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991.
OBJECTIVE: To investigate the internal validity of a food-frequency questionnaire (FFQ) developed for a case-control study of prostate cancer in southeast China. DESIGN: A comprehensive questionnaire comprising a quantitative FFQ and a short food habit questionnaire (SFHQ) was developed and modified from previous cancer and nutritional studies. The Goldberg formula (ratio of energy intake (EI) to basal metabolic rate (BMR), EI/BMR) was used to assess the validity of the FFQ by making comparisons with physical activity levels. Physical activity levels were measured by the estimated total metabolic equivalents (MET) and the ratio of energy expenditure (EE) to BMR (EE/BMR). Correlation analyses were undertaken to compare the SFHQ variables with those of the quantitative FFQ. SETTING: Hangzhou, Zhejiang Province, China. SUBJECTS: A total of 404 men over 45 years old with or without prostate cancer were recruited from eight hospitals. RESULTS: The partial correlation coefficients, controlling for age and family history of prostate cancer, were moderate to high (P<0.05) for preserved foods intake, fat consumption and tea drinking variables between the SFHQ and the quantitative FFQ. The average EI/BMR was 1.72, with 76% of subjects exceeding the Goldberg cut-off value of 1.35. Apart from weight, BMI, EE/BMR and MET, there were no significant differences in characteristics between low (<1.35) and normal EI/BMR groups. CONCLUSIONS: The FFQ is demonstrated to be a valid instrument to measure energy and food intake for elderly men in southeast China. 相似文献
992.
Hamaide AJ Grand JG Farnir F Le Couls G Snaps FR Balligand MH Verstegen JP 《American journal of veterinary research》2006,67(5):901-908
OBJECTIVE: To compare the urodynamic and morphologic effects of the administration of estriol alone and in combination with phenylpropanolamine on the lower portion of the urogenital tract in female dogs. ANIMALS: 3 sexually intact and 3 spayed female Beagles without urinary incontinence. PROCEDURE: Dogs received estriol (2 mg, PO) once daily for 7 days followed by estriol (2 mg, PO) and phenylpropanolamine (1.5 mg/kg, PO) once daily for 7 days. Urethral pressure profilometry, diuresis cystometry, and vaginourethrography were performed before treatment (day 0) and at days 7 and 14. The maximum urethral pressure (MUP) and closure pressure (MUCP), urethral functional and anatomic profile lengths, integrated pressure (IP), plateau, distance before MUP, maximum meatus pressure, threshold pressure, threshold volume, compliance, urethral length, and vaginal length and width were measured. RESULTS: Before treatment, no urodynamic differences were observed between the 2 groups; however, vaginal length and width were significantly shorter in spayed dogs. Compared with day 0 values, estriol treatment significantly increased MUP, MUCP, and IP values at day 7, but at day 14, this effect decreased despite phenylpropanolamine administration. No morphologic changes from baseline were detected after either treatment in any dog. CONCLUSIONS AND CLINICAL RELEVANCE: Data suggest that estriol mainly acts on the urethral sphincter mechanism by increasing urethral resistance in sexually intact and spayed female dogs without urinary incontinence. Administration of estriol and phenylpropanolamine did not increase the urethral resistance more than estriol alone. The urodynamic effects of estriol in female dogs with urinary incontinence remain to be elucidated. 相似文献
993.
Dechant JE Nieto JE Le Jeune SS 《Journal of the American Veterinary Medical Association》2006,229(2):253-258
OBJECTIVE: To evaluate clinical findings, underlying causes, and short-term outcome associated with hemoperitoneum in horses. DESIGN: Retrospective case series. ANIMALS: 67 horses with hemoperitoneum. PROCEDURES: Medical records of horses with hemo-peritoneum (excluding postoperative abdominal hemorrhage) from 1989 through 2004 were analyzed. Information obtained included history, signalment, physical examination findings, diagnostic test results, and short-term outcome. RESULTS: Breed distribution was 28 Thoroughbreds, 13 Arabians, 10 Quarter Horses, 5 Warmbloods, 3 Appaloosas, and 1 each of 8 other breeds. There were 40 mares, 23 geldings, and 4 stallions. Median age was 12 years (range, 1 month to 40 years). Signs of abdominal discomfort were the primary complaint in 79% of horses. Clinical findings included shock (60%) and pale mucous membranes (60%). Median heart rate was 76 beats/min (range, 30 to 216 beats/min), median respiratory rate was 30 breaths/min (range, 8 to 92 breaths/min), median Hct was 31% (range, 10.5% to 73.0%), and total protein concentration was 5.8 g/dL (range, 3.3 to 8.7 g/dL). Cause of hemoperitoneum was attributed to trauma (25.4%), neoplasia (17.9%), uterine artery rupture (13.4%), mesenteric injury (11.9%), disseminated intravascular coagulopathy (6.0%), other causes (3.0%), and idiopathic causes (22.4%). Fifty-one percent of horses survived to hospital discharge, 37% were euthanized, and 12% died. Poor short-term outcome was significantly associated with high respiratory rate and certain underlying causes. CONCLUSIONS AND CLINICAL RELEVANCE: Hemoperitoneum is an infrequent but important cause of abdominal discomfort in horses. Predominant underlying causes were trauma, neoplasia, and idiopathic causes. Identification of underlying cause is important because of its association with outcome. 相似文献
994.
种植密度和氮用量对烟叶光合特性和产量质量的影响 总被引:8,自引:0,他引:8
在豫西半干旱地区洛宁采用密度和施氮量2因素裂区设计,研究了不同种植密度和氮用量对豫西地区烟叶光合有效辐射、光合特性和产量质量的影响.结果表明:(1)随着氮肥和密度的增加,烟株能截获更多的光合有效辐射.随着施氮量的增加烤烟净光合速率增加.高密度和高施肥量会导致烟叶气孔导度变小.(2)从烟叶产量上看,在相同的密度下,烟叶的产量随着施肥量的增加而增加,产量以D3N4处理最高,达3 162 kg/hm2;种植密度对烟叶产量的影响较大,在相同施肥水平下以D3密度平均产量最高,但D3与D2密度除N4施肥水平外产量差异不显著.从产值上分析,在相同施肥水平下以D2密度产值较高,D2N2和D2N4产值分别达到42 148.5元/hm2和42 454.5元/hm2,上等烟比例分别为32.2%和32.8%,烟叶均价以D2N2处理最高,达14.9元/kg.(3)综合分析,在豫西烟区,种植密度以D2密度(16 500株/hm2),氮肥施用量以N2水平(60 kg/hm2)为宜. 相似文献
995.
运用非参数Malmquist指数法测算了我国2000~2009年旅行社业生产率的变动趋势,并从技术进步和技术效率两个方面对全要素生产率变化特征进行分析。结果表明:近10年我国旅行社业全要素生产率增速较慢,年均增长仅0.1%,其主要来源于技术进步;辽宁等13个省份的旅行社业全要素生产率正向增长,但全要素生产率增长的来源不同;旅行社全要素生产率区域差异较大,呈现出东部、中部、西部依次递增的趋势。 相似文献
996.
指数施肥对栓皮栎容器苗生长和氮积累的影响 总被引:9,自引:0,他引:9
以栓皮栎(Quercus variabilis Blume)容器苗为研究对象,通过设置6个施肥量,研究苗木生长和氮积累对指数施肥的响应.结果表明:随施肥量的增大,苗高、地径、茎生物量均无显著变化;根系、整株生物量则先增大后减小,施肥量为75、125 mg/株时,苗木生物量趋于最大,而施肥量增至150 mg/株时,苗木生物量显著下降.施肥量由25增至75 mg/株时,茎氮质量分数由0.88%提高至1.05%,继续增大施肥量,茎氮质量分数趋于稳定;根系、整株氮质量分数则随施肥量的增大持续增加.施肥量由25增至125 mg/株,茎、根、整株氮质量逐渐增大;施肥量为125 mg/株时,苗木的整株氮质量较25mg/株的苗木提高了51.4%;施肥量增大至150 mg/株,茎、根、整株氮质量均下降.栓皮栎容器苗充足施肥量、最优施肥量分别为75、125 mg/株,施肥量超过150 mg/株时,苗木受到毒害. 相似文献
997.
为给发挥各菌株降解苯酚及其之间的协同降解作用提供一定理论依据,测定了4株苯酚降解菌邻苯二酚-2,3-双加氧酶(C23O)的最适温度和pH,同时测定了十六烷基三甲基溴化铵(CTAB)对酶活的影响.结果表明,4株菌C23O酶最适温度均在35℃左右,在高于50℃后酶活都明显下降,SW、AW、UW株菌的C23O酶具有较宽的热稳定性范围(10~40℃).4株菌C23O酶最佳pH值都在7.0~8.0,在各自最佳pH条件下,UW的C23O酶活最高.CTAB可以显著提高SW、AW、ZW3株菌的C23O酶活,利用CTAB改变细胞膜的通透性影响细胞的C23O酶活的测定,进一步反映出细胞内C23O酶催化活性和酶促反应特点. 相似文献
998.
999.
矿产资源开发生态补偿机制探讨 总被引:1,自引:0,他引:1
矿产资源开发生态补偿机制是建立我国生态补偿机制的核心内容之一,研究矿产开发过程中引起的生态破坏和环境污染,对解决生态补偿在矿产资源开发方面的一系列问题,具有重要的理论价值和现实指导意义。在系统总结我国矿产资源生态补偿现状及问题的基础上,结合国内已有的矿产资源补偿经验,提出了我国矿产资源开发生态补偿的框架,在法律法规、政策制度体系和评价机制等方面提出了对策建议,并对今后的研究重点进行了展望。 相似文献
1000.