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101.
Neoadjuvant chemotherapy and radiation for inoperable carcinoma of the maxillary antrum: a matched-control study 总被引:2,自引:0,他引:2
Kim GE Chang SK Lee SW Pyo HR Choi EC Roh JK Keum KC Lee CG Suh CO 《American journal of clinical oncology》2000,23(3):301-308
A matched-control study comparing standard radiotherapy versus neoadjuvant chemotherapy and radiation was undertaken to clarify the effects of neoadjuvant systemic chemotherapy for locally advanced squamous cell carcinoma of the maxillary antrum. Thirty-four patients with inoperable maxillary cancer were treated with neoadjuvant chemotherapy and radiotherapy (Group II). Before starting radiotherapy, all patients in Group II received two or three cycles of neoadjuvant chemotherapy consisting of cisplatin and a 5-day continuous infusion of 5-fluorouracil with or without intravenous injection of vinblastine. Radiation doses ranged from 66 Gy to 75 Gy (median, 70 Gy). The response rate, patterns of failure, toxicity, and survival for Group II were compared with those for 34 stage-matched patients treated with radiation alone (Group I). Despite a higher response rate to neoadjuvant chemotherapy, the recurrence rate and patterns of treatment failure were not influenced by the addition of neoadjuvant chemotherapy. In most cases, neoadjuvant chemotherapy did not interfere with subsequent radiotherapy, and radiation-induced late complications occurred equally in both treatment groups. After a median follow-up of 48 months, there was no significant difference in 5-year actuarial survival or disease-free survival between the two treatment groups. Radiation alone for inoperable maxillary cancer was clearly suboptimal for improving local control and survival rate, but neoadjuvant chemotherapy in addition to standard radiotherapy failed to demonstrate any therapeutic advantage over radiation alone. 相似文献
102.
Combined effects of the orally active cisplatin analog, JM216, and radiation in antitumor therapy 总被引:1,自引:0,他引:1
Amorino GP Mohr PJ Hercules SK Pyo H Choy H 《Cancer chemotherapy and pharmacology》2000,46(5):423-426
Purpose: We evaluated the orally administered platinum agent, JM216, in combination with ionizing radiation both in vivo and in vitro
against human tumor cells. Methods: H460 human lung carcinoma cells were used as a subcutaneous xenograft in nude mice. JM216 (30 mg/kg) was administered orally,
and radiation treatments (2 Gy) were given 1 h after JM216 delivery for five consecutive days. For in vitro analysis, attached
H460 cells were treated with JM216 (15 μM) for 1 h and then irradiated. Cells were rinsed 20 min later, and survival was determined by clonogenic assay. Results: Tumor growth delay measurements showed that the combination of JM216 and radiation was additive in vivo, with an enhancement
ratio of 1.24. In vitro clonogenic survival experiments demonstrated a dose enhancement ratio of 1.23. Isobologram analysis
showed that this interaction was also additive. Conclusions: These data demonstrate that the combination of JM216 and fractionated radiotherapy is more effective against human lung
cancer xenografts than either agent alone, and the in vivo results were supported by those observed using an in vitro system
with the same tumor cell line.
Received: 20 December 1999 / Accepted: 24 May 2000 相似文献
103.
R Bahl N Bhandari MK Bhan M Saxena A Bagati 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(11):1290-1294
Objectives : To determine the efficacy of antimicrobial treatment in non-dysenteric persistent diarrhoea in a community setting. Methods : In this double-blind field trial, 156 children aged 4 36 months with persistent diarrhoea not associated with Giardia lamblia infestation seeking treatment in a community outpatient clinic, were randomized to receive a combination of nalidixic acid and metronidazole, metronidazole alone, or placebo for 7 days. Results : In comparison with placebo, metronidazole treatment did not result in a significant reduction in the mean post-enrolment diarrhoeal duration and stool frequency, increase in the proportion of patients recovered by days 3, 5 and 7 of treatment, and increase in weight gain at days 7 and 14. Comparing the combination of nalidixic acid and metronidazole with metronidazole alone, 17.5% more children treated with the combination recovered by day 3 of treatment ( p = 0.08) and the mean stool frequency ascertained on day 7 for the previous 24 h was 26.8% less in them ( p = 0.05). The weight gains at days 7 and 14 were similar in the two groups. Conclusions : These findings indicate that metronidazole offers no therapeutic benefit in persistent diarrhoea not associated with Giardia lamblia and nalidixic acid has only a modest clinical benefit, which is not substantial enough to warrant its routine use. 相似文献
104.
Yeong Shik Kim Mi Kyung Pyo Kyung Mi Park Bum Soo Hahn Kyung Youl Yang Hye Sook Yun-Choi 《Archives of pharmacal research》1998,21(4):374-377
The freeze-dried powder ofLumbricus rubellus earthworm was administered orally to rats and its fibrinolytic and antithrombotic effects were investigated. The fibrinolytic
activity of plasma was determined by measuring the plasmin activity of the euglobulin fraction and was increased to two-folds
of the control at a dose of 0.5g/kg/day and five times with 1 g/kg/day after 4-day administration. The antithrombotic effect
was studied in an arterio-venous shunt model of rats. The thrombus weight decreased significantly from 43.2 mg to 32.4 mg
at a dose of 0.5g/kg/day after 8-day treatment. The level of fibrinogen/fibrin degradation product (FDP) in serum was elevated
in a dose-dependent manner during the treatment period. On the 8th day after administration, the FDP value was increased to
7.7 μg/ml compared with the control value of 3.3 μg/ml. These results support that earthworm powder is valuable for the prevention
and/or treatment of thrombotic conditions. 相似文献
105.
Background
Haemorrhage after Cardio Pulmonary Bypass (CPB) Surgery is a well recognised complication that leads to significant morbidity and mortality. The incidence varies between 5-25% depending upon the clinical situation. Several factors are implicated as causative but none have been precisely proved.Methods
Our study was an attempt to evaluate the haemostatic defect with particular reference to platelet function abnormalities during cardio pulmonary bypass surgery, in order to reduce the morbidity and mortality associated with post CPB haemorrhage. Flow cytometric evaluation of different platelet glycoproteins like GPIb/IX, GPIIb/IIIa and GMP-140 was done.Results
The marker expression showed deregulation during surgery which returned to base after bypass was terminated. In contrast, the cases with bleeding showed significant variation. P-Selectin (GMP 140) expression decreased progressively till 3rd post-operative day showing lack of activation of platelets in cases of severe bleeding.Conclusion
Longer duration of CPB initiates plasmin generation through heparin, which raises the PAI-1-tPA complex and thereby down regulating the functions of platelets. This suggests a link between duration of CPB, bleeding, platelet dysfunction and fibrinolysis. Hence serial estimations of the levels of GMP-140 and tPA can predict severe bleeding.Key Words: CardioPulmonary Bypass, Platelet dysfunction, flowcytometry, platelet glycoproteins, haemorrhage 相似文献106.
Synthesis and inhibition of PGE2 production of 6,8-disubstituted chrysin derivatives 总被引:1,自引:0,他引:1
A series of 6,8-disubstituted chrysin derivatives have been synthesized and evaluated for their PGE2 inhibitory activities. 6,8-Disubstituted chrysin derivatives were obtained from naturally occurring chrysin by halogenation, oxidation, thiomethylation and C-C cross coupling reaction. Among the compounds investigated, 6,8-dibromochrysin (2), 6,8-diiodochrysin (4), 6,8-dimethylthiochrysin (9) and 6,8-dimethoxychrysin (11) showed as strong inhibitory activities of PGE2 production from LPS-induced RAW 264.7 cells as wogonin, a well known natural flavone having strong and selective COX-2 inhibitory activity. 相似文献
107.
Modulation of chondrocytic properties of fat-derived mesenchymal cells in co-cultures with nucleus pulposus 总被引:3,自引:0,他引:3
Human subcutaneous fat-derived mesenchymal cells recently have been shown to have the potential to differentiate in vitro into a variety of cell types, including adipocytes, osteoblasts, chondrocytes, and myoblasts. This effect suggests that fat tissue may serve as an abundant and easily acquired source of multipotent cells for tissue engineering. The multipotential characteristics of fat-derived mesenchymal cells from the inguinial fat pad of rabbit have not been clearly defined. In this study we have isolated a population of mesenchymal cells from inguinal fat from adult New Zealand white rabbits. The cells that were maintained under various differentiation conditions were shown to differentiate in vitro into adipocytes, osteoblasts, or chondrocytes; this differentiation was demonstrated using gene expression for tissue-specific proteins. We also co-cultured the cells with intervertebral disk tissue from the nucleus pulpous or from the annulus fibrosus. The fat-derived cells co-cultured with nucleus pulposus showed an increase in expression of type II collagen and aggrecan genes, compared with cells in alginate alone and cells co-cultured with annulus fibrosus. The data suggest that the fat-derived mesenchymal cells responded to soluble mediators from the disk. Future studies on intervertebral disk reconstruction could be based on our findings with fat-derived multipotential cells from the inguinal region of the rabbit that were co-cultured with disk tissue and may prove useful in tissue engineering strategies. 相似文献
108.
Lee SY Lee JW Lee H Yoo HS Yun YP Oh KW Ha TY Hong JT 《Brain research. Molecular brain research》2005,140(1-2):45-54
Beta-amyloid peptide (Abeta) is considered responsible for the pathogenesis of Alzheimer's disease (AD). Several lines of evidence support that Abeta-induced cytotoxicity is mediated through the generation of reactive oxygen species (ROS). Thus, agents that scavenge ROS level may usefully impede the development or progress of AD. Green tea extract has been known to have such antioxidant properties. Our previous studies demonstrate that green tea extract protected ischemia/reperfusion-induced brain cell death by scavenging oxidative damages of macromolecules. In this study, we investigated the effects of green tea extract on Abeta-induced oxidative cell death in cultured rat pheochromocytoma (PC12) cells. PC12 cells treated with Abeta25-35 (10-50 microM) showed intracellular ROS elevation, the formation of 8-oxodG (an oxidized form of DNA), and underwent apoptotic cell death in a dose-dependent manner. Abeta(25-35) treatment upregulated pro-apoptotic p53 at the gene level, and Bax and caspase-3 at the protein level, but downregulated anti-apoptotic Bcl-2 protein. Interestingly, co-treated green tea extract (10-50 microg/ml) dose-dependently attenuated Abeta(25-35) (50 microM)-induced cell death, intracellular ROS levels, and 8-oxodG formation, in addition to p53, Bax, and caspase-3 expression, but upregulated Bcl-2. Furthermore, green tea extract prevented the Abeta(25-35)-induced activations of the NF-kappaB and ERK and p38 MAP kinase pathways. Our study suggests that green tea extract may usefully prevent or retard the development and progression of AD. 相似文献
109.
110.