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51.
This study aimed to evaluate color Doppler sonographic findings in carotid arteries in RA patients under pharmacological treatments and to compare them with normal population. Forty nine patients with late RA and 48 healthy age and sex-matched controls were recruited. The two groups were matched for other known risk factors of atherosclerosis including serum lipid abnormalities, smoking status, diabetes mellitus and hypertension. High resolution B-mode color Doppler ultrasound with a 7 MHZ transducer was used for measuring the Common Carotid Intima-Medial Thickness (CCIMT) in both sides in all subjects. Presence of atherosclerotic plaque was also investigated. The mean left and maximum CCIMT was significantly higher in the case group (0.72 vs. 0.62 mm for the left artery; p < 0.01; 0.72 vs. 0.64 mm for the maximum reading; p = 0.01). No atherosclerotic plaque was found in common carotid arteries. There were 3 (6.1), 7 (14.3) and 9 (18.4%) plaques in left internal carotid artery, right carotid bulb and left carotid bulb in the case group, respectively with no atherosclerotic plaques in the controls (p = 0.24, 0.01 and < 0.001, respectively). Comparing the findings by gender in the case group with the controls, the mentioned significant differences were only between the male patients and the controls. The process of atherosclerosis in RA patients is similar to that in normal population. However, it is apparently accelerated and more advanced in these patients.  相似文献   
52.
The objective of this study was to determine the effects of various methods of sperm pre‐treatment on male pronuclear (MPN) formation and subsequent development of ovine embryos derived from in vitro‐matured oocytes and intracytoplasmic sperm injection (ICSI). The effect of treatment of injected oocytes with dithiothreitol (DTT) on embryo development was also assessed. In Exp. 1, the injected oocytes with non‐treated sperm were activated with three different procedures. The cleavage and blastocyst rates in those activated with DTT was lower (p < 0.05) than those activated with either ionomycin (Io) + 6‐dimethylaminopurine (6‐DMAP) or DTT + I + 6‐DMAP. In Exp. 2, the effects of sperm pre‐incubated with DTT, sodium dodecyl sulphate (SDS) or DTT + SDS as well as two‐time frozen/thawed sperm (without cryoprotectant) on MPN formation and oocyte activation were examined. The non‐treated sperm served as controls. The MPN formation in DTT + SDS group was higher (p < 0.05) than other groups except for freeze–thaw group. No difference in the rate of activated ICSI oocytes was observed among groups. In Exp. 3, the effect of pre‐treatment of sperm on subsequent development of ICSI embryos and blastocyst cell numbers were examined. The rates of cleavage and blastocyst formation as well as the blastocyst cell numbers were similar among the pre‐treated and control groups. In conclusion, pre‐treatment of sperm with DTT + SDS positively affected MPN formation, although the subsequent development capacity of the resulting embryos remained limited. Moreover, DTT was not effective on oocyte activation compared with Io + 6‐DMAP after ICSI.  相似文献   
53.
This study investigated the effect of pentoxifylline (PTX) and Basal Medium Eagle (BME) on frozen–thawed goat spermatozoa. Immediately after initial examination of ejaculated semen, samples were pooled and reexamined for quality. Then, samples were divided into eight equal aliquots and diluted with a basic tris-extender containing PTX (3, 6, 9 mM) and BME (5 mM) to reach a final concentration of 25 × 109 and frozen. After 24 hr, the samples were individually thawed at 37°C for 30 s and evaluated for different characteristics. Obtained post-thaw results from Computer-Assisted Sperm Analysis indicate using of 3 and 6 mM PTX led significantly to an improvement in total motility, progressive motility and velocity characteristics of spermatozoa, except the beat/cross frequency (BCF) which indicated statistically no differences (p > .05) among control and treatments. Diluents prepared with BME (5 mM) and PTX alone (3 and 6 mM) improved significantly the membrane integrity–functionality, acrosome integrity and also hyaluronidase activity. Regarding recovery rate, the results showed significantly (p < .05) higher values for diluents containing 3 and 6 mM PTX compared to other groups. Malondialdehyde concentration exhibited also a significant difference (p < .05) in diluents supplemented with 5 mM BME, 3, 6 and 9 mM PTX, and mixture of 3 mM PTX and 5 mM BME which illustrate a similarity for active mitochondria, apoptotic-like and dead spermatozoa. Finally, the ratio of sperm chromatin dispersion stained spermatozoa presented significant differences (p < .05) among treatments in which the diluents added PTX alone demonstrated significantly lower values than control and extenders containing the mixtures of BME and PTX. In conclusion, the observation in this study indicates using of 3 and 6 mM PTX and BME alone may improve significantly (p < .05) the quality of cryopreserved goat spermatozoa.  相似文献   
54.
Wheat (Triticum aestivum L.) is one of the most widely cultivated crops in rainfed areas of Iran, where drought is the main limiting factor on yield. The object of this study was the identification of drought-tolerant genotypes in bread wheat. Forty bread wheat genotypes were tested in separate experiments under drought stress and normal conditions in two years (2009–2010 and 2010–2011). Nine drought-tolerance/susceptibility indices including stress susceptibility index (SSI), mean productivity (MP), tolerance (TOL), stress tolerance index (STI), geometric mean productivity (GMP), yield index (YI), yield stability index (YSI), linear regression coefficient (β) and drought response index (DRI) were determined. Simultanously applied factor analysis used two factors instead of nine indices in this study. Mahdavi was recognized as the most drought-tolerant genotype in both years based on factor analysis. In this study an equation was developed for estimating the Stress Tolerance Score (STS). The results of the equation were identical to those of factor analysis in both years. The equation was much easier to use than factor analysis and is suggested as a screening tool for the identification of drought-tolerant genotypes. In this study, Mahdavi was the most drought-tolerant genotype also corresponding to this equation.  相似文献   
55.
Abstract

Optimisation of water and nitrogen use is an effective management tool to conserve resources and reduce environmental pollutions. Response surface methodology (RSM) is defined as a collection of mathematical and statistical methods that are used to develop, to improve or to optimize a product or process. In order to determine optimum levels of water, nitrogen and planting density of canola (Brassica napus L.), a 2-year experiment (2010–2011) was carried out by central composite design as RSM at the research station of Ferdowsi University of Mashhad. The treatments were designed based on low and high levels of irrigation (1500 and 4000 m3 ha?1), nitrogen (0 and 400 kg N ha?1) and density (50 and 150 plant m?2) as independent variables. Furthermore, seed yield, nitrogen losses, nitrogen use efficiency (NUE) and water use efficiency (WUE) were measured as response variables in a full quadratic polynomial model. Optimum levels of irrigation, nitrogen and planting density were suggested to achieve the target range of dependent variables based on three scenarios: economic, environmental and eco-environmental. The results showed that increasing irrigation and fertilizer led to an increase in seed yield and nitrogen losses, whereas increasing canola density resulted in an increase in seed yield but a decrease in nitrogen losses. The optimum levels of water, fertilizer and density based on environmental scenario were 1802 m3 ha?1, 11 kg N ha?1 and 122 plant m?2, respectively. To achieve optimum conditions under the economic scenario, it is necessary to use 3411 m3 water ha?1, 178 kg N ha?1 and 119 plant m?2. Amounts of 2347 m3 water ha?1, 92 kg N ha?1 and 114 plant m?2 were found to be the optimum conditions for the eco-environmental scenario. In general, it seems that resource use based on the eco-environmental scenario may be the most favorable cropping strategy for canola production.  相似文献   
56.

The two-location field experiment was conducted to investigate the effect of Thiobacillus and different levels of sulfur fertilizer on growth and physiological indices in the replacement intercropping of sesame and mung bean. A factorial experiment was performed based on a randomized complete block design in 3 replications in 2018. The experimental factors consisted of cropping ratio at five levels: 1. sesame sole cropping, 2. mung bean sole cropping, 3. 75% sesame +25% mung bean (3:1), 4. 50% sesame +50% mung bean (1:1), 5. 25% sesame +75% mung bean (1:3). Sulfur fertilizer was used at three levels: control level (S0), 50% of recommended amount (S1), 100% of recommended amount (S2). Thiobacillus bacteria was used at two levels: T0 and T1. The results showed that growth indices chlorophyll a, chlorophyll b, total chlorophyll, biological yield, and grain yield of sesame and mung bean were significantly affected by the studied treatments. The highest growth indices, chlorophyll a, chlorophyll b, total chlorophyll, biological yield and grain yield of sesame were obtained by the 3:1 ratio. For the mung bean, the highest growth indices, chlorophyll a, biological yield, grain yield were obtained by mung bean sole cropping and the highest chlorophyll b and total chlorophyll were obtained by the 1:1 ratio. Also, sulfur fertilizer, 100% of the recommended amount, increased all studied indices in both plants except for chlorophyll a in sesame. Interaction effects of cropping ratio and location on growth indices, grain biological yield, chlorophyll a of sesame and mung bean were significant.

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57.
58.
Preeclampsia is a disease regarding with altered vascular reactivity leading to hypertension of the mother and metabolic alterations in the fetus. This study aimed to assess nitric oxide and bleeding time following administration of magnesium sulfate to preeclamtic patients compared to normotensive pregnant women. A total of 112 subjects (56 preeclamtic patients and 56 normotensive pregnant controls) were enrolled in this case-control study. Cases and controls were matched for age, BMI, gestational age, parity and gravidity. Total concentration of nitrite and nitrate (NOx) was measured before and during magnesium sulfate (MgSO4) treatment using a modified Griess-based method. RESULTS: Systolic and diastolic blood pressures were significantly decreased during MgSO4 treatment in preeclamtic patients (p < 0.0001). NOx levels were significantly increased in preeclamtic women after MgSO4 administration (33.7 +/- 18.5 vs. 50.2 +/- 21.6, p < 0.0001) but it was not seen in normotensive parturients (52.4 +/- 28.9 vs. 57.3 +/- 21.7, p = 0.362). The bleeding time was scarcely increased following magnesium sulfate treatment in preeclamptic patients compared to normotensive pregnant women but it was not significant (p = 0.18). In addition, there was only a significantly reverse correlation between NOx levels and systolic or diastolic blood pressure in preeclamtic parturients after MgSO4 treatment (r = -0384; p = 0.003 and r = -0.29; p = 0.03, respectively). This study demonstrates that administrating MgSO4 to preeclamtic patients induced significant changes in NOx production which had a major role in modulating vasculature changes in preeclamsia.  相似文献   
59.

To investigate the effect of different planting dates and irrigation regimes on six canola cultivars, a 2-year (2014–2016) experiment was conducted at the Seed and Plant Improvement Institute of Karaj. The experiments were conducted as the factorial split-plot in a randomized complete block design including six canola cultivars (Gabriella, Brutus, Triangle, Marathon, Danube, and Natali), two irrigation regimes (fully irrigated and irrigation termination at the flowering stage) and two planting dates (October 1 and November 1). The results showed that irrigation termination from the flowering stage prevented the supply of required material for filling the seeds and the metabolism of the seed compounds and reduced the growth period of the seed. Therefore, a reduction was observed in the content of oleic and linoleic acids and proline. Also, water deficit stress caused an increase in the glucosinolate content of the seed. The response of canola cultivars was different in terms of fatty acids, so that the Natali cultivar had higher palmitic, oleic acids, and proline content compared to the other cultivars at both planting dates. Fully irrigated treatment and planting date of October 1 produced the highest amount of seed and oil yield (4659 and 2073?kg ha?1), palmitic acid (5.5%), and proline (22.7?μmol/g) content, and the lowest glucosinolate content (13.2?mg/g). Generally, the Natali cultivar and planting date of October 1 and the fully irrigated regime are highly recommended in the studied area regarding qualitative traits and yield of canola.

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60.
The aim of this study was to evaluate the effects of different doses of dietary soy meals (with or without isoflavone) on dementia in ovariectomized (OVX) animal model of Alzheimer's disease. Female Wistar's rats with the exception of intact group were ovariectomized at the first line of study. Animals were divided into 2 main groups: control (c) and pre-treatment groups. Animals in pre-treatment groups received one of five types of diet during four weeks prior Nucleus Basalis Magnocellularis (NBM) electrical lesion normal diet (0), 10 g soy with isoflavone (10), 20 g soy with isoflavone (20), 10 g soy without isoflavone (-10) and 20 g soy without isoflavone (-20) in 30 g daily diet. The spatial learning and memory were tested using Morris water maze after electrical lesion. Rats were trained in water maze to find a hidden escape Platform. Rats received 6 blocks that each block consisted of 3 trials. Following acquisition trials, one probe trial was conducted in which the platform was removed. Soy meal diet (with or without isoflavone) in ovariectomized rats with Alzheimer's disease caused improvement of performance across 18 trials of Acquisition. Our results suggest that soy meal is a potential alternative to estrogen in the prevention and treatment of Alzheimer's disease.  相似文献   
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