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81.
An intensive survey was conducted to identify virus diseases affecting pea crops in Tehran province of Iran. A total of 270 pea samples were collected randomly from pea fields. samples were tested by Double Antibody Sandwich Enzyme Linked Immunosorbent Assay (DAS-ELISA) using polyclonal antisera prepared against PSBMV (AS-0129, DSMZ, Braunschweig, Germany) and TSWV (AS-0580, DSMZ, Braunschweig, Germany). Virus disease incidence in pea samples was followed by PSBMV (33%) TSWV (24.4%) and PSBMV+TSWV (17.77). The positive samples with PSBMV were extracted in 0.05M phosphate buffer pH 6.5-7 containing 2% pvp and inoculated on Pisum sativum, Vicia faba, Chenopodium quinoa, Chenopodium amaranticolor. That produced in Pisum sativum; leaflets roll downwards, shoots curl, internodes shorten and plants are rosetted. Early infections reduce flower and fruit formation or eliminate their development. Broad bean has symptoms accompanied by a certain margin rolling and leaflet distortion. In Chenopodium amaranticolor necrotic local lesions and Chenopodium quinoa chlorotic local lesions had produced. The positive samples with TSWV were extracted in 0.01 M phosphate buffer containing 1% Na2 SO3 and inoculated on Petunia hybrida, Pisum sativum. TSWV causes several symptoms in infected peas, including brown leaf petiole and stem coloration, leaflet spotting, vein necrosis. In petunia hybrida after approximately 5 days showed local necrotic lesion. Biological purification in TSWV with chlorotic local lesions in Petunia hybrida and in PSBMV; chlorotic local lesions in Chenopodium quinoa were done. In PSBMV, back inoculated on Pisum sativum and Vicia faba also tested with DAS-ELISA. RT-PCR confirmed the results. This is the first report of PSBMV and TSWV naturally infecting pea in Iran.  相似文献   
82.
The cold-water extract from the skin of Opuntia ficus-indica fruits was fractionated by anion-exchange chromatography. The major fraction, which was purified by size exclusion chromatography, consisted of a polysaccharide composed of galactose and arabinose residues in the ratio 6.3:3.3, with traces of rhamnose, xylose and glucose, but no uronic acid. The results of methylation analysis, supported by (13)C NMR spectroscopy, indicated that this polysaccharide corresponded to an arabinogalactan having a backbone of (1-->4)-linked beta-D-galactopyranosyl residues with 39.5% of these units branched at O-3. The side-groups consisted either of single L-arabinofuranosyl units or L-arabinofuranosyl alpha-(1-->5)-linked disaccharides. This polysaccharide is thus an arabinogalactan that can be classified in the type I of the arabinogalactan family.  相似文献   
83.
Traumatic spinal cord injury (TSCI) is a condition with suffering of neural structures from acute trauma with short-term or permanent sensory and motor problems. This study was conducted with the aim of determining the prevalence of TSCI in Tehran with emphasis on demographic characteristics of patients and to evaluate the effect of computed tomography (CT) in determining fracture type and severity grade of injury among TSCI patients. In a cross-sectional study, all TSCI and spinal fracture patients (N = 520) who referred to the main trauma center in Tehran, Iran, in 2013 and 2014 were selected. Radiography and CT scan were prepared and reported blindedly by two radiologists. Majority of the patients was 21–30 years male, married and their most common occupation was car driver. A significant difference was observed between gender and etiology (P = 0.001). The main etiology was traffic accident followed by falling from height. While the most common location of injury for males was thoracic vertebrae followed by lumbar vertebrae; for females it was lumbar followed by thoracic. Majority of patients had ASIA (American Spinal Injury Association) impairment scale of E (normal), followed by B (sensory incomplete). Most of the cases were hospitalized less than one week. Age of the patient and duration of hospitalization had a significant association (P = 0.015). The results showed that in traumatic spinal cord events, traffic accident and falling from height are the main etiologies; hence, authorities in Iranian health system could consider preventive policies to decline the load and TSCI effects in hospitals and population.  相似文献   
84.
Origanum vulgare L is commonly known as a wild marjoram and winter sweet which has been used in the traditional medicine due to its therapeutic effects as stimulant, anticancer, antioxidant, antibacterial, anti-inflammatory and many other diseases. A reliable gene transfer system via Agrobacterium rhizogenes and plant regeneration via hairy roots was established in O. vulgare for the first time. The frequency of induced hairy roots was different by modification of the co-cultivation medium elements after infection by Agrobacterium rhizogenes strains K599 and ATCC15834. High transformation frequency (91.3 %) was achieved by co-cultivation of explants with A. rhizogenes on modified (MS) medium. The frequency of calli induction with an 81.5 % was achieved from hairy roots on MS medium with 0.25 mg/L?1 2,4-D. For shoot induction, initiated calli was transferred into a medium containing various concentrations of BA (0.1, 0.25, 0.5, 0.75 and 1 mg/L?1). The frequency of shoot generation (85.18 %) was achieved in medium fortified with 0.25 mg/L?1 of BA. Shoots were placed on MS medium with 0.25 mg/l IBA for root induction. Roots appeared and induction rate was achieved after 15 days.  相似文献   
85.
86.
In this research, biostratigraphy, microfacies analysis and sequence stratigraphic framework of the Asmari Formation are discussed at Sepidar Anticline, Interior Fars sub-Basin. The strata are Rupelian to Chattian in age. According to the distribution of benthic foraminifera, two assemblage zones were recognised (I-) Nummulites vascus–Nummulites fichteli and (II-) Archaias asmaricus/hensoni–Miogypsinoides complanatus. Eight microfacies types which can be grouped into three depositional environments are recognised. Distribution of Oligocene foraminifera together with other constituents allowed the identification of three third-order sequences at Asmari Formation. Correlation of analysed sections through Interior Fars sub-Basin represents the development of a carbonate ramp with a deepening trend from SE to NW along the Rupelian/Chattian boundary.  相似文献   
87.
Due to the limitations in the clinical application of embryonic stem cells (ESC) and induced pluripotent stem cells, mesenchymal stem cells (MSCs) are now much more interesting for cell-based therapy. Although MSCs have several advantages, they are not capable of differentiating to all three embryonic layers (three germ layers) without cultivation under specific induction media. Hence, improvement of MSCs for cell therapy purposes is under intensive study now. In this study, we isolated MSCs from umbilical cord tissue at the single-cell level, by treatment with trypsin, followed by cultivation under suspension conditions to form a colony. These colonies were trypsin resistant, capable of self-renewal differentiation to the three germ layers without any induction, and they were somewhat similar to ESC colonies. The cells were able to grow in both adherent and suspension culture conditions, expressed both the MSCs markers, especially CD105, and the multipotency markers, i.e., SSEA-3, and had a limited lifespan. The cells were expanded under simple culture conditions at the single-cell level and were homogenous. Further and complementary studies are required to understand how trypsin-tolerant mesenchymal stem cells are established. However, our study suggested non-embryonic resources for future cell-based therapy.  相似文献   
88.
A halophilic archaeon, Halorubrum sp. strain Ha25, produced extracellular halophilic organic solvent-tolerant amylopullulanase. The maximum enzyme production was at high salt concentration, 3–4 M NaCl. Optimum pH and temperature for enzyme production were 7.0 and 40 °C, respectively. Molecular mass of purified enzyme was estimated to be about 140 kDa by SDS–PAGE. This enzyme was active on pullulan and starch as substrates. The apparent K m for the enzyme activity on pullulan was 4 mg/ml and for soluble starch was 1.8 mg/ml. Optimum temperature for amylolytic and pullulytic activities was 50 °C. Optimum pH for amylolytic activity was 7 and for pullulytic activity was 7.5. This enzyme was active over a wide range of concentrations (0–4.5 M) of NaCl. The effect of organic solvents on the enzyme activities showed that this enzyme was more stable in the presence of non-polar organic solvents than polar solvents. This study is the first report on amylopullulanase production in halophilic bacteria and archaea.  相似文献   
89.
Pseudomonas aeruginosa as an opportunistic pathogen causes lethal infections in immunocompromised individuals. This bacterium possesses a polar flagellum made up of flagellin subunits. Flagella have important roles in motility, chemotaxis, and establishment of P. aeruginosa in acute phase of infections. Isolation, cloning, and expression of flagellin were aimed at in this study. Flagellin gene (fliC) of P. aeruginosa strain 8821M was isolated by PCR and cloned into a pET expression vector. The recombinant flagellin (46 kDa) was overexpressed as inclusion bodies (IBs). IBs were solubilized in guanidine hydrochloride (GuHCl) followed by affinity-purification and renatured using Ni2+-Sepharose resin. Recombinant flagellins reacted with the serum from a rabbit previously immunized with native flagellin. In addition, polyclonal antiserum raised against the recombinant flagellin was shown to significantly inhibit the cell motility of P. aeruginosa strain 8821M in vitro.  相似文献   
90.
PKR, an interferon-induced double-stranded RNA activated serine-threonine kinase, is a component of signal transduction pathways mediating cell growth control and responses to stress and viral infection. Analysis of separate PKR functional domains by NMR and X-ray crystallography has revealed details of PKR RNA binding domains and kinase domain, respectively. Here, we report the structural characteristics, calculated from biochemical and neutron scattering data, of a native PKR fraction with a high level of autophosphorylation and constitutive kinase activity. The experiments reveal association of the protein monomer into dimers and tetramers, in the absence of double-stranded RNA or other activators. Low-resolution structures of the association states were obtained from the large angle neutron scattering data and reveal the relative orientation of all protein domains in the activated kinase dimer. Low-resolution structures were also obtained for a PKR tetramer-monoclonal antibody complex. Taken together, this information leads to a new model for the structure of the functioning unit of the enzyme, highlights the flexibility of PKR and sheds light on the mechanism of PKR activation. The results of this study emphasize the usefulness of low-resolution structural studies in solution on large flexible multiple domain proteins.  相似文献   
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