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41.
He Jing-lei Zhou Yan-tong Kong Ling-ze-lai Li Bing Yu Jin-qiu Gong Hao Sun Xue Cui Guo-wen 《东北农业大学学报(英文版)》2021,28(2):69-76
In order to reveal the effects of different altitudes on the nutritional quality of wild forage in Qinghai-Tibet Plateau,this study used Elymus nutans as the tested plants to evaluate the changes of nutrient contents and the correlation between the nutrient contents and altitudes.Four sampling sites were set up at altitudes of 2 562,2 660,2 775 and 2 905 m with the vertical distance among each sampling point was about 100 m.The results showed that the crude protein,ash and phosphorus contents of Elymus nutans decreased significantly with an increase in altitudes.The crude protein contents decreased by 1.87 % with each 100 m increase in altitudes.The variation rule of crude protein contents with altitudes in the simulated curve was "y=–0.0187x+63.244 (R~2=0.9557)".The crude ash contents decreased by 1.77% with each 100 m increase in altitudes.The variation rule of crude ash contents with altitudes in the simulated curve was "y=–0.0177x+56.144 (R~2=0.978)".Neutral detergent fiber (NDF) and acid detergent fiber (ADF) showed an overall increasing trend with the increase of altitudes,but the most obvious increase was at 2 775 m.The contents of crude fat and Ca did not change regularly with altitudes. 相似文献
42.
通过对福建省德化县早熟砂梨“黄叶病株”及“正常植株”叶片及土壤的营养诊断分析:黄叶病株叶片平均含镁量0.131%,极显著低于正常植株0.328%;黄叶症较重的果园土壤交换态镁含量低12.6~24.5㎎/㎏及土壤酸性强pH3.6~4.5,诊断结论砂梨叶片黄化现象为镁素缺乏所致。矫治试验效果,叶面喷施1%硝酸镁3次,可以叶色转绿;12月份土壤基施钙镁磷肥株1.3 kg,翌年5月份后有明显矫治效果。 相似文献
43.
44.
稻粉虱Aleurocybotus indicus David et Subramaniam, 属半翅目粉虱科, 以刺吸式口器为害水稻叶片而导致产量损失, 是我国闽?赣?浙等稻区的一种偶发性水稻害虫, 近20多年已鲜有报道, 但2019年-2021年在中国水稻研究所富阳试验农场稻田暴发?本文描述了稻粉虱的为害症状和形态特征, 并配以原色照片; 克隆得到了稻粉虱线粒体DNA COⅠ基因片段, 发现其与烟粉虱Bemisia tabaci序列一致性最高(85.80%); 田间调查表明, 富阳试验农场及周边稻田稻粉虱均有不同程度的发生, 但前者发生量明显较高(每个分蘖最高可达251头), 推测可能与农场温室内的稻粉虱越冬虫源有关; 利用稻苗浸渍法评估了不同作用机制的7种杀虫剂对稻粉虱的毒力, 发现双丙环虫酯?氯虫苯甲酰胺?氟啶虫胺腈?氟啶虫酰胺和溴氰虫酰胺对稻粉虱成虫均有较好的杀虫活性, 其中前4种药剂推荐中剂量处理后72 h的校正死亡率均可达100%, 其LC50分别为3.028?3.769?6.405 mg/L和7.894 mg/L?本研究可为我国稻粉虱的识别诊断和化学防治提供重要依据? 相似文献
45.
V. Martini A. Poggi F. Riondato M. E. Gelain L. Aresu S. Comazzi 《Veterinary and comparative oncology》2015,13(3):281-287
Histopathology and immunohistochemistry are mandatory to solve the differential between canine low‐grade lymphoma and reactive hyperplasia. However, clinicians and owners often show reluctance toward these invasive tests. However, molecular biology techniques are still not sensitive and specific enough to be regarded as a reliable tool for final diagnosis. In humans, flow cytometry (FC) allows a definitive diagnosis of T‐cell lymphoma based on high prevalence of antigen aberrancies. We describe here the immunophenotype of 26 cases of suspect canine small‐clear cell lymphoma, determined by multi‐colour FC. All cases showed antigen aberrancies and therefore neoplasia was always confirmed. As a consequence, we argue that the combined use of cytology and FC allows solving the differential diagnosis between small clear cell lymphoma and non‐neoplastic reactive conditions when histopathology is not available. Further studies are needed to establish if any aberrancy can be considered indicative of specific histotypes. 相似文献
46.
47.
为弄清贵州某野生动物园长臂猿死亡的原因,本试验采用流行病学调查、临床症状观察、病理剖检诊断和RT-PCR检测确诊等方法,对该野生动物园发病长臂猿进行了诊断。试验结果显示,流行病学调查、剖检病理初步诊断该野生动物园长臂猿疑似流感病毒、支原体和细菌混合感染,RT-PCR/PCR检测确诊发病长臂猿为流感病毒、支原体混合感染,细菌分离培养、生化特性鉴定和动物致病性试验确诊为多杀性巴氏杆菌感染。结果表明造成该野生动物园长臂猿发病死亡的原因为流感病毒、支原体和多杀性巴氏杆菌混合感染。根据诊断及药敏试验结果,制定出了免疫预防及治疗措施。 相似文献
48.
Fumiko SUZUTA Kumiko KIMURA Ryo URAKAWA Yukio KUSUDA Shogo TANAKA Yasuko HANAFUSA Makoto HARITANI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):1029-1031
This report presents a new case of mucormycosis encountered in penguin characterized by morphological variation of hyphae and presence of sporangia with numerous sporangiospores. A 4.5-year-old Magellanic penguin (Spheniscus magellanicus) died after exhibiting anorexia, poor nutritional condition and dyspnea. Multiple nodular lesions were observed in the thoracic and abdominal regions. Histopathologically, hyphae of various sizes were seen in the lungs, air sac and nodular lesions. Myriad sporangiospores and several sporangia were observed in/around the bronchi or parabronchi. The very narrow and short hyphae in the nodules were not consistent with the characteristics of Mucorales. However, for most hyphae, including those in the nodules, sporangiospores and sporangia, immunohistochemistry revealed Mucorales-positive reactions. In addition, these fungi were identified as Rhizomucor pusillus by gene
analysis. 相似文献
49.
Rieko OKAME Keiko NAKAHARA Noboru MURAKAMI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):815-821
We measured the plasma levels of amino acids at various reproductive stages in female
rats, including the estrous cycle, pregnancy and lactation, and compared the resulting
amino acid profiles using two- or three-dimensional figures. These figures revealed that
the amino acid profiles of pregnant and lactating dams differed considerably from those
during the estrous cycle or in male rats. The plasma levels of individual amino acids were
almost the same between proestrus, estrus, metestrus and diestrus, and their profiles did
not differ significantly. However, the amino acid profiles changed during pregnancy and
lactation in dams. The plasma Ser level decreased significantly in mid and late pregnancy,
whereas Tyr, Gly and His decreased significantly in the late and end stages of pregnancy,
and Trp and Lys significantly decreased and increased at the end of pregnancy,
respectively. Much larger changes in amino acid profiles were observed during lactation,
when the levels of many amino acids increased significantly, and none showed a significant
decrease. Plasma Pro, Ser and Gly levels increased continuously from day 1 until day 15 of
lactation, whereas Asn and Met increased significantly from days 1 and 5 respectively
until the end of lactation. These results suggest that the profiles of plasma amino acids
show characteristic changes according to reproductive stage and that it may be necessary
to consider such differences when performing amino acid-based diagnosis. 相似文献
50.
Megumi ITOH Yoshie SAKURAI Yasuhiro NAKAJIMA Satoshi KAWAMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1655-1657
The association between blood calcium levels and electrocardiographic variables was
compared in 137 normal parturient and 36 peripartum recumbent Holstein cows to determine
whether hypocalcemia in peripartum dairy cows can be rapidly diagnosed using
electrocardiograph. Inverse of STc (ST peak interval/SS interval0.5) and blood
ionized calcium or serum calcium concentrations were strongly correlated, and both
correlation coefficients were 0.81 (P<0.001). The 95% prediction
interval indicated that cows with STc >0.385 ± 0.001 sec are very likely to be
hypocalcemic (blood ionized or serum calcium concentrations of <0.9
mmol/l or <7.5 mg/dl, respectively). These findings
indicate that hypocalcemia in parturient cows can be non-invasively estimated using the
STc. 相似文献