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41.
Nazifi S Razavi SM Mansourian M Nikahval B Moghaddam M 《Tropical animal health and production》2008,40(1):47-53
This study was carried out in two observational clinical studies. Study 1 comprised 50 adult crossbred cattle naturally infected
by Theileria annulata. Infected animals were divided into 4 subgroups with different parasitaemia (<1%, 1–3%, 3–5% and >5%). Study 2 comprised
20 adult crossbred cattle naturally infected by Anaplasma marginale. Infected animals were divided into 3 subgroups with different parasitaemia (<10%, 10–20% and 20–30%). In study 1, a significant
negative correlation (P < 0.001) was observed between parasitaemia and superoxide dismutase (SOD). Positive correlations (P < 0.001)
were observed between parasitaemia and lactate dehydrogenase (LDH) and mean corpuscular fragility (MCF). In study 2 positive
correlations (P < 0.05) were observed among parasitaemia and MCF and LDH activity. SOD activity had a negative correlation
with parasitaemia in cattle with parasitaemia lower than 10% but no significant correlation (P > 0.05) was observed between
SOD activity and parasitaemia in cattle with 10–20 and 20–30% parasitaemia. In comparison of both studies we came to the conclusion
that in theileriosis as the severity of disease increased the anaemia, MCF and LDH activity increased and SOD activity decreased
at any parasitaemia, but in anaplasmosis the anaemia, MCF and LDH activity increased at any parasitaemia but SOD activity
decreased only in early but not in advanced stages of disease. 相似文献
42.
The effect of in planta TIBA and L-proline onin vitro seedlings and cell culture of sugar beet was investigated. Sterilized seeds were grownin vitro on 1/2 MS medium supplemented with 0 or3 mg/l TIBA. Calli obtained on young leaves cultured on MS medium containing 1 mg/l
BAP, were used for the initiation of cell suspension cultures using MS basal composition supplemented with 0 or 50 mM proline.
Aliquots of 1 ml from cell suspension culture were inoculated onto the first somatic embryo induction MS medium containing
TIBA 0.5 mg/l, BAP 1.0 mg/l, and proline at 0 or 50 mM. After three weeks of culture, embryogenic calli were transferred to
the second embryo induction medium supplemented with NAA and BAP at 0.2 and 0.5 mg/l, respectively. The frequency of somatic
embryos of calli obtained from in plantaTIBA together with proline treatments on average was20 which was higher than that of the other treatments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
43.
Partitioning of the genotypes by environment interaction (GEI) is important in order to determine the nature of the GEI. The
objectives of this study were to assess the presence and nature of GEI for nine agronomic traits of rapeseed cultivars, and
to identify cultivars with favorable levels of stable oil production. Nine rapeseed cultivars, including seven open pollinated
and two hybrids, Hyola308 and Hyola401, were grown in ten environments under rain-fed warm areas of Iran. The GEI was significant
for all traits and was partitioned into components representing heterogeneity due to environmental index and the remainder
of the GEI. Among the all traits with a highly significant heterogeneity, the largest amount of heterogeneity removed from
the GEI was for seeds per pod and seed weight. We found GEIs for both oil content and seed yield were largely influenced by
differences in correlations among pairs of cultivars (86.8 and 71.4% of the GEI sum of squares, respectively), suggesting
that crossover GEIs (i.e., change in genotype rankings among environments) are present. The mean correlation of each cultivar
with all other cultivars ([`(r)]ii¢ \bar{r}_{{ii^{\prime}}} ) ranged from 0.53 to 0.83 for oil content and 0.86 to 0.96 for seed yield. A comparison was done of the significance of Sh-σi2 (stability variance derived from total GEI) and Sh-Si2 (adjusted stability variance derived from residual GEI) assignable to each genotype for oil content and seed and oil yield.
Based on Sh-σi2, three cultivars were unstable for oil content, whereas six cultivars were unstable for seed and oil yield. The removal of
heterogeneity revealed that one unstable cultivar for oil content and three unstable cultivars for oil yield were judged to
be stable. All cultivars with [`(r)]ii¢ \bar{r}_{{ii^{\prime } }} ≤ 0.63 were labeled unstable for oil content, whereas all with [`(r)]ii¢ \bar{r}_{{ii^{\prime } }} ≤ 0.94 were considered unstable for seed yield. The relationships between [`(r)]ii¢ \bar{r}_{{ii^{\prime } }} and Sh-σi2 were significant (P < 0.01) for oil content and seed yield. The results of rank correlation coefficients showed significant positive correlations
of Yield-Stability statistic (YSi) with oil content and oil yield. Cultivars such as Option500 and Hyola401 were identified as having stable, high levels to
seed yield and oil content. 相似文献
44.
This study was conducted to determine how land management in three ecosystems including forest, rangeland, and saline desert soils affects the activity and diversity of isoenzymes, and the kinetic and thermodynamic parameters of soil cellulase. Cellulase was chosen because it hydrolyzes cellulose, a major plant substance entering the soils. Soil samples were collected in October 2009 from a native forest, a native rangeland, and a native saline desert as well as adjacent cultivated fields in central Iran. Land use changes of the native forest, rangeland, and saline desert soils resulted in 79%, 47%, and 73% reductions in cellulase activity, respectively. The Michaelis constant (Km) increased but the maximum catalytic velocity (Vmax) decreased for soil cellulase as a result of cultivation in the study areas. The thermodynamic parameters (Ea and Q10) of soil cellulase were also affected by cultivation. Higher Ea and Q10 values were obtained for the native soils, but the lower values belonged to the cultivated soils. The cellulase zymographic pattern revealed different cellulase isoenzymes in the soils. The prevailing cellulase isoenzymes in the soils were found to have molecular weights of 62 and 74 kDa in the native forest, 86 kDa in the cultivated forest, 55 and 65 kDa in the native rangeland, and 72 kDa in the reclaimed saline areas. Evidence reveals that the sensitivity of soil cellulase kinetic and thermodynamic parameters to land management seems to be due to differences in the cellulase isoenzymes present in soils. 相似文献
45.
Fungal diseases and inappropriate sowing dates, the most important reducing factors in cumin fields of Iran, a case study in Khorasan provinces 总被引:1,自引:0,他引:1
46.
Carole E.R. Pitcairn Ian D. Leith David Fowler Ken J. Hargreaves Masoud Moghaddam Valerie H. Kennedy Lennart Granat 《Water, air, and soil pollution》2001,130(1-4):1037-1042
The foliar N content of bryophytes and Calluna vulgaris (L.) has been shown to be an indicator of atmospheric N deposition in the UK at a regional scale (1000km) and more recently on a smaller scale in the vicinity of intensive livestock farms. This work extends the geographical scale of the relationship between foliar N concentration of Calluna vulgaris and other ericaceous shrubs and N deposition with 2 measurement transects, one extending from northern Finland to southern Norway (2000 km) and the other extending from central Sweden to Stockholm, south east Sweden (330 km). Included in the second transect is a region of complex terrain in the Transtrand uplands, where the variation in N deposition with altitude and canopy cover was quantified using 210Pb inventories in organic soil. The relationship between foliar N (FN) and N deposition was shown to increase linearly with N deposition (ND) over the range 0.8% N to 1.4% N according to FN = 0.040ND + 0.793 (r2 = 0.70). The data are entirely consistent with earlier studies which together provide a valuable indicator of critical loads exceedance, the threshold value being approximately 1.5% N, which is equivalent to a N deposition of 20 kg N ha?1 y?1. 相似文献
47.
Mohammad Arjmand Azadeh Madrakian Ghader Khalili Ali Najafi Zahra Zamani Ziba Akbari 《Iranian Biomedical Journal》2016,20(2):77-83
Background:
Cutaneous leishmaniasis is one of the most important parasitic diseases in humans. In this disease, one of the responsible organisms is Leishmania major, which is transmitted by sandfly vector. There are specific differences in biochemical profiles and metabolite pathways in logarithmic and stationary phases of Leishmania parasites. In the present study, 1H NMR spectroscopy was used to examine the metabolites outliers in the logarithmic and stationary phases of promastigotes in L. major to enlighten more about the transmission mechanism in metacyclogenesis of L. major.Methods:
Promastigote was cultured, logarithmic and stationary phases were separated by the peanut agglutinin, and cell metabolites were extracted. 1H NMR spectroscopy was applied, and outliers were analyzed using principal component analysis.Results:
The most altered metabolites in stationary and logarithmic phases were limited to citraconic acid, isopropylmalic acid, L-leucine, ornithine, caprylic acid, capric acid, and acetic acid.Conclusion:
1H NMR spectroscopy could play an important role in the characterization of metabolites in biochemical pathways during a metacyclogenesis process. These metabolites and their pathways can help in exploiting a transmission mechanism in metacyclogenesis, and outcoming data might be used in the metabolic network reconstruction of L. major modeling. Key Words: Leishmania major, Metabolomics, Principal component analysis 相似文献48.
Roudgarnejad Samaneh Samdeliri Morteza Mirkalaei Amirabas Mousavi Moghaddam Mojtaba Nasheai 《Gesunde Pflanzen》2021,73(4):603-611
Gesunde Pflanzen - Humic acid comprises the major part of humic substances and the most important component of soil organic matter (humus) that increases crop yield and quality. This research aimed... 相似文献
49.
Talebi J Moghaddam A Souri M Mirmahmoudi R 《Tropical animal health and production》2012,44(2):355-360
The present study aims were to determine the profiles of changes in progesterone (P4) and 17-β-estradiol (E2) in the peripheral
blood of Markhoz goat (Iranian Angora) during estrous cycle, gestation, and parturition throughout natural breeding season.
Gestation length averaged 145.3 ± 0.8 days, and the litter size was 1.1 ± 0.1. Birth weight ranged 2.4–2.8 and 1.5–2.5 kg
in male and female kids, respectively. The mean estrous cycle lengths were 20.3 ± 0.4 and 20.9 ± 0.4 days for PGF2α-induced and natural cycles, respectively. Blood sampling was carried out daily during estrous cycle and weekly during gestation
till parturition. E2 attained higher level (24.7 ± 2.15 pg mL−1) at estrus phase and dropped down to the lower level (18.80 ± 1.16 pg mL−1) within 3 to 4 days post-estrus. Concomitantly, P4 started to increase from the mean basal value of 0.5 ± 0.03 ng mL−1 on day 0 to 6.88 ± 0.95 ng mL−1 on day 6 of estrous cycle and reached the peak value of 12.8 ± 0.61 ng mL−1 on day 12. From day 15, a decline was observed in P4 values till the end of the cycle. P4 remained at lower concentrations
for 20–50 days of gestation, then increased and reached to its maximum level (13.51 ± 0.279 ng mL−1) in week 15 and returned again to its basal values within 1–2 weeks before parturition. The results will be discussed in
terms of the usage of steroid hormone profile in several assisted reproductive technologies. 相似文献
50.
Mojghan Tabrizivand Taheri Seyed Siamak Alavi-Kia Seyed Abolghasem Mohammadi Mohammad Moghaddam Vahed 《Genetic Resources and Crop Evolution》2018,65(7):1867-1878
Einkorn wheat is known as the donor of ‘A’ genome to cultivated wheat and source of many important genes. Therefore, genetic erosion in cultivated wheat provides a good reason to investigate genetic diversity in these species. In the present study, genetic diversity of 14 populations of Triticum urartu and Triticum boeoticum collected from west and north-west of Iran was examined by IRAP and REMAP markers. In total, 26 out of 36 IRAP and 41 out of 88 REMAP combinations amplified polymorphic and scorable banding patterns. IRAP and REMAP combinations produced 6.53 and 5.21 polymorphic bands per assay, respectively. Mean of polymorphism information content for IRAPs and REMAPs were 0.38 and 0.40 and marker index values for them were 2.60 and 2.09, respectively. Analysis of molecular variance based on IRAP and REMAP data revealed significant within and among population variances, although within population variance was higher than that of among population. Primer combinations based on Sukkula and Nikita retrotransposons produced the highest number of markers in the whole population. Cluster and principal coordinate analyses using REMAP data grouped the populations based on the species and geographical origin, but grouping based on IRAP could not separate the two species. However, based on both marker systems considerable diversity was observed among and within the studied populations. 相似文献