市售肉蛋奶中汞残留的检测

对四川省雅安地区市售畜禽鱼肉、蛋、奶九个品种38份样品,采用冷原子吸收法进行了汞残留的检测。结果表明,鱼和鸭肉含量最高,牛奶和兔肉含量最低,其他居中。土壤和粮食中也测出汞。本文对防止汞对环境和食物的污染,加强食品中汞残留的监测提供了依据。     

Erratum

In the letter from Martin M. Barnes (3 Dec. 1976, p. 998), the first citation in reference 1 should have been J. Swarz, "Poisoning farmworkers," Environment 17 (No. 4), 26 (1975).     

Organic mercury identified as the cause of poisoning in humans and hogs

Atomic absorption spectrophotometry and neutron activation analysis showed the presence of mercury in organic extracts of seed grain and in tissues of hogs fed the contaminated grain. Mercury was also found in the urine, serum, and cerebrospinal fluid of humans who ate the contaminated pork. Mass spectral analysis confirmed the presence of organic mercury. This paper reports the first documented episode of indirect mercury poisoning in humans in the United States caused by the ingestion of contaminated meat from animals that had consumed mercury in their food supply.     

Corrections and clarifications

In the response by E. A. Finch and S. M. Goldin (5 Aug., p. 813) to the technical comment "Calcium and inositol 1,4,5-trisphosphate-induced Ca(2+) release" by L. Combettes and P. Champeil (5 Aug., p. 813), in parts B and C of figure 1 (p. 814), the insets referring to Ca concentrations were inadvertantly interchanged. The concentration for figure 1B should have been, "300 nM Ca" and that for figure 1C should have been, "10 nM Ca."     

猪肉颜色与其他肉质和胴体指标间的相关性研究

以皮特兰猪与我国地方猪种金华猪杂交的资源家系为材料,分析猪肉颜色指标与其他肉质和胴体指标之间的相关性.结果表明猪肉颜色指标间普遍存在显著的相关性,除明度系数L值与红度a值和色调角h值相关不显著外,其他猪肉颜色指标之间的相关系数都达到极显著水平(P＜0.0001);猪肉颜色与其他肉质指标和胴体指标之间也普遍存在相关性,其中较多为负相关.L值、彩度c值与眼肌pH、腿肌pH、眼肌面积、系水力呈显著的负相关(P＜0.05);a值、绿度b值与腿肌温度、眼肌面积呈显著的负相关(P＜0.05);b值还与系水力呈极显著负相关(P＜0.01);h值与眼肌温度、腿肌温度呈极显著的正相关(P＜0.01).     

池塘混养和专养条件下罗氏沼虾营养品质 比较研究

目的以罗氏沼虾为研究对象,比较分析河蟹-罗氏沼虾混养模式与传统罗氏沼虾专养模式产出的罗氏沼虾营养价值和品质变化。方法通过测定体重、体长、出肉率比较两种养殖模式下虾体形态特差异;通过测定水分、蛋白质、灰分、脂肪、矿物质、脂肪酸和氨基酸,比较虾肉营养价值变化;通过测定质构特性和呈味核苷酸比较虾肉品质变化。结果与专养的罗氏沼虾相比,混养模式下罗氏沼虾规格显著提高,但出肉率有所下降。混养的虾肉脂肪含量从(0.91±0.07) %下降为(0.59±0.05)%,差异显著(P <0.05);虾肉的钙、镁、磷、铜含量上升;脂肪酸中EPA含量从(15.59±0.66) %下降至(13.64±0.71) %;氨基酸EAAI评分略有提高,罗氏沼虾虾肉营养价值变化较小。混养的虾肉硬度显著提高;呈味核苷酸AMP和IMP含量从(78.15±1.23) g/100g和(162.90±2.67) g/100g提高至(86.96±1.87) g/100g和(175.12±3.01) g/100g,混养的虾肉品质显著提高。结论河蟹-罗氏沼虾混养池塘内产出的罗氏沼虾规格显著增加,营养成分变化不大,虾肉品质显著提高,符合消费者品味,具有优秀的市场前景。     

德宏水牛及其杂交品种分割肉的研究

试验对36￣39月龄全放牧饲养的15头德宏、摩本、尼本水牛进行了胴体分割肉测定研究,试验根据水牛品种不同分为3个处理组。试验结果显示尼本水牛与德宏水牛相比胴体重、净肉重、优质肉重均有显著提高,差异显著。尤其表现在嫩肩肉、腰肉、臀肉、膝圆、大米龙、小米龙、腱子肉这几块分割肉上。摩本水牛与德宏水牛相比胴体重、净肉重、优质肉重有显著提高,但分割肉块在重量上无显著差异。尼本水牛与摩本水牛的分割肉块重无显著差异。用尼里、摩拉与德宏水牛杂交后,提高了德宏水牛的产肉性能。     

β～肾上腺能兴奋剂对不同日粮蛋白质、蛋氨酸水平下肉鸭生长及胴体品质的影响

用121只天府肉鸭,在蛋白质水平为15％、17％(添加0、0.21％蛋氨酸)和15％日粮中分别添加0、0.5、1ppm苯甲醇胺进行饲喂,测定21至42日龄鸭生产性能和胴体品质,探讨了不同饲粮条件下添加苯甲醇胺的效果。结果表明,添加1ppm苯甲醇胺鸭只的增重、42日龄屠宰率、胸腿肌率及鸭体蛋白、水分含量在17％,15％CP和0.21％met组显著高于0ppm对照(P<0.05—0.01),而腹脂率肌胃重及体脂含量显著降低(P<0.05—0.01)而20％cp及0％met组添加苯甲醇胺对增重、体成分无显著影响。     

杜洛克、长白、大约克猪生长和肉用性状的杂交参数估计

采用Dickerson(1973)模型,用加权最小二乘分析估计了杜洛克（杜）、长白（长）、大约克（大）猪的杂交参数。结果表明,3个亲本品种在生长和肉用性状上存在明显的遗传差异。生长和肉用性状的母本遗传效应较小（失水率、大理石纹等级、贮存损失例外）。胴体体尺性状个体杂优值较小,但日增重和料肉比的个体杂优估值高。母本杂优效应对于日增重、料肉比、胴体比例、失水率、肉色等级、贮存损失和背膘厚具有一定的重要性。正反交差异表明,大约克×长白比长白×大约克更利于生长和肉用性能提高。     

Erratum

In the Technical Comment "Trans-activator gene of HTLV-II: Interpretation" by W. C. Greene et al. (27 Feb., p. 1073), the third-from-the-last sentence should have read, "In addition, using Jurkat or other T-cell lines, Inoue and colleagues (2) and Maruyama et al. (3) have described activation of both the IL-2 receptor and IL-2 genes by the tat-I gene isolated from HTLV-I, which shares similar structural and functional properties with the tat-II gene." Reference 3 should have been to M. Maruyama et al., cell 48,343(1987).     

Erratum

In the Special Report ;;Science careers' edited by Constance Holden (24 May), Michigan State University should have been given as the institution that granted a Ph.D. to Christopher Uhl (p. 1123) and the University of Illinois as the institution that granted an M.S. and a Ph.D. to Alfred Cho (p. 1124).     

巴什拜羊肉不同部位的品质特性分析

[目的]研究巴什拜羊不同分割部位肉的理化性质,为建立羊肉品质评价标准的提供参考.[方法]选用6～9月龄的巴什拜羊17只,取宰后24 h的肩肌、臀肌和背最长肌,对其常规营养成分、解冻滴水损失、熟肉率、pH值、系水力、肉色、剪切力、胶原蛋白及溶解度、结缔组织滤渣和肌原纤维断裂指数(MFI)进行测定.[结果]在不同部位间,肌肉的粗蛋白、不溶性胶原蛋白、pH值、肉色度值和系水力有极显著差异(P＜0.01);总胶原蛋白含量、MFI、肉色L*值和b*值、剪切力有显著差异(P＜0.05).肌肉的剪切力与熟肉率、胶原蛋白含量、胶原蛋白溶解度、结缔组织滤渣含量和MFI之间有较高的相关性;肉色几乎与各项肉质指标呈正相关,系水力呈负相关;pH值与粗脂肪、系水力呈正相关,与解冻滴水损失、水分和胶原蛋白含量呈负相关.[结论]部位因素对羊肉的粗蛋白、胶原蛋白含量、MFI、pH值、肉色、系水力和剪切力的影响较大.背最长肌的租蛋白、胶原蛋白含量、色度值、熟肉率和MFI较高,水分含量和剪切力较低,具有肉色鲜艳、肉质嫩等特点.不同部位羊肉理化性质与品质特性之间存在着复杂的内在联系.     

Corrections and clarifications

In table 1 (p. 1124) of the article "Prehistoric extinction of Pacific island birds: Biodiversity meets zooarchaeology," by David W. Steadman (24 Feb., p. 1123), the column headings for modern and fossil record were reversed; under each island name, the letters "F M" should have appeared.     

某体温计厂附近土壤汞含量及影响因素研究

采集体温计厂周围300m内17个点的土壤作为样品,分析其全汞含量,并研究汞含量的影响因素。结果表明：距汞车间300m范围内土壤汞含量均超过背景值,土壤均表现出不同程度的汞污染。在体温计厂Hg车间排气口和排水口外的土壤属于极严重污染（Hg含量为8．65～19．77m昏／kg）,在100m范围内为重污染区（Hg含量为1．48～2．75mg／kg）,在100～300m范围内为中等污染区（Hg含量为0．15～0．95mg／kg）。分别为背景值的169、24、8倍。随着采样点到汞车间排气口距离的增加,土壤中汞的含量随之减少。土壤汞含量主要受当地主风向的影响。另外,在排气口和排水口附近往往汞含量极高。有机质含量对土壤中汞的含量有一定影响。     

Effects of organic chromium supplementation to finishing lambs diet on growth performance,carcass characteristics and meat quality

The objective of this study was to evaluate supplemental organic chromium(Cr) to finishing lambs on growth performance, carcass characteristics, and meat quality. Eighteen Suffolk lambs(age(4.5±0.2) mon;(25.8±3.6) kg body weight(BW)) were randomly assigned to three levels of supplemental organic Cr(0.0, 0.2 and 0.4 mg kg–1 dry matter(DM)) in a complete random design. Growth performance was evaluated for 70 d, and then lambs were slaughtered to study carcass characteristics and chemical composition of meat. Orthogonal contrasts were performed(contrast one-average level 0.2 ppm Cr vs. average level 0.4 ppm Cr; contrast two-level 0 vs. average levels(0.2+0.4) ppm Cr). Orthogonal polynomials were used to estimate the linear and quadratic effects of Cr concentrations. Growth and carcass performance were not affected by supplemental organic Cr. Muscle conformation and leg perimeter linearly increased(P0.05) as organic Cr level increased in the diet. Kidney fat decreased linearly(P0.05) as supplemental Cr increased. In Longissimus dorsi(LD), the ash content decreased linearly, and shear force(kg cm–2) increased(P0.05) as organic Cr level increased in the diet. It is concluded that organic Cr did not affect growth performance, but it improved positively the muscle conformation, reduced kidney fat, whereas in LD there was an increment in shear force in finishing carcass lambs.     

Rockefeller braces for Baltimore

In the article "Rockefeller braces for Baltimore" by Barbara J. Culliton (News & Comment, 12 Jan., p. 148), the pictures of David Baltimore and Joshua Lederberg were incorrectly credited. The credit for the Baltimore picture should have read, "M. Lampert, Boton." The credit for the Lederberg picture should have read, "Rockefeller University."     

皖南花猪资源现状及存在问题与对策

受外来高产畜禽品种强烈冲击,我国地方畜禽品种数量逐渐减少和消失的问题日渐突出。皖南花猪是安徽省著名地方品种之一,目前主要分布在黄山以南、新安江上游的皖南地区,1973年入选《中国猪种志》。皖南花猪具有性成熟早,母性好,繁殖率高,哺育率高,瘦肉率高、肉品质好、耐粗饲、抗病抗逆性强等优点。该文阐述了皖南花猪资源和保护利用现状,指出存在的主要问题,并提出若干对策与措施。     

大米汞污染与摄食大米甲基汞暴露研究进展

本文汇总了环境与大米汞污染的来源、汞与甲基汞对人体的健康危害、水稻对甲基汞的吸收与累积、包括大米在内的食品中汞的含量与形态分析方法、全球大米汞污染的现状,以及人群摄食大米的甲基汞暴露方面的研究进展。我国贵州和东南亚汞矿开采地区产出的大米存在严重的汞污染,且大米为当地居民的主要粮食,摄食大米给当地居民带来了严重的甲基汞暴露健康风险。未来有必要在全球更广泛地开展大米汞污染与相应的人群摄食暴露健康风险评估工作,并加强水稻对环境中汞的吸收、转运和累积机制以及这一系列过程中汞形态转化方面的研究。     

Erratum

In the announcement of the Gordon Research Conferences by A. M. Cruickshank (4 Mar., p. 1095), under the heading "Fertilization and the Activation of Development" (p. 1108), four listings under the topic "Gamete recognition and binding II" on 2 August were incorrectly printed. They should have read, "Michael G. O'Rand, (subject to be announced); Bayard Storey, ;Reactions between sperm and zona pallucida leading to fertilization in the mouse'; Bonnie S. Dunbar, (subject to be announced); Paul Wasserman, ;Egg surface glycoproteins that regulate mammalian fertilization.' " Under the heading "Hormone Action" (p. 1112), two listings under the topic "Prolactin" on 9 August were incorrectly printed, and one was omitted. They should have read, "Henry Friesen, ;Prolactin receptors'; Paul Kelly, ;Second messenger for prolactin'; Jeffrey Rosen, ;Prolactin regulation of casein genes.' "     

Corrections and clarifications

In the article "Molecular basis of mammalian sexual determination: Activation of Müllerian inhibiting substance gene expression by SRY" by C. M. Haqq et al. (2 Dec., p. 1494), parts B and C of figure 1 were inadvertently interchanged. In figure 3A, the third, fourth, and fifth lanes should have been labeled "A(7) --> T," "A(7) -->C," and "A(7) --> G," respectively. In figure 5, the factor labeled "SRIF's" should have been labeled "SRYIF's."