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101.
Although water hyacinth is an adventive aquatic plant that threatens the Japanese ecosystem, its high growth rate may be a benefit in terms of its potential as a raw material for the production of bioethanol. In our study, water hyacinth was saccharified with 3?% (v/v) sulfuric acid and subjected to cellulase treatments to determine optimum bioethanol production conditions. The original saccharified solution yielded both glucose at 5.3?±?0.2?g/l and reducing sugars at 9.7?±?0.1?g/l. Concentration of the saccharified solution under vacuum at 70?°C yielded both glucose at 21.5?±?2.9?g/l and reducing sugars at 33.3?±?2.1?g/l. An aquatic yeast Saccharomyces cerevisiae TY2 produced ethanol at 9.6?±?1.1?g/l from the concentrated saccharified solution. In comparison, Ogawa et al. (Afr J Microbiol Res 2:110?C113, 2008) reported that this yeast produced 0.90?g/l and that the production of bioethanol was about 11.2-fold lower than that obtained in our study. These results suggest that refinement of the saccharification process and application of the selected yeast could improve the efficiency of obtaining bioethanol from the water hyacinth.  相似文献   
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103.
In order to contribute to conservation of the endangered Kiso horse, we clarified their genetic information using 31 microsatellite DNAs, and genotyped 125 horses, 83% of the existing breed. First, we clarified the current status of the horses. The horses were confirmed to have experienced rapid loss of population causing a bottleneck, and their effective population size was much smaller than their census size. Moreover, the number of alleles (6.3), observed heterozygosity (0.674), and expected heterozygosity (0.662) were in the same range as other endangered horses all over the world. Therefore, although their inbreeding level was not so severe (F(is): -0.017), the Kiso horse is surely one of the endangered. Second, we obtained genetic information of individuals. This information allowed us to understand the genetic distance of individuals, and might help in development of a reproductive strategy concerning the genetic distance between the mating pairs. Moreover, there appeared to be 4 subpopulations of Kiso horse, and this result was in good agreement with their historical background. Third, we confirmed that the parentage test for identification using the 31 microsatellite DNAs was highly reliable (probability of exclusion: 0.999999993). This identification increases the reliability of stud certification, and is also helpful for effective management. Understanding the genetic diversity within the population and the relationships among individuals is important to ensuring effective management for maintenance of genetic variation, and this study may help in conservation of the endangered Kiso horse.  相似文献   
104.
本研究以已建立的栽培方法、收割时期预测甘蔗单产和含糖量的数学模型为基础,提出将寻求最佳收割顺序、收割期归结为最优化组合问题,并探讨了遗传算法(GA)的解题适用性,同时进行了几种基本设定的栽培方法推移、栽培方法构成项量、行列式特性的定性分析,为求最佳的甘蔗收割顺序、收割期、不同栽培方法的面积等提供解析方法.为不使栽培方法的构成比例发生变化,与通常GA算法采用交叉在不同个体问互相交替进行不同,开发了适用本研究的GA的自己交叉具体解析法.将收割第1年期作为过渡状态,第2年期为安定状态,将两期目的函数的合并作为一个适应度进行评价.  相似文献   
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106.
The feline cardiac and serum angiotensin converting enzyme (ACE) and chymase activities were determined and compared in dogs, and hamsters. In all three species, cardiac chymase activity exceeded ACE activity; however, there were some differences. In cats, left ventricular ACE and chymase activities (0.15 +/- 0.01 and 0.59 +/- 0.1 mU/mg-protein, respectively) were lower than in dogs (0.42 +/- 0.05: p<0.01 and 2.0 +/- 0.4 mU/mg-protein: p<0.01) and hamsters (0.93 +/- 0.06: p<0.001 and 2.1 +/- 0.2 mU/mg-protein: p<0.01); in contrast, serum ACE activities was higher in cats (12.7 +/- 1.0 mU/ml) than in dogs (5.9 +/- 0.6 mU/ml: p<0.001). The relative contribution of chymase (cats: 84.0 +/- 5.1%, dogs: 81.4 +/- 3.4%, and hamsters: 72.6 +/- 5.6 %) to ANG-II formation in the heart was greater than that of ACE in these animals (cats: 10.9 +/- 4.1%, dogs: 11.5 +/- 3.6%, and hamsters: 17.2 +/- 0.8%). These species-specific differences suggest that the efficacy of renin-angiotensin system modulating agents may differ among species.  相似文献   
107.
To determine the acute effects of carvedilol (beta-blocker) on cardiovascular and renal function and its pharmacokinetics in dogs. Fifteen mature mongrel dogs (7-15 kg) of both sexes were used in these experiments. Eight dogs served as controls, and seven dogs served as iatrogenic mitral regurgitation (MR) experimental animals. Carvedilol (0.2, 0.4, and 0.8 mg/kg, P.O.) was administered, and the blood carvedilol concentration was analyzed by reverse-phase high-performance liquid chromatography. The response to isoproterenol or phenylephrine was also evaluated. Isoproterenol (0.025 microg/kg/min) was infused via the saphenous vein for 5 min, and phenylephrine (5 microg/kg) was injected with carvedilol (0.2, 0.4 mg/kg) or placebo for 4 days. The heart rate and arterial blood pressure were measured, and LV fractional shortening was measured by echocardiography. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured by intravenous infusion of sodium thiosulfate and sodium para-aminohippurate. Carvedilol (0.2 mg/kg) decreased the heart rate, whereas renal function, arterial blood pressure, and left ventricular contractile function were not affected. Carvedilol (0.4 mg/kg) decreased heart rate, blood pressure, and renal function. The tachycardic response to isoproterenol was significantly diminished for 36 hr by 0.4 mg/kg carvedilol. Carvedilol 0.2 mg/kg inhibited this effect for 24 hr. Thus, it is necessary to titrate the dosage of carvedilol, it should be initiated at less than 0.2 mg/kg and titrated up to 0.4 mg/kg for heart failure dogs.  相似文献   
108.
Fecal estradiol concentrations were measured in three captive unmated female sun bears (Helarctos malayanus) from August 1998 to July 1999 in Sarawak, Malaysia and vaginal smears from one of the females was observed in August 1998 and March 1999. A single peak in fecal estradiol concentration was obvious for each bear in August or September 1998, and there was a much higher percentage of superficial vaginal anuclear cells in August 1998 than in March 1999. These results suggest that sun bears in Sarawak are likely to be a seasonal breeder associated with a peak of estrogen production in August or September.  相似文献   
109.
Various dog breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of these characteristics are under genetic control. However, little is known about genes related to behavioral traits in canine species. In humans, it has been reported that the dopamine receptor D4 gene (DRD4) includes polymorphism at several regions that relate to personality or psychiatric disorders. In an earlier study by the authors of the present study, the polymorphisms in canine DRD4 exon III and exon I regions were reported. In the present study, a novel polymorphism in canine DRD4 intron II was found based on a 17 base pair insertion/deletion, and the two alleles detected were named P (shorter allele) and Q (longer allele). The allelic distribution in 28 breeds of dog, including a total of 1114 unrelated individuals, were then investigated. Both P and Q alleles were detected in most of the breeds investigated; however, the frequencies of P and Q differed greatly between breeds. With respect to classification based on breed origin, P and Q alleles were frequent in Occidental and Oriental breeds, respectively. Furthermore, two subspecies of wolves, the ancestors of dogs, were analyzed for the comparison of allele frequencies with dogs, and the P allele was predominant in both European and Chinese wolves.  相似文献   
110.
Rooting of shoots derived from axillary buds was examined to establish an efficient shoot culture system of clonal micropropagation in adult tree ofLarix leptolepis Gord. (Japanese larch). Nine out of ten shoots induced calli (90%) on their shoot bases, and the two of them formed root primordia with a red pigment (20%) on the calli surface within 5 weeks after culturing on modified Murashige and Skoog (MS) medium supplemented with 1.5 μM of indolebutyric acid (IBA) and 1.5 μM of naphthaleneacetic acid (NAA). However, the primordia did not elongate actively. The addition of 10 mMl-phenylalanine in the MS medium with the auxins resulted in the formation of roots at high frequency, about 80%, and they elongated actively. Although callus was formed in all the shoots cultured on the medium withl-phenylalanine, it appeared that the callus development was less as compared to the medium withoutl-phenylalanine. Consequently, the rooting might be associated with the suppression of the induced callus.  相似文献   
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