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1.
安普霉素对仔猪内分泌的调控作用及血液生化指示的影响 总被引:4,自引:0,他引:4
采用单因子试验设计 ,28日龄大长北三元杂交断奶仔猪72头随机分为3组 ,研究饲料中添加不同剂量的安普霉素 (0、20、90mg/kg)对仔猪内分泌的调控作用及血液生化指标的影响。试验期为4周。结果表明 :仔猪日粮中添加90mg/kg的安普霉素可促进机体与生长有关的内分泌活动 ,提高内源激素 (生长激素、胰岛素、甲状腺激素T3)水平 (P<0.05),从而促进肌肉蛋白沉积 ;并具有显著降低血液中氨、尿素氮含量和提高血糖水平的作用 (P<0.05) ,表明安普霉素对仔猪具有增加氮沉积 ,促进蛋白质合成、抑制蛋白质分解的作用 相似文献
2.
Precise localization of the needle tip during CT-guided percutaneous biopsy is considered to be a key element of a successful procedure. To ensure accuracy, the true needle tip must be differentiated from a false or simulated tip which appears when the CT slice encompasses only the shaft of an angled needle. By obtaining images of an aspiration biopsy needle inserted vertically into a phantom and then incrementally tilting the gantry, the authors were able to compare the characteristic features of the true tip to the simulated tip. The true tip was abrupt and distinct and had an adjacent flame-like low density artifact. The simulated tip was indistinct and tapered, yet still produced the adjacent artifact. We concluded that the shape and distinctness of the end portion of the needle itself, rather than the attendant artifact, were the most reliable criteria for accurate needle tip identification. 相似文献
3.
Dominique G. Penninck DVM Antony S. Moore BVSc MVSc Amy S. Tidwell DVM Michael E. Matz DVM Greg O. Freden DVM 《Veterinary radiology & ultrasound》1994,35(4):299-306
Clinical, radiological and ultrasonographic findings from 22 cats with gastrointestinal lymphosarcoma were reviewed. The most common clinical findings were anorexia, weight loss, vomiting, lethargy, depression, fever, anemia and a palpable abdominal mass. Abdominal radiographs of 12 cats revealed a mass associated with the gastrointestinal tract and/or mesentery, and decreased serosal detail, suggestive of peritoneal effusion. The most common ultrasonographic finding was transmural gastric or intestinal thickening associated with loss of normal wall layering, reduced wall echogenicity and localized hypomotility. As is noted in people, other patterns such as transmural-segmental, transmural-nodular, transmural-bulky and mucosal infiltration were represented. In 3 cats, mesenteric lymph-adenopathy was responsible for most of the mass-effect. Fine-needle aspiration biopsy, automated microcore biopsy, endoscopic biopsy or necropsy confirmed the diagnosis of lymphosarcoma in all cats. Chemotherapy was instituted in 19 cats. Only 6 cats had a complete response to treatment. The results of this study indicate that ultrasonography is a valuable tool for the diagnosis of feline alimentary lymphosarcoma and that biopsies can be obtained under ultrasonographic guidance. 相似文献
4.
采用3×2×2因子饲养试验和2×2×2因子代谢试验,研究金霉素与赖氨酸和蛋氨酸的交互作用对肉仔鸡生产性能的影响,及金霉素对两种氨基酸代谢的影响。金霉素在饲料中添加150 mg/kg时,对0-3周肉仔鸡具有显著的促生长作用(P<0.01);并显著提高肉仔鸡的饲料采食量和饲料转化率(P<0.01),促进氮沉积(P<0.01)。对4-6周肉仔鸡的生产性能无显著影响(P>0.05);金霉素、赖氨酸和蛋氨酸存在显著的互作关系(P<0.05)。金霉素的促生长效果受饲料中赖氨酸和蛋氨酸含量的影响,当日粮中赖氨酸水平为1.3%,蛋氨酸水平为0.6%时,肉仔鸡的生长性能最高。金霉素对赖氨酸的利用率没有显著影响(P>0.05),对蛋氨酸和胱氨酸的表观利用率具有显著抑制作用(P<0.05)。研究结果表明持续低剂量金霉素与蛋氨酸和赖氨酸具有交互作用,这种互作关系影响彼此对肉仔鸡生产性能的作用效果,金霉素具有提高肉仔鸡赖氨酸需要量的作用。 相似文献
5.
SR Cho SA Ock JG Yoo B Mohana kumar SY Choe GJ Rho 《Reproduction in domestic animals》2005,40(2):171-176
The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors. 相似文献
6.
Effects of hyperbaric oxygen therapy on uncomplicated incisional and open wound healing in dogs
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7.
Laryngeal mask airway and transient hypercapnic hyperpnea for video‐endoscopic assessment of unilateral laryngeal paralysis in dogs
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8.
9.
Removal of hemangiosarcoma cells from canine blood with a cell salvage system and leukocyte reduction filter
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10.