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161.
José Ramón Cansino Alcaide Luis Martínez-Piñeiro 《Clinical & translational oncology》2006,8(3):148-152
Summary Genes involved in cancer generation are usually tumor suppressors and oncogenes. Progressive genetic alterations in these
genes are involved in the mechanisms of tumorigenesis. In prostate cancer, additionally several chromosomal loci that should
harbor mutated genes have been proposed. Some genes have been found altered in prostate cancer, such as PTEN, TP53, AR, RNASEL
(HPC1), ELAC2 (HPC2), CDKN2A and MSR1 and those can be natural targets for new strategies of treatment. Besides, gene therapy
has been suggested to be suitable for prostate cancer treatment. This approach includesex vivo corrective therapy, suicide, and antisense therapy. 相似文献
162.
163.
Carlos Bada Nilton Yhuri Carreazo Juan Pablo Chalco Luis Huicho 《Revista paulista de medicina》2007,125(3):150-154
CONTEXT AND OBJECTIVE: Many children with acute lower respiratory tract infections (ALRI) present to the emergency ward with concurrent wheezing. A chest x-ray is often requested to rule out pneumonia. We assessed inter-observer agreement in interpreting x-rays on such children. DESIGNS AND SETTING: Prospective consecutive case study at Instituto de Salud del Ni?o, Lima, Peru. METHODS: Chest x-rays were obtained from eligible children younger than two years old with ALRI and concurrent wheezing who were seen in the emergency ward of a nationwide pediatric referral hospital. The x-rays were read independently by three different pediatric residents who were aware only that the children had a respiratory infection. All the children had received inhaled beta-adrenergic agonists before undergoing chest x-rays. Lobar and complicated pneumonia cases were excluded from the study. RESULTS: Two hundred x-rays were read. The overall kappa index was 0.2. The highest individual kappa values for specific x-ray findings ranged from 0.26 to 0.34 for rib horizontalization and from 0.14 to 0.31 for alveolar infiltrate. Inter-observer variation was intermediate for alveolar infiltrate (kappa 0.14 to 0.21) and for air bronchogram (kappa 0.13 to 0.23). Reinforcement of the bronchovascular network (kappa 0.10 to 0.16) and air trapping (kappa 0.05 to 0.20) had the lowest agreement. CONCLUSIONS: There was poor inter-observer agreement for chest x-ray interpretation on children with ALRI and concurrent wheezing seen at the emergency ward. This may preclude reliable diagnosing of pneumonia in settings where residents make management decisions regarding sick children. The effects of training on inter-observer variation need further studies. 相似文献
164.
反式二羟环氧苯并芘对人支气管上皮细胞中HER2/neu基因表达的影响 总被引:1,自引:0,他引:1
目的探讨环境致癌物苯并(a)芘代谢物反式二羟环氧苯并芘(BPDE)对人支气管上皮细胞HER2/neu基因表达的影响。方法利用半定量RT-PCR、SYBR GreenI实时定量RT-PCR(QRT-PCR)、Western blot及免疫细胞化学方法分别检测经2.0μmol/L反式BPDE诱发人支气管上皮细胞恶性转化细胞(16HBE-T)与对照DMSO溶剂组未恶性转化细胞(16HBE-N)之间HER2/neu基因mRNA和蛋白表达水平的差异,及两组细胞内HER2/neu蛋白表达定位分析。结果经几种不同方法检测反式BPDE恶性转化人支气管上皮细胞中HER2/neu基因mRNA和蛋白水平都比对照溶剂组细胞(16HBE-N)表达显著升高(P<0.05)。HER2/neu蛋白定位在胞膜。结论反式BPDE诱发人支气管上皮细胞恶性转化存在HER2/neu表达增高,其可能与原癌基因HER2/neu被激活作用有关。 相似文献
165.
166.
André H. Eriksson Manthena V.S. Varma Everett J. Perkins Cheryl L. Zimmerman 《Journal of pharmaceutical sciences》2010,99(3):1574-1581
LY354740 is a potent mGlu2/3 agonist with a limited oral bioavailability. Its alanyl prodrug, LY544344, showed high affinity to the intestinal peptide transporter PEPT1, and improved the oral bioavailability of LY354740 in various animal models. The aim of the present study was to investigate the mechanism of in vivo absorption of the dipeptidic prodrug LY544344. The permeabilities of LY544344 and LY354740 were examined in the rat in situ single‐pass intestinal perfusion model. The intestinal absorptive flux of LY354740 was shown to be very low in comparison with LY544344. The absorptive flux of LY544344 could best be described by a Michaelis–Menten process in parallel with a linear process. The estimated parameters were: Jmax = 26.7 × 10?5 µmol/(cm2‐s), Km = 2.6 mM. The absorptive permeability of LY544344 was reduced to approximately 5% of control in the presence of excess Gly‐Sar, a known PEPT1 substrate. Intracellular accumulation of LY354740 and LY544344, estimated postperfusion, showed high levels of LY354740 over LY544344 at all perfusate concentrations studied. However, there was a decline in the intracellular ratio of LY354740 to LY544344 at higher concentrations, suggesting that the metabolic activation to release LY354740 is saturable. © 2009 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1574–1581, 2010 相似文献
167.
Ohne Zusammenfassung 相似文献
168.
169.
A tumor-targeted and conditionally replicating oncolytic adenovirus vector expressing TRAIL for treatment of liver metastases. 总被引:3,自引:0,他引:3
Pavel Sova Xiao-Wei Ren Shaoheng Ni Kathrin M Bernt Jie Mi Nancy Kiviat André Lieber 《Molecular therapy》2004,9(4):496-509
We have constructed a new capsid-modified adenovirus (Ad) vector that specifically replicates in tumor cells and expresses TNF-related apoptosis-inducing ligand (TRAIL). The Ad capsid contains short-shafted fibers derived from Ad serotype 35, which allow for efficient infection of malignant tumor cells, and largely avoids innate toxicity after intravenous application. Replication-dependent homologous recombination in Ad genomes was used to achieve tumor-specific expression of Ad E1a (to mediate viral replication) and TRAIL (to mediate apoptosis and enhance release of progeny virus from infected cells). We demonstrated that our oncolytic vector (Ad5/35.IR-E1A/TRAIL) induced apoptosis in human tumor cell lines derived from colorectal, lung, prostate, and liver cancer. Both in vitro and in vivo tumor models showed efficient intratumoral spread of this vector. In a model for metastatic colon cancer, tail vein infusion of Ad5/35.IR-E1A/TRAIL resulted in elimination of preestablished liver metastases. Intravenous injection of this vector caused a transient elevation of serum glutamic pyruvic transaminase in tumor-bearing mice, which we attributed to factors released from apoptotic tumor cells. Liver histology analyzed at day 14 after virus injection did not show signs of hepatocellular damage. This new oncolytic vector represents a potentially efficient means for gene therapy of metastatic cancer. 相似文献
170.
探讨安徽省立医院规范临床新技术、新项目管理的做法:一是明确新技术、新项目的管理范畴和管理部门;二是抓好申报与管理的三个环节;三是管理与激励并重,实现两个效益稳步增长.并结合三年来的实践谈自身体会. 相似文献