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41.
Tingting Zheng Lulu Liu Jiayi Liu Zhengxiang Zhang 《Journal of musculoskeletal & neuronal interactions》2022,22(2):296
There are few reports of rhabdomyolysis caused by anticoagulants, and it is extremely rare for it to be caused by dabigatran etexilate. An 86-year-old female experienced sudden muscle weakness and pain, a significant increase in Creatine kinase, and renal impairment after oral administration of dabigatran etexilate for 3 weeks. The enhanced thigh MRI showed abnormal signal in multiple thigh muscle groups, indicating that the lesions should be considered inflammatory diseases. In conclusion, the possibility of rhabdomyolysis should be ruled out when muscle weakness and myalgia occur at the beginning of dabigatran etexilate treatment. 相似文献
42.
The biochemical mechanisms underlying thidiazuron (TDZ)-induced regeneration in plant cells have not been clearly elucidated.
Exposure of leaf explants of Echinacea purpurea to a medium containing TDZ results in undifferentiated cell proliferation and differentiated growth as mixed shoot organogenesis
and somatic embryogenesis. The current studies were undertaken to determine the potential roles of auxin, indoleamines, and
ion signaling in the dedifferentiation and redifferentiation of plant cells. E. purpurea leaf explants were found to contain auxin and the related indoleamine neurotransmitters, melatonin, and serotonin. The levels
of these endogenous indoleamines were increased by exposure to TDZ associated with the induction of regeneration. The auxin-transport
inhibitor 2,3,5-triiodobenzoic acid and auxin action inhibitor, p-chlorophenoxyisobutyric acid decreased the TDZ-induced regeneration but increased concentrations of endogenous serotonin
and melatonin. As well, inhibitors of calcium and sodium transport significantly reduced TDZ-induced morphogenesis while increasing
endogenous indoleamine content. These data indicate that TDZ-induced regeneration is the manifestation of a metabolic cascade
that includes an initial signaling event, accumulation, and transport of endogenous plant signals such as auxin and melatonin,
a system of secondary messengers, and a concurrent stress response. 相似文献
43.
44.
It was well known that beta-amyloid (Abeta) and tau protein play an important role in pathological procedure of Alzheimer's disease (AD), a senile dementia. The growth inhibitory factor (GIF, also named metallothionein-3, MT-3) had been demonstrated to inhibit the outgrowth of cortex neurons in the medium with extract of the AD patient brain. In our experiments, it was found that the neurons of cortex and the PC12 (pheochromocytoma) cells could be protected from the cytotoxicity of beta-amyloid 25-35 in presence of GIF and its domains. Additionally, GIF can scavenge the hydroxyl radical efficiently in CytC-VitC radical producing system and its alpha-domain shown more effective potentials than its beta-domain. The electron paramagnetic resonance spectra also show that the alpha-domain has more potential ability for eliminating reactive oxygen free radicals than its beta-domain. The results suggest that GIF could act as an efficient scavenger against free radicals in vitro and the alpha-domain in GIF molecule shows more potential in protecting against reactive oxygen species injury than the beta-domain. 相似文献
45.
46.
Abstract In this paper, two new species of the genus Phytocoris Fallen ( Ph. nitrariae sp. nov., Ph. macer sp. nov.) are described from China. Both of these two species belong to the subgenus Sooso-capsus Wagner when Wagner's system (1970) is used. 相似文献
47.
Nadiah Pardede Kristensen Jacob Johansson Niclas Jonzén Henrik G. Smith 《Evolutionary ecology》2018,32(5):509-528
It is generally expected that, in environments with pronounced seasonal resource peaks, birds’ reproductive success will be maximised when nestlings’ peak food demand coincides with the timing of high food availability. However in certain birds that stay resident over winter, earlier breeding leads juveniles to join the winter flock earlier, which by the prior residence effect increases their success in breeding territory competition. This trade-off between reproduction and competition may explain why, in certain species, breeding phenology is earlier and asynchronous with the resource. This study extends a previous model of the evolution of breeding phenology in a single habitat type to a landscape with two habitat types: ‘early’ and ‘late’ resource phenology. The offspring’s natal habitat type has a carryover effect upon their competitive ability regardless of which habitat type they settle in to potentially breed. We find that, when the difference in resource phenology between habitats is small (weak carryover effect), breeding phenology in the late habitat evolves to occur earlier and more asynchronously than in the early habitat, to compensate for the competitive disadvantage to juveniles raised there. However if the difference is large (strong carryover effect), then the reproductive cost of earlier breeding outweighs the benefit of the compensation, so instead breeding phenology in the late habitat evolves to become more synchronous with the resource. Recruitment is generally asymmetric, from early to late habitat type. However if the early habitat is less frequent in the landscape or produces fewer offspring, then the asymmetry is reduced, and if there is some natal habitat-type fidelity, then recruitment can have an insular pattern, i.e. most recruits to each habitat type come from that same habitat type. We detail the different scenarios in which the different recruitment patterns are predicted, and we propose that they have implications for local adaptation. 相似文献
48.
Kuvalekar Aniket Pawar Pankaj Khare Ankita Gandhe Kanchanganga Harsulkar Abhay 《Plant Cell, Tissue and Organ Culture》2008,94(1):101-104
Ravenelia esculenta Naras. and Thirum. is a rust, pathogenic to Acacia eburnea Willd. The infection leads to hypertrophy changing the morphology with bizarre shapes of plant organs. Healthy and infected
tissues were subjected to extraction of IAA and indole derivatives and were estimated by spectrophotometric methods. The hypertrophy
produced was presumed to be due to increase in the indole-3-acetic acid (IAA) content in the infected tissue, however, the
amount of IAA in infected tissues decreased with the progression of disease. Concomitantly, the infected tissue showed the
presence of a novel, slow migrating, indole derivative on TLC. Cultured shoot tips of Withania somnifera were dosed with the methanolic extract of the infected hypertrophied tissue (MEHT) (0.25, 0.5, 0.75, 1.00 and 1.25 mg/l).
The stimulation in shoot growth along with profuse rooting was observed in a dose dependent manner with maximum at 1.00 and
1.25 mg/l concentration. 相似文献
49.
Sporopollenin layers in the cell wall of coccal green algae are responsible for the resistance of cell walls to destructive processes during fossilization as well as during chemical preparation of samples for pollen-analysis. Pollen slides of samples from limnic sediments thus also contain some algal cell walls. Although some pollen-analysts tried to stress this fact, the finds of algae in pollen slides have not been paid systematic attention yet, despite their potential use for a more accurate palaeoecological reconstruction. The article summarizes the results of palaeoecological studies showing how the algae can be used in palaeoecological reconstruction of past environments. The possibility of utilizing the indicative value of algal finds is demonstrated on examples of algal communities from fossil, subrecent and recent sediments from different longitudes, latitudes, and altitudes. The identification and indicative values of species and varieties ofPediastrum are included in a special review (Komárek &; Jankovská, Biblioth. Phycol., in press). The contemporary knowledge of ecological requirements of the given taxa, completed by information from their fossil finds, makes possible the reconstruction of trophic and temperature conditions and of the purity of the water environment of the past water biotopes. 相似文献
50.
Spatio-temporal tumour model for analysis and mechanism of action of intracellular drug accumulation
We have developed a one-dimensional tumour simulator to describe the biodistribution of chemotherapeutic drugs to a tumoral
lesion and the tumour cell’s response to therapy. A three-compartment model is used for drug dynamics within the tumour. The
first compartment represents the extracellular space in which cells move, the second corresponds to the intracellular fluid
space (including cell membrane) which is in direct equilibrium with the extracellular space, and the third is a non-exchangeable
compartment that represents sequestered drug which is trapped in the nucleus to damage the cellular DNA, directly triggering
cell death. Analytical and numerical techniques (Finite Element Method) are used to describe the tumour’s response to therapy
and the effect of parameter variation on the drug concentration profiles in the three compartments. 相似文献