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91.
92.
Hydrus-1D模型在田间水循环规律分析中的应用及改进 总被引:9,自引:4,他引:5
为分析农田水分运移规律,以华北平原位山引黄灌区典型田间为研究对象,应用Hydrus-1D模型连续模拟了 2006-2009年的田间水分运移过程。对模型中表面阻抗的计算方法进行了改进,从而改善了蒸散发的模拟结果,与涡度相关系统的实测蒸散发数据对比表明了改进的合理性。对蒸散发的分析表明,对于种植季节性作物的农田,叶面积指数(leaf area index,LAI)是影响蒸散发季节变化过程的重要因素,而气象条件主要决定其在较短时间尺度(如一周)内的波动。与时域反射仪(time domain reflectometry,TDR)实测土壤含水率的对比表明,模型对土壤含水率的模拟精度较高。水量平衡分析结果表明,降雨和灌溉的80%由蒸散发消耗,在汛期农田通过排水发生田间渗漏损失。 相似文献
93.
To assess the effects of negative and positive behaviors on milk yields, this study examined the attitudes and behaviors of stockpersons toward their cows and milk yields at a farm where 15 workers milked 67 cows as rotating shift work. At a holding area when moving cows to the parlor, stockperson behaviors were observed at 34 milkings. Behaviors were classified as negative (NEG) or positive (POS): NEG were attempts to move cows using touching (NT), vocalization (NV), and gestures (NG); POS were communications without attempting to move cows, consisting of touch (PT) or vocalization (PV). Numbers of NV and NEG were negatively correlated with milk yields of first parity (p < .05). Average milk yields of first parity and all cows were higher when PT were observed (p < .001, p < .0001) and POS were observed (p < .001 and p < .0001). Numbers of PT were positively correlated with milk yields of first parity (p < .05). Average milk yields of second parity were higher when PV was observed (p < .01). Positive behaviors, especially touching, are related to higher herd milk yields. Negative behaviors such as negative vocalizations are related to lower yields of younger cows. 相似文献
94.
95.
日本奶牛的饲养主要依赖于国外饲料的进口,国际饲料价格的上涨使得日本奶业陷入了危机,奶农的生产经营状况直接关系到奶业产业的发展。本研究基于日本社团法人中央畜产会实施的全国农户生产经营指导项目中所调查的294个奶农农户的生产经营相关数据,采用因子分析、多元线性回归分析、聚类分析方法,对影响奶农经营收入的因素进行了分析。结果表明,奶牛饲养的收益、奶牛饲养的劳动效率、饲养规模这三个因素对奶农的生产影响最大;阐明了奶农生产中存在的问题;提出了奶农生产经营的改善应该着重于适度扩大生产规模;合理进行投资,并且均衡大型机器设备和小农器具投资的比例以改善奶农饲养效率以及饲料生产效率,提高奶农的收入。最后,借鉴日本奶业生产经营中存在的问题,总结了对我国奶业发展的启示。 相似文献
96.
Mio KOBAYASHI Toshinori YOSHIDA Risako YAMASHITA Ryo ICHIKAWA Junta NAKAHARA Kazuki NAKAMURA Hiromu OKANO Yasunori TAKAHASHI Nanao ITO Makoto SHIBUTANI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(6):994
We encountered a case of cutaneous squamous cell carcinoma (SCC) in a 17-year-old female koala at a zoo. A fragile, papillary, elevated mass was found on the third digit of the right hind limb. SCC was identified histopathologically: squamous cell-like polygonal tumor cells showed a nest-like growth pattern with epidermal down growth, central keratinization and necrotic foci, and invaded dermal connective tissues. Metastatic lesions were observed in various organs, including the lung and axillary lymph node: in the lung, multiple metastatic foci similar to the primary lesion, and in the axillary lymph node, individual polygonal tumor cells infiltrated the sinusoids. Immunohistochemistry revealed that the tumor cells were positive for proliferating cell nuclear antigen, which exhibited 32–33% of labeling indices in the tumor cells. To our knowledge, this is the first report of a case of SCC in a digit of a koala. 相似文献
97.
Teruo SANO Tetsuya KOBAYASHI Akira ISHIGURO Yoshie MOTOMURA 《Journal of General Plant Pathology》2000,66(1):68-70
Grapevine yellow speckle viroid 1 (GYSVd 1) was first detected in Japan from commercial grapevines. The viroid seems to be
spreading in Japanese commercial vineyards but without causing noticeable disease symptoms. Two Japanese GYSVd 1 isolates
from the cultivars Campbell and Steuben were sequenced. The Campbell isolate is included in the type 2 variant of GYSVd 1,
and the Steuben isolate is included in the type 3. Both of the isolates were grouped into the yellow speckle-inducing variants
in the nucleotide sequence ; however, the etiological importance of this viroid on the viticulture of Japan has not yet been
determined.
Received 14 June 1999/ Accepted in revised form 25 August 1999 相似文献
98.
A cat with acute myeloblastic leukemia without maturation (M1) treated with combination chemotherapy
Mashita T Shimoda T Yoshioka H Takahashi Y Mitsuda M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(1):97-101
A 2-year-old domestic shorthair cat was presented to us with decreased activity and anorexia. Hematologic findings revealed a mild non-regenerative anemia, thrombocytopenia, and leukocytosis with an increase in blast cells. Bone marrow aspirates also revealed a marked increase of blasts. The blastic cells were shown to be positive for peroxidase. Acute myeloblastic leukemia without maturation (M1) was diagnosed according to the FAB classification. Chemotherapy was initiated with cyclophosphamide, vincristine, prednisolone, and cytosine arabinoside. The cat responded partially. In total, the cats were given 7 blood transfusions. The cat died 14 weeks after first being presented to us. 相似文献
99.
Taiki KIDA Arisa YAMAZAKI Koji KOBAYASHI Tatsuro NAKAMURA Takayuki NAKAGAWA Ryohei NISHIMURA Takahisa MURATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(5):644
Polyunsaturated fatty acids, including arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA), are converted to hundreds of lipid mediators by cyclooxygenases (COX), lipoxygenases (LOX), and cytochrome P450 (CYP), or through non-enzymatic processes, and they reflect inflammatory states of the body. We comprehensively analyzed lipid metabolites in dog urine using a liquid chromatograph-mass spectrometry (LC-MS/MS) to describe their metabolic characteristics. We detected 31 AA-derived metabolites, four EPA-derived metabolites, and a DHA-derived metabolite in all urine samples. Among AA-derived metabolites, 15, 5, 3, and 8 were generated by COX, LOX, CYP, and non-enzymatic oxidation respectively. This study will be the first step to use profiles of urinary lipid metabolites for better understanding and diagnosis of canine diseases. 相似文献
100.
Kyohei Yasuno Masako Imaoka Tetsuya Ohsawa Keiko Okado Kiyonori Kai Yoshimi Tsuchiya 《Journal of toxicologic pathology》2022,35(4):345
Inflammation of the cardiac coronary artery in ICR mice is occasionally observed in toxicity studies; however, this has not been well explored histologically. Herein, we investigated the detailed histology of the associated lesions in 6–8-week-old ICR mice. Coronary artery inflammation in the right ventricular wall was observed in 10 of 142 mice (7.0%). Histopathological examination revealed hypertrophy of the vascular smooth muscle cells and perivascular infiltration of macrophages in mild cases. In moderate to marked cases, single-cell necrosis of vascular smooth muscle cells, hemorrhage of the tunica media, and fibrinoid necrosis of the vessel wall were observed, in addition to the changes seen in mild cases. Electron microscopic examination of moderate cases revealed a discontinuous internal elastic lamina suggestive of rupture, and vascular smooth muscle cells beneath the elastic lamina showed degeneration and necrosis. These findings suggest that the lesions developed as a rupture of the internal elastic lamina and necrosis of vascular smooth muscle cells, while leaked plasma components caused vascular and perivascular inflammation. In ICR mice, dystrophic calcinosis (DCC) is known to occur rarely in the right ventricle. DCC is defined as focal calcification in necrotic myocardial fibers, the pathogenesis of which is considered to involve ectopic calcification. Since calcification was not observed in any part of the heart, including the inflammation region, the pathophysiology of cardiac arterial inflammation seen in our ICR mice was considered to differ from that of DCC. 相似文献