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1.
AIM: To examine the expression and distribution of tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor I (TNFR I) and apoptosis in oral lichen planus, and evaluate their roles and relation in the oral lichen. METHODS: Immunohistochemical technique and TUNEL were employed to study the expression of TNF-α, TNFR I and apoptosis in 50 cases of oral lichen planus and 10 normal oral mucosa specimens. RESULTS: Compared with the normal control group, TNF-α expression was upregulated in mononuclear cells in lamina propria and decreased in keratinocytes in oral lichen planus lesion (P<0.05). On the contrary, TNFR I expression was increased in keratinocytes and decreased in lamina propria in oral lichen planus lesion (P<0.05). The increased apoptosis index in keratinocytes and the decreased apoptosis index in lamina propria were found in oral lichen planus (P<0.05). CONCLUSION: The accelerated apoptosis of keratinocytes and the inhibition of lymphocytes apoptosis may contribute to the formation and progression of oral lichen planus.  相似文献   
2.
This study was carried out to determine the effect of water stress on five different generative stages of soybeans and to evaluate the CROPGRO-soybean model under semi-arid climatic conditions. The study was conducted at the Faculty of Agricultural Engineering, Harran University research field in 2003 and 2004 growing seasons. Plants received full irrigation during vegetative stages, after which it was cut off at different reproductive stages (treatments): R1-2, beginning of flowering and full bloom; R3, beginning of pod; R4, full pod; R5, beginning of seed; and R6, full seed. The control treatment was full irrigation throughout. Observed yields ranged from 1955 (R6) to 3684 kg ha−1 (control) in 2003, and from 1867 (R6) to 3952 kg ha−1 (control) in 2004, respectively. Generally, in both of the years any water stress imposed on soybeans in three different generative stages (R3, R5, and R6) resulted in substantial yield reduction compared with full irrigation; yield reduction was greatest at the R6 stage. Biomass and 1000 seed weight also showed significant difference. Overall, CROPGRO-soybean simulated parameters from all treatments were higher compared with observed ones. Although simulated yield results were close to measured ones, they could not track observed yield patterns. Generally, the CROPGRO-soybean simulation model failed to satisfactorily mimic observed soybean yield, biomass, and 1000 seed weight and therefore it is suggested not to be used for similar scenarios and climatic conditions.  相似文献   
3.
The effects of dimethoate on hematological, biochemical parameters, and behavior were investigated in Oncorhynchus mykiss exposed to sublethal concentrations of 0.0735, 0.3675, and 0.7350 mg/l for 5, 15, and 30 days. Significant decrease was determined in erythrocyte and leukocyte counts, hemoglobin, hematocrit, MCV, and MCH, which was pronounced after prolonged exposure indicating the appearance of microcytic hypochromic anemia. There were no prominent changes in thrombocyte and MCHC. The glucose concentration showed an ascending pattern that proved to be positively correlated with duration. The protein concentration declined in higher dimethoate concentrations following 15 and 30 days. Negative and significant correlation was detected between glucose and protein concentrations. The fish showed remarkable behavioral abnormality such as loss of balance, erratic swimming, and convulsion. Present findings revealed that dimethoate exerts its toxic action even in sublethal concentrations and hematological parameters and abnormal behavior may be sensitive indicators to evaluate pesticide intoxication.  相似文献   
4.
This paper focuses on understanding the role of structural parameters and starch crystallization on the toughness of cake samples. Accurate mechanical measurements were performed to obtain toughness values, and these were related to structural parameters obtained from image analyses. Three-dimensional skeletons of food samples were generated by using X-ray tomography technique. The structural parameters (cell diameter, cell wall thickness, thickness to radius ratio (t/R), fragmentation index) were obtained after processing of the images with CTan software. The basic hypothesis of the paper is to show that the structural parameter t/R is a determinant for predicting toughness, which is a critical indicator of freshness. Freshness in cakes and other baked products is a leading factor in consumer perception. For this purpose three different cake formulations were stored at 37 and 50 °C. Cycling from these temperatures to lower storage temperatures of 25 and 4 °C was done to accelerate the starch retrogradation rate. Experimental results indicated that there was a strong interrelationship between morphological structure and the mechanical properties with regression coefficients of 0.68 and 0.95. Starch retrogradation, which was followed by X-ray diffractometry, was found to be directly proportional to toughness values, where the percent relative crystallinity increased with storage temperature.  相似文献   
5.
In order to explore an alternative method instead of plasticization for improving the toughness, flexibility and processability of PLA based packaging films, two different kinds of modified polyethylene based elastomers, such as glycidyl methacrylate or maleic anhydride functionalized ethylene-acrylate based elastomers, were melt blended with PLA. Their properties were compared with conventional PEG plasticized PLA. The chemical interaction between end groups of PLA and epoxide or maleic anhydride functional groups of elastomers was shown by FTIR. Scanning electron microscopy showed that up to 20 % PEG loading, one phase morphology was achieved, however beyond this point, a phase separation was observed for plasticized PLA. For PLA/elastomer blends, a two-phase morphology was obtained as a result of immiscible nature of PLA and elastomers. Tensile and dynamic mechanical properties indicated that elastomer based blends were better than plasticized PLA independently from elastomer type. Differential scanning calorimeter (DSC) analysis exhibited that the T g value was remarkably lowered in the plasticized PLA; however, it did not change in the case of elastomers. In terms of oxygen permeability and biodegradability, plasticized PLA was found to be better than elastomer based blends.  相似文献   
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通过探讨柞蚕(Antheraea pernyi)杆状病毒诱导鸡异嗜白细胞的信号转导途径,确证其是否具有活化鸡异嗜白细胞的作用。采用β-葡萄糖苷酸酶释放法检测柞蚕杆状病毒诱导的鸡异嗜白细胞脱颗粒反应,并通过应用蛋白酪氨酸激酶(src、syk)、磷脂酰肌醇3-激酶(PI3-K)以及丝裂原活化蛋白激酶(ERK、p38 MAPK、JNK)的特异性抑制剂,分析各蛋白酶通路在柞蚕杆状病毒诱导鸡异嗜白细胞脱粒反应中的作用。结果表明,柞蚕杆状病毒可以显著提高鸡异嗜白细胞的脱粒反应,其中src、PI3-K、JNK的特异性抑制剂能够抑制柞蚕杆状病毒诱导的鸡异嗜白细胞的脱粒反应,而syk、ERK、p38 MARK的特异性抑制剂则对鸡异嗜白细胞脱粒不起作用,说明柞蚕杆状病毒可通过src→PI3-K→JNK信号转导通路来诱导鸡异嗜白细胞的脱粒反应。  相似文献   
8.
Background: Historically, histiocytic ulcerative (HUC) (or granulomatous) colitis of Boxer dogs was considered an idiopathic immune-mediated disease with a poor prognosis. Recent reports of dramatic responses to enrofloxacin and the discovery of invasive Escherichia coli within the colonic mucosa of affected Boxer dogs support an infectious etiology.
Hypothesis: Invasive E. coli is associated with colonic inflammation in Boxer dogs with HUC, and eradication of intramucosal E. coli correlates with clinical and histologic remission.
Animals: Seven Boxer dogs with HUC.
Methods: Prospective case series. Colonic biopsies were obtained at initial evaluation in 7 dogs, and in 5 dogs after treatment with enrofloxacin. Biopsies were evaluated by standardized histopathology, and fluorescence in situ hybridization (FISH) with probes to eubacteria and E. coli .
Results: Intramucosal E. coli was present in colonic biopsies of 7/7 Boxers with HUC. Clinical response was noted in all dogs within 2 weeks of enrofloxacin (7±3.06 mg/kg q24 h, for 9.5±3.98 weeks) and was sustained in 6 dogs (median disease-free interval to date of 47 months, range 17–62). FISH was negative for E. coli in 4/5 dogs after enrofloxacin. E. coli resistant to enrofloxacin were present in the FISH-positive dog that relapsed.
Conclusions and Clinical Relevance: The correlation between clinical remission and the eradication of mucosally invasive E. coli during treatment with enrofloxacin supports the causal involvement of E. coli in the development of HUC in susceptible Boxer dogs. A poor response to enrofloxacin treatment might be due to colonization with enrofloxacin-resistant E. coli .  相似文献   
9.
The phase behavior of zein films has been investigated at nano-scale using atomic force microscopy (AFM) and compared to the phase behavior of the bulk using a thermal characterization technique. The local surface properties of the films were evaluated as a function of water activity using AFM. The glass transition temperature (Tg) of zein films decreased with increasing water activity. Adhesion forces measured by the AFM force curves increased with increasing water activity. Topography of zein and zein fractions were evaluated both qualitatively and quantitatively by the use of AFM and dedicated software to calculate the surface roughness. It has been found that processing technologies (solvent casting, drop deposition and spin casting) has influence on the surface structures of films. The films which were formed by the alpha zein rich fraction were found to have highest roughness values. Sectional surface profiles revealed that α-zein films have mean roughness (Ra) of 1.808 nm and root mean square roughness (RMS) of 2.239 nm while β-zein films have mean roughness (Ra) of 1.745 nm and root mean square roughness (RMS) of 3.623 nm. The discussions conducted on the differences/similarities in the observations were based on the hydrophobic/hydrophilic properties and interactions of these zein fractions.  相似文献   
10.
Rice kernels of a transgenic high-amylose rice line and its wild type were examined by a high-resolution X-ray microtomography (XMT) and an environmental scanning electron microscope. Two-dimensional (2-D) cross-sectional images and 3-D objects from XMT were reconstructed and analyzed to elucidate their structural features. The lack of two isoforms of starch branching enzyme, termed SBEI and SBEIIb in high-amylose rice (HAR), resulted in a distinctly different grain inner density than wild-type rice (WTR). HAR had smaller, elongated starch granules with air spaces inside the kernels resulting in an opaque grain, whereas WTR had a tight endosperm with little air space and polygonal starch granules. XMT allowed a full 3-D characterization of the rice kernel structure and revealed that air space distribution was not uniform in the HAR kernel.  相似文献   
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