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241.
242.
The current study was designed to determine the changes of the cardiac troponin I (cTnI) expression in blood and tissue during the myocardial degeneration in calves with foot-and-mouth disease (FMD). Seventeen crossbred calves presenting pathological signs for FMD confirmed by viral analysis were studied. A biochemistry panel and immunohistochemistry were performed on 17 diseased calves and 7 calves used as controls. Creatine kinase (CK), CK-myocardial band (CK-MB), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) activities were analyzed for both groups. Cardiac troponin I levels were measured by a commercially available enzyme-linked immunosorbent assay kit. Mean cTnI (14.8 +/- 1.9 ng/ml) concentration and CK (573 +/- 407 U/l), CK-MB (238 +/- 37 U/l), AST (84 +/- 7), and LDH (298 +/- 29 U/l) activities were higher in FMD cases compared with controls. Immunohistochemistry revealed loss or depletion of cTnI expression in myocardium of all cases. None of the 7 controls showed loss of cTnI expression. Increased serum cTnI concentration correlated with myocardial injury and loss of cTnI immunolabeling in cardiomyocytes of calves with FMD.  相似文献   
243.
A pot experiment was conducted under growth chamber conditions to determine the lower and upper critical levels of boron (B) for plant growth, nodule development, and nodule acetylene reduction activity (ARA) in young soybean plants. Plants of a soybean cultivar, Tachinagaha, were grown in pots containing river sand to which a nutrient solution with different B levels was added and were inoculated with Bradyrhizobium japonicum A1017. At 8, 12, and 16 d after sowing (DAS), among the plants supplied with the solution at 0, 1.0, and 2.0 mg B L-1 , plants with 1.0 mg B L-1 showed the highest values for dry shoot and fresh root weight, root length, total number of developing nodules and meristematic nodules (DMN), and ARA. At 20 DAS plants grown with 11 B levels (0-2.0 mg L-1) were compared. The B critical deficiency levels for soybean dry shoot weight, fresh root weight, root length, DMN, number of complete nodules, and ARA were approximately 46, 35, 34, 57, 60, and 50 mg B kg-1 dry matter, and the critical toxicity levels were approximately 114, 137, 134, 97, 104, and 89 mg B kg-1 dry matter, respectively. The optimum B levels for the growth characters were approximately 34 to 137 mg B kg-1 dry matter. The optimum range of B levels for nodule formation and function was more restricted than that for the growth characters. Based on the results of treatments with various B concentrations, 0.4 mg B L-1 was found to be the concentration most beneficial for all the growth characters including nodule formation at the early stage (20 DAS) of development of soybean plants.  相似文献   
244.
Spinach (Spinacea oleracea L. cv. ‘Banarasi’), known to be responsive to potentially toxic elements, was investigated for chromium (Cr6 +) effect on iron metabolism and water relations. After 40 days growth in sand culture, a set of plants was supplied with 100 and 400 μM Cr6 + (potassium dichromate, K2Cr2O7), superimposed over the complete nutrient solution (control). Excess Cr6 + produced visual symptoms of toxicity and increased accumulation of Cr, more in roots than in leaves. Decreased concentration of chlorophylls and the activities of heme enzymes, catalase and peroxidase in excess Cr6 + may suggest interference of Cr in iron metabolism of plants. These changes associated with decrease in iron (Fe) accumulation in Cr6 + treated plants, indicate that by reducing absorption of Fe, Cr6 + impairs the Fe requiring steps of chlorophyll and heme biosynthesis. In spite of lower water saturation deficit, the leaves of Cr6 + treated plants showed a decrease in leaf water potential, associated with increase in diffusive resistance and lowering of transpiration rate along with proline accumulation indicates water stress. The changes observed in water stress parameters in Cr6 + treated plants indicate that excess supply of Cr6 + reduces the physiological availability of water.  相似文献   
245.
Abstract

Nitrogen (N) deficiency is a very common problem of alkaline soils. Incorporation of organic residues with urea could be promising practice for improving soil properties and crop yield. This study was aimed, to evaluate the responses of two maize cultivar (Azam and Jalal) to organic wastes and Urea (sole organic residues i.e. seed cake (SC), poultry manure (PM), press mud (PrM) and mineral nitrogen (urea) and their combinations with urea (25%, 50% or 75%) applied at 150?kg N ha?1 under field conditions. Significant differences were recorded for leaf area index, plant height, number of grains ear?1, 1000 grain weight, biological and grain yield to N sources. Maize cultivar Jalal performed significantly better than Azam for all tested traits. The performance of both cultivars was significantly better when N was applied as either SC/PM with urea at 25:75, SC and PM with urea at 25:25:50, 100% sole urea, SC/PrM with urea at 50:50, or all organic N sources (25%) with urea (75%). Integration of organic wastes with urea gave the higher maize yield however, it was similar to the yield obtained from sole urea but due to allied environmental and health hazards, the sole use of urea could not be encouraged.  相似文献   
246.
The peripheral effects of ω-conotoxins, selective blockers of N-type voltage-gated calcium channels (CaV2.2), have not been characterised across different clinically relevant pain models. This study examines the effects of locally administered ω-conotoxin MVIIA, GVIA, and CVIF on mechanical and thermal paw withdrawal threshold (PWT) in postsurgical pain (PSP), cisplatin-induced neuropathy (CisIPN), and oxaliplatin-induced neuropathy (OIPN) rodent models. Intraplantar injection of 300, 100 and 30 nM MVIIA significantly (p < 0.0001, p < 0.0001, and p < 0.05, respectively) alleviated mechanical allodynia of mice in PSP model compared to vehicle control group. Similarly, intraplantar injection of 300, 100, and 30 nM MVIIA (p < 0.0001, p < 0.01, and p < 0.05, respectively), and 300 nM and 100 nM GVIA (p < 0.0001 and p < 0.05, respectively) significantly increased mechanical thresholds of mice in OIPN model. The ED50 of GVIA and MVIIA in OIPN was found to be 1.8 pmol/paw and 0.8 pmol/paw, respectively. However, none of the ω-conotoxins were effective in a mouse model of CisIPN. The intraplantar administration of 300 nM GVIA, MVIIA, and CVIF did not cause any locomotor side effects. The intraplantar administration of MVIIA can alleviate incision-induced mechanical allodynia, and GVIA and MVIIA effectively reduce OIPN associated mechanical pain, without locomotor side effects, in rodent models. In contrast, CVIF was inactive in these pain models, suggesting it is unable to block a subset of N-type voltage-gated calcium channels associated with nociceptors in the skin.  相似文献   
247.
A 5-year-old, sexually intact poodle bitch was presented with a 2-year history of inguinal mass. A tentative diagnosis of hydrometra/mucometra with inguinal herniation was made and ovariohysterectomy with hernia repair was performed. Both fluid-filled uterine horns, both broad ligaments, and the uterine body were observed to be herniated through the inguinal ring. On histopathology, marked edema and diffuse hemorrhage were diagnosed in the uterus.  相似文献   
248.
Delamination is the most common failure mode in laminated composites, due to the reduced strength in the through-the-thickness direction. This paper describes the development of core-and-effect textured glass yarns for improving the bonding strength of laminated glass woven fabric composites. Air-jet texturing introduces bulk and loops in the yarn which provides more contact surface between the fibers and the resin. However, the yarn tenacity decreases after texturing because of the reduced alignment of the filaments. The effects of texturing air pressure, yarn overfeed ratio, yarn linear density and core-sheath ratio were studied in this paper. The tenacity of glass yarns decreased significantly after the texturing process. The reduction was smaller for yarns with a higher core linear density. The effects of texturing air pressure on the tenacity were found to be insignificant.  相似文献   
249.
250.
Asha KN  Chowdhury R  Hasan CM  Rashid MA 《Fitoterapia》2003,74(1-2):159-163
The extracts as well as piperolactum C, goniopedaline, 6beta-hydroxystigmasta-4,22-dien-3-one and a mixture of cis- and trans-4-hydroxymelleins obtained from Uvaria hamiltonii stem bark exhibited mild to moderate in vitro antibacterial activity. The results obtained were compared with a standard antibiotic, kanamycin. In a brine shrimp lethality bioassay the pet-ether, dichloromethane, methanol extracts and a major alkaloid, piperolactum C were found to exhibit mild to moderate cytotoxicity.  相似文献   
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