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61.
Natural materials and plants have a long history of medical applications due to their broad range of favorable biological functions including biocompatibility, anti-bacterial, anti-oxidant and anti-inflammatory properties. Main objective of this study was to develop alginate-chitosan-hyaluronic acid (ACH) composite fibers with controlled drug release, and liquid retention properties for better moist wound healing. The dope comprising sodium alginate was extruded into calcium chloride (CaC12) coagulation bath. The developed calcium alginate fibers were then passed through a bath containing hydrolyzed chitosan and dip coated with hyaluronic acid for 24 hours. The resulting ACH composite fibers were then rinsed with deionized water and dried using acetone. These fibers were tested for tensile properties, % swelling, liquid absorption (g/g) and controlled drug release. The results concluded that ACH composite fibers can be produced by wet spinning and have adequate tensile properties, high % swelling, liquid absorption (g/g) and controlled release of hyaluronic acid for improved wound healing.  相似文献   
62.
The objective was to study the growth potential of Sahiwal calves given milk or milk replacer with or without concentrates. For this purpose, forty-eight Sahiwal calves were divided into four groups of 12 animals each with equal sex ratio. In each group, the calves were offered either milk or a milk replacer (MR) at a rate of 10% of their body weight adjusted weekly. In addition to this, calves were fed either a starter ration plus Egyptian clover hay (SR + H) or hay only (H) until the end of trial. The milk or MR was withdrawn gradually from day 56 until animals were weaned completely by day 84. Calves offered milk grew faster than those offered MR (357 ± 9 vs. 162 ± 9 g/day; p < 0.05) and displayed higher weaning weights (51.6 ± 0.8 vs. 35.2 ± 0.8 kg; p < 0.05). The calves offered SR + H grew faster (311 ± 9 vs. 208 ± 9 g/day; p < 0.05) and displayed higher weaning weights (48.7 ± 0.8 vs. 38.1 ± 0.8 kg; p < 0.05) than those fed H alone. Calves offered milk plus SR + H showed the highest growth rate and weaning weights (401 ± 13 g/day and 56.3 ± 1 kg, respectively). The lowest growth rate and weaning weights were observed in calves offered MR and H only (115 ± 13 g/day and 30.3 ± 1 kg, respectively). Calves offered the MR had higher number of scour days than those offered milk (13.5 vs. 3.3). The feeding of whole milk in combination with the starter ration and hay resulted in superior growth rates, higher weaning weights, and healthier calves than the other feeding regimens.  相似文献   
63.
In order to identify the parasitoids of Phyllocnistis citrella, an important pest of Citrus, the larvae and pupae of this pest were collected from Citrus reticulata Blanco orchards in the Sargodha region of Pakistan. The parasitoid species were identified, and their abundance was recorded. A total of two species were identified: Citrostichus phyllocnistoides (Narayan) (Hymenoptera: Eulophidae) and Cirrospilus ingenuus Gahan (Hymenoptera: Eulophidae). Out of a total of 409 P. citrella larvae and pupae collected, 73 Cphyllocnistoides and 39 Cingenuus adults emerged. This paper documents the species and the abundance of the parasitoids associated with P. citrella in the Sargodha region of Pakistan.  相似文献   
64.
Journal of Plant Diseases and Protection - Entomopathogenic nematodes symbiotically associated with Photorhabdus spp. invade the larvae of susceptible insects and Photorhabdus bacteria are released...  相似文献   
65.
The accumulation of total soluble and cell wall-bound phenolics and total soluble proteins in Zea mays plants exposed to drought stress and foliar spray of salicylic acid (SA) at 10?4?mol/L and 10?5?mol/L was investigated. Drought stress was imposed at the four-leaf stage for 10 days (30–35% field capacity). Dehydration of maize leaves was accompanied by the accumulation of both total soluble and cell wall-bound phenolics, reduction in leaf relative water content (LRWC), and shoot and root growth attributes. Foliar spraying of SA further augmented the content of total soluble and cell wall-bound phenolics and total soluble proteins content under drought stress. SA ameliorated the adverse effects of drought stress on LRWC, shoot fresh weight, shoot dry weight, root fresh weight, root dry weight, root length and root area. The accumulation of both soluble and cell wall-bound phenolics by foliar spray of SA may be a mechanism related to SA-induced drought stress tolerance in maize. It was concluded that foliar spraying of SA at 10?5?mol/L can be highly economical and effective for modifying the effects of drought stress on maize at the four-leaf stage.  相似文献   
66.
Soil salinity is becoming a major problem due to a variety of natural and man-caused factors particularly in arid areas. The present study documented on the effect of nephthyl acetic acid (NAA) foliar spray on physiological attributes of maize including growth responses, osmolites, and antioxidant enzymatic activities of the selected maize varieties PSEV3-2(ES) and Sarhad yellow at vegetative stage exposed to different sodium chloride (NaCl) concentrations of 20mM to 100mM, through pot experiments. Osmolites and antioxidant enzymes serve as physiological markers for selected maize varieties under saline conditions. The maximum increase in osmolites and protein contents, Peroxidases (EC 1.11.1.x), Superoxide dismutase (EC 1.15.1.1), Catalse (EC 1.11.1.6) and Ascorbate peroxidase (EC 1.11.1.11) activities in Sarhad yellow indicating the tolerance level of this variety as compare to PSEV3-2(ES). It has been concluded that the reduction in growth responses due to salinity has been improved by the exogenous application of nephthyl acetic acid.  相似文献   
67.
Fungal phytases belonging to "histidine acid phosphatase" or HAP class of phosphohydrolases that catalyze the hydrolysis of phytic acid could also hydrolyze O-phospho-L-tyrosine, which is also called phosphotyrosine. Two phytases from Aspergillus niger and Aspergillus awamori with pH optima 2.5 were tested for phosphotyrosine hydrolase activity; both enzymes cleaved the phosphomonoester bond of phosphotyrosine efficiently at acidic pH. The Km for phosphotyrosine ranged from 465 to 590 microM as opposed to 135 to 160 microM for phytate. The Vmax, however, is 2-4 times higher for phosphotyrosine than it is for phytate. The catalytic efficiency of phytase for phosphotyrosine is on the same order as it is for phytate (3.5 x 10(6) to 1.6 x 10(7) M(-1) s(-1)); the pH versus activity profile for phosphotyrosine is, however, different from what it is for phytate. The temperature optima shifted 5 degrees C higher to 70 degrees C when phosphotyrosine was used as the substrate. Taken together, the kinetic data show that fungal HAPs that are known as PhyB are capable of cleaving the phosphomonoester bond in phosphotyrosine. This is the first time that phosphotyrosine phosphatase (PTPase) activity has been reported for the subgroup of HAP known as phytase.  相似文献   
68.
Conservational tillage (CT) in combination with broad spectrum herbicide may be more efficient and economical in controlling weeds,reducing cost of cultivation,and enhancing wheat yield.Field experimen...  相似文献   
69.
This study investigated the effect of credit constraints and credit unconstraints on the technical efficiency of hybrid maize growers in the Khyber Pakhtunkhwa Province(KPK) of Pakistan. The primary data were collected by a direct elicitation method from 510 maize growers of KPK Province. Stochastic frontier model techniques were used for technical efficiency analyses. The results revealed that the mean technical efficiency difference between the two groups was 10.2%. The results of technical inefficiency effect modeling demonstrated that education of the household head, family size, number of married family members, off-farm income, farming experience, tractor drill, water irrigation through a lined course, certified seed, extension services, household saving variables, and a credit size variable had positive effects on technical efficiency for both credit constrained farmers(CCFs) and credit unconstrained farmers(UCCFs). In addition, age of household head and fragmented land values had negative effects on technical efficiency for both groups. However, the interest rate had positive and negative impacts on the technical efficiency of CCFs and UCCFs, respectively. Our results have significant implications for policies related to land use, interest rate, and banking sector expansion in the rural areas of Pakistan.  相似文献   
70.

The study aimed to investigate if vegetable-based high-energy mash diets supplemented with NaHCO3, l-arginine?+?vitamin C, and vegetable oils were effective against tachycardia and polycythemia in the broiler chicken. A total of 256 Ross-308 day-old male broiler chicks were randomly distributed into eight dietary treatment groups in a three-way ANOVA with 2?×?2?×?2 factorial arrangement (three factors, i.e., NaHCO3, l-arginine?+?vitamin C, and vegetable oil each with two levels, e.g., 0 and 0.1% of NaHCO3 and l-arginine?+?vitamin C; 3 and 4% of vegetable oil supplemented with basal diet) for a period of 35 days. Iso-caloric and iso-nitrogenous diets were formulated and supplied ad libitum. The final live weight (FLW), average daily feed intake (ADFI), average daily gain (ADG), feed efficiency (FE), carcass traits, cardio-pulmonary morphometry, total protein (TP), hemoglobin (Hb), triiodothyronine (T3), incidence of tachycardia, and polycythemia were examined. Supplementation of NaHCO3 increased 2.2% ADFI, 5.5% FE, and 23.2% TP. The l-arginine?+?vitamin C increased 2.4% FLW and decreased 1.9% heart rate. Vegetable oil increased 1.3% ADFI, 4.2% ADG, 8.6% FE, 23.1% Hb, and 15.5% PCV. The NaHCO3, l-arginine?+?vitamin C, and vegetable oil additively interacted to increase 31.5% T3 at the expense of 21.1% of the weight of the right ventricle (RV). The RV:TV, carcass traits, and hemato-biochemical indices remained within normal range irrespective of the levels of the supplementations of the test ingredients. It was concluded that vegetable-based high-energy mash diets were not susceptible to tachycardia and polycythemia. The addition of NaHCO3 and l-arginine?+?vitamin C ameliorated the propensity of tachycardia and polycythemia without deteriorating performance, carcass traits, and hemato-biochemical indices of the broiler chicken in a dose-dependent manner.

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