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排序方式: 共有441条查询结果,搜索用时 15 毫秒
1.
Fatma Bouchaala Rabeb Laatar Mariam Lahiani Amira Zouabi Rihab Borji Haithem Rebai 《Chronobiology international》2020,37(2):227-235
ABSTRACTObjective: This study explored the time of day effect of balance performance, functional capacities and risk of fall in three different times in patients with rheumatoid arthritis (RA) and the association between these variations and those of RA symptoms.Methods: A “discontinual” protocol, composed of three test sessions, carried out at 6 am, 2 pm and 10 pm was set up, in order to investigate the time of day effect of balance performance, functional capacities, risk of fall, stiffness, range of motion, swollen and painful joints in women with RA.Results: Time Up and Go Test (TUGT), Functional Reach Test (FRT) and tinetti test scores were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. Stiffness, range of motion, swollen and painful joints values were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. A significant difference was observed on the stiffness, range of motion and swollen joints values between 6 am and 10 pm that were higher at 6 am (p < .05).Using Pearson’s coefficient, correlations were found between RA symptom values; and TUGT, FRT and Tinetti test scores.Conclusion: Results showed a time of day effect of balance performance, functional capacities and risk of falls in women with RA. This variation indicates an alteration of performance at 6 am and 10 pm. Fluctuations of stiffness, limited range of motion, swollen and painful joints noted are concomitant to those of balance performance, functional capacities, and risk of fall.Abbreviations: RA: rheumatoid arthritis; H&O questionnaire: Horne and Ostberg questionnaire; PSQI: Pittsburgh sleep quality index; HAQ: health assessment questionnaire; SF-36: the short form-36; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; TUGT: Time Up and Go Test; FRT: Functional Reach Test 相似文献
2.
Structure of the gene of tum- transplantation antigen P91A: the mutated exon encodes a peptide recognized with Ld by cytolytic T cells 总被引:19,自引:0,他引:19
C Lurquin A Van Pel B Mariamé E De Plaen J P Szikora C Janssens M J Reddehase J Lejeune T Boon 《Cell》1989,58(2):293-303
Mutagen treatment of mouse P815 tumor cells produces immunogenic mutants that express new transplantation antigens (tum- antigens) recognized by cytolytic T cells. We found that the gene conferring expression of tum- antigen P91A contains 12 exons, encoding a 60 kd protein lacking a typical N-terminal signal sequence. The sequence shows no significant similarity with sequences in current data bases. A mutation that causes expression of the antigen is located in exon 4; it is the only apparent difference between the normal and the antigenic alleles. A short synthetic peptide corresponding to a region of exon 4 located around this mutation makes P815 cells sensitive to lysis by anti-P91A cytolytic T cells. The mutation creates a strong aggretope enabling the peptide to bind the H-2 Ld molecule. Several secondary tumor cell variants that no longer express tum- antigen P91A were found to carry deletions in the gene. 相似文献
3.
Interspecific hybridization of cultivated rice, Oryza sativa L. with the wild rice, O. minuta Presl.
A. L. Mariam A. H. Zakri M. C. Mahani M. N. Normah 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(5-6):664-671
Crosses were made between four varieties (Mahsuri, Setanjung, MR84 and MR103) of Oryza sativa L. (2n=24, AA) and one accession of O. minuta (2n= 8, BBCC). The seed set obtained ranged between 9.5% and 25.1% depending on the rice variety used. By rescuing 14-day-old embryos and culturing them on 25%-strength MS medium we obtained a total of 414 F1 hybrids. The F1s were vigorous, tillered profusely, were perennial and male-sterile. The hybrids were triploid (ABC) with 36 chromosomes and showed irregular meiosis. The average frequency and range of chromosome associations at metaphase I or early anaphase I pollen mother cells of F1 plants were 29.31(16–36) Is +3.32(0–10) IIs+0.016(0–1) IIIs+0.002(0–1) IVs. Upon backcrossing the original triploid hybrids and colchicine-treated hybrids to their respective recurrent parents, and further embryo rescue, 17 backcross-1 (BC1) plants were obtained. Of all the crosses using MR84, no BC1 plant was obtained even after pollinating 13 894 spikelets of the triploid hybrid. The BC1s were similar in appearence to the F1s and were male-sterile, their chromosome number ranged from 44 to 48. By backcrossing these BC1s and nurturing them through embryo rescue, we obtained 32 BC2 plants. Of these, however, only 18 plants grew vigorously. One of these plants has 24 chromosomes and the other 17 have chromosome numbers ranging between 30 and 37. The 24-chromosome plant was morphologically similar to the O. sativa parent and was partially fertile with a pollen and spikelet fertility of 58.8% and 12.5% respectively. All of the F1 and BC1 plants were found to be resistant to five Malaysian isolates (XO66, XO99, XO100, XO257 and XO319) of Xanthomonas campestris pv oryzae. Amongst the BC2s, the reaction varied from resistant to moderately susceptible. The 24-chromosome BC2 plant was resistant to the four isolates and moderately resistant to isolate XO100 to which the O. sativa parent was susceptible.Part of PhD thesis submitted by first author to Universiti Kebangsaan Malaysia, Bangi 相似文献
4.
Mariam Lebbadi Antonio Gálvez Eva Valdivia Manuel Martínez-Blueno Mercedes Maqueda 《Archives of microbiology》1994,162(1-2):98-102
Three antibiotic peptides with amoebolytic activity have been purified from culture supernatants of Bacillus licheniformis M-4 (amoebicins m4-A, m4-B, and m4-C). They were hydrophilic peptides consisting of six different amino acids (Asp, Glu, Ser, Thr, Pro, Tyr). Their molecular weights ranged from 3,000 to 3,200. Purified amoebicins were active against human pathogenic and non-pathogenic strains of Naegleria. They also showed a broad antifungal spectrum, but a narrow antibacterial activity.Abbreviations (TFA)
Trifluoroacetic acid 相似文献
5.
Summary A two-step procedure was used for plant regeneration from in vitro grown leaf strips (2–3 mm wide) of cv. Bintje. Step I medium was designed with 2,4-dichlorophenoxycetic acid (2,4-D) at 0.0 or 9.0 M, in combination with 2.28 M kinetin (K), benzyl adenine (BA), zeatin (Z) or zeatin riboside (ZR). Step II media were 2,4-D-free media containing 5.78 M gibberellic acid (GA3) and growth regulators similar to those of step I media. Leaf explants cultured in medium I containing zeatin riboside or zeatin for 6 days and then subcultured in medium II containing zeatin riboside produced numerous shoots without callus formation. Zeatin riboside containing step I and II media caused shoot regeneration in a high number (97.5±2.2) of explants. Approximately, 33.7±8.4 shoots were regenerated from each leaf explant.Abbreviations BA
benzyladenine
- Z
zeatin
- ZR
zeatin riboside (trans isomer)
- 2,4-D
2,4-dichlorophenoxyacetic acid 相似文献
6.
We have established a high-frequency plant regeneration system via somatic embryogenesis from mature seeds of creeping bentgrass (Agrostis palustris Huds). The effects of 2,4-dichlorophenoxyacetic acid (2,4-D), 3.6-dichloroo-anisic acid (dicamba) and 6-benzyladenine (BA) on callus formation and embryogenesis were evaluated. Callus produced on the Murashige and Skoog (MS) (1962) medium containing 2,4-D had low embryogenic potency. In the presence of 30 M dicamba, addition of 2.25 to 9 M BA significantly enhanced embryogenic callus formation over dicamba alone. Optimum frequency of somatic embryogenesis was achieved on MS basal medium containing 30 M dicamba and 2.25 M BA. Over 80% of somatic embryos germinated and formed plantlets on half-strength MS basal medium. These plantlets grew normally in the greenhouse.Abbreviations MS
Murashige and Skoog medium
- 2,4-D
2,4-dichlorophenoxyacetic acid
- BA
6-benzyladenine
- dicamba
3, 6-dichloro-o-anisic acid 相似文献
7.
Paula Ragel Sebastian Streb Regina Feil Mariam Sahrawy Maria Grazia Annunziata John E. Lunn Samuel Zeeman ángel Mérida 《Plant physiology》2013,163(1):75-85
STARCH SYNTHASE4 (SS4) is required for proper starch granule initiation in Arabidopsis (Arabidopsis thaliana), although SS3 can partially replace its function. Unlike other starch-deficient mutants, ss4 and ss3/ss4 mutants grow poorly even under long-day conditions. They have less chlorophyll and carotenoids than the wild type and lower maximal rates of photosynthesis. There is evidence of photooxidative damage of the photosynthetic apparatus in the mutants from chlorophyll a fluorescence parameters and their high levels of malondialdehyde. Metabolite profiling revealed that ss3/ss4 accumulates over 170 times more ADP-glucose (Glc) than wild-type plants. Restricting ADP-Glc synthesis, by introducing mutations in the plastidial phosphoglucomutase (pgm1) or the small subunit of ADP-Glc pyrophosphorylase (aps1), largely restored photosynthetic capacity and growth in pgm1/ss3/ss4 and aps1/ss3/ss4 triple mutants. It is proposed that the accumulation of ADP-Glc in the ss3/ss4 mutant sequesters a large part of the plastidial pools of adenine nucleotides, which limits photophosphorylation, leading to photooxidative stress, causing the chlorotic and stunted growth phenotypes of the plants.The metabolism of starch plays an essential role in the physiology of plants. Starch breakdown provides the plant with carbon skeletons and energy when the photosynthetic machinery is inactive (transitory starch) or in the processes of germination and sprouting (storage starch). Deficiencies in the accumulation of transitory starch in Arabidopsis (Arabidopsis thaliana) have been described previously, specifically in mutants affected in the plastidial phosphoglucomutase (PGM1) or the small subunit (APS1) of the ADP-Glc pyrophosphorylase (AGPase). While they are described as “starchless,” they actually contain small amounts of starch (1%–2% of the wild-type levels; Streb et al., 2009) and share similar phenotypic alterations, such as growth retardation when cultivated under a short-day photoregime and increased levels of soluble sugars during the light phase and reduced levels during the night (Caspar et al., 1985; Lin et al., 1988b; Schulze et al., 1991). Carbon partitioning is altered in these plants. As photosynthate cannot be accumulated as starch, it is diverted via hexose phosphates in the cytosol to the synthesis of Suc, which accumulates together with the hexose sugars, Glc and Fru (Caspar et al., 1985). In Arabidopsis, there are five starch synthase isoforms: one granule-bound starch synthase and four soluble starch synthases: SS1, SS2, SS3, and SS4. We have described previously an Arabidopsis mutant plant lacking SS3 and SS4 that is also severely affected in the accumulation of starch (Szydlowski et al., 2009). SS4 is involved in the initiation of the starch granule and controls the number of granules per chloroplast (Roldán et al., 2007). The elimination of SS3 in an ss4 background leads to an absence of starch in most of the chloroplasts, despite the fact that SS1 and SS2 are still present and total starch synthase activity is only reduced by 35% (Szydlowski et al., 2009). However, a very small proportion of chloroplasts of this mutant plant contain a single huge starch granule, which is also a characteristic of chloroplasts in the ss4 single mutant (D’Hulst and Mérida, 2012). Thus, like aps1 and pgm1, ss3/ss4 plants contain only small amounts of starch. However, unlike aps1 or pgm1 plants, most of the cells of this mutant have empty chloroplasts, without starch (Szydlowski et al., 2009).In this work, we have analyzed the phenotypic effects of the impaired starch accumulation of ss3/ss4 plants. We show that this mutant displays phenotypic changes that are not found in other mutants with very low levels of starch, such as aps1 or pgm1 plants. We provide evidence that extremely high levels of ADP-Glc accumulate in the ss3/ss4 plants. Using reverse genetics to block the pathway of starch synthesis upstream of the starch synthases reduced the level of ADP-Glc in ss3/ss4 plants and reverted the other phenotypic traits. This suggests that ADP-Glc accumulation is the causal factor behind the chlorotic and stunted growth phenotypes of the ss3/ss4 mutant. 相似文献
8.
Energy from biomass plays a large and growing role in the global energy system. Energy from biomass can make significant contributions to reducing carbon emissions, especially from difficult‐to‐decarbonize sectors like aviation, heavy transport, and manufacturing. But land‐intensive bioenergy often entails substantial carbon emissions from land‐use change as well as production, harvesting, and transportation. In addition, land‐intensive bioenergy scales only with the utilization of vast amounts of land, a resource that is fundamentally limited in supply. Because of the land constraint, the intrinsically low yields of energy per unit of land area, and rapid technological progress in competing technologies, land intensive bioenergy makes the most sense as a transitional element of the global energy mix, playing an important role over the next few decades and then fading, probably after mid‐century. Managing an effective trajectory for land‐intensive bioenergy will require an unusual mix of policies and incentives that encourage appropriate utilization in the short term but minimize lock‐in in the longer term. 相似文献
9.
10.
Rafael Deliz-Aguirre Fakun Cao Fenja H.U. Gerpott Nichanok Auevechanichkul Mariam Chupanova YeVin Mun Elke Ziska Marcus J. Taylor 《The Journal of cell biology》2021,220(7)
A recurring feature of innate immune receptor signaling is the self-assembly of signaling proteins into oligomeric complexes. The Myddosome is an oligomeric complex that is required to transmit inflammatory signals from TLR/IL1Rs and consists of MyD88 and IRAK family kinases. However, the molecular basis for how Myddosome proteins self-assemble and regulate intracellular signaling remains poorly understood. Here, we developed a novel assay to analyze the spatiotemporal dynamics of IL1R and Myddosome signaling in live cells. We found that MyD88 oligomerization is inducible and initially reversible. Moreover, the formation of larger, stable oligomers consisting of more than four MyD88s triggers the sequential recruitment of IRAK4 and IRAK1. Notably, genetic knockout of IRAK4 enhanced MyD88 oligomerization, indicating that IRAK4 controls MyD88 oligomer size and growth. MyD88 oligomer size thus functions as a physical threshold to trigger downstream signaling. These results provide a mechanistic basis for how protein oligomerization might function in cell signaling pathways. 相似文献