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71.
Cellular cargoes, including lipid droplets and mitochondria, are transported along microtubules using molecular motors such as kinesins. Many experimental and computational studies focused on cargoes with rigidly attached motors, in contrast to many biological cargoes that have lipid surfaces that may allow surface mobility of motors. We extend a mechanochemical three-dimensional computational model by adding coupled-viscosity effects to compare different motor arrangements and mobilities. We show that organizational changes can optimize for different objectives: Cargoes with clustered motors are transported efficiently but are slow to bind to microtubules, whereas those with motors dispersed rigidly on their surface bind microtubules quickly but are transported inefficiently. Finally, cargoes with freely diffusing motors have both fast binding and efficient transport, although less efficient than clustered motors. These results suggest that experimentally observed changes in motor organization may be a control point for transport.  相似文献   
72.
73.
Molecular Biology Reports - Promoter methylation mediated silencing of tumor suppressor genes plays an important role in the tumorigenesis of colorectal carcinoma (CRC). Tumor suppressor gene,...  相似文献   
74.
In the present investigation, the polysaccharide/mucilage from waste of Abelmoscus esculentus by modification in hot extraction using two different solvents (Acetone, Methanol) were extracted, characterized and further compared with seaweed polysaccharide for their potential applications. The percentage yield, emulsifying capacity and swelling index of this mucilage were determined. The macro algae and okra waste, gave high % yield (22.2% and 8.6% respectively) and good emulsifying capacity (EC% = 52.38% and 54.76% respectively) with acetone, compared to methanol (11.3% and 0.28%; EC% = 50%) (PH = 7) while swelling index was greater with methanol than acetone extracts respectively. The infrared (I.R.) spectrum of the samples was recorded to investigate the chemical structure of mucilage. Thermal analysis of the mucilage was done with TGA (Thermal Gravimetric Analyzer) and DSC (Differential Scanning Calorimeter) which showed both okra and algal polysaccharide were thermostable hydrogels.  相似文献   
75.
Phytochemical investigation of the n-butanol fraction of Evolvulus alsinoides (Linn.) led to the isolation of three new phenolic glycosides, evolvosides C, D and E (13) along with six known compounds (49). The structures of the compounds were elucidated on the basis of spectroscopic analysis, viz. 1D and 2D NMR experiments, chemical study, and comparison with literature data. Evolvoside C (1) was characterized as kaempferol 4′-O-β-d-glucopyranosyl-(1→2)-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside, whereas evolvosides D and E (23) were found to be mono and di-O-methyl derivatives of 1. The new compounds (1–3) represent rare triglycoside derivatives of flavonol at C-4′. The isolated compounds (16) were screened for acute stress-induced biochemical changes in male Sprague–Dawley rats at a dose of 40 mg/kg body weight. Compounds 1 and 2 displayed anti-stress effects by normalizing hyperglycemia, plasma corticosterone, plasma creatine kinase, and adrenal hypertrophy. Compounds 3 and 6 were also found to be effective in normalizing most of these stress parameters, whereas compounds 4 and 5 were ineffective in normalizing most of these effects.  相似文献   
76.
Pandey  Shiv S.  Singh  Sucheta  Babu  C. S. Vivek  Shanker  Karuna  Srivastava  N. K.  Kalra  Alok 《Planta》2016,243(5):1097-1114
Planta - Endophytes reside in different parts of the poppy plant and perform the tissue-specific functions. Most leaf endophytes modulate photosynthetic efficiency, plant growth, and productivity...  相似文献   
77.
Osteoarthritis causes the degradation of the articular cartilage and periarticular bones. Trace elements influence the growth, development and condition of the bone tissue. Changes to the mineral composition of the bone tissue can cause degenerative changes and fractures. The aim of the research was to determine the content of cadmium (Cd), nickel (Ni), copper (Cu) and zinc (Zn) in the tibia, the femur and the meniscus in men and women who underwent a knee replacement surgery. Samples were collected from 50 patients, including 36 women and 14 men. The determination of trace elements content were performed by ICP-AES method, using Varian 710-ES. Average concentration in the tissues of the knee joint teeth amounted for cadmium 0.015, nickel 0.60, copper 0.89 and zinc 80.81 mg/kg wet weight. There were statistically significant differences in the content of cadmium, copper and zinc in different parts of the knee joint. There were no statistically significant differences in the content of cadmium, nickel, copper and zinc in women and men in the examined parts of the knee joint. Among the elements tested, copper and nickel showed a high content in the connective tissue (the meniscus) compared to the bone tissue (the tibia and the femur).  相似文献   
78.
Molecular Biology Reports - TP53 functions primarily as a tumor suppressor, controlling a myriad of signalling pathways that prevent a cell from undergoing malignant transformation. This tumor...  相似文献   
79.
Babu AM  Kumar V  Datta RK 《Mycopathologia》1999,145(1):29-33
Hyphae of Phyllactinia corylea produce two kinds of special branches on the host surface: adhesion bodies which serve as fungal attachment and stomatopodia which enter the leaf through stomata. Conidial germination on host and non-host surfaces was examined with a scanning electron microscope to explain the stimuli responsible for development of the special branches, and the involvement of host recognition in the process. Conidia germinated within 4 h on host and non-host surfaces, but on non-host surfaces the emergence of the germ tube was not always directed towards the substratum. Adhesion bodies were formed from the tips of germ tubes at the first contact point on host and non-host surfaces. Development of stomatopodia was more specific and they were formed precisely over stomata on the host surface. Stomatopodia-like structures were occasionally formed over finely ridged leaf veins on the host surface and over some fine scratches on synthetic surfaces. The experiments showed that while conidial germination and development of adhesion bodies are in response to contact stimuli, the development of stomatopodia is a response to precise topographical signals, and the directional emergence and attached growth of germ tubes involve host recognition.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   
80.
BACKGROUND AND AIMS: All plants synthesize pantothenate but its synthesis and regulation are not well understood. The aim of this work is to study the effect of exogenous supply of precursor compounds on pantothenate levels in leaves. METHODS: Precursor compounds were supplied in solution to excised leaves and the pantothenate content was measured using a microbial method. KEY RESULTS: Pantothenate levels in excised leaves of Limonium latifolium, tomato (Lycopersicon esculentum), bean (Phaseolus vulgaris) and grapefruit (Citrus x paradisi) were examined following an exogenous supply of the precursor compounds pantoyl lactone or beta-alanine. Significantly higher levels of extractable pantothenate were found when pantoyl lactone was supplied, but not when beta-alanine was supplied despite a measurable uptake of beta-alanine into the leaf. CONCLUSIONS: The results suggested that the pantoate supply may be rate-limiting or regulating pantothenate synthesis in leaves.  相似文献   
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