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101.
We performed a field experiment in thebiodegradation of heavy oil spilled from the Russian tankerNakhodka on a beach in the Sea of Japan. We collectedoil-contaminated cobbles and treated half with nitrogen andphosphorus slow-release fertilizers to stimulate microbialdegradation of the oil; the other half acted as unfertilizedcontrols. The cobbles were placed in porous acrylic vessels andsubmerged. We monitored changes in the oils, macronutrients,microbial community structure and amount of chlorophyll a. There were no significant differences in these criteriabetween the fertilized and unfertilized vessels, apart from anincrease in chlorophyll a in the fertilized vessels.However, there was a major intrinsic degradation of semi-volatile oil compounds in the unfertilized vessels; this occurred at a rate similar to that in the fertilized vessels, despite the low concentration of macronutrients in the seawater at the site.  相似文献   
102.
We evaluated the effects of feeding high volumes of milk replacer on growth and reproductive performances in Japanese black heifers. Fifty-one heifers were fed milk replacer at 9 L/day for 60 days (9 L × 60 days; n = 18) or 41 days (9 L × 41 days; n = 15), or at 7 L/day for 40 days (7 L × 40 days; n = 18). Artificial insemination (AI) was performed on heifers with ≥270 kg body weight and ≥116 cm body height at 300 days of age. The age at the first AI was 0.35 month later for 7 L × 40 days than the other groups (p < .01). However, age at calving did not differ among treatments (22.1 months). The interval from the first AI to pregnancy tended to be ~2 months longer for the 9 L × 60 days than the other groups (p = .07). Our results showed that feeding high volumes of milk replacer may reduce the age at calving via an improved rate of growth. In addition, we propose that feeding a maximum of 7 L milk replacer for 40 days may be the most appropriate rearing regime because the success of pregnancy per AI may be reduced in calves fed a maximum of 9 L for 41 and 60 days.  相似文献   
103.
Rheumatoid factor secretion from human Leu-1+ B cells   总被引:48,自引:0,他引:48  
A human B cell subpopulation identifiable by the expression of the cell surface antigen Leu-1 (CD5) is responsible for most of the immunoglobulin M rheumatoid factor secreted in vitro after the cells are stimulated with Staphylococcus aureus. The ability of B cells bearing the Leu-1 marker (Leu-1+) to secrete rheumatoid factor is present early in development and extends to adulthood, since Leu-1+ B cells from cord blood and from peripheral blood lymphocytes of both normal adults and patients with certain autoimmune conditions secrete rheumatoid factor in comparable amounts. The neonatal enrichment of Leu-1+ B cells, the presence of Leu-1+ B cells in increased frequencies in patients with autoimmune disease, and the involvement of Leu-1+ B cells in autoantibody secretion suggest both developmental and functional homologies between this human B cell subpopulation and the murine Ly-1 B cell subpopulation.  相似文献   
104.
Working with fused phosphate containing Mg, we have known some of the Mg-deficient areas in Shizuoka prefecture as a field problem. In these areas, crop plants develop visual hunger signs, resulting in restricted growth and reduced yield. The manurial effect of Mg-salt added or fused phosphate is remarkably excellent in these areas or soils.  相似文献   
105.
Four clonal lines of ayu, Plecoglossus altivelis, were produced from mitotic-gynogenetic diploids, mixed before hatching and reared communally. After 9 months, the clonal fish were sacrificed for measurement of body size, morphometric relationships, and meristic counts. DNA fingerprinting was used to confirm the clonal nature of the fish and to identify the clonal line of origin for each fish.

Significant differences were observed among clonal lines for almost all body size, morphometric and meristic measures. Such differences are suggested to represent genotypic difference among clonal lines given the common environmental conditions provided to all the experimental groups, assuming that the genotype-environment interaction was negligible.

By applying the human twin model, genetic and environmental variances in the clonal population was estimated after the clonal lines were separated by DNA fingerprinting. Heritability estimates for data collected at 9 months were relatively high for body size and varied from low to high in meristic and morphometric traits. These results suggest the possible usage of clonal lines as a control fish for estimation of heritability of traits important to aquaculture.  相似文献   

106.
A method for obtaining a relative deer population density index with low cost and effort is urgently needed in wildlife protection areas that need their own deer management guidelines. We recorded the number of deer sighted during our daily trips on forest roads by car in Ashiu Forest at Kyoto University, Japan, beginning in 2006. We used generalized additive mixed models (GAMMs) to estimate among-year trends in the number of deer sighted. We applied models for the total number of deer (TND), number of adults (NA), and number of fawns (NF) sighted, which included both current-year and 1-year-old fawns. Full models included the terms of year (2007, 2008, 2009, and 2010), weather (fine, cloudy, and rain/snow), and nonlinear effects of season (date) and time (time). The optimal GAMMs for TND, NA, and NF did not include the effect of weather but included those of time, date, and year. The detected among-year trends in deer population may be influenced by differences in snow environments among the years. The modeling of road count data using GAMM quantitatively determined among-year variation in the number of deer sighted. This trend was similar to that of the population density estimated using a block count survey conducted in Ashiu Forest.  相似文献   
107.
108.
The fully ripened fruit of Katsura-uri Japanese pickling melon ( Cucumis melo var. conomon) has rarely been used for food because the midripened fruit is utilized for making pickles, but the fully ripened fruit is no longer valuable for pickles due to the fruit body being too soft. We have considered the utilization of the fully ripened Katsura-uri fruit that may be used for nonpickling products, particularly if the fully ripened fruit demonstrated health benefits such as anticarcinogenic properties. The phytochemical extract from the fully ripened fruit of Katsura-uri Japanese pickling melon was purified via a bioassay-guided fractionation scheme, which was based on the induction of differentiation in a RCM-1 human colon cancer cell line. On the criteria of two differentiation markers (duct formation and alkaline phosphatase activity), the most potent fraction contained a compound identified as 3-methylthiopropionic acid ethyl ester, based on GC retention time, EI-MS, (1)H NMR, and (13)C NMR spectra. Previously, the role of 3-methylthiopropionic acid ethyl ester was considered as an odor producing compound in many fruits, but this study indicates potential medical benefits of this compound.  相似文献   
109.
In ultrasonographic diagnosis of ovarian disorders and the estrous cycle in sows, transverse observation of the uterus yielded more characteristic findings than observation of sagittal sections. Transverse ultrasonography revealed that the low progesterone (P) type uterus showed a round structure, while the high P type uterus showed a flattened structure. These results corresponded well with rectal palpation findings: the low P type uterus had a hard, pipe-like structure and the high P type a soft, balloon-like structure. For gilts, we employed a minimum convex type transrectal prostate probe that had an approximately 18 cm insertion handle. The images of the uterus obtained thereby were a similar to those obtained from sows. The above results suggest that it should be possible to diagnose and treat many ovarian disorders in sows and gilts based only on the ultrasonograhic findings. In short, ultrasonograhic findings of a round structure of the uterine wall might be an indication for PMSG (pregnant mare serum gonadotropin) treatment, while findings of a flattened structure might be an indication for PGF(2) (alpha) administration.  相似文献   
110.
Erythrocyte 5'-nucleotidase is thought to be involved in the maturation of erythrocytes. In the present study, in vitro incubation of canine erythrocytes demonstrated that significant inhibition of 5'-nucleotidase activity occurred in the presence of serum from dogs infected with Babesia gibsoni, when the enzyme was assayed with cytidine 5'-monophosphate (5'-CMP) and inosine 5'-monophosphate (5'-IMP) as substrates. The multiplication of B. gibsoni in in vitro culture also resulted in a significant decrease in the enzyme activity of erythrocytes in the culture. Furthermore, the infected serum and 5'-CMP retarded the maturation of canine reticulocytes in vitro. These results suggested that nucleotides such as 5'-CMP and 5'-IMP might accumulate in young erythrocytes and/or serum in dogs infected with B. gibsoni as a result of decreased activity of erythrocyte 5'-nucleotidase, resulting in the delayed maturation of reticulocytes.  相似文献   
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