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排序方式: 共有1048条查询结果,搜索用时 15 毫秒
31.
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
32.
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
33.
Kyoji Hagiwara Takahiko Higashi Kazunari Takahashi Naho Hara Hideyuki Aoki Naoyuki Miyazaki Qing-Yu Wang Yafeng Zhu Osamu Yatou Hiroshi Tanaka Toshihiro Omura 《Journal of General Plant Pathology》2006,72(3):186-189
Transencapsidation of the Rice gall dwarf virus (RGDV) inner core by the Rice dwarf virus (RDV) outer capsid P8 protein was examined in vitro and in planta. When RGDV core particles were incubated with an extract
from RDV P8-transgenic rice leaf tissue, RDV P8 encapsidated the RGDV core particles to form double-shelled virus-like particles
in vitro. In contrast, when RDV P8-transgenic rice plants were inoculated with RGDV, progeny RGDV particles contained RGDV
P8 but RDV P8 was not detectable in the virions. No significant differences were found in acquisition by the vector insects
and subsequent transmission rates between RGDV infecting nontransgenic rice plants and those infecting RDV P8-transgenic rice
plants. These results indicate that mechanisms of and/or requirements for interactions between P8 and the inner core particles
of phytoreoviruses differ between in vitro and in planta. 相似文献
34.
The timing of parturition was recorded for a total of 56 beef cattle (Japanese Black × Holstein Friesian) on different dietary treatments. The rate of calving during daylight hours in cows night‐fed (18.00 hours) with a roughage diet was significantly higher than that in cows night‐fed with a high concentrate diet (79.2% vs 38.5%, P < 0.05). Subsequently, the vaginal temperature (VT) of these cows was analyzed using a cosinor method. When the feeding schedule was changed from twice daily (08.30 and 15.30 hours) to night feeding, the periodicity, the acrophase and the bathyphase, which were the parameters of the cosine curve, were unstable from the first day of night feeding until after day 6 (P < 0.05). Prior to parturition, the midline‐estimating statistic of rhythm (MESOR) and the amplitude for the cows that were fed a high‐roughage diet at night and that calved at night‐time were lower and larger, respectively, than that for the other treatments (P < 0.01). Based on these results, the time of parturition in most of the beef cows was influenced by feeding time and diet composition. Those cows that calved at night‐time in spite of night feeding had lower vaginal temperatures. 相似文献
35.
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
36.
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
37.
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
38.
Osamu Yamato Eun-Og Jo Toru Shoda Masahiro Yamasaki Yoshimitsu Maede 《Journal of veterinary diagnostic investigation》2004,16(5):469-472
This report describes a rapid and simple method for mutation screening of G(M1) gangliosidosis in Shiba dogs by direct amplification of DNA from canine whole-blood specimens using a novel polymerase chain reaction (PCR) reagent cocktail, which can eliminate the DNA extraction process and amplify the genomic DNA directly from human or murine whole blood. The strategy of this mutation screening is based on the identification of a nucleotide deletion by restriction enzyme analysis, coupled with the direct PCR amplification. The target sequence of the canine beta-galactosidase gene could be amplified directly from various forms of canine whole-blood specimens, including anticoagulated blood, blood stored frozen for 1 year, dried blood held in filter paper for 1 year at room temperature, and dry powder of blood stripped from Giemsa-stained blood films, which had been prepared 10 years earlier, resulting in the determination of genotypes in all the specimens. This method simplified the molecular diagnosis and carrier screening of G(M1) gangliosidosis in Shiba dogs, making it simple to examine specimens from the large, widely distributed population of these dogs. 相似文献
39.
Isao Sawaguchi Shunji Shimizu Kouichi Ichihara Katsumi Toyokawa Osamu Ohkawabata 《Journal of Forest Research》1997,2(1):15-19
The growing condition of afforestation trees and damage to lower-story trees caused by felling and hauling of upper-story
trees in a multi-storied forest in Peninsular Malaysia was surveyed. Seventy months have passed since the planting ofAcacia mangium upperstory trees, which have grown 233 m3/ha in volume. The growth ofShorea leprosula thirty-five months after planting of lower-story trees have reached 5.54 m in height. However, as the ratio of height to
basal diameter exceeds 100:1, trees are tapering to a considerable degree. A backhoe was installed in order to fell the upper-story
trees. From the results of logging, the damage ratio estimation of the lower-story trees was simulated by using the Monte
Carlo method. The damage ratio differed considerably depending on planting patterns, height of upper-story trees and felling
skills. The results of this survey proved that the felling and hauling of upper-story trees would be technically feasible
in the future, except when one row upper-story trees and one row lower-story trees method were employed. 相似文献
40.
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