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A cholesterol-free diet containing dried powder of Jew's mellow leaves, persimmon leaves or sweet potato leaves respectively at 5% level as dietary fiber was fed to male Sprague-Dawley rats for about one month. The experiment was conducted twice except for sweet potato leaves. In the groups fed the diet mixed with powders of any of the three different dried green leaves, the hepatic cholesterol concentration significantly decreased. Such lowering was not observed in serum cholesterol concentration compared with the control (cellulose) group. A significant increase in fecal weight was observed in all the groups fed the green leaf samples. All the dried green leaves increased fecal excretion of bile acids per gram or per day compared with the control group in both experiments, but only the dried Jew's mellow leaves showed an increased excretion of neutral sterols. These results suggest that lowering of hepatic cholesterol by powdered green leaves is not necessarily due to the same factor, but to the increased fecal excretion of bile acids due to inhibited enterohepatic circulation in animals given these samples.  相似文献   
95.
The aims of this study were 1) to determine whether dairy cows can be induced to ovulate by the treatment with gonadotropin releasing hormone (GnRH) followed by prostaglandin F(2 alpha) (PGF(2 alpha)) during the early postpartum period and 2) to describe their ovarian and hormonal responses according to ovarian status. Cows were divided in two groups and received 10 microg of buserelin followed by 500 microg of cloprostenol 7 days apart starting from 21 (GnRH21, n=7) or around 37 days postpartum (GnRH37, n=7). The groups were further classified according to presence (-CL) or absence (-NCL) of functional corpora lutea (CL) on the day of GnRH treatment (d 0): GnRH21-NCL (n=4), GnRH21-CL (n=3) and GnRH37-CL (n=7). Ovarian morphology was monitored and the concentrations of P(4), E(2), FSH and insulin-like growth factor 1 (IGF-1) were measured. All cows ovulated after administration of GnRH. The P(4) levels of the GnRH21-NCL group from d 0 to d 5 were lower than those of the GnRH21-CL (P<0.05) and GnRH37-CL groups (P<0.01). In contrast, the E(2) levels of the GnRH21-NCL group within d 2 to d 6 were higher (P<0.05) than those of the other groups. Compared with the GnRH37-CL group, the GnRH21-NCL group had more small follicles on d 2 (P<0.05), d 3 (P<0.01) and d 4 (P<0.01) and more large follicles on d 5 (P<0.05). The induced CL and new ovulatory follicles were larger in the GnRH21-NCL group compared with the GnRH21-CL (P<0.001 and P<0.01) and GnRH37-CL groups (P<0.001 and P<0.05). IGF-1 did not differ among the groups. The GnRH21-NCL group had higher FSH levels than the GnRH21-CL (P<0.01) and GnRH37-CL groups (P<0.001) on d 0. Low P(4) and high FSH levels may suggest higher gonadotropin support on the enhanced ovarian morphology of the GnRH21-NCL group. PGF(2 alpha) treatment induced CL regression and subsequent ovulation in 3/4 (75%), 3/3 (100%) and 7/7 (100%) cows in the GnRH21-NCL, GnRH21-CL and GnRH37-CL groups, respectively. In conclusion, a 7-day GnRH-PGF(2 alpha) synchronization protocol can effectively induce dairy cows to ovulate as early as 21 days postpartum, regardless of ovarian status.  相似文献   
96.
Soybean dwarf virus (SbDV) causes serious dwarfing, yellowing and sterility in soybean (Glycine max). The soybean cv. Adams is tolerant to SbDV infection in the field and exhibits antibiosis to foxglove aphid (Aulacorthum solani), which transmits SbDV. This antibiosis (termed “aphid resistance”) is required for tolerance to SbDV in the field in segregated progenies of Adams. A major quantitative trait locus, Raso1, is reported for foxglove aphid resistance. Our objectives were to fine map Raso1 and to reveal whether Raso1 alone is sufficient to confer both aphid resistance and SbDV tolerance. We introduced Raso1 into cv. Toyomusume by backcrossing and investigated the degree of aphid antibiosis to foxglove aphid and the degree of tolerance to SbDV in the field. All Raso1-introduced backcross lines showed aphid resistance. Interestingly, only one Raso1-introduced backcross line (TM-1386) showed tolerance to SbDV in the field. The results demonstrated Raso1 alone is sufficient to confer aphid resistance but insufficient for SbDV tolerance. Tolerance to SbDV was indicated to require additional gene(s) to Raso1. Additionally, Raso1 was mapped to a 63-kb interval on chromosome 3 of the Williams 82 sequence assembly (Glyma1). This interval includes a nucleotide-binding site–leucine-rich repeat encoding gene and two other genes in the Williams 82 soybean genome sequence.  相似文献   
97.
Diploid and triploid intergeneric hybrids obtained by crosses among Gloriosa superba ‘Lutea’ (2n = 2x = 22), G. ‘Marron Gold’ (2n = 4x = 44), Littonia modesta (2n = 2x = 22), and Sandersonia aurantiaca (2n = 2x = 24) were analyzed for their meiotic chromosome pairing in pollen mother cells by genomic in situ hybridization (GISH) with digoxigenin-labeled total DNA of one parent as probe. Chromosomes from each parent could be clearly distinguished in pollen mother cells of all the five intergeneric hybrids by GISH. For three diploid hybrids, L. modesta × G. superba ‘Lutea’ (2n = 2x = 22), L. modesta × S. aurantiaca (2n = 2x = 23) and S. aurantiaca × G. superba ‘Lutea’ (2n = 2x = 23), 0.04?0.27 autosyndetic bivalents (intragenomic pairing of non-homologous chromosomes) and 0.13?0.36 allosyndetic bivalents (intergenomic chromosome pairing) were observed per pollen mother cell, indicating that there are some homologous chromosomal regions within each genome and among the genomes of Gloriosa, Littonia and Sandersonia. Differences in the average number of allosyndetic bivalents per pollen mother cell among different genome combinations may reflect the evolutionary distances among the three genera, and Gloriosa and Littonia may be closely related to each other, while Sandersonia may have relatively distant relationships with Gloriosa and Littonia. For two triploid hybrids, L. modesta × G. ‘Marron Gold’ (2n = 3x = 33) and S. aurantiaca × G. ‘Marron Gold’ (2n = 3x = 34), no allosyndetic bivalents were observed. Based on the results obtained in the present study, possible utilization of the diploid and triploid intergeneric hybrids for further breeding of colchicaceous ornamentals is discussed.  相似文献   
98.
In Japan, there are so many works on mountains soils, most of which have been carried out through the Soil Survey Project on the National Forest (1). Moreover, we have some excellent works on the genesis and classification of alpine soils (2–9). However, the vertical soil zoonality was first verified by Kondo (10), one of the authors of this paper, in the Japan Alps as follows;  相似文献   
99.
Qian W  Miki D  Zhang H  Liu Y  Zhang X  Tang K  Kan Y  La H  Li X  Li S  Zhu X  Shi X  Zhang K  Pontes O  Chen X  Liu R  Gong Z  Zhu JK 《Science (New York, N.Y.)》2012,336(6087):1445-1448
Active DNA demethylation is an important part of epigenetic regulation in plants and animals. How active DNA demethylation is regulated and its relationship with histone modification patterns are unclear. Here, we report the discovery of IDM1, a regulator of DNA demethylation in Arabidopsis. IDM1 is required for preventing DNA hypermethylation of highly homologous multicopy genes and other repetitive sequences that are normally targeted for active DNA demethylation by Repressor of Silencing 1 and related 5-methylcytosine DNA glycosylases. IDM1 binds methylated DNA at chromatin sites lacking histone H3K4 di- or trimethylation and acetylates H3 to create a chromatin environment permissible for 5-methylcytosine DNA glycosylases to function. Our study reveals how some genes are indicated by multiple epigenetic marks for active DNA demethylation and protection from silencing.  相似文献   
100.
Analysis of cellular components at multiple levels of biological information can provide valuable functional insights. We performed multiple high-throughput measurements to study the response of Escherichia coli cells to genetic and environmental perturbations. Analysis of metabolic enzyme gene disruptants revealed unexpectedly small changes in messenger RNA and proteins for most disruptants. Overall, metabolite levels were also stable, reflecting the rerouting of fluxes in the metabolic network. In contrast, E. coli actively regulated enzyme levels to maintain a stable metabolic state in response to changes in growth rate. E. coli thus seems to use complementary strategies that result in a metabolic network robust against perturbations.  相似文献   
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