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Between 1989 and 1995 nine Great Danes were presented to the small animal clinic of the University of Zurich Teaching Hospital with glaucoma and multiple cysts in the anterior and posterior chamber. In four of the nine dogs cysts were present in both eyes; however, bilateral glaucoma was seen in one case only. Mean intraocular pressure (IOP) at initial presentation was 42 mmHg measured by applanation tonometry. With the exception of one dog, all animals were treated medically for a minimum of 13 days. Two animals were subsequently lost to follow up. Two dogs underwent evisceration with implantation of a silicone prosthesis. The glaucomatous globe was enucleated in three dogs. One owner declined surgery and the dog remained buphthalmic with a poorly controlled IOP. One animal remained visual after trans-scleral diode laser cyclophotocoagulation. Histopathology of the three enucleated globes showed multiple cysts originating from the ciliary body epithelium. The mechanism of IOP elevation is probably by anterior displacement of the iris with narrowing of the angle and collapse of the ciliary cleft. A delicate pre-iridal fibrovascular membrane was also seen in each case, which could have also contributed to the elevation of IOP. The high odds ratio of 2.23 (CI 95% 1.14, 3.99) for glaucoma and 37.01 (CI 95% 16.42, 77.81) for ciliary body cysts suggests they are both inherited in this breed. Pedigree analysis of the affected dogs failed to definitely reveal the mode of inheritance.  相似文献   
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Climate change. A guide to CO2 sequestration   总被引:1,自引:0,他引:1  
Lackner KS 《Science (New York, N.Y.)》2003,300(5626):1677-1678
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Stabilizing the carbon dioxide-induced component of climate change is an energy problem. Establishment of a course toward such stabilization will require the development within the coming decades of primary energy sources that do not emit carbon dioxide to the atmosphere, in addition to efforts to reduce end-use energy demand. Mid-century primary power requirements that are free of carbon dioxide emissions could be several times what we now derive from fossil fuels (approximately 10(13) watts), even with improvements in energy efficiency. Here we survey possible future energy sources, evaluated for their capability to supply massive amounts of carbon emission-free energy and for their potential for large-scale commercialization. Possible candidates for primary energy sources include terrestrial solar and wind energy, solar power satellites, biomass, nuclear fission, nuclear fusion, fission-fusion hybrids, and fossil fuels from which carbon has been sequestered. Non-primary power technologies that could contribute to climate stabilization include efficiency improvements, hydrogen production, storage and transport, superconducting global electric grids, and geoengineering. All of these approaches currently have severe deficiencies that limit their ability to stabilize global climate. We conclude that a broad range of intensive research and development is urgently needed to produce technological options that can allow both climate stabilization and economic development.  相似文献   
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The discovery of distinct modes of asymmetric catalysis has the potential to rapidly advance chemists' ability to build enantioenriched molecules. As an example, the use of chiral cation salts as phase-transfer catalysts for anionic reagents has enabled a vast set of enantioselective transformations. Here, we present evidence that a largely overlooked analogous mechanism wherein a chiral anionic catalyst brings a cationic species into solution is itself a powerful method. The concept is applied to the enantioselective fluorocyclization of olefins with a cationic fluorinating agent and a chiral phosphate catalyst. The reactions proceed in high yield and stereoselectivity, especially considering the scarcity of alternative approaches. This technology can in principle be applied to the large portion of reaction space that uses positively charged reagents and reaction intermediates.  相似文献   
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Abstract. The number of circulating haemocytes in crayfish, Pacifastacus leniusculus Dana, was reduced after injection of yeast cell walls (Zymosan) into the animals. Crayfish harbouring the parasitic fungus A. astaci as a 'latent' infection in melanized areas in the cuticle died due to unrestricted growth of unmelanized hyphae when they were injected with Zymosan. The β–1,3–gIucan laminaran, introduced into the haemocoel of P. leniusculus harbouring A. astaci hyphae in the cuticle, also caused a decrease in the total haemocyte counts (THC), but these animals survived the treatment and no unmelanized hyphae of A, astaci were found. The recovery of THC was found to be more rapid after laminaran injection than after Zymosan injection, which could explain why laminaran treated crayfish retained their resistance and could combat the A. astaci hyphae in the cuticle. The importance of the number of haemocytes in defence and well-being of crayfish is discussed.  相似文献   
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The adnexa frequently requires the general practitioner to intervene surgically to manage underlying disease or as an ancillary aid in the management of corneal disease. Both acquired and hereditary disorders are encountered. This article reviews general anatomy and physiology of the eyelids and discusses indications for the more commonly performed surgical procedures and their execution. Procedures include tarsorrhaphy, management of eyelid lacerations, eyelid tumor resection, correction of upper and/or lower lid entropion, ectropion, a medial and lateral canthoplasty, colobomatous syndrome in the cat, management of distichiasis, trichiasis and ectopic ciliae, and reduction of a prolapse of the gland of the third eyelid. Finally a surgical pack inventory useful for adnexal surgery is described.  相似文献   
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规模化猪场猪支原体肺炎控制及净化技术研究   总被引:10,自引:0,他引:10  
在四川蒲江某规模化8养猪场 ,对该场的猪支原体肺炎采用以监测、免疫为主,隔离、治 疗、淘汰、消毒等综合防制技术进行控制与净化,对全场有猪支原体肺炎症状的猪及可疑病猪进行隔治疗,治愈后的猪经与易感猪同居感染不发病,分离猪肺炎支原体为阴性,试验表明治愈后的猪不带菌。对全场种猪和后备健康猪群进行猪支原体肺炎疫苗的免疫接种,经抗体监测和攻毒试验,免疫后240天猪支原体肺炎的IHA抗体仍可达到1:10,保护率  相似文献   
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