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41.
The present study was conducted to compare the effects of xenogenic bovine fetal demineralized bone matrix (DBM), commercial DBM, omentum, omentum-calf fetal DBM, cortical autograft and xenogenic cartilage powder on the healing of tibial defects in a dog model to determine the best material for bone healing. Seven male adult mongrel dogs, weighing 26.2 ± 2.5 kg, were used in this study. Seven holes with a diameter of 4-mm were created and then filled with several biomaterials. Radiographs were taken postoperatively on day 1 and weeks 2, 4, 6, 8. The operated tibias were removed on the 56th postoperative day and histopathologically evaluated. On postoperative days 14, 42 and 56, the lesions of the control group were significantly inferior to those in the other group (p < 0.05). On the 28th postoperative day, the autograft group was significantly superior to the control and omentum groups (p < 0.05). Moreover, calf fetal DBM was significantly superior to the control group. There was no significant difference between the histopathological sections of all groups. Overall, the omentum and omentum-DBM groups were superior to the control group, but inferior to the autograft, commercial-DBM, calf fetal DBM and calf fetal cartilage groups.  相似文献   
42.
43.
Cr3+ sorption on strong acid exchanger Amberlyst-15(H+) is studied as a function of time and temperature using CrCl3.6H2O and [Cr4(SO4)5(OH)2] solutions. The rate is found to be governed by a mixed diffusion for both the solutions and faster for Cl1? solution than SO4 2?. The exchange capacities are found to be higher for Cl1? system than SO4 2?. From the rate constant values, the energies of activation are calculated using the well-known Arrhenius equation. Equilibrium data is explained with the help of the Langmuir equation. The Langmuir parameters are also found to be higher for exchange from the chloride solutions. Various thermodynamic parameters (??Ho, ??So, and ??Go) for Cr3+ exchange on the resin are calculated. The ??Go values are found to be negative while ??Ho and ??So are positive for both the Cr3+/Cl1? and Cr3+/SO4 2? systems. It is suggested that in case of Cl1? solutions, the metal is exchanged as Cr3+, while in case of SO4 2? solutions, the metal exchanging specie is CrSO4 +.  相似文献   
44.
Abstract In an attempt to identify appropriate feeding rates for multispecies of fish raised in fertilized earthen ponds, the present work was conducted over a 19‐week experimental period to establish the growth performance, production and body composition of Nile tilapia, common carp and silver carp fed 0.0%, 0.5%, 1.0%, 3.0%, 5.0% biomass and to apparent satiation (treatments). Twelve ponds were stocked with a similar number and weight of each fish species. Two ponds were assigned to each of the treatments, and a 25% protein pelleted fish feed was used to feed fish at the specified rate of feeding. At the end of the experiment, growth, weight gain, survival, yield and body composition of fish groups were affected by the treatments. The economic effectiveness also varied among treatments. The most conspicuous attribute of the feeding rates was its lack of influence on growth (g day?1), weight gain (g per fish), yield (kg ha?1) or body composition of silver carp. The results of whole‐body proximate analysis indicated that various feeding rates had either an irregular pattern or no effects on the protein and ash gain per 100 g of fish body weight (bw) gain. The most notable exceptions were significant (P < 0.05) increases in body fat and gross energy gains in Nile tilapia, common carp and silver carp accompanied by decreases in percentages of moisture (but not in silver carp) as feeding rate increased. Among the six different feeding levels, feeding to apparent satiation (feed amount was equivalent to 2.67% of fish bw day?1) appeared to be optimal, as it significantly (P < 0.05) supported the highest fish production, income and net profit compared with all other treatments except for the 3% feeding level, for which the differences in those measurements were comparable.  相似文献   
45.
正常稳定的瘤胃微生物区系是反刍动物瘤胃健康的重要指标,且在瘤胃结构形态发育、微生物定植模式、免疫功能调节及抵御外源致病因子侵袭等方面发挥着重要积极作用.最近研究表明,新生反刍动物瘤胃微生物组成相对单一,但随着早期瘤胃发育过程中不同微生物群落相继开始定植并占据不同的生态位,此时的营养干预可能会形成特定的微生物群落组合并产...  相似文献   
46.
In cereals, chromosome doubling of microspore-derived haploid plants is a critical step in producing doubled haploid plants. This investigation was undertaken to study the effect of incorporation of colchicine in the induction medium for anther culture, and the effect of colchicine on anther culture-derived plants of triticale grown under controlled greenhouse conditions. In the latter case, chromosome doubling of adult sterile plants derived from anther culture of fourteen triticale populations was attempted, where androgenetic plants with non-dehiscent anthers were cloned and subjected to the colchicine treatment, and then grown with the aid of hydroponics. The hydroponic system provided optimal conditions for recovery of the affected haploids from the toxic effects of colchicine treatment and all colchicine-treated plants survived. A topcross-F1 (TC1F1) population with timopheevii cytoplasm produced the highest percentage of plants with seed-set either due to chromosome doubling by colchicine (98%) or spontaneous doubling of chromosome number (15%). Colchicine-treated anthers performed inferior than control in both induction and regeneration phases. One of the key observation of this study was the reversal from reproductive stage back to the vegetative stage which in turn enabled further cloning of haploid plants under hydroponic conditions once they were identified as sterile. The one hundred percent survival rate of in vitro-derived plants, 100% survival rate of colchicine treated haploid plants and the high chromosome doubling success rate (X = 82.3) observed in this study imply that a temperature-controlled greenhouse with an hydroponic system provides an efficient environment for inducing chromosome doubling of haploid plants in cereals. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
47.

Bluetongue virus (BTV), a member of Orbivirus genus (family Reoviridae), is a non-contagious infection of domestic and wild ruminants. The current study was designed to detect various serotypes of BTV in small ruminants of Khyber Pakhtunkhwa (KPK) province of Pakistan, along with their effects on hemato-biochemical parameters. A total of 408 serum samples in four districts (Mansehra, Abbottabad, Swabi, and Kohat) of KPK from small ruminants were screened based on competitive ELISA (cELISA). A total of 204 (50%) samples were found positive for BTV group–specific antibodies. The seropositive samples were processed for the detection of BTV serotypes through real-time polymerase chain reaction (qPCR). Out of 204 cELISA-positive samples, 60 (29.41%) were found positive through qPCR. Three serotypes [6, 8, 9] were detected from Mansehra District and two from Kohat [2, 8] and Abbottabad [6, 8], while only one from Swabi [8]. The serotype “8” was found consistently in all the four study districts. A significant (p?<?0.05) increase in the level of blood urea nitrogen (BUN) and alkaline phosphatase (ALP) was recorded in goats, whereas aspartate aminotransferase (AST) in sheep infected with BTV, compared to healthy animals. The hematological parameters showed significantly (p?<?0.05) raised total leucocyte count (TLC) in both sheep and goats, whereas only hematocrit (HCT) value was increased significantly (p?<?0.05) in infected sheep. This is the first report on serotyping of BTV among small ruminants in Pakistan.

  相似文献   
48.
Zizyphus oxyphylla Edgew is used in Pakistan as a folk medicinal remedy for inflammatory conditions, pains especially rheumatic pain, fevers, allergy and diabetes. The aim of the current study was to scientifically validate the folk use of Z. oxyphylla Edgew by using the isolated compound in vitro and in vivo levels. Kushecarpin A was isolated from ethyl acetate fraction of the plant crude extract. Molecular docking simulations predicted Kushecarpin A as a potential new lipoxygenase (LOX) inhibitor. Kushecarpin A showed significant lipoxygenase inhibition (IC50: 7.2 ± 0.02 μM) thus validated computational prediction. It also exhibited significant and highly significant inhibition (p < 0.05 and p < 0.01) of carrageenan-induced hind paw oedema at the doses of 5, 10 and 20 mg/kg. Kushecarpin A seems to be a potentially new anti-inflammatory compound responsible for anti-inflammatory activities of Z. oxyphylla Edgew. In vitro and in vivo anti-inflammatory inflammatory activities were found in good agreement with the folk medicinal use of Z. oxyphylla Edgew in inflammatory disorders.  相似文献   
49.
In recent years, flexible, mechanically strong and environmental friendly thermal insulation materials have attracted considerable attention. In this work, silica aerogel/polyethylene terephthalate (PET) nonwoven fiber composite with desirable characteristics was prepared via a two-step sol-gel process followed by an ambient drying method through immersing the PET nonwoven fiber into silica sol. The silica aerogel particles were characterized by FTIR, FE-SEM, TGA and nitrogen adsorption analysis. The morphology and hydrophobic properties of neat PET nonwoven fiber and its silica aerogel composite were also investigated. For studying thermal protective properties, the thermal diffusivity was calculated from temperature distribution curves. The mean pore size of 11 nm, the surface area of 606 m2/g and the total pore volume of 1.77 cm3/g for the silica aerogel particles in the composite are obtained from nitrogen adsorption analysis, indicating the aerogel can maintain its high porosity in the nonwoven composite structure. Silica aerogel particles were efficiently covered the surface of the PET fibers and completely filled the micron size pores of the nonwoven fiber leading to a stronger hydrophobicity and higher thermal insulation performance in the aerogel composite samples compared to the neat PET nonwoven. In this regard, an almost 64 % decrease in the thermal diffusivity was achieved with 66 wt% silica aerogel.  相似文献   
50.
Transgenic cotton carrying the CrylAc gene has revolutionized insect pest control since its adoption,although the development of resistance in insect pests has reduced its efficacy.After 10 years of cultivating Bacillus thuringiensis(Bt) cotton with a single Cry1 Ac gene,growers are on the verge of adopting Bt cotton that carries the double gene(Cry1 Ac+Cry2 A) due to its better effectiveness against insect pests.Thus,the current study was designed to evaluate the role of each gene in the effect...  相似文献   
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