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11.
兰旗榆为白榆的一个地理生态变种,在锡盟浑善达克沙地及其南缘的镶黄旗、正镶白旗、正兰旗等地区生长表现突出。该树种较之其它的白榆品种具有抗旱、抗寒、抗风沙,物候期早,所需积温低以及生长迅速等优良特性,对我区北部干旱草原气候生态条件适应能力强,在草原造林中有着其它树种不可替代的地位和作用,建议大力推广。 相似文献
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Gross and microscopical lesions in mice intravenously infected with the Welgevonden strain of Cowdria ruminantium closely resembled the lesions described in cattle, sheep and goats. A high concentration of organisms was present in alveolar endothelial cells. Cytopathic changes in parasitized and non-parasitized endothelial cells and the morphology of the organisms are described and compared with the Ball3 strain of C. ruminantium. Possible mechanisms in the development of the lung oedema are considered and the role of mice as animal model is discussed. 相似文献
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中国正在不断推进农村绿色经济转型与乡村振兴战略,田园综合体等各种以生态环境为导向的农业开发模式是乡村振兴建设的新途径,驱动农业固碳减排的同时,也带动着传统农业不断向现代农业发展的转变。以EOD(Ecology-Oriented-Development,生态环境导向的开发)模式的上海市金山区枫泾镇郊野村庄田园综合体为研究对象,在现场调研与数据统计的基础上,分析了园区内的碳输入和碳输出以及碳在园内各区域间的流动和储积;同时,根据碳源和碳汇清单和估算结果,分析了田园综合体各区的碳平衡特点。结果显示,上海市金山区郊野村庄田园综合体2021年碳平衡表现为净碳汇区,净碳汇量为152.09 tC,其中排放量为588.79 tC,碳固定量为740.88 tC。田园综合体内,作物种植区通过低碳有机种植模式成为净碳汇量最大的区域,净碳汇量185.76 tC;水产养殖区通过高效的水草多级循环利用模式净碳汇量达62.20 tC;高空间利用率的立体农业区因农肥的碳排放量大表现为碳源区,净碳汇量为-10.81 tC;生产生活区是最大的碳源区,净碳汇量达-85.05 tC,人类文旅活动是其中最大的碳排放源。分析结合该田园综合体的碳流动,提出了发展高物质循环利用率、高空间利用率、低碳有机种植模式和农业科学管理四个农业降碳增汇的方向。 相似文献
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Thoracic Limb Morphology of the Ring‐tailed Lemur (Lemur catta) Evidenced by Gross Osteology and Radiography
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M. Makungu H. B. Groenewald W. M. du Plessis M. Barrows K. N. Koeppel 《Anatomia, histologia, embryologia》2015,44(4):288-298
There is limited information available on the morphology of the thoracic limb of the ring‐tailed lemur (Lemur catta). This study describes the morphology of the thoracic limb of captive ring‐tailed lemurs evidenced by gross osteology and radiography as a guide for clinical use. Radiographic findings of 12 captive ring‐tailed lemurs are correlated with bone specimens of three adult animals. The clavicle is well developed. The scapula has a large area for the origin of the m. teres major. The coracoid and hamate processes are well developed. The lateral supracondylar crest and medial epicondyle are prominent. The metacarpal bones are widely spread, and the radial tuberosity is prominent. These features indicate the presence of strong flexor muscles and flexibility of thoracic limb joints, which are important in arboreal quadrupedal locomotion. Furthermore, an ovoid ossicle is always seen at the inter‐phalangeal joint of the first digit. Areas of increased soft tissue opacity are superimposed over the proximal half of the humerus and distal half of the antebrachium in male animals as a result of the scent gland. Knowledge of the morphology of the thoracic limb of individual species is important for accurate interpretation and diagnosis of musculoskeletal diseases. 相似文献
16.
du Toit WJ Lisjak K Stander M Prevoo D 《Journal of agricultural and food chemistry》2007,55(8):2765-2769
The effect of oxygen on the levels of glutathione, an important antioxidant, in must and wine was studied using a novel LC-MSMS method for the analysis of reduced and oxidized glutathione. This study found that the storage of grape juice at high SO2 and ascorbic acid levels at -20 degrees C did not lead to a decrease in reduced glutathione levels. The effect of varying the oxygen levels in South African white grape juices, which included a reductive treatment (less than 0.3 mg/L dissolved O2 added), a control treatment (between 1.0 and 1.5 mg/L dissolved O2 added), and an oxidative treatment (3.5-4 mg/ L dissolved O2 added, without SO2) on reduced glutathione levels in the juice and resulting wine was also investigated. A custom build press was used to press whole bunches of two different Sauvignon Blanc and Colombard grapes. Alcoholic fermentation and oxygen additions to the must led to lower reduced glutathione levels in the wine. Reduced glutathione levels were only significantly higher in the wine made from reductive juice that had the highest initial reduced glutathione levels in the grapes. 相似文献
17.
M. Makungu H. B. Groenewald W. M. du Plessis M. Barrows K. N. Koeppel 《Anatomia, histologia, embryologia》2014,43(3):190-202
In family Lemuridae, anatomical variations exist. Considering its conservation status (near threatened) and presence of similarities between strepsirrhines and primitive animals, it was thought to be beneficial to describe the gross osteology and radiographic anatomy of the pelvis and hind limb of ring‐tailed lemurs (Lemur catta) as a reference for clinical use and species identification. Radiography was performed in 14 captive adult ring‐tailed lemurs. The radiographic findings were correlated with bone specimens from two adult animals. Additionally, computed tomography of the hind limbs was performed in one animal. The pelvic bone has a well‐developed caudal ventral iliac spine. The patella has a prominent tuberosity on the cranial surface. The first metatarsal bone and digit 1 are markedly stouter than the other metatarsal bones and digits with medial divergence from the rest of the metatarsal bones and digits. Ossicles were seen in the lateral meniscus, inter‐phalangeal joint of digit 1 and in the infrapatellar fat pad. Areas of mineral opacity were seen within the external genitalia, which are believed to be the os penis and os clitoris. Variations exist in the normal osteology and radiographic appearance of the pelvis and hind limb of different animal species. The use of only atlases from domestic cats and dogs for interpretative purposes may be misleading. 相似文献
18.
du Noüy L 《Science (New York, N.Y.)》1935,82(2124):254-256
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J L Du Plessis L Malan Z E Kowalski 《The Onderstepoort journal of veterinary research》1987,54(3):313-318
Hypotheses on the pathogenesis of heartwater, which have been published so far, are briefly reviewed. Attempts were made at counteracting the effects of vaso-active substances released by mast cells by treating mice infected with Cowdria ruminantium with antagonists to histamin and serotonin on one hand, and with mast cell stabilizers on the other, but were not successful. Preliminary findings suggest that a hypersensitive type of reaction, triggered by the release of pharmacologically active substances, may possibly be basic to the pathogenesis of heartwater. Complement, and the products of arachidonic acid metabolism, possibly play a role in the release of the vaso-active substances. 相似文献