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591.
Occlusal changes were important factors in temporomandibular disorder (TMD). It is of interest to evaluate the association of occlusal wear facets in TMD patients. We used a dataset of 49 patients with and without TMD for this study. Occlusal wear facets were evaluated using Smith and Knight tooth wear index. Data shows that teeth wear was present more in patients with TMD (55%). The age group 26-40 years showed high prevalence of teeth wear (grade1) in TMD patients (P value = 0.034). TMD was present more in females than males. Female (54%) patients with TMD showed more teeth wear compared to males. Most patients with TMD showed posterior teeth wear (61%) than generalized teeth wear. Thus, association was present between occlusal teeth wear and TMD patients especially in the age group of 26-40 years. Hence, proper evaluation of occlusal factors will aid in early diagnosis of TMDs.  相似文献   
592.
Video-on-demand (VOD) servers need to be efficiently designed in order to support a large number of users viewing the same or different videos at different rates. While considering a disk-array based VOD server, use of a shared buffer at the server end may be more economical than the sole use of dedicated buffers at each user's end. In this paper, we propose a simple buffer sharing architecture that may be used when disk-array based video servers are used. Our aim is to support the maximum number of users for a given number of video server disks while employing a simple scheme requiring less buffer space. The number of video segment retrievals that can occur within a certain time (the service round) is maximum when the scan disk scheduling algorithm is used. Consequently, we shall assume use of the scan algorithm for disk retrieval. The VOD server has a buffer manager that directs retrieved segments to appropriate buffer locations depending on their release and deadlines. The release and deadlines of segments are such that buffer requirement at the user's set-top box is minimized to two video segments while avoiding video starvation and buffer overflow at the user's end. We propose a novel scheme for the operation of the shared buffer that aims at increasing buffer utilization and decreasing cell loss due to buffer overflow. An ATM based broadband network is assumed and all segments are stored in buffers as fixed length ATM cells. We also use a novel scheme for grouping frames into segments and illustrate its advantages over earlier ones. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
593.
As the use of various anticancer drugs is associated with many undesirable side effects, there is an urgent need for the discovery of new, better, and specific anticancer compounds. Antioxidant and antiproliferative activities as well as effects on cell morphology were investigated for methanol (M), chloroform (C), ethyl acetate (E), and aqueous (A) extracts of Caulerpa peltata, Gelidiella acerosa, Padina gymnospora, and Sargassum wightii using 2,2-diphenyl-1-picrylhydrazyl radical-scavenging, ferrous ion chelation, and resazurin-based growth inhibition (in A549, HCT-15, MG-63, and PC-3 cell lines) assays. A general trend was the greater extraction of phenols and flavonoids by chloroform and ethyl acetate, which showed higher activity in many assays. These non-polar C and E extracts showed higher DPPH radical-scavenging and growth inhibitory activities in A549, HCT-15, and PC-3 cells. However, higher ferrous ion chelation (A extracts) and growth inhibition in MG-63 cells (M and A extracts) were seen for the polar extracts. Furthermore, P. gymnospora and C. peltata emerged as promising sources for antiproliferative agents that could be explored for their own activity and as leads for the development of other compounds.  相似文献   
594.
Aims: To isolate and identify the bioactive compounds produced by Nocardia levis MK‐VL_113. Methods and Results: Cultural characteristics of Noc. levis isolated from laterite soils of Guntur region were recorded on International Streptomyces Project media. Morphological studies of the strain through scanning electron microscopy revealed the clear pattern of its hyphal fragmentation into rod‐shaped bacilli. Chemical examination of the secondary metabolites of the strain grown on sucrose–tryptone broth led to the isolation of three fractions active against Bacillus cereus. Further analysis of second fraction resulted in the isolation of two active subfractions. Two different phthalate esters, namely, bis‐(2‐ethylhexyl) phthalate and bis‐(5‐ethylheptyl) phthalate, were purified from the first active subfraction, and the structural elucidation of these compounds was confirmed on the basis of FT‐IR, mass and NMR spectroscopy. The partially purified second subfraction subjected to Gas Chromatography–Mass spectroscopy contained nine components: decanedioic acid; 2,6‐piperdione monooxime; 1‐eicosanol; beta‐1‐arabinopyranoside, methyl; cyclopentaneundecanoic acid; hexadecanoic acid; silane, trichloro eicosyl; 1‐hexacosanol; and 1,2‐dodecanediol. The antimicrobial activity of the bioactive compounds produced by Noclevis was expressed in terms of minimum inhibitory concentration. Conclusions: The present study clearly revealed that the metabolites of Noc. levis act as bioactive compounds against Gram‐positive and Gram‐negative bacteria, yeast and filamentous fungi. It also supports the idea that there are a number of rare actinomycetes remained to be explored for new bioactive compounds. Significance and Impact of the Study: Metabolites of Noc. levis exhibited antibacterial and antifungal activities. This is the first report of bis‐(5‐ethylheptyl) phthalate as well as the nine partially purified compounds from actinomycetes. In addition, this is also the first report of bis‐(2‐ethylhexyl) phthalate from the genus Nocardia.  相似文献   
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598.
Diabetic retinopathy (DR) is the leading cause of visual impairment in adults of working age (20–65 years) in developed countries. The metabolic memory phenomena (persistent effect of a glycemic insult even after retrieved) associated with it has increased the risk of developing the complication even after the termination of the glycemic insult. Hence, the need for finding early diagnosis and treatment options has been of great concern. Epigenetic modifications which generally occur during the beginning stages of the disease are responsible for the metabolic memory effect. Therefore, the therapy based on the reversal of the associated epigenetic mechanism can bring new insight in the area of early diagnosis and treatment mechanism. This review discusses the diabetic retinopathy, its pathogenesis, current treatment options, need of finding novel treatment options, and different epigenetic alterations associated with DR. However, the main focus is emphasized on various epigenetic modifications particularly DNA methylation which are responsible for the initiation and progression of diabetic retinopathy and the use of different epigenetic inhibitors as a novel therapeutic option for DR.  相似文献   
599.
Mangiferin, a polyphenol compound of C-glucoside, is well-known for its anti-inflammatory, antioxidant, anticancer, antidiabetic and cognitive enhancement properties. In this study, we investigated the neuroprotective effect of mangiferin against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of Parkinson’s disease (PD), which is most popular and widely used to evaluate therapeutic implications of new protective agents. Male C57BL/6 mice were orally treated with mangiferin (10, 20 and 40 mg/kg body wt.) for 14 days and from 10th day onwards MPTP (30 mg/kg, i.p.) was injected for last 5 days. MPTP treatment leads to enhanced oxidative stress, induction of apoptosis (upregulates the expression of Bax, proapoptotic protein and downregulates the expression of anti-apoptotic marker Bcl-2), and loss of dopominergic neurons which results in motor impairments. Results of our study confirmed that mangiferin prevented MPTP-induced behavioral deficits, oxidative stress, apoptosis, dopaminergic neuronal degeneration and dopamine depletion. Taken together, we conclude that mangiferin attenuates the dopaminergic neurodegeneration mainly through its potent antioxidant and antiapoptotic properties.  相似文献   
600.
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