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41.
The effect of the endocrine-disrupting chemical 3,3',4,4',5-pentachlorobiphyenl (PCB 126) on intestinal microbiota after oral administration, and the improvement of intestinal microbiota and feces quantity by the subsequent administration of Lactobacillus acidophilus or Lactobacillus reuteri was investigated. All the rats were given 100 μg/kg bodyweight of PCB 126. The changes in bacterial counts were confirmed using a culture method. The administration of PCB 126 tended to decrease the bacterial counts of lactobacilli (109.6−1010.2 to 108.8−109.2) and bifidobacteria (105.3−106.1 to 103.6−104.2), and to increase those of Enterobacteriaceae (108.2−109.1 to 109.4−1010.3) and staphylococci (106.6−107.4 to 107.2−108.4) compared to no PCB 126 administration. After administration of PCB 126, L. acidophilus or L. reuteri orally administered to rats caused Enterobacteriaceae and staphylococci counts to decrease, suggesting that the intestinal microbiota was improved by the lactobacilli. The administration of L. acidophilus and L. reuteri improved the balance of intestinal microbiota, and defecation volume returned to its normal level. L. acidophilus and L. reuteri have a remedial effect on intestinal microbiota affected by PCB 126 and can function to lessen accumulated PCB 126 volume.  相似文献   
42.
Recently, we established the GEEP (“gene editing by electroporation of Cas9 protein”) method, in which the CRISPR/Cas9 system, consisting of a Cas9 protein and single guide RNA (sgRNA), is introduced into pig zygotes by electroporation and thus induces highly efficient targeted gene disruption. In this study, we examined the effects of sgRNA on the blastocyst formation of porcine embryos and evaluated their genome‐editing efficiency. To produce an animal model for diabetes, we targeted PDX‐1 (pancreas duodenum homeobox 1), a gene that is crucial for pancreas development during the fetal period and whose monoallelic disruption impairs insulin secretion. First, Cas9 protein with different sgRNAs that targeted distinct sites in the PDX‐1 exon 1 was introduced into in vitro‐fertilized zygotes by the GEEP method. Of the six sgRNAs tested, three sgRNAs (sgRNA1, 2, and 3) successfully modified PDX‐1 gene. The blastocyst formation rate of zygotes edited with sgRNA3 was significantly (< 0.05) lower than that of control zygotes without the electroporation treatment. Our study indicates that the GEEP method can be successfully used to generate PDX‐1 mutant blastocysts, but the development and the efficiency of editing the genome of zygotes may be affected by the sgRNA used for CRISPR/Cas9 system.  相似文献   
43.
The objectives of this study were to estimate and evaluate potassium (K) and magnesium (Mg) budgets and flows of animal production in the basin of Dianchi Lake, China. Feed sampling and farmer interviews were conducted in field surveys. The supplies of K and Mg from local and external feeds and the retention, production and excretion of animals were calculated individually for dairy cows, fattening pigs, breeding sows, and broilers and laying hens. The K and Mg flows on a regional level were estimated using the individual budgets. At the individual level, in dairy cattle, the K and Mg supplied from local feeds accounted for large parts of the total nutrient intakes, whereas in the other animal categories most of the K and Mg in the feeds depended on external resources. Our findings also suggested that excessive Mg intake resulted in high Mg excretion and low use efficiency in dairy cattle and fattening pigs. At the regional level, the K and Mg amounts of manure produced and applied in the area (K: 339 and Mg: 143 t/year) exceeded those used as local feeds. Our results imply the animal production potentially increased the K and Mg loads in the regional agriculture system.  相似文献   
44.
45.
Conclusions When the hydroxyl values of materials containing phenolic 3 or sterically hindered hydroxyl groups were determined by the esterification method, the values were considerably smaller than the theoretical values. In contrast, the NCO method provided hydroxyl values much closer to the theoretical values for such materials, though the values varied depending on the kinds and amounts of catalysts.The quantity of hydroxyl groups reacting with the NCO group could be directly determined by the NCO method using a catalyst mixture consisting of DABCO and DBTDL in a molar ratio of 21. Therefore, this method can be considered useful for determining the hydroxyl value before preparing polyurethane from liquefied wood or bark.Part of this paper was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 1988  相似文献   
46.
Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs.  相似文献   
47.
The anthocyanin profiles and variety/breeding-line differences of anthocyanin concentrations in petals of common buckwheat flowers have been studied. Four anthocyanins, cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, cyanidin 3-O-rhamnoside, and cyanidin 3-O-galactosyl-rhamnoside were isolated from the petals of common buckwheat (Fagopyrum esculentum Moench), separated using high performance liquid chromatography and identified using reversed-phase liquid chromatography-electrospray ionization-tandem mass spectrometry techniques. In every variety/breeding line tested, cyanidin 3-O-rutinoside was detected as the major anthocyanin and the next is cyanidin 3-O-glucoside whereas cyanidin 3-O-rhamnoside and cyanidin 3-O-galactosyl-rhamnoside were trace or not detectable in white and pink flowered buckwheat. Of all the varieties/breeding lines tested, Gan-Chao, a Chinese variety, contained the highest amount of anthocyanins. The largest part of cyanidin moiety was presented as a proanthocyanidin form (PAs-Cy). Anthocyanins and PAs-Cy in petals were increased along with increase of flower development stages. Therefore, fully developed petals of red flowered buckwheat, especially Gan-Chao, are promising as a new anthocyanin-rich material for food processing.  相似文献   
48.
The addition of Orvus ES paste (OEP) to extender may be essential for preparing frozen dog semen. The major ingredient of OEP is sodium lauryl sulfate (SLS). In this study, we compared the effect of SLS on frozen dog semen with that of OEP. There were no significant differences between the 2-mg/ml SLS group and OEP group concerning sperm motility, viability and the percentage of viable sperm with intact acrosomes after freeze-thawing. These results suggest that the effectiveness of frozen dog semen extender containing 2 mg/ml of SLS is similar effective to that demonstrated for OEP.  相似文献   
49.
The freezing conditions for preparation of frozen canine semen by the plunging method were investigated with regard to the period of sensitization in liquid nitrogen (LN2) vapor and the height from LN2, and the semen qualities after thawing were compared with those of canine semen prepared by the simple freezer method previously reported by us. In the plunging method, 9 semen straws were prepared under the same conditions, horizontally kept at 5, 7, and 10 cm above the LN2 surface in a styrene foam box for 5, 10, and 15 min, and then plunged into LN2. The semen qualities immediately after thawing were high in the 7 cm/10 min (cooling rate: -4 to -22 degrees C/min) and 10 cm/15 min groups (cooling rate: -6 to -10 degrees C/min). On comparison of frozen semen prepared by the plunging method (7 cm/10 min) with frozen semen prepared by the simple freezer method, sperm motility and viability were significantly higher for the frozen semen prepared by the plunging method. The cooling rate in freezing was higher for the simple freezer method (cooling rate: -6 to -50.9 degrees C/min) than the plunging method. Based on these findings, horizontal placement of canine semen straws above LN2 to reduce the temperature at a slow cooling rate of about -10 degrees C/min, followed by plunging into LN2 after sensitization for 10-15 min, provides good semen qualities after thawing.  相似文献   
50.
In order to find new utilization method of woody wastes, we examined the bioactivities of extracts from branch heartwood of Chamaecyparis obtusa (hinoki) and compared to extracts from trunk heartwood. The bioactivities examined were antifungal activities against four fungi (Trametes versicolor, Fomitopsis palustris, Trichoderma virens, Rhizopus oryzae), and bioassay with brine shrimp (Artemia salina) which shows any allelopathic activities not measurable with fungi. Antifungal activities were observed in the hexane and ethyl acetate extracts of branch and trunk heartwood. The hexane and ethyl acetate extracts of branch and hexane extract of trunk showed strong lethality against brine shrimp. The yields of the active extracts of branch were much more than that of trunk. The identified compounds in the active extracts of branch were germacra-1-(10),5-dien-4??-ol, t-cadinol, t-muurolol, hinokiresinol, and hinokinin. Hinokiresinol and t-muurolol showed strong antifungal activities. Hinokiresinol showed bioactivities against T. virens, R. oryzae and brine shrimp. Germacra-1-(10),5-dien-4??-ol was lethal to brine shrimp. Germacra-1-(10),5-dien-4??-ol and hinokiresinol were minor components in trunk heartwood, but major components in branch. These qualitative and quantitative results suggest that the branch heartwood could be a valuable chemical resource because it contains large amounts of antifungal and allelopathic compounds.  相似文献   
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