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981.
Defibrinated bovine plasma inhibits retroviral transcription by blocking p52 activation of the NFkappaB element in the long terminal repeat. 下载免费PDF全文
982.
Tara M Harrison James Sikarskie Barbara Kitchell Diana S Rosenstein Heather Flaherty Scott D Fitzgerald Matti Kiupel 《Journal of zoo and wildlife medicine》2007,38(2):333-336
A 14 yr-old male, vasectomized African lion (Panthera leo) exhibited mild weight loss despite adequate appetite. Splenomegaly was diagnosed on physical examination. On the basis of hematology and clinical pathology, malignant lymphoma with chronic lymphocytic leukemia was diagnosed. Abdominal exploratory surgery and splenectomy were performed. Histologic examination and immunohistochemistry confirmed a small cell peripheral T-cell lymphoma. Initial treatments consisted of doxorubicin and prednisone, with later addition of lomustine. The lion remained in clinical remission at 2 mo, 6 mo, and 12 mo postchemotherapy physical examinations. The lion survived 504 days from initial diagnosis. At necropsy, the only lesions consistent with lymphoma were localized epitheliotrophic infiltrates of small neoplastic T lymphocytes within the nasopharyngeal epithelium and the underlying submucosa observed on microscopic examination. 相似文献
983.
Barbara J Biller 《Veterinary Clinics of North America: Small Animal Practice》2007,37(6):1137-49; vii
The ability of the immune system to protect against tumor development and to attack malignant cells once they arise has been recognized for more than 50 years. Since this time, our understanding of the complex relation between the immune system and the development of cancer has increased dramatically, largely because of improvements in the tools used to study tumor immunology at the molecular level. These advances are leading to the development of increasingly sophisticated and effective immunotherapeutics for human and veterinary oncology patients; indeed, some forms of immunotherapy already have a place alongside more conventional treatment modalities, such as surgery, radiation therapy, and chemotherapy. 相似文献
984.
985.
Martini Mina Altomonte Iolanda Sommer Matteo Federico Gili Claudia Biancani Barbara Licitra Rosario Salari Federica 《Veterinary research communications》2022,46(2):577-583
Veterinary Research Communications - Research data on milk composition in cetaceans are scattered and fragmentary. This paper analyses the gross and mineral composition, the fatty acids profile and... 相似文献
986.
Ronan A. Mullins Antía Escribano Carrera Davina M. Anderson Jean-Philippe Billet Herve Brissot Cameron Broome Hilde de Rooster Barbara M. Kirby Kathryn M. Pratschke Michael S. Tivers Robert N. White Donald A. Yool K. Ruth Youmans 《Veterinary surgery : VS》2022,51(1):23-33
The development of postattenuation neurologic signs (PANS) is a poorly understood and potentially devastating complication after surgical attenuation of congenital portosystemic shunts in dogs. Postattenuation neurologic signs include seizures but also more subtle neurologic signs such as depression, behavioral changes, tremors, and twitching. They most commonly occur within 7 days postoperatively and are typically unrelated to hyperammonemia, hypoglycemia, or electrolyte disturbances. This narrative review summarizes the findings of 50 publications from 1988-2020 that report occurrence of PANS. While most published reports included only dogs affected by postattenuation seizures (PAS), others included dogs with any form of PANS. Overall, PANS (including PAS) affected 1.6%-27.3% of dogs, whereas incidence of PAS ranged from 0%-18.2%. The etiology of PANS remains unknown; however, several theories have been proposed. Risk factors include preoperative hepatic encephalopathy, increasing age, and possibly certain breeds and extrahepatic shunt morphology. There is increasing evidence that prophylactic antiepileptic drugs do not prevent PANS. Treatment is centered around controlling neurologic signs with antiepileptic drugs and providing supportive intensive care. The 30-day survival rate in studies that included a minimum of four dogs affected by PANS was 0%-100% (median, 50.0%) and 0%-75.0% (median, 37.5%) for those with PAS. Mortality associated with PANS was typically related to occurrence of generalized seizure activity. Prognostic factors positively associated with short-term survival included having a history of preoperative seizures and development of focal seizures only. If affected dogs survived to discharge, survival for several years was possible, and the majority of neurologic signs manifested as part of the phenomenon of PANS appeared to resolve. 相似文献
987.
Our primary objective was to present and test a new technique for in vitro estimation of respiration of cores taken from old trees to determine respiratory trends in sapwood. Our secondary objective was to quantify effects of tree age and stem position on respiratory potential (rate of CO2 production of woody tissue under standardized laboratory conditions). We extracted cores from one to four vertical positions in boles of +200-, +50- and +15-year-old Pinus ponderosa Dougl. ex Laws. trees. Cores were divided into five segments corresponding to radial depths of inner bark; outer, middle and inner sapwood; and heartwood. Data suggested that core segment CO2 production was an indicator of its respiratory activity, and that potential artifacts caused by wounding and extraction were minimal. On a dry mass basis, respiratory potential of inner bark was 3-15 times greater than that of sapwood at all heights for all ages (P < 0.0001). Within sapwood at all heights and in all ages of trees, outer sapwood had a 30-60% higher respiratory potential than middle or inner sapwood (P < 0.005). Heartwood had only 2-10% of the respiratory potential of outer sapwood. For all ages of trees, sapwood rings produced in the same calendar year released over 50% more CO2 at treetops than at bases (P < 0.0001). When scaled to the whole-tree level on a sapwood volume basis, sapwood of younger trees had higher respiratory potential than sapwood of older trees. In contrast, the trend was reversed when using the outer-bark surface area of stems as a basis for comparing respiratory potential. The differences observed in respiratory potential calculated on a core dry mass, sapwood volume, or outer-bark surface area basis clearly demonstrate that the resulting trends within and among trees are determined by the way in which the data are expressed. Although these data are based on core segments rather than in vivo measurements, we conclude that the relative differences are probably valid even if the absolute differences are not. 相似文献
988.
20世纪90年代初,由一些国家的企业、环境与社会方面的非政府组织和致力于提高森林经营水平与木材供应渠道透明度的人士,共同发起了森林认证行动,鼓励人们以购买通过森林认证的木材产品,也就是购买贴有认证标签、证明其产品是来自经营良好森林的木材的实际行动,来保护人类赖以生存的森林,该行动得到广泛的支持。人们已达成森林认证可促进森林的可持续经营和保证产品的市场准入的共识。 目前,森林认证,尤其是森林管理委员会(FSC)体系内的森林认证,正在全球兴起,至今已有46个国家的2368.9万hm~2森林进行了森林认证。 森林认证在我国刚刚起步,了解者甚少。随着我国加入WTO的临近,为了将我国的木材产品立足于国际市场,为了我国森林的可持续发展,森林认证工作应尽快在我国开展。可喜的是,今年已由非政府组织、木材生产企业、科研单位、政府部门、森林经营单位等成立了森林认证工作组;国家林业局已专门设立了抓森林认证工作的相应机构;中国林科院科信所也承担了森林认证的科研项目。森林认证工作在中国正式启动。 森林认证与社区林业密切相关。在森林认证的原则和标准中,在参与性上,与社区林业强调当地群众参与森林管理的主导思想一致。在原则和标准中强调了明确林地的所有权和使用权;强调了尊重包括当地社区在 相似文献
989.
Tree- and needle-age-dependent variations in antioxidants and photoprotective pigments in Norway spruce needles at the alpine timberline 总被引:1,自引:0,他引:1
To cope with environmental stress, plants are equipped with antioxidative (e.g., ascorbate, glutathione and alpha-tocopherol) and photoprotective (e.g., xanthophyll cycle pigments) defense systems. We investigated the defense capacities of three tree age classes (mature, sapling and seedling) of Norway spruce (Picea abies (L.) Karst.) at a field site near the timberline. Biochemical data were expressed on both a needle dry mass and a surface area basis. Compared with current-year needles, previous-year needles contained higher mass- and area-based concentrations of chlorophylls and alpha-tocopherol, and a larger xanthophyll cycle pool that was in a more epoxidized state. Total glutathione concentration was lower, the glutathione pool was more reduced and the ascorbate pool was more oxidized in previous-year needles than in current-year needles. Needle concentrations of glutathione and alpha-tocopherol increased and chlorophyll concentration decreased with increasing tree age when expressed on a surface area basis. On a dry mass basis, these trends were reversed or nonexistent. The ascorbate pool was more reduced and the glutathione pool was more oxidized in needles of mature trees than in needles of saplings and seedlings. The proportion of protective xanthophyll cycle pigments decreased and the de-epoxidation state increased with increasing tree age. We conclude that tree age and the basis of expression of antioxidant concentration--surface area or dry mass--are important in scaling from seedlings to large trees. 相似文献
990.
We investigated effects of stem phloem girdles on apical control of branch angle, stem and branch growth and stem air content in six conifer species. A stem girdle 2 cm above a branch caused the branch to bend upward in all six species. Upward bending was associated with increased formation and action of compression wood (CW) in the lower portion of the branch. Compression wood also formed in the main stem below the branch, suggesting increased auxin production in the branch. A stem girdle 2 cm below a branch (the branch remained directly connected to the apex and distal branches) released the branch from apical control in Tsuga canadensis (L.) Carr., Pinus contorta Dougl. ex Loud. and Pseudotsuga menziesii (Mirb.) Franco. The branch bent up, but there was no CW formation in the stem. In Pinus rigida Mill., the branch exhibited increased cambial activity but did not bend up. A stem girdle > 20 cm below a branch did not release the branch from apical control in any of the species. These results support the hypothesis that branches compete with the subjacent stem for branch-produced photosynthate and that when the branch lacks this competitive sink it is released from apical control. A stem girdle 2 cm below a branch did not cause release of apical control in either Juniperus virginiana L. or Picea abies (L.) Karst. In these species, decreased shoot elongation and cambial activity above the girdle probably prevented release. A stem girdle 2 cm below a branch increased air content in the stem below the girdle in four of five species, whereas the other girdle treatments had no significant effect on stem air content. Although growth was inhibited above the girdle in the two species with the largest increase in air content, growth was not inhibited in the other species. High air content in stem segments isolated from distal auxin and carbohydrate sources is consistent with the hypothesis that a carbohydrate supply is required to refill embolized cells. 相似文献