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21.
2010年11–12月,我们在伊朗南部Hara生物圈保护区调查并分析了黄喉岩鹭(Egretta gularis)和灰林银鸥(Larus heuglini)羽毛中的镍含量。根据方差分析,同一鸟种羽毛中镍含量在不同性别和年龄组之间均无显著差异,但这一结果的有效性受到本研究样本较小的影响。Student t检测结果表明灰林银鸥羽毛中镍含量高于黄喉岩鹭。雌性黄喉岩鹭羽毛中镍含量高于雄性,而雄性灰林银鸥羽毛中镍含量则高于雌性。  相似文献   
22.
Commercial areas containing Eucalyptus plantations have expanded in recent years due to increased demands for pulp, paper and bioenergy. One of the threats that can reduce Eucalyptus production is the eucalyptus rust disease caused by Austropuccinia psidii, a biotrophic fungus that affects a broad range of Myrtaceae. An accurate diagnosis tool for the early detection of rust disease could be useful in breeding programs for selection of resistant plants against rust, in phytosanitary purposes or in rust epidemics studies. The aim of the present work was to develop a SYBR Green-based quantitative real-time PCR (qPCR) assay for the early detection and quantification of A. psidii in Eucalyptus grandis leaves. Three sets of primers based on the A. psidii ribosomal DNA intergenic space region (IGS), beta-tubulin and elongation factor genes were designed and evaluated. The assays using the IGS primer set resulted in the highest detection efficiency, detecting a lower limit of 0.5 pg of A. psidii DNA. Under artificial inoculation in plants, A. psidii was detected immediately after pathogen inoculation until 240 h post-inoculation using qPCR. In field validation of the method, A. psidii was detected using qPCR in naturally infected leaves with or without rust symptoms. This easy and fast method can be used for an efficient detection of A. psidii in E. grandis leaves. The implications of this tool for rust studies are discussed below.  相似文献   
23.
The effect of nitrogen (N) application rate and sowing date on seed quality and pod production of four cultivars of okra (Abelmoschus esculentus L.) were examined. Seeds of four okra cultivars (cv. ‘Boyatiou’, ‘Veloudo’, ‘Clemson’, and ‘Pylaias’) were sown on 13 May (1st sowing) and 2 June (2nd sowing). Plants were subjected to three N levels: F1, F2, and F3 (150, 300, and 450 mg N L?1). The 2nd sowing improved flower induction and pod set, without however affecting pod size. The number of seeds per pod was not affected by sowing time, but the mean 100 seed weight was generally lower in the 2nd sowing. In all cultivars, except cv. ‘Veloudo’ germination increased in the 2nd sowing mainly as a result of lower seed hardness. Germination was also improved by increasing N levels, or by seed storage, acid scarification, or seed priming.  相似文献   
24.
Grain yield and protein content are traits of major importance in wheat breeding, but their combination is challenging due to a tight negative correlation. Protein yield and grain protein deviation have been proposed as selection criteria to simultaneously improve both traits. Sedimentation volume is an indicator of protein quality, which plays an important role for bread‐making quality in wheat. All these traits have been investigated in our study with 135 parental inbred lines, their 1,604 hybrids and 10 commercial check varieties evaluated at five environments. The focus of our study was to investigate the usefulness of the grain protein deviation and to define a bivariate model for calculating the grain protein deviation. Further, we compared line and hybrid wheat for grain yield and quality‐related parameters such as protein content and sedimentation volume. The grain protein deviation determined with a bivariate model delivered robust estimates of variance components and enabled a balanced selection of genotypes with improved protein content and grain yield across different quality classes. Although heterosis for protein content and sedimentation volume was negative, hybrids had a higher grain protein deviation as well as higher grain yield at a given sedimentation volume or a given protein content than line varieties.  相似文献   
25.
Fabrication of Ceftazidime (CTZ) loaded silk fibroin/gelatin (SF/GT) nanofibers (NFs) without the loss of structure and bioactivity of CTZ was demonstrated by electrospinning method. The structure, morphology and mechanical properties of the electrospun SF/GT nanofibrous mats were characterized using FT-IR, SEM and DSC. The drug release profile of different electrospun fibers was analyzed using spectrophotometric method, and also diffusion method was applied to assess the antibacterial effect of NFs. Cell viability was evaluated by MTT assay. The results show that the average diameter of drug loaded NFs at the optimum polymer to drug feeding ratio (10:1) was 276.55±35.8 nm, while increasing the feeding ratio to 1:1 increases the average diameter to 825.02±70.3 nm. FT-IR of drug loaded NFs was revealed that CTZ was successfully encapsulated into NFs while viability study approved cytocompatibility of SF/GT NFs. CTZ was released from NFs during 6 h, and formation of inhibition zone in diffusion test demonstrated the antibacterial effect of drug loaded NFs. Altogether, the CTZ loaded SF/GT NFs can improve the drug effectiveness particularly in the prevention of post-surgical adhesions and infections for wound dressing.  相似文献   
26.
The effects of feeding Artemia nauplii enriched with or without poly‐β‐hydroxybutyrate (PHB) and/or highly unsaturated fatty acids (HUFA) on Siberian sturgeon (Acipenser baerii) larvae were investigated. Feeding larvae with PHB‐enriched nauplii (PHB, PHB + HUFA) decreased the growth performance of the larvae. PHB affected the body composition by increasing the lipid content of the whole body and decreasing total saturated, monoenoic, n3, n6 and decosahexanoeic acid (DHA) in the larvae, indicating that the PHB addition affected lipid metabolism. A high activity of pepsin was observed in the digestive extracts of PHB treatments (PHB, PHB + HUFA), while PHB suppressed amylase activity in the intestine of the larvae. Based on molecular analysis, PHB changed the microbial community in the distal intestine of the larvae. The highest counts of goblet cells were observed in the HUFA‐containing treatments (HUFA, PHB + HUFA), indicating that HUFA addition may improve the mucosal barrier defence system. The overall quality of the larvae was evaluated by exposing them to different salinities and ammonia stress levels. PHB decreased survival rates in these challenges. Our results show that optimal PHB doses for bio‐encapsulation into Artemia remain to be determined for further application at the earliest larval stages of sturgeon.  相似文献   
27.
The diploid goatgrass Aegilops tauschii is considered the D-genome donor of bread wheat and has probably a centre of diversity in north of Iran. In order to measure the genetic diversity of and the relationships among different populations, varieties and subspecies belonging to Ae. tauschii in Iran, DNA was extracted from 48 accessions of Ae. tauschii collected across the geographic range of the species in the Country and the genetic diversity was assessed using AFLPs based on eight PstI/MseI +3 primer pairs resulted in 277 bands, 198 of which were polymorphic. High level polymorphism was detected, with an average of polymorphism rate of 0.715; relatively low genetic similarity (0.455) between accessions and significant difference between the lowest (0.179) and the highest genetic similarity (0.817). The Iranian Ae. tauschii populations showed high level of genetic diversity. The populations studied were divided into two groups: one group was mainly representing Northern populations collected from Southern Caspian Sea shore and the other group was mainly representing Northeast and Northwest populations. Based on the results of this study, it can be suggested that Ae. tauschii possesses two separate gene-pools in Iran: Northern and Northeastern–Northwestern. Considering the needs for introducing new characteristics and alleles for wheat improvement purposes, Ae. tauschii Iranian gene-pool is assumed to be of high importance for more investigation in the future.  相似文献   
28.
This research was aimed to investigate the prevalence and clinical impact of occult HBV infection in thalassemic patients with chronic HCV infection. In this cross-sectional study we have totally examined 60 patients suffering HBV and HCV infections by PCR and RT-PCR methods, respectively, in Kerman province of Iran. ELISA technique (RADIM, Italy) was used to detect anti-HBc, anti-HBs and HBsAg. The serum level of liver enzymes (SGOT, SGPT, DB, TB and ALK) were analyzed in the HCV infected patients (MAN, IRAN). Statistical analyses performed using t-test and Chi-square. We found that 27 cases (out of 60) were infected by HCV but HBV-DNA was not seen in HCV infected patients. Present findings also showed that none of samples were HBsAg positive but 9 (33%) (out of 27) HCV-RNA positive patients were anti-HBc positive and 11 (40.7%) were positive for anti-HBs. We found that SGOT, SGPT, DB, TB and ALK are above normal in 27 (100%), 19(70.3%), 12(44.5%), 15 (55.5%) and 15 (55.5%) RNA-HCV positive patients, respectively. The prevalence of hepatitis C infection is very high in thalassemic patients and based on other studies our results showed that the prevalence of HCV infection in Kerman is more than other provinces of Iran. In contrast with other studies HBV-DNA in these patients could not be detected, hence, it seems that occult HBV infection isn't frequent in Iranian thalassemic patients who suffering from chronic HCV infection.  相似文献   
29.
Gesunde Pflanzen - Management of plant nutrition using fertilizers is an approach to deal with drought and to increase water productivity in paddies. The aim of this study, therefore, was to...  相似文献   
30.
European Journal of Plant Pathology - Five populations of a new dagger nematode species were recovered from natural grasslands and forests of north and northwest Iran, and described based upon...  相似文献   
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