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71.
A simple method for the rapid separation and quantification of flavone-O- and C-glycosides in A. setacea W. et K. by capillary zone electrophoresis (CZE) with UV detection is described. Using 25 mM sodium borate with 20% (v/v) of methanol (pH 9.3) as running buffer sufficient separation of the analytes was achieved within 19 min. For the quantitative determination isorhamnetin-3-O-rutinoside was used as internal standard. The method was successfully applied to a rapid characterisation of the flavonoid complex and a precise quantification of the single and total amount of the flavonoids in different samples of A. setacea.  相似文献   
72.
Two types of hexactinomyxon spores, Hexactinomyxon type 1 nov. and Hexactinomyxon type 2 nov., are reported from freshwater tubificid oligochaetes, Limnodrilus hoffmeisteri and L. udekemianus. Spores are triradially symmetrical and comprise a spore body, style and 6 caudal processes. The caudal processes arise from the division of each of the 3 valve cells into an equal pair of projections at the base of the style. One of each pair is fused conspicuously to its nearest neighbour for the initial 1/5 to 1/4 of their total length. Distally, each process possesses subsidiary protrusions which are irregularly distributed and irregularly shaped extensions of the valve cell. Scanning electron microscopy of Hexactinomyxon type 2 nov. revealed that these protrusions are a seamless extension of the valve cell wall which branch distally, occasionally laterally, and terminate in a distinct bulbous structure; they also form the terminus of each process. The small subunit ribosomal DNA gene (18S) of both hexactinomyxon types was amplified through a nested PCR, then digested with the restriction enzymes Dde I and Hha I. The resultant cleavage patterns suggested the presence of 2 forms. Subsequent partial sequencing of 18S rDNA confirmed the identification of 2 novel types.  相似文献   
73.
Suppressor of phyA-105 (SPA1) is a phytochrome A-specific signaling intermediate that acts as a light-dependent repressor of photomorphogenesis in Arabidopsis seedlings. SPA1 is part of a small gene family comprising three genes: SPA1-related 2 (SPA2), SPA1-related 3 (SPA3), and SPA1-related 4 (SPA4). Here, we investigate the functions of SPA3 and SPA4, two very closely related genes coding for proteins with 74% identical amino acids. Seedlings with mutations in SPA3 or SPA4 exhibit enhanced photomorphogenesis in the light, but show no phenotype in darkness. While there are small differences between the effects of spa3 and spa4 mutations, it is apparent that SPA3 and SPA4 function to inhibit light responses in continuous far-red, red, and blue light. Phytochrome A is necessary for all aspects of the spa4 mutant phenotype, suggesting that SPA4, like SPA1, acts specifically in phytochrome A signaling. Enhanced photoresponsiveness of spa3 mutants is also fully dependent on phytochrome A in far-red and blue light, but not in red light. Hence, SPA3 function in red light may be dependent on other phytochromes in addition to phytochrome A. Using yeast two-hybrid and in vitro interaction assays, we further show that SPA3 as well as SPA4 can physically interact with the constitutive repressor of light signaling COP1. Deletion analyses suggest that SPA3 and SPA4, like SPA1, bind to the coiled-coil domain of COP1. Taken together, our results have identified two new loci coding for negative regulators that may be involved in fine tuning of light responses by interacting with COP1.  相似文献   
74.
Oxazolidinone-quinolone hybrids, which combine the pharmacophores of a quinolone and an oxazolidinone, were synthesised and shown to be active against a variety of susceptible and resistant Gram-positive and Gram-negative bacteria. The nature of the spacer greatly influences the antibacterial activity by directing the mode of action, that is quinolone- and/or oxazolidinone-like activity. The best compounds in this series have a balanced dual mode of action and overcome all types of resistance, including resistance to quinolones and linezolid, in clinically relevant Gram-positive pathogens.  相似文献   
75.
The data in this article are based on investigations performed in 25 children with suspected septo-optic dysplasia (SOD). There are many signs and methods that help in the diagnosis of SOD. In particular, the ocular fundus, abnormalities of the hypothalamo-pituitary axis and other midline brain structures should be described. In order to achieve a more holistic and functional diagnosis, the degree of neurological, neuropsychiatric and psychological involvement should also be stated. It has been suggested that SOD is associated with autosomal recessive inheritance, and it can be speculated that it is the result of genetic and environmental influences early in gestation. An early diagnosis can favourably influence the outcome of the affected child.  相似文献   
76.
The Arabidopsis COP1 protein functions as a developmental regulator, in part by repressing photomorphogenesis in darkness. Using complementation of a cop1 loss-of-function allele with transgenes expressing fusions of cop1 mutant proteins and beta-glucuronidase, it was confirmed that COP1 consists of two modules, an amino terminal module conferring a basal function during development and a carboxyl terminal module conferring repression of photomorphogenesis. The amino-terminal zinc-binding domain of COP1 was indispensable for COP1 function. In contrast, the debilitating effects of site-directed mutations in the single nuclear localization signal of COP1 were partially compensated by high-level transgene expression. The carboxyl-terminal module of COP1, though unable to substantially ameliorate a cop1 loss-of-function allele on its own, was sufficient for conferring a light-quality-dependent hyperetiolation phenotype in the presence of wild-type COP1. Moreover, partial COP1 activity could be reconstituted in vivo from two non-covalently linked, complementary polypeptides that represent the two functional modules of COP1. Evidence is presented for efficient association of the two sub-fragments of the split COP1 protein in Arabidopsis and in a yeast two-hybrid assay.  相似文献   
77.
The Nucleolar Localization Elements (NoLEs) of Xenopus laevis U3 small nucleolar RNA (snoRNA) have been defined. Fluorescein-labeled wild-type U3 snoRNA injected into Xenopus oocyte nuclei localized specifically to nucleoli as shown by fluorescence microscopy. Injection of mutated U3 snoRNA revealed that the 5′ region containing Boxes A and A′, known to be important for rRNA processing, is not essential for nucleolar localization. Nucleolar localization of U3 snoRNA was independent of the presence and nature of the 5′ cap and the terminal stem. In contrast, Boxes C and D, common to the Box C/D snoRNA family, are critical elements for U3 localization. Mutation of the hinge region, Box B, or Box C′ led to reduced U3 nucleolar localization. Results of competition experiments suggested that Boxes C and D act in a cooperative manner. It is proposed that Box B facilitates U3 snoRNA nucleolar localization by the primary NoLEs (Boxes C and D), with the hinge region of U3 subsequently base pairing to the external transcribed spacer of pre-rRNA, thus positioning U3 snoRNA for its roles in rRNA processing.  相似文献   
78.
BACKGROUND: Presentation of multiple interactions is of vital importance in the new field of cytomics. Quantitative analysis of multi- and polychromatic stained cells in tissue will serve as a basis for medical diagnosis and prediction of disease in forthcoming years. A major problem associated with huge interdependent data sets is visualization. Therefore, alternative and easy-to-handle strategies for data visualization as well as data meta-evaluation (population analysis, cross-correlation, co-expression analysis) were developed. METHODS: To facilitate human comprehension of complex data, 3D parallel coordinate systems have been developed and used in automated microscopy-based multicolor tissue cytometry (MMTC). Frozen sections of human skin were stained using the combination anti-CD45-PE, anti-CD14-APC, and SytoxGreen as well as the appropriate single and double negative controls. Stained sections were analyzed using automated confocal laser microscopy and semiquantitative MMTC-analysis with TissueQuest 2.0. The 3D parallel coordinate plots are generated from semiquantitative immunofluorescent data of single cells. The 2D and 3D parallel coordinate plots were produced by further processing using the Matlab environment (Mathworks, USA). RESULTS: Current techniques in data visualization primarily utilize scattergrams, where two parameters are plotted against each other on linear or logarithmic scales. However, data evaluation on cartesian x/y-scattergrams is, in general, only of limited value in multiparameter analysis. Dot plots suffer from serious problems, and in particular, do not meet the requirements of polychromatic high-context tissue cytometry of millions of cells. The 3D parallel coordinate plot replaces the vast amount of scattergrams that are usually needed for the cross-correlation analysis. As a result, the scientist is able to perform the data meta-evaluation by using one single plot. On the basis of 2D parallel coordinate systems, a density isosurface is created for representing the event population in an intuitive way. CONCLUSIONS: The proposed method opens new possibilities to represent and explore multidimensional data in the perspective of cytomics and other life sciences, e.g., DNA chip array technology. Current protocols in immunofluorescence permit simultaneous staining of up to 17 markers. Showing the cross-correlation between these markers requires 136 scattergrams, which is a prohibitively high number. The improved data visualization method allows the observation of such complex patterns in only one 3D plot and could take advantage of the latest developments in 3D imaging.  相似文献   
79.
ObjectiveTo describe contraceptive use and attitudes towards contraceptive use in Sweden which has the highest abortion rate in Western Europe. Secondary objectives were to investigate knowledge of contraceptive methods and outcomes of unplanned and unwanted pregnancies.DesignTelephone survey.SettingNational survey of women living in Sweden.PopulationWomen between 16 and 49 years.MethodsThe survey contained 22 questions with free text and multi choice answers on demographics, contraceptive use, knowledge of and attitudes towards contraception, the importance of monthly bleeding and experience of unintended pregnancy.ResultsA total of 1001 women participated in the survey. Of all women, 721/1001 (72.1%) currently used contraception whereas 268/1001 (26.8%) women did not. Long acting reversible contraception, (LARC; implant and intra uterine contraception) was used by 24.3% of women. The unmet need of contraception in Sweden was estimated at 8.9% (89/1001 women). A total of 781 (78%) women had never experienced an unintended pregnancy whereas 220 (22%) women had had at least one unintended pregnancy. Users and non-users alike stated that one of the most important characteristics of a contraceptive method is its effectiveness.ConclusionsSweden has a large unmet need for contraception. Furthermore, a large proportion of women have experienced at least one unintended pregnancy. Increasing contraceptive use and promotion of LARC is a possible way forward in the effort to reduce the rates of unwanted pregnancies.  相似文献   
80.
Several studies demonstrated that visual filtering mechanisms might underlie both conflict resolution of the Flanker conflict and the control of the Garner effect. However, it remains unclear whether the mechanisms involved in the processing of both effects depend on similar filter mechanisms, such that especially the Garner effect is able to modulate filtering needs in the Flanker conflict. In the present experiment twenty-four subjects participated in a combined Garner and Flanker task during two runs of functional magnetic resonance imaging (fMRI) recordings. Behavioral data showed a significant Flanker but no Garner effect. A run-wise analysis, however, revealed a Flanker effect in the Garner filtering condition in the first experimental run, while we found a Flanker effect in the Garner baseline condition in the second experimental run. The fMRI data revealed a fronto-parietal network involved in the processing of both types of effects. Flanker interference was associated with activity in the inferior frontal gyrus, the anterior cingulate cortex, the precuneus as well as the inferior (IPL) and superior parietal lobule (SPL). Garner interference was associated with activation in middle frontal and middle temporal gyrus, the lingual gyrus as well as the IPL and SPL. Interaction analyses between the Garner and the Flanker effect additionally revealed differences between the two experimental runs. In the first experimental run, activity specifically related to the interaction of effects was found in frontal and parietal regions, while in the second run we found activity in the hippocampus, the parahippocampal cortex and the basal ganglia. This shift in activity for the interaction effects might be associated with a task-related learning process to control filtering demands. Especially perceptual learning mechanisms might play a crucial role in the present Flanker and Garner task design and, therefore, increased performance in the second experimental run could be the reason for the lack of behavioral Garner interference on the level of the whole experiment.  相似文献   
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