促黄体素释放激素（LRH）抗原对公雏免疫去势效果的研究

制备促黄体素释放激素（ＬＲＮ）抗原乳剂，给１０日龄公雏注射后，每周称体重，测鸡冠厚、高、长度，第２０周屠宰，称们体重及睾丸重。试验结果表明，ＬＲＨ抗原无论加入弗氏佐剂或氢氧（也铝佐剂，只要达到一定注射剂量（首次量１０μｇ／只，二次量加倍），就可产生明显的免疫去势效果，即鸡冠及睾九生长变慢，试验组与对照组比较差异十分显著（Ｐ＜０．０１）；体重增长加快，试验组与对照组比较，在第４、８、２０周平均体重和宰后胴体重差异十分显著（Ｐ＜０．０１）或显著（Ｐ＜０．０５）。而ＬＲＨ首次注射剂量为５μｇ／只的试验组与对照组比较，上述各项指标均无显著差异（Ｐ＞０．０５）。     

Androgen-concentrating cells in the midbrain of a songbird

Androgen-concentrating cells were found in the midbrain of the chaffinch Fringilla coelebs by autoradiography using tritiated testosterone. Labeled cells were localized primarily in the nucleus intercollicularis, an area from which vocalizations can be electrically stimulated in birds. These autoradiographic results suggest that the nucleus intercollicularis is a site in the action of androgens on avian vocal behavior.     

Progesterone-dependent messenger RNA: heterospecific activity in vivo

The action of progesterone in mediating the synthesis of avidin by the chick oviduct can be simulated by the intraoviductal instillation of nitrocellulose-trapped RNA from hormonally prepared chick or pigeon oviduct. Similarly, the pigeon oviduct synthesizes avidin in response to chick oviduct RNA. Thus, a heterospecific transfer of hormonal stimulation, through the transfer of progesterone-induced RNA, is demonstrated. The biological activity is lost after digestion by pancreatic ribonuclease. The 50-fold purification achieved by nitrocellulose chromatography of the total RNA preparation suggests that the activity resides in a messenger RNA fraction.     

Angiogenesis induced by degradation products of hyaluronic acid

Partial degradation products of sodium hyaluronate produced by the action of testicular hyaluronidase induced an angiogenic response (formation of new blood vessels) on the chick chorioallantoic membrane. Neither macromolecular hyaluronate nor exhaustively digested material had any angiogenic potential. Fractionation of the digestion products established that the activity was restricted to hyaluronate fragments between 4 and 25 disaccharides in length.     

Nervous regulation of conditioned hyperglycemia to nociceptive stimulation

2-Acetyl-7-oxo-1, 2, 3, 4, 4a, 4b, 5, 6, 7, 9, 10, lOa-dodecahydrophenanthrene possesses androgenic activity when applied directly to the chick's comb. This action is in addition to the antiandrogenic activity previously reported for this compound. This is the first demonstration of androgenic activity by a compound not possessing the steroid nucleus.     

United time-frequency spectroscopy for dynamics and global structure

Ultrashort laser pulses have thus far been used in two distinct modes. In the time domain, the pulses have allowed probing and manipulation of dynamics on a subpicosecond time scale. More recently, phase stabilization has produced optical frequency combs with absolute frequency reference across a broad bandwidth. Here we combine these two applications in a spectroscopic study of rubidium atoms. A wide-bandwidth, phase-stabilized femtosecond laser is used to monitor the real-time dynamic evolution of population transfer. Coherent pulse accumulation and quantum interference effects are observed and well modeled by theory. At the same time, the narrow linewidth of individual comb lines permits a precise and efficient determination of the global energy-level structure, providing a direct connection among the optical, terahertz, and radio-frequency domains. The mechanical action of the optical frequency comb on the atomic sample is explored and controlled, leading to precision spectroscopy with an appreciable reduction in systematic errors.     

巢础成型系统的设计

笔者介绍了一种巢础成型系统,主要由熔蜡设备、制片系统、压花设备、装箱设备等组成,从原材料熔化到巢础装箱全部采用自动化生产,能够改变巢础生产的落后状况,提高巢础的生产效率和产品质量。     

中蜂生产巢蜜关键技术研究

在介绍巢蜜概念及其历史的基础上,对中蜂生产巢蜜的优势进行了分析,并提出了适合我国推广的中蜂生产巢蜜的关键技术。     

单复冠基因对白羽丝毛乌骨鸡体尺性状与精液品质的影响

为观察单、复冠基因对白羽丝毛乌骨鸡的体尺性状以及精液品质的影响,寻找体尺性状和精液品质间的相互关系,对44只55周龄单、复冠白羽丝毛乌骨鸡种公鸡的体尺与精液品质进行了测定,结果表明:单冠乌鸡的体尺均值均大于复冠乌鸡;单、复冠乌鸡间精液品质无明显差异;单、复冠乌鸡的体尺性状与精液品质间的相关性均无达到显著水平;单冠乌鸡的精液品质与体尺性状间的相关性多为负相关。故在乌鸡的选育中,不仅要重视单冠基因在体尺性状方面的明显优势,还应该特别注意单、复冠乌鸡在精液品质与体尺性状相关性方面的差别。     

蜂群温度变化规律的研究

利用蜂箱内多点温度检测仪,直接准确地检测蜂箱内的实际温度,研究蜂群中边脾、中间脾和同一张脾上不同点温度在一天中的变化以及与环境温度的相关性。结果表明:子脾上的温度受环境温度影响不明显,空脾明显;子脾的中部、下部受环境温度影响不明显,而前部、后部、上部随环境温度的上升而上升,随环境温度下降而下降。     

亮热厉螨越冬虫态与场所

亮热厉螨(Trapilaelaps clareue)的越冬问题,在养蜂界说法不一,通常认为在西方蜜蜂群内的封盖子脾上越冬。经初步观察试验,其越冬场所以封盖子脾为主,南方温暖地区也可在群外的空脾和花粉脾中越冬,还可在某些动植物上渡过短促的越冬期。越冬虫态是成螨。     

残膜捡拾机机架及梳齿的仿真设计与试验

机架和梳齿是残膜捡拾机的主要承载部件,为了研究机架的振动特性,利用有限元分析软件对机架进行模态分析,结果表明,机架的固有频率和外激频率相差较大,可以有效避免共振的发生。为了研究梳齿设计的合理性,利用离散元分析软件进行梳齿应力应变的正交试验,并利用DesignExpert软件进行曲面响应分析,结果表明,梳齿作业时运动速度越大,入土深度越大,入土角度越小,所受的土壤阻力越大。以耦合的方式分析得到梳齿的受力云图和变形量,结果表明,梳齿齿尖处受力最大,变形最大,其最大等效应力为183.4 MPa,最大变形量为20.949 mm,经校核梳齿的设计符合要求。样机捡拾率的田间试验结果高达85%以上,满足捡拾要求。     

Studies on 4-keto-L-proline

The administration of ketoproline to chick embryos resulted in an increase in the free hydroxyproline. This phenomenon is explained by the inhibitory action of ketoproline on the catabolism of hydroxyproline as well as by the conversion of the former to the latter. Ketoproline was found to be reduced to hydroxyproline by the supernatant fraction of rat-kidney homogenate in the presence of a reduced pyridine nucleotide.     

中、大型轧花机棉子梳的有限元分析与改进设计

棉子梳是轧花机中有效控制毛头率的部件,中、大型轧花机的棉子梳较长,在棉子卷压力和子棉卷转动对棉子梳所产生的切向力作用下,中间部分一段长度范围变形较大,导致轧花机整个幅宽方向毛头率不一致,不但损失了衣分,而且直接影响了皮棉质量。针对上述问题,利用ANSYS Workbench有限元分析软件对棉子梳进行静力学分析,通过建模、加载、计算及后处理,获得棉子梳的变形分布情况,经与实际轧花过程中的棉子梳变形结果比对是一致的。基于此对棉子梳提出改进方案,并通过试验对比分析改进前后的毛头率。结果表明,改进后的棉子梳有效解决了大、中型轧花机的毛头率不一致问题。     

丝毛乌骨鸡冠型类别与生产性能的关系分析

对引入甘肃兰州的同日龄４７周龄９８羽单冠、１４２羽复冠乌骨鸡进行了为期１８７天的饲养对比试验，对不同冠型鸡的产蛋量、蛋重、采食量、体重、体尺进行了测定，并对群体中单复冠的遗传规律进行了分析。表明乌骨鸡单冠比例与其他鸡品种的冠型遗传规律相一致；单冠鸡各项生产指标与生活力均优于复冠鸡。     

中性红染色法检测人参皂苷及其衍生物对CEF增殖的影响

[目的]为体外研制人参皂苷及其衍生物的抗MDV作用机制提供理论依据。[方法]采用中性红染料吸收法,检测了人参皂苷及其衍生物对鸡胚成纤维细胞（CEF）体外培养中增殖活性的影响。[结果]各药物的促增殖作用不完全相同,低毒性的药物促增殖作用更明显。从药物对CEF细胞的不同作用时间点来看,以72h的OD值和正常对照的差异最大,在24h和正常对照组差异不显著。[结论]人参皂苷及其衍生物在中、低浓度能够促进CEF细胞的增殖,且药物作用具有时间依赖性。     

鸡冠类型对白羽丝毛乌骨鸡体尺性状的影响

对44只55周龄单、复冠白羽丝毛乌骨鸡种公鸡的体尺进行测定,结果表明:单冠乌鸡的体重、体斜长、胸骨长、胫长、胫围、骨盆宽等6个性状间存在显著正相关;复冠乌鸡的体重与胫长、胸宽,胸宽与骨盆宽间存在显著正相关,其余均为不显著正相关,且单冠乌鸡的体尺均大于复冠乌鸡。     

单冠、玫瑰冠、豆冠、胡桃冠鸡屠宰性能及肌肉品质

选用单冠、玫瑰冠、豆冠、胡桃冠4种不同冠型鸡各150只为研究对象,采用统一的常规饲喂方法至120日龄时,各随机抽取50只,公母各半,进行屠宰测定.总体评价玫瑰冠鸡肉用性能最好,有一定生产价值和推广前景,在今后的试验和育种工作中,应尽量提高其活体质量以增强食用性能;胡桃冠公鸡活体质量显著高于其他冠型,但屠宰率和肉品质较差,有进一步改善其肉用价值的潜力.     

Induction by soluble factors of organized axial structures in chick epiblasts

Inductive action of soluble factors was tested on isolated chick epiblasts. An assay was developed wherein conditioned medium derived from the Xenopus XTC cell line induced the formation of a full-length notochord and rows of bilaterally symmetric somites. Basic fibroblast growth factor, epidermal growth factor, retinoic acid, and transforming growth factor type B1 and B2 were not capable of inducing axial structures. Thus, soluble factors can elicit the development of polarity stored in the epiblast and behave as true morphogens since they can induce the formation of the organized complex structures that constitute the embryonic axis.     

Inductive interactions between human dermis and chick chorionic epithelium

In a study of specificity in mesenchymal-epithelial interactions, human embryonic dermis has been recombined with chick chorionic epithelium and cultured for 7 days on a host chick chorioallantoic membrane. Dermis from the sole of the foot or palm of the hand induces chick chorionic epithelium to form an epidermis that resembles chick rather than human epidermis. Chick epithelium, though it has the capacity to respond to a human dermal stimulus, is limited to forming chick-type tissue. The human dermis was modified in its turn by culture in combination with chick epithelium.