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21.
Citrus tristeza virus (CTV) has existed in northern Iran for more than five decades. The long-time interaction of different virus genotypes with Aphis gossypii, as the only aphid vector of CTV in northern Iran, has led to the emergence of highly virulent subpopulations, among others, in the established foci. Here, we studied the population structure of the originally established CTV isolates present in Satsuma mandarin (Citrus unshiu) trees imported from Japan, and subisolates thereof, formed following experimental transmission by Agossypii, as well as those evolved through natural transmission by this aphid species in the groves. Symptoms of the naturally spread and the experimentally aphid-transmitted isolates were similar to those of the Satsuma CTV source isolates for all indicator plants except for sour orange (Citrus aurantium) and grapefruit (Citrus paradisi), with the aphid-transmitted isolates additionally inducing severe seedling yellows and stunting in these two indicators. Studies on the population heterogeneity of these isolates through comparison of their single-strand conformational polymorphism profiles and nucleotide sequences of the 25 kDa capsid protein gene from the predominant haplotypes, and dot-blot hybridization signals, revealed the presence of two major T36- and SY568- (or NUagA-) like genotypes along with a minor poorly characterized one in the originally infected Satsuma trees; in contrast, only a certain genomic variant having the highest similarity to the isolate SY568 (and NUagA) was predominant both in the naturally infected trees and in those infected experimentally by Agossypii. It seems that transmission by Agossypii to sweet orange (Citrus sinensis) has led to the preponderance of the CTV genomic variants inducing severe seedling yellows in northern Iran.  相似文献   
22.
The management of an Anterior Cruciate Ligament (ACL) avulsion is principally by surgery. There are two major techniques in this regard; fixation through open surgery (arthrotomy) or arthroscopically-assisted repair. These are not new in the literature; however, the debate regarding the better approach is still under debate. This study focused on comparing outcome and consequences of arthroscopically-assisted vs. open surgery in repairing ACL avulsion. In a randomized clinical trial, 44 patients with unilateral ACL avulsion were recruited in Tabriz Shohada teaching Centre during a 12 month period of time. These patients were randomized in two equal age and sex-matched groups underwent either arthroscopically-assisted or open ACL repair. The constructive technique was the same in both groups without using any graft. The minimum follow-up period was 6 months including 3 weeks, 3 months and 6 months postoperatively. Range of Motion (ROM), laxity, Anterior Drawer Test (ADT) result, duration of hospital stay, wound status, nonunion and return to previous work were compared between the two groups. Mean time of suture removal (p = 0.10), minimum and maximum ROM at months 3 (p = 0.43 and 0.22, respectively) and 6 (p = 0.73 and 0.77, respectively), ADT at months 3 and 6 (p = 0.16 for both), laxity at month 6 (p = 0.28) and wound status at week 3 (p = 0.35) were not significantly different between the two groups. There was no case of nonunion at month 6 in either group. The mean hospital stay was significantly shorter in the arthroscopy group (3.77 +/- 0.92 vs. 2.50 +/- 0.51 days; p < 0.001). The mean laxity score was significantly higher in the open surgery group at month 3 (4.82 +/- 0.59 vs. 4.45 +/- 0.60; p = 0.05). The rate of nonunion was significantly higher in the open surgery group at month 3 (40.9% vs. 9.1%; p = 0.02). Patients in the arthroscopically-assisted technique group returned sooner to previous work (17.41 +/- 1.53 vs. 14.82 +/- 0.96 weeks; p < 0.001). Based on our results, arthroscopically-assisted reconstruction of ACL avulsion is superior to open surgery.  相似文献   
23.
In the southwest of Iran over 130,000 ha of land are under sugarcane (Saccarum officinarum). In these sugarcane fields, about 400 kg ha?1 diamonium phosphate (DAP) and 400 kg ha?1 urea are applied annually. Four sugarcane growing sites were selected for this study: Haft-tapeh, Karoon, Shoeibieh and Ghazali with cultivation histories of 36, 20, 2 and 1 years, respectively. For each area, soil samples (0–30 cm) were taken from a transect of uncultivated, and both furrows and ridges of cultivated land. Electrical conductivity (EC), pH, clay, and calcium carbonate and organic carbon (OC) contents, Cl, Cd, Ni and Zn of 101 soil samples were measured. Cadmium profile distribution to a soil depth of 300 cm was determined, and the heavy metal concentrations in sugarcane and the associated soil samples of the three sugarcane sites were measured. The Cd and Ni contents among the sugarcane sites differed where Cd was related to clay content and Ni was related to OC content of soils. Cadmium content in sugarcane cultivated soil was lower compared to uncultivated soil even after years of application of P fertilizers. Nickel and Cd contents of sugarcane were much higher than levels in top soils but there was no significant relationship between Cd or Ni contents of sugarcane and soil chemical properties. The Zn content of soils decreased as either EC or Cl concentration of soils increased. There were no significant differences in Zn contents between different sugarcane sites and also between cultivated and uncultivated soils. Results also indicated that Cd was accumulated in bagasse and Ni was primarily accumulated in bagasse and molasses, but these heavy metals of white sugar were lower than the detectable values.  相似文献   
24.
To evaluate the effects of exploratory laparotomy on cellular and biochemical parameters of blood and peritoneal fluid, an experiment was conducted using 10 Iranian cross-bred male goats. Approximately 10 ml of blood and 1-1.5 ml of peritoneal fluid were collected from all animals prior to operation for estimation of control values. Exploratory laparotomy was performed under local analgesia. Blood and peritoneal fluid samples were collected at 24, 48, 72 and 96 h after exploratory laparotomy. The results revealed that after exploratory laparotomy, the number of white blood cells and the percentage and absolute number of neutrophils and band neutrophils significantly increased (P < 0.05). However, the percentage of lymphocytes decreased significantly (P < 0.05). The concentrations of blood urea nitrogen significantly increased (P < 0.05). Furthermore, following the operation, the percentage and absolute number of neutrophils in the peritoneal fluid significantly increased (P < 0.05). In contrast, the percentage of lymphocytes in the peritoneal fluid decreased significantly (P < 0.05). The concentration of protein in the peritoneal fluid increased significantly (P < 0.05).  相似文献   
25.
Characterization of Citrus tristeza virus isolates in northern Iran   总被引:1,自引:0,他引:1  
The biological and molecular properties of four Citrus tristeza virus (CTV) isolates isolated from infected Satsuma trees imported from Japan, and growing in citrus groves in northern Iran (Mahdasht orchards, Mazandaran Province), were investigated. CTV-infected samples were collected from sweet orange trees and grafted onto Alemow (Citrus macrophylla Wester) seedlings. On indicator plants, these isolates produced various symptoms including vein clearing and stem pitting on Mexican lime, Alemow, and Citrus hystrix, and yellowing and stunting on sour orange and grapefruit seedlings. Citrus samples were also surveyed for CTV using serological tests. The coat protein (CP) gene of these isolates was amplified using specific primers, yielding an amplicon of 672 bp for all isolates. Sequence analysis showed 98%–99% sequence homology of Iranian isolates with the Californian CTV severe stem-pitting isolate SY568 and 97%–98% homology with the Japanese seedling yellows isolate NUagA. The Iranian isolates were compared by restriction fragment length polymorphism (RFLP) analysis of the CP amplicon for further classification.  相似文献   
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Chlamydophila (C.) psittaci infections are highly prevalent in turkeys and the economical and public health importance of these infections has been recognized since 1950. As there are no vaccines, antibiotic treatment (tetracylines, enrofloxacine) is often needed to allow marketing of poultry. In this study, we explored the use of ovotransferrin (ovoTF), a natural anti-microbial protein, in preventing an experimental C. psittaci infection in specific pathogen free (SPF) turkeys. Turkeys were treated with aerosolized ovoTF prior to the infection. Groups 1 and 2 received a single dose of 10 and 5 mg ovoTF per turkey, respectively. Group 3 received a daily dose of 5mg ovoTF per turkey during 12 days. Group 4 served as untreated, infected control group. Turkeys were aerosol infected using 10(6) TCID(50) of the virulent C. psittaci serovar/genotype D strain 92/1293. Birds were monitored (clinical signs, bacterial excretion) during 12 subsequent days before being necropsied. At necropsy, pathology and C. psittaci replication in various tissues was examined. A single dose of 10mg ovoTF and a repeated daily dose of 5mg ovoTF could not prevent the birds from becoming infected with C. psittaci, but they significantly reduced the outcome of the infection. A single dose of 5mg ovoTF had no influence on the outcome of the infection as compared to the non-treated infected controls. Our results demonstrate the anti-chlamydial effect of ovoTF in vivo and present a base for further research on practical applications of ovoTF on turkey farms.  相似文献   
29.
Obstetrical Brachial Plexus Palsy (OBPP) is a complication of difficult delivery and resulted from excessive traction on the brachial plexus during delivery. Erb palsy, klumpke paralysis and panplexus palsy reported in 46, 0.6 and 20% of patients, respectively. Unilateral injury is more common than bilateral injury. Risk factors include macrosomia, multiparity, prior delivery of a child with OBPP, breech delivery shoulder dystocia, vacium and forceps assisted delivery and excessive maternal weight gain. The recovery rate is usually reported to be between 80 and 90%. We evaluated 42 children with OBPP. Out of them, we could follow only 28 cases during two years. Poor to moderate recovery occurred in 13 cases. Good to complete (expected) recovery occurred in 15 cases. Most of the patients were females. Right side palsy was more prevalent than left side palsy. Vaginal delivery without forceps was the most mode of delivery. Vertex was the most common presentation. Most of the patients were term. The mean weight of the birth was 3.8 kg. Erb palsy and pan-plexus palsy consisted of 71.4 and 28.6% of lesions. In patients with Erb palsy, there were preganglionic palsy in 3 (15.8%) and postganglionic palsy in 16 (84.2%) cases, while all the patients with panplexus palsy had postganglionic palsy. All patients with complete recovery (9 of 15) had Erb palsy and postganglionic lesion. Erb palsy was present in 71.4% and panplexus palsy was present in 28.6% of cases. Also, 23.8% of cases had preganglionic and 76.2% of cases had postganglionic injures.  相似文献   
30.
Soil compaction generally reduces crop performance because of degraded soil physical and biological properties, and possibly inappropriate soil nutritional status. The effects of varying compaction, and phosphorus (P) and zinc (Zn) supplies on the growth of Berseem or Egyptian clover (Trifolium alexandrimum), and accumulation of P and Zn in shoots and roots were investigated in a pot experiment using a surface layer of a Typic Torrifluvent (USDA), Calcaric Fluvisols (FAO) soil. Plants were treated with three soil compaction levels, three rates of P and three rates of Zn in a factorial combination. Phosphorus accumulation in shoots did not change up to bulk densities of 1.65 Mg m−3 and declined at bulk density of 1.80 Mg m−3. Increasing the levels of Zn and P resulted in a significant increase in shoot dry mass (from 0.3 to 0.8 g pot−1), and root length (from 11.4 to 32.5 m pot−1). Shoot and root growth were reduced by soil compaction particularly at low P and Zn application rates. Shoot dry mass was reduced from 0.8 to 0.3 g pot−1, and root length from 43 to 5 m pot−1 at bulk densities of 1.4 and 1.8 Mg m−3, respectively. However, the accumulation of P (from 0.06 to 0.15 g kg−1) and Zn per unit length of roots (from 0.8 to 1.8 μg pot−1) increased as soil compaction increased. As the Zn supply increased, Zn accumulation per unit length of roots, and total Zn accumulation increased. Severe compaction reduced P and Zn accumulation in shoots and also decreased shoot dry mass, and root length compared to lower soil compaction levels. The present study suggests that Zn and P supply can moderate the adverse effect of soil compaction on clover performance.  相似文献   
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