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1.
ABSTRACT:   The ability of salmon growth hormone (sGH) to accelerate the somatic growth of juvenile abalone Haliotis discus hannai by immersion was examined. After immersion for one hour into a sGH-rich solution at a concentration of 30 mg/L, the sGH immunoreactivity in the body fluid of abalone was maximal after one day, and levels were still detectable at two days. No immunoreactivity was observed in the control group. Following immersion for one hour at one or two-week intervals for 120 weeks into the sGH-rich solution at 30 mg/L, the sGH-immersed abalone exhibited a significant increase in shell length and body weight. On the other hand, abalone immersed into a salmon prolactin (sPRL)-rich solution at 30 mg/L for one hour showed a lower increase in both shell length and body weight than the sGH-immersed abalone. No increases in shell length and body weight were observed in either the bovine serum albumin-immersed abalone or untreated controls. These results provide evidence that sGH can be transported from ambient water into the circulatory system of abalone, and can subsequently improve the somatic growth of juveniles.  相似文献   
2.
In a previous study, we developed male sterile lines of Japanese bunching onion (Allium fistulosum L.) possessing the cytoplasm of a wild species, A. galanthum Kar. et Kir., by backcrossing. To evaluate seed productivity of the male sterile lines in practise, they were crossed with the male fertile line, cultivar 'Kujyo', using honeybees as pollinators under field conditions. The number of florets and seeds per inflorescence, seed set and seed germination of the material were investigated. Although variation was observed among the male sterile lines, there were several lines having seed productivity equal to cultivar 'Kujyo'. Our data demonstrate that the male sterile lines of A. fistulosum possessing the cytoplasm of A. galanthum are useful as seed parents for the commercial F seed production of A. fistulosum.  相似文献   
3.
In early February 1990, vandals set fire to a used tire storage facility near Hagersville, Ontario, Canada, During the fire, the Ontario Ministry of Environment and Energy (MOEE) monitored the site and surrounding impact zone for numerous organic contaminants. Samples of air, soil, vegetation, runoff water, and oily residue were collected and analyzed for polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF). Air samples produced complex incineration patterns with a large number of isomers detected. Total toxicity equivalents (TEQ) at 1 km downwind of the fire were an order of magnitude higher than those at 3 km downwind. Soil samples collected during the fire did not show elevated PCDD or PCDF concentrations, however, low concentrations were detected in vegetation collected at 100 m and 200 m from the site. PCDD and PCDF concentrations in the foliage decreased with time but were still detectable for at least 200 days after the fire started. As the tires burned, water used to extinguish the fire caused runoff of oil and oily water. Unique patterns of PCDDs and PCDFs were detected in these samples.  相似文献   
4.
Antigenic and genetic analysis of the hemagglutinin of approximately 13,000 human influenza A (H3N2) viruses from six continents during 2002-2007 revealed that there was continuous circulation in east and Southeast Asia (E-SE Asia) via a region-wide network of temporally overlapping epidemics and that epidemics in the temperate regions were seeded from this network each year. Seed strains generally first reached Oceania, North America, and Europe, and later South America. This evidence suggests that once A (H3N2) viruses leave E-SE Asia, they are unlikely to contribute to long-term viral evolution. If the trends observed during this period are an accurate representation of overall patterns of spread, then the antigenic characteristics of A (H3N2) viruses outside E-SE Asia may be forecast each year based on surveillance within E-SE Asia, with consequent improvements to vaccine strain selection.  相似文献   
5.
To assess whether the antigenic properties of H5 hemagglutinin (HA) change over time due to antigenic drift, we produced a panel of monoclonal antibodies (mAbs) against the HA of the index H5N1 human influenza A virus, A/Hong Kong/156/97. By immunizing mice with a plasmid expressing this HA and boosting the initial immunization with cell lysates transfected with the plasmid, a total of six hybridomas producing HA-specific mAbs were established: four to the HA1 subunit with hemadsorption-inhibiting activity and two to the HA2 subunit. None of the mAbs to HA1 could bind to the HA of a recent human isolate, A/Hong Kong/213/2003, indicating that there are substantial antigenic differences between the H5N1 human influenza virus isolated in 1997 and that isolated in 2003.  相似文献   
6.
PCR-RFLP analyses of three regions for each of chloroplast DNA (cpDNA; rbcL-ORF106, trnD-trnT, trnH-trnK) and mitochondrial DNA (mtDNA; nad7/exon2-exon3, nad7/exon3-exon4, 18S-5S) were performed in 26 cultivars of acid citrus grown in Japan to identify polymorphisms and classify them. The polymorphisms were compared with those of three true Citrus species, i.e., mandarin, pummelo and citron. Ichang papeda (C. ichangensis) was also included in this study to find its relationship with Yuzu. Inter-species cpDNA variation was recognized and the acid citrus were divided into three groups, namely; I (‘Yuzukichi’ and ‘Kinkoyu’), II [sour oranges (‘Kaiseito’, ‘Daidai’ and ‘China daidai’), ‘Nansho daidai’, ‘Kiku daidai’, C. sudachi (‘Mushi yukaku’, ‘Yushi yukaku’ and ‘Yushi mukaku’), C. sphaerocarpa (‘Kabosu’ and ‘Aka kabosu’), C. kizu (‘Taninaka kizu’, ‘Kinosu’ and ‘Kizu’), ‘Zanbo’, ‘Mochiyu’, ‘Jabara’ and ‘Naoshichi’], and III [Yuzu (‘Tetraploid’, ‘Tochikei yuzu’ and ‘Yamanekei yuzu’), ‘Matsuda sudachi’, ‘Zuishoyu’, ‘Hanayu’ and ‘Yuko’]. CpDNA restriction patterns of the three true Citrus species differed from each other as well as from those of ichang papeda. CpDNA restriction patterns of group I of the acid citrus were identical to those of mandarins. Group II showed the same as pummelos. CpDNA restriction patterns of group III were differed from those of the three true Citrus species in the three regions. This group was differed from ichang papeda after digestion of trnH-trnK PCR products with TaqI, HinfI and AluI, while they showed identical restriction patterns in two regions, rbcL-ORF106 and trnD-trnT. Citrons and ichang papeda were placed in groups IV and V, respectively. Based on mtDNA restriction patterns, the acid citrus were divided into three groups; i, ii and iii. In groups i and ii accessions of groups I and II of cpDNA were placed with mandarins and pummelos, respectively. In group iii accessions of group III of cpDNA were placed with ichang papeda. Citrons were placed in a distinct group, iv.  相似文献   
7.
RFLP analysis of a PCR amplified 3.2-kbp region of cpDNA bounded by the conserved sequences in rbc L and ORF 106 was performed in eggplant (Solanum melongena), its related Solanum species, S. incanum, S. virginianum (= S. surattense), S. torvum, S. aethiopicum (= S. gilo), S. aethiopicum (= S. integrifolium), S. violaceum (= S. indicum), S. violaceum (= S. sanitwongsei) and S. mammosum and the reciprocal hybrids between S. aethiopicum (= S. integrifolium) and S. melongena 'Uttara'. The target region of cpDNA was amplified correctly by PCR. The amplified products were digested with each of 10 restriction enzymes (Alu I, Ase I, BamH I, Hinf I, Msp I, Rsa I, ScrF I, Sty I, Taq I and Xba I). Variations of restriction patterns among the species were recognized after digesting the amplified products with each of the seven restriction enzymes, Taq I, Alu I, Rsa I, Sty I, Ase I, Hinf I and Xba I. The restriction patterns divided the examined nine species into the following five clusters, 1) S. melongena and S. incanum, 2) S. virginianum (= S. surattense), 3) S. torvum, 4) S. aethiopicum (= S. gilo), S. aethiopicum (= S. integrifolium), S. violaceum (= S. indicum) and S. violaceum (= S. sanitwongsei) and 5) S. mammosum. The restriction pattern with Alu I in each of the reciprocal hybrids between S. melongena 'Uttara' and S. aethiopicum (= S. integrifolium) was identical with that of seed parent. The present study demonstrated the availability of the PCR-RFLP analysis of cpDNA for assessing taxonomic relationships and identifying cytoplasmic parentage of interspecific hybrids in eggplant and related Solanum species. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
8.
The molecular structure and some physicochemical properties of starches from two high‐amylose cultivars of barley, high‐amylose Glacier A (HAG‐A) and N (HAG‐N), were examined and compared with those of a normal cultivar, Normal Glacier (NG). The true amylose contents of HAG‐A, HAG‐N, and NG were 41.0, 33.4, and 23.0%, respectively. Iodine affinities before and after defatting of starch, and thermograms of differential scanning calorimetry, indicated that HAG‐A and HAG‐N starches had a higher proportion of amylose‐lipid complex than did NG starch. The amylopectins from HAG‐A and HAG‐N were similar to NG amylopectin in average chain length (18–19), β‐amylolysis limit (β‐AL 56–57%), number‐average degrees of polymerization (DPn 6,000–7,500) and chain length distribution. Very long chains (1–2%) were found in amylopectins from all cultivars. HAG‐A amylopectin had a larger amount of phosphorus (214 ppm) than the others. The amyloses from HAG‐A and HAG‐N resembled NG amylose in DPn (950–1,080) and β‐AL (70–74%). However, HAG‐A and HAG‐N had a larger number of chains per molecule (NC 2.4–2.7) than NG amylose (1.8) and contained the branched amylose with a higher NC (9.5–10.6) than that of NG amylose (5.8), although molar fractions of the branched amylose (15–20%) were similar.  相似文献   
9.
Effects of sika deer (Cervus nippon) and dwarf bamboo (“sasa;” Sasamorpha borealis) on seedling emergence and survival were investigated in cool-temperate mixed forests in the Kyushu mountain range, Japan. We compared the effects of sika deer between two sites with different sika deer densities. One site (no-sasa forest) has sparse cover of S. borealis and a high density of sika deer, and the other site (sasa forest) has dense cover of S. borealis with a low density of sika deer. In the no-sasa forest, more seedlings emerged and the survival rate of the seedlings was higher compared with the sasa forest. Compared with the sasa forest, the canopy in the no-sasa forest was more open, the organic layer was shallower and drier, the mean daily soil temperature was higher, and soil temperature fluctuated more widely. Those environmental parameters did not differ between unfenced and fenced plots. The comparison between the sasa and no-sasa forests suggested that removal of S. borealis by sika deer had an indirect positive effect on seedling emergence and survival. However, the fenced-plot experiments indicated that sika deer inhibited seedling emergence and survival. These contradictory conclusions could result from the much larger negative effects of S. borealis on seedling emergence and survival compared with the effects of sika deer browsing.  相似文献   
10.
Streptomyces scabies, causative agent of common scab of potato, produces the phytotoxins concanamycin and thaxtomin. In a potato tuber slice assay to study the contribution of concanamycins to lesion development, concanamycin A had weak necrosis-inducing activities; >10× the amount of thaxtomin A was needed to produce equivalent lesion severity. Concanamycins were detected in tubers inoculated with S. scabies, which caused deep-pitted lesions but not in those inoculated with Streptomyces acidiscabies, which caused corky, raised lesions. In field-grown, diseased potatoes, concanamycin content tended to be higher in tubers with deep-pitted lesions than in those with corky, raised lesions.  相似文献   
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