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排序方式: 共有133条查询结果,搜索用时 15 毫秒
1.
İsmail Hakkı Nur William Pérez Horst Erich König 《Anatomia, histologia, embryologia》2021,50(3):658-667
This study aims to reveal the morphological properties of facial nerve and the middle ear in Van cats. Study material was composed of 6 female Van cats. Dissections were performed under a Zoom Stereo Microscope. There was no plexus buccalis in Van cats. The chorda tympani was observed to pass through an opening in the tympanic cavity, emerge through a small opening just behind the retroarticular process, and join the lingual nerve. A rounded anatomical formation with a size of 2.75 ± 0.3 mm was found to be located within the mastoid process of the temporal bone between the facial nerve and the auricular branch of the vagus nerve. The stapes nerve was not present. The geniculate ganglion was very prominent and about 1.00 mm high. The deep petrosal nerve was observed to emerge from the plexus tympanicus. The bulla tympanica was 18.96 ± 0.10 mm long, 13.03 ± 0.20 mm wide and 13.16 ± 0.20 mm high. After leaving the mandibular nerve, the n.tensoris tympani coursed caudally around the a.maxillaris, formed an ansa, entered the tympanic cavity through the canalis musculotubarius and reached an end in the m. tensor tympani. Due to the scarcity of studies on the middle ears of Van cats, it is thought that this study will fill a gap in the field of veterinary anatomy. 相似文献
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The history of scientific forest management in Bangladesh datesback to the nineteenth century with defined forest policiesand laws. Due to various socio-economic and socio-politicalfactors, forest cover of the country reduced drastically andall such policy initiatives proved ineffective. Although traditionalforest management objectives covered a wide range from economicbenefit to ecological stability, these have never been attainedfully. Huge population and limited land area compelled policymakers to think about alternatives to traditional forest management.One alternative, social forestry, was introduced in Bangladeshin early 1980s and has proved to be extremely successful. Whiletraditional forest management resulted in a net loss of forestresource cover, social forestry on the other hand, is playinga vital role in the expansion of forest cover (40 387 ha ofnew forest cover and 48 420 km new strip plantation since themid-1980s) benefiting thousands of poor people. Results showthat during the last four years (20002003) more than23 000 individuals benefited from the final felling of differentsocial forestry plantations (woodlot, agroforestry and stripplantation). This generated a total income of US$ 5.6 millionfor the government and US$ 5.3 million for participants plusUS$ 1.2 million for the Tree Farming Fund a 10 per centdepository reserve to sustain the practice in the long run.Although average individual final returns (US$ 223 person1)are not so attractive, some people got about US$ 5000 to US$8500 from final felling, sufficient to improve their standardof living and social position. Despite the success so far achieved,social forestry in Bangladesh still suffers from various institutionaldeficiencies like organization, skilled manpower, legitimateusufruct rights, peoples' participation from policy to implementationand clear budgetary arrangements. Besides, until now the roleof relevant actors is not well defined in all the steps of socialforestry practice in Bangladesh. Unless the participants aregiven clear legitimate usufruct rights, they will remain scepticaltowards this programme. They should have good and meaningfulaccess from planning to implementation. In the context of institutionaldevelopment, there are governmental policy guidelines and a20-year Master Plan for Bangladesh. Although some steps havebeen partially completed, there is still much to do to complywith forest policy guidelines and the Master Plan. It is shownthat in the last seven years (1995/962001/2002) onlyUS$ 15.41 million a1 has actually been spent againstan allocated sum of US$ 68.37 million a1. Therefore,if the intention is to institutionalize social forestry in Bangladesh,government and policy makers should actively come forward. Otherwisethe full potential of social forestry in Bangladesh will notbecome a reality. 相似文献
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为探究单翼迷宫式滴灌带坡度、进水压力和铺设长度对灌水均匀度的影响,以3种单翼迷宫式滴灌带为研究对象,以灌水均匀度作为评价指标,采用UL9(34)均匀正交设计试验,比较了3种不同流量的单翼迷宫滴灌带在进水压力、铺设长度和坡度作用下的灌水均匀度的变化规律。经直观分析、方差分析和多重比较进行综合评价,再由SPSS和PPR对试验数据进行数学建模。结果显示,3种单翼迷宫式滴灌带灌水均匀度的外界因素排序均为压力>坡度>长度,相比于SPSS、PPR所建立的模型具有更高的精度。研究成果不仅为灌水均匀度计算与预测提供了理论依据,还对各学科试验优化设计、高维数据建模分析提供了有效的解决方案。 相似文献
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Wafo P Kamdem RS Ali Z Anjum S Begum A Oluyemisi OO Khan SN Ngadjui BT Etoa XF Choudhary MI 《Fitoterapia》2011,82(4):642-646
A new diterpenoid, 15-angeloyloxy-16,17-epoxy-19-kauronic acid (1), along with five known metabolites, 16-kauren-19-oic acid (2), 6′-hydroxy-2′,3′,4,4′-tetramethoxychalcone (3), isosakuranetin (4), acacetin (5), and kaempferide (6) was isolated from the organic extracts of the roots of Chromoleana odorata. Their structures were determined by spectroscopic evidences. The structures of 1 and 2 were further confirmed by single-crystal X-ray diffraction studies. Compound 2 exhibited significant α-glucosidase inhibitory and antibacterial activities against Escherichia coli and Bacillus subtilis. 相似文献
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Shaoping He Si Li Muhammed Adebayo Arowolo Qifang Yu Fu Chen Ruizhi Hu Jianhua He 《Animal Science Journal》2019,90(3):401-411
This study investigated the effect of dietary resveratrol supplementation on growth performance, rectal temperature, and serum parameters of yellow‐feather broilers under heat stress. A total of 480 yellow‐feather broilers (28‐day‐old) were randomly allotted to five groups with six replicates. A thermoneutral group (TN) (24 ± 2°C) received a basal diet and another four heat‐stressed groups (37 ± 2°C for 8 hr/day and 24 ± 2°C for the remaining time) were fed the basal diet or basal diet with 200, 350, and 500 mg/kg resveratrol for 14 consecutive days. The results revealed that resveratrol supplementation improved average daily gain (p = 0.001), and decreased (p < 0.05) rectal temperature from d 3 when compared with heat‐stressed group without resveratrol. In addition, supplementation with resveratrol at 350 or 500 mg/kg lowered (p < 0.05) the contents of corticosterone, adrenocorticotropic hormone, cholesterol, triglycerides, uric acid, malonaldehyde, and activities of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase, increased (p < 0.05) the levels of triiodothyronine, the ratio of triiodothyronine to thyroxine, total protein, glutathione, and activities of alkaline phosphatase, total superoxide dismutase, catalase, and glutathione peroxidase, though with few fluctuation. In conclusion, supplementation with resveratrol can improve the growth performance by positively regulating serum metabolic parameters and alleviating tissue oxidant damage of broilers under heat stress. 相似文献
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María?C.?Mateo-SánchezEmail author Aitor?Gastón Carlos?Ciudad Juan?I.?García-Vi?as Jorge?Cuevas César?López-Leiva Alfredo?Fernández-Landa Nur?Algeet-Abarquero Miguel?Marchamalo Marie-Josée?Fortin Santiago?Saura 《Landscape Ecology》2016,31(6):1261-1276