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961.
The aim of this study was to investigate the effects of time, particle size (PS) and level of calcium supplementation above the requirements toward the end of the laying period on egg production and eggshell quality. A total of 675 Isa-Brown layer hens were distributed in a completely randomized factorial arrangement of 3×3×3, using three sprinkling times (08.00, 12.00, 16.00 hours), PC (mash, granular and large size) and amounts (0 g control, 0.75 g/day/h, 1.50 g/day/h) of marble sprinkling as a calcium source. All hens were fed a commercial layer diet from 55 to 67 weeks of age. Sprinkling of 1.50 g marble reduced ( P  < 0.05) egg production compared to 0.75 g marble, and feed efficiency (FE) compared to that of 0 and 0.75 g marble. Sprinkling of 0.75 and 1.50 g marble increased ( P  < 0.01) eggshell weight, shell strength and shell thickness compared to that of 0 g marble. The interaction of sprinkling time-by-PS-by–quantity of marble was significant for egg production ( P  < 0.05), FE and shell strength ( P  < 0.01). Results showed that sprinkling of coarse marble powder to complete diet increased shell strength without reduction in egg production and FE.  相似文献   
962.
库尔勒香梨历年冬季低温评价及严重冻害成因分析   总被引:12,自引:3,他引:9  
通过评价1958-2008年库尔勒香梨越冬期间及早春低温资料,分析了历年冻害发生情况及冻害成因.结果表明:1958-2008年,气温异常偏低年份有9年,香梨发生了6次严重冻害,其中5次严重冻害发生在越冬期间,早春冻害1次(2005),剩余3年气温在临界线附近,没有造成严重冻害;1958-1986年极端最低气温变化趋势基本正常,之后有升高趋势;2007-2008年冬季气温异常偏低,导致了大面积冻害;香梨冻害发生临界温度大致为-20 ℃;香梨冻害与极端低温、低温持续日数、降温幅度、降雪厚度及持续时间、立地条件及管理水平等因素有关.  相似文献   
963.
BACKGROUND: Calprotectin is cytotoxic agent that its anti-tumor effects are governed through suppression of topoisomerase II; a key enzyme in apoptosis. In previous studies, cytotoxicity and apoptotic effects of calprotectin are shown on different cancer cell lines, but not human gastric cancer cell lines. In the present study, cytotoxicity and apoptotic effects of calprotectin on human gastric adenocarcinoma cancer cell line (AGS) were evaluated. METHODS: The AGS cells were exposed to the different concentrations of calprotectin for 24, 48 and 72 hours. Cell proliferation was assessed using dimethylthiazol diphenyl tetrazolium bromide assay and dye exclusion tests. For evaluation of cytotoxic mechanism in calprotectin on AGS cells, flow cytometric analysis was performed. RESULTS: Our results revealed that calprotectin induces growth inhibition of AGS in a dose- and time-dependent manner. Results of this investigation showed that sensitivity of AGS cells to cytotoxic effect of human calprotectin was highly remarkable. In addition, growth inhibitory effect of this cytotoxic agent mostly was governed through induction of apoptosis in the AGS cells. CONCLUSION: These findings indicated that calprotectin induces growth inhibition and apoptosis in the AGS cells.  相似文献   
964.
BACKGROUND: Congenital Adrenal Hyperplasia (CAH, the inherited inability to synthesize cortisol) is one of the most common (1 in 10000 to 1 in 15000) autosomal recessive disorders. More than 95% of cases of CAH are caused by 21-hydroxylase deficiency (21-OHD). Females with severe, classic 21-OHD are exposed to excess androgens prenatally and are born with virilized external genitalia. Most patients cannot synthesize sufficient aldosterone to maintain sodium balance and may develop potentially fatal salt wasting crisis if not treated. METHODS: We applied allele specific PCR to detect the eight common mutations in the CYP21 gene in patients. Fifty unrelated patients with symptoms of classical CAH were studied. RESULTS AND CONCLUSION: Seventy percent of our subjects had these mutations. The most frequent mutations were found to be I2G and del-8 bp (28% and 13%, respectively). The frequencies of other alleles were as following: I172N, 9%; V281L, 3%; exon 6 cluster (I236N, V237E and M239K), 4%; Q318X, 9%; R356W, 5%; and P30L, 0%. The frequency of mutations did not differ substantially from other ethnics, however, a higher rate of del-8 bp (13%) was found in our population. The aim of this study was to detect common mutations for setting up a molecular method for prenatal diagnosis.  相似文献   
965.
The date palm, Phoenix dactylifera, is a palm extensively cultivated for its edible fruit. The chemical composition and the water content of ten Tunisian date varieties were determined. For all analysis, the Deglet Nour variety was taken as reference. Compositional analysis showed that the littoral varieties were very rich in reducing sugars (26 to 51%) than Deglet Nour which was rich in sucrose (54%). The relative results of the moisture content showed that the littoral varieties were classified as soft dates. The vitamin C analysis showed that the littoral varieties were very rich in this compound (24 to 46 mg/100 g) than Deglet Nour (1.12 mg/100 g). The mineral analysis showed that the littoral dates were relatively rich in potassium (283 to 733 mg/100 g) and presented a weak content in sodium (0.06 to 0.09 mg/100 g).  相似文献   
966.
Gaucher's disease is a rare lipid storage disorder, affecting one in 40,000-200,000 people and results from a genetic deficiency of the enzyme glucocerebrosidase (glucosylceramidase). We report a 10-year old Iranian girl with chief complaint of anemia from 8 years ago, managed for iron deficiency anemia. The patient had hepatomegaly associated with huge splenomegaly which was confirmed by sonography. No skeletal disorder was found. Bone marrow aspiration revealed typical Gaucher cells. Low level of beta-glucocerebrosidase enzyme activity confirmed the Gaucher disease. The patient is now under treatment with CEREZIME, a recombinant DNA modified form of glucocerebrosidase with good condition.  相似文献   
967.
The scaling technique in calculating Palmer Drought Severity Index (PDSI) has specific properties, which is considered in details, in this study. The Palmer scaling method contains a physically-based weighting factor called climatic characteristic coefficient, K. This factor, is the ratio of average moisture demand to average supply in a regional water balance, whose related coefficients and involved equation parameters should be calibrated according to any special case study. Therefore, in this study, the generalizing procedure of obtaining K-value with no dependency on particular area, in addition to some modifications in the process was analytically developed. The generalized procedure has an appropriate potential for various purposes such as; correctly identifying analytical K-formula, simplifying its application, recognizing its limitations and moreover it can be used in other researches for developing its advantages. The proposed procedure and its modifications also applied for a case study (e.g., Maharlue catchment, Fars province, Iran). The outputs of the application validated the suggested modifications; therefore, the obtained K-values can be used for other studies in the region.  相似文献   
968.
A field experiment was conducted during 2001-2003 to evaluate the effect of water stress on the yield and yield components of four rice cultivars commonly grown in Mazandaran province, Iran. In northern Iran irrigated lowland rice usually experiences water deficit during the growing season include of land preparation time, planting, tillering stage, flowering and grain filing period. Recently drought affected 20 of 28 provinces in Iran; with the southeastern, central and eastern parts of the country being most severely affected. The local and improved cultivars used were Tarom, Khazar, Fajr and Nemat. The different water stress conditions were water stress during vegetative, flowering and grain filling stages and well watered was the control. Water stress at vegetative stage significantly reduced plant height of all cultivars. Water stress at flowering stage had a greater grain yield reduction than water stress at other times. The reduction of grain yield largely resulted from the reduction in fertile panicle and filled grain percentage. Water deficit during vegetative, flowering and grain filling stages reduced mean grain yield by 21, 50 and 21% on average in comparison to control respectively. The yield advantage of two semidwarf varieties, Fajr and Nemat, were not maintained under drought stress. Total biomass, harvest index, plant height, filled grain, unfilled grain and 1000 grain weight were reduced under water stress in all cultivars. Water stress at vegetative stage effectively reduced total biomass due to decrease of photosynthesis rate and dry matter accumulation.  相似文献   
969.
Plant nutrients can be influenced by organic materials of soils. An experiment was conducted to evaluate the effect of organic amendments on elements uptake by soybean cultivars in a silty loam soil in Mazandaran province, Iran. The experiment was carried out in split plot based on randomized complete block design with three replications in 2006. Main plots were included 8 fertilizer treatments consisted of 20 and 40 Mg ha(-1) Municipal Solid Waste Compost (MSW), Vermicompost (VC) and Sewage Sludge (SS) which enriched with 50% chemical fertilizers needed by soil, only chemical fertilizer treatment and control. Sub plots consisted of three genotypes of soybean (032, 033 and JK). Grain yield was determined and soybean leaves and seeds were digested and analyzed for Mn, Cu, Zn and Fe. Results showed that yield and elements content in soybean leaves and seeds (Mn, Cu, Zn and Fe) were influenced by all treatments. The 40 Mg ha(-1) of sewage sludge enriched with chemical fertilizers produced maximum grain yield. Different soybean cultivars had also significant differences in terms of leaf and seed micronutrients accumulation. Maximum grain yield was observed in JK and 033. Mean comparisons showed that interaction effects of fertilizer and cultivar had significant differences on Mn, Cu and Fe content in soybean leaves, so that the maximum Cu content was observed in 032 cultivars with 40 Mg ha(-1) enriched sewage sludge and municipal waste compost. Also the highest amount of Fe was obtained for JK cultivar when the 40 Mg ha(-1) of municipal compost was used. Among different mentioned traits, Fe and Cu content in leaf and seed and Zn content in leaf had a positive and significant correlation with grain yield.  相似文献   
970.
草酸青霉菌(P-o- 41)发酵液对小麦病害的诱导抗性作用   总被引:1,自引:0,他引:1  
不同浓度的草酸青霉菌(P-o- 41)[1,2]发酵代谢物处理珊西烟的一张叶片,在另外的叶片上摩擦接种TMV,比较处理叶片与无菌蒸馏水对照叶片上的枯斑数.结果表明,稀释1 000倍的发酵代谢物处理及百万分之三十八的BTH处理与清水处理对照相比,枯斑抑制率(;)分别达到84.05;和79.96; ;对小麦白粉病的诱抗效果分别达到60.88; 和69.43; ;对小麦普通根腐病的抑制率在P0.01水平上达到显著差异,而平板圆盘测定结果表明,草酸青霉菌(P-o-41)发酵液对小麦根腐病菌无抑制作用.  相似文献   
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