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71.
Genetic Resources and Crop Evolution - Coffee is one of the most important agricultural commodities worldwide, significantly contributing to the economies of many coffee-producing countries....  相似文献   
72.
A new stereoisomer of an araguspongine/xestospongin alkaloid, named araguspongine M (1), has been isolated together with 12 known compounds, araguspongines B (2) and D (3), dopamine, three galactosyl diacylglycerols, 24-methyl cholesterol, 5,6-dihydrocholesterol, β-sitosterol, and three 5α,8α-epidioxy sterols (11–13), from the marine sponge Neopetrosia exigua (formerly Xestospongia exigua) collected in Palau. The structure of 1 was assigned on the basis of its spectral data analysis. This is the first report on the isolation of dopamine from a marine sponge. This compound may be produced by an endosymbiotic Synechococcus-like cyanobacterium. Compounds 1–3 and 11–13 showed cytotoxicity against HL-60 at IC50’s of 5.5, 5.5, 5.9, 22.4, 9.5, and 9.6 μM, respectively. The possible biosynthesis origin of the isolated metabolites is discussed.  相似文献   
73.
The carbohydrates in soil organic matter seem to be derived from undecomposed or partially decomposed plant and microbial residues, In soil, these carbohydrates exist chiefly in such from as polysaccharide hemicellulose, and their polyuronide has been the chief object of investigation1)-3). In various soil, the polyuronide is found in a large quantity in fulvic fraction of soil organic matter and has been considered as important in connection with the physical structure of soil4),5). According to Lynch 5), the carbohydrate content of humic acid is markedly smaller than that of fulvic acid. His work also indicates that a' considerable change is noted in the content and composition of the carbohydrate in humic acid because of the addition of some organic substances to the soils, or of the cultivation of virgin soils. Further, some investigators7) believe that uronic acid is introduced into the aromatic structure of the humic acid by changing into pentose and furan. Accordingly, it seems that the role of carbohydrate in the formation of soil humic acid should not be overlooked.  相似文献   
74.
75.
This study investigated the effects of skim milk on the quality and fertility of boar spermatozoa under long‐term chilled preservation. Semen samples were stored in Modena solution supplemented with 0 (control) to 50 mg/mL skim milk at 5°C for 4 weeks; spermatozoa stored with 7.5 and 15 mg/mL of skim milk (7.5‐SM and 15‐SM groups, respectively) exhibited significantly higher motility indices than those of the control group up to 3 weeks (P < 0.05), and the 7.5‐SM group showed improved motility indices even after 4 weeks (P < 0.05). In vitro fertilization using spermatozoa in the 7.5‐SM and 15‐SM groups stored at 5°C for 2 weeks showed significantly higher fertilization rates of spermatozoa and the development rates to blastocyst than the control group (P < 0.05), and the 7.5‐SM group showed similar rates of fertilization and blastocyst formation in the fresh non‐stored spermatozoa group. After artificial insemination using spermatozoa stored for 2 weeks in the 7.5‐SM group, healthy piglets were obtained. Boar spermatozoa can be stored at 5°C in a Modena solution containing skim milk. Supplementation of 7.5 mg/mL skim milk improves boar spermatozoa motility and fertility even after liquid preservation at 5°C for 2 weeks.  相似文献   
76.
To improve embryo development in bovine separated blastomeres, we evaluated applicability of co‐culture with intact embryos. The morphological quality of blastocysts derived from separated blastomeres and rate of blastocyst formation were only slightly increased when the cells were co‐cultured with intact embryos, which did not provide significant differences when statistically analyzed. However, the cell count of inner cell mass (ICM), trophectoderm (TE) and total number of cells in Day 8 blastocysts were significantly higher when the cells were co‐cultured with the intact embryos than those with the cells cultured individually (P < 0.05). Transfer of four monozygotic pairs of blastocysts derived from the cells co‐cultured with intact embryos led to three pregnancies even when the blastomeres were produced by in vitro maturation and in vitro fertilization of oocytes collected by ovum pick‐up from elite cows. These results suggest that co‐culturing with intact embryos may enhance development of bovine separated blastomere.  相似文献   
77.
It was previously revealed that esculeoside A, a new glycoalkaloid, and esculeogenin A, a new aglycon of esculeoside A, contained in ripe tomato ameliorate atherosclerosis in apoE-deficent mice. This study examined whether tomatidine, the aglycone of tomatine, which is a major tomato glycoalkaloid, also shows similar inhibitory effects on cholesterol ester (CE) accumulation in human monocyte-derived macrophages (HMDM) and atherogenesis in apoE-deficient mice. Tomatidine significantly inhibited the CE accumulation induced by acetylated LDL in HMDM in a dose-dependent manner. Tomatidine also inhibited CE formation in Chinese hamster ovary cells overexpressing acyl-CoA:cholesterol acyl-transferase (ACAT)-1 or ACAT-2, suggesting that tomatidine suppresses both ACAT-1 and ACAT-2 activities. Furthermore, the oral administration of tomatidine to apoE-deficient mice significantly reduced levels of serum cholesterol, LDL-cholesterol, and areas of atherosclerotic lesions. The study provides the first evidence that tomatidine significantly suppresses the activity of ACAT and leads to reduction of atherogenesis.  相似文献   
78.
Seven major peptides belonging to the crustacean hyperglycemic hormone family were purified from the sinus gland located in the eyestalk of the kuruma prawn Marsupenaeus japonicus, and their effects on vitellogenin gene expression were examined using the ex vivo ovary incubation system. Six molecular species of crustacean hyperglycemic hormone, Pej-SGP-I, -II, -III, -V, VI, and VII, displayed significant inhibitory effects on vg expression with almost the same efficacies, whereas Pej-SGP-IV (known as molt-inhibiting hormone) did not. Two chromatophorotropic peptides, red pigment-concentrating hormone and pigment-dispersing hormone, which were also present in the sinus glands, did not have a clear effect on the gene expression levels in this incubation system. These results suggest that the six crustacean hyperglycemic hormones are potentially capable of acting as vitellogenesis-inhibiting hormones in M. japonicus.  相似文献   
79.
Ecto-apyrase(s) participates in cell-wall-associated defense through ATP hydrolysis. Here we analyzed Medicago truncatula genes through cDNA screening and in silico analyses against known databases. This study revealed seven genes, five of which (MtAPY1;1 to MtAPY1;5) are members of a legume-specific family, whereas two genes (MtAPY2;1 and MtAPY2;2) are close to those in other plants. Agrobacterium-based transient expression in Nicotiana benthamiana, combined with a c-myc epitope tag technology, confirmed that the MtAPY1;1 is a secreted protein. Transient expression of MtAPY1;1 in leaves of N. benthamiana restricted disease development by a virulent fungus, suggesting a role in disease resistance.  相似文献   
80.
The GCAs are new tetraploid interspecific hybrids developed in Madagascar from Coffea eugenioides, C. canephora and C. arabica. Selected GCA having genotype UF1023 contained 0.37% DW caffeine and no detectable theobromine in green beans. Low caffeine accumulation in GCA plants is due mainly to the low biosynthetic activity of purine alkaloids, possibly the extremely weak N-methyltransferase reactions in caffeine biosynthesis. No significant catabolic activity of caffeine was found in GCA-UF1023, in common with almost all coffee plants including C. arabica.  相似文献   
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