Cytogenetic studies in rats of cyclohexylamine, a metabolite of cyclamate

Cyclohexylamine, the major known metabolite of cyclamate, was tested in vivo for possible cytogenetic effects. In rats injected with this metabolite, there was a direct relation between dose concentration and percentage of spermatogonial and bone marrow cells showing chromosomal breaks. Single chromatid breaks predominated with infrequent exchange figures.     

Dulcin and saccharin taste in squirrel monkeys, rats, and men

In a taste-preference comparison of sweetening agents, men reacted positively to two nonnutritive sweeteners, dulcin and sodium saccharin; rats preferred only saccharin and squirrel monkeys, only dulcin.     

Granulocytopenia and anemia in rats fed diets of low case in content

Severe granulocytopenia and anemia were developed uniformly in rats fed protein-free diets. Casein (18 per cent) prevented these dyscrasias, but crystalline L. casei factor ("folic acid") did not prevent them. In the correction of granulocytopenia in rats fed protein-free diets, L. casei factor alone was only slightly effective, diets of higher casein content (18 or 30 per cent) were ineffective under the experimental conditions described. However, L. casei factor combined with an 18-per cent casein-containing diet or L. casei factor combined with a mixture of purified amino acids were found to be highly effective in correcting the granulocytopenia.     

Polydipsia elicited by the synergistic action of a saccharin and glucose solution

Rats consume significantly more of a solution combining saccharin and glucose than equivalent solutions of these substances presented in separate bottles. Fluid consumption may exceed body weight. Experiments helping to delineate the basis of this synergistic action are presented.     

高效液相色谱法测定乳饮料和果汁饮料中的安赛蜜和糖精钠

建立了测定乳饮料中安赛蜜和糖精钠高效液相色谱法。乳饮料和果汁饮料中的蛋白质经亚铁氰化钾和硫酸锌沉淀,过滤液经中性氧化铝柱净化,应用光电二极管阵列(PDA)检测器在230 nm波长处测定。结果该方法的加标回收率为86.6%~92.7%,相对标准偏差为2.8%~4.2%。     

Effects of cellulase and xylanase enzymes mixed with increasing doses ofSalix babylonicaextract onin vitrorumengas production kinetics of a mixture of corn silage with concentrate

Anin vitro gas production (GP) technique was used to investigate the effects of combining different doses ofSalix babylonicaextract (SB) with exogenous ifbrolytic enzymes (EZ) based on xylanase (X) and...     

Immunological studies on urinary bladder tumors of rats and mice

Human neoplasms derived from the same tissue have been previously shown to have tumor associated antigens characterizing that tissue type. Evidence is now presented for the existence of analogous antigens common to both rat bladder papillomas and carcinomas, and for antigens common to mouse bladder carcinomas. Rats immunized with syngeneic urinary bladder papillomas, then challenged with a methylcholanthrene pellet inserted into the bladder, develop (4 to 6 months later) fewer primary bladder tumors than rats immunized with normal bladder tissue.     

旱稻与玉米间作高产高效栽培技术

用旱稻277和农大108玉米进行间作试验,结果其土地当量比LER=1 587,666 7m2总产量达664 10kg,比单作旱稻、玉米分别增产234 90kg和256 60kg,增产率分别达35 37%和38 64%。其高产高效栽培技术措施主要有:选择适宜品种,建立合理的畦宽、带比,适期早播,合理密植,加强肥水管理等。     

Effects of cellulase and xylanase enzymes mixed with increasing doses of Salix babylonica extract on in vitro rumen gas production kinetics of a mixture of corn silage with concentrate

An in vitro gas production(GP) technique was used to investigate the effects of combining different doses of Salix babylonica extract(SB) with exogenous fibrolytic enzymes(EZ) based on xylanase(X) and cellulase(C), or their mixture(XC; 1:1 v/v) on in vitro fermentation characteristics of a total mixed ration of corn silage and concentrate mixture(50:50, w/w) as substrate. Four levels of SB(0, 0.6, 1.2 and 1.8 m L g–1 dry matter(DM)) and four supplemental styles of EZ(1 μL g–1 DM; control(no enzymes), X, C and XC(1:1, v/v) were used in a 4×4 factorial arrangement. In vitro GP(m L g–1 DM) were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant p H was determined, and then filtered to determine dry matter degradability(DMD). Fermentation parameters, such as the 24 h gas yield(GY24), in vitro organic matter digestibility(OMD), metabolizable energy(ME), short chain fatty acid concentrations(SCFA), and microbial crude protein production(MCP) were also estimated. Results indicated that there was a SB?EZ interaction(P0.0001) for the asymptotic gas production(b), the rate of gas production(c), GP from 6 to 72 h, GP2(P=0.0095), and GP4(P=0.02). The SB and different combination of enzymes supplementation influenced(P0.001) in vitro GP parameters after 12 h of incubation; the highest doses of SB(i.e., 1.8 m L g–1 DM), in the absence of any EZ, quadratically increased(P0.05) the initial delay before GP begins(L) and GP at different incubation times, with lowering b(quadratic effect, P0.0001) and c(quadratic effect, P0.0001; linear effect, P=0.0018). The GP was the lowest(P0.05) when the highest SB level was combined with cellulose. There were SB?EZ interactions(P0.001) for OMD, ME, the partitioning factor at 72 h of incubation(PF72), GY24, SCFA, MCP(P=0.0143), and p H(P=0.0008). The OMD, ME, GY24 and SCFA with supp lementation of SB extract at 1.8 m L g–1 DM were higher(P0.001) than the other treatments, however,PF72 was lower(quadratic effect, P=0.0194) than the other levels. Both C and X had no effect(P0.05) on OMD, p H, ME, GY24, SCFA and MP. The combination of SB with EZ increased(P0.001) OMD, ME, SCFA, PF72 and GP24, whereas there was no impact on p H. It could be concluded that addition of SB extract, C, and X effectively improved the in vitro rumen fermentation, and the combination of enzyme with SB extract at the level of 1.2 m L g–1 was more effective than the other treatments.     

高钼条件下日粮不同铜硫水平对绵羊铜代谢及粗料消化能力的影响

选用 4只安装有永久性瘤胃瘘管的 4月龄杂交一代 (无角陶赛特×小尾寒羊 )羯羊 ,采用拉丁方设计 ,研究 4种铜添加水平 ( 0 ,6 ,12和 18mg·kg-1)和 4种硫添加水平 ( 0 ,0 0 5 % ,0 10 %和 0 15 % )在高钼 ( 12 5 5mg·kg-1)条件下对绵羊铜代谢的影响。所用铜源为碱式氯化铜 ,硫为硫酸钠 ,钼为钼酸钠。结果表明 :随着日粮中碱式氯化铜添加水平的提高 ,绵羊血浆中的铜水平显著升高 (P <0 0 5 ) ,三氯乙酸 (TCA)可溶解铜水平也显著提高(P <0 0 1) ,而TCA不溶性铜、血浆铜蓝蛋白 (Cp)和铜锌超氧化物歧化酶 (CuZn SOD)活性则无显著变化 ;随着硫添加水平的升高 ,TCA溶解铜显著下降 (P <0 0 5 ) ,TCA不溶铜显著提高 (P <0 0 1) ,血浆铜、Cp和CuZn SOD活性变化不明显 ;日粮中添加不同水平的铜和硫对铜的表观消化率、羊草干物质消失率及中性洗涤纤维 (NDF)消失率没有显著影响。结果说明碱式氯化铜是绵羊比较理想的无机饲料铜源。     

高效液相色谱法测定牛奶中苯甲酸、山梨酸和糖精钠

建立了采用高效液相色谱法同时测定牛奶中苯甲酸、山梨酸和糖精钠的分析方法,牛奶样品经水提取、离心后直接进样,于230 nm处检测,外标法定性、定量。结果表明:苯甲酸、山梨酸和糖精钠在15 min内能得到较好的分离,检出限分别为0.06、0.07、0.08 mg/kg,样品加标平均回收率在90%～105%之间。     

高脂饮食对大鼠动脉血管张力的影响

目的：观察高脂饮食大鼠动脉血管张力的改变及内源性ＮＯ、ＰＧＩ２的作用。方法：ＳＤ大鼠１６只分为高脂饮食组和对照组,喂养５周后测定血清血脂浓度和胸主动脉环对云甲肾上腺素（ＮＥ,１０＾－８￣１０＾－４ｍｍｏｌ／Ｌ）、乙酰胆碱（ＡＣｈ,１０＾－８￣１０＾－４ｍｍｏｌ／Ｌ）的反应。结果：与对照组比较,高脂饮食组ＴＣ、ＬＤＬ明显升高（Ｐ〈０．０１和Ｐ〈０．０５）;胸主动脉环对ＮＥ或ＡＣｈ的反应明显减弱（Ｐ〈     

复方巴戟天合剂对大鼠激素性股骨头 缺血性坏死的组织学研究

目的 探讨复方巴戟天合剂对激素性股骨头缺血性坏死大鼠股骨头的组织学影响、方法SD大白鼠72 只,随机分成正常组、模型组、对照组、治疗组,每组18只〔建立大鼠激素性股骨头缺血性坏死模型,对照组、治疗组 每口给药1次,于实验后第4,8,12周分3批处死动物,取股骨头空骨陷窝、成骨细胞、破骨细胞及胶原面积进行统 计学分析〔结果空骨陷窝率模型组与正常组差异有统计学意义(P<0.01) ,治疗组与对照组较模型组差异有统计学意 义}P<0.01);治疗组与对照组成骨细胞计数较模型组差异有统计学意义}P<0.01),破骨细胞计数较模型组差异有统计 学意义(P<0.01);治疗组与对照组胶原面积百分比与模型组比较差异有统计学意义}P<0.01)〔结论复方巴戟天合剂 对激素性股骨头缺血性坏死有明显的预防和治疗作用、     

转基因抗草苷膦大豆对大鼠生理代谢的影响及外源基因水平转移研究

为了分析转抗草甘膦转基因大豆对大鼠生理代谢水平的影响及其内源和外源基因遗传转移的情况，选用32只SD大鼠，随机分成2组，分别饲喂含30％转基因抗草苷膦豆粕和含30％非转基因豆粕的大鼠配合饲料，连续饲喂30d。试验结果表明，与对照组相比，试验组大鼠体重，血清中尿素氮（SUN）、葡萄糖、天冬氨酸转氨酶（CPT）和血清总胆固醇均无显著差异（P〉0．05）。同时，利用定性PER方法检测试验大鼠的血液、肌肉、肝脏、胰脏、肾脏、胃及肠道内容物中的转基因豆粕内源基因和外源基因。结果表明，在用含转基因豆粕的饲料饲喂的大鼠胃、肠道内容物中发现了转基因豆粕的内源基闲和外源基因片段，而在其血液及各组织器官中则没有发现，说明短期内转基因豆粕的内源和外源基因在大鼠体内没有发生遗传转移。     

辛·吡乳油对大蒜根蛆的防治效果

辛·吡乳油(地蛆灵)是由吡虫啉和辛硫磷复配的高效、低毒、广谱、无公害新型内吸性强的杀虫剂.地蛆灵是河南省农业科学院植物保护研究所通过对国内外数百种防治作物害虫的新药剂进行对比和筛选试验,并就吡虫啉、辛硫磷为活性成分的不同含量、不同配比进行大量试验研发的产品.     

华南地区优质高产水稻品种(组合)的适应性研究

【目的】筛选出适合于华南地区种植的水稻品种(组合)直接用于生产,或作为育种材料间接利用。【方法】采用完全随机试验设计,2019年早季在广东省珠海市对5个优质高产水稻品种(组合)‘华航48’、‘粳籼优0405’、‘粳籼优0505’、‘软华优1179’和‘软华优6100’进行了示范种植试验,考察了产量性状及其构成因素和外观品质性状,对照为优质稻‘美香占2号’。【结果】5个参试材料均属于大粒高产类型,单穴有效穗数均不到22,低于对照‘美香占2号’(24);单穗实粒数超过117粒、千粒质量大于20 g,均显著大于对照(对照分别为85.8粒和17.9 g);单穴粒质量大于47.3 g,比对照增产28%以上。5个参试材料外观品质性状均稍逊于对照,表现为粒长9.7 mm、粒宽2.5 mm、粒长/粒宽3.8、粒投影周长20.5 mm和粒投影面积16.8 mm2。相关分析结果表明,单穗实粒数、千粒质量、粒宽、粒投影面积与产量呈显著正相关;粒长、粒长/粒宽、粒投影周长与产量呈显著负相关,进一步证实了单穗实粒数与千粒质量的增产作用,也反映了外观品质与产量之间的矛盾。【结论】‘华航48’、‘软华优1179’和‘软华优6100’在华南地区早季表现优异,可直接推广应用;‘粳籼优0405’和‘粳籼优0505’适合于产量目标的生产,或作为高产优质育种的中间材料。