中草药对断奶仔猪生长性能影响的Meta分析

利用Meta分析方法对已发表的中草药在断奶仔猪阶段应用试验研究进行评价,为断奶仔猪保健治疗提供参考。通过计算机检索CNKI、Wanfang Data、Science Direct、Web of Science、VIP数据库,全面收集中草药在断奶仔猪阶段添加的对照试验。采用Cochrane协作网推荐的Review Manager 5.3软件对各效应指标进行Meta分析。共纳入27篇文献,1 870头仔猪,试验组935头,对照组935头,试验组均采用中药治疗,对照组采用金霉素、硫酸黏杆菌素、硫酸黏杆菌素+杆菌肽锌等抗生素治疗。结果显示：中药组对日增重的影响优于整体抗生素组[SMD=1.22,95% CI（0.69~1.75）,P<0.01],但与金霉素组统计学无差异（P>0.05）;中药组日采食量优于整体抗生素组[SMD=0.77,95% CI（0.34~1.20）,P<0.01],但与金霉素组作用相当（P=0.05）;中药组和抗生素组的料重比差异不显著[SMD=-0.35,95% CI（-0.78~0.09）,P=0.12>0.05],但显著优于硫酸黏杆菌素和金霉素亚组（P<0.01）;中药组的腹泻率极显著低于抗生素组{SMD=-1.77,95% CI[-2.52~（-1.01）],P<0.01},但与硫酸黏杆菌素+杆菌肽锌组相比,效果相当（P>0.05）。仔猪断奶阶段添加中草药,在日增重、日采食量、腹泻率指标上优于抗生素组,即中药在断奶仔猪阶段研究具有重要潜力。     

中国苜蓿产量及水分利用效率对种植年限响应的Meta分析

为探究种植年限对苜蓿产量和水分利用效率(WUE)的影响,确定不同生境下苜蓿最适宜的种植年限,本研究以中国为研究区域,以3~5年生苜蓿为对照,通过检索文献整合已发表的相关田间试验数据,截至2019年5月共获得80篇文献、1496组苜蓿产量和220组WUE试验数据,将数据按照年降水量(<200 mm,200~400 mm,400~800 mm和≥800 mm)、施肥措施(施肥和不施肥)、水分管理(灌溉和雨养)进行分组,采用整合分析方法(Meta-analysis,包括异质性检验、综合效应量计算、发表偏倚检验和亚组分析),系统探究了种植年限对苜蓿产量和水分利用效率的时空效应与影响因素,并定量分析了环境因子与不同种植年限苜蓿产量以及WUE的关系。本研究结果表明,随种植年限的延长草产量和WUE呈现先升后降的趋势,3~5龄为苜蓿盛产期,而6~8龄苜蓿WUE最高。苜蓿种植年限受环境因素及水肥措施影响,干旱、半干旱区,苜蓿最适宜的种植年限为3~5年;半湿润区,苜蓿最适宜的种植年限可延长至6~8年,但湿润区由于温湿度过高,使得苜蓿最适宜的种植年限缩短至3~5年。施肥可适当延长苜蓿种植年限,但灌溉并不能有效延长苜蓿种植年限。     

Association between residential greenness and birth weight: Systematic review and meta-analysis

Birth weight is extensively investigated as an outcome of interacting with greenery in mothers’ living environment, because it is one of the major causes for neonatal and infant mortality, as well as a correlate of some adverse effects in childhood and beyond. Conversely, in modern urban-ecological systems the access to greenery is limited. The aim of this study was to answer the question whether green spaces and generally greenery in the living environment of pregnant women are associated with the birth weight of their infants and what the direction of that effect is. MEDLINE, EMBASE and the Internet were searched for relevant publications in English and Spanish. Eight studies were identified and included in the analyses (total n = 214 940). We report quality effects meta-analyses based on correlation and standardized regression coefficients as estimates of effect size. Neighbourhood greenness within 100-m buffer was weakly and positively associated with birth weight. The pooled correlation coefficient was 0.049 (95% CI: 0.039, 0.059) and the pooled standardized regression coefficient was 0.001 (95% CI: ?0.001, 0.003). There was, however, considerable heterogeneity between the studies. Using more sensitive measures for greenness and taking into account green space functionality and quality, adjusting for environmental exposures, and assessing individual attitudes towards nature, might yield clearer picture, higher statistical power and more precise results in future research. Our findings endorse the emphasis put on urban forestry and landscape management as closely related to public health and propose a more naturalistic, humanitarian and person-centered approach in future studies.     

中国集约高产农田生态健康评价方法及指标体系初探

如何科学评价目前中国粮食主产区高产农田的生态健康现状与问题,为制定科学合理的对策,促进中国粮食主产区农业可持续健康发展、保障国家粮食安全是当务之急。目前关于农田生态系统健康评价从土壤-作物-环境三大子系统综合考虑构建评价指标体系的研究很少,没有比较完善的、为大家公认的关于农田生态健康状况评价的指标体系。采用总体分析法,查阅统计了国内外关于农田生态健康评价研究的相关指标。在此基础上,为了使评价指标更加切合中国三大平原粮食主产区高产农田土壤、作物以及环境的健康问题,采用专家问卷调查法,最终初步确定了中国农田生态健康评价指标体系,每个区域的评价体系都有22个指标,三大平原指标之间有所区别,充分体现了整体的一致性和区域的特殊性,使得指标体系更具实用性和针对性,可为该领域的研究与决策提供科学参考。     

土壤微生物对增温响应的Meta分析

通过对35例2009-2015年初发表的增温控制试验的96组数据进行Meta分析,研究了土壤微生物对增温的响应模式,结果表明:增温提高了土壤微生物碳(1.4%)、土壤微生物氮(1.7%)和土壤真菌量(3.7%),降低了土壤细菌量(-1.9%);土壤微生物碳的增温响应与试验地年平均降水量和增温幅度显著相关;土壤微生物氮的变化受试验地年均温、年均降水量及增温幅度的影响.     

Changes in agronomic traits of sunflower hybrids over 20 years of breeding in central Argentina

This paper applies linear mixed model and pattern analyses to 122 on-farm trials of commercial and near-commercial sunflower (Helianthus annuus L.) hybrids grown over 15 years in 32 locations of central Argentina to determine the contributions of change in characteristics of germplasm pools to increases in oil yield. The ‘Relative Peak Performance’ (best linear unbiased predictors, BLUPs) of 49 hybrids released for the conventional market between 1983 and 2005 showed genetic gains of 11.9 kg ha⁻¹ year⁻¹, 0.19% year⁻¹ and 16.1 kg ha⁻¹ year⁻¹ for oil yield, grain-oil concentration and grain yield, respectively. Oil yield improvement was consistent across three market segments and a biplot of genotype-by-attribute BLUPs summarised 20 years of breeding to demonstrate how the merging of two germplasm pools of differing maturity, achene type and grain-oil concentration resulted in step-wise improvements in grain yield and grain-oil concentration and a move toward an intermediate maturity. The analysis of general combining ability within a breeding program shows that the female and male germplasm pools were improved in different ways over time. On the female side, much of this improvement was to encompass different combinations of the determining traits of oil yield, while on the male side the improvement was more linear in terms of exploitation of genotypic variance for oil yield per se.     

Harvest impacts on soil carbon storage in temperate forests

Forest soil carbon (C) storage is a significant component of the global C cycle, and is important for sustaining forest productivity. Although forest management may have substantial impacts on soil C storage, experimental data from forest harvesting studies have not been synthesized recently. To quantify the effects of harvesting on soil C, and to identify sources of variation in soil C responses to harvest, we used meta-analysis to test a database of 432 soil C response ratios drawn from temperate forest harvest studies around the world. Harvesting reduced soil C by an average of 8 ± 3% (95% CI), although numerous sources of variation mediated this significant, overall effect. In particular, we found that C concentrations and C pool sizes responded differently to harvesting, and forest floors were more likely to lose C than mineral soils. Harvesting caused forest floor C storage to decline by a remarkably consistent 30 ± 6%, but losses were significantly smaller in coniferous/mixed stands (−20%) than hardwoods (−36%). Mineral soils showed no significant, overall change in C storage due to harvest, and variation among mineral soils was best explained by soil taxonomy. Alfisols and Spodosols exhibited no significant changes, and Inceptisols and Ultisols lost mineral soil C (−13% and −7%, respectively). However, these C losses were neither permanent nor unavoidable. Controls on variation within orders were not consistent, but included species composition, time, and sampling depth. Temporal patterns and soil C budgets suggest that forest floor C losses probably have a lesser impact on total soil C storage on Alfisols, Inceptisols, and Ultisols than on Spodosols, which store proportionately large amounts of C in forest floors with long C recovery times (50–70 years). Mineral soil C losses on Inceptisols and Ultisols indicate that these orders are vulnerable to significant harvest-induced changes in total soil C storage, but alternative residue management and site preparation techniques, and the passage of time, may mitigate or negate these losses. Key findings of this analysis, including the dependence of forest floor and mineral soil C storage changes on species composition and soil taxonomic order, suggest that further primary research may make it possible to create predictive maps of forest harvesting effects on soil C storage.     

中西医结合治疗新生儿脓疱疮临床疗效的Meta分析

目的 通过对相关文献进行Meta分析,系统评价中西医结合治疗新生儿脓疱疮的临床疗效。方法 检索PubMed、Medline、中国期刊全文数据库、维普期刊数据库、中国知网和万方数据库,检索中西医结合治疗新生儿脓疱疮的随机对照研究（RCT）,由两名评价者独立提取资料并进行方法学质量评估,数据分析采用RevMan 5.3软件进行统计分析。结果 共纳入16个RCT,Meta分析结果显示,中西医结合治疗新生儿脓疱疮总有效率Meta分析结果为：[OR=5.59（95% CI：3.81,8.20）,P<0.01],提示中西医结合治疗新生儿脓疱疮总有效率优于单纯西医治疗;中西医结合治疗新生儿脓疱疮显效率Meta分析结果为：[OR=3.57（95% CI：2.41,5.29）,P<0.01],提示中西医结合治疗新生儿脓疱疮显效率高于单纯西医治疗;脓疱症状消失时间Meta分析结果显示：[MD=-1.64（95% CI：-1.88,-1.40）,P<0.01],提示中西医结合治疗新生儿脓疱疮较单纯西医治疗的脓疱消失所需时间更短。结论 中西医结合治疗新生儿脓疱疮的临床疗效较单纯西医治疗临床疗效更好,且痊愈所需时间更少,临床值得推广。     

中医治疗肾虚型排卵障碍性不孕症的Meta分析

目的 评价中医治疗肾虚型排卵障碍性不孕症的疗效。方法 通过电子计算机检索中国期刊全文数据库（CNKI）、万方数据库、中国生物医学文献数据库（CBM）及维普（VIP）资讯数据库,查阅从2001年1月1日至2017年5月31日之间国内发表的肾虚型排卵障碍性不孕症相关的临床随机对照试验（RCT）文献,同时对检索的文献进行筛选。使用Jadad评分量表对符合入选标准的随机对照研究进行质量评分,提取有效数据,并使用软件Revman 5.3版进行分析,采用优势比（OR）作为效应合并指标。结果 共纳入21个RCT,1999例病例。纳入RCT的同质性较好,Meta分析结果提示中医治疗肾虚型排卵障碍性不孕症疗效显著,可明显提高妊娠率。漏斗图提示纳入研究可能存在发表偏倚风险。结论 中医治疗肾虚型排卵障碍性不孕症疗效显著。但还需要一些大样本、高质量的RCT临床试验设计来支持此结论。