matter changes dramatically improved in a few weeks. Although delayed MTX-induced leukoencephalopathy may cause irreversible brain damage, an early treatment with high dose leucovorin may thus facilitate the marked improvement of clinical findings and white matter abnormalities. 相似文献
18.
Objective. To assess the diagnostic value of magnetic resonance imaging (MRI) as compared with radiographic findings in osteonecrosis in divers. Design and patients. MRI scans and conventional radiographs of the shoulder, hip and knee joints of 23 professional male scuba divers were reviewed together with their clinical findings and personal histories. Correlations between the MRI findings and the radiographic evaluation, clinical symptoms, and personal history were then investigated. Results and conclusions. Lesions found on MRI in 23 divers included 27 in 39 proximal humeri, 17 in 36 proximal femora, 13 in 32 distal femora, and 12 in 32 proximal tibiae. Diffuse, marginated, or irregular patterns were observed. No lesions were seen in epiphyses of the distal femur or proximal tibia. We tried to classify these MRI findings by location and appearance. MRI showed no patients with only one affected bone. A close correlation between the MRI findings and maximum diving depth was observed in the proximal humerus. MRI depicted bone lesions that could not be detected on the radiographs. A routine MRI investigation of the hip joints should be performed in every diver in whom osteonecrosis is diagnosed at another site, for early detection of femoral head osteonecrosis. MRI of the shoulder joint is also the best surveillance in divers who dive deeper than 15?m. 相似文献
19.
20.
The epidemiology and clinical features of anaphylactic and anaphylactoid reactions in the perioperative period in Japan] 总被引:3,自引:0,他引:3
H Mitsuhata S Matsumoto J Hasegawa 《Masui. The Japanese journal of anesthesiology》1992,41(10):1664-1669
In an attempt to review the Japanese epidemiology of the anaphylactic and/or anaphylactoid reactions in the perioperative period, we investigated 105 cases with clinical features of anaphylactic and/or anaphylactoid reaction, which are reported in the Japanese anesthesiology-related journals from 1952 to 1990. Eighty-nine percent of the cases were reported during the last decade. There were 66 males and 34 females. The majority of the patients were below 60 years of age, and most of the patients were in their teens and fifties. Ninety percent of the patients had no past history of drug-induced allergy nor tendencies of atopy. Ninety-four percent of the patients recovered completely without any sequelae, and 0.95 percent of them recovered with serious complications. Deaths occurred in 4.67% of the patients. Most frequent clinical signs were cardiovascular (91.4%) and cutaneous (84.8%) manifestations. Respiratory, signs appeared in 41% of the patients. Patients are frequently unconscious and covered with drapes, and early signs and symptoms of anaphylaxis can be masked. In 25% of the patients cardiovascular collapse, including cardiac arrest and undetected blood pressure, appeared as the first noticeable sign. Causative drugs were confirmed immunologically in 5.7% of the patients. In other cases, causative drugs were presumed based on clinical course. Causative drugs and presumed causative drugs were varied, including blood and blood products (24 cases), intravenous anesthetics (19 cases), local anesthetics (15 cases), and muscle relaxants (9 cases), which were used generally in the perioperative period. 相似文献