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1.

Background, aim, and scope  

Plant growth and productivity under abiotic stresses such as water shortage or pollution are major problems which currently worry scientists in the field of food production and plant health. Since the intensification of livestock production with its associated increased demand for fodder has encouraged farmers to rely more heavily on chemical fertilizers, very often, municipal waste and wastewater sludge is considered a possible source of plant nutrients, although it might carry a significant amount of anthropogeneous pollutants. The extent to which plants react to drought, as well as how pollutants are taken up or how they act on plants, might depend on rhizosphere processes such as mycorrhizal symbioses. Therefore, it seemed timely to investigate plant defense reactions in the presence of arbuscular mycorrhizal fungi (AMF) toward a possible dangerous sewage sludge pollutant under the influence of drought.  相似文献   
2.
Background: Bone tissue engineering requires materials that are biocompatible, mechanically suited for bone function, integrated with the host skeleton, and support osteoinduction of the implanted cells for new bone formation. The aim of this study was to compare the osteogenic potential of xenograft with hydroxyapatite/β- tricalcium phosphate (HA/β-TCP) scaffold. Methods: New Zealand rabbits (n = 9) were divided into 3 groups. Osteoblast cells were originally isolated from rabbit iliac crest and cultured in DMEM/F12. After creating a critical-sized defect (2 × 3 cm) in rabbit tibia bone, the defect was filled with an implant of HA/TCP with osteoblasts and xenograft in the hole of left (as control) and right tibia, respectively. The new bone formation and the development of bone union within the defect were evaluated by x-ray images and eosine and hematoxylin staining at 4, 8, and 12 weeks post-operation. Results: The bone partially formed in both groups was filled with osteoblast cultured on porous implants at 4 weeks. Over time, progressive bone regeneration was observed inside the pores. Moreover, a progressive vascular ingrowth and progressive integration with the host bone were obvious in xenograft when compared to HA/β-TCP. A good integration between the xenograft implants and the bone was observed radiographically and confirmed by histological section. Conclusion: The result showed that the bone defect can be repaired using both synthetic and xenograft implants. However, the xenograft showed a better osteointegration as compared to HA/β-TCP scaffold.Key Words: Osteoblasts, Hydroxyapatite/β-Tricalcium phosphate (TCP), Bone tissue  相似文献   
3.
Abstract

Using mineral nutrients is recommended as a plan to alleviate or avoid spring frost damage to blossoms. The purpose of this study was to investigate the effects of potassium application on reducing or preventing spring frost damage of almond (Prunus dulcis Mill.) flowers. Treatments were four levels of K2SO4 (0, 1, 2, and 4%). The nutrition solutions were sprayed on trees in two times (bud swell stage and green tip stage) in 2018–2019. The spurs containing flower buds were collected during the full blooming phase. The spurs segments were exposed to three different freeze test temperatures (0, ?2, and ?4?°C), and some relevant physiochemical changes were evaluated. The application of K2SO4, especially 4% K2SO4, decreased freezing injury, electrolyte leakage percentage, hydrogen peroxide (H2O2), and malondialdehyde (MDA) concentrations of flowers after freezing tests compared with control. The nutrient treatments, especially 4% K2SO4, increased significantly the contents of soluble proteins, soluble carbohydrates, total phenolic compounds, and proline of flowers. The results of the present study could have implications for the use of potassium in freezing tolerance improvement of other temperate fruit trees grown in low temperatures regions.  相似文献   
4.
We investigated the effects of concentration of the microalga Dunaliella tertiolecta on the growth and survival of fairy shrimp, Phallocryptus spinosa. Newly hatched nauplii were stocked into containers, maintained at different concentrations of D. tertiolecta (at 18, 36, 54, 72 and 90 × 106 cells mL?1). All treatments were in quadruplicate and each replicate was stocked with 100 larvae in a 2‐L cylindrical bowl. We studied the survival and growth of the fairy shrimp after 3, 6, 9, 12 and 15 days of culture. The results indicated significant differences, in terms of growth and survival, of fairy shrimps fed at different algal densities. The highest and lowest growth and survival among the treatments were observed on Day 15, the highest in animals fed at a concentration of 90 × 106 cells mL?1 and the lowest in animals fed at a concentration of 18 × 106 cells mL?1. We conclude that the growth and survival of the P. spinosa increased with increasing density of algae, to a threshold level. Within certain concentration limits, the addition of D. tertiolecta substantially improved the performance of larval culture of P. spinosa, suggesting that this fairy shrimp has potential in terms of aquaculture development.  相似文献   
5.
The management of an Anterior Cruciate Ligament (ACL) avulsion is principally by surgery. There are two major techniques in this regard; fixation through open surgery (arthrotomy) or arthroscopically-assisted repair. These are not new in the literature; however, the debate regarding the better approach is still under debate. This study focused on comparing outcome and consequences of arthroscopically-assisted vs. open surgery in repairing ACL avulsion. In a randomized clinical trial, 44 patients with unilateral ACL avulsion were recruited in Tabriz Shohada teaching Centre during a 12 month period of time. These patients were randomized in two equal age and sex-matched groups underwent either arthroscopically-assisted or open ACL repair. The constructive technique was the same in both groups without using any graft. The minimum follow-up period was 6 months including 3 weeks, 3 months and 6 months postoperatively. Range of Motion (ROM), laxity, Anterior Drawer Test (ADT) result, duration of hospital stay, wound status, nonunion and return to previous work were compared between the two groups. Mean time of suture removal (p = 0.10), minimum and maximum ROM at months 3 (p = 0.43 and 0.22, respectively) and 6 (p = 0.73 and 0.77, respectively), ADT at months 3 and 6 (p = 0.16 for both), laxity at month 6 (p = 0.28) and wound status at week 3 (p = 0.35) were not significantly different between the two groups. There was no case of nonunion at month 6 in either group. The mean hospital stay was significantly shorter in the arthroscopy group (3.77 +/- 0.92 vs. 2.50 +/- 0.51 days; p < 0.001). The mean laxity score was significantly higher in the open surgery group at month 3 (4.82 +/- 0.59 vs. 4.45 +/- 0.60; p = 0.05). The rate of nonunion was significantly higher in the open surgery group at month 3 (40.9% vs. 9.1%; p = 0.02). Patients in the arthroscopically-assisted technique group returned sooner to previous work (17.41 +/- 1.53 vs. 14.82 +/- 0.96 weeks; p < 0.001). Based on our results, arthroscopically-assisted reconstruction of ACL avulsion is superior to open surgery.  相似文献   
6.
Transversal variations of some ultrasound wave parameters (phase velocity, group velocity, attenuation coefficient and acoustic radiation) were measured from the pith to the bark of poplar tension wood discs in different orthotropic directions. Over 80 cubic specimens of 2 × 2 × 10 cm3 (radial, tangential and longitudinal, respectively) were prepared and tested acoustically. Samples containing tension woods were separated from normal ones using anatomical experiments. Results showed acoustical behaviour of normal and tension wood improved in longitudinal direction while the distance between pith and bark increased; also, wave parameter variations were less important in radial and tangential directions. In addition, phase velocity and acoustic radiation – which significantly varied – were the best parameters for quality assessment of poplar wood compared with group velocity and attenuation coefficients. Since samples near the bark were acoustically better than counterparts near the pith, they could be used in products requiring more strength, like lumber. Finally, acoustic radiation and phase velocity were correlated more strongly with density than group velocity and attenuation.  相似文献   
7.
Soil salinity presents a serious threat to crop production. The relatively poor tolerance to this stress agent exhibited by conventional crops incentivizes the search for alternative producers of food and forage in salinity-affected environments. Halophytes belonging to the genus Salicornia L. have been suggested as being able to provide both forage and edible seed oil. Here, a set of 14 Salicornia europaea L. accessions was investigated for their ability to produce seed oil and forage in response to a range of salt concentrations (100, 300 and 600 mM NaCl) in the water used for irrigation. Seed of the accessions was collected from diverse sites close to saline rivers and the sea in Iran. Salinity was shown to have a major effect on biomass yield, and on seed oil yield and composition. The ratio of unsaturated to saturated fatty acids in the seed oil was remarkably high. Forage yield was highest when irrigated with 300 mM NaCl for most of the accessions, while a level of 600 mM NaCl suited the production of seed oil.  相似文献   
8.
The present study was conducted on a group of Iranian mothers with icteric newborn in order to identify any wrong knowledge and improper practices related to the neonatal jaundice. Such an estimate of knowledge and practices of mothers may be required for implementing the educational programs on which the preventive measures of kernicterus are principally thought to be depended. Between June 2004 and February 2007, 1666 mothers with icteric newborn hospitalized at a single center were enrolled. A questionnaire was used to assess the participants' knowledge and practice of neonatal jaundice. A knowledge score was calculated based on the responses. The mean knowledge score was 3.38 +/- 1.23 (out of 6). About 77% of the mothers had moderate-to-high level of knowledge of neonatal jaundice. Approximately one-third of the mothers consulted a physician within 24 h of appearance of jaundice and 13.8% declared that they waited and managed their children with traditional remedies until they sought medical advices. Furthermore, 32.2% of the mothers discontinued feeding their icteric offspring with colored foods and colostrums. Hence, 42.8% of the mothers acted weakly with regard to their icteric offspring. The health care workers were the participants' major source of information about neonatal jaundice. The present study determined a fairly adequate knowledge of Iranian mothers about the neonatal jaundice with incomparable level of related practices. The findings of this study should be considered seriously by the local health centers and the medical professionals to provide consistent information about jaundice and its causes for the parents.  相似文献   
9.
Aquaculture International - This study was performed to investigate the effects of dietary acetic acid, probiotic protexin, and their combination on growth performance, intestinal microbiota,...  相似文献   
10.
Artificial keratoprostheses are indispensable for visual rehabilitation in patients with end-stage corneal blindness. This study aimed to assess the biocompatibility of polyethylene terephthalate nanofibrous mats and its potential as a novel synthetic keratoprosthesis skirt material for corneal tissue engineering. Nanofibrous mats were prepared by an electrospinning method and were first treated with the CO2 plasma to yield carboxylic groups on the surface; finally, the modified PET mat was cross linked with collagen using water-soluble carbodiimide as a coupling agent. The samples were evaluated by ATR-FTIR, scanning electron microscope (SEM), contact angle, and cell culture. The cross-linking of collagen on PET surface was confirmed by ATR-FTIR spectroscopy and SEM images The 79° difference was obtained in the contact angle analysis, obtained for the collagen-cross-linked nanofibrous mat than the non-modified nanofibrous mat. Cellular investigation showed limbal epithelial progenitor cells (LEPCs) has been better adhesion, cell growth, and proliferation of collagen-crosslinked nanofibrous samples than other samples. The bioavailability of PET fibers with covalently attached collagen was found to be identical to that of PET fibers with covalent attachment is a suitable method for enhancing the biocompatibility of scaffolds special as a good skirt in keratoprosthesis designs.  相似文献   
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