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31.
Methanol extract of Strychnos potatorum Linn. seeds (SPSE) was evaluated for its diuretic activity in Wistar albino rats. The SPSE was administered at the graded doses of 200, 400, and 600 mg/kg body weight. The parameters which were taken into account during the experimental on each rat were: total urine volume (corrected for water intake during the test period), body weight before and after the experiment, and the concentration of sodium, potassium, and chloride ions in urine. The total urine volumes of the SPSE (600 mg/kg)-treated rats were evaluated nearly two and half fold then compared with the control (saline treated) group. Excretion of cations (sodium and potassium ions) and anions (chloride ions) also increased significantly with respect to the control group. The diuretic effect was comparable with that of the standard drug Furosemide. The increase of cations in the urine on treatment with Strychnos potatorum seed extract (SPSE) was dose-dependent. This effect supports the use of the Strychnos potatorum seeds as a diuretic in folk remedies.  相似文献   
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We evaluated the relationship between pre-treatment positron emission tomography (PET) using the hypoxic tracer 18F-[2-(2-nitro-1-H-imidazol-1-yl)-N-(2,2,3,3,3- pentafluoropropyl) acetamide] (18F-EF5) and the response of preclinical tumor models to a range of fractionated radiotherapies. Subcutaneous HT29, A549 and RKO tumors grown in nude mice were imaged using 18F-EF5 positron emission tomography (PET) in order to characterize the extent and heterogeneity of hypoxia in these systems. Based on these results, 80 A549 tumors were subsequently grown and imaged using 18F-EF5 PET, and then treated with one, two, or four fraction radiation treatments to a total dose of 10–40 Gy. Response was monitored by serial caliper measurements of tumor volume. Longitudinal post-treatment 18F-EF5 PET imaging was performed on a subset of tumors. Terminal histologic analysis was performed to validate 18F-EF5 PET measures of hypoxia. EF5-positive tumors responded more poorly to low dose single fraction irradiation relative to EF5-negative tumors, however both groups responded similarly to larger single fraction doses. Irradiated tumors exhibited reduced 18F-EF5 uptake one month after treatment compared to control tumors. These findings indicate that pre- treatment 18F-EF5 PET can predict the response of tumors to single fraction radiation treatment. However, increasing the number of fractions delivered abrogates the difference in response between tumors with high and low EF5 uptake pre-treatment, in agreement with traditional radiobiology.  相似文献   
33.
Bacterial spot disease caused by Xanthomonas campestris pv. vesicatoria is one of the most important destructive diseases of tomato in many parts of the agricultural world. Therefore, the present study aims to determine the effects of Bacillus subtilis CBR05 inoculation on bacterial spot disease severity and the induction of defence-related enzymes response in tomato. Tomato leaves were evaluated to determine the activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and polyphenol oxidase (PPO)) and the content of malondialdehyde (MDA). A reduction in bacterial spot severity was observed in plants inoculated with B. subtilis, compared with those of uninoculated controls. A significant increase in SOD, CAT, POD, and PPO activities was observed in plants treated with B. subtilis after 24?h inoculation compared with non-inoculated pathogen control and mock-inoculated controls. Moreover, the MDA content was induced by pathogen infection, and its amount in B. subtilis inoculated plants was significantly lower than that in pathogen control. Our results suggest that early increases in antioxidant enzymes and the reduction in MDA content with B. subtilis inoculation may play a pivotal role in mitigating oxidative stress, thereby induced systemic resistance against bacterial spot disease in tomato.  相似文献   
34.
Applied Microbiology and Biotechnology - Alpha-mangostin (α-MG) has been reported to be an effective antibacterial agent against planktonic cells of many Gram-positive bacteria. However, the...  相似文献   
35.
Tagging biomedical entities such as gene, protein, cell, and cell-line is the first step and an important pre-requisite in biomedical literature mining. In this paper, we describe our hybrid named entity tagging approach namely BCC-NER (bidirectional, contextual clues named entity tagger for gene/protein mention recognition). BCC-NER is deployed with three modules. The first module is for text processing which includes basic NLP pre-processing, feature extraction, and feature selection. The second module is for training and model building with bidirectional conditional random fields (CRF) to parse the text in both directions (forward and backward) and integrate the backward and forward trained models using margin-infused relaxed algorithm (MIRA). The third and final module is for post-processing to achieve a better performance, which includes surrounding text features, parenthesis mismatching, and two-tier abbreviation algorithm. The evaluation results on BioCreative II GM test corpus of BCC-NER achieve a precision of 89.95, recall of 84.15 and overall F-score of 86.95, which is higher than the other currently available open source taggers.  相似文献   
36.
We have optimized conditions for efficient regeneration of the vegetatively propagated zoysia grass (Zoysia matrella L. Merr) cultivar “Konhee”. Two explants, young inflorescences, and stem nodes, were used and they displayed different responses to combinations and concentrations of plant growth regulators in callusing, embryogenic callus formation, and regeneration. The highest callus initiation rate from young inflorescences was obtained on medium supplemented with 4.5 to 9.0 μM 2,4-dicholorophenoxy acetic acid (2,4-D) and 0.44 μM 6-benzyl amino purine (BA). When the BA concentration was lowered to 0.044 μM, the highest percent embryogenic callus induction from young inflorescences was achieved. The highest callus initiation rate from stem nodes was obtained, when young inflorescences were cultured on MS medium supplemented with 4.5 to 9.0 μM 2,4-D, 0.44 μM BA, and 0.037 μM abscisic acid (ABA). But embryogenic callus formation from the stem node was highest in the presence of 4.5 to 9.0 μM 2,4-D, 0.044 μM BA, and 0.037 μM ABA. Addition of ABA significantly increased embryogenic callus formation from stem nodes, but not from young inflorescences. Regeneration percentage was variable in response to BA level, and inclusion of α-naphthalene acetic acid (NAA) and gibberellic acid (GA3) further increased the regeneration percentage. The highest regeneration percentages obtained from the young inflorescences and stem nodes were 82% and 67%, respectively. This is the first report showing that plants can be regenerated from young inflorescences and stem nodes of vegetatively propagated zoysia grass.  相似文献   
37.
Immune reconstitution inflammatory syndrome (IRIS) is an inflammatory manifestation that occurs subsequent to initiation of highly active antiretroviral therapy in terminal (HAART) HIV infection, mainly due to the restoration of robust immune responses directed against latent microbial antigens. IRIS is believed to be multifactorial and less studied. Herein, we postulate that hypothalamo-pituitary-adrenal (HPA) dysregulation, a well-documented manifestation in HIV/AIDS, could possibly disturb the balance between pro-inflammatory and anti-inflammatory cytokines leading to clinical IRIS. Drugs, opportunistic infections, stress and numerous intrinsic and extrinsic factors have been described to be the possible causes of IRIS in HIV illness.  相似文献   
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39.
Arsenic removal from groundwater by pretreated waste tea fungal biomass   总被引:11,自引:0,他引:11  
Arsenic contamination in ground water poses a serious threat on human health. The tea fungus, a waste produced during black tea fermentation has been examined for its capacity to sequester the metal ions from ground water samples. Autoclaved tea fungal mat and autoclaving followed by FeCl3 pretreated tea fungal mat were exploited for removal of As(III), As(V) and Fe(II) from ground water sample collected from Kolkata, West Bengal, India. The biosorption rate tends to increase with the increase in contact time and adsorbent dosage. FeCl3 pretreated and autoclaved fungal mats removed 100% of As(III) and Fe(II) after 30 min contact time and 77% of As(V) after 90 min contact time. The optimum adsorbent dosage was 1.0 g/50 mL of water sample. The results revealed that the FeCl3 pretreated fungal mat could be used as an effective biosorbent for As(III) and As(V); autoclaved fungal mat for Fe(II) removal from ground water sample.  相似文献   
40.
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