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71.
目的上皮-间充质化(epithelial-mesenchymal transition,EMT)是实体瘤原发灶癌细胞获得转移能力的基础。缺氧诱导前列腺癌、肾癌、卵巢癌的EMT过程已得到证实,缺氧诱导因子1α(hypoxia inducible factor 1 alpha,HIF-1α)在这些过程中发挥重要作用。但是HIF-1α和肝癌细胞EMT之间的关系目前并不清楚。本文探讨HIF-1α在肝癌EMT中的作用。方法利用可调控HIF-1α表达的肝癌HepG2Tet-on-HIF-1α细胞系,在排除缺氧其他反应干扰的情况下研究HIF-1α在肝癌细胞EMT过程中的作用和机制。结果过表达HIF-1α促进HepG2肝癌细胞EMT,下调HIF-1α表达可以抑制HepG2肝癌细胞EMT。HIF-1α促进EMT相关转录因子Snail的表达。结论 HIF-1α通过上调Snail来促进HepG2肝癌细胞EMT。 相似文献
72.
Tamoxifen and its analogues 4-hydroxytamoxifen, toremifene, 4-
hydroxytoremifene, clomifene and droloxifene were tested for clastogenic
effects in a human lymphoblastoid cell line (MCL-5) expressing elevated
native CYP1A1 and containing transfected CYP1A2, CYP2A6, CYP2E1 and CYP3A4
and epoxide hydrolase and in a cell line containing only the viral vector
(Ho1). MCL-5 or Ho1 cells were incubated with 4-hydroxytamoxifen,
4-hydroxytoremifene, clomifene or droloxifene and the incidence of
micronuclei estimated. With MCL-5 cells there was an increase in
micronuclei with 4-hydroxytamoxifen, 4- hydroxytoremifene and clomifene but
not with droloxifene. With Ho1 cells only 4-hydroxytamoxifen and
4-hydroxytoremifene caused an increase in micronuclei. MCL-5 cells were
incubated with tamoxifen, 4- hydroxytamoxifen, toremifene, droloxifene,
clomifene or diethylstilbestrol (0.25-10 microg/ml) for 48 h and subjected
to 3 h treatment with vinblastine (0.25 microg/ml) to arrest cells in
metaphase. The incidence of cells with chromosomal numerical aberrations
(aneuploidy) was increased in cells treated with tamoxifen,
4-hydroxytamoxifen, toremifene, clomifene and diethylstilbestrol but not
droloxifene. The frequency of cells with structural abnormalities
(excluding gaps) was increased in cells treated with tamoxifen and
toremifene but not 4-hydroxytamoxifen, clomifene, droloxifene or
diethylstilbestrol. The clastogenic activities of tamoxifen (35 mg/kg),
toremifene (36.3 mg/kg), droloxifene (35.2 mg/kg) and diethylstilbestrol
(25 mg/kg) were compared in groups of four female Wistar rats. Each
chemical was dissolved in glycerol formal, administered as a single dose by
gavage and hepatocytes isolated by collagenase perfusion 24 h later. The
cells were cultured in the presence of epidermal growth factor (40 ng/ml)
for 48 h, colchicine (10 microg/ml) being added for the final 3 h of
incubation. At least 100 chromosomal spreads were examined from each animal
for the presence of numerical and structural abnormalities. The incidences
of aneuploidy following treatment were: tamoxifen 81%, toremifene 46%,
droloxifene 9.6%, diethylstilbestrol 45.7%, vehicle control 5.3%. The
incidences of chromosomal structural abnormalities excluding gaps were:
tamoxifen 4.3%, toremifene 0.8%, droloxifene 0.5%, diethylstilbestrol 0.8%,
control 0.5%. The incidence of chromosomal structural aberrations excluding
gaps in the treated animals was not statistically significantly different
from controls except in the tamoxifen-treated group. Tamoxifen (35 mg/kg
per os) and toremifene (36.3 mg/kg per os) were dosed to rats for 4 weeks
and chromosomal spreads made from hepatocytes. The incidences of aneuploidy
were: tamoxifen 94%, toremifene 57%, control 6.5%. The incidences of
chromosomal aberrations excluding gaps were: tamoxifen 12%, toremifene 1%,
control 0.5%. The incidence of tamoxifen-induced chromosomal structural
abnormalities was significantly elevated compared with control levels. The
results demonstrate that tamoxifen and toremifene are the only two drugs
tested in the study that cause chromosomal structural and numerical
aberrations in vitro and tamoxifen is the only drug that induces both these
effects in rat liver cells stimulated to divide in culture following oral
dosing. Since chromosomal mutations require cell division for their
manifestation and tamoxifen is the only compound of those tested that
causes hyperplasia in the rat liver, chromosomal aberrations and aneuploidy
in the rat liver would only be expected to occur following treatment with
tamoxifen alone, although aneuploidy could be induced by toremifene in
conjunction with a promoter such as phenobarbitone.
相似文献
73.
74.
T Chen L Jansen A Gondos K Emrich B Holleczek S Luttmann A Waldmann H Brenner;THE GEKID CANCER SURVIVAL WORKING GROUP* 《Acta oncologica (Stockholm, Sweden)》2012,51(7):915-921
Abstract Purpose. Population-based studies on cervical cancer providing survival estimates by age, histology, and stage have been sparse. We aimed to derive most up-to-date and detailed survival estimates for cervical cancer patients in Germany. Methods. We used a pooled German national dataset including data from 11 cancer registries covering a population of 33 million people. Included were 15 685 patients diagnosed with cervical cancer from 1997 to 2006. Period analysis was performed to calculate the five-year relative survival (RS) 2002-2006. Trends in survival between 2002 and 2006 were examined using model-based period analysis. Age-adjustment was done using five age groups (15-44, 45-54, 55-64, 65-74, and 75 + years). Results. Overall, age-adjusted five-year relative survival in 2002-2006 was 64.7%. A strong age gradient was observed, with five-year RS decreasing from 81.7% in age group 15-49 years to 46.3% in age group 70 + years. Prognosis furthermore strongly varied by stage, with age-adjusted five-year RS reaching 84.6% for localized, 48.2% for regional, and 17.9% for distant stage. From 2002 to 2006, a significant improvement (4.7 percent units) in overall age-adjusted five-year RS was seen. The improvement was most pronounced for age groups 55-64 years (from 54.2 to 65.6%) and 65-74 years (from 50.0 to 58.1%). Conclusion. In this first comprehensive population-based study from Germany, prognosis of cervical cancer strongly varied by age and stage. Prognosis continued to improve, in particular in age range 55-74 years, in the five-year period assessed. 相似文献
75.
目的:研究国产美罗培南用于抗感染治疗的临床疗效和安全性.方法:将30例中、重度急性细菌性感染患者按随机对照平行法分成2组,治疗组14例,给予美罗培南0.5g,q8h,静脉滴注;对照组16例,给予泰能(亚胺培南/西司他丁)1.0g,q8h,静脉滴注.两药疗程均为7~10d.结果:两组的临床痊愈率均为50%;临床有效率治疗组和对照组分别为85.7%和87.5%;细菌清除率分别为84.6%和85.7%;不良反应发生率分别为14.3%和18.8%.以上指标两组差异均无显著性(P>0.05).结论:国产新药美罗培南用于抗感染治疗安全有效. 相似文献
76.
目的对不同产地牡丹皮饮片进行质量评价。方法采用化学及仪器分析的方法测定3种不同产地牡丹皮饮片的水分、灰分、浸出物、丹皮酚、丹皮总苷及丹皮多糖含量。结果不同产地牡丹皮饮片有效成分含量有显著差异。结论3种不同产地的牡丹皮饮片样品中,安徽铜陵牡丹皮饮片质量最优。 相似文献
77.
The cholinergic system plays an importantrole in the control of heart rate and myocardialcontractility[1] .The inotropic and chronotropic ef-fects are partly regulated by the cytosolic Ca2 + lev-el( [Ca2 + ]i) .Muscarine receptor agonist,Arecol-ine ( Are) ,is a kind of alkaloid extracted from theseeds of areca.It had been reported that Are hadnegative inotropic and negative chronotropic effectson isolated guinea pig atria[2 ] ,but its effects oncalcium mobilization was unclear. In order to i… 相似文献
78.
目的探讨不稳定性心绞痛患者血清hs—CRP、TnI、CK—MB变化及测定的临床意义。方法利用乳胶增强免疫比浊法和电化学发光法,对154例健康人群、112例uA患者、68例SA患者检测其血清hs—CRP、TnI和CK—MB的水平。结果UA组hs-CRP、TnI、CK—MB水平明显高于SA组(P〈0.01),更远远高于健康组(P〈O.01),并且sA组此三项检测也明显高于健康组(P〈0.05),UA组和SA组及健康组存在显著差异。结论如果将hs—CRP、TnI、CK—MB联合检测,对冠心病的早期诊断,尤其是对不稳定性心绞痛的早期发现及危险性预测,具有重大的现实意义。 相似文献
79.
A. S. MEE & J. L. ROWLEY THE LANSOPRAZOLE CLINICAL RESEARCH GROUP 《Alimentary pharmacology & therapeutics》1996,10(5):757-763
Background: Lansoprazole, a substituted benzimidazole, is a proton pump inhibitor which is highly effective in the control of 24-h intragastric acidity. The aim of this multicentre, randomized, double-blind study was to compare lansoprazole 30 mg once daily and omeprazole 20 mg once daily in the symptom relief and healing of patients with reflux oesophagitis. Methods: Six hundred and four patients with endoscopically proven oesophagitis and a recent history of heartburn were randomly assigned to receive lansoprazole 30 mg or omeprazole 20 mg daily for 4–8 weeks. Daily assessment of symptoms was made by the patient using a 100-mm Visual Analogue Scale. Clinical symptoms were evaluated at weeks 0, 1, 4 and 8. Endoscopic assessment of healing, defined by normalization of the oesophageal mucosal appearance, was made at weeks 4 and 8. Results: Two hundred and eighty-two patients in the lansoprazole group and 283 patients in the omeprazole group were eligible for inclusion in the per protocol analysis. At 3 days, there was a significant improvement in daytime symptoms of heartburn for patients in the lansoprazole group compared with the omeprazole group (P=0.05). A similar but non-significant trend was seen at 7 days (P=0.18). Clinical assessment at 7 days demonstrated significant improvement in daytime epigastric pain in the lansoprazole group compared with the omeprazole group (P=0.03), with a similar but non-significant trend in night-time epigastric pain (P=0.07). Healing rates of oesophagitis at 4 and 8 weeks were 70 and 87%, respectively, with lansoprazole, and 63 and 82%, respectively, with omeprazole. Logistic regression analysis of the cumulative healing rates, which included baseline factors affecting outcome, resulted in an odds ratio of 1.46 (95% CI=0.87–2.45), suggesting a higher chance of being healed with lansoprazole treatment compared with omeprazole treatment. A total of 615 adverse events were reported by 308 (51%) patients during the study period. The majority of events were mild in nature and the incidence was similar in both treatment groups. The most frequently reported events were headache, diarrhoea and nausea. Conclusion: Lansoprazole provides greater symptom relief compared with omeprazole during the first week of treatment. Both treatments were effective in healing oesophagitis. 相似文献
80.
J. F. LUCÍA J. A. AZNAR L. ABAD‐FRANCH R. R. ESCUIN V. JIMÉNEZ‐YUSTE R. PÉREZ J. BATLLE I. BALDA G. ALPEROVICH R. PARRA ON BEHALF OF THE SPANISH HAEMOPHILIA EPIDEMIOLOGICAL STUDY WORKING GROUP 《Haemophilia》2011,17(1):75-80
Summary. The Spanish Epidemiological Study in Haemophilia carried out in 2006 enrolled 2400 patients [2081–86.7% with haemophilia A (HA) and 319–13.3% with haemophilia B]; 465 of them (19.4%) were on prophylaxis. These rates were higher in patients with severe haemophilia (45.4%) and severe paediatric cases (72.5%). On the basis of information recorded in this study, we analysed the current situation of prophylaxis therapy administered to patients with HA in Spain, as well as their orthopaedic status. Prophylaxis was used in 399 (19.2%) patients with HA; such prophylaxis was primary (PP) in 20.3% and secondary (SP) in 75.9% of cases. Among severe HA patients, 313 (45.9%) were on prophylaxis (22.3% on PP and 74.7% on SP). Taking into account the patients’ age, 34.7% of severe HA adults were on prophylaxis (6% PP and 92.1% SP), whereas 71.5% of severe HA paediatric patients (40.5% PP and 55.4% SP) received this kind of treatment. Established haemophilic arthropathy (EHA) was detected in 142 from 313 severe HA patients (45.3%) on prophylaxis, but only in 2.9% of patients under PP vs. 59% of patients receiving SP. There was no EHA in adult severe HA patient on PP, whereas 70.4% on SP had joint damage (P < 0.00001). Among paediatric severe HA patients, EHA was detected in 3.3% under PP and 37.8% under SP (P < 0.00001). In conclusion, our data suggest that an early initiation of prophylaxis avoids EHA in the long‐term in patients with severe HA. We should emphasize the early onset of prophylaxis regimens. 相似文献