摘要：以香菇9608#菌株为试材,在单因素试验基础上,采用Box-Behnken响应面设计法优化香菇发酵液中硒多糖提取工艺。结果表明:富硒香菇发酵液中提取工艺硒多糖最佳醇沉时间为15.45h、乙醇浓度82.30%、pH 7.95。在此条件下,富硒香菇发酵液中硒多糖产量达到3.23g·L^(-1),香菇发酵液中硒多糖硒含量87.67μg·g^(-1)。利用Box-Behnken响应面设计法得到的富硒香菇发酵液中硒多糖提取工艺参数,可为工业化生产提供必要的技术支持。

摘要：临床试验设计和分析中常常包括影响疾病结果的非处理因素 ,这些因素被统称为协变量。对处理效应的评价 ,若不合理考虑协变量的影响 ,常常会导致结论的偏倚乃至错误。因此 ,在临床试验中要审慎地对待这一问题 ,在评价处理效应时应该考虑用协变量对其进行适当的调整 ,以达到处理效应的正确评价。试验设计阶段的协变量调整称为“事先调整” ,常用的方法有分层法、动态分配最小化法等。试验分析阶段的协变量调整称为“事后调整”,常用的方法有分层检验法、回归模型法等。通过协变量调整 ,一方面阐明病人特征在处理组间的不均衡并没有影响到处理效应的正确评价 ,提高临床试验结果的可信度 ;另外 ,协变量调整方法的合理运用还可提高统计效能。本文对处理效应评价协变量调整涉及的概念、方法、步骤等进行介绍和探讨 ,尤其强调了应用中的一些统计学事项。

摘要：文章从堆肥和活性污泥中分离得到一株能高效降解氨氮的菌株DNF2。对分离菌株进行形态观察,革兰氏染色以及16SrRNA基因序列分析,经鉴定为粪产碱杆菌(Alcaligenesfaecalis ***)。在单因素实验的基础上应用响应面法对氨氮降解菌株DNF2降解条件进行方法设计、优化并验证降解方案,以提高其降解氨氮的能力。得到优化后的降解条件如下:温度为34.3℃,pH值为7.63,接种微生物浓度为4.60%。此条件下菌株对氨氮浓度降解的理论值可达到92.54%,验证实验的平均浓度为92.05%,比优化之前提高了12.85%。根据优化后的最佳条件,将菌株DFN2接种到沼液废水中,96 h可将416.23 mg·L-1氨氮降解至2.41 mg·L-1,降解效率为99.42%。

摘要：Objective: The purpose of this study was to identify the gestational age with the lowest morbidity and mortality rates for twin pregnancies that reach term. Study design: A retrospective cohort study carried out with 60,443 twin pairs from the United States(1995-1997). Analysis was restricted to pregnancies that had reached at least 37 weeks of gestation; groups were created on the basis of the gestational ages of 37, 38, 39, and ≥40 weeks. The incidence of death and morbidity were calculated; multiple logistic regression models were used to estimate the independent effect of gestational age for twin A and B. Results: The neonatal mortality rate increased significantly after 40 weeks of gestation(twin A: odds ratio, 3.47 [95%CI, 2.29, 5.38]; twin B, odds ratio, 2.52 [95%CI, 1.75, 3.67]). There was also an increased risk of neonatal morbidity in the ≥40 weeks of gestation group for twin A and B(Apgar score, ≤3; odds ratio, 1.88 [95%CI, 1.18, 3.02], 1.74 [95%CI, 1.21, 2.52], respectively). There was a decreased risk of assisted ventilation in the 38 and 39 weeks of gestation group for twin A(odds ratio, 0.86 [95%CI, 0.77, 0.97], odds ratio, 0.83 [95%CI, 0.72, 0.95], respectively) and a decreased risk in the 39 and ≥40 weeks of gestation groups for twin B(assisted ventilation: odds ratio, 0.83 [95%CI, 0.73, 0.93], odds ratio, 0.81 [95%CI, 0.72, 0.92], respectively). Conclusion: This study suggests that the optimal date of delivery for twins should be< 40 weeks of gestation; there was no compelling evidence for delivering at< 38 weeks of gestation.

摘要：目的识别乳腺癌存活的妇女及其后的妊娠,以确定妊娠率(比例)、处理、乳腺癌预后、以及初次妊娠的结局。设计人群为基础的描述性研究,病例来源于西澳大利亚数据连锁系统,并通过对医疗表格进行回顾分析进一步确认。补充资料来自于医院及门诊记录。地点西澳大利亚,1982—2003年。对象年龄<45岁,确诊乳腺癌后妊娠的妇女。主要结局评估指标妊娠结局及妊娠率,生存情况,从诊断到妊娠的时间。结果 62名(54%)妇女在诊断为乳腺癌后2年内妊娠。其中,29例人工流产,27例活产,6例自然流产。采用比例风险回归模型分析继发妊娠与总生存时间改善的相关性(风险比0.59,95%可信区间0.37～0.95)。将该模型按从诊断乳腺癌至继发妊娠的时间进行分层,发现诊断至少24个月后的继发妊娠与总生存率的改善相关(0.48,0.27～0.83),而在确诊6个月后妊娠的妇女中这种保护作用并不显著。结论我们的研究不支持目前推荐绝经前诊断乳腺癌的妇女在试图妊娠前应等待两年的医疗建议。这一建议可能适用于那些正在接受治疗、或在诊断时患有全身性疾病的妇女。但对于那些病灶局限的妇女,在完成治疗6个月后的早期妊娠不一定降低生存。

摘要：Objective: The purpose of this study was to identify factors that predict a decision to interrupt a pregnancy in which there are fetal anomalies in the second trimester. Study design: The New Jersey Fetal Abnormalities Registry prospectively recruits and collects information on pregnancies (≥15 weeks of gestation)-from New Jersey residents in whom a fetal structural anomaly has been suspected by maternal-fetal medicine specialists. Enrolled pregnancies that have major fetal structural abnormalities identified from 15 to 23 weeks of gestation were included. Outcomes were classified as either elective interruption or a natural pregnancy course, which might include a spontaneous fetal death or live birth. Predictors of elective interruption of pregnancy were examined with univariable and multivariable logistic regression analyses. Results: Of the 97 cases, 33%of the women (n = 32) interrupted the pregnancy. Significant variables in the regression model that were associated with a decision to interrupt a pregnancy were earlier identification of fetal anomalies (19.0 ±2 weeks of gestation vs 20.5 ±2 weeks of gestation; P=.003), the presence of multiple anomalies (78% 25/32 vs 52% 33/63 ; P = .01 , and a presumption of lethality (56% 18/32 vs 14% 9/65 ; P = .0001). These variables corresponded to an odds ratio for pregnancy interruption of 4.2 (95%CI, 1.0, 17.0) for multiple anomalies, 0.8 (95%CI, 0.7, 1.0) for each week of advancing gestational age, and 36.1 (95%CI, 2.9, 450.7) for presumed lethal abnormalities. Conclusion: Early diagnosis, the identification of multiple abnormalities, and an assessment of likely lethality of fetal anomalies are important factors for the optimization of parental autonomy in deciding pregnancy management.

摘要：背景:前列腺癌根治术标本的手术切缘阳性(positive surgical margins,PSMs)为辅助放疗常用的指标,同时可用来衡量手术的质量。然而,PSMs和前列腺癌特异性死亡率(prostate cancer-specific mortality,CSM)之间的关系尚不清楚。目的:通过调整固定和随时间变化的参数分析PSMs与CSM之间的关联。设计。