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61.
Extraction of Stevia satureiaefolia furnished the flavonoids cirsimaritin and eupatorin and the guaianolide eupahakonenin B. 相似文献
62.
Different criteria have been suggested for decisions on character state recognition for morphological characters showing continuous variation from taxon to taxon. A method proposed byMishler andDe Luna seeks to recognize as many character states as the groups of taxon means that are revealed by an analysis of variance (ANOVA) followed by multiple range tests. We apply this method as a guide in decisions of selecting taxonomic characters in species of theBletia reflexa complex. Seven species of the complex, represented by 156 individuals belonging to 54 populations, were the terminal taxa of the study. Character state codes were assigned to 20 characters. These characters together with 12 non-quantitative characters were incorporated into cladistic analyses. Results indicate that the complex is monophyletic only under one outgroup combination. 相似文献
63.
The therapeutic value of prenylamine in angina pectoris was tested in two ways. Fourteen patients received 270 mg. of prenylamine per day for one month. This was preceded and followed by one month of placebo therapy. Assessment was made, first by twice-monthly treadmill exercise tests, and secondly by daily records of anginal attacks and nitroglycerin usage. The occurrence of pain and electrocardiographic changes during treadmill exercise was apparently uninfluenced by the drug. However, there was a reduced incidence of spontaneous angina and nitroglycerin usage during the month on prenylamine by contrast with either month on placebo (p <0.05). 相似文献
64.
Estrogen receptor β regulates the tumoral suppressor PTEN to modulate pituitary cell growth
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![点击此处可从《Journal of cellular physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
65.
V. Regalado F. Perestelo A. Rodríguez A. Carnicero F. J. Sosa G. De la Fuente M. A. Falcón 《Applied microbiology and biotechnology》1999,51(3):388-390
Laccase, aryl-alcohol oxidase and superoxide radicals were detected in ligninolytic cultures of Fusarium proliferatum. Enzyme activities were present during the secondary metabolism and seen as single protein bands after non-denaturing electrophoresis.
In contrast, superoxide radicals were detected during primary growth, correlating with maximal lignin mineralization. Moreover,
ligninolysis decreased when scavengers of both superoxide and hydroxyl radicals were added to cultures, indicating that activated
oxygen species are involved in lignin degradation.
Received: 12 October 1998 / Accepted: 24 October 1998 相似文献
66.
Reproductive cycle and maternal–embryonic nutritional relationship of shovelnose guitarfish Pseudobatos productus in the Gulf of California
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A. E. Romo‐Curiel O. Sosa‐Nishizaki J. C. Pérez‐Jiménez M. C. Rodríguez‐Medrano 《Journal of fish biology》2017,90(3):889-905
Samples of the shovelnose guitarfish Pseudobatos productus were collected on board a vessel and at landings of artisanal commercial fisheries in the Gulf of California from May 2004 to June 2007. Samples of 650 females, 2047 embryos and 484 uterine eggs were examined. The reproductive cycle is annual, ovulation and parturition occur in July, the uterine eggs are in diapause for 9 months (July–March) before an accelerated growth of embryos of 3 months. Histological analyses of the uterine wall of pregnant females suggested that no secretions were used for embryo nourishment. The standard percentage of water content was 48·6% in fertilized eggs and 80·75% in full‐term embryos. Dry mass loss during embryonic development was 16·3% and the chemical balance of development was 0·84. This indicates that P. productus is a strictly lecithotrophic, viviparous species, that makes no maternal contribution of nutrients during embryonic development. 相似文献
67.
A group of representative species of the genus Puya was studied to determine if there are allometric relationships between vegetative and floral parts, whether these relationships
correlate with their pollination system and if plant size is correlated with elevation and latitude. Fifty-three species representing
the morphological variation and distribution of the genus were studied. Total plant height, as well as leaf, inflorescence,
petal and sepal length were measured and these data subjected to univariate and multivariate analyses. To test for correlation
between plant size and altitudinal and latitudinal distribution, ANOVAs were performed. When the pollination system of a species
is known, additional multivariate and univariate analyses were also performed. The results indicate that the characters studied
are correlated with a size component, exhibiting positive allometry for sepal and petal length and negative allometry for
leaf length. Inflorescence length is an isometric character. There was no significant correlation between plant size and altitudinal
or latitudinal distribution. The ANOVAs show that the only character correlated to pollinator type was petal length. Small
plants with small flowers are correlated to pollinators such as insects, while medium to large plants with medium to large-sized
flowers are correlated with pollinators such as birds and bats. Large plants have small flowers, that are more evident and
attract more pollinators. 相似文献
68.
Sosa OA de Nadra MC Farías ME 《Journal of industrial microbiology & biotechnology》2008,35(8):851-857
We have evaluated the induction of the flocculent phenotype of Kloeckera apiculata by glucose mc1 and propose a pathway involved in carbohydrate flocculation induction. Pulses of glucose were given to cells growing in glucose-poor medium (2 g l(-1)) and the flocculation percentage was measured. To elucidate the mechanism involved in flocculation induction, cycloheximide was injected into the cultures 120 min before the glucose pulse. 2,4-Dinitrophenol or cAMP was added to the media instead, or simultaneously with glucose, while a protein kinase A (PKA) inhibitor was added 30 min before the glucose pulse. With 20 and 50 g l(-1) glucose pulse, the yeast flocculation percentage arises to 55 and 65%, respectively. The quantity of proteins and the reflocculating capacity of a lectinic protein extract from the yeast cell wall increase as the concentration of glucose pulse was higher. Cycloheximide prevented the glucose-induced flocculation, while cAMP or 2,4-dinitrophenol increased it 4- and 5-fold, respectively. PKA inhibitor completely prevented the glucose induction flocculation. The flocculent phenotype of K. apiculata mc1 was induced by glucose and the mechanism seems to imply de novo protein (lectin) synthesis via the PKA transduction pathway. This work contributes to the elucidation of the mechanism involved in flocculation induction by glucose of a non-Saccharomyces wine yeast, K. apiculata, which has not been reported. The induction of flocculation by glucose could be a biotechnological tool for the early removal of the indigenous microorganisms from the grape must before the inoculation of a selected starter strain to conduct the alcohol fermentation. 相似文献
69.
70.
Miguel A. Gonz��lez-P��rez Pedro A. Sosa Elisabeth Rivero Edna A. Gonz��lez-Gonz��lez Agust��n Naranjo 《Annals of botany》2009,103(1):79-86