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The objective of this study was to obtain fundamental data for improving the color of meat products by using animal by‐products. We investigated zinc protoporphyrin IX (ZnPP)‐forming properties of various internal organs from pigs and chickens. ZnPP was formed in the liver, heart and kidney, whereas the porcine spleen and bile, which are involved in the metabolism of heme, did not have ZnPP‐forming properties. The optimum pH values were different among the internal organs and the ZnPP‐forming properties of porcine organs were better than those of chicken organs. The porcine liver showed the greatest ZnPP‐forming properties among all of the internal organs investigated in this study. The optimum pH value for ZnPP formation in the liver was lower than that of skeletal muscle. Oxygen did not inhibit the formation of ZnPP in the liver, unlike in skeletal muscle. Animal by‐products such as the liver have good ability for the formation of ZnPP and might be useful for improving the color of meat products.  相似文献   
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Neurologic diseases are common in domestic cats, and infectious agents are suspected to be the primary cause in 30–45% of cases. Among infectious etiologies, those of bacterial origin are only sporadically characterized in the literature, with few of these reports correlating gross and histologic findings with confirmatory bacteriologic identification. Here, we describe bacterial meningitis and meningoencephalomyelitis associated with Pasteurella multocida in 3 domestic cats. Purulent exudate expanding the cerebral meninges was grossly evident in 2 of the cases. In all 3 cases, histologic changes included multifocal suppurative-to-necrosuppurative meningitis and/or meningoencephalomyelitis of variable severity. Intralesional colonies of gram-negative, short rod-shaped to coccobacillary bacteria were evident histologically in only 1 case. P. multocida was confirmed by routine bacteriologic culture in all cases. Based on our cases, we hypothesize that the upper respiratory system serves as the main portal of entry for P. multocida, leading to invasion of the central nervous system and possible systemic hematogenous dissemination. A case series of meningoencephalomyelitis associated with P. multocida infection in cats has not been reported previously, to our knowledge. We also review briefly other causes of meningoencephalomyelitis in cats.  相似文献   
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The Dahurian larch forest in northeast China is important due to its vastness and location within a transitional zone from boreal to temperate and at the southern distribution edge of the vast Siberian larch forest. The continuous carbon fluxes were measured from May 2004 to April 2005 in the Dahurian larch forest in Northeast China using an eddy covariance method. The results showed that the ecosystem released carbon in the dormant season from mid-October 2004 to April 2005, while it assimilated CO2 from the atmosphere in the growing season from May to September 2004. The net carbon sequestration reached its peak of 112 g.m^-2.month ^-1 in June 2004 (simplified expression of g (carbon).m^-2.month^-1) and then gradually decreased. Annually, the larch forest was a carbon sink that sequestered carbon of 146 g-m^-2.a^-1 (simplified expression of g (carbon).m^-2.a^-1) during the measurements. The photosynthetic process of the larch forest ecosystem was largely affected by the vapor pressure deficit (VPD) and temperature. Under humid conditions (VPD 〈 1.0 kPa), the gross ecosystem production (GEP) increased with increasing temperature. But the net ecosystem production (NEP) showed almost no change with increasing temperature because the increment of GEP was counterbalanced by that of the ecosystem respiration. Under a dry environment (VPD 〉 1.0 kPa), the GEP decreased with the increasing VPD at a rate of 3.0 μmol.m^-2.s^-1kPa -1 and the ecosystem respiration was also enhanced simultaneously due to the increase of air temperature, which was linearly correlated with the VPD. As a result, the net ecosystem carbon sequestration rapidly decreased with the increasing VPD at a rate of 5.2 μmol.m^-2.s-1.kPa^-1. Under humid conditions (VPD 〈 1.0 kPa), both the GEP and NEP were obviously restricted by the low air temperature but were insensitive to the high temperature because the observed high temperature value comes within the category of the optimum range.  相似文献   
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Measurements of the chemical composition of fog water at Murododaira (altitude, 2,450 m), on the western slope of Mt. Tateyama near the coast of the Japan Sea, were performed each autumn from 2004 through 2007. Strong acidic fogs (pH?<?4) containing high concentrations of nssSO 4 2? were frequently observed in the autumn of 2005, when the air mass at Mt. Tateyama originated mainly from the polluted regions of Asia. The ratio of NO 3 ? /nssSO 4 2? in fog water was relatively high in 2004 and 2007. High concentrations of nssCa2+ derived from dust particles were detected in 2006. Background Kosa particles might have been predominant in the free troposphere and could have neutralized acidic fogs in the autumn of 2006. High concentrations of sea-salt components were also observed in October 2005. The sea-salt particles might have been transported from the Pacific Ocean by a strong typhoon, and significant Mg2+ loss was observed. Peroxides higher than 100 μM, which are seriously harmful to vegetation were sometimes detected.  相似文献   
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The proton budget for a Japanese cedar (Cryptomeria japonica) forest in Gunma Prefecture, Japan, was studied by estimating biogeochemical fluxes. The proton budgets were estimated for three individual compartments of the ecosystem: vegetation canopy, and the upper (O horizon + 0–10 cm) and lower (10–100 cm) soil layers. The dominant proton sources in the compartments were atmospheric deposition (1.2 kmol ha?1 yr?1), nitrification (5.1 kmol, ha?1 yr?1) and base-cation uptake by vegetation (8.0 kmol, ha?1 yr?1) respectively. These proton sources were neutralized almost completely within the individual compartments mainly by base-cation release from the canopy or the soil. The sum of internal proton sources was five times as large as that of external ones. Nitrogen input from the atmosphere was 2.2 kmol ha?1 yr?1, whereas its output from the lower soil layer was 3.9 kmol ha?1 yr?1, indicating that a net loss of nitrogen occurred in the ecosystem. However, this did not cause the acidification of soil leachates because of a sufficient release rate of base cations from the soil.  相似文献   
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T. Yamada  H. Fukuoka  T. Wakamatsu 《Euphytica》1989,44(1-2):167-172
Summary When white clover plants were self-pollinated, 75% of a 143-plant population did not set seed. Plants which did set small numbers of seed probably did so as a result of pseudo-self-compatibility. One highly self-compatible plant was selected from the breeding materials. The S2 progeny of this plant was autogamous and genetically fixed for morphology and isozyme patterns. Genetic analyses of self-compatibility were conducted as far as the F3 progeny. It was concluded from these data that self-compatibility was inherited in a simple Mendelian way and that plants homozygous for self-compatibility were obtained. There was no correlation between presence or absence of self-compatibility and growth vigor. The possibility of application of self-compatible plants to recurrent selection procedures is outlined and the utilization of self-compatible plants in white clover breeding programs is discussed.  相似文献   
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