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11.
德国及蒙古沙棘品种无性系生物学和观赏性价值评估 总被引:1,自引:0,他引:1
沙棘由于其有丰富的内含物和多方面的用途正被作为"新兴水果"而赢得了人们越来越多的重视和喜爱.通过在柏林Baumschulenweg的育种工作,到目前为止,已经育成不同成熟期的5个雌性和4个雄性沙棘品种.更多的由欧洲和蒙古原生种产生的杂交选育工作仍在进行中.将这些无性系按照其生物学和果实性状进行评估.就单个性状来讲,各品种之间的差异非常大(比如维生素的含量在17~340mg/100g之间变动,胡萝卜素的变动范围为6.5~23.8mg/100g).这表明,进一步的育种改良完全有可能.所有用于比较的沙棘品种由在德累斯顿Pillnitz进行的育种工作获得,这些品种将被进一步研究.为了保险起见,以及为了解决后来有可能产生的育种及植物病理学方面的问题,必须尽可能保存现有的所有的某一品种的基因多样性.为此目的,由国家资助扶持的基因库的建立是很有必要的. 相似文献
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Nonendoscopic Antegrade Percutaneous Gastrostomy: The Effect of Preplacement Gastric Insufflation on Tube Position and Intra-Abdominal Anatomy 总被引:1,自引:0,他引:1
Erik M. Clary Elizabeth M. Hardie William D. Fischer rew E. Kyles 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(1):15-20
Nonendoscopic tube gastrostomy was performed on 41 anesthetized dogs using the technique of Fulton and Dennis with or without gastric insufflation prior to tube placement. Immediately after tube placement, dogs were euthanized and postmortem examinations performed. When gastric insufflation was not performed (group I), gastrostomy tubes penetrated the visceral surface of the stomach in 25% of dogs. The deep leaf of the omentum was interposed between stomach and body wall in the majority of these dogs, exposing other intra-abdominal organs to potential injury. Additionally, displacement and tethering of the spleen cranial to the gastrostomy site were observed in 33% of dogs in group I. Similar results were obtained when preplacement gastric insufflation was performed after the orogastric tube was inserted sufficiently far to displace the stomach laterally against the body wall (group II). In contrast, consistent positioning of gastrostomy tubes through the parietal surface of the stomach was achieved when the stomach was insufflated prior to lateralizing the left abdominal wall with the gastric end of the orogastric tube (group III). It was concluded that the blind percutaneous gastrostomy technique is made safer by insufflating the stomach immediately prior to pushing the gastric wall laterally into contact with the parietal peritoneum. J Vet Intern Med 1996;10:15–20. Copyright © 1996 by the American College of Veterinary Internal Medicine . 相似文献
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A biotype of Aster squamatus (Sprengel) Hieronymus with suspected resistance to the ALS-inhibiting herbicide imazapyr was detected in a chicken farm in the province of Seville, Spain, which had been treated once a year with imazapyr for 10 years. Resistance to imazapyr in this biotype was studied using dose-response experiments, absorption and translocation assays, metabolism studies and ALS activity assays. The rate of imazapyr required to inhibit A squamatus growth by 50% (ED50) was 15 times higher for the R (resistant) than for the S (susceptible) biotype. Cross-resistance existed for the ALS-inhibitors imazamox, imazethapyr, amidosulfuron, nicosulfuron, rimsulfuron, triasulfuron and tribenuron, but not for bensulfuron. Control of A squamatus using alternative herbicides was poor with clopyralid, intermediate with quinclorac, amitrole and MCPA, and excellent with 2,4-D, glufosinate and glyphosate. Absorption of [14C]imazapyr increased over time for both the R and S biotypes, and translocation from the treated leaf to shoots and roots was similar in both biotypes, with most of the radioactivity remaining in the treated leaf. No metabolites of imazapyr were detected in either biotype. Sensitivity of the ALS enzyme (target site) to imazapyr was lower for the R biotype (I50(R) = 4.28 x I50(S)). The mechanism of imazapyr resistance in this R biotype appears to be an altered ALS conferring decreased sensitivity to imazapyr at the whole-plant level. 相似文献
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Phillips DE Radlinsky MG Fischer JR Biller DS 《Journal of the American Animal Hospital Association》2003,39(4):349-354
Reports of cystic thyroid and parathyroid masses in cats are uncommon. Herein, the authors describe a series of four cats with cystic ventral cervical lesions, among them thyroid cyst (n=1), thyroid cystadenoma (n=2), and parathyroid adenocarcinoma (n=1). Presentations ranged from completely asymptomatic cervical swellings to signs related to local compression of adjacent structures (e.g., trachea). Ultrasonographic evaluation was helpful in localization of the mass in two cases. Hormone analysis and concentration of cystic fluid were performed in one cat. Surgical excision was performed successfully in three cases. Histopathological examination was performed in all four cases. Long-term prognosis was excellent for those cases in which follow-up was available. 相似文献
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Harkin KR Cowan LA Andrews GA Basaraba RJ Fischer JR DeBowes LJ Roush JK Guglielmino ML Kirk CA 《Journal of the American Veterinary Medical Association》2000,217(5):681-684
OBJECTIVE: To determine hepatotoxicity of stanozolol in cats and to identify clinicopathologic and histopathologic abnormalities in cats with stanozolol-induced hepatotoxicosis. DESIGN: Clinical trial and case series. ANIMALS: 12 healthy cats, 6 cats with chronic renal failure, and 3 cats with gingivitis and stomatitis. PROCEDURES: Healthy cats and cats with renal failure were treated with stanozolol (25 mg, i.m., on the first day, then 2 mg, p.o., q 12 h) for 4 weeks. Cats with gingivitis were treated with stanozolol at a dosage of 1 mg, p.o., every 24 hours. RESULTS: Most healthy cats and cats with renal failure developed marked inappetence, groomed less, and were less active within 7 to 10 days after initiation of stanozolol administration. Serum alanine transaminase (ALT) activity was significantly increased in 14 of 18 cats after stanozolol administration, but serum alkaline phosphatase activity was mildly increased in only 3. Four cats with serum ALT activity > 1,000 U/L after only 2 weeks of stanozolol administration had coagulopathies; administration of vitamin K resolved the coagulopathy in 3 of the 4 within 48 hours. All 18 cats survived, and hepatic enzyme activities were normal in all cats tested more than 4 weeks after stanozolol administration was discontinued. Two of the 3 cats with gingivitis developed evidence of severe hepatic failure 2 to 3 months after initiation of stanozolol treatment; both cats developed coagulopathies. Histologic evaluation of hepatic biopsy specimens from 5 cats revealed diffuse hepatic lipidosis and cholestasis without evidence of hepatocellular necrosis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that stanozolol is hepatotoxic in cats. 相似文献
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The binding ability of staphylococcal protein A (SpA) and streptococcal protein G (SpG) to egg yolk antibodies of four fowl species (turkey, duck, moskovy duck and goose) was studied and compared with the binding ability to three serum antibodies from chicken, horse and cattle. SpA and SpG were not able to bind to any of the avian immunoglobulins. 相似文献
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