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21.
目的:研究氧化锆全瓷和金属烤瓷冠修复对牙冠延长术后牙周状况的影响,为临床治疗提供依据。方法:选取2014年12月到2015年2月我院收治牙冠延长术联合牙冠修复治疗患者210例,按照随机数字表法将患者分为研究组和对照组,每组105例,研究组应用氧化锆全瓷,对照组应用金属烤瓷,比较两组牙周情况、佩戴修复体时间和康复时间。结果:研究组正常者比例为83.81%(88/105)显著高于对照组的65.71%(69/105),轻度病损者比例为8.57%(9/105)显著低于对照的21.90%(23/105),比较差异具有统计学意义(P0.05);研究组术后佩戴修复体时间和康复时间均显著短于对照组,比较差异具有统计学意义(P0.05)。结论:应用氧化锆全瓷修复能改善牙冠延长术后患者牙周情况,缩短佩戴修复体时间和康复时间。  相似文献   
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The efficiency of an intercropping system depends mainly on the cropping system and on the crops, which should complement each other. However, the choice of crops and factors of production are extremely important for maximizing the advantages of intercropping, which, in turn, means maximizing the bio-agro-economic performance of the system. The present study sought to assess, based on appropriate indexes and indicators and using univariate and bivariate analysis, the agronomic/biological and economic returns from a system in which salad rocket was intercropped with carrot at different population densities and one of spontaneous species of the semi-arid region of Brazil, namely hairy woodrose (Merremia aegyptia L.), was used as green manure. The population densities of both the crops were maintained at 40%, 60%, 80%, or 100% of the recommended population for a sole crop (RPSC). The following values were recorded or calculated: green biomass of rocket, biomass of carrot roots, aggressivity indexes, competitive ratio, land equivalent ratio, productive efficiency index, canonical variable score, and four economic indicators, namely gross and net returns, rate of return, and net profit margin. The most effective combination was carrot at 40% of its RPSC intercropped with rocket at 100% of its RPSC with hairy woodrose as green manure because the combination resulted in the highest values of land equivalent ratio (1.72), productive efficiency index (0.91), canonical variable score (1.68), gross returns (R$ 41,186.91 ha−1), net returns (R$ 18,621.64 ha−1), rate of return (1.84), and net profit margin (52.77%), making it a highly profitable combination for the north-eastern semi-arid region of Brazil. The most effective indicators of economic value were yield and the rate of return.  相似文献   
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ObjectiveStudy the effect of electroacupuncture on permenopausal depressive disorder (PDD) model through the peri-menopausal depression model mice.MethodsKM female mice were selected. Except for the blank group (BG), the other groups of mice were removed by castration method. The mice of PDD was prepared by combining chronic unpredictable stimulation. Mice in the model group (MG) were not treated and fed normally. The western medicine group (WG) was given the corresponding drug for treatment. The electroacupuncture group (EAG) was given the electroacupuncture for treatment, and consecutive for 28 days. The levels of T, E2, FSH and LH in serum of mice were measured, and the brain tissue of 5-HT, DA and NE level were measured. Through the HE staining observed the morphological changes of mice hypothalamus.ResultsCompared with MG, EAG could increase the number of spontaneous activities of PDD model mice, the level of T, E2 in serum and the level of 5-HT, DA, NE in brain tissue was improved, and the level of FSH, LH in serum was reduced, and the hypothalamic lesions was improved.ConclusionElectroacupuncture could improve the activity and memory of PDD mice, adjust the disorder of sex hormone, and increased the levels of monoamine transmitters (5-HT, NE, DA), and it could effectively improve the behavior and related biochemical indexes of PDD, and thus play an important therapeutic role.  相似文献   
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The issue of amino acid depth in proteins gives important insights to our understanding of protein’s three-dimensional structure. There has already been much research done in mathematical and statistical sciences regarding the general definitions, properties and algorithms describing the particle depth of spatially extended systems. We constructed a method of calculating the amino acids depths and applied it to a set of 527 protein structures. We propose the introduction of amino acid depth tendency factors for three-dimensional structures of proteins. The depth tendency factors relate not only to the hydrophobicity indices but also to the electrostatic charge. We found a relationship between the protein size and the number of residues using the distance between the deepest residue and surface residues. We made a prediction regarding the number of residues on the surface of a protein, the deepest amino acid, and the average depth, all of which are fitted well to a linear functional relationship with the length of the protein. Finally, we have predicted the depths of multiple peptides in protein’s three-dimension structure. Electronic supplementary material The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   
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This study investigated the age-dependent changes in the number of BrdU- and TUNEL-positive cells in murine gingival tissue and submandibular gland, and compared the findings with those in other tissues and organs. The cell proliferative activity was decreased after 20 weeks of age in epithelial cells of the gingiva, tongue, buccal mucosa and skin. A decreased cell proliferative activity was also associated with aging in the liver and kidney parenchymal cells. Meanwhile, cell death showed peculiar changes in gingival subepithelial tissue, and mucous and serous acini of the submandibular gland. An increase of TUNEL-positive cells was demonstrated in gingival subepithelial tissue after 20-week-old of age. A significant increase of TUNEL-positive cells was also found in the mucous acinar cells in the 20-week-old mice and in the serous acini after 20 weeks. The fluctuation in the number of TUNEL-positive cells in the subepithelial tissue of the skin, and BrdU- and TUNEL-positive staining ratios in the liver was smaller than that in other tissue and organs throughout life. This study may provide useful information for better understanding the influence of aging on the functional alteration that occurs in the gingival tissue and submandibular gland of the elderly.  相似文献   
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In the inflammatory gingival tissues of patients with periodontitis, cytokines such as interleukin (IL)-1 alpha, IL-1 beta, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha have been detected. Gingival fibroblasts are the major constituents of gingival tissue. We recently demonstrated that lipopolysaccharide (LPS) from periodontopathic bacteria induces inflammatory reactions in various tissues via CD14 and/or Toll-like receptors (TLRs) in gingival tissues [Biochem. Biophys. Res. Commun. 273 (2000) 1161]. To confirm this, we examined the expression of IL-1 alpha, IL-1 beta, IL-6, IL-8, TNF-alpha, CD14, TLR2, and TLR4 in human gingival fibroblasts (HGFs) obtained from patients with healthy or inflammatory gingiva using DNA microarray analysis. We also studied the expression levels of these proteins by flow cytometric analysis (FACS). The expression levels of all eight genes in the HGFs of the Inflammatory group were significantly higher than those in the Healthy group on DNA microarray analysis. FACS revealed that the expression levels of all eight proteins on the HGFs of the Inflammatory group were higher than those on the Healthy group. Our data indicated that these eight proteins in HGFs are involved in inflammatory conditions in the gingiva, including periodontal disease. Our results suggested that these eight proteins, in turn, act directly or indirectly on the immune response by activating host cells involved in inflammatory processes.  相似文献   
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Pérez Latorre  A.V.  Cabezudo  B. 《Plant Ecology》2002,161(2):231-249
The ecomorphological and phenological study was carried out within aMediterranean vegetation context, in Quercus suberforests,which have been substituted by shrublands of Cistus sppwithin two Natural Parks in the south of the Iberian Peninsula. Theecomorphological characters that show meaningful differences between both typesof vegetation are: location of renewal buds, spinescence, stratification,maximum height of the vegetation, organs periodically shed, leaf consistency,leaf tomentosity, leaf size, and life duration of leaves, plant duration,vegetative regeneration after fire, main vegetative growth season, mainflowering season and fruit type. The phenological phases also help to discernbetween forest and shrubland, specially flower bud formation, fruiting, seeddispersal, and the existence of brachyblast vegetative growth and brachyblastleaf shedding. We propose three new indexes based on phenological phases:active period of the species (APS), active period of thecommunity (APC) and reproductive/vegetative activity of thespecies (RVA). The results of their application, in combination with theecomorphological characters, have proved promising in describing vegetation andin clearly differentiating communities. The results also show the existence ofdifferent ecomorphological groups of plants at community level, with consequentecological, historical, phytocoenological and adaptive implications  相似文献   
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A method for isolation of rat hepatocytes using liver perfusion by ethylenediamine tetra-acetic acid (EDTA)-containing sucrose solution and mechanical tissue disaggregation by controlled vibration (MVD) is described. The yields of hepatocytes produced by this method were similar to those obtained using collagenase perfusion. The cells had well preserved membrane integrity as judged by the trypan blue staining test (91 +/- 4%), ATP contents, rates of endogenous respiration and enzyme leakage that indicated they were functional cells. There was little evidence of expression of latent damage when the cells were stored either at 37 degrees C (by pre-incubation) or at 4 degrees C. This method can be used to isolate high yields of functional cells from rat liver if the collagenase perfusion technique is not available.  相似文献   
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