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A combination of light, scanning and transmission electron microscopy was used to investigate the morphology and ultrastructure of normal human spinal ligaments sampled from adult surgical specimens. The ligamenta flava consist mostly of dense elastic fibers, whereas the supraspinous and interspinous ligaments are preponderantly collagenous. In all ligaments, the collagen fascicles are characterized by a regular crimp structure. The inner collagen fibers of interspinous ligaments tend to be oriented parallel to the spinous processes while those of the peripheral layers run in postero-cranial direction. The presence of proteoglycan filaments is clearly demonstrated in all of the ligaments examined. They are mainly located at the d band of the collagen fibrils. These findings are discussed in relation to the function of the posterior ligamentous system. It is suggested that the interspinous ligaments are able to transmit tension from the thoracolumbar fascia to the spine. Finally, the spinal ligaments are thought to be involved in the control mechanism of the spine.  相似文献   
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Current medical approaches to control the Covid-19 pandemic are either to directly target the SARS-CoV-2 via innovate a defined drug and a safe vaccine or indirectly target the medical complications of the virus. One of the indirect strategies for fighting this virus has been mainly dependent on using anti‐inflammatory drugs to control cytokines storm responsible for severe health complications. We revealed the discovery of novel fused pyrrolopyrimidine derivatives as promising antioxidant and anti-inflammatory agents. The newly synthesised compounds were evaluated for their in vitro anti-inflammatory activity using RAW264.7 cells after stimulation with lipopolysaccharides (LPS). The results revealed that 3a, 4b, and 8e were the most potent analogues. Molecular docking and simulations of these compounds against COX-2, TLR-2 and TLR-4 respectively was performed. The former results were in line with the biological data and proved that 3a, 4b and 8e have potential antioxidant and anti-inflammatory effects.  相似文献   
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The purpose of this study was to assess whole blood selenium levels of 300 healthy adults living in four selected areas of the west of Algeria. Selenium was measured using differential pulse cathodic stripping voltammetry with a detection limit of 29.20 μg/L. The mean of whole blood selenium concentrations was 85.65 ± 21.60 μg/L ranging between 30.90 and 144.04 μg/L. This concentration did not vary significantly (P > 0.05) in relation to the gender of the subject, with concentrations of 87.75 ± 21.30 μg/L in men and 83.95 ± 21.60 μg/L in women group. Individuals older than 60 years had a whole blood selenium concentration significantly lower than the rest of the population. However, the measured selenium concentrations in the residential areas were not statistically different (P > 0.05). A total of 32 (10.70%) individuals exhibited whole blood selenium level below 60 μg/L. These results are similar to those of some European countries but are much lower than data observed in USA or seleniferous regions.  相似文献   
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Pathogenicity of eight Bacillus strains to seedlings of four cotton cultivars was evaluated under greenhouse conditions. Each of the tested cultivars was individually treated with powdered inoculum of each bacterial strain. Untreated seeds were planted as control treatments in autoclaved soil. Effects of the tested strains on levels and activities of some biochemical components of the infected seedlings were also assayed. The biochemical components included total soluble sugars, total soluble proteins, total free amino acids, peroxidase, polyphenol oxidase, phenols, and lipid peroxidation. ANOVA showed that Bacillus strain (B) was a very highly significant source of variation in damping-off and dry weight. Cotton cultivar (V) was a nonsignificant source of variation in damping-off while it was a significant source of variation in dry weight. B × V interaction was a significant source of variation in damping- off and a nonsignificant source of variation in dry weight. Bacillus strain was the most important source of variation as it accounted for 59.36 and 64.99% of the explained (model) variation in damping-off and dry weight, respectively. The lack of significant correlation between levels and activities of the assayed biochemical components and incidence of damping-off clearly demonstrated that these biochemical components were not involved in the pathogenicity of the tested strains. Therefore, it was hypothesized that the pathogenicity of the tested strains could be due to the effect of cell wall degrading enzymes of pathogenic toxins. Based on the results of the present study, Bacillus strains should be considered in studying the etiology of cotton seedling damping-off.  相似文献   
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Russian Journal of Bioorganic Chemistry - The aim of this work was to synthesize a diethyl phenylcarbamothioyl phosphonate (EThmP) and evaluate its biological activities. ThmP has been prepared...  相似文献   
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In 2004–05, during the December to February about 141 mango farmers were interviewed during peak activity of mango mealy bug in southern Punjab, Pakistan. The objective was to know the farmers’ knowledge, perceptions and practices in the management of mango mealy bug. Most of the farmers (94.33%) reported that Chaunsa variety (king of all mango varieties) was susceptible to mango and irrigation water was the major source of flare up of this pest. Basudin and Supracide were the most commonly used insecticides as 72.92 and 51.77 percent farmers gave positive response and grease bands were applied for the control of mango mealy bug by the majority of the respondents. Hundred percent yield losses was told by 22.7 percent respondents whereas 75 percent, 50 percent and 25 percent losses were reported by 39.7, 31.9 and 14.2 insecticidal spray did not show satisfaction to the respondents for the control of fertilized females of mango mealy bug coming down from the trees. Lack of knowledge about the pest, lack of money, adulterated and shortage of pesticides, lack of unity amongst farmers Further the growers’ views were tested in the field for confirmation and small land holdings were the main constraints for the control of mango mealy bug.  相似文献   
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ObjectivesBrain neoplasms or intracranial tumors, which are more common in older adults, can affect individuals of any age including pediatric and children. Exposure to carcinogenic agents including ionizing radiation and family history is one of the main causes of the disease. Early diagnosis is crucial to avoid prolonged. patients' suffering. The aim of the study was to efficiently recognize the brain tumors from the other brain tissues which include grey and white matter as well as cerebrospinal fluid (CSF).Materials and methodsThis study was performed using axial, sagittal and coronal views for fifty brain tumor patients randomly selected from a set of 200 patients, with a “control” set consisting of images showing no sign of disease; and the “test” brain MRI images for patients diagnosed with brain tumor. The study includes both genders with age ranging from 18 years to 83 years old, (56.5 ± 17.2). The brain images were acquired using a standard head coil Philips Intera 1.5 Tesla machine (USA). The thickness of each section in the entire sequence was 8 mm. Acquisition of T2-weighted and T1-weighted were performed. Interactive Data Language software was used to analyze the data.ResultsThe results of this study showed that: the overall accuracy of classification process was 94.8%, and for the tumor; the sensitivity was 97.3%. White matter and grey matter showed a classification accuracy of 95.7% and 89.7% and for CSF the accuracy was 94.3%.ConclusionThe results showed that brain tumor can be classified successfully and delineated using texture analysis with minimum efforts and with high accuracy for brain tumors.  相似文献   
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Seven culturable bacterial isolates, obtained from the internal stem tissues of Solanum elaeagnifolium and successfully colonizing the internal stem tissues of tomato cv. Rio Grande, were screened for their in vivo antifungal activity against Fusarium oxysporum f.sp. lycopersici (FOL) and their growth‐promoting potential on tomato plants. SV101 and SV104 isolates, assessed on pathogen‐challenged tomato plants led to a significant decrease (77–83%) in Fusarium wilt severity and vascular browning extent (76%), as compared to the inoculated and untreated control. Isolates enhanced growth parameters on pathogen‐challenged and unchallenged tomato plants. SV104 and SV101 isolates were most effective in suppressing disease and enhancing plant growth. These two isolates were identified as Bacillus sp. str. SV101 ( KU043040 ) and B. tequilensis str. SV104 ( KU976970 ). They displayed antifungal activity against FOL; pathogen growth was inhibited by 64% and an inhibition zone (11.50 and 19.75 mm) against FOL could be formed using whole cell suspensions. SV101 and SV104 extracellular metabolites also inhibited FOL growth by 20 and 55%, respectively, as compared to control. B. tequilensis str. SV104 was shown to produce protease, chitinase, pectinase, IAA and siderophores. Bacillus sp. str. SV101 displayed pectinase activity and was found to be an IAA‐producing and phosphate‐solubilizing agent. To our knowledge, this is the first study reporting on S. elaeagnifolium use as a potential source of potent biocontrol and plant growth‐promoting agents.  相似文献   
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