人工增温条件下不同氮素形态比对重齿风毛菊气体交换及其群落生物量的影响     

吴楚  芦光新  德科加  张明  王军邦 《草地学报》2015,23(6):1129-1135

在青藏高原三江源区草地上,以开顶式温棚模拟增温,在其内部施用不同形态氮素(硝态氮和氨态氮)比例的氮肥,对重齿风毛菊(Saussurea katochaete)的光合速率、叶绿素荧光及其群落总生物量进行研究,旨在为人工管理草场施肥提供指导。结果表明:重齿风毛菊的光合速率随硝态氮比例增加而下降,气孔导度则增加。其他气体交换参数没有规律性变化。光系统II(PSII)光化学量子产量(Φ_PSII)在硝态氮比例为0%时最大,非光化学瘁灭(NPQ)则随硝态氮比例增大而增大。重齿风毛菊所在群落的总生物量在硝态氮和氨态氮比例平衡时达到最大。结果表明不同比例氮素施肥会对青藏高原草甸植物的净光合速率和群落总生物量产生影响。  相似文献   

头孢维星研究进展     

宋福杰  刘明春  符特 《中国畜牧兽医》2014,41(3):237-241

头孢维星是新型的第3代头孢菌素类动物专用抗生素,因其吸收快、达峰时间短、生物利用度高、消除半衰期长、药效持久,单次皮下注射即可达到14 d的有效血药浓度,在兽医临床具有广阔前景。作者对头孢维星研发现况、作用机制、体内外抗菌活性及临床应用作一综述,以期为其在兽药临床应用提供参考。  相似文献   

Localization of Oestrogen Receptors in the Epididymis During Sexual Maturation of the Domestic Cat     

J Schön  S Neumann  DE Wildt  BS Pukazhenthi  K Jewgenow 《Reproduction in domestic animals》2009,44(S2):294-301

Oestrogens are involved in regulation of spermatogenesis and sperm maturation and are essential for male fertility. To study the role of oestrogens on epididymal function in the domestic cat, we analyzed the localization patterns of oestrogen receptors (ERs) within the epididymis of juvenile, pubertal and adults using immunohistochemistry. Cat epididymal tissues obtained during routine castrations were fixed in chilled Bouin's solution and processed for immunohistochemistry with ER-specific antibodies. For a certain receptor type, ER localization was influenced by donor age. In the juvenile epididymis, ERα was localized in the nuclei of epithelial cells of efferent ducts and undifferentiated epithelium of the ductus epididymis. During puberty, ERα localization in the undifferentiated epithelium of the epididymis shifted from the nuclei to the cytoplasm and plasma membrane. Oestrogen receptor-α level was highest in the pubertal and adult epididymis, especially within the cytoplasm and in plasma membranes of caput epithelial cells. This finding was suggestive of a role in fluid reabsorption within the efferent ducts and the epididymis. In corpus and cauda regions, ERα was less abundant, suggesting a minor role for oestrogens in sperm storage areas. Interestingly, localization of ERβ was neither influenced by age nor location within the epididymis and was ubiquitous throughout. Results demonstrate that oestrogen actions within the epididymis may be predominantly mediated through ERα during sexual maturation in the domestic cat.  相似文献   

Follicular Morphology, Oocyte Diameter and Localisation of Fibroblast Growth Factors in the Domestic Dog Ovary     

N Songsasen  A Fickes  BS Pukazhenthi  DE Wildt 《Reproduction in domestic animals》2009,44(S2):65-70

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Effect of magnitude and direction of force on laryngeal abduction: Implications for the nerve‐muscle pedicle graft technique     

P. CRAMP  F. J. DERKSEN  J. A. STICK  H. DE FEIJTER‐RUPP  N. G. ELVIN  J. HAUPTMAN  N. E. ROBINSON 《Equine veterinary journal》2009,41(4):328-333

Reasons for performing study: The nerve‐muscle pedicle graft technique is a treatment for recurrent laryngeal neuropathy (RLN), but the optimal placement of the pedicles within the cricoarytenoideus dorsalis (CAD) muscle is unknown. Hypothesis: The magnitude and direction of force placed on the muscular process of the left arytenoid cartilage affects the magnitude of laryngeal abduction. Methods: Five larynges were harvested from cadavers. Using increments of 0.98 N, a dead‐weight force generator applied a force of 0–14.7 N for 1 min each to the left muscular process at 0, 10, 20, 30, 40, 50, 60 and 70° angles. The rima glottis was photographed digitally 1 min after each force had been applied. Distances between biomarkers (Lines 1–4) and right to left angle quotient (RLQ) were used to assess the degree of left arytenoid abduction. Results: Increasing force from 0–14.7 N progressively and significantly increased the length of all lines and RLQ, indicating abduction. Furthermore, there was a significant interaction between force and angles. Applying forces of 7.84 N or greater (Lines 2–4 and RLQ) or 11.76 N or greater (Line 1) at angles 0, 10, 20 and 30° resulted in significantly greater abduction than applying the same forces at 40, 50, 60 and 70°. Angles of 0–30° correspond with the direction of pull exerted by the lateral compartment of the CAD muscle. Conclusion: In RLN, nerve‐muscle pedicle grafts should be placed preferentially in the lateral rather than in the medial compartment of the CAD muscle. Potential relevance: The information presented can be used to assist surgeons in the planning and application of the nerve‐muscle pedicle graft procedure.  相似文献   

达赉湖保护区水鸟生境利用研究   总被引：2，自引：0，他引：2  

特喜铁  梁秀梅 《野生动物》2009,30(5):252-254

2007年3～11月,通过样带法对内蒙古达赉湖自然保护区内水乌生境利用进行了研究。研究表明,达赉湖保护区不同种水乌的生境利用显著不同,鹳形目、鸥形目和鹈形目鸟类主要选择在河漫滩草甸,鸻形目鸟类主要选择泥岸沼泽,鹤形目和鸊（？）目鸟类主要选择浅水植被区,雁形目鸟类主要选择深水区。  相似文献   

Treatment of a Periarticular Tibial Fracture in a Foal with a Hybrid External Fixator   总被引：1，自引：0，他引：1  

ROBERTA FERRO DE GODOY  DScVM    RICHARD R. FILGUEIRAS  MS    LÍLIAN A. GONTIJO  DVM    FÁBIO HENRIQUE BEZERRA XIMENES  DVM    LIANA VILLELA DE GOUVÊA  DVM    CRISTIANE DA SILVA PEREIRA  DVM    RICARDO M. ALMEIDA  MS    CECI RIBEIRO LEITE  DVM    ANTÔNIO RAPHAEL T. NETO  DScVM    JOSÉ RENATO JUNQUEIRA BORGES  DScVM 《Veterinary surgery : VS》2009,38(5):650-653

Objective— To report repair of a right proximal tibial Salter-Harris type II fracture in a foal with a hybrid external fixator (HEF).
Study Design— Case report.
Animals— A 5-month-old male foal.
Methods— After open surgical reduction, an HEF built with wires, 2 half-rings, 3 half-threaded connecting rods, and Schanz pins was used to stabilize the fracture.
Results— Immediately after surgery, the foal had relatively good weight bearing. The HEF was removed at 60 days after radiographic confirmation of healing.
Conclusions— HEF can be used to stabilize a proximal tibial Salter-Harris type II fracture in a 5-month-old foal.
Clinical Relevance— HEF should be considered as another option for repair of proximal tibial Salter-Harris type II fractures in foals.  相似文献   

复方恩诺沙星可溶性粉对畜禽主要致病菌的体外抑菌效果   总被引：3，自引：1，他引：2  

德育慧  樊明春  王枫 《动物医学进展》2009,30(7):46-49

采用纸片扩散法(K-B法)测定复方恩诺沙星可溶性粉对畜禽主要致病菌的敏感性,采用试管倍比稀释法测定复方恩诺沙星可溶性粉对畜禽主要致病菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。结果表明,病原性大肠埃希菌、绿脓杆菌、金黄色葡萄球菌、鸡巴氏杆菌、猪巴氏杆菌和链球菌对复方恩诺沙星可溶性粉敏感,复方恩诺沙星可溶性粉对畜禽主要致病菌的MIC为0.0279μg/mL~3.575μg/mL,MBC为0.055μg/mL~7.11μg/mL。  相似文献   

IMAGING DIAGNOSIS—ACUTE NECROTIZING MYOPATHY IN A DOG     

LUISA DE RISIO  JAMES FRASER MCCONNELL  ALBERTA DE STEFANI  LARA MATIASEK  ALEJANDRO LUJAN FELIU-PASCUAL  GLORIA DIANE SHELTON 《Veterinary radiology & ultrasound》2009,50(6):639-643

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施肥对青海省山地草原类草场地上生物量的影响     

德科加  周青平  徐成体  蒋卫平 《中国土壤与肥料》2010,(3)

在青海省山地草原类草场进行了施肥试验,以确定不同施肥时期、不同施肥量组合对天然草地牧草鲜重的影响。结果表明,施肥可大幅度提高牧草产量,且因施肥量及施肥时期的不同,牧草产量差异大。施肥时间和施肥量间存在着交互作用,两者共同作用于牧草产量。施肥时间选择在6月25日,较其后的3个时期牧草鲜重分别增产20.71%、25.44%、27.28%;随着施肥时间的推后,牧草鲜重呈现持续下降趋势;3个不同施肥量处理的牧草鲜重分别比不施肥增产80.97%、86.26%和79.78%,施肥量在0~600 kg/hm2区间内,牧草鲜重变化呈抛物线型。通过综合比较分析,青藏高原山地草原类草场施氮肥时应选择在6月中下旬,施肥量应控制在420~600 kg/hm2之间。  相似文献