Dose effects of flaxseed and its lignan on N-methyl-N-nitrosourea-induced mammary tumorigenesis in rats

Dietary supplementation with flaxseed or its lignan secoisolariciresinol diglycoside (SDG) has reduced dimethylbenz[a]anthracene-induced mammary tumor size and number in rats. The objective of this study was to determine whether flaxseed has a dose-dependent effect on N-methyl-N-nitrosourea (MNU)-induced mammary tumor promotion and whether this effect can be attributed to its SDG. Two days after injection with MNU (50 mg/kg body wt i.p.), female Sprague-Dawley rats were fed a high-fat (20% soybean oil) AIN-93G basal diet alone (BD) or supplemented with flaxseed (2.5% F and 5% F) or SDG by gavage [SDG in 2.5% F (LSDG) and SDG in 5% F (HSDG)] for 22 weeks. Although tumors tended to be smallest in the 5% F group throughout the experimental period, flaxseed feeding did not significantly affect tumor size, multiplicity, or incidence in comparison to BD. However, there was a dose-dependent effect of SDG on tumor multiplicity. Tumor multiplicity was lowest in the HSDG group and highest in the LSDG group throughout treatment (p < 0.05), indicating that HSDG inhibited, whereas LSDG promoted, MNU-induced mammary tumor development. Tumor invasiveness and grade were decreased in all treatment groups compared with the BD (p < 0.032). Thus, although flaxseed feeding had no significant effect on tumor growth indexes, flaxseed and SDG treatment, regardless of dose, appeared to delay the progression of MNU-induced mammary tumorigenesis. Disparities between this study and previous studies on flaxseed may be related to differences in experimental design, the use and dose of a different carcinogen, and protective effects by the alpha-linolenic acid present in the BD.     

Variations in the survival probabilities of the PVC-protected red mangrove propagules: testing the encased replanting technique

The EcoEléctrica Mangrove Planting Project, a five-year voluntary effort, has the purpose of testing a recently developed mangrove planting technique at the EcoEléctrica site in Pe?uelas, Puerto Rico. The goal of the project is to provide empirical validation to promote or improve the technique to be used in recovering mangrove ecosystems in Puerto Rico and United States. The research presented herein analyzed the information collected on the first two years of the project. The proportions of remaining casings and seeds per study zone were compared using the chi-square distribution. Zone 1 had the least pipes lost while Zone 4 had the most (p < 0.05). Forty-three percent of the seeds in Zone 1 remained in the casing, while 26% remained in Zone 2 (p = 0.03). Median growth rates of seeds per study zone showed that Zone 1 had the highest median growth rates. Survival analysis described the survival experience of the seeds, and differences in survival probabilities were compared with the log-rank test. Zone 1 seeds had a better survival experience compared to Zones 2, 3 and 4 (p < 0.0001). Survival probabilities for being free of spots were over 60% during the whole study period. No significant differences were observed in the survival experience with the use-or-no use of casing extensions (p = 0.40), and the use-or-no use of nursed seeds (p = 0.26). Differences in survival probabilities might be attributed to variations in wave energy, depth or substrate conditions. This hypothesis will be evaluated in the second phase of the study.     

Health status and functional limitations in the elderly population of the University Region of Health of Puerto Rico: methodologic aspects and prevalence estimates

In order to plan the health services for the elderly population, it is necessary to quantify their health status and their functional capacity. In Puerto Rico, few epidemiological studies have been conducted regarding functional capacity and chronic diseases in the elderly population. One of the difficulties to undertake these studies is the high cost and risks to move this population for clinical exams, in addition to the methodology limitation of self-report in the elderly population. This study shows the use of logistic regression to estimate the prevalence of chronic diseases and functional capacity, when the observed data are not consisted with the planed sampling scheme. Four hundred and eighty-seven elderly persons (65 yr. and over) were interviewed in the municipalities of Canóvanas, Carolina, Loíza and Trujillo Alto in Puerto Rico, using a cross-sectional design. More than half of the elderly had visual problems (IC 95%: 54.8%, 63.8%), arthritis (IC 95%: 52.7%, 61.5%) and hypertension (IC 95%: 47.3%, 56.3%). In the case of hypertension, significant differences (p < 0.05) by sex were observed, where women reported a higher prevalence than men. One of the higher prevalences in the functional capacity status was with urine accidents. More than one-third of the population is estimated to have this problem (IC 95%: 34.7%, 43.4%). One-fourth of the population had limitations with going out for shopping (IC 95%: 23.9%, 31.9%) and using public and private transportation (IC 95%: 19.5%, 26.9%). We conclude that the applied methodology was consistent with the estimation presented in the literature and statistics from the Puerto Rico Health Department. However, it is necessary to continue assessing the design and analytical methodology, in order to undertake consistent and periodic evaluations of the elderly population.     

严重颅眶损伤的特点和救治

目的探讨严重颅眶损伤的特点和救治。方法回顾分析1990年1月～1997年12月收治的32例严重颅眶损伤患者的临床资料。结果32例严重颅眶损伤的临床特点为：脑损伤局限．意识障碍较轻,嗅神经、视审经损伤多见,脑脊液漏发生率高,颅眶畸形严重。结论应重视院前急救,尽早转送专科医院．除清除颅内血肿外,应注重视神经损伤、脑脊液漏和颅眶畸形手术处理．积极治疗并发症,有利于视神经功能的恢复,并能有效预防脑脊液漏引起的颅内感染．改善面部外观。     

几种生长因子在人表皮细胞无血清培养中的作用

目的为生长因子在烧伤创伤面的应用提供理论依据。方法采用无血清培养系统,以3H－TdR掺入法测定表皮生长因子（EGF）、牛垂体提取物（BPE）和乙醇胺（Etha）对人表皮细胞DNA合成的影响。结果EGF和BPE在无血清培养基中对培养表皮细胞DNA合成有明显的促进作用（P＜0．01）;Etha对培养表皮细胞DNA合成也有促进作用（P＜0．05）;EGF和Etha在本培养体系中具有协同作用（P＜0．05）。结论生长因子在烧伤创面的治疗中具有应用价值。     

再植肢不同时期侧支循环重建的影像学实验研究

目的研究大鼠再植肢不同时期主要动脉阻断后侧支循环重建的影象学表现.方法选用成年SD大鼠48只制成再植肢动物模型,每组随机选3只鼠做血管造影,分析、比较各再植肢不同时期侧支循环的影象学变化.结果 4天、1周组再植肢再植平面远、近侧无明显新生侧支血管生长.2、3周组侧支血管在再植平面近侧开始出现,自4周组起可见丰富的侧支血管通过再植平面,逐渐增多增粗增长并长向远侧.结论大鼠断肢再植术二周后再植平面侧支循环开始重建.此时,再植肢可逐渐依靠重建的侧支循环而成活.     

微波治疗宫颈糜烂的临床观察

目的探讨微渡与CO2激光对宫颈糜烂疗效优劣;方法用微波治疗100例,CO2激光治疗宫颈糜烂86例,疗效经u检验处理;结果微波与CO2激光治疗宫颈糜烂疗效比较u=2．20,P<0．05,微波治疗效果明显优于CO2激光治疗效果,不良反应比较,无显性差异u=0．72,P>0.05。结论微波治疗宫颈糜烂疗效好,修复快,副作用低,值得推广应用。     

原发性脑室出血的CT征象与治疗（附28例报告）

目的探讨原发性脑室出血的临床表现、脑CT征象及其与治疗的关系;方法回顾性分析28例经CT证实原发性脑室出血病人的临床表现及CT征象;结果多有头痛、呕吐等脑膜刺激征表现,无脑局灶受损体征,脑CT均示原发脑室出血;结论原发性脑室出血的诊断依靠脑CT,Ⅰ型脑室出血宜行侧脑室外引流术,预后较差,Ⅱ、Ⅵ型可行腰穿脑脊液置换术．预后较好。     

颈总动脉形态及血流动力学改变与脑梗死类型的关系

目的研究颈总动脉形态及血流动力学改变与脑梗死类型的关系。方法应用经颅彩色双功能多普勒超声检查法．测定40例脑穿通支动脉梗死、31例脑主干支动脉校死和30例正常对照者的颈总动脉管径及有或无粥样斑块等反映血管形态和收缩峰速、每分钟血流量、阻力指数等血流动力学指标。结果结果表明当颈总动脉出现粥样斑块,而无明显血流动力学改变时,易发生穿通支脑梗死;随着血流动力学,尤其是血流收缩峰速度和阻力指数等指标的异常程度加重,发生脑主干动脉梗死的危险性增大。结论颈总动脉形态及血流动力学改变与患者发生脑梗死类型密切相关。     

失能调整生命年在煤矿职业性疾病负担分析中的应用

为估计煤矿外伤性截瘫疾病负担,采用横断面抽样调查,共抽样调查全国５ 个统配矿务局的２６ 个煤矿。以煤矿外伤性截瘫的患病和死亡资料为基础,用失能调整生命年（ＤＡＬＹ） 估计煤矿外伤性截瘫疾病负担。结果表明：煤矿外伤性截瘫疾病负担为每千人口３２２５ＤＡＬＹ。各矿务局比较：铜川矿务局外伤性截瘫疾病负担最重,每千人口５４４７ ＤＡＬＹ,高于５ 个矿务局的平均水平每千人口３２２５ＤＡＬＹ。其次为阳泉、峰峰矿务局、三路安矿务局和晋城矿务局,分别为每千人口２７ ．８５ 、２６ ．６０ 、１５１０ 和１１ ．７１ＤＡＬＹ。结果提示：ＤＡＬＹ 可用于煤矿职业性疾病负担分析。各统配矿务局外伤性截瘫的ＤＡＬＹ 差异较大