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81.
对6头试验公鹿用假台鹿采精,采精前对特制的假阴道以药用凡士林为滑润剂,注水充气,温度为40℃±1℃,以适宜的压力和滑润度,将其安装在人工制做的假台鹿内。拨赶公鹿于采精场诱其爬跨。结果,试验的6头公鹿中有4头能够采精,共22头次,射精量平均每头次1.54ml,精子密度为18.6—37亿/ml,精子活力在0.8以上。93年每头次生产细管冻精106.25支(425支/4头次),是同年电刺激采精法平均64.4支/头次(902支/14头次)的1.65倍,此法既能采到质量高的精液,又比电采法省工、省时、省力、安全,是一种理想的马鹿采精方法。  相似文献   
82.
The major nematode pests of cultivated plants in Greece include root-knot nematodes Meloidogyne spp. (in almost all plants except citrus), cyst-forming nematodes Globodera rostochiensis, G. pallida (in potato), Heterodera avenae (in cereals), Ditylenchus dipsaci (in vegetables and ornamental plants) and Tylenchulus semipenetrans (in citrus). Based on observations made on samples examined at Benaki Phytopathological Institute, it was confirmed that serious infestation of new kiwi orchards with Meloidogyne spp. originated from seedlings infested at the nursery. Also the wide distribution of the nematode Tylenchulus semipenetrans in citrus orchards was mainly attributed to infested seedlings. The above observations led us, in 1985, to the decision to study the nematological fauna of nurseries in Greece.  相似文献   
83.
Seventeen lion heads were examined. Their arteries were injected with colored supervinyl-chloride (dissolved in acetone) after which the heads were macerated biologically. The rete mirabile of the maxillary artery was located extracranially and was formed by numerous arteries that arose from the dorsal and medial surfaces of the maxillary artery. The rete released branches (rami retis) which entered the cranial cavity through the orbital fissure where they anastomosed with the intracranial segment of the internal carotid artery. The extracranial portion of the internal carotid was found to be obliterated. Some other arteries leaving the rete anastomosed with the internal ophthalmic artery before it entered the optic canal. The following further arteries left the rete: A. ethmoidalis externa, A. ophthalmica externa, rami musculares and ramus pterygoideus. The rete mirabile of the maxillary artery in the lion provides the principal source of the blood for the brain; it also supplies the orbit.  相似文献   
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Ovine-derived fibroblasts were used to validate an insulin-like growth factor I (IGF-I) membrane-receptor binding assay system. Competitive binding using fibroblasts revealed that half-maximal inhibition of 125I-IGF-I binding by IGF-I was 2.3 nM. SDS-polyacrylamide gel electrophoresis analysis of specific protein-associated 125I-IGF-I was consistent with the migration of 125I-IGF-I-labeled Type I IGF receptor alpha-subunits at Mr 133,000 daltons. Further, the efficiency of two cell solubilization methods was examined and time-dependent binding equilibrium was determined for the membrane assay system. Satellite cell-derived myotubes were subsequently isolated from primary satellite cell cultures established from the semimembranosus muscles of high and low efficiency-of-gain (EOG) Targhee rams, and IGF-I receptor dynamics were measured. A membrane competitive binding study revealed that half-maximal inhibition of 125I-IGF-I binding was achieved by 1-ng IGF-I for low, and 10-ng IGF-I for high, EOG myotube membrane preparations. Kd values were similar between the high EOG (4.78 nM) and low EOG (2.95 nM) groups; however, receptor concentrations (Bmax) appeared to differ between groups. High EOG membrane receptor Bmax was 3.88 pmole/micrograms protein (19.87 pmole/micrograms DNA), whereas low EOG membrane receptor Bmax was 1.22 pmole/micrograms protein (9.28 pmole/micrograms DNA). These preliminary findings support the hypothesis that genetic selection for EOG results in altered satellite cell responsiveness to IGF-I.  相似文献   
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87.
Thyme ( Thymus vulgaris L.) plants were spaced at 15, 30 or 45 cm distances in a clay-loamy soil. They received different levels of nitrogen and phosphorus, besides a constant level of potassium. The results showed, that the wider spacing promoted the growth and production of herb and oil per plant, however dense cultivation significantly increased the yields of herb and oil per unit area. In all cases, the applied fertilization treatments significantly increased the productivity per unit area. Dense cultivation accompanied with higher levels of fertilization proved to be very usefull. The essential oil content was not influenced by either the plant spacing or fertilization treatments applied in this study.  相似文献   
88.
Abstract The abundances of Aeromonas salmonicida subsp. salmonicida in the water and in the surface microlayer was studied during the initial phase of a cohabitant infection experiment with Atlantic salmon, Salmo salar L., smolt. Aeromonas salmonicida was detected in the water samples only until the intraperitoneally infected smolt were dead and had been removed. In the lipid rich surface microlayer, A. salmonicida was detected in high concentrations from the day of the first fish mortality and throughout the rest of the experiment. The significance of the high cell surface hydrophobicity is discussed as a possible reason for enrichment of A. salmonicida at the air-water interface.  相似文献   
89.
Four mares fed a low fiber, high soluble carbohydrate diet were used in a crossover design to evaluate the effects of dietary sodium bicarbonate (NaHCO3) supplementation during daily low-intensity submaximal working conditions. Mares were fed the diet at 1.7 times the maintenance energy requirement for mature horses at work. The horses tolerated the diet well and had no clinical abnormalities. Resting venous blood bicarbonate (HCO3), standard HCO3, and base excess (BE) concentrations significantly (P less than 0.05) increased with NaHCO3 supplementation, but no significant changes in resting venous blood pH or carbon dioxide tension (PCO2) were recorded. Venous blood HCO3, standard HCO3, BE, hemoglobin, and heart rate were significantly (P less than 0.05) increased and plasma lactate concentration was significantly (P less than 0.05) decreased in the control horses and in the horses given the NaHCO3 supplement during low-intensity submaximal exercise. There were no significant changes in venous blood pH, PCO2, or plasma protein concentration with exercise. Venous blood HCO3, standard HCO3, and BE concentrations were significantly (P less than 0.05) greater during submaximal exercise in horses given the NaHCO3 supplement. There were no significant differences in plasma lactate or total protein concentrations, blood pH, PCO2, or hemoglobin concentration between the 2 groups during exercise.  相似文献   
90.
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