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91.
Sato M Goto-Koshino Y Kanemoto H Mochizuki H Fujino Y Ohno K Tsujimoto H 《Veterinary immunology and immunopathology》2011,140(1-2):166-169
BCL6 is known to be a key molecule in germinal center (GC) formation of lymph nodes, and its expression profiles have been implicated in the prognosis of diffuse large B-cell lymphoma in humans. The present study was carried out to characterize canine BCL6 cDNA and to indicate the technical methods for detection of the BCL6 protein in dog tissues. The deduced amino acid sequence of canine BCL6 showed close homology to that of human BCL6 (96.3%), especially in the zinc-finger motifs and POZ (poxvirus and zinc finger) domain with complete identity. Immunoblot analysis of a canine lymph node with an anti-human BCL6 monoclonal antibody revealed a band of 80 kDa. Immunohistochemical staining using the same antibody produced positive reactions in the cells exclusively localized in the GC of a canine lymph node. This study will be useful for the molecular classification of canine B-cell lymphomas with different prognoses. 相似文献
92.
93.
Abstract A method for assaying the soil lipase activity is described. It involves the titrimetric estimation of the amount of lauric acid released by the lipase activity when the soil is incubated with Tween 20 in the presence of toluene at 30°C for 18 h under agitation. The method is simple and precise and incubation without agitation is also possible. The method has been applied to six different kinds of soils. The lipase activity in the cultivated soils ranged from 22.5 to 75.5 mmol min?1 g?1 of dried soil. The K m value for Tween 20 was 1.8 × 10?4 m. The optimum pH was approximately 7.5. The hydrolysis of liveen 20 in soil was inhibited by glycerol which was the essential moiety of glyceride. The inhibition by glycerol was found to be competitive. These results indicate that Tween 20 is a potential substrate for the assay of the glyceride hydrolytic activity in soils. 相似文献
94.
Abstract Soil protease is an important enzyme in the nitrogen cycle which plays an essential role in the growth of various crops. We have attempted to identify a microbial source of soil protease. Selective soil incubation using antibiotics was suitable for a rough estimation of the groups of microorganisms responsible for the production of soil protease (Hayano and Watanabe 1990; Hayano 1993). Enumeration of proteolytic microorganisms in the field and analysis of their protease-producing ability enabled to evaluate the potential of various soil microorganisms for soil protease production (Watanabe and Hayano 1993a; Watanabe et al. 1994). For the accurate estimation of the soil protease source, the characteristics of the soil protease and microbial protease must be compared directly based on enzymatic properties as indices. 相似文献
95.
Tomoyuki Makino Syuichi Hasegawa Yasuhiro Sakurai Satoshi Ohno Hirokatsu Utagawa Yuji Maejima 《Soil Science and Plant Nutrition》2013,59(3):581-590
Abstract The changes in the exchangeable Mn (Ex-Mn), exchangeable Co (Ex-Co), and exchangeable Cu (Ex-Cu) contents by air-drying of soils were reported in our previous paper. The drying effect, however, was not analyzed in the field. The objective of this study was to investigate the influence of soil-drying under field conditions on Ex-Mn, Ex-Co, and Ex-Cu levels. Two paddy soils (Tsukuba and Yawara) were collected at four different soil depths (0?1, 1?5, 5?10, and 10?20 cm) under three different soil moisture conditions i.e., after harvest, after successive sunny days and after rainy days. After sunny days, Ex-Mn and Ex-Co contents in the surface soil layer markedly increased and drastically decreased after rainfall, while they remained almost unchanged in the lower soil layers. Ex-Cu contents slightly increased in the surface soil layer after sunny days. A similar tendency was observed in soil column experiments. The contents of Ex-Mn, Ex-Co, and Ex-Cu increased 12, 12, and 2 times in the upper layer of soil columns that had been sampled from the Yawara field and stored in a dark room for 8 d. The increase of the Ex-Mn and Ex-Co contents in the upper layer could not be explained by the capillary rise of soil water from the lower layers of the columns. In a soil-drying experiment under laboratory conditions, Ex-Mn and Ex-Co contents began to increase when the water content of the Yawara soil was lower than 0.09?0.13 kg kg?1. The water content of the surface soil of the Yawara field after sunny days was 0.08 kg kg?1. Ex-Cu content did not change apprecially with the water content. It is concluded that the increase of the Ex-Mn and Ex-Co levels in field surface soils after sunny days can be ascribed to soil-drying. Some of the excess Ex-Mn and Ex-Co is expected to leach down into lower layers due to rain, which may contribute to plant uptake of Mn and Co. 相似文献
96.
Shimotori Koichi Yamamoto Haruki Imai Akio Kohzu Ayato Okamoto Takahiro 《Journal of Soils and Sediments》2021,21(2):1222-1231
Journal of Soils and Sediments - Sediment oxygen demand (SOD) measurement currently requires a long preparation time and bulky experimental equipment, which represent major obstacles to conducting... 相似文献
97.
Shigeya Maeda Toshihiko Kawachi Koichi Unami Junichiro Takeuchi Tomoki Izumi Syunsuke Chono 《Paddy and Water Environment》2009,7(3):163-175
A fuzzy optimization model is developed to allocate allowable total nitrogen (T-N) loads to distributed nonpoint sources (NPSs)
and point sources (PSs) in a watershed for river water quality management using the linear programing technique. The watershed
is divided into uniform grid cells on which T-N loads issuing from NPSs such as paddy fields, upland crop fields and cities
are controlled. A geographic information system integrated with the digital elevation model facilitates computation of route
lengths of surface and subsurface flows from cells to a river running through the watershed. The T-N loads discharged from
their sources are assumed to decay, subject to distance-related first-order kinetics. As management goals, maximizations of
total allowable NPS loads, total allowable PS loads and total yield of rice are considered from environmental and economic
viewpoints. A prime constraint is an effluent limitation standard for the aggregate amount of loads that arrive at the downstream
end of the river. The fuzzy sets theory helps appropriately describe vague attitudes of decision-makers (i.e., stakeholders
and management authorities) in terms of constraints and conflicting goals. An application of the fuzzy optimization model,
developed as an improvement over our last nonfuzzy model, to a real watershed in Shiga prefecture, Japan, demonstrates that
the fuzzy model embodies our last model, and is capable of creating management alternatives for T-N load allocation in a more
practical and flexible manner. 相似文献
98.
Junichiro Takeuchi Toshihiko Kawachi Koichi Unami Shigeya Maeda Tomoki Izumi 《Paddy and Water Environment》2009,7(1):33-43
A cell-based distributed watershed model is developed which enables us to simulate the hydrological and hydraulic aspects
of the watershed in a refined fashion. With three-zoned cell profiling, the model is composed of three sub-models; tank model
for a surface water zone, soil moisture model for a surface soil zone, and unconfined shallow groundwater flow model for a
subsurface zone. Inclusion of the soil moisture sub-model modified to reroute the infiltration, routed from the tank sub-model,
into the return flow and the groundwater recharge features the model. The groundwater flow sub-model, numerically approximated
by use of the finite volume method and the implicit time-marching scheme, considers a network of on-farm drainage canals as
internal boundaries, which is an essential need for modeling the watershed including farmlands. Cascade-linking of the three
sub-models in a cell and assembling of all the cells over the entire watershed domain provides the global equations system
to be solved. Applicability of the model is demonstrated with its practical application to a real watershed in that paddy
and upland crop fields take great part of the land-use practice. It is then indicated in a quantified manner that rice farming
significantly contribute as a major groundwater recharger in an irrigation period to fostering and conservation of regional
water resources. Along with appropriately profiling a cell, the model is so versatile and tough that it can be applied without
difficulty to a watershed of diverse terrains and land-uses and the computations can stably be carried out. It is thus concluded
that the model presently developed could be a powerful “watershed simulator” to investigate and assess the time-varying hydro-environmental
properties of a watershed while separating and integrating the hydrological and hydraulic components of particular importance. 相似文献
99.
Hagiwara Y Fujiwara S Takai H Ohno K Masuda K Furuta T Nakayama H Doi K Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(3):349-351
Pneumocystis carinii pneumonia was diagnosed by postmortem examination of a one-year-old Cavalier King Charles Spaniel with four-week history of dyspnea. Cytologic and histologic examination of lung tissues revealed numerous P. carinii trophozoites and cysts, and P. carinii specific DNA was detected by polymerase chain reaction. The dog showed hypogammagloblinemia and extremely low levels of serum IgG. It was considered that P. carinii pneumonia in this case was associated with an immunodeficient condition which has already been reported in Miniature Dachshunds. 相似文献
100.
Maeda S Mizuno T Yamashita K Kurata K Masuda K Ohno K Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(9):1035-1038
Thymus and activation-regulated chemokine (TARC) is known as a functional ligand for CC chemokine receptor 4 (CCR4), which is selectively expressed on Th2 lymphocytes and induces selective migration of the cells to allergic lesions. In this study, we cloned canine TARC cDNA from canine thymus by RT-PCR with rapid amplification of cDNA ends (RACE) method. The canine TARC clone contained a full-length open reading frame encoding 99 amino acids and included four cysteine residues characteristic to CC chemokine family. The canine TARC cDNA showed 77.5%, 67.4%, and 68.5% amino acid sequence similarity with human, mouse and rat homologues, respectively. Expression of TARC mRNA was detected not only in thymus but also in spleen, lymph node, lung and heart of the various normal dog tissues examined. TARC cDNA clone obtained in this study will be useful for further investigation on allergic diseases in dogs. 相似文献