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951.
952.
Surface-sterilized leaf disks of horse-radish (Armoracia lapathifolia) were immersed in a suspension of Agrobacterium rhizogenes harboring the root-inducing plasmid (pRi) and cultured on a solid medium. Within about 10 days after inoculation, adventitious roots (hairy roots) emerged from the leaf disks. No roots emerged from the uninoculated leaf disks. The excised hairy roots grew vigorously in the dark and exhibited extensive lateral branches in the absence of phytohormones. When the hairy roots were moved into the light, numerous adventitious buds thrust out of the roots within about 10 days, and they developed into complete plants (R0 generation). R0 plants revealed leaf wrinkle. Root masses of cultured R0 plants were of two types. One had fibrous roots only and the other had both fibrous and tuberous roots Leaf disks of the R0 plants proliferated adventitious roots (R1 generation) on a solid medium after 1–2 weeks of culture. Phenotypical characters of the R1 roots were the same as those observed with the initial hairy roots. The T-DNA sequences of pRi were detected within DNA isolated from the hairy roots and their regenerants.  相似文献   
953.
Copper is the essential transition element for nitrous oxide respiration in Pseudomonas perfectomarinus. Two novel kinds of copper proteins were detected in this organism. Their distribution was studied under different growth conditions and in other pseudomonads, as well as their association with N2O reduction of intact cells. A low molecular mass copper protein (M r 38,000) with a single absorption band at 340 nm (oxidized form), was found only in P. perfectomarinus and was not required for N2O reduction. N2O respiration was consistently associated with a high molecular mass copper protein (M r 120,000) in P. perfectomarinus, Pseudomonas stutzeri, and in strains of Pseudomonas fluorescens that were capable of this type of respiration. The oxidized protein was violet to pink with absorption bands at 350, 480, 530, 620, and 780 nm. Pseudomonas chlororaphis and Pseudomonas aureofaciens which did not respire with N2O as electron acceptor, did not contain the novel type of copper protein. Cytochrome patterns were compared in these denitrifying pseudomonads to search for the physiological electron carrier to N2O reductase. The content and nature of the soluble c-type cytochromes depended strongly on the species and the particular growth condition.Abbreviations M r relative molecular mass  相似文献   
954.
Members of a series of macrocyclic bis(bibenzyl) riccardin-class derivatives were found to exhibit antibacterial activity towards methicillin-resistant Staphylococcus aureus (anti-MRSA activity). Structure–activity relationship (SAR) studies were conducted, focusing on the number and position of the hydroxyl groups. The minimum essential structure for anti-MRSA activity was also investigated.  相似文献   
955.
Dietary campest-5-en-3-one (campestenone), an oxidized derivative of campesterol, significantly reduced visceral fat weight and the concentration of triacylglycerol in serum and liver of rats. Dietary campestenone dramatically increased the activities and the mRNA expressions of mitochondrial and peroxisomal enzymes involved in β-oxidation in the liver. Campestenone activated human peroxisome proliferator-activated receptor (PPAR) α as determined using the novel GAL4 ligand-binding domain chimera assay system with coactivator coexpression. In contrast, dietary campestenone reduced the activities and the mRNA expressions of enzymes involved in fatty acid synthesis, except for the malic enzyme. Dietary campestenone decreased the sterol regulatory element binding protein-1 (SREBP-1) mRNA level. Energy expenditure was significantly higher in the feeding of campestenone in rats. Dietary campestenone reduced hepatic cholesterol concentration and increased fecal excretion of neutral steroids originated from cholesterol. Lymphatic absorption of cholesterol was reduced by the coadministration of campestenone in rats cannulated in the thoracic duct. These observations suggest a possibility that campestenone has an ability to prevent coronary heart disease by improving obesity and abnormality of lipid metabolism.  相似文献   
956.
Action spectra of light-induced membrane hyperpolarization andphotosynthetic oxygen evolution were determined in cells ofEgeria densa. Since both spectra were similar, photosyntheticpigments are assumed to be involved in the light-induced membranehyperpolarization. However, the saturation levels of light fluenciesdiffered greatly between the two light reactions. Light-inducedhyperpolarization reached the maximum level at a light fluenceless than one-tenth that needed for saturation of photosynthesis. (Received June 5, 1985; Accepted November 13, 1985)  相似文献   
957.
958.
One of the leading risk factors for atherosclerosis is obesity, which is commonly caused by a nutrient-rich Western-style diet, sedentary behaviors, and shift work. Time-restricted (TR) feeding and intermittent fasting are both known to prevent overweight and adiposity, improve glucose tolerance, and decrease plasma cholesterol in high-fat diet-induced obese mice. Here we examined the overall effects of TR feeding of a Western diet (fat, 40.5 Kcal%; cholesterol, 0.21 g%) using 8-week-old Apoe−/− mice. Mice were assigned into three groups: (1) an ad libitum (AL) group fed an AL Western diet, (2) a TR group with restricted access to a Western diet (15 h/day, 12:00 to 3:00 Zeitgeber time [ZT]); and (3) an Ex/TR group fed a TR Western diet and subjected to physical exercise at 12:00 ZT. Mice in the AL group gained body weight rapidly during the 14-week observation period. With TR feeding, excessive weight gain, liver adiposity, visceral fat, and brown adipose tissue volume were effectively suppressed. Although TR feeding failed to decrease Oil Red O-stained aortic plaques in Apoe−/− mice, physical exercise significantly decreased them. Neither TR feeding with exercise nor that without exercise decreased the mean area under the curve of the plasma cholesterol level or the fasting plasma glucose. Collectively, TR feeding of a Western diet prevented the development of obesity but failed to ameliorate atherosclerosis in Apoe−/− mice.  相似文献   
959.
Mulberry 1-deoxynojirimycin (DNJ, a potent α-glycosidase inhibitor) has been investigated thoroughly for its analytical methods and therapeutic potential against diabetes, whereas little attention has been given to other iminosugars such as 2-O-α-d-galactopyranosyl-DNJ (GAL-DNJ) and fagomine. For instance, concentration and composition of these iminosugars in mulberry leaves as well as sericulture products have not been fully characterized due to lack of suitable analytical methods. Here we developed a simultaneous determination method for DNJ, GAL-DNJ, and fagomine using hydrophilic interaction chromatography (HILIC) with tandem mass spectrometry (MS/MS). When mulberry leaf extracts were subjected to HILIC-MS/MS with multiple reaction monitoring (MRM), individual iminosugars could be separated and detected. The developed method is sufficiently sensitive for determining iminosugars in mulberry leaves as well as silkworms, providing new information (e.g., different amounts of iminosugars in mulberry leaf varieties; high DNJ and low GAL-DNJ in the silkworm body, especially in the blood) that is useful for producing iminosugar-rich products for nutraceutical purposes.  相似文献   
960.
The wood of Conocarpus erectus contains conocarpol and 2′-methoxyconocarpol, simple 1,4-diarylbutane-type lignans, and conocarpan, a lignan of the dehydrodi-isoeugenol type.  相似文献   
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