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91.
OBJECTIVE: To determine the antitumor activity and toxicity of weekly hepatic arterial infusion (HAI) of 5-fluorouracil (5-FU) for liver metastases from colorectal cancer. In addition, the present study also evaluated the efficacy of second-line chemotherapy after termination of HAI. METHODS: A retrospective study was designed to evaluate the clinical outcome in patients treated with HAI. Twenty-six patients with liver metastases from colorectal cancer were treated with 5-FU 1000 mg/m(2) over 5 h once per week on an outpatient basis. The treatment was continued until disease progression, unacceptable toxicity or the patient's refusal to continue treatment occurred. One of three kinds of second-line systemic chemotherapy, irinotecan alone, protracted venous infusion of 5-FU or methotrexate (MTX) and 5-FU, was chosen after termination of HAI. RESULTS: An objective tumor response to HAI was observed in 46% (95% confidence interval, 26.9-65.2%) of 26 patients. The most common adverse events were mild nausea and vomiting (35%) and occurrence of gastroduodenal ulcers (15%). Hematological toxicity was minimal. No responder was observed to improve following second-line chemotherapy after termination of HAI. CONCLUSION: Weekly HAI of 5-FU is both active and well tolerated. However, extrahepatic progression was observed in one-third of patients with termination of HAI and the efficacy of second-line chemotherapy was not demonstrated. Regional treatment with systemic chemotherapy should be conducted to achieve good results in terms of survival.  相似文献   
92.
The present study was conducted to examine the effects of selective cyclooxygenase (COX)-2 inhibitors, nimesulide and etodolac, on early stages of tongue carcinogenesis due to 4-nitroquinoline 1-oxide(4-NQO). Fischer 344 rats, 6 weeks old, were given 15 ppm of 4-NQO in their drinking water for 8 weeks followed by diet containing either nimesulide or etodolac at the doses of 150 and 300 ppm for 16 weeks. Rats were sacrificed at 24 weeks and tongue lesions were histologically examined. Nimesulide dose-dependently reduced the incidence and multiplicity of squamous cell dysplasias and carcinomas (SCCs), with significance at the 300 ppm dose. This suppression was associated with an increased incidence and multiplicity of hyperplasias. Etodolac exhibited similar but less extensive suppressive effects. The results suggest that COX-2 is involved in the progression of hyperplasia to dysplasia and from dysplasia to SCCs.  相似文献   
93.
We have been developing a small, lightweight motor-driven pulsatile left ventricular assist device (LVAD) with a ball screw. The motor-driven LVAD consists of a brushless DC motor and a ball screw. The attractive magnetic force between Nd–Fe–B magnets (with a diameter of 5 mm and a thickness of 1.5 mm) mounted in holes in a silicone rubber sheet (thickness 2 mm) and an iron plate adhered onto the a diaphragm of the blood pump can provide optimum active blood filling during the pump filling phase. The LVAD has a stroke volume of 55 ml and an overall volume of 285 ml; it weighs 360 g. The controller mainly consists of a fuzzy logic position and velocity controller to apply doctors' and engineers' knowledge to control the LVAD. Each unit of the controller consists of a functionally independent program module for easy improvement of the controller's performance. The LVAD was evaluated in in vitro experiments using a mock circulation. A maximum pump outflow of 5.1 l/min was obtained at a drive rate of 95 bpm against an afterload of 95 mmHg, and active filling using the attractive magnetic force provided a pump output of 3.6 l/min at a drive rate of 75 bpm under a preload of 0 mmHg. The operating efficiency of the LVAD was measured at between 8% and 10.5%. While the LVAD can provide adequate pump outflow for cardiac assistance, further upgrading of the software and improvement of the blood pump are required to improve pump performance and efficiency.  相似文献   
94.
BACKGROUND: We previously reported elevated levels of total serum IgE in patients with asthma, regardless of their atopic status. We hypothesized that certain factors inherent to asthma may contribute to this non-specific elevation of total serum IgE. In the current study, to evaluate the role of eosinophils in the regulation of total serum IgE, we examined whether peripheral blood eosinophil count is associated with total serum IgE level in patients with eosinophilic lung diseases. METHODS: Ninety-nine healthy controls, 277 patients with asthma, 15 patients with acute eosinophilic pneumonia, 21 patients with chronic eosinophilic pneumonia were studied for total serum IgE levels and peripheral blood eosinophil counts. RESULTS: Patients with acute or chronic eosinophilic pneumonia had significantly increased total serum IgE levels compared with healthy controls regardless as atopic status (p<0.001). In non-atopic subjects with eosinophilic lung diseases, total serum IgE level was significantly correlated with peripheral blood eosinophil count (r=0.42, p<0.001, n=57). CONCLUSION: Our findings suggest that, in addition to antigen-specific IgE production, non-specific IgE production may contribute to elevated levels of total serum IgE in patients with asthma or eosinophilic pneumonia. An increased number of activated eosinophils may underlie an increased total serum IgE level in these conditions.  相似文献   
95.
Summary The reparative process following left ventriculotomy was investigated immunohistochemically using anti-type I, II, III, IV, V and VI collagen antibodies, and anti-fibronectin antibody. Wound healing began with proliferation of young fibroblasts positive for type I, III and V collagens at the wound margin; vascular granulation tissue then grew into the injured myocardium followed by deposition of fibrous components immunoreactive with type I and III. At 30 days after operation when almost the entire thickness of the myocardium at the wound was replaced by fibrosing granulation tissue, a small cluster of adipocytes appeared around capillaries at the wound margin. The granulation tissue was gradually replaced by the adipose tissue with establishment of a fibrous union at the subendocardium by 90 days. In addition to type I and III collagens, type VI collagen was detected in a fine fibrillary pattern along thick collagen fibre bundles in the fibrous tissue and around the adipocytes. Fibronectin was distributed diffusely in the granulation tissue and gradually decreased with increase of the fibrous components. These results indicate that the ventriculotomy was finally repaired in the form of a fibrous scar, particularly in the endocardium. There was marked infiltration of adipose tissue in the damaged myocardium. Presumably type VI collagen, as well as type I and type III collagens, plays an important role in wound union.  相似文献   
96.
Bare TiO2 photocatalyst almost quantitatively converted nitrobenzene to aniline with various saccharides without the use of hydrogen gas. Although aniline was formed when any saccharide was used, the use of disaccharides (lactose, maltose, and sucrose) decreased the reaction rate. The rate of photocatalytic hydrogenation of nitrobenzene using saccharides is determined by the degradation rate of saccharides at positive holes. When glucose was used, formic acid, arabinose, glyceraldehyde and lactic acid were obtained, which are products that are consistent with the product of the photocatalytic oxidation of glucose.

10 kinds of saccharides were investigated as hydrogen source in photocatalytic hydrogenation of nitrobenzene to aniline.  相似文献   
97.
A 75-year-old man was treated for 4 weeks with penicillin administration for infective endocarditis in the mitral valve caused by Enterococcus faecalis. The infection recurred, so he received penicillin administration for a further 6 weeks. He remained afebrile and all laboratory examinations were within normal limits for 6 weeks after the antibiotic treatment was discontinued, but the vegetation remained large and highly mobile. Since the onset, possible embolic episodes had occurred three times. He underwent mitral valve repair with annuloplasty. Although the infection appeared to have healed by antibiotic therapy, resected tissue was strongly positive for Enterococcus faecalis. This case suggests that surgery should be aggressively considered if the vegetation does not shrink markedly.  相似文献   
98.
OBJECTIVES: Some subjects infected by Helicobacter pylori have enlarged folds in the gastric body, the precise mechanism of which remains obscure. The aim of this study was to clarify the association of tumour necrosis factor-alpha (TNFA) gene polymorphism with susceptibility to hyper-rugosity. We also examined the association of TNFA polymorphism with gastric carcinoma. SUBJECTS AND METHODS: Four hundred and seventy-two subjects (male/female = 351/121, aged 26-81 years) without gastric carcinoma (control group), and 300 patients (male/female = 218/82, aged 32-91 years) with gastric carcinoma. Barium meal roentgenograms were performed in 396 subjects in the control group and fold width was measured at the greater curvature of the middle portion of the gastric body. Fasting plasma anti-H. pylori IgG titres, pepsinogens (PGs) I and II were analysed, and TNFA -857 promoter polymorphism was distinguished by the 5' nuclease polymerase chain reaction assay and polymerase chain reaction restriction fragment length polymorphism using HincII in both groups. RESULTS: Adjusted odds ratios of TNFA -857 T/T genotype and H. pylori seropositivity for hyper-rugosity (fold width = 6.0 mm) were 6.7 (95% confidence interval (CI) 1.5-28, P < 0.01) and 18.2 (95% CI 4.2-78, P < 0.0001), respectively. There were no significant differences in any genotype or allele frequencies between the control and total gastric carcinoma group. In a subgroup of gastric carcinoma patients who were negative for the PG assay, however, the odds ratio of the T allele was 1.4 (95% CI 1.0-2.0, P < 0.05). CONCLUSION: The TNFA -857 T/T genotype and H. pylori infection were strongly associated with rugal hyperplastic gastritis. The TNFA -857 T allele may promote gastric carcinoma without severe atrophy.  相似文献   
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