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1.
2.
Abstract

Context: Mammary and placental 17β-hydroxysteroid dehydrogenase type 1 (17βHSD1).

Objective: To assess the impact of testosterone, tibolone, and black cohosh on purified mammary and placental 17βHSD1.

Materials and methods: 17βHSD1 was purified from human mammary gland and placenta by column chromatography, its activity was monitored by a radioactive activity assay, and the degree of purification was determined by gel electrophoresis. Photometric cofactor transformation analysis was performed to assess 17βHSD1 activity without or in presence of testosterone, tibolone and black cohosh.

Results: 17βHSD1 from both sources displayed a comparable basal activity. Testosterone and tibolone metabolites inhibited purified mammary and placental 17βHSD1 activity to a different extent, whereas black cohosh had no impact.

Discussion: Studies on purified enzymes reveal the individual action of drugs on local regulatory mechanisms thus helping to develop more targeted therapeutic intervention.

Conclusion: Testosterone, tibolone and black cohosh display a beneficial effect on local mammary estrogen metabolism by not affecting or decreasing local estradiol exposure.  相似文献   

3.
The main aroma components of oolong and black tea, linalool and four diastereomers of linalool oxides (LOs), were enantioselectively isolated by capillary gas chromatography, using a column coated with an optically active liquid phase, permethylated β-cyclodextrin.

The R/S ratio varied among linalool and LOs, and among the different types of tea, the ratio for a particular compound also being different. However, the complete patterns of R/S ratio were similar in the semi-fermented and fermented teas, respectively.

Using a specific cultivar of black tea, the R/S ratio for each of the five compounds was compared in the free state in black tea with that of an aglycone of the glycoside in fresh tea leaves or in black tea. While the e.e. values of the compounds varied, those for a specific compound were similar, except for linalool, regardless of their free or combined state.

These results show that LOs are not directly transformed from linalool, but are formed enzymatically from glycoside precursors.  相似文献   

4.
S-Methylmethionine (MMS, an anti-ulcer factor, Vitamin u) was determined in the extracts of various kinds of teas, such as green teas, black teas and oolong teas, using an amino acid analyzer for physiological-fluid analysis or for rapid analysis. MMS in the column eluates was confirmed to be dimethyl sulfide by a gas-chromatographic method with a flame photometric detector. The quantity of MMS obtained from the various green teas depended on the quality and the freshness, i.e.fresh, high-quality gyokuro, 15.7 to 24.5 mg%; fresh sen-cha, 7.0 to 10.3 mg%; and the other green teas 1 to 6mg%. Oolong tea and black tea did not contain MMS.

The extraction conditions for and the heat-stability of MMS were also discussed.  相似文献   

5.
Abstract

The effect of endophytic Pseudomonas fluorescens isolates Endo2 and Endo35 on induced systemic disease protection against dry root rot of black gram (Vigna mungo L. Hepper) caused by Macrophomina phaseolina was investigated under glasshouse conditions. When the bacterized black gram plants were inoculated with dry root rot pathogen, the activities of peroxidase (PO), polyphenol oxidase (PPO), phenylalanine ammonia-lyase (PAL) were stimulated in addition to accumulation of phenolics and lignin. Activity of phenylalanine ammonia-lyase (PAL) reached the maximum 24 h after pathogen challenge inoculation, whereas the activities of PO and PPO reached the maximum at 72 h and 48 h, respectively. Isoform analysis revealed that a unique PPO3 isozyme was induced in bacterized black gram tissues inoculated with the pathogen. Phenolics were found to accumulate in bacterized black gram tissues challenged with M. phaseolina one day after pathogen challenge. The accumulation of phenolics reached maximum at the third day after pathogen inoculation. Similar observation was found in the lignin content of black gram plants. In untreated control plants, the accumulation of defence enzymes and chemicals started at the first day and drastically decreased 3 days after pathogen inoculation. These results suggest that induction of defense enzymes involved in phenylpropanoid pathway and accumulation of phenolics and PR-proteins might have contributed to restricting invasion of Macrophomina phaseolina in black gram roots.  相似文献   

6.

Cenococcum geophilum Fr., one of several ectomycorrhizal species associated with black pine (Pinus thunbergii Parl.), is dominant in the coastal forests of Japan, even under adverse abiotic environmental conditions. In these forests, many tonnes of Sumipine® (fenitrothion) are applied every year to protect P. thunbergii from pine wilt disease, which is transmitted by a beetle. Here, we examined the effect of this insecticide on the species of fungi found as ectomycorrhizae on naturally regenerated P. thunbergii seedlings collected from coastal forest sites that had or had not been sprayed with fenitrothion. The proportion of C. geophilum ectomycorrhizae on black pine root tips was significantly higher in areas where fenitrothion had been applied than in areas where it had not. We measured the in vitro mycelial growth of C. geophilum as well as other ectomycorrhizal fungi of coastal black pine, Rhizopogon roseolus (Corda) Th. Fr. and Pisolithus arhizus (Scop.) Rauschert, at three levels of fenitrothion (density: 1.32 g/cm3), i.e., 0, 0.1 and 0.2 mL L?1. The growth of all three species decreased significantly as the fenitrothion dosage increased. However, the reduction of mycelial growth in response to fenitrothion was lower in C. geophilum than in the other two species. These results suggest that C. geophilum has a high tolerance for fenitrothion, which may explain its dominance over other ectomycorrhizal species in coastal forests in Japan where fenitrothion is routinely sprayed.

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7.
The relationship between the ultrasonic acoustic emission (AE) and the needle water potential in field-grown Japanese black pine,Pinus thunbergii, and excised-pine shoots was investigated in summer. The AE technique was employed as a reliable indicator of cavitation events in the water columns of xylem tracheids even under field conditions. In excised shoots. AE events detected when the needle water potential fell below about-0.9 MPa. In the case of field-grown pine trees, however, relatively few AE event were detected when needle water potential was lower than-0.9 MPa. This suggests that the occurrence of cavitation events in Japanese black pine growing under field conditions is comparatively rare, even in summer.  相似文献   

8.
《Plant Ecology & Diversity》2013,6(3-4):383-392
Background: Arctic lichens and mosses are covered by snow for more than half the year and are generally considered as being dormant for most of this period. However, enhanced frequency of winter warming events due to climate change can cause increased disturbance of their protective subnivean environment.

Aim: To further understand cryptogamic responses to midwinter warming we compared the ecophysiological performance of one lichen and one moss species during a simulated warming event.

Methods: We measured photosynthesis and dark respiration in samples of the moss Hylocomium splendens and the lichen Peltigera aphthosa removed from under snow, and on natural refreezing after the warming event, which was simulated by using infrared heaters suspended above the ground.

Results: The moss exposed to light at +5 °C immediately after removal from their subnivean environment and from warmed plots showed positive net gas exchange within 332 s; the lichen required 1238 s. Photosynthesis and nitrogen fixation rates were equal to that, or higher than, during the preceding growing season. Upon refreezing after the event, moss photosynthesis declined considerably.

Conclusions: The moss, and to a lesser extent the lichen, may contribute to subnivean midwinter ecosystem respiration, and both are opportunistic, and can take advantage of warmer winter phases for photosynthesis and growth. This ought to be taken into account in vegetation change projections of cryptogam-rich ecosystems.  相似文献   

9.
The cDNA fragments of hnRNPA2/B1 were cloned from the giant panda and black bear using RT-PCR method, which were, respectively, 1029bp and 1026bp in length encoding 343 and 341 amino acids. Analysis indicated the cDNA cloned from the giant panda encoded variant B1 while the cDNA cloned from black bear encoded variant A2.

Analyzing the hnRNPA2B1 peptide of the giant panda and black bear, 76 glycine residues and 86 glycine residues were, respectively, found, and moreover, most glycine are concentrated in the latter halves of the hnRNPA2B1 peptides. Functional sites prediction also showed many N-myristoylation sites existed in the glycine-rich domain, which is probably related to the role of telomere maintenance.

From base bias and substitution analysis, we can conclude that the ORF of hnRNPA2/B1 biased G while hated C, and transition of the third site did not achieve the level of saturation.

Orthology analysis indicated that both the nucleotide sequence and the deduced amino acid sequence showed high identity to other 26 hnRNPA2/B1 sequences from mammals and nonmammals reported. These sequences were used to construct phylogenetic trees employing the NJ method with 1000 bootstrap, and the obtained tree demonstrated similar topology with the classical systematics, which suggested the potential value of hnRNPA2/B1 in phylogenetic analysis.

This report will be the first step to the study function of hnRNPA2/B1 in the giant panda and black bear, and will provide a scientific basis to disease surveillance, captive breeding, and conservation of the endangered species.  相似文献   

10.

The famously diverse body coloration of cichlid fish serves communicative functions in mating and social interactions including competition for resources. Here, we examined the effects of a color pattern trait—the width of a yellow bar on a black body—on territorial competition in males and females of a color variant (“Ikola”) of the Lake Tanganyika cichlid Tropheus. First, measuring integumentary carotenoid concentrations in the yellow and black body regions, we established that wider yellow bars require more carotenoids allocated to body coloration. However, we also detected high carotenoid concentrations in the black body regions (>?100 µg/g fresh skin), raising questions about the function of non-displayed integumentary carotenoids. Behavioral experiments showed that fish with wider bars were quicker to explore an unfamiliar area of the tank. In experiments including presentations of fish dummies, the bar width of ‘territorial’ dummies had no effect on the latency time which test fish took to intrude into the dummies’ territories. However, male test fish performed fewer aggressive acts against wide-barred than against narrow-barred dummy competitors. Our results suggest that intimidation by wide bars as well as correlations between bar width and explorative behavior may contribute to mediating success in territorial Tropheus “Ikola”.

  相似文献   

11.
P.R. Evans 《Bird Study》2013,60(4):262-264
Birds of West Central and Western Africa. Vol. 2. By C. W. Mackworth- Praed and C. H. B. Grant. Longman. 1973. 818 pp., 93 colour-plates, hundreds of distribution maps. Price £8.00., by L. A. Batten

A Guide to the Birds of Wales. David Saunders. Constable &; Co. Ltd, London. 1974. 341 pp. Many photographs and sketch maps. Price £2.50., by Chris Mead

The World of an Estuary. Heather Angel. Faber and Faber, London. 1975. 128 pp., 50 black and white photographs. Price £1.95., by A. J. Prater

Scarce Migrant Birds in Britain and Ireland. Dr J. T. R. Sharrock, with drawings by P. J. Grant. T. &; A. D. Poyser Ltd., Berkhamsted. 1974. 26 plates. Price £3.80., by D. E. Glue

The Buzzard. Colin R. Tubbs. David and Charles, Newton Abbot. 1974. 199 pp., 17 photographs and 11 figures. Price £4.75., by Chris Mead

Birds of the Yorkshire Coast. Richard Vaughan. Hendon Publishing Co. Ltd., London. 1974. 96 pp. 77 plates. Price £1.70 hardback, £1.20 paperback., by H. B. Ginn

The Naturalist in Majorca. James D. Parrack. David and Charles, Newton Abbot. 1973. 224 pp., 32 black and white plates and 15 line drawings. Price £3.95., by L. A. Batten

Feathers Plain and Fancy. Hilda Simon. Frederick Muller, London. 1973. (First published 1969.) Viking Press, New York. 126 pp., many colour and black and white illustrations by the author. Price £2.00., by H. B> Ginn

A Revised Check-List of the Maltese Islands. By C. De Lucca. E. W. Classey Ltd, Hampton, Middlesex, 1969. 95pp. Price £0.75.

Die Vögel des Bodenseegebietes. By H. Jacoby, G. Knötzsch and S. Schuster. Supplement to Vol. 67 of Der Ornithologische Beobachter, 1970. 260pp. 16 black and white plates.

Die Vogelwelt der Limmattal und Zürichseeregion. By W. Knopfli. Supplement to Vol. 68 of Der Ornithologische Beobachter, 1971. 174pp. 4 colour plates.  相似文献   

12.
Summary The author reports on the clinical and mycological studies of a case of black-grain maduromycosis in a woman from Santa Maria (Province of Catamarca, Argentine).Cultures of black grains in Sabouraud medium have developed colonies ofMadurella mycetomi and also ofMadurella grisea Mackinnon, Ferrada &Montemayor, 1949.The author questioned, which of the two species is the etiological agent in the present case and he concluded that the microscopic aspect of the black grain permits to suppose thatMadurella mycetomi is the agent in this case.

En homenaje al Prof. Tibor Benedek.  相似文献   

13.
The volatile components extracted from fresh tea leaf, fermented leaf and black tea were analysed by gas chromatography.

Quantitative difference in the composition of essential oils was observed between fresh leaf and manufactured black tea; the former was rich in alcohols, whereas the latter in aldehydes and acids.

During fermentation process the following components mainly brought about changes: n-capronaldehyde (4.1 times after fermentation for 3hrs.), trans-2-hexen-l-al (13.2 times) and cis-3-hexenoic acid (1.2 times) increased, but n-hexylalcohol (0.7 time), cis-3-hexen-l-ol (0.7 time) and methylsalicylate (0.8 time) decreased.

These changes during fermentation were scarcely carried out in nitrogen atmosphere.  相似文献   

14.
15.
Abstract

Preliminary observations on the submicroscopic structure of the endospermic starch granules in TRITICUM DURUM desf. (The electronic transparency of the starch granules). — The starch granules of Triticum durum Desf. kernels have been examined by electron microscopy.

The high degree of transparency of the granules appears to depend upon the regular disposition of the structural units, while their opacity probably is in relation with their orderless arrangement. The opacity of amorphous portions of the layers, of the median fissure and of the black bands seems to be in relation with the amorphous condition of such formations.

The black bands and the bubbles which have been considered respectively as protein layers and as the result of enzymes action, are only artifacts. The bubbles are interpreted as pyrodestrines.  相似文献   

16.

This study deals with the determination of germinability of black medick (Medicago lupulina L.) seeds in conditions of different drought intensity induced by different concentrations of PEG 8000 solutions (0.2; 0.4; 0.6 mol). Four batches of seed were tested (Ekola 2–5). At the same time, the influence of boron, some other elements (N, P, K, Ca, Mg, Zn, Cu, Mn) and compounds (starch, lipids and sugars) contents in black medick seeds on their germinability (percentages of germinated, dead and hard seeds) was evaluated. The effect of drought was manifested by germination which was reduced max. by 8% as compared with the control variant and was only partially significant. Statistically significant (P?<?0.01) negative correlations (R?=?? 0.64) were recorded between germinability and the boron content in the seeds, and positive correlations were found between the percentages of hard seeds and the boron content in the seeds. The results show that the higher content of boron in the seeds of black medick increases the proportion of hard seeds at the expense of the germinated seeds percentages.

  相似文献   

17.
Abstract

Crude root extracts of the black beetle-resistant legumes red clover, white clover, lupin, Lotus pedunculatus, and lucerne significantly reduced feeding by 3rd-instar black beetle larvae when incorporated in an artificial medium containing a strong feeding stimulant. The same extracts were toxic when administered orally. Lucerne and L. pedunculatus contain particularly active feeding deterrents and toxins. The root of the black beetle-resistant grass Phalaris aquatica (= P. tuberosa), like that of the susceptible perennial ryegrass, had no effect on larval feeding or survival. Lotus pedunculatus was very much more active against black beetle larvae than L. corniculatus or L. corniculatus × pedunculatus.  相似文献   

18.

Understanding the migratory community dynamics of river networks is important for maintaining lotic system integrity. River animals migrate to their preferred habitats in spatiotemporally heterogeneous river environments. Spring-fed habitats are uniquely characterized by stable temperature and flow regimes, which create suitable spawning habitats for the chum salmon Oncorhynchus keta. O. keta exhibits “run up” to its birthplace for spawning, especially during floods. Because the eggs deposited by this anadromous fish are nutritious and actively consumed by freshwater animals, the location and timing of O. keta spawning events affect the spatiotemporal accumulation of mobile consumers. In this study, we examined changes in temporal population density in spawning O. keta and a mobile consumer (juvenile O. masou masou) in a lowland, spring-fed tributary in northern Japan during a 48.5-mm autumn rainfall event. In both species, population density increased, and then decreased, after the rainfall event. In O. keta, these changes were closely associated with rainfall intensity, whereas in O. masou masou the peak was delayed until 3 days after the rainfall event. A comparison of the gut contents of O. masou masou sampled from a spring-fed tributary and an adjacent non-spring-fed tributary indicated greater consumption of O. keta eggs in the spring-fed tributary. These results suggested that preferential migration of O. keta into spring-fed tributaries for spawning induces subsequent accumulation of juvenile O. masou masou, in turn increasing O. keta egg consumption. These findings improve our understanding of community dynamics during floods in a heterogeneous river network environment.

  相似文献   

19.
Reviews     
A. J. Prater 《Bird Study》2013,60(1):51-52
The Birds of Glamorgan, edited by A. Heathcote, D. Griffin and H. Morrey Salmon. Cardiff Naturalists' Society, 1967 (Annex to vol. 94 of the Transactions of the Society). 30/-. 143 pages, 9 black and white photos, end-paper maps.

Birds of Norfolk, by M. J. Seago. Jarrold & Sons, Ltd., Norwich, 1967. 45 /-. 148 pages, 65 coloured photos, end-paper maps.

The Birds of Huntingdonshire, by C. F. Tebbutt. Published by the author, 1967. 75 pages, map.

A Supplement to the Birds of Cheshire, by T. Hedley Bell. Published by the author (12/16 Booth St., Manchester 2), 1967. 91 pages.

The Birds of the Doncaster District, by R. J. Rhodes. Doncaster and District Orn. Soc. (125 Chequer Avenue, Belle Vue, Doncaster), 1967. 10/-. 101 pages, map.

Pesticides and Pollution, by Kenneth Mellanby. Collins, New Naturalist, London, 1967. 30 /-. 221 pages, 30 photos, 4 in colour.

Man and Environment, by Robert Arvill. Penguin Books, London, 1967. 8/6. 332 pages, 13 black and white photos.

The Wreck of the Torrey Canyon, by Crispin Gill, Frank Booker and Tony Soper. Davis & Charles, Newton Abbott, 1967. 21/-. 128 pages, 31 black and white photos.

Courtship: a zoological study, by Margaret Bastock. Heinemann, London, 1967. 25 /-. 220 pages, 63 text-figures.

The Book of the American Woodcock, by W. G. Sheldon. University of Massachusetts Press, Amherst, Mass., 1967. $8.50. 227 pages,58 figures.

The Whooping Crane: a fight against extinction, by Faith McNulty. Longmans, Green & Co., London, 1967. 30/-. 190 pages, 26 illustrations.

Birds of Australia, A. Rutgers. 2 vols. Methuen, London, 1967. 35/- each. Each with 80 coloured plates from the lithographs of John Gould.  相似文献   

20.
Abstract

In accordance with the European regulation on Invasive Alien Species (IAS), the black cherry tree (Prunus serotina Ehrh.) has recently been indicated as one of the 96 species proposed for the development of the national list of priority invasive alien species in Italy. The species, native to North America, is recognised as one of the most harmful IAS in Europe, given its high spread potential and the associated ecological and economic impacts reported in its alien range. Although P. serotina is recognised as a pest within the EU, plants are still available on the market, confirming intentional introduction as a current potential pathway for this species arrival into new areas. Since a comprehensive overview of the main features characterizing the invasive potential of this species is still lacking, we aim to underpin the high priority status of P. serotina as a IAS of main concern in Italy by outlining the main biological features, pathways and impacts of the black cherry in its secondary range. Management measures to be potentially included in specific action plans are also summarised.  相似文献   

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