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排序方式: 共有921条查询结果,搜索用时 10 毫秒
911.
Sciarra A Panebianco V Salciccia S Lisi D Alfarone A Gentilucci A Parente U Cattarino S Passariello R Gentile V 《Urologic oncology》2012,30(5):614-619
PurposeTo determine the time-dependent metabolic and angiogenic changes that occur in prostate cancer (CaP) during neoadjuvant hormone therapy (HT), using a combination of MRSI and DCEMR analysis.Materials and methodsThis is a prospective study on a population of non-metastatic CaP submitted to neoadjuvant HT prior to radiation therapy. All cases homogeneously received a 6-month period of neoadjuvant HT using leuprorelin acetate 7.5 mg every 28 days. In all cases, a MRSI/DCEMR study was performed at baseline (pretreatment) and at regular intervals (4, 12, 24 weeks) during HT. Serum PSA was measured at baseline and at the same intervals (4, 12, 24 weeks). All MRI examinations were performed on a commercially available 3 T scanner.ResultsThere was a significant ( P < 0.01) time-dependent loss of all prostate metabolites during HT. In regions of CaP no significant variation in the absolute value of metabolites was reported at 1-month interval and a higher variation was observed at 24-week compared with 12-week interval. A complete metabolic atrophy was a common feature (30%) at a 24-week interval of HT, but not at short (4-week 0%), and lower at an intermediate interval (12-week 10%). At DCEMR, onset time and time to peak parameters significantly (P < 0.05) increased at 12- and 24-week intervals.ConclusionsTo individualize neoadjuvant HT courses prior to definitive treatment, the combination of MRSI and DCEMR may represent a valid noninvasive method, and the addition to PSA data could be used to better assess the time-dependent efficacy of HT in our patients. 相似文献
912.
目的:观察胰岛素对严重烧伤所致的急性肺损伤的保护效应。方法:实验于2006-01/08在解放军第四军医大学西京医院全军烧伤中心实验室完成。取成年雄性SD大鼠36只,随机分成3组,每组12只:①烫伤 胰岛素组:水浴锅94℃,20s,制备30%总体表面积全层皮肤烫伤模型,伤后即刻腹腔注射生理盐水40mL/kg,并皮下注射胰岛素3U/kg。②烫伤组:造模和腹腔注射同烫伤 胰岛素组,皮下注射等体积生理盐水。③假烫组:用室温水浴模拟烫伤过程,伤后不给予补液。烫伤24h后,收集动脉血测定超氧化物歧化酶活性,收集支气管肺泡灌洗液测定蛋白含量,取肺组织进行苏木精-伊红染色观察病理变化,并测定髓过氧化物酶活性,同时电镜观察胸主动脉血管内皮细胞变化情况。结果:36只大鼠进入结果分析。①肺病理变化:烫伤 胰岛素组肺脏渗出和水肿较烫伤组明显减轻。②肺泡灌洗液中蛋白的质量浓度:烫伤组和烫伤 胰岛素组高于假烫组[(702.9±169.5),(486.5±149.2),(240.5±140.7)mg/L,P<0.05],烫伤 胰岛素组低于烫伤组(P<0.05)。③肺脏髓过氧化物酶活性:烫伤 胰岛素组低于烫伤组[(36.01±8.17),(59.51±12.50)nkat/g,P<0.05],与假烫组比较差异不显著。④血清超氧化物歧化酶活性:烫伤组和烫伤 胰岛素组低于假烫组[(2.27±0.18),(2.63±0.19),(2.81±0.21)mkat/L,P<0.01,0.05],烫伤 胰岛素组高于烫伤组(P<0.01)。⑤电镜下可见烫伤 胰岛素组内皮细胞损伤较烫伤组轻。结论:严重烧伤早期外源性胰岛素干预后可减轻急性肺损伤,具有明显的肺脏保护作用,这种作用可能与胰岛素的内皮细胞保护效应有关。 相似文献
913.
M Adams ; TH Lee ; MP Busch ; J Heitman ; GJ Marshall ; GF Gjerset ; JW Mosley 《Transfusion》1993,33(6):504-508
Storage of lymphocytes for later use in prospective epidemiologic studies of blood donors and transfusion recipients has been limited by the cost of separating peripheral blood mononuclear cells (PBMCs). When the Transfusion Safety Study began in 1985, it was decided to establish a cell repository of cryopreserved buffy coat (BC) samples, and thus far over 20,000 samples have been accumulated from enrolled subjects. To determine if these specimens could be used for polymerase chain reaction, a simple thawing and pelleting technique for recovering hemoglobin-free total white cells (WBCs) was developed. To validate the technique, parallel analysis was conducted of BCs, whole blood (WB), and PBMC samples from human immunodeficiency virus type 1 (HIV-1)- seropositive subjects. Immediate postthaw cell courts of 29 frozen- thawed (F-T) WB and BC samples averaged 90 percent of the prefreeze (input) values. Representative WBC populations were obtained by immediate pelleting. Amplification of HIV-1 gag sequences from F-T BCs and F-T WB was 94 and 75 percent, respectively, which is as sensitive as that obtained with freshly separated PBMC lysates. Quantitative HIV- 1 proviral load analysis by serial dilution of 23 F-T BCs and 8 WB lysates showed results comparable to those obtained with lysates of fresh PBMCs. Values for WBC differential and immunophenotyping could be applied to express viral load relative to total WBCs, PBMCs, or CD4+ cells. These results establish the basis for simplified virologic analysis of cryopreserved BC or WB specimens. 相似文献
914.
The changing distribution and survival of colorectal carcinoma: an epidemiological study in an area of northern Italy 总被引:2,自引:0,他引:2
Sarli L Michiara M Sgargi P Iusco D De Lisi V Leonardi F Bella MA Sgobba G Roncoroni L 《European journal of gastroenterology & hepatology》2005,17(5):567-572
OBJECTIVE: This study analyses the inter-relations of anatomical tumour location, gender, age and incidence rates for colorectal cancer from 1978 to 1999 in an area of northern Italy: the Parma district. METHODS: Data were obtained from the Parma Cancer Registry. Age-adjusted incidence rates were analysed by gender, age and colorectal cancer subsites. In addition, 5 year observed survival rates were determined. RESULTS: In the Parma area, the incidence of colorectal cancer is rising. We have observed a true increase in the rate of the age standardized incidence of right colon cancer, linked to an increased incidence of left colon cancer, while the incidence of rectal cancer has remained constant. The frequency of right-sided colon cancer was higher in aged patients, and in women. Age-standardized relative survival of patients after diagnosis of colorectal cancer between 1992 and 1996 was found to be significantly higher than age-standardized relative survival after diagnosis between 1978 and 1982. CONCLUSIONS: In the Parma area there has been an increased incidence of right colon cancer, linked to an increased incidence of left colon cancer, while the incidence of rectal cancer has remained constant. We feel that this shift, whatever the reason for it, has important implications for the choice of screening techniques. 相似文献
915.
Alfonso Pozio Francesco Bozza Nicola Lisi Rosa Chierchia Francesca Migliorini Roberto Dond Silvana De Iuliis 《Materials》2022,15(13)
Nanostructured cobalt oxide powders as electro catalysts for the oxygen evolution reaction (OER) in an alkaline membrane electrolysis cell (AME) were prepared by flame spray synthesis (FS); an AME’s anode was then produced by depositing the FS prepared cobalt oxide powders on an AISI-316 sintered metal fiber by the electrophoretic deposition (EPD) method. FS powders and the composite electrode were characterized by SEM, XRD, and XPS analysis. The electrode showed an increase in the OER catalytic activity in a KOH 0.5 M solution with respect to commercial materials commonly applied in alkaline electrolysis, demonstrating that the flame spray synthesis of nanoparticles combined with the electrophoretic deposition technique represent an effective methodology for producing an anodic catalyst for alkaline membrane electrolyzers. 相似文献
916.
A priori knowledge of the shelf life of energetic materials (EMs) is relevant due to its direct association with safety and functionality. This paper proposes a quick and reliable approach to predicting the shelf life of EMs whose thermal decomposition is an autocatalytic process once their failure threshold has been defined as a function of the limiting extent of conversion. This approach is based on the assumption of a kinetic law consistent with the autocatalytic behavior and on the subsequent extraction, via a suitable procedure of parameter identification, of the kinetics of thermal decomposition from differential scanning calorimetry (DSC) data gathered under dynamic conditions at three different heating rates. Its reliability is proven for picric acid (PA) through the comparison of kinetic predictions with evaluations of conversion obtained by using high performance liquid chromatography (HPLC) analysis for samples subjected to isothermal and non-isothermal accelerated aging tests, as well as for a sample of naturally aged material, i.e., PA, stored at room temperature for more than 10 years. 相似文献
917.
918.
Th2 cytokines play a pivotal role in the pathogenesis of allergic rhinitis. To investigate the effect of p38 mitogen-activated protein kinase (MAPK) on the production of Th2 cytokines such as IL-4 and IL-5 in allergic rhinitis, a model of allergic rhinitis was established in SD rats. The expression level of p38 MAPK mRNA in PBMCs was detected by means of real time quantitative RT-PCR. The p38 MAPK activity in PBMCs was detected by Western blotting. PBMCs were cultured with various concentrations of p38 MAPK inhibitor SB 239063 or without the treatment, and then IL-4, IL-5 levels of the supernatant were determined by using sandwich ELISA. The results showed that mRNA expression and activity of p38 MAPK in PBMCs were significantly higher in allergic rhinitis rats than in control rats (P〈0.05). The p38 MAPK inhibitor SB 239063 decreased the production of IL-4 and IL-5 in a dose-dependent manner. It is concluded that p38 MAPK plays an important role in the pathogenesis of allergic rhinitis which is associated with Th2 cytokines release. 相似文献
919.
920.