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491.
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493.
柑橘天然生物活性物质吖啶酮的研究与利用   总被引:1,自引:0,他引:1  
吖啶酮生物碱是一类重要的生物活性物质,芸香科柑橘类植物是天然吖啶酮的主要来源。至今已从柑橘类植物中分离得到20多种吖啶酮生物碱,它们在抗癌、抗肿瘤、抗病毒、抗疟疾和抗白血病等方面有重要作用。我国柑橘资源丰富,利用我国乃至世界丰富的柑橘资源对柑橘吖啶酮的开发利用前景广阔。对柑橘吖啶酮的已有研究多以根茎为实验材料,关于果实中吖啶酮的研究尚无报道。阐述了柑橘吖啶酮的结构特点、生理活性、生物合成和研究进展情况,并提出了植物天然吖啶酮的研究现状和形势,同时指明了在柑橘吖啶酮研究领域存在的问题及今后在此领域的研究重点和方向。  相似文献   
494.
495.
This case describes an outbreak of low pathogenic hemagglutinin 9 neuraminidase 2 avian influenza virus (AIV) in two white-bellied bustards (Eupodotis senegalensis), one stone curlew (Burhinus oedicnemius), and a blacksmith plover (Antibyx armatus) in a private zoologic collection in Dubai, United Arab Emirates. The four birds showed signs of respiratory disease, and all died as a result of disease or euthanasia. Attention has been paid to the diagnostic process and common differential diagnosis for upper respiratory tract disease in bustards, curlews, and plovers. To the knowledge of the authors, AIV has not been previously described in these species.  相似文献   
496.
GPV VP1-VP3非重叠序列重组原核表达多肽的应用研究   总被引:1,自引:0,他引:1  
鹅细小病毒感染(Goose parvovirus infection,GPVI)俗称小鹅瘟(Gosling plague,GP)或Derzys's病,在世界养鹅国家持续不断,始终未能得到有效控制。其原因相当复杂,除了长期以来缺乏科学的免疫程序和安全的基因工程疫苗外,在一定程度上与缺乏有效的检测方法有关。GPV全毒苗在预防  相似文献   
497.
This report describes the morphologic, ultrastructural, and immunophenotypic features of a nodular ganglioneuroblastoma in the jejunum of a 13-month-old Holstein-Friesian heifer. On histologic examination, the mass was composed of clusters of neuroblasts and isolated ganglionic neurons in abundant neurophilic matrix that was surrounded by scanty Schwannian stroma. On ultrastructure examination, the large ganglionic neuron-like cells had unmyelinated neurites. Most ganglionic neuron-like tumor cells expressed neurofilament, neuron-specific enolase, chromogranin A, and S-100, whereas the Schwann-cell-like stromal cells expressed S-100 and vimentin. Both brain-derived neurotrophic factor (BDNF) and tropomyosin-related kinase-B (Trk-B) were expressed in ganglionic neuron-like tumor cells, which suggested the activation or reactivation of an embryonic autocrine BDNF/Trk-B pathway that could have prolonged cell survival and promoted differentiation with neurite formation.  相似文献   
498.
Hepatitis E is a human disease mainly characterized by acute liver illness, which is caused by infection with the hepatitis E virus (HEV). Large hepatitis E outbreaks have been described in developing countries; however, the disease is also increasingly recognized in industrialized countries. Mortality rates up to 25% have been described for pregnant women during outbreaks in developing countries. In addition, chronic disease courses could be observed in immunocompromised transplant patients. Whereas the HEV genotypes 1 and 2 are mainly confined to humans, genotypes 3 and 4 are also found in animals and can be zoonotically transmitted to humans. Domestic pig and wild boar represent the most important reservoirs for these genotypes. A distinct subtype of genotype 3 has been repeatedly detected in rabbits and a few human patients. Recently, HEV genotype 7 has been identified in dromedary camels and in an immunocompromised transplant patient. The reservoir animals get infected with HEV without showing any clinical symptoms. Besides these well‐known animal reservoirs, HEV‐specific antibodies and/or the genome of HEV or HEV‐related viruses have also been detected in many other animal species, including primates, other mammals and birds. In particular, genotypes 3 and 4 infections are documented in many domestic, wildlife and zoo animal species. In most cases, the presence of HEV in these animals can be explained by spillover infections, but a risk of virus transmission through contact with humans cannot be excluded. This review gives a general overview on the transmission pathways of HEV to humans. It particularly focuses on reported serological and molecular evidence of infections in wild, domestic and zoo animals with HEV or HEV‐related viruses. The role of these animals for transmission of HEV to humans and other animals is discussed.  相似文献   
499.
Objective— To describe outcome after an alternative unilateral approach to the thoracolumbar spine for dorsal laminectomy.
Study Design— Retrospective clinical study.
Animals— Dogs (n=14) with thoracolumbar spinal cord compression.
Methods— Thoracolumbar spinal cord compression was lateral (6 dogs), dorsal (4), and dorsolateral (4) caused by subarachnoid (7) and synovial cysts (2) and intradural-extramedullary neoplasia (5). All dogs were treated by dorsal laminectomy with osteotomy of the spinous process using a unilateral paramedian approach. The contralateral paraspinal muscles were not stripped from the spinous process and the osteoligamentous complexes were preserved. Retraction of the spinous process and muscles to the contralateral side resulted in complete visualization of the dorsal vertebral arch thereby allowing dorsal laminectomy to be performed.
Results— No technique complications occurred. Approximately 75% exposure of the spinal cord (dorsal and lateral compartments) was achieved providing adequate visualization and treatment of the lesions. Transient deterioration of neurologic state occurred in 5 dogs because of extensive spinal cord manipulation. At long-term follow-up, 6 dogs were normal, 6 had clinical improvement, and 2 were unchanged.
Conclusion— Dorsal laminectomy after osteotomy and retraction of the spinous process may be considered in canine patients with dorsal, dorsolateral, or lateral compression to facilitate adequate decompression of the spinal cord.
Clinical Significance— This surgical technique offers an alternative approach to the thoracolumbar spine and spinal cord by a modified dorsal laminectomy that preserves the paraspinal muscle integrity on the contralateral side.  相似文献   
500.
Landscape services: the concept and its practical relevance   总被引:1,自引:1,他引:0  
Recently, in addition to the popular concept of “ecosystem services” (ES), the term “landscape services” (LS) has come into use. We are examining the question of whether a stronger focus on LS would be useful, particularly with regard to case studies carried out in Germany. Important reasons for introducing the term LS include the prominent role of spatial aspects, the reference to landscape elements and the landscape character, and the relevance of LS for landscape planning. We found no strong arguments for replacing the concept of ES by LS; however, we do prefer a situation-related use of both concepts. We propose the following definition: Landscape services are the contributions of landscapes and landscape elements to human well-being.  相似文献   
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