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91.
We report a study of cell proliferative factors Ki67, PCNA and p53 oncoprotein in 55 patients with bladder tumors. Fifty-three of the patients were male and two were female, with a mean age of 56.6 and 68.5 years, respectively. These tumors were of transitional cell type in 97.9% of the cases. Staging was, respectively, pTis (4.76%), pTa (30.9%), pT1 (19.04%), pT2 (23.8%) and Pt3 (21.4%). Our study of proliferative nuclear markers Ki67 showed that cell proliferation increased in bladder tumors according to grade in the same stage. This variation was highlighted by our results for PCNA but was not verified for Ki67. However, these results revealed an increase of cell proliferation for a same grade (grade I and II) in different stages (pTa, pT1, pT2) for PCNA; this was not ascertained for Ki67. The study of p53 oncoprotein showed that detection of mutated p53 protein increased according to grade only for grades II and III and to stage only when moving from pTis to superficial tumors (pTa, pT1) and to deep tumors (pT2, pT3), thus individualizing two groups without significant variation within these groups. A variation according to grade in the same stage was noted only for stages pT1 and pT2. A variation for a same grade (grades II and III) was reported between stages pTa, pT1 and pT2. The combined study of Ki67, PCNA and p53 oncoprotein showed a prognostic correlation between these three markers in general.  相似文献   
92.
BACKGROUND AND PURPOSE: For some treatment sites, there is evidence in the literature that five to nine equi-angular input beam directions are enough for generating IMRT plans. For oesophagus cancer, there is a report showing that going from four to nine beams may even result in lower quality plans. In this paper, our previously published algorithm for automated beam angle selection (Cycle) has been extended to include segmented IMRT. For oesophagus cancer patients, we have investigated whether automated orientation selection from a large number of equi-angular input beam directions (up to thirty-six) for IMRT optimisation can result in improved lung sparing. MATERIALS AND METHODS: CT-data from five oesophagus patients treated recently in our institute were used for this study. For a prescribed mean PTV dose of 55 Gy, Cycle was used in an iterative procedure to minimise the mean lung dose under the following hard constraints: standard deviation for PTV dose inhomogeneity 2% (1,1 Gy), maximum spinal cord dose 45 Gy. Conformal radiotherapy (CFRT) and IMRT plans for a standard four field oesophagus beam configuration were compared with IMRT plans generated by automated selection from nine or thirty-six equi-angular input beam orientations. Comparisons were also made with dose distributions generated with our commercial treatment planning system (TPS), and with observations in the literature. RESULTS: Using Cycle, automated orientation selection from nine or thirty-six input beam directions resulted in improved lung sparing compared to the four field set-ups. Compared to selection from nine input orientations, selection from thirty-six directions did always result in lower mean lung doses, sometimes with even fewer non-zero weight beams. On average only seven beams with a non-zero weight were enough for obtaining the lowest mean lung dose, yielding clinically feasible plans even in case of thirty-six input directions for the optimisation process. With our commercial TPS we observed the same contra-intuitive, unfavourable results as reported in the literature; nine field equi-angular IMRT plans had substantially higher mean lung doses than plans for the conventional four field set-ups. For all cases, the Cycle plans generated from nine equi-angular input directions were superior compared to similar plans generated with our commercial TPS. CONCLUSIONS: For the studied oesophagus cancer patients the best plans for IMRT were obtained with Cycle, using automated beam orientation selection from thirty-six input beam directions. The lowest mean lung doses could be obtained with, on average, a selection of only seven beams with non-zero weight.  相似文献   
93.
Rats were exposed to three levels of bromobenzene, sampled at 6, 24, and 48 h, and liver gene expression profiles were determined to identify dose and time-related changes. Expression of many genes changed transiently, and dependent on the dose. Few changes were identified after 6 h, but many genes were differentially expressed after 24 h, while after 48 h, only the high dose elicited large effects. Differentially expressed genes were involved in drug metabolism (upregulated GSTs, mEH, NQO1, Mrps, downregulated CYPs, sulfotransferases), oxidative stress (induced HO-1, peroxiredoxin, ferritin), GSH depletion (induced GCS-l, GSTA, GSTM) the acute phase response, and in processes like cholesterol, fatty acid and protein metabolism, and intracellular signaling. Trancriptional regulation via the electrophile and sterol response elements seemed to mediate part of the response to bromobenzene. Recovery of the liver was suggested in response to BB by the altered expression of genes involved in protein synthesis and cytoskeleton rearrangement. Furthermore, after 48 h, rats in the mid dose group showed no toxicity, and gene expression patterns resembled the normal situation. For certain genes (e.g., CYP4A, metallothioneins), intraday variation in expression levels was found, regardless of the treatment. Selected cDNA microarray measurements were confirmed using the specific and sensitive branched DNA signal amplification assay.  相似文献   
94.
Paediatric organ donation represents a small fraction of overall organ donation in Australia and New Zealand and indeed world‐wide. Many factors contribute to low donation rates including low paediatric intensive care mortality, consent rates and medical suitability relating to disease, age and size. In the past decade, the re‐emergence of donation after circulatory death has changed the landscape for the paediatric population. This article reviews the current status and challenges of organ donation for the paediatric population.  相似文献   
95.
子宫动脉栓塞术治疗子宫肌瘤42例临床分析   总被引:79,自引:0,他引:79  
Chen C  Lu J  Liu P  Yu L  Ma B  Liu P 《中华妇产科杂志》2002,37(1):8-11
目的 探讨子宫动脉栓塞术(UAE)治疗子宫肌瘤的疗效。方法 选择42例子宫肌瘤患者,以Seldinger技术完成单侧股动脉插管,根据数字减影血管造影(DSA)检查结果,选用管径为4-5F(1F=0.33mm)的脾管、肝管或cobra导管,或选用3F微导管,插管至双侧子宫动脉并经DSA检查证实后,以携带有抗生素的明胶海绵颗粒栓塞该处血管。结果 DSA检查发现,子宫肌瘤血液供应丰富。UAE治疗6-12个月后,子宫肌瘤患者的临床症状明显缓解,月经量减少26.3%-75.2%;UAE治疗后第12个月、第18个月肌瘤体积分别缩小77.7%、83.0%,子宫体积分别缩小54.9%、62.7%。术后有不同程度的下腹痛、低热,持续1-3周,经对症处理后症状逐渐消失。结论 UAE可有效地缩小肌瘤及子宫的体积,并明显改善子宫肌瘤患者的临床症状。  相似文献   
96.
97.
<正>The trigeminal nerve and its peripheral branches are susceptible to injury in the dental practice due to surgical removal of impacted third molars and placement of dental implants.Although peripheral trigeminal nerve injuries can undergo spontaneous regeneration,some injuries may be permanent with varying degrees of continued sensory impairment and neuropathic pain ranging from mild numbness to complete anaesthesia (Tay and Zuniga,2007).Adult neurons require continued neurotrophic suppo...  相似文献   
98.
99.
Introduction: Tunisia is experiencing a double burden of morbidity, characterized by the explosion of cardiovascular diseases and their risk factors including arterial Hypertension. The objective of this study, based on the HSHS cohort (Hammam Sousse Sahloul Heart Study), was to determine the prevalence of hypertension in the general population and to identify its predisposing factors. Methods: HSHS is a cardiovascular health promotion initiative in the city of Hammam Sousse (Tunisia). The study was conducted via a random sample of households, using the WHO PEV technique, made up of 33 clusters, of 33 households each. All people aged 20 and over, included, benefited from a questionnaire, a physical examination and a biological assessment. The Systolic Blood Pressure (SBP) and the Diastolic Blood Pressure (DBP) were measured from the average of the last two measurements, by an OMRON type tensiometer, of suitable width. These prevalences were adjusted according to sex and age group, by their weighting coefficients in the general population, and they were accompanied by their 95% CIs. Binary logistic regression was conducted to identify independent factors associated with hypertension. Results: The study population was composed of 481 men (33.4%) and 960 women (66.6%), with an average age of 49.6±16.35 years in males (M) and 46.6±16.18 in females (F). In addition to the family history of hypertension, the sufficient weekly consumption of vegetables and fruits was low (M: 32.4%, F: 24.9%). The adjusted rate of hypertension in the adult study population was 32.5%, 95%CI[31.9-33.1] (M: 36.4%, 95%CI[35, 5-37.3]; F: 28.4%; 95% CI[27.6-29.2]), reaching in the age group of 60 years and above: M: 74.6% (95%CI[66.9-82.3], F: 82.7% (95%CI[73.8-83.6]) Multivariate analysis identified five independent factors significantly associated with hypertension: male sex (ORa=1.55 [1.18-2.03]), age over 40 years (ORa=6.54[4.70-9.11]), low level of schooling (ORa=1.80 [1.36-2.38]), low physical activity (ORa=1.42[1.07-1.88]) and high socio-economic level (ORa=1 .84 [1.30-2.63]). Conclusion: The HSHS study confirmed the high prevalence of hypertension, and the extent of its low detection and control. Hence the need for a universal approach to health promotion, oriented towards the general population, piloted by its local organizations, based on the adoption of a healthy lifestyle, and centered on physical activity.  相似文献   
100.
Ferroelectric property that induces electrocaloric effect was investigated in Ba(GexTi1−x)O3 ceramics, known as BTGx. X-ray diffraction analysis shows pure perovskite phases in tetragonal symmetry compatible with the P4mm (No. 99) space group. Dielectric permittivity exhibits first-order ferroelectric-paraelectric phase transition, confirmed by specific heat measurements, similar to that observed in BaTiO3 (BTO) crystal. Curie temperature varies weakly as a function of Ge-content. Using the direct and indirect method, we confirmed that the adiabatic temperature change ΔT reached its higher value of 0.9 K under 8 kV/cm for the composition BTG6, corresponding to an electrocaloric responsivity ΔT/ΔE of 1.13 × 10−6 K.m/V. Such electrocaloric responsivity significantly exceeds those obtained so far in other barium titanate-based lead-free electrocaloric ceramic materials. Energy storage investigations show promising results: stored energy density of ~17 mJ/cm3 and an energy efficiency of ~88% in the composition BTG5. These results classify the studied materials as candidates for cooling devices and energy storage applications.  相似文献   
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