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101.
The waterchestnut ecosystem of Lake Kasumigaura is at the climax stage of eutrophication. Organic debris in the ecosystem showed highly dynamic fluctuations throughout the year. This was chiefly attributed to high viable fractions of organic matter in the hypereutrophic water. The stability of steady-state equilibrium of organic debris was found to be maintained even in such a dynamic ecosystem, likely due to the precedence of heterotrophic processes over autotrophic processes. Using a mathematical model approximated by in situ data, the turnover time of organic solutes was analyzed to be between four and six months through these active heterotrophic processes. 相似文献
102.
pp. 859–864
Behavior of nitrogen in the media was investigated when the aqueous phase produced by methane fermentation was supplied as liquid fertilizer.
When the aqueous phase was supplied to masa-soil, included in masa-soil was nitrified to . Additionally, in masa-soil, absorption was observed. On the other hand, in the case of coconut fiber and rockwool, has been hardly nitrified. From above results, it was determined that toxic effect from the aqueous phase on tomato plants growth was inhibited by means of the progress of nitrification and absorption by masa-soil.
However, nitrification was restrained so that was fixed in masa-soil. On the other hand, in the sampled field soil, was not fixed, and was nitrified immediately. In the field soil, there was a great deal of generated . In comparison with masa-soil. 相似文献
Behavior of nitrogen in the media was investigated when the aqueous phase produced by methane fermentation was supplied as liquid fertilizer.
When the aqueous phase was supplied to masa-soil, included in masa-soil was nitrified to . Additionally, in masa-soil, absorption was observed. On the other hand, in the case of coconut fiber and rockwool, has been hardly nitrified. From above results, it was determined that toxic effect from the aqueous phase on tomato plants growth was inhibited by means of the progress of nitrification and absorption by masa-soil.
However, nitrification was restrained so that was fixed in masa-soil. On the other hand, in the sampled field soil, was not fixed, and was nitrified immediately. In the field soil, there was a great deal of generated . In comparison with masa-soil. 相似文献
103.
Inhibitory effect of (-)-epigallocatechin 3-gallate, a polyphenol of green tea, on neutrophil chemotaxis in vitro and in vivo 总被引:1,自引:0,他引:1
Takano K Nakaima K Nitta M Shibata F Nakagawa H 《Journal of agricultural and food chemistry》2004,52(14):4571-4576
The effect of (-)-epigallocatechin 3-gallate (EGCG), a major polyphenol of green tea, on neutrophil migration has been studied using multiwell-type Boyden chambers in vitro and a fluorescein isothiocyanate-labeled ovalbumin (FITC-OVA)-induced rat allergic inflammation model in vivo. EGCG inhibited rat neutrophil chemotaxis toward cytokine-induced neutrophil chemoattractant-1 (CINC-1) in a concentration-dependent manner. In addition, CINC-1-induced neutrophil chemotaxis was suppressed by the pretreatment of rat neutrophils with EGCG at the concentration over 15 microg/mL. EGCG caused concentration-dependent suppression of the transient increase in CINC-1-induced intracellular free calcium level in both rat neutrophils and rat CXC chemokine receptor 2 (CXCR2)-transfected HEK 293 cells. EGCG inhibited CINC-1 production by IL-1beta-stimulated rat fibroblasts (NRK-49F cells) and lipopolysaccharide-stimulated rat macrophages at the concentration over 50 microg/mL, a comparatively high concentration. Oral administration of EGCG (1.0 mg or 1.5 mg/rat) at 1 h before the challenge with FITC-OVA suppressed neutrophil infiltration into the air pouch (inflammatory site) in the air-pouch type FITC-OVA-induced allergic inflammation in rats. Chemokine levels in the pouch fluids, however, were not influenced by EGCG administration. The results suggest that EGCG suppressed neutrophil infiltration by a direct action on neutrophils, but not by indirect actions, including the suppression of chemokine production at the inflammatory site. 相似文献
104.
We derive a two-way volume equation for estimating the apparent culm volume of one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. The volume equation was derived from the assumptions that (1) the relative culm form can be expressed by Kunze’s
equation and (2) normal form-factors at two different relative heights are steady at constants independent of culm sizes.
A total number of 200 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan, and were randomly bisected into two sets of data, i.e. modeling and test
data. For the modeling data, normal form-factors at 0.6 and 0.9 in relative height were steady at 0.908 and 0.448, respectively.
The coefficients of the volume equation were determined based on these steady values of the normal form-factors. For the test
data, the apparent culm volume was estimated from diameter at breast height and culm height with the determined volume equation.
The mean error and root mean square error of the estimated culm volume were, respectively, 8.120 × 10−5 and 3.291 × 10−3 m3, and there was no significant difference between estimated and actual volume. In conclusion, the two-way volume equation
presented here appears to be convenient for predicting the apparent culm volume for P. pubescens. 相似文献
105.
Takuya Shiraishi Hideo Hoshi Koki Eimori Takeshi Kawanishi Ken Komatsu Masayoshi Hashimoto Kensaku Maejima Yasuyuki Yamaji Shigetou Namba 《Journal of General Plant Pathology》2011,77(4):269-272
Helleborus net necrosis virus (HeNNV) in hellebores (Helleborus spp.) has been detected for the first time in Japan. Infected plants had black streaks on fresh leaves and black spots on
sepals, which resembled the symptoms of black death disease. The morphology of the virus particles isolated from infected
plants was comparable to that of carlaviruses. RT-PCR analysis showed that the entire HeNNV genomic sequence isolated in Japan
shared 99% identity with that of HeNNV previously reported in the United States. 相似文献
106.
Molecular mechanisms of metabolism and modes of actions of agrochemicals and related compounds are important for understanding selective toxicity, biodegradability, and monitoring of biological effects on nontarget organisms. It is well-known that in mammals, cytochrome P450 (P450 or CYP) monooxygenases metabolize lipophilic foreign compounds. These P450 species are inducible, and both CYP1A1 and CYP1A2 are induced by aryl hydrocarbon receptor (AhR) combined with a ligand. Gene engineering of P450 and NADPH cytochrome P450 oxidoreductase (P450 reductase) was established for bioconversion. Also, gene modification of AhRs was developed for recombinant AhR-mediated β-glucronidase (GUS) reporter assay of AhR ligands. Recombinant P450 genes were transformed into plants for phytoremediation, and recombinant AhR-mediated GUS reporter gene expression systems were each transformed into plants for phytomonitoring. Transgenic rice plants carrying CYP2B6 metabolized the herbicide metolachlor and remarkably reduced the residues in the plants and soils under paddy field conditions. Transgenic Arabidopsis plants carrying recombinant guinea pig (g) AhR-mediated GUS reporter genes detected PCB126 at the level of 10 ng/g soils in the presence of biosurfactants MEL-B. Both phytomonitoring and phytoremediation plants were each evaluated from the standpoint of practical uses. 相似文献
107.
Konishi K Yonai M Kaneyama K Ito S Matsuda H Yoshioka H Nagai T Imai K 《The Journal of reproduction and development》2011,57(5):572-578
The reproductive ability, milk-producing capacity, survival time and relationships of these parameters with telomere length were investigated in 4 groups of cows produced by somatic cell nuclear transfer (SCNT). Each group was produced using the same donor cells (6 Holstein (1H), 3 Holstein (2H), 4 Jersey (1J) and 5 Japanese Black (1B) cows). As controls, 47 Holstein cows produced by artificial insemination were used. The SCNT cows were artificially inseminated, and multiple deliveries were performed after successive rounds of breeding and conception. No correlation was observed between the telomere length and survival time in the SCNT cows. Causes of death of SCNT cows included accidents, accident-associated infections, inappropriate management, acute mastitis and hypocalcemia. The lifetime productivity of SCNT cows was superior to those of the controls and cell donor cows. All SCNT beef cows with a relatively light burden of lactation remained alive and showed significantly prolonged survival time compared with the cows in the SCNT dairy breeds. These results suggest that the lifetime productivity of SCNT cows was favorable, and their survival time was more strongly influenced by environmental burdens, such as pregnancy, delivery, lactation and feeding management, than by the telomere length. 相似文献
108.
Izawa T Murai F Akiyoshi H Ohashi F Yamate J Kuwamura M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(5):697-700
A 6-month-old male miniature pinscher dog developed chronic ascites, formation of fibrous membrane covering the abdominal organs, and numerous adhesions between the intestinal loops. The membrane and adhesions were surgically removed twice, but the dog died 1 month after initial presentation. Necropsy revealed recurrence of the membrane and intestinal adhesions. The fibrous membrane was composed of a thick layer of mature collagenous connective tissue, covered by immature collagenous connective tissue with mild lymphoplasmacytic infiltration, prominent neovascularization, and fibrin exudation. Similar fibrotic lesions were observed in the serosa of the liver, spleen, stomach and intestines. These findings are consistent with encapsulating peritoneal fibrosis reported in humans and dogs. The dog also had a maldeveloped liver, which is characterized by disorganized hepatic lobules and disarranged hepatic cords. 相似文献
109.
通过对人参近十年的产量、价格、出口量的研究,了解和把握人参产业的发展现状,并合理的对未来人参的发展趋势进行合理的推测。就整体而言,近十年的人参发展过程中,人参的出口市场总体处于一个相对稳定的发展阶段。未来对人参的需求将会逐年提高,怎样保证人参产量与质量已经成为新的课题。 相似文献
110.
Y Gotoh J Netsu M Nakai T Nasu 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(7):755-760
To study how long-term testicular damage depends on the patency of the efferent ductules (EFDs), rat testes and epididymides were examined after a single exposure to carbendazim (methyl 2-benzimidazole carbamate; MBC). The number of patent EFDs was determined in sections of the caput epididymides at 8, 16, 32 and 70 days post-treatment, and the testes were grouped into the following categories: those with intact EFDs, those with partially patent EFDs, or those with totally occluded EFDs. In each testis, 100 seminiferous tubules were examined for the presence of abnormalities. The mean weight of testes with partially patent EFDs was significantly higher compared with the control, whereas that of testes with totally occluded EFDs was significantly lower. Histologically, most seminiferous tubules of the testes with intact EFDs were normal. The testes with partially patent EFDs contained normal, degenerative and atrophic seminiferous tubules at various frequencies depending on the number of patent EFDs, and it was evident that as the number of patent EFDs increased, the number of normal seminiferous tubules also increased at any interval. In these testes, the number of normal seminiferous tubules increased progressively as the post-treatment interval increased, irrespective of patency of the EFDs. In the testes with totally occluded EFDs, atrophic seminiferous tubules were the most numerous. These results indicate that whether or not the testis is able to survive the long-term deleterious effects of MBC depends largely EFD patency. 相似文献