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排序方式: 共有256条查询结果,搜索用时 265 毫秒
71.
Rajab Mohammad Nazari Maryam Modanloo Mohammad Reza Ghomi Mahmoud Reza Ovissipor 《Aquaculture International》2010,18(5):837-841
For studying the effect of LHRH-A2 hormone on the induction of final maturation and ovulation of Persian sturgeon, 71 matured females and 20 matured males were
used. Five groups of breeders were injected with sturgeon pituitary gland hormone (50 mg per fish) and LHRH-A2 in dosages of 3.5, 7, 8 and 10 μg kg−1 for females and 3 and 5 μg kg−1 for males. Results showed that LHRH-A2 successfully induced final maturation and ovulation in females, and there was no significant difference between five groups
of breeders in ovulation proportion, fertilization rate, survival rate of incubation, survival of yolk-sac absorption period
and active feeding period of larvae. It can be concluded that the LHRH-A2 is a proper alternative for pituitary gland hormone in artificial propagation of Persian sturgeon. 相似文献
72.
Sameri MJ Sarkaki A Farbood Y Mansouri SM 《Pakistan journal of biological sciences: PJBS》2011,14(24):1109-1116
The aim of this study was evaluation the effect of Gallic acid on movement disorders and pallidal electrical power in animal model of Parkinson's Disease (PD). PD is clinically characterized by development of motor disturbances, such as bradykinesia, resting tremors, rigidity and a later loss ofpostural reflexes. Oxidative stress is a hallmark factor where the oxidation of dopamine generates Reactive Oxygen Species (ROS) and an unbalanced production ROS induces neuronal damage, therefor leading the neuronal death. Gallic Acid (GA) and its derivatives are present in the plant kingdom and acts as a potent antioxidant. Wistar male rats divided into seven groups randomly with 8 in each. Animals in all groups except control received 8 microg/2 microL 6-hydroxydopamine dissolved in normal saline contains 0.01% ascorbate or vehicle in right Medial Forbrain Bundle (MFB) and a bipolar wire electrode was implanted in the left globus pallidus nucleus of all animals under stereotaxic surgery. Two weeks later PD was approved by contralateral rotation signs induced by apomorphine and then movements and electrical power of pallidal were evaluated. Motor functions and pallidal electrical power were impaired and GA could improve motor dysfunctions and gamma wave power in parkinsonian rats' significantly with higher dose of GA (200 mg kg(-1)). Present result showed that GA may act as a potent antioxidant and free radical scavenger to reverse motor disorders and pallidal gamma wave power after 6-OHDA neurotoxicity in brain. 相似文献
73.
Seyed Reza Tabaei-Aghdaei Alireza Babaei Morteza Khosh-Khui Kamkar Jaimand Mohammad Bagher Rezaee Mohammad Hassan Assareh Mohammad Reza Naghavi 《Scientia Horticulturae》2007
Forty landraces of Damask rose were collected from 28 provinces (13 origin sites) in Iran and evaluated to determine the diversity among them. The investigated characters were: flower weight, flower diameter, peduncle length, number of petals, number of stamens and oil content. Pearson's coefficients showed that number of petals was positively correlated with flower weight (r = 0.642) and number of stamens (r = 0.630), while its correlation with peduncle length was negative (r = −0.53). A negative correlation was obtained between oil content and number of stamens (r = −0.60) which is useful for indirect selection of landraces with low number of stamens and therefore high amount of oil content. Cluster analysis based on five botanical characters and oil content separated the origin site 12, which included Guilan, Mazandaran and Golestan provinces with a specific climate condition of temperate humid, from other origin sites. This distinctiveness was already confirmed by the bi-plot of the principal components. The distribution of Damask rose landraces provided useful information for the future collection and for the genetic resource management in these origin sites. 相似文献
74.
75.
Nakhaee A Taheri T Taghikhani M Mohebali M Salmanian AH Fasel N Rafati S 《Veterinary parasitology》2004,119(2-3):107-123
Canids are natural reservoirs of Leishmania infantum and have been promoted as experimental hosts to decipher the pathogenesis of human visceral leishmaniasis (VL). In this study, the presence of IgG antibodies as well as the presence of mononuclear leukocytes reactive to different cysteine proteinases (CPs) were examined in 13 L. infantum-infected dogs (six with symptoms, seven asymptomatic). Cysteine proteinases which belong to papain-like enzymes known as clan CA are the most studied CPs of parasite protozoa. These molecules are expressed by the intracellular stages of the parasite and could be immunogenic. We studied Type II CP (CPA) and Type I CP (CPB) with its long C-terminal extension (CTE) which could be highly immunogenic. We showed that the level of antibodies reactive to rCPA is low in both symptomatic and asymptomatic dogs. In contrast, when CPB and CTE were used as antigens, the level of total IgG (with IgG2 superior to IgG1) reached higher values in asymptomatic dogs than in dogs with VL. While the peripheral blood mononuclear cell (PBMC) reactivity was significant when cultured in the presence of freezed/thawed (F/T) lysate, it remained low in presence of CP although always higher for PBMC recovered from asymptomatic dogs. We showed the importance of CPB and CTE in particular as a target of immune response and their potential use for serodiagnosis in asymptomatic dogs. 相似文献
76.
Ali Kadivar Habiballah Rashidzadeh Najmeh Davoodian Hasan Nazari Rohallah Dehghani Tafti Heidar Heidari Khoei Hasan Seidi Samani Jahangir Modaresi Ebrahim Ahmadi 《Reproduction in domestic animals》2021,56(2):287-291
Accurate diagnosis of foetal sex in pregnant mare is helpful for many breeders, both for private or commercial purposes. In this study, in order to pre-natal foetal sexing in equine, we used TaqMan duplex real-time PCR to detect the specific regions of SRY and TSPY genes on extracted cell-free foetal DNA from maternal blood. Peripheral blood samples from 50 pregnant Arabian mares with singleton foetuses were collected. Cell-free foetal DNA was extracted from maternal plasma, and duplex real-time PCR assays were performed with TaqMan probes and primers. Amplification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene was used as control of DNA extraction procedure. From the 50 sampled mares, 28 cases had female and 22 mares had male foetuses. The final results for 46 samples were conclusive, and from them, 43 cases were predicted correctly. Sensitivity, specificity and accuracy of the test were 90.48%, 96% and 93.48%, respectively. In conclusion, a TaqMan duplex real-time PCR was set up to pre-natal detection of foetal sex in equine. The method was fast and decreased the false-positive and false-negative results. The technique can be used as a routine procedure in farms by collecting only a blood sample. 相似文献
77.
Bita Naseri Alireza Marefat 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(2):179-195
The relationships between a number of agronomic practices, Fusarium root rot (FRR) measurements and yield variables were characterized
at different growth stages in 122 commercial bean fields in Zanjan, Iran. Mean FRR incidence, severity and index differed
among growth stages and years. A lower FRR index at growth stage R9 and higher yields were detected in Red beans compared
to Pinto and White beans. FRR severity affected the number of pods and seeds per plant. Despite the lack of an impact of initial
drought on FRR and yield factors, FRR levels were higher following frequent irrigations at 2–3 days intervals than at longer
intervals at R6-7. The highest FRR index at R6-7 (51.9%) and incidence at R9 (69.1%) were associated with the densest category
of plant populations. Yield components differed significantly between the levels of plant density at R9. FRR levels at V3
were lower for June plantings than for May-second-week plantings. Lower FRR ratings and higher yields were detected at a seeding
depth of 0–5 cm in comparison to 10–20 cm. At R9, FRR levels on beans following maize were lower than those following barley,
bean, tomato or wheat. At V3, FRR severity was greater in fields that received 50–500 kg/ha of urea compared to non-fertilized
fields. Greater mean FRR index at R6-7 and lower yield levels were associated with the greatest weed density compared to weed-free
fields. This new information benefits the systematic understanding of interactions between bean yield, FRR and various agronomic
variables at large-scale. 相似文献
78.
The gaseous BeH2 molecule has been synthesized by means of an electrical discharge inside a high-temperature furnace and identified with infrared emission spectroscopy. The antisymmetric stretching mode nu3 has been detected near 2179 reciprocal centimeters. The BeH2 molecule has a linear, symmetric structure with an r0 BeH bond length of 1.333761(2) angstroms. 相似文献
79.
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
80.
Khashayar Mohajershojaei Alireza Khosravi Niyaz Mohammad Mahmoodi 《Fibers and Polymers》2014,15(10):2139-2145
In this paper, laccase enzyme was immobilized onto zinc ferrite nanoparticle and the characteristics of enzyme immobilized nanoparticle (EIN) were evaluated by Fourier transform infrared (FTIR) and scanning electronic microscope (SEM). Enzymatic decolorization of dyes using EIN from single and binary systems was studied. Direct red 31 (DR31) and Acid blue 92 (AB92) were used as model dyes. The effects of several parameters such as EIN dosage, pH, and dye concentration on decolorization of dyes from single and binary systems were evaluated. The optimized amount of EIN, reaction time, and pH for decolorization of dyes from single and binary systems were 0.2 g (for DR31) and 0.3 g (for AB92), 40 min, and 3 in single systems and 0.2 g (for DR31 and AB92), 40 min, and 3 in binary systems, respectively. Dye decolorization kinetics followed Michaelis-Menten model. The results showed that enzymatic process using EIN was effective method to decolorize dyes from single and binary systems. 相似文献