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1.
G. Abdollahpour A. Raoofi J. Najafi F. Sasani E. Sakhaie 《Zoonoses and public health》2006,53(Z1):14-16
Peste des petits ruminants (PPR) is a highly contagious and infectious viral disease of domestic and wild small ruminants characterized by fever, erosive stomatitis, conjunctivitis, gastroenteritis and pneumonia. Goats are usually more severely affected than sheep. Peste des petits ruminants is caused by a paramyxovirus of the Morbillivirus genus. In March 2004, a flock of sheep in Tehran province with 430 deaths was visited. According to the history taken from the owner, at disease onset most of the deaths were recorded from adult sheep, 3 weeks later lambs (2 weeks to 4 months of age) showed the highest death rate. All animals from 3 months age received rinderpest vaccine 1 month after onset. Many of the lambs died just a few hours after their first sucking of the colostrum from infected mothers. Most of them showed very acute form of disease and died a few hours after onset of clinical signs. In clinical examinations most of the cases showed severe depression, high fever (41°C), anorexia, mocopulurent nasal discharge, erosive and necrotic stomatitis (dental path, hard palate and cheeks), diarrhoea and dehydration. Para‐clinical findings including histopathological, serological and haematological examinations also confirmed the presence of PPR in this flock. PPR outbreaks have been frequent in Iran in recent years. Further, we suggest that PPR is not a recent invader of Iran. The main difference in clinical signs between this outbreak and the same in other reports is that goats did not show any obvious signs of PPR. This might be due to the number of the goats (>1% of the flock) and keeping them separate from the sheep. The present article reviews the details of this outbreak in Iran. 相似文献
2.
A Najafi MH Najafi Z Zanganeh M Sharafi F Martinez‐Pastor H Adeldust 《Reproduction in domestic animals》2014,49(6):934-940
A soybean lecithin‐based extender supplemented with hyaluronic acid (HA) was assayed for effectiveness to improve the quality of frozen–thawed ram semen. HA has not been tested yet in an extender containing soybean lecithin for freezing ram semen. Thus, the aim of this study was to analyse the effects of soybean lecithin at 1% or 1.5% along with HA at 0, 0.5 and 1 mg ml‐1 in a Tris‐based extender on the motion characteristics, membrane integrity (HOST), viability, GSH peroxidase (GSH‐PX) activity, lipid peroxidation and acrosomal status after freezing–thawing. Semen was collected from four Mehraban rams during the breeding season and frozen in the six lecithin×HA extenders. The extender containing 1.5% lecithin supplemented with no HA yielded higher total motility (52.5%±1.6), viability (55.8%±1.6) and membrane integrity (44.5%±1.7), but the effects of the lecithin concentration did not reach signification. Linearity‐related parameters, ALH, BCF, lipid peroxidation, GSH‐PX activity, morphology and acrosomal status were not affected by the extender composition. In general, adding HA significantly decreased sperm velocity (1 mg ml‐1 HA), total motility (only with 1.5% lecithin), viability (1 mg ml‐1 HA for 1% lecithin; both concentrations for 1.5% lecithin) and membrane integrity. In conclusion, adding HA to the freezing extender supplemented with soybean lecithin failed to improve quality‐related variables in ram semen. Increasing the lecithin content could have a positive effect, but further studies are needed. 相似文献
3.
Integrated sensors and actuators are rapidly evolving to provide an important link between very large scale integrated circuits and nonelectronic monitoring and control applications ranging from biomedicine to automated manufacturing. As they continue to expand, entire microsystems merging electrical, mechanical, thermal, optical, magnetic, and perhaps chemical components should be possible on a common substrate. 相似文献
4.
Ghassempour A Nojavan S Talebpour Z Amiri AA Najafi NM 《Journal of agricultural and food chemistry》2004,52(21):6384-6388
In this approach, a derivatization method is described for monitoring of organic acids in fermentation media without any separation step. The aqueous phase of fermentation media was evaporated and heated in a silylation reagent to form trimethylsilyl (TMS) derivatives. The silylated compounds are analyzed by 29Si nuclear magnetic resonance (29Si NMR) and gas chromatography-mass spectrometry (GC-MS). 29Si NMR can qualitatively monitor the components produced in the Krebs cycle. Quantification of these compounds is investigated by using selected ion monitoring mode of mass spectrometry. In this mode, mass to charge (m/z) values of their [M - 15]+ ions, which are 465, 275, 247, 221, 335, 251, and 313 of TMS derivatives of citric, alpha-ketoglutaric, succinic, fumaric, l-malic, oxaloacetic, and palmitic (as an internal standard), acids, respectively, are used. The limit of detection and the linear working range for derivatized citric acid were found to be 0.1 mg L(-1) and 10-3 x 10(4) mg L(-1). The relative standard deviation of the method for five replicates was 2.1%. The average recovery efficiency for citric acid added to culture media was approximately 97.2%. Quantitative results of GC-MS are compared with those obtained by an ultraviolet-visible method. 相似文献
5.
An investigation of the effect of aquic conditions on Fe-oxides distribution and magnetic susceptibility (χlf) was conducted on selected soils from Southern Iran. Seven pairs of adjacent soil pedons with different soil moisture regimes (aquic and non-aquic), were selected. The average concentrations of poorly crystalline Fe (Feo) and total free Fe (Fed) in aquic soils were 0.2 and 0.07% respectively, and 0.45 and 0.9% in non-aquic soils, respectively. The ratio of Feo/Fed varied from 0.03 to 0.64. χlf ranged from 1.8 to 113 × 10?8 m3 kg?1 in the soil studied. The variation of χfd ranged from 0.0 to 9.65%. The χfd values observed in non-aquic soils were larger than in aquic soils (4.00% vs. 1.37%). Positive correlations were observed between χ and clay contents in both aquic and non-aquic soils; however, non-aquic soil samples showed a larger coefficient of determination. A positive correlation existed between χfd and χ in aquic and non-aquic soils. Higher values of χfd were observed at the soil surface of non-aquic soil samples than at deeper levels, suggesting a greater proportion of ultrafine grains. Of the soil properties that were assessed, clay, cation exchangeable capacity (CEC), Fed, Feo/Fed ratio, χlf and χfd contents, changed significantly in response to the aquic condition. 相似文献
6.
Edris Shabani Sahebali Bolandnazar Seyed Jalal Tabatabaei Nosratollah Najafi Saeedeh Alizadeh-Salteh Youssef Rouphael 《Journal of plant nutrition》2018,41(13):1662-1673
A greenhouse experiment was conducted to assess the effects of magnetic field, arbuscular mycorrhizal fungi (AMF), and phosphorus (P) concentration in the nutrient solution (0, 5, 10, 20, or 40 mg L?1) on the mobility and accumulation of P in soil and plant tissues of basil (Ocimum basilicum L.). The experiment was designed as a factorial combination and treatments were arranged in a completely randomized design with four replicates. Magnetic field increased water-soluble P in the soil and P concentration in plant shoot by 30.0% and 13.0%, respectively, in comparison to the control. The application of magnetic field and inoculation of AMF at 10 mg P L?1 increased the P translocation efficiency by 23.3% and 17.8%, respectively. Overall, our results demonstrated that the use of magnetic field and AMF could be an effective tool for enhancing of uptake and movement efficiency of P even at low concentrations. 相似文献
7.
Halimeh Mobarak Ezzatollah Fathi Raheleh Farahzadi Nosratollah Zarghami Sara Javanmardi 《Veterinary research communications》2017,41(1):41-47
Mesenchymal stem cells are undifferentiated cells that have the ability to divide continuously and tissue regeneration potential during the transplantation. Aging and loss of cell survival, is one of the main problems in cell therapy. Since the production of free radicals in the aging process is effective, the use of antioxidant compounds can help in scavenging free radicals and prevent the aging of cells. The aim of this study is evaluate the effects of L-carnitine (LC) on proliferation and aging of rat adipose tissue-derived mesenchymal stem cells (rADSC). rADSCs were isolated from inguinal region of 5 male Rattus rats. Oil red-O, alizarin red-S and toluidine blue staining were performed to evaluate the adipogenic, osteogenic and chondrogenic differentiation of rADSCs, respectively. Flow cytometric analysis was done for investigating the cell surface markers. The methyl thiazol tetrazolium (MTT) method was used to determine the cell proliferation of rADSCs following exposure to different concentrations of LC. rADSCs aging was evaluated by beta-galactosidase staining. The results showed significant proliferation of rADSCs 48 h after treatment with concentrations of 0.2 mM LC. In addition, in the presence of 0.2 mM LC, rADSCs appeared to be growing faster than control group and 0.2 mM LC supplementation could significantly decrease the population doubling time and aging of rADSCs. It seems that LC would be a good antioxidant to improve lifespan of rADSCs due to the decrease in aging. 相似文献
8.
Mahdi Najafi Ghiri Mahrooz Rezaei Abdolmajid Sameni 《Archives of Agronomy and Soil Science》2013,59(9):945-957
Zinc sorption–desorption by sand, silt and clay fractions of six representative calcareous soils of Iran were measured. Sand, silt and clay particles were fractionated after dispersion of soils with an ultrasonic probe. Zinc sorption analysis was performed by adding eight rates of Zn from 6 to 120 μmol g?1. For the desorption experiment, samples retained after the measurement of Zn sorption were resuspended sequentially in 0.01 M NaNO3 solution and shaken for 24 h. Results indicated that Zn sorption by soil fractions increased in the order clay > silt > sand, and correlated negatively with CaCO3 content and positively with cation exchange capacity (CEC) and smectite content. Results indicated that for all fractions, the Langmuir equation described the sorption rates fairly well. In contrast to sorption, Zn desorption from soil fractions increased in the order sand > silt > clay, and correlated positively with CaCO3 content, CEC and smectite content. Results showed that parabolic diffusion and two constant equations adequately described the reaction rates of Zn desorption. In general, for all soils studied, the coarser the particle size, the less Zn sorption and more Zn desorption, and this reflects much higher risk of Zn leaching into groundwater or plant uptake in contaminated soils. 相似文献
9.
Charles G. Brooke Negeen Najafi Katherine C. Dykier Matthias Hess 《Animal Science Journal》2019,90(5):696-701
There has been a great interest to identify a microbial marker that can be used to predict feed efficiency of beef cattle. Such a marker, specifically one that would allow an early identification of animals with high feed efficiency for future breeding efforts, would facilitate increasing the profitability of cattle operations and simultaneously render them more sustainable by reducing their methane footprint. The work presented here suggests that Prevotella copri might be an ideal microbial marker for identifying beef cattle with high feed efficiency early in their life span and in the production cycle. Developing more refined quantification techniques that allow correlation of P. copri to feed efficiency of beef cattle that can be applied by lay people in the field holds great promise to improve the economy of cattle operations while simultaneously reducing their environmental impact by mitigating methane production from enteric fermentation. 相似文献
10.
Abdollahpour G Raoofi A Najafi J Sasani F Sakhaie E 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(Z1):14-16
Peste des petits ruminants (PPR) is a highly contagious and infectious viral disease of domestic and wild small ruminants characterized by fever, erosive stomatitis, conjunctivitis, gastroenteritis and pneumonia. Goats are usually more severely affected than sheep. Peste des petits ruminants is caused by a paramyxovirus of the Morbillivirus genus. In March 2004, a flock of sheep in Tehran province with 430 deaths was visited. According to the history taken from the owner, at disease onset most of the deaths were recorded from adult sheep, 3 weeks later lambs (2 weeks to 4 months of age) showed the highest death rate. All animals from 3 months age received rinderpest vaccine 1 month after onset. Many of the lambs died just a few hours after their first sucking of the colostrum from infected mothers. Most of them showed very acute form of disease and died a few hours after onset of clinical signs. In clinical examinations most of the cases showed severe depression, high fever (41 degrees C), anorexia, mocopulurent nasal discharge, erosive and necrotic stomatitis (dental path, hard palate and cheeks), diarrhoea and dehydration. Para-clinical findings including histopathological, serological and haematological examinations also confirmed the presence of PPR in this flock. PPR outbreaks have been frequent in Iran in recent years. Further, we suggest that PPR is not a recent invader of Iran. The main difference in clinical signs between this outbreak and the same in other reports is that goats did not show any obvious signs of PPR. This might be due to the number of the goats (>1% of the flock) and keeping them separate from the sheep. The present article reviews the details of this outbreak in Iran. 相似文献