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91.
研究了日粮核苷酸对早期断奶小鼠肝脏基因表达的影响:选取16~17日龄健康BALB/C雄性小鼠60只,分成对照组和实验组,分别饲喂添加0、0.25%核苷酸的无核苷酸基础日粮,在实验的第2、4、10天采用差异显示技术分离小鼠肝脏中差异表达的基因。结果表明:采用6对引物分离到4条差异表达的基因片断。采用差异显示技术初步分离到4个受核苷酸影响差异表达的基因,这些片段需要做进一步的验证。  相似文献   
92.
本文研究了贮藏在0℃下黄瓜的冷害与时间的关系,测定了0℃和20℃下黄瓜中氨基酸种类、含量及其贮藏中的变化,结果表明,上述2种温度对谷氨酸、丙氨酸及总氨基酸含量的影响最大,0℃下受冷害黄瓜中丙氨酸含量及丙氨酸占总游离氨基酸的百分比要比在20℃下贮藏的高,而谷氨酸含量及其占总氨基酸含量的百分比却比20℃下的要低。  相似文献   
93.
Juvenile white sturgeon (Acipenser transmontanus, Richardson) were fed or starved for 4 weeks, and their whole body amino acid composition determined at the beginning and the end of the study. The amino acid compositions of muscle, liver, gill and gastrointestinal tract, and the free amino acids in plasma of fed and starved fish were also determined. Very little variation was observed in the amino acid compositions of all the tissues examined after starvation. However, the plasma free amino acids were significantly (P < 0.05) decreased following starvation. On the basis of the amino acid composition and nitrogen retention values of the whole fish, daily indispensable amino acid requirements for protein accretion and obligatory nitrogen losses (mg amino acid 100 g body weighr?1 day?1) were estimated. The pattern of indispensable amino acids required for each of these is different, with the pattern for protein accretion containing much higher levels of lysine, but lower levels of tryptophan and sulfur amino acids. Individual amino acid retention rates varied from 33.3% of dietary tryptophan to 80.2% for arginine. The estimated dietary indispensable amino acid pattern for young growing white sturgeon (expressed as a percentage of total indispensable amino acids plus cystine and tyrosine) is: arginine, 14.0; histidine, 6.6; isoleucine, 8.8; leucine, 12.5; lysine, 15.8; methionine (plus cystine), 6.6; phenylalanine (plus tyrosine), 15.5; threonine, 9.7; tryptophan, 0.8; and valine, 9.7.  相似文献   
94.
Objectives: To report (1) the force required on a single laryngoplasty suture to achieve optimal abduction of the left arytenoid cartilage, (2) peak forces experienced by the suture during induced swallowing and coughing, and during 24‐hour resting activity in a stall, and (3) peak forces during induced swallowing and coughing after left recurrent laryngeal nerve blockade. Study Design: Experimental study. Animals: Horses (n=8). Methods: Each laryngoplasty suture was instrumented with an E‐type buckle force transducer to measure the force required for optimal intraoperative left arytenoid cartilage abduction. This was correlated with abduction observed postoperatively. Change in suture force from baseline was measured during induced coughing and swallowing, and during normal stall activity. Results: Optimal intraoperative arytenoid abduction was achieved with a mean (±SD) force of 27.6±7.5 N. During saline‐induced swallowing and coughing mean force on the suture increased by 19.0±5.6 N (n=233 measurements; 7 horses) and 12.1±3.6 N (n=31; 4 horses), respectively. Sutures underwent increased loading a mean of 1152 times in 24 hours. No change in suture force was observed with respiratory rhythm. Conclusion: Swallowing increases laryngoplasty suture force to a greater extent than coughing.  相似文献   
95.
[目的]研究近年来乐山市中心城区越冬水鸟群落结构的变迁。[方法]于2008年1月和2014年1月分别对乐山市中心城区越冬水鸟群落结构进行了调查。[结果]伴随城市化的快速发展,乐山市中心城区“三江”水鸟的群落结构发生了明显变化,以红嘴鸥(Larus ridibundus)和崖沙燕(Riparia riparia)等为代表的中小型鸟类逐步取代大中型的鸭科(Anatidae)鸟类成为群落优势种。[结论]该研究可为评估经济活动和生态环境对乐山市中心城区水鸟群落的影响奠定基础。  相似文献   
96.
Clinical and haematological features of haemangiosarcoma in dogs   总被引:1,自引:0,他引:1  
Canine haemangiosarcoma was studied retrospectively in 31 cases recorded among 2,871 dogs presented for necropsy (1.08%). The German Shepherd breed was more frequently represented than other breeds. Affected dogs were older than 5 years (mean 9.1 years). Nineteen were males. Presenting signs often included episodic lethargy and weakness, with depression, anorexia and mucosal pallor. Spleen and lungs were the most frequently affected sites. Haematological findings in 9 dogs with splenic or hepatic haemangiosarcoma included a mild to moderate normochromic anaemia, neutrophilia, thrombocytopaenia, poikilocytosis and increased target cells. Acanthocytes occurred in 90% of cases, schizocytes in 80% and keratocytes and metarubyricytes in 70%. Fibrin split products were increased in 2 of the 3 cases in which they were measured. The changes in erythrocyte morphology are considered to be useful diagnostic features of canine haemangiosarcoma.  相似文献   
97.
The effect of resection of 75% (length measurement) of the large colon in ponies was studied. Ten ponies in good physical condition were divided into two groups: group I consisted of the six experimental ponies and group II of four control ponies. Preoperatively and postoperatively for five months, ten clinicopathological parameters were determined: body weight, venous blood pH, plasma bicarbonate, total plasma protein concentration, serum electrolyte values (sodium, potassium, chloride), and fecal osmolarity. Subjective assessment of attitude and appetite revealed no difference between the groups or within groups at any time. Resection of a major portion of the large colon did not significantly influence the clinicopathological parameters evaluated. The hematocrit of the ponies in group I did decrease during the first postoperative month and this was attributed to whole blood loss associated with the resection procedures. The results of this investigation indicated that resection of 75% of the large colon in ponies is compatible with life.  相似文献   
98.
SUMMARY The response of sheep to a recombinant multivalent footrot vaccine containing pilus antigens was examined after the administration of two doses of vaccine at Intervals ranging from 2 to 52 weeks. Agglutinating antibody titres were measured 3 weeks after the second vaccination and showed that lengthening of the interdose interval results in higher agglutinin titres. The capability of sheep to mount an increasingly strong immune response as the interval between doses is increased provides an opportunity to maximise the usefulness of vaccination by administering the first dose well before an expected footrot transmission period. This advantage of increasing the interdose interval has not been reported for traditional, whole-cell footrot vaccines, and use of the new pilus vaccine in this manner may improve prospects for disease control. Furthermore, sheep given a third dose either 6 or 12 months after their initial two-dose vaccination program achieved significantly higher titres than those elicited after the second dose, suggesting the likelihood of further improvement in disease control in successive seasons.  相似文献   
99.
Abstract. A novel disease affecting the brown-spotted grouper, Epinephelus tauvina Forskal, described here as Sleepy Grouper Disease1 (SGD), resulted in significant economic losses in some Singaporean marine net-cage farms from April to August 1992. Investigations suggested that the aetiological agent was a virus, probably introduced with imported groupers. The virus was provisionally identified as an iridovirus on morphological evidence. The disease caused extreme lethargy in affected fish with few visible external signs. Mortalities either occurred gradually over the week from onset of clinical signs, or over a shorter period and in large numbers if fish were stressed. Consistent tissue changes were seen by light microscopy in the spleen, heart and kidney of affected fish. Electron microscopy showed viral particles associated with damage to cell organelles. In an experimental infection, apparently healthy fish cohabiting with an infected fish developed similar lesions and died. The significance of SGD in grouper culture is discussed.  相似文献   
100.
The effect of inflammation on the disposition of phenylbutazone (PBZ) was investigated in Thoroughbred horses. An initial study ( n = 5) in which PBZ (8.8 mg/kg) was injected intravenously twice, 5 weeks apart, suggested that the administration of PBZ would not affect the plasma kinetics of a subsequent dose. Two other groups of horses were given PBZ at either 8.8 mg/kg ( n = 5) or 4.4 mg/kg ( n = 4). Soft tissue inflammation was then induced by the injection of Freud's adjuvant and the administration of PBZ was repeated at a dose level equivalent to, but five weeks later than, the initial dose. Inflammation did not appear to affect the plasma kinetics or the urinary excretion of PBZ and its metabolites, oxyphenbutazone (OPBZ) or hydroxyphenylbutazone (OHPBZ) when PBZ was administered at 8.8 mg/kg. However, small but significant increases ( P <0.05) in total body clearance ( CL B; 29.2 ± 3.9 vs. 43.8 ± 8.1 mL/ h-kg) and the volume of distribution, calculated by area ( V d(area); 0.18 ± 0.05 vs. 0.25 ± 0.03 L/kg) or at steady-state ( V d(SS); 0.17±0.04 vs. 0.25 ± 0.03 L/ kg), were obtained in horses after adjuvant injection, compared to controls, when PBZ was administered at 4.4 mg/kg which corresponded to relatively higher tissues concentrations and lower plasma concentrations (calculated) at the time of maximum peripheral PBZ concentration. Soft tissue inflammation also induced a significantly ( P <0.05) higher amount of OPBZ in the urine 18 h after PBZ administration but the total urinary excretion of analytes over 48 h was unchanged. These results have possible implications regarding the administration of PBZ to the horse close to race-day.  相似文献   
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