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1.
The aim of the study was to determine the effect of exogenous melatonin treatment on circulating prolactin levels in red deer. Melatonin was administered from 12 June 1984 (day 1) to lactating and non-lactating hinds in the feed daily at 1600 h, and to non-lactating hinds by a subcutaneous implant. Average concentrations (ng/ml) of prolactin in plasma taken serially over 15-h periods were significantly higher for untreated hinds than for melatonin-treated animals on day 15 whether lactating (66-133 v. 23-28, P less than 0.05) or non-lactating (28-174 v. 8-13, P less than 0.01), remained higher on day 36 (lactating: 41-152 v. 15-21, P less than 0.05; non-lactating: 21-50 v. 1-7, P less than 0.001) but had decreased to similar levels on day 72 (lactating: 5-24 v. 7-17; non-lactating: 2-9 v. 0-4). The advanced reduction in plasma prolactin for all melatonin-treated hinds was associated with an advanced onset of seasonal breeding activity.  相似文献   
2.
Occupational airborne allergic contact dermatitis from tylosin   总被引:2,自引:1,他引:1  
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3.
Rats selectively bred for disparate degrees of ethanol-induced depression of spontaneous locomotor activity (most affected = MA; least affected = LA) were trained on a swim task. Undrugged rats of the MA line swam significantly faster than rats of the LA line. Ethanol, 0.0–2.25 g/kg i.p., produced dose-dependent increases in swim time in rats of the 13th generation (F13). Averaged over trials, these increases were greater in LA than in MA rats and greater in males than in females, but there was no sex difference in peak impairment. Increases in swim time were uncorrelated with predrug performance. These findings were confirmed in younger F17 rats receiving 1.75 g EtOH/kg i.p. Although the lines differed in ethanol-induced impairment, F17 males of the two lines were not differentially impaired by pentobarbital (12.5–22.5 mg/kg, i.p.). The existence of task-dependent line differences in ethanol sensitivity emphasizes the nonunitary nature of ethanol-induced behavioral depression.  相似文献   
4.
This review summarizes the history and current state of the known genetic basis for soybean resistance to Soybean mosaic virus (SMV), and examines how the integration of molecular markers has been utilized in breeding for crop improvement. SVM causes yield loss and seed quality reduction in soybean based on the SMV strain and the host genotype. Understanding the molecular underpinnings of SMV–soybean interactions and the genes conferring resistance to SMV has been a focus of intense research interest for decades. Soybean reactions are classified into three main responses: resistant, necrotic, or susceptible. Significant progress has been achieved that has greatly increased the understanding of soybean germplasm diversity, differential reactions to SMV strains, genotype–strain interactions, genes/alleles conferring specific reactions, and interactions among resistance genes and alleles. Many studies that aimed to uncover the physical position of resistance genes have been published in recent decades, collectively proposing different candidate genes. The studies on SMV resistance loci revealed that the resistance genes are mainly distributed on three chromosomes. Resistance has been pyramided in various combinations for durable resistance to SMV strains. The causative genes are still elusive despite early successes in identifying resistance alleles in soybean; however, a gene at the Rsv4 locus has been well validated.  相似文献   
5.
Gregor Mendel was an Augustinian priest in the Monastery of St. Thomas in Brünn (Brno, Czech Republic) as well as a civilian employee who taught natural history and physics in the Brünn Modern School. The monastery’s secular function was to provide teachers for the public schools across Moravia. It was a cultural, educational, and artistic center with an elite core of friar-teachers with a well-stocked library and other amenities including a gourmet kitchen. It was wealthy, with far-flung holdings yielding income from agricultural productions. Mendel had failed his tryout as a parish priest and did not complete his examination for teaching certification despite 2 y of study at the University of Vienna. In addition to his teaching and religious obligations, Mendel carried out daily meteorological and astronomical observations, cared for the monastery''s fruit orchard and beehives, and tended plants in the greenhouse and small outdoor gardens. In the years 1856 to 1863, he carried out experiments on heredity of traits in garden peas regarded as revolutionary today but not widely recognized during his lifetime and until 16 y after his death. In 1868 he was elected abbot of the monastery, a significantly elevated position in the ecclesiastical and civil hierarchy. While he had hoped to be elected, and was honored to accept, he severely underestimated its administrative responsibilities and gradually had to abandon his scientific interests. The last decade of his life was marred by an ugly dispute with civil authorities over monastery taxation.  相似文献   
6.
为探讨德国肉用美利奴杂交F1代肉羊在舍饲、放牧补饲和全放牧条件下的肥育效果,进行了不同饲养方式的肥育试验。试验结果表明:舍饲组育肥体重平均为47.25kg,比放牧补饲和放牧对照组分别提高了22.60%和28.13%,差异极显著(P<0.01)。经屠宰测定和胴体分割测定:舍饲组屠宰率、净肉率为51.29%和43.19%,比补饲组和对照组分别提高4.57、8.21和4.65、7.58个百分点。舍饲组每只羊平均多盈利30~50元。  相似文献   
7.
从桑椹成熟果实、桑叶以及桑果园的土壤采样,进行桑椹果酒专用酵母的筛选,得到一株在性能上优于对照菌葡萄酒干酵母的酵母菌Y11。该菌起酵快,从第2天开始糖度大幅度下降,酒精度快速上升,发酵第4天酒精体积分数即可达到10%以上。发酵过程pH值变化趋势比较平缓,发酵结束后高级醇量符合要求。综合发酵性能及感官评定,表明该菌能代替葡萄酒干酵母用于桑椹果酒的生产。  相似文献   
8.
从自然界中分离聚乙烯醇(PVA)的降解细菌,经紫外线诱变,得到两株具有单重抗药性的突变菌株S7(Str^s,Kan^r)和K15(Str^r,Kan^s),两者对PVA的去除率分别达到52%和58%.将S7和K15作为亲本菌株进行原生质体融合,并对融合条件进行优化,融合子F4菌株对PVA去除率达到79.9%,将其培养成活性污泥后,PVA去除率可达87%,是普通活性污泥的三四倍.  相似文献   
9.
背景 颈源性耳鸣处于耳鼻喉科和康复科交界区域,临床上易被忽视,或常被误诊为神经性耳鸣。制定行而有效的颈源性耳鸣治疗方法具有重要现实意义。针灸是常用的治疗方法,但临床上关于刃针治疗颈源性耳鸣的研究较少。目的 探讨经筋理论下刃针治疗颈源性耳鸣的临床疗效。方法 选取2017年7月-2018年7月广州中医药大学顺德医院收治的60例颈源性耳鸣患者为研究对象,采用随机数字表法分为对照组与观察组,各30例。对照组予普通针刺治疗,观察组给予刃针治疗,两组均治疗15 d。观察治疗前后两组患者的临床疗效、Northwick Park颈痛量表(NPQ)评分、耳鸣致残量表(THI)评分及耳鸣严重程度评估量表(TSIS)评分。结果 治疗后,对照组痊愈4例、显效7例、有效13例、无效6例,观察组痊愈7例、显效12例、有效9例、无效2例,观察组临床疗效优于对照组,差异有统计学意义(Z=-2.084,P=0.037)。治疗前,两组患者的NPQ评分、THI评分及TSIS评分比较,差异无统计学意义(P>0.05);治疗后,观察组NPQ评分、THI评分及TSIS评分均低于对照组,差异有统计学意义(P<0.05)。结论 基于经筋理论的刃针疗法能缓解颈源性耳鸣患者的颈痛症状和耳鸣程度,疗效优于普通针刺疗法。  相似文献   
10.
目的研究4个来源甘草属植物的遗传基础,初步探讨扩增片段长度多态性(AFLP)分子标记技术在甘草品系选育中的应用。方法采用AFLP标记技术对乌拉尔甘草栽培新品系"民勤1号"、"喀什1号"、"阿克苏1号"和常规栽培品系内蒙古乌拉尔甘草进行基因组DNA多态性、指纹图谱和UPGMA聚类分析。结果从64对引物组合中筛选出了8对引物组合进行多态性分析,以多态位点百分率最高的E-AAC/M-CAG组合构建4个来源甘草的指纹图谱。UPGMA聚类分析将4个来源甘草分为4组,表现出不同的亲缘关系。结论"民勤1号"、"喀什1号"、"阿克苏1号"形成了独特的基因构成,可以作为乌拉尔甘草优良栽培新品系选育目标进行深入研究。  相似文献   
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