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排序方式: 共有678条查询结果,搜索用时 218 毫秒
21.
Suzuki K Kato T Tsunoda G Iwabuchi S Asano K Asano R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(12):1173-1175
The effect of 1.35% isotonic sodium bicarbonate solution (ISB) administered intravenously on acid-base equilibrium was examined in 18 acidemic Japanese black beef calves with spontaneous diarrhea. The infusion volumes of ISB were decided based on the first half volumes of base needed. In 72.2% (13/18) of calves, improvement of acidemia was detected. There was good correlation (r=0.693, p<0.01) between infused volume of ISB and changes in base excess (y=1.097x + 4.762). Infusion volumes of ISB were 7.5, 10.2, 12.9 and 15.7 ml/kg, respectively, enough to correcting the first half of 5, 10, 15 and 20 mEq/l of base deficit in acidemic calves. Our finding suggested that ISB could be used to correct metabolic acidosis without altering electrolyte concentrations in calves. 相似文献
22.
Optimal application timing of simeconazole granules for control of rice kernel smut and false smut 总被引:1,自引:0,他引:1
Mikio Tsuda Masashi Sasahara Toshiaki Ohara Shigehiro Kato 《Journal of General Plant Pathology》2006,72(5):301-304
We investigated the optimal timing of simeconazole (RS-2-(4-fluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-3-trimethylsilylpropan-2-ol) application for controlling rice kernel smut in field trials in Miyagi Prefecture,
Japan, using formulations of simeconazole (1.5% granules). The field tests revealed that a submerged application of simeconazole
granules (450–600 g ai/ha) at 1–5 weeks before heading was highly effective against kernel smut, with treatments 1–2 weeks
before heading being the most effective. Submerged application of the fungicide at 2–5 weeks before heading was also highly
effective against false smut, with treatment 3 weeks before heading being the most effective. These periods overlap the timing
for optimal application of simeconazole to control rice sheath blight and ear blight. Consequently, we concluded that treatment
with simeconazole 2–3 weeks before heading can be a useful tool for controlling all four diseases. 相似文献
23.
Production of inter-section hybrids between Primula filchnerae and P. sinensis through ovule culture
Inter-section hybrids were obtained in the reciprocal crosses between Primula filchnerae (2n = 2x = 24) of Sect. Pinnatae and P. sinensis ‘Fanfare’ (2n = 2x = 24) of Sect. Auganthus by rescuing ovules on half-strength (1/2) Murashige and Skoog's (MS) medium supplemented with 50 g l−1 sucrose, 2.5 g l−1 gellan gum, 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 0.1 mg l−1 6-benzyladenine (BA) and 50 mg l−1 gibberellic acid (GA3). In ovule culture, germination occurred with radicle elongation but no plumule was observed. The radicle kept on the initial medium showed root proliferation with callus formation. When the calluses were transferred to (1/2)MS media containing 30 g l−1 sucrose and 3 g l−1 gellan gum, without plant growth regulators (PGRs) or with 1 mg l−1 zeatin and 0.1 mg l−1 NAA, plantlets were regenerated. The plants thus obtained were confirmed to be hybrids through flow cytometry (FCM) and random amplified polymorphic DNA (RAPD) analyses. The hybrid obtained when P. filchnerae was used as the maternal parent was diploid, whereas hexaploid hybrid was obtained when using P. sinensis as the maternal parent. The hexaploid hybrid might be produced through chromosome doubling of a triploid originated from the fertilization of P. sinensis with unreduced pollen of P. filchnerae. 相似文献
24.
Abstract – Many studies have reported that prey fish increase in body size with an increase in piscivore abundance, and this change may be explained mainly by two processes: release from intraspecific competition because of a reduction in the prey fish population and size-dependent selection by the piscivore. However, the evolutionary mechanism is not yet fully understood. Here, we first show the body-size dynamics of the semelparous gobiid fish Gymnogobius isaza , which is one of the prey fishes of the introduced largemouth bass, Micropterus salmoides . The data show the possibility that the goby body size might have changed in parallel to the number of largemouth bass from 1975 to 2002, which may be one of the best examples of the positive relationship between body size and predation rate. Furthermore, we explored a mathematical model to consider a body-size change of semelparous fish from an evolutionary viewpoint. The model provided the following qualitative predictions: (1) the optimal assimilation rate increases with predation pressure; (2) a rapid large-scale increase in predation pressure may exterminate the prey fish because of delayed evolution of the assimilation rate; and (3) the optimal assimilation rate increases when the prey fish is more likely to die through predation than through natural mortality or when it is difficult to grow larger because of low resource availability or insufficient foraging efficiency. Moreover, we propose a theoretical framework to evaluate the relative effects of ecological and evolutionary processes over the long term. 相似文献
25.
The effect of an intravenous injection of acetate on plasma insulin and glucagon concentration was examined in conscious sheep. Sodium acetate (312 to 5000 mumol kg-1 bodyweight) injection increased plasma insulin concentrations in a dose-dependent manner. Plasma glucagon concentration was not affected by doses up to 1250 mumol kg-1. Doses of 2500 and 5000 mumol kg-1 produced significant increases (P less than 0.05), but not in a dose related manner. The results of this study indicate that the receptive mechanism of the A cell in the sheep pancreas to acetate might be different from that of the B cell. 相似文献
26.
Kazumasa Yoshida Mitsuru Nishiguchi Shojiro Hishiyama Atsushi Kato Koetsu Takahashi 《Journal of Wood Science》2006,52(4):372-375
Sugi (Cryptomeria japonica D. Don) produces secondary metabolite norlignans in xylem. Several norlignans are involved in the coloration of heartwood
and defense of sapwood against microbial invasion. Their biosynthetic process should be well understood so that their properties
can be exploited to improve the quality and utility of C. japonica wood. Unfortunately, information on the norlignan biosynthesis is limited because norlignans are mainly synthesized in a
particular season in the transition zone (TZ) along with the heartwood formation, and is difficult to study. Although the
generation of two norlignans of C. japonica, agatharesinol and (E)-hinokiresinol, has been reported, systems for producing other norlignans are not yet known. To establish a novel norlignan
generating system, we examined the changes occurring in norlignans in a TZ during the process of drying a C. japonica log. On the day of felling, the TZ contained agatharesinol and (E)-hinokiresinol, which increased until they reached a maximum on day 40 after felling. Sequirin-C appeared on day 40 and increased
to day 70. The generation of sequirin-C in the TZ can be used to investigate the biosynthetic process of heartwood norlignans.
This study describes for the first time the changes that occur in the composition of norlignan during the drying of the TZ. 相似文献
27.
Kazutaka Kato 《Journal of Forest Research》1997,2(2):75-78
To detect developmental differences inEpinotia granitalis in two host tree speciesCryptomeria japonica andChamaecyparis obtusa, the fourth or fifth instar larvae were collected daily from the two species located on the grounds of the National Forest
Tree Breeding Center, from April 19 to May 9 in 1994 and April 18 to May 10 in 1995. Larvae ofE. granitalis collected fromC. obtusa had heavier body weight, developed to larger adults than those collected fromC. japonica, and mortality from the fourth or fifth instar larval stage to adults onC. obtusa was lower than that onC. japonica. All these facts suggest that larval performance onC. obtusa was higher than that onC. japonica. 相似文献
28.
Understory individuals were found to form patches in a 100-year-old deciduous broad-leaved forest. The closed forest canopy
was uniform, and so the light conditions at various locations across the forest floor differed little after the leaf flush
of the overstory. To explain the distribution pattern in the understory, a hypothesis was proposed: in spring, the forest
floor is divided into patches according to the timing of leaf flush of the overstory individuals, and the light conditions
are more favorable for understory plants under the crowns of trees with later-flushing leaves. In the plot, three groups of
early, intermediate, and late, were recognized in the overstory concerning the timing of leaf flush. As for the start of leaf
flush, a difference of 31.6 days was recognized among tree species, and for the end of leaf flush, a difference of 40.3 days.
In the spring of 1998, the relative photosynthetic-photon-flux density under an intensively studiedCastanea crenata tree (late-flushing species) usually showed higher values than that under a similarly studiedAcer mono tree (early-flushing species). Analysis of the spatial-distribution pattern using Morisita’s1δ index revealed that the understory community had an aggregated distribution. In the overstory, the late- and the intermediate-flushing-species
groups showed aggregated distributions, while the early-flushing-species group showed random distribution. Spatial correlation
between the understory and the overstory was analyzed by using Morisita’sRδ index. The distribution of whole understory community spatially co-occurred with that of the late-flushing-species group
of the overstory. In contrast, the understory community was less developed below the members of the early-flushing-species
group of the overstory. We consider that the data presented here support our hypothesis, and we suggest that the growth and
survival of understory individuals were promoted in the places receiving light for long periods in spring. 相似文献
29.
Parasitism by parasitoid wasps on the larvae of Epinotia granitalis (Butler), which is a wood-injuring pest in coniferous plantations, was observed for 6 years in two plantation forests of
Chamaecyparis obtusa (Sieb. et Zucc.) Endl. and Cryptomeria japonica (L.f.) D. Don that were adjacent to each other and consisted of trees of almost the same size. E. granitalis larvae were collected from early April to mid-May, then reared in glass bottles, and finally examined to determine whether
or not the larvae had been parasitized. Five species of parasitoids were recorded; two of them were classified in Ichneumonidae,
Campoplex spp. A and B, and others in Braconidae, Iconella repleta Papp, Bassus cingulipes Nees von Esenbeck, and Bracon spp. In all 6 years, parasitism was first observed around 20 April. Species composition of parasitoids differed greatly among
years and between forests. In 1 year in each forest the percentage parasitism increased significantly with the sampling date,
indicating that not all parasitoids attack the same developmental stage of E. granitalis. The mean percentage parasitism per year was significantly higher in the forest of C. obtusa [11.5(%) ± 5.7(SD)] than in the forest of C. japonica (3.0 ± 4.1). These results suggest that the efficiency of parasitoid adults in finding hosts differed between the two forests.
Received: September 20, 2001 / Accepted: August 5, 2002
Acknowledgments We are grateful to Dr. K. Maeto, Shikoku Research Center, Forestry and Forest Products Research Institute, and to Dr. K.
Konishi, National Agricultural Research Center for Hokkaido Region, for identifying parasitoids, and to Dr. T. Miyaura, Forest
Tree Breeding Center, and Dr. H. Kosaka, Forestry and Forest Products Research Institute, for their helpful advice throughout
the study.
Correspondence to:K. Kato 相似文献
30.
Antibodies can swiftly provide therapeutics to target disease-related molecules
discovered in genomic research. Antibody engineering techniques have been actively
developed and these technological innovations have intensified the development of
therapeutic antibodies. From the mid-1990’s, a series of therapeutic antibodies were
launched that are now being used in clinic. The disease areas that therapeutic antibodies
can target have subsequently expanded, and antibodies are currently utilized as
pharmaceuticals for cancer, inflammatory disease, organ transplantation, cardiovascular
disease, infection, respiratory disease, ophthalmologic disease, and so on. This paper
briefly describes the modes of action of therapeutic antibodies. Several non-clinical
study results of the pathological changes induced by therapeutic antibodies are also
presented to aid the future assessment of the toxic potential of an antibody developed as
a therapeutic. 相似文献