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1.
This study was conducted to evaluate the effects of different levels of milk thistle meal on performance, blood biochemical indices, ileal bacterial counts and intestinal histology in laying hens fed diets containing different levels of metabolizable energy. A total number of 200 Leghorn laying hens (Hy‐Line W‐36) were randomly assigned to eight experimental treatments with five cage replicates of five birds each. Dietary treatments consisted of four levels of milk thistle meal (0%, 15%, 30% and 60%) and two levels of AMEn (11.09 and 12.34 MJ/kg) fed over a period of 80 days. In vitro studies revealed that the total phenolic component of milk thistle meal was 470.64 mg gallic acid equivalent/g of the sample, and its antioxidant activity for inhibiting the 2‐2‐diphenyl‐1‐picrichydrazyl free radical and reducing ferric ions was about 21% higher than that of butylated hydroxyltoluene (p < .05). Diets containing high level of AMEn led to improved egg production (p < .05), egg weight (< .05), egg mass (< .01) and feed conversion ratio (< .01). In addition, offering diets containing high energy significantly enhanced (< .01) serum triglyceride and malondialdehyde (MDA) concentrations as well as jejunal villus height. Dietary supplementation of 3% milk thistle meal resulted in the best feed conversion ratio (< .05), reduction of ileal Escherichia coli enumeration (< .01) and an enhancement in the villus height‐to‐crypt depth ratio (< .05). Furthermore, feeding incremental levels of this meal led to remarkable decrease in serum cholesterol, triglyceride and MDA (< .01) concentrations while significant increase in blood high‐density lipoprotein content and goblet cell numbers (< .05). The present findings indicate that milk thistle meal with high antioxidant and antibacterial properties in laying hen diets may improve health indices and productive performance.  相似文献   
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The dynamics of blood neutrophil acyloxyacyl hydrolase (AOAH) activity, the appearance of endotoxin (lipopolysaccharide, LPS) in blood and the role of blood neutrophil AOAH in the severity of Escherichia coli and endotoxin mastitis were investigated in early postpartum dairy cows experimentally challenged with either endotoxin (n = 6) or E. coli (n = 6). The AOAH activity of blood neutrophils started to decrease significantly at post challenge hours (PCH) 6-24 and 12-24 in the endotoxin and E. coli-challenged groups, respectively; it returned to pre-challenged values at PCH 48 in both endotoxin- and E. coli-challenged groups. The cows were classified as moderate and severe responders according to milk production loss in the non-challenged quarters at PCH 48. There were no severe responders in the endotoxin-challenged group. In the E. coli-challenged group, only 1 severe responder was identified. The pre-challenge neutrophil AOAH activity of the severe responder was approximately 30% lower than that of moderate responders. No LPS was detected in the plasma of endotoxin-challenged cows; neither was it found in the plasma of moderate responders in the E. coli-challenged group at any PCH. However, at PCH 6, a remarkable amount of LPS was detected in the plasma of the severe responder from the E. coli-challenged group. Furthermore, neutrophil AOAH activity was increased by approximately 70% in the severe responder at PCH 6, but it increased by only approximately 15% in moderate responders. This was followed by a decreased neutrophil AOAH activity at PCH 12-24 and 24-72 in moderate and severe responders, respectively; the decreased AOAH activity at those PCH was more pronounced in the severe responder. The pronounced decreased neutrophil AOAH activity during mastitis often coincided with extreme leukopenia, neutropenia and a maximal number of immature neutrophils in the blood. Our results demonstrate that a decrease in neutrophil AOAH activity results in the appearance of LPS in the blood, and low blood neutrophil deacylation activity could be considered as a risk factor for severe clinical coliform mastitis.  相似文献   
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Intramammary infections of dairy cows with Gram-positive bacteria such as Staphylococcus aureus (major cause of mastitis) have received a lot of attention because of their major economic impact on the dairy farm through production losses induced by an increase in somatic cell count. Management strategies, including greater awareness for efficient milking and hygienic measures, have limited the spread of Gram-positive bacteria and resulted in a significant decrease of proportion of S. aureus isolates and subclinical mastitis worldwide. Other organisms such as coliform subspecies and Streptococcus uberis, both environmental bacteria that cause clinical mastitis, have received less attention. Escherichia coli causes inflammation of the mammary gland in dairy cows around parturition and during early lactation with striking local and sometimes severe systemic clinical symptoms. This disease affects many high producing cows in dairy herds and may cause several cases of death per year in the most severe cases. It is well known that bacterial, cow and environmental factors are interdependent and influence mastitis susceptibility. Many studies, executed during the last decade, indicate that the severity of E. coli mastitis is mainly determined by cow factors rather than by E. coli pathogenicity. During E. coli mastitis, the host defense status is a cardinal factor determining the outcome of the disease. Today, we know that the neutrophil is a key factor in the cows' defense against intramammary infection with E. coli. Effective elimination of the pathogen by neutrophils is important for the resolution of infection and the outcome of E. coli mastitis. This review is a compilation of some major findings over the last 15 years concerning mainly host factors that modulate and influence neutrophil function and the mammary inflammatory reaction. The individual chapters address: virulence factors of E. coli strains, how neutrophils kill E. coli, connection between endotoxins, tumor necrosis factor-alpha and nitric oxide, severity classification of E. coli mastitis, lifespan of neutrophils, host factors that influence severity, tissue damage and production loss.  相似文献   
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Zagros forests are mainly covered byQuercus brantii L. coppices and oak sprout clumps occupy the forest area like patches. We investigated post-fire herbaceous diversity in the first growing season after fire. For this purpose neighboring burned and unburned areas were selected with the same plant species and ecological conditions. The data were collected from areas subjected to different fire severities. Overall 6 treatments were considered with respect to fire severity and the mi-crosites of inside and outside of oak sprout clumps including: unburned inside and outside of sprout clumps (Ni and No), inside of sprout clumps that burned with high fire severity (H), inside of sprout clumps that burned with moderate fire severity (M), outside of sprout clumps that burned with low fire severity (OH and OM). Different herbaceous com-position was observed in the unburned inside and outside of oak sprout clumps. The species diversity and richness were increased in treatments burned with low and moderate fire severity. However, in treatment burned with high fire severity (H), herbaceous cover was reduced, even-ness was increased, and richness and diversity were not significantly changed. We concluded that besides the microsites conditions in forest, fire severity is an inseparable part of the ecological effect of fire on her-baceous composition.  相似文献   
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Background: The protein of Niemann-pick type C1 (NPC1) gene promotes the egress of cholesterol from late endosomes and lysosomes to other cellular compartments and contributes to a process known as reverse cholesterol transport. This study aimed to examine whether promoter methylation of NPC1 is associated with risk of cardiovascular disease (CVD). Methods: Fifty CVD patients and 50 healthy subjects as the control group were recruited in this study. Promoter methylation of NPC1 gene was defined using a nested-methylation specific polymerase chain reaction method. Statistical analyses were done using the chi-square, t-test or ANOVA tests. Results: Our study showed that the frequency of semi-methylated promoter (methylated/unmethylated status) was significantly higher in CVD patients than that in controls (OR = 6.521, 95% CI = 2.211-19.215, P = 0.008). However, a completely methylated promoter (methylated/methylated status) was not detected in any subjects in either of the two groups tested. Additionally, the analysis of clinical data according to the methylation status of NPC1 gene demonstrated that serum levels of total cholesterol, total triglycerides, high low-density lipoprotein cholesterol (LDL-C) and low high-density lipoprotein cholesterol (HDL-C) are influenced by NPC1 methylation, so that subjects with a completely unmethylated promoter (Unmethylated/unmethylated status) held lower levels of total triglycerides, total cholesterol, LDL-C and higher levels of HDL-C. Conclusion: Our findings propose that the NPC1 promoter methylation is a probable mechanism that can result in reduced/impaired NPC1 expression/activity and may thus contribute to progression of CVD. Key Words: Niemann-pick type C1 (NPC1), Promoter methylation, cardiovascular disease  相似文献   
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We selected 15 beech trees (Fagus orientalis) from the study area in a mountainous region from 520 to 1310 m above sea level. Ground observations of the beech tree growth process from January to December 2004 in 7- to 15-day intervals were performed both visually and by measuring leaf chlorophyll concentration (chlorophyll meter SPAD-502). Results for the regression analysis showed that the leaved period positively correlated with the air temperature (r?=?.894). Anthesis and SPAD measurements have a negative relationship with air temperature and as temperature increases they appear earlier in the year. Anthesis and SPAD measurements had correlation coefficients of r?=??.883 and r?=??.855, respectively. The anthesis and bud bursting and leaf tip appearance have a negative relationship with increasing altitude from sea level and as altitude increases they appear later in the year. To make phenological events in deciduous broadleaf forests recognizable, we used a seasonal 8-day composite Moderate Resolution Imaging Spectroradiometer/Normalized Difference Vegetation Index (MODIS/NDVI). Prior to leaf expansion, NDVI increased from the 109th day of the year or earlier. Existence of the evergreen plants (Ruscus hyrcanus) on the ground and snow-melting exert an influence on inconsistency of phenology monitoring of MODIS/NDVI images. Regression analysis showed that there is a positive relationship between NDVI and SPAD measurements (chlorophyll content) in beech trees.  相似文献   
9.
Microbial indices and their spatial patterns are strongly affected by environmental factors. Spatial variability of soil properties is one of the most important causes of variability in soil microbial indices. This research was conducted in the Caspian forest to assess spatial variabilities and frequency distributions of microbial properties.Ninety soil samples were taken using a grid sampling design 40 9 40 m. Microbial indices, organic carbon,nitrogen and pH were determined. Soil variable distributions showed that microbial indices had abnormal distributions. Logarithmic transformation produced normal distribution. Spatial continuity using geostatistical(variogram) was studied and maps obtained by point kriging.The variograms revealed the presence of spatial autocorrelation. The results indicate that spatial dependence of soil microbial indices was affected by non-intrinsic factors and forest management procedures. The maps show that soil microbial indices and soil properties have spatial variability. The spatial pattern of microbial indices was correlated to organic carbon and nitrogen.  相似文献   
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Previously, we have reported that the injection of an expression vector containing Herpes simplex virus (HSV) Glycoprotein D-1 (gD-1) generated a significant antibody response in mice and protected them against HSV lethal challenge. We tested its potential to induce antibody and cell mediated immune responses in latently infected mice. Positive control group (KOS) and HSV gD-1 vaccinated mice demonstrated protection against a lethal ocularly challenge of 10(5.5) plaque-forming units (pfu)/eye of wild HSV-1 versus negative control groups. For neutralizing antibody titers, delayed-type hypersensitivity (DTH), lymphocyte proliferation responses, clinical evaluation and survival following lethal challenge, no considerable difference was observed between mice vaccinated with DNA plasmid and those vaccinated with KOS. KOS-vaccinated mice demonstrated the ability to completely prevent latency whereas DNA vaccinated group showed some degree of protection and displayed less latency than negative control groups and had considerably high levels of IFN-gamma and strong CTL responses versus negative control groups. It can be concluded that although immunization with the DNA vaccine is more effective in both protecting mice and induction of immune response, however it could not completely block the latent infection in sensory nerves.  相似文献   
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