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111.
Soybean genomic survey: BAC-end sequences near RFLP and SSR markers.   总被引:8,自引:0,他引:8  
We are building a framework physical infrastructure across the soybean genome by using SSR (simple sequence repeat) and RFLP (restriction fragment length polymorphism) markers to identify BACs (bacterial artificial chromosomes) from two soybean BAC libraries. The libraries were prepared from two genotypes, each digested with a different restriction enzyme. The BACs identified by each marker were grouped into contigs. We have obtained BAC- end sequence from BACs within each contig. The sequences were analyzed by the University of Minnesota Center for Computational Genomics and Bioinformatics using BLAST algorithms to search nucleotide and protein databases. The SSR-identified BACs had a higher percentage of significant BLAST hits than did the RFLP-identified BACs. This difference was due to a higher percentage of hits to repetitive-type sequences for the SSR-identified BACs that was offset in part, however, by a somewhat larger proportion of RFLP-identified significant hits with similarity to experimentally defined genes and soybean ESTs (expressed sequence tags). These genes represented a wide range of metabolic functions. In these analyses, only repetitive sequences from SSR-identified contigs appeared to be clustered. The BAC-end sequences also allowed us to identify microsynteny between soybean and the model plants Arabidopsis thaliana and Medicago truncatula. This map-based approach to genome sampling provides a means of assaying soybean genome structure and organization.  相似文献   
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Summary. Spermine is taken up by Ehrlich ascites tumour cells through a specific, saturable, temperature and energy-dependent transport system with a remarkably low affinity constant for spermine (around 1 μM). In the absence of a potassium ion gradient through the plasma membrane, spermine uptake remains saturable but the value of the Km for spermine is much higher (153 μM). Difluormethylornithine treatment (3 mM for 48 h) induces significant increases in Vmax values (up to 9-fold) and changes in the Km values with scarce statistical significance. Among the biogenic amines tested, only spermidine and, partly, agmatine seem to share the same transport system with spermine. No difference is observed in the rate of spermine transport when assays are carried out in the presence of 50-fold excess of ornithine or calcium, or 100-fold excess of glutamine. Received April 25, 2000 Accepted November 1, 2000  相似文献   
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Stress-Management Training for Essential Hypertension: A Controlled Study   总被引:1,自引:0,他引:1  
Forty three patients with essential hypertension participated in a study on the effectiveness of stress-management training for essential hypertension. After 6–9 clinic and 48 self-measured readings of systolic and diastolic blood pressures (SBP and DBP), 22 patients were treated with a program based on education, relaxation, and problem-solving training; and another 21 patients were assigned to a waiting list control group. At post-treatment, mean reductions of clinic BP (17/13 mm Hg vs. 6.9/4.7 mm Hg for SBP/DBP), percentages of subjects who achieved at least a 5 mm Hg reduction (86/86% vs. 48/48% for SBP/DBP) and percentages of subjects who in addition achieved a normotensive level (59/68% vs. 29/14% for SBP/DBP) were significantly higher in the treated group than in the control group. Concerning self-measured BP, the effectiveness of the stress-management training was not so considerable (mean reductions of 3.6/2.4 mm Hg and percentages of subjects who achieved a 5 mm Hg reduction of 52/38% for SBP/DBP), but it was significant and maintained in a 4-month follow-up assessment (mean reductions of 4/2 mm Hg and percentages of subjects who achieved a 5 mm Hg reduction of 48/33% for SBP/DBP). It is suggested that stress-management training can be beneficial for treatment of essential hypertension.  相似文献   
115.
A strain designated as BA03, with the ability to transform ferulic acid into vanillin and 4-vinylguaiacol, was isolated from contaminated cryovials. The production of natural value-added compounds was dependent on the media employed. The morphological and physiological characteristics of this strain were compared with those of the typical vanillin-producer strain Amycolatopsis sp. ATCC 39116. According to a partial 16S rRNA sequence, we determined that BA03 belonged to Bacillus aryabhattai. In addition, analysis of the results showed that this strain exhibited interesting enzymatic activity, including cellulases, laccases, lipases and pectinases. In light of this, we propose new functions for this multitasking microorganism. We suggest that it may be used for converting lignocellulosic wastes into byproducts with industrial uses, and also for treating disposal residues such as dyes in the textile industry. Hence, the possibility for novel research with B. aryabhattai opens up in the fields of biodegradation and/or revalorization of wastes.  相似文献   
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Maternal deprivation (MD) during neonatal life has diverse long-term effects, including modification of metabolism. We have previously reported that MD modifies the metabolic response to high-fat diet (HFD) intake, with this response being different between males and females, while previous studies indicate that in mice with HFD-induced obesity, endocannabinoid (EC) levels are markedly altered in various brown and white adipose tissue depots. Here, we analyzed the effects of MD (24 h at postnatal day 9), alone or in combination with a HFD from weaning until the end of the experiment in Wistar rats of both sexes. Brown and white perirenal and subcutaneous adipose tissues were collected and the levels of anandamide (AEA), 2-arachidonoylglycerol (2-AG), palmitoylethanolamide (PEA), and oleoylethanolamide (OEA) were determined. In males, MD increased the content of OEA in brown and 2-AG in subcutaneous adipose tissues, while in females the content of 2-AG was increased in perirenal fat. Moreover, in females, MD decreased AEA and OEA levels in perirenal and subcutaneous adipose tissues, respectively. HFD decreased the content of 2-AG in brown fat of both sexes and OEA in brown and subcutaneous adipose tissue of control females. In contrast, in subcutaneous fat, HFD increased AEA levels in MD males and OEA levels in control and MD males. The present results show for the first time that MD and HFD induce sex-dependent effects on the main ECs, AEA, and 2-AG, and of AEA-related mediators, OEA and PEA, in the rat brown and white (visceral and subcutaneous) adipose tissues.  相似文献   
118.
During four decades (1960–1990s), the conceptualization and experimental design of studies in kin recognition relied on work with multicellular eukaryotes, particularly Unikonta (including invertebrates and vertebrates) and some Bikonta (including plants). This pioneering research had an animal behavior approach. During the 2000s, work on taxa‐, clone‐ and kin‐discrimination and recognition in protists produced genetic and molecular evidence that unicellular organisms (e.g. Saccharomyces, Dictyostelium, Polysphondylium, Tetrahymena, Entamoeba and Plasmodium) could distinguish between same (self or clone) and different (diverse clones), as well as among conspecifics of close or distant genetic relatedness. Here, we discuss some of the research on the genetics of kin discrimination/recognition and highlight the scientific progress made by switching emphasis from investigating multicellular to unicellular systems (and backwards). We document how studies with protists are helping us to understand the microscopic, cellular origins and evolution of the mechanisms of kin discrimination/recognition and their significance for the advent of multicellularity. We emphasize that because protists are among the most ancient organisms on Earth, belong to multiple taxonomic groups and occupy all environments, they can be central to reexamining traditional hypotheses in the field of kin recognition, reformulating concepts, and generating new knowledge.  相似文献   
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