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1.
The phylogenetic relationship among 30 accessions belonging to nine species of the genus Echinochloa Beauv. was studied on the basis of the sequence of three non-coding regions ( trn T-L, trn L-F intergenic spacers, and trn L intron) of chloroplast DNA (cpDNA). A strict consensus parsimonious tree of the three most parsimonious trees derived from 25 polymorphic sites (six indels and 19 substitutions) in the total sequences, ranging from 1715–1760 bp, represented five groups: (i) Echinochloa oryzicola Vasing. and Echinochloa stagnina Beauv. from Thailand; (ii) Echinochloa crus-galli Beauv. complex; (iii) Echinochloa crus-pavonis Schult; (iv) Echinochloa colonum Link. and Echinochloa frumentacea Link.; and (v) the African species, Echinochloa obtusiflora Stapf and Echinochloa stagnina . Japanese barnyard millet ( Echinochloa esculenta H. Scholz) and various weedy varieties of E. crus-galli and Echinochloa oryzoides Fritsch had quite similar sequences and formed the E. crus-galli complex, which was characterized by six substitutions. A cultivated form of E. oryzicola (Mosuo barnyard millet) and various morphological and agronomical forms of E. oryzicola were characterized by two indels. Indian barnyard millet ( E. frumentacea ) and its wild counterpart ( E. colonum ) were characterized by five substitutions. Domestication as millets and adaptation to paddy environments as mimic weeds might occur after the divergence of species in the Asian Echinochloa .  相似文献   
2.
The effect of intramammary injection of recombinant bovine granulocyte-macrophage colony-stimulating factor (rboGM-CSF, 400 microg/10 mL) on quarter milk levels of chemiluminescence (CL) activity, and somatic cell count (SCC) and shedding pattern of Staphylococcus aureus was investigated. Ten Holstein cows, naturally infected with S. aureus were used, with either early-stage or late-stage subclinical mastitis. Injection of rboGM-CSF caused a remarkable increase in milk CL activity with a peak at 6 h after the cytokine injection in the early- and late-stage groups. In the early-stage group, milk SCC stayed around preinjection level at 6 h, rose significantly on days 1 and 2, and was followed by a smooth and significant decline to an under preinjection level (below 200 000 cells/mL) on day 7 postinjection. Alternatively, in the late-stage group, milk SCC rose significantly at 6 h after the cytokine injection and maintained high levels thereafter. The milk S. aureus count decreased drastically by the cytokine injection in the early-stage group. The bacterial count was moderately decreased in the late-stage group, but increased back to preinoculation levels on day 7 after the cytokine injection. The results suggest that the rboGM-CSF has a potential as a therapeutic agent for S. aureus infection causing subclinical mastitis of dairy cows, if the cytokine is applied at the initial stage of infection.  相似文献   
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We isolated two pseudorabies virus (PRV) isolates (designated OT-1 and OT-2) from two hunting dogs exhibiting neurological manifestations after eating the flesh of wild boar hunted in Oita prefecture, Kyushu Island, Japan. The isolates corresponded to a previously reported PRV (MY-1 strain) isolated from a hunting dog in neighboring Miyazaki prefecture, and it clustered into genotype II based on the glycoprotein C sequence. Our results suggest that this common PRV strain may have been maintained in wild boars on Kyushu Island even though domestic pigs in this area have attained an Aujeszky’s disease-free status.  相似文献   
5.
OBJECTIVE: To investigate the relationship between myocardial performance index (MPI; also known as the Tei index) and cardiac function in anesthetized cats administered dobutamine. ANIMALS: 6 adult cats. PROCEDURES: Cats were anesthetized by administration of propofol (6 mg/kg, IV), and anesthesia was maintained by administration of isoflurane. Heart rate and systolic arterial pressure (SAP) were monitored. Stroke volume, cardiac output, and aortic blood flow (ABF) were measured by use of transesophageal ultrasonography. Left ventricular fractional shortening (LVFS), mitral E-wave velocity-to-A-wave velocity (E:A) ratio, and ejection time were measured by use of transthoracic echocardiography. Dobutamine was administrated via a cephalic vein at rates of 2.5, 5.0, and 10 microg/kg/min. RESULTS: Heart rate, SAP, cardiac output, and ABF increased with dobutamine administration, whereas stroke volume significantly decreased. The LVFS significantly increased, and the E:A ratio significantly decreased. Total isovolumic time and the MPI significantly decreased. The MPI was negatively correlated (r=-0.63) with LVFS. Conversely, the MPI was positively correlated with the E:A ratio (r=0.47), stroke volume (r=0.66), and total isovolumic time (r=0.95). However, the MPI was not significantly correlated with heart rate, SAP, cardiac output, or ABF. CONCLUSION AND CLINICAL RELEVANCE: Analysis suggested that the MPI provides a sensitive clinical assessment of cardiac response to medication in cats, which may be similar to the usefulness of the MPI reported in humans.  相似文献   
6.
The stem water conducting system of an evergreen broad-leaved oak, Lithocarpus edulis (Mak.) Nakai, was investigated. Evergreen broad-leaved oaks (Lithocarpus, Castanopsis, Cyclobalanopsis, Quercus) belonging to the Quercoideae are a major component of Asian monsoon forests, and are characterized by the possession of radial-porous wood. A characteristic of radial-porous wood is the development of aggregate rays between radially oriented files of vessels. We measured the distribution of vessel lumen diameters in a stem cross section and calculated the theoretical water conductivity of the wood. The radial profile of the heat pulse velocity (HPV) was measured for an intact whole tree under field conditions and compared with the theoretical distribution of water conductivity. Soft X-ray photographs of frozen stem sections indicated that most of the vessel lumina were filled with water, including those of vessels more than 20 years old. Even when vessels were relatively wide (lumen diameters > 100 microm), cavitation was negligible. The rate of water uptake from the cut stem base correlated closely with HPV (r = 0.96), and HPV closely reflected the mean volume flow per stem sectional area (SFVS) around the sensor probes. However, the ray tissue sharply inhibited heat transfer, and the positioning of the probes strongly affected the absolute value of HPV. It was also found that HPV more closely reflected the mean sap flow velocity in the vessels than did SFVS.  相似文献   
7.
Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed with-xylanase ofStreptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-x8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH2 column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 32--l-arabinofuranosyl-xylobiose, 32--l-arabinofuranosyl-xylotriose, 32--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylobiose, 33--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylotriose, 23--4-O-methyl-d-glucuronosyl-xylotriose, and 23--d-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of singlel-arabinose and singled-glucuronic acid but also stubs of disaccharide units such as-d-xylopyranosyl-(1 2)-l-arabinofuranose.  相似文献   
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The objective of this study was to examine the health and meat production of cloned sows and their progenies in order to demonstrate the application of somatic cell cloning to the pig industry. This study compared the growth, reproductive performance, carcass characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies. We measured their body weight, growth rate and feed conversion and performed a pathological analysis of their anatomy to detect abnormalities. Three of the five cloned pigs were used for a growth test. Cloned pigs grew normally and had characteristics similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a Landrace boar and used for a progeny test. F1 progenies had characteristics similar to those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White boar and used for the progeny test. F2 progenies grew normally. There were no biological differences in growth, carcass characteristics and amino acid composition among cloned sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies showed normal reproductive performance. No specific abnormalities were observed by pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs had a normal karyotype. These results demonstrate that cloned female pigs and their progenies have similar growth, reproductive performance and carcass quality characteristics and that somatic cell cloning could be a useful technique for conserving superior pig breeds in conventional meat production.  相似文献   
10.
GEN  KUME  ATSUKO  YAMAGUCHI  ICHIRO  AOKI 《Fisheries Science》2003,69(2):249-259
ABSTRACT:   Life history parameters (growth pattern, the length of the spawningseason and age at sexual maturity) of Apogon lineatus wereinvestigated from three localities in Japan. The maximum ages werefound to be 3 years in Tokyo Bay, 2 years in Osaka Bay and 5 yearsoff Niigata Prefecture. Both sexes from Tokyo Bay grew to largersizes between the ages of 1 and 2 years than both sexes from otherlocalities, food availability being suggested as the major factorfor differences in growth. Spawning seasons were during 4 months(July–October) in Tokyo Bay and Osaka Bay, but were foundto only occur during the two months of July and August off NiigataPrefecture. Factors that could limit the spawning season off NiigataPrefecture were not determined. Age at maturity for both sexes inall localities appeared to be 1 year. We could not elucidate whetherthese variations in life history parameters arose from genetic differencesor from phenotypic plasticity. In either case, the trade-off betweenthe maximum age and the length of the spawning season in the offNiigata Prefecture population and any other population may be interpretedas an adaptation to local conditions, such as with the off NiigataPrefecture population.  相似文献   
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