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Anterior cruciate ligament injury is a debilitating pathology which may alter lower limb coordination pattern in both intact and affected lower extremities during activities of daily living. Emerging evidence supports the notion that kinematic variables may not be a good indicator to differentiate patients with anterior cruciate ligament deficiency during step descent task. The aim of the present study was to examine alterations in kinematics as well as coordination patterns and coordination variability of both limbs of these patients during a single step descent task. Continuous relative phase technique was used to measure coordination pattern and coordination variability between a group of anterior cruciate ligament deficient (n = 23) and a healthy control group (n = 23). A third order polynomial Curve fitting was utilized to provide a curve that best fitted to the data points of coordination pattern and coordination variability of the healthy control group. This was considered as a reference to compare to that of patient group using nonlinear regression analysis. The results of the present study demonstrated an altered coordination pattern of the supporting shank-thigh and the stepping foot-shank couplings in anterior cruciate ligament deficient subjects. It was further noticed that there was an increased coordination variability in foot-shank and shank-thigh couplings of both supporting and stepping legs. There was no significant difference in the hip, knee and ankle joints kinematics in either side of these patients. Anterior cruciate ligament deficient individuals showed altered strategies in both intact and affected legs, with increased coordination variability. Kinematic data did not indicate any significant difference between the two groups. It could be concluded that more sophisticated dynamic approach such as continuous relative phase would uncover discrepancies between the healthy and anterior cruciate ligament deficient individuals.  相似文献   
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Dental tissue-derived stem cells (DSCs) provide an easy, accessible, relatively noninvasive promising source of adult stem cells (ASCs), which brought encouraging prospective for their clinical applications. DSCs provide a perfect opportunity to apply for a patient's own ASC, which poses a low risk of immune rejection. However, problems associated with the long-term culture of stem cells, including loss of proliferation and differentiation capacities, senescence, genetic instability, and the possibility of microbial contamination, make cell banking necessary. With the rapid development of advanced cryopreservation technology, various international DSC banks have been established for both research and clinical applications around the world. However, few studies have been published that provide step-by-step guidance on DSCs isolation and banking methods. The purpose of this review is to present protocols and technical details for all steps of cryopreserved DSCs, from donor selection, isolation, cryopreservation, to characterization and quality control. Here, the emphasis is on presenting practical principles in accordance with the available valid guidelines.  相似文献   
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"Candidatus Phytoplasma aurantifolia" is the causative agent of witches' broom disease in the Mexican lime tree (Citrus aurantifolia L.), and is responsible for major tree losses in Southern Iran and Oman. The pathogen is strictly biotrophic, and, therefore, completely dependent on living host cells for its survival. The molecular basis of compatibility and disease development in this system is poorly understood. We applied a proteomics approach to analyse gene expression in Mexican limes infected with "Ca. Phytoplasma aurantifolia". Leaf samples were collected from healthy and infected plants and were analysed using 2-DE coupled with MS. Among 800 leaf proteins that were detected reproducibly in eight biological replicates of healthy and eight biological replicates of infected plants, 55 showed a significant response to the disease. MS resulted in identification of 39 regulated proteins, which included proteins that were involved in oxidative stress defence, photosynthesis, metabolism, and the stress response. Our results provide the first proteomic view of the molecular basis of the infection process and identify genes that could help inhibit the effects of the pathogen.  相似文献   
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Length–weight (LWR) and length–length (LLR) relationships were estimated for specimens of two gobiid species collected from the Anzali Wetland and its related streams in the southern Caspian Sea basin, in August 2017. These represent the first reports of LWR and LLR data for Rhinogobius cf. similis Gill, 1859 (37°28′13″N, 49°20′33″E; 50 individuals) and Proterorhinus nasalis (De Filippi, 1863) (36°54′10.89″N, 53°48′48.33″E; 30 individuals) from the Wetland. A new maximum length is reported for P. nasalis. The length–weight parameter b for these species ranged a minimum of 2.99 for Rhinogobius cf. similis to a maximum of 3.04 for P. nasalis with regression coefficients (r2) ranging from .95 to .97. All LLRs were highly significant (r2>.96).  相似文献   
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Salvia is the most species-rich genus in Lamiaceae, encompassing approximately 1000 species distributed all over the world. We sought a new evolutionary perspective for Salvia by employing macroevolutionary analyses to address the tempo and mode of diversification. To study the association of floral traits with speciation and extinction, we modelled and explored the evolution of corolla length and the lever-mechanism pollination system across our Salvia phylogeny. We reconstructed a multigene phylogeny for 366 species of Salvia in the broad sense including all major recognized lineages and 50 species from Iran, a region previously overlooked in studies of the genus. Our comprehensive sampling of Iranian species of Salvia provides higher phylogenetic resolution for southwestern Asian species than obtained in previous studies. Our phylogenetic data in combination with divergence time estimates were used to examine the evolution of corolla length, woody versus herbaceous habit, and presence versus absence of a lever mechanism. We investigated the timing and dependence of Salvia diversification related to corolla length evolution through a disparity test and BAMM analysis. A HiSSE model was used to evaluate the dependency of diversification on the lever-mechanism pollination system in Salvia. A medium corolla length (15–18 mm) was reconstructed as the ancestral state for Salvia with multiple shifts to shorter and longer corollas. Macroevolutionary model analyses indicate that corolla length disparity is high throughout Salvia evolution, significantly different from expectations under a Brownian motion model during the last 28 million years of evolution. Our analyses show evidence of a higher diversification rate of corolla length for some Andean species of Salvia compared to other members of the genus. Based on our tests of diversification models, we reject the hypothesis of a direct effect of the lever mechanism on Salvia diversification. Therefore, we suggest caution in considering the lever-mechanism pollination system as one of the main drivers of speciation in Salvia.  相似文献   
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An in vitro cell suspension culture of Echium italicum was established and assayed for the production of shikonin and alkannin derivatives. Callus tissues were induced from cotyledon explants of the plant incubated onto the solidified B5 medium. A two-liquid-phase system suspension culture was then established to elicit pigments of shikonin and alkannin derivatives using liquid paraffin. The presence of liquid paraffin efficiently induced production of pigments in cultured cells. The production and/or accumulation of these compounds in the E. italicum cells was examined using fluorescence microscopy as the naphthoquinone molecules display autofluorescent properties. Phytochemical analysis of the n-hexane extract of the medium was also carried out using preparative HPLC. The chemical structure of shikonin and alkannin derivatives were characterized by UV, 1H-NMR, and 13C-NMR techniques. Based on our findings, this bioprocess engineering approach resulted in induction of shikonin and alkannin derivatives, whereupon it may be recruited for production of these important secondary metabolites.  相似文献   
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Journal of Plant Growth Regulation - Activation of complex metabolic pathways and antioxidant activities is necessary for enhancing quality and health promoting capacity of food crops. Plant growth...  相似文献   
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