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1.
Rocha Déborah Ribeiro Nery Jaqueline Freire Furini Leonardo Negri Constantino Carlos José Leopoldo Eller Lizziane Kretli Winkelströter Nai Gisele Alborghetti Nakagaki Wilson Romero 《Lasers in medical science》2020,35(8):1703-1709
Lasers in Medical Science - Studies reported the harmful effects of 2,4-D on body tissues, provoking changes in the anatomy and physiology of the kidneys, liver, and testicles. Thus, the objective... 相似文献
2.
背景:组织工程是一个多学科研究的交叉学科,其目标是使人体损伤的组织和器官再生,通过这种假设,几乎所有的动物组织都可以在实验室进行培养。一般的方法是从需要移植的患者身上提取干细胞,在一定的支持条件下允许其生长、增殖、生产为可替换的组织。另一方面,寻找细胞能够互相联结并形成分层结构的合适的支持条件,如基质或支架等非常必要。目前用于烧烫伤治疗的材料有很多种,如胶原,透明质酸、纤维蛋白和聚乳酸及其共聚物。
目的:讨论以新型的生物材料自体血浆为支架对自体成纤维细胞和角质化细胞生长、扩张、增殖的影响。
设计:建立一种真皮再生的方法,将自体成纤维细胞浸于人血浆基质中,排除各种影响样本安全性和排斥反应的问题,应用同样的方法在新的真皮上获取角质化细胞。
时间及地点:实验于2008年在意大利曼多瓦C. Poma医院动物工厂完成。
材料:人角质化细胞和成纤维细胞取自1例58岁乳房切除患者的皮肤碎片。实验得到C. Poma医院独立伦理委员会批准,患者知情同意。
方法:从自体活组织皮肤样本中分离人角质化细胞和成纤维细胞,置于培养瓶中增殖,随后将自体血浆作为皮肤移植形成构造的支架,免疫和免疫组织化学特征显示与正常皮肤相似。
主要观察指标:将血浆样本用甲醛固定,埋入石蜡,苏木精-伊红染色,用显微镜进行细胞计数。所有样本均经免疫组织化学评估。
结果:在血浆基质上获得了多层规则形状的角质化细胞和成纤维细胞,基底膜的形成说明自体血浆是角质化细胞和成纤维细胞的生长、分化、扩展的良好支架,真皮和表皮细胞联结重建皮肤移植与正常皮肤无异。
结论:血浆作为角质化细胞和成纤维细胞分化、扩展的支架表现出良好的性能,同时实验还特别发现成纤维细胞浓缩血浆可以暂时替代皮肤,也是角质化细胞生长的强有力的支架。此外血浆还具有廉价,易于制备等优点。自体角质化细胞和成纤维细胞及自体血浆的应用,可以避免血种类型的免疫排斥反应。这种治疗方法给有慢性缺损并且需要连续移植的患者带来了希望。
doi:10.3969/j.issn.1673-8225.2009.47.001 相似文献
3.
Dietary factors in the risk of bladder cancer 总被引:2,自引:0,他引:2
C La Vecchia E Negri A Decarli B D'Avanzo C Liberati S Franceschi 《Nutrition and cancer》1989,12(1):93-101
The relationship between selected dietary factors and the risk of bladder cancer was investigated in a case-control study conducted in northern Italy. The study included 163 cases and 181 controls who were hospitalized for acute, nonneoplastic or urinary tract diseases. The frequency of consumption of green vegetables and carrots was lower in the cases; thus, the estimated relative risks for the upper vs. the lower tertiles were 0.6 for green vegetables and 0.5 for carrots. Significant inverse trends in risk emerged with estimated carotenoid (as well as retinoid) intake. The apparent protection conveyed by vitamin A was stronger in current smokers. The risk of bladder cancer was not related to scores of fat and measures of alcohol consumption; the risk was elevated in coffee drinkers (although there was no tendency to rise with higher consumption), but it was reduced in tea drinkers. These findings were not explainable in terms of selection, information, or confounding bias. Thus, although available information is too uncertain for any precise definition of specific (micro)nutrients related to bladder cancer risk, the confirmation that several aspects of a less-affluent diet adversely affect the risk is still of interest in terms of a better understanding of bladder carcinogenesis. 相似文献
4.
M Regallo S Scalambrino L Negri F Landoni C Mangioni 《Drugs under experimental and clinical research》1989,15(6-7):315-320
A prospective randomized study was carried out on a total of 686 patients who underwent vaginal or abdominal hysterectomy. Of these, 338 were given prophylactic cefotetan (2 g) and 348 piperacillin (2 g). Both drugs were administered as i.v. bolus 30 min before operation. Findings confirm the higher risk of infection with abdominal hysterectomy and the advantages of the long half-life cephalosporin, cefotetan. 相似文献
5.
Monica Conciatori Christopher J Stodgell Susan L Hyman Melanie O'Bara Roberto Militerni Carmela Bravaccio Simona Trillo Francesco Montecchi Cindy Schneider Raun Melmed Maurizio Elia Lori Crawford Sarah J Spence Lucianna Muscarella Vito Guarnieri Leonardo D'Agruma Alessandro Quattrone Leopoldo Zelante Daniel Rabinowitz Tiziana Pascucci Stefano Puglisi-Allegra Karl-Ludvig Reichelt Patricia M Rodier Antonio M Persico 《Neuropsychopharmacology》2004,55(4):413-419
BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference. 相似文献
6.
C Cislaghi E Negri C La Vecchia F Levi 《Revue d'épidémiologie et de santé publique》1990,38(3):237-243
A method of graphic representation of time factors in cancer mortality is presented, based on different tonalities of grey applied to the surface of the matrix defined by various age-specific rates. It is illustrated using mortality data from cancers of the mouth or pharynx, oesophagus, larynx and lung in Italian and Swiss males. Progressively more complex regression surface equations are defined, on the basis of two independent variables (age and cohort) and a dependent one (each age-specific rate). General patterns of trends were thus identified, showing important similarities in cohort and period effects, but also noticeable differences in time-related factors in mortality from various neoplasms of the upper digestive and respiratory tract. For instance, there were declines in mortality from cancers of the mouth or pharynx in the oldest age groups, whereas rates were appreciably upwards at younger and middle age, particularly in Italy. Likewise, cancers of the oesophagus and, chiefly, of the larynx were substantially increasing, on a cohort basis, in oldest Italian males. Temporal pattern for laryngeal cancer in Italy was similar to that of lung cancer, thus suggesting that (cigarette) smoking has a greater impact on this cancer site as compared with alcohol. However, it is difficult to explain, on this basis alone, the totally diverging pattern for cancer of the larynx (downwards) and of the lung (upwards) observed among older Swiss males. These examples indicate that trend surface models are a useful summary guide to illustrate and understand the general patterns of age, period and cohort effects in cancer mortality. 相似文献
7.
Oral contraceptive use and invasive cervical cancer 总被引:1,自引:0,他引:1
The relationship between oral contraceptive use and the risk of invasive cervical cancer was investigated using data from a hospital-based case-control study conducted in the greater Milan area, Northern Italy. A total of 367 women under 60 years of age with a histologically confirmed diagnosis of invasive cervical cancer was compared with a group of 323 controls admitted for a spectrum of acute conditions, non-gynaecological, hormonal or neoplastic and apparently unrelated to oral contraceptive use. Cases had used oral contraceptives more frequently than controls, the age-adjusted relative risk (RR) being 1.53 (95% confidence interval 0.99-2.36). The risk increased with duration of use: compared with never users the age-adjusted RR was 1.48 for up to two years and 1.83 for more than two years (chi 2(1) = 5.28, p = 0.02). Allowing for major identified potential confounding factors, including sexual and reproductive habits, by means of multiple logistic regression, did not explain the association (multivariate RR 1.85 for ever use, 1.05 for up to two years and 2.47 for more than two years). When the interaction between oral contraceptive use and parity or sexual habits was analysed, the effects of various factors appeared independent: the point estimate for multiparous oral contraceptive users versus nulliparous never users was 8.01. There was no consistent influence on risk of invasive cervical cancer of age at first use, whereas the RRs were slightly greater for women who had first used oral contraceptives less than ten years before or had last used them less than five years before diagnosis: these findings, however, were far from significant. 相似文献
8.
Extensive bone resorption occurring in aural cholesteatoma is responsible for the severe complications of this disease. In the area of active bone destruction, typical multinucleated osteoclasts are rarely seen, but a heavy cellular infiltrate is found. In the present study we tried to characterize the immunophenotype and the functional state of the cells infiltrating the stroma and the epithelial layer of aural cholesteatoma, using a panel of monoclonal antibodies directed against cell type specific antigens. The results were compared with normal retroauricular skin. The vast majority of cells infiltrating the stroma was bone marrow derived and consisted of T-cells and macrophages. By means of the activation markers HLA-DR and Interleukin-2 receptor an immunologically activated state of the majority of infiltrating cells in cholesteatomas was shown. The great number of activated macrophages in cholesteatomas seems to be very important in the cholesteatomatous immunological process. Because of their various immunological functions (antigen presentation to T-lymphocytes, participation in ingestion and killing of different invading microorganisms and synthesizing a great number of substances involved in host defence and inflammation) these cells play a central role in human immunological system. Langerhans cells, however, did not appear to be involved in the immune process of cholesteatoma. The characteristics of the infiltrating cell population with the great number of phagocytic cells suggest an active immune process resulting in autoaggressive bone resorption. 相似文献
9.
BACKGROUND. The relation between body mass index and acute myocardial infarction was analyzed using data from a multicentric case-control study conducted in Italy between September 1988 and June 1989 within the framework of the GISSI-2 trial. METHODS. Subjects were 916 patients with acute myocardial infarction and no history of cardiovascular disease and 1,106 controls hospitalized for acute conditions not related to known or suspected risk factors for ischaemic heart disease. RESULTS. Relative to the lowest quintile of the Quetelet Index (weight/height2) the estimated risks for subsequent quintiles were 1.2 (95% confidence intervals, (CI): 0.9 to 1.6), 1.7 (95% CI: 1.2 to 2.2), 1.8 (95% CI: 1.4 to 2.4), and 2.2 (95% CI: 1.7 to 3.0) when adjustment was made for age, sex, education, and smoking habits by means of logistic regression. The association was consistent across strata of sex, education, and smoking status, but not age. The estimated risk for subjects in the fifth quintile of the Quetelet Index relative to those in the first was 4.1 under 55 years of age, but only 1.7 between 55 and 64 years and 1.5 above age 65. CONCLUSION. The relation between body mass and myocardial infarction was explained, at least in part, by higher serum cholesterol levels and the prevalence of diabetes and hypertension among fatter subjects. This does not, however, totally eclipse a possible causal relation between body mass and risk of myocardial infarction, since these conditions are a consequence, rather than a confounder, of overweight. 相似文献
10.
F Levi C La Vecchia F Lucchini E Negri 《Rapport trimestriel de statistiques sanitaires mondiales》1992,45(1):117-164
A study was carried out to analyse trends in cancer mortality sex differentials. This study compared age-standardized sex ratio values for mortality from 18 cancers (or groups of cancers), and total cancer mortality over the period 1950-1989 in 24 European countries, for 4 age groups (all ages, 20-44 years, 45-64 years, and 65 years and over). For lung cancer and other tobacco-related neoplasms, appreciable rises in sex ratio values were observed until the late 1970s, particularly in Southern and Eastern Europe, before levelling off in recent years, particularly among the younger age groups. In the late 1980s, the range of variation in overall age-standardized sex ratios for lung cancer was between 2 and 3 in the United Kingdom and in Nordic countries, and around or over 10 in Southern Europe. In young adults, the decline in sex ratio values observed in Denmark and Sweden (unity), and in other Nordic countries and in the United Kingdom (around or below 2) reflects a levelling of lung cancer in young males and an increase in young females. This clearly indicates that young women are a priority target group for smoking control interventions in Europe. Appreciable cohort effects were also observed for stomach cancer: rises in sex ratio values were greater in, or restricted to, middle- and older age groups, whereas in the young there was some tendency towards a levelling in sex differentials. The overall sex ratio values for stomach cancer were around 2 in most areas of Europe in the late 1980s. For intestinal cancer, sex ratio values showed some tendency to rise, reaching a level of 1.3-1.7 in the late 1980s; steady rises were also registered in sex ratio values for melanoma (skin cancer), reaching 1.5-1.8 in the late 1980s in most countries. These upward trends which were minor or inconsistent at younger ages in several countries became progressively stronger with advancing age. Sex ratio values were below unity for cancers of the gallbladder and the thyroid. Sex ratio values tended to rise also for leukaemia (from 1.2-1.5 to 1.5-1.7), but showed no noticeable trend for lymphomas or myeloma. The overall sex ratio values for total cancer mortality in the 1950s were between 1.2 and 1.4 in most European countries. Thereafter, they rose appreciably in several countries, reaching 1.9 in Czechoslovakia, Italy and Poland, and 2.3 in France.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献