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1.
The karyotypes of three accessions, one each from three annual species of the genus Cicer, namely Cicer arietinum, Cicer reticulation, and Cicer echinospermum, were examined and compared using C-banding, the fluorochromes chromomycin A3, DAPI, and Hoechst 33258, in situ hybridization of the 18S-5.8S-25S and 5S rDNA sequences, and silver staining. The nuclear DNA content of the three species and the amount of heterochromatin were also determined. The results suggest an evolutionary pathway in which C. reticulatum is the ancestral species from which both C. arietinum and C. echinospermum are derived with the loss of one pair of satellites; subsequently, C. echinospermum further differentiated by the accumulation of chromosomal rearrangement(s) that gave rise to a hybrid sterility barrier. Key words : Cicer, C-banding, fluorochromes, Ag staining, rRNA genes.  相似文献   
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ABSTRACT

We have recently shown that rest-activity circadian rhythm significantly differed in women with Binge Eating Disorder (BED) compared to the Ctrl group. In details, patients with BED exhibited significantly reduced levels of MESOR and Amplitude with respect to the Ctrl group. In addition, in this previous study, the results of the actigraphic sleep monitoring provided no evidence of differences in sleep parameters between the two groups. We expanded the original sample obtaining a total of 28 volunteered women, 14 BED women, and 14 Ctrl. We recorded in all 28 participants a 5-day actigraphic monitoring to detect the rhythmometric parameters, interdaily stability, intradaily variability, L5, M10, and sleep parameters. During the study, BED’s women group kept an individual multidisciplinary therapy lasting five weekly days, from Monday to Friday, consisting in cognitive-behavioral therapy and nutritional program, administered in outpatient care from 8:00 a.m. at 5:00 p.m. The combination of both our previous and current study supports the conclusion that the sleep quality of the BED group is significantly better compared to Ctrl. The non-parametric indexes showed how interdaily stability, significantly correlated to sleep efficiency, was higher in BED group compared to the Ctrl group, indicating a better synchronization of rest-activity circadian rhythm. In conclusion, the maintenance of a regular lifestyle, such as imposed by the multidisciplinary therapy, is important to avoid alterations in the sleep-wake cycle, particularly in patients with eating disorders.  相似文献   
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Journal of Plant Growth Regulation - The potential of microalgae as a biofertilizer in agriculture is increasingly recognized. We studied the effect of applications of Chlorella on growth of wheat...  相似文献   
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Abundant lectin-related proteins found in common beans (Phaseolus vulgaris L.) have been shown to confer resistance against the larvae of a number of bruchid species. Genes encoding for these proteins are members of the lectin multigene family, the most representative components being arcelins, phytohemagglutinins and -amylase inhibitors. Arcelins have been described in seven variants, some of which are resistance factors against the Mexican bean weevil (Zabrotes subfasciatus), a major bean predator. In this study the isolation and sequencing of arcelin genes from wild P. vulgaris genotypes, containing Arc3 and Arc7 variants, is reported, and similarities and evolutionary relationships among the seven known arcelins are described. The evolutionary analysis shows that arcelins 3 and 4 cluster together and are the most-ancient variants. A duplication event gave rise to two additional clusters, one comprising arcelins 1, 2 and 6 and separated from the cluster of arcelins 5 and 7. A multiple number of arcelin genes were found in arcelin 3 and 4 genotypes indicating that more than one type of arcelin gene may be present in the same locus. Some of these sequences are reminiscent of ancient duplication events in arcelin evolution demonstrating that arcelins have evolved through multiple duplications. A further aim of this paper was to better understand and describe the evolution of the entire lectin multigene family. Beside arcelins, a number of other types of sequences, such as putative lectins and sequences not easily classifiable, were found in genotypes containing Arc3 and Arc4. These results, together with the evolutionary analysis, indicate that lectin loci are quite complex and confirm their origin by multiple duplication events.Communicated by J.S. Heslop-HarrisonL. Lioi and F. Sparvoli contributed equally to the work  相似文献   
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Background: Selective cyclooxygenase‐2 (COX‐2) inhibitors and proton pump inhibitors may exert immune‐mediated effects in human gastric mucosa. T‐cell immune response plays a role in Helicobacter pylori‐induced pathogenesis. This study evaluated effects of celecoxib and lansoprazole on T‐helper (Th) 1 and Th2 immune response in human gastric mucosa. Methods: Dyspeptic patients with or without osteoarticular pain were given one of the following 4‐week therapies: celecoxib 200 mg, celecoxib 200 mg plus lansoprazole 30 mg, and lansoprazole 30 mg daily. Expression of COX‐2, T‐bet, and pSTAT6 and production of prostaglandin E2 (PGE2), interferon (IFN)‐γ, and interleukin (IL)‐4 were determined in gastric biopsies before and after therapy. Histology was evaluated. Results: Cyclooxygenase‐2 expression and PGE2 production was higher, and Th1 signaling pathway was predominant in H. pylori‐infected vs. uninfected patients. T‐bet expression and IFN‐γ production increased, while STAT6 activation and IL‐4 production decreased following therapy with celecoxib and celecoxib plus lansoprazole, respectively. Th1 and Th2 signaling pathways down‐regulated after therapy with lansoprazole, and this was associated with an improvement of gastritis. Effect of therapy was not affected by H. pylori status. Conclusion: Celecoxib and lansoprazole modulate Th1/Th2 immune response in human gastric mucosa. The use of these drugs may interfere with long‐term course of gastritis.  相似文献   
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The aims of the present study were to investigate the anticonvulsant activity and behavioral toxicity of FrPbAII using freely moving Wistar rats. Moreover, the effectiveness of this compound against chemical convulsants was compared to that of the inhibitor of the GABAergic uptake, nipecotic acid. Our results show that FrPbAII was effective against seizures induced by the i.c.v. injection of pilocarpine (ED(50) = 0.05 microg/animal), picrotoxin (ED(50) = 0.02 microg/animal), kainic acid (ED(50) = 0.2 microg/animal) and the systemic administration of PTZ (ED(50) = 0.03 microg/animal). The anticonvulsant effect of FrPbAII differed from that of nipecotic acid in potency, as the doses needed to block the seizures were more than 10 folds lower. Toxicity assays revealed that in the rotarod, the toxic dose of the FrPbAII is 1.33 microg/animal, and the therapeutic indexes were calculated for each convulsant. Furthermore, the spontaneous locomotor activity of treated animals was not altered when compared to control animals but differed from the animals treated with nipecotic acid. Still, FrPbAII did not induce changes in any of the behavioral parameters analyzed. Finally, when tested for cognitive impairments in the Morris water maze, the i.c.v. injection of FrPbAII did not alter escape latencies of treated animals. These findings indicate that the novel GABA uptake inhibitor is a potent anticonvulsant with mild side-effects when administered to Wistar rats.  相似文献   
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The lipid profiles of Synechococcus sp. PCC7002 and two related 16S rDNA (99% identity) strains were established by a new method of high-performance liquid chromatography coupled to electrospray-mass spectrometry (HPLC-MS). Lipids were analysed in the positive and negative ionization mode, and fragmentation patterns are reported. No differences in the lipid profile between the three strains could be observed, but the relative content of some species differed. Major lipid species were found to be 1-octadecatrienoyl-2-hexadecanoyl-3-(6'-sulfo-alpha-D-quinovosyl)-sn-glycerol [SQDG (18:3/16:0)] and 1-octadecatrienoyl-2-hexadecenoyl-3-beta-D-monogalactosyl-sn-glycerol [MGDG (18:3/16:1)]. Ten species of SQDG, six species of PG (phosphatidyl-glycerol), seven species of MGDG, and two species of DGDG (digalactosyl-diacyl-glycerol) were detected. A PG species (m/z 761) containing hydroxylinolenic acid or oxophytodienoic acid acyl ester (C18H32O3), and SQDG species containing C17:1 and C17:3 fatty acyl esters are reported for the first time in cyanobacteria. The method also allowed the separation of two pairs of closely related isobaric MGDG species (m/z 770 and m/z 772 in positive ionization).  相似文献   
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Time course of carotenoid and membrane lipid variation during high light (HL) acclimation (about 85 meu mol m-2 s-1), after transfer from low light (LL) (5-10 meu mol m-2 s-1), was determined in a marine Synechococcus strain. Highperformance liquid chromatography (HPLC) coupled to diode array detector (DAD) or electrospray ionization mass spectrometry (ESI-MS) was used for compound separation and detection. Myxoxanthophyll rose within a time interval of 8 h to 24 h after the onset of exposure to HL. Beta -carotene content started to decrease after 4 h of the onset of exposure to HL. Zeaxanthin content rose with exposure to HL, but it was only significant after 24 h of exposure. Carotenoid changes are in agreement with a coordinated activity of the enzymes of the myxoxanthophyll biosynthetic pathway, with no rate-limiting intermediate steps. Lipid analysis showed all species with a C18:3/C16:0 composition increased their content, the changes of PG (18:3/16:0) and MGDG(18:3/16:0) being primarily significant. Major lipid changes were also found to occur within 24 h. These changes might suggest reduction and reorganization of the thylakoid membrane structure. Hypotheses are also drawn on the role played by lipid molecule shape and their possible effect in membrane fluidity and protein accommodation.  相似文献   
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An updated checklist of the vascular flora native to Italy   总被引:1,自引:0,他引:1  
An updated inventory of the native vascular flora of Italy, providing details on the occurrence at regional level, is presented. The checklist includes 8195 taxa (6417 species and 1778 subspecies), distributed in 1092 genera and 152 families; 23 taxa are lycophytes, 108 ferns and fern allies, 30 gymnosperms and 8034 angiosperms. The taxa currently occurring in Italy are 7483, while 568 taxa have not been confirmed in recent times, 99 are doubtfully occurring in the country and 19 are data deficient. Out of the 568 not confirmed taxa, 26 are considered extinct or possibly extinct.  相似文献   
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