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91.
Background and aims Colorectal cancer is a major cause of cancer death in European countries and differences in screening implementation may in part explain USA vs European survival differences. Despite the evidence, no study has evaluated the population colorectal cancer screening (CCS) coverage in any European country. We aimed to index the current CCS practices among a large sample of Greek healthy adults. Materials and methods The study was designed as a cross-sectional survey. Screening practice habits of 5,259 healthy adults, aged 50–80, were surveyed. Both overall and screening practices of stool occult blood test (SOBT), digital rectal examination (DRE), and colonoscopy or sigmoidoscopy (COL/SIG) were analyzed. Results Of the population analyzed, 90.1% declared that they were interested in cancer prevention activities. Overall SOBT practice rate within the last 2 years was 4.77%. When only screening procedures were analyzed, this percentage shrank to 1.73%. Overall and screening COL/SIG rates within the last 10 years were 8.76 and 1.74%, respectively. The respective proportions of individuals who underwent DRE were 14.54 and 5.2%. Evidence-based screening practices were influenced by age, family history of colorectal cancer, profession, and educational level; however, SOBT and colonoscopy/sigmoidoscopy did not overcome 4.1 and 4.6% in any subpopulation analyzed. Conclusion The level of CCS coverage among the examined sample of Greek adults was discouraging. Surveys among other European countries are encouraged.  相似文献   
92.
BACKGROUND: Insulin-like growth factor 1 (IGF-1), transforming growth factor beta 1 (TGFbeta1), and interleukin 6 (IL-6), act as survival factors inhibiting chemotherapy-induced apoptosis in PC-3 human prostate cancer cells, in vitro. MATERIALS AND METHODS: To study the intracellular pathways activated by these survival factors we performed a comparative genomic analysis using oligonucleotide microarray chips. A validation by real time-PCR was also performed for the genes of interest. RESULTS: The expression data derived were analysed using various normalization algorithms. The differentially expressed genes were clustered and their ontological annotations were statistically tested to provide evidence for possible deregulated biological processes on the action of the aforementioned survival factors. Emphasis was given on the regulation and the role of the genes AKR1C1, SDPR and GADD45B in the survival pathways of prostate cancer cells, whose expression was also validated by real time-PCR. CONCLUSION: The overall analyses reveal an overrepresentation of differentially expressed genes related to cellular processes such as cell cycle regulation, lipid metabolism and steroid biosynthesis.  相似文献   
93.
先天性无肛直肠舟状窝瘘手术186例   总被引:1,自引:0,他引:1  
杨合英  李苏宁  张谦  许华峰  王家祥 《医学争鸣》2005,26(14):F003-F003
1临床资料1988-06/2003-12我院共186例,均为女性,无肛门,其中0~6月龄21例,0.5~1岁96例,1~3岁53例,3~8岁15例,13岁1例.以大便从会阴部舟状窝瘘口处排出而就诊,患儿有不同程度的排便困难,严重时伴腹胀呕吐,多数患儿有营养不良性贫血.瘘口直径0.3~0.6 cm,直肠盲端到肛穴皮肤之间的距离1.0~2.5 cm,属于中、低位肛门直肠畸形.本组有3例合并先天性心脏病-室间隔缺损,2例合并骶前囊肿,1例合并脐疝.  相似文献   
94.
学报发展之我见   总被引:3,自引:0,他引:3  
国家最新的统计数据显示,在我国5000种科技期刊中,高等院校所办的期刊已经达到1347种,其中绝大多数为学报;在我国1124种医学期刊中,学报也占有较大的比例.尽管学报的数量不少,但从期刊的综合评价体系来看,其中高质量者寥寥无几;而获得过“首届国家期刊奖,第二届国家期刊奖提名奖”的第四军医大学学报无疑是其中的佼佼者、尽管我们取得过辉煌的成绩,但依旧无法回避今日严峻的现实.要使学报能够健康地发展,我认为以下几点不容忽视.  相似文献   
95.
96.
We explored the feasibility of imaging myocardial perfusion and of demonstrating the flow changes in response to reduction of cardiac work non-invasively in anesthetized mice using high spatial resolution, dedicated small-animal positron emission tomography (microPET). In 31 C57BL/6 mice anesthetized with pentobarbital or isoflurane, 13N-ammonia was injected intravenously and images were recorded with microPET from 4 to 20 min. Fifteen mice (group 1) were studied consecutively at baseline (BL) and after reduction of heart rate (HR) with intraperitoneal injection of clonidine (CLN) to investigate effects of CLN-induced reduction of cardiac work on myocardial 13N-ammonia uptake. Eight mice (group 2) were imaged repeatedly at BL and eight mice (group 3) twice after CLN to examine reproducibility. Total myocardial 13N-ammonia accumulation was determined from the transaxial images and normalized for injected dose (%ID). HR was 412±97 beats/min at BL and 212±44 beats/min after CLN (P<0.0001). In group 1, the %ID significantly decreased from 1.50%±0.27% at BL to 1.29%±0.28% after CLN (P<0.0001). In groups 2 and 3, reproducibility of %ID was good (y=0.96x+0.105, SEE=0.212%, r 2=0.749, P<0.0001). In conclusion, 13N-ammonia microPET imaging demonstrated non-invasively a reduction of myocardial perfusion induced by clonidine in mice. We believe this study is of importance as the first report on myocardial perfusion imaging and flow validation in in vivo mouse hearts with a left ventricular size of only 5 mm using 13N-ammonia and PET. MicroPET will aid in elucidating cardiac pathophysiology in transgenic mice and monitoring effects of gene therapies on myocardial perfusion.  相似文献   
97.
Food additives are widely used for technological purposes and their presence is often substantial daily diet. They have also been accused forvarious toxic reactions in humans. The toxicity of the food color tartrazine, the preservatives sodium nitrate and sodium benzoate, and the antioxidant BHT, was studied using the protozoan Tetrahymenapyriformis as a toxicological model. The 4 food additives were added to Tetrahymena cultures and DNA content of the protozoan nuclei measured by an image analysis system. These food additives caused a statistically significant increase in DNA content suggesting stimulation of the mitotic process. This system may contribute to the investigation of the cellular action of food additives, since mitogenic stimuli substantially alter susceptibility to chemical carcinogenesis.  相似文献   
98.
The feasibility and limits in performing tomographic bioluminescence imaging with a combined optical-PET (OPET) system were explored by simulating its image formation process. A micro-MRI based virtual mouse phantom was assigned appropriate tissue optical properties to each of its segmented internal organs at wavelengths spanning the emission spectrum of the firefly luciferase at 37 degrees C. The TOAST finite-element code was employed to simulate the diffuse transport of photons emitted from bioluminescence sources in the mouse. OPET measurements were simulated for single-point, two-point and distributed bioluminescence sources located in different organs such as the liver, the kidneys and the gut. An expectation maximization code was employed to recover the intensity and location of these simulated sources. It was found that spectrally resolved measurements were necessary in order to perform tomographic bioluminescence imaging. The true location of emission sources could be recovered if the mouse background optical properties were known a priori. The assumption of a homogeneous optical property background proved inadequate for describing photon transport in optically heterogeneous tissues and led to inaccurate source localization in the reconstructed images. The simulation results pointed out specific methodological challenges that need to be addressed before a practical implementation of OPET-based bioluminescence tomography is achieved.  相似文献   
99.
Radiation‐induced brain disorders (RIBD) are uncommon and they are grave sequelae of conventional radiotherapy. In the present report, we describe the clinical spectrum of RIBD in 11 patients who received post‐surgery conventional megavoltage irradiation for residual pituitary tumours. Of these 11 patients (nine men, two women), seven had been treated for non‐functioning pituitary tumours and four for somatotropinomas. At the time of irradiation the age of these patients ranged from 30 to 59 years (mean, 39.4 ± 8.3; median, 36) with a follow‐up period of 6?96 months (mean, 18.3 ± 26.4; median, 11). The dose of radiation ranged from 45 to 90 Gy (mean, 51.3 ± 13.4; median, 45), which was given in 15?30 fractions (mean, 18.6 ± 5.0; median, 15) with 2.8 ± 0.3 Gy (median, 3) per fraction. The biological effective dose calculated for late complications in these patients ranged from 78.7 to 180 Gy (mean, 99.1 ± 27.5; median, 90). The lag time between tumour irradiation and the onset of symptoms ranged from 6 to 168 months (mean, 46.3 ± 57.0; median, 57). The clinical spectrum of RIBD included new‐onset visual abnormalities in five, cerebral radionecrosis in the form of altered sensorium in four, generalized seizures in four, cognitive dysfunction in five, dementia in three and motor deficits in two patients. Magnetic resonance imaging (MRI)/CT of the brain was suggestive of radionecrosis in eight, cerebral oedema in three, cerebral atrophy in two and second neoplasia in one patient. Associated hormone deficiencies at presentation were hypogonadism in eight, hypoadrenalism in six, hypothyroidism in four and diabetes insipidus in one patient. Autopsy in two patients showed primitive neuroectodermal tumour (PNET) and brainstem radionecrosis in one, and a cystic lesion in the left frontal lobe following radionecrosis in the other. We conclude that RIBD have distinctive but varying clinical and radiological presentations. Diabetes insipidus and PNET as a second neoplastic disorder in adults following pituitary irradiation have not been reported previously.  相似文献   
100.
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