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61.
Background:Inflammatory bone resorption in periodontitis can lead to tooth loss. Systemic administration of bisphosphonates such as risedronate for preventing bone resorption can cause adverse effects. ALG and PLGA microparticles have been studied as drug delivery systems for sustained release of drugs. Therefore, the release pattern of risedronate from PLGA microparticles embedded with ALG was studied as a drug delivery system for sustained release of the drug, which can be used in local administrations. Methods:Risedronate-containing PLGA microparticles were fabricated using double emulsion solvent evaporation technique. Ionic cross-linking method was used to fabricate risedronate-loaded ALG. Risedronate-containing PLGA microparticles were then coated with ALG. The calibration curve of risedronate was traced to measure EE and study the release pattern. SEM imaging was carried out, and cell toxicity was examined using MTT assay. Statistical analysis of data was carried out using SPSS ver. 20 software, via one-way ANOVA and Tukey’s tests. Results:SEM imaging showed open porosities on ALGs. The mean EE of PLGA microparticles for risedronate was 57.14 ± 3.70%. Risedronate released completely after 72 h from ALG, and the cumulative release was significantly higher (p = 0.000) compared to PLGA microspheres coated with ALG, which demonstrated sustained released of risedronate until day 28. Risedronate-loaded ALG showed a significant decrease in gingival fibroblasts cell viability (p < 0.05). Conclusion: Alginate-coated PLGA microspheres could release risedronate in a sustained and controlled way and also did not show cell toxicity. Therefore, they seem to be an appropriate system for risedronate delivery in local applications. Key Words: Alginates, Hydrogels, Polylactic acid-polyglycolic acid copolymer, Risedronic acid  相似文献   
62.
Growth performance, carcass quality, survival and haematological responses were determined when Huso huso juvenile (41.7±1.8 g) fed diets containing Ergosan (an algal product) at 0, 2.0, 4.0 and 6.0 g kg−1 for 60 days. Each diet was fed to triplicate groups of fish at 10-day intervals (1–10, 20–30 and 40–50 with non-supplemented diets and 10–20, 30–40 and 50–60 with supplemented diets). Results showed that fish fed diets containing Ergosan had significantly higher growth than the control group ( P <0.05). Survival was not different among all dietary treatments ( P >0.05). Food conversion ratio in the fish fed a diet containing 4.0 and 6.0 g kg−1 Ergosan was significantly better than the other treatments ( P <0.05), whereas protein efficiency ratio was not different between experimental diets. Lymphocyte count in the fish fed diets containing Ergosan was higher than the other treatments. Haematocrit, haemoglobin (Hb) concentration, number of erythrocytes, total leucocytes, monocyte, eosinophil, myelocyte, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration were not different between treatments. Neutrophil count in the control group was higher than the fish fed supplemented diets. Furthermore, whole body lipid, moisture and fibre were not different among dietary treatments ( P >0.05) but body protein in the fish fed a diet containing Ergosan at the level of 2.0 and 4.0 g kg−1 was higher than the other treatments. Whole body ash content was higher in the control group. It was concluded that dietary administration of Ergosan can influence some growth and haematological parameters in great sturgeon, H. huso juveniles.  相似文献   
63.
Land evaluation is the process of land performance predictions over time based on land uses and soil features. Traditional methods in determining soil features are proved to be time-consuming and costly. Therefore, in order to overcome these limitations, a simpler automated method using the image segmentation was developed in this study. The method was designed by integrating dynamic region merging and genetic algorithm. An area index was calculated for each soil profile using the automated method. It was used to present the amount of soil coarse particles and thereupon to determine the rating value of text-structure. Using the method, the mean intersection over union of above 0.7 was obtained for detecting the coarse particles which confirms its suitability. Data analysis showed that (a) compared to the Storie-land index (R2 = 0.71), the Square root-land index was more correlated to the harvest index (R2 = 0.73), and (b) comparing to manual methods, not only the automated text-structure had a higher correlation with the harvest index (R2 = 0.64) but also it decreased the determination time (>3.75 times). Furthermore, among the models developed by response surface methodology for estimation of soil features, the developed model for estimation of soil lime showed the highest accuracy (R2 = 0.89). In conclusion, since the developed method is more accurate, more economic and faster than the usual manual methods, it can be widely used in land suitability evaluation.  相似文献   
64.
The aims of this study are to determine the geographical and ecological distribution of nine Aegilops species in Republic of Armenia and to make an assessment of their IUCN Red List status, using the IUCN Red list categories and criteria, in order to develop an in situ conservation strategy for wild relatives of wheat in Armenia. Ecogeographic surveys of nine Aegilops species were undertaken over 2 years in Armenia. They included a herbarium survey followed by extensive ground-truthing field surveys where targeted Aegilops species occur. The study showed that of the nine Aegilops species studied, four are threatened and of these, Ae. mutica and Ae. crassa are critically endangered. The latter species may even be extinct in Armenia. Ae. neglecta and A. biuncialis are endangered. Additional studies are required to assess the threat status of Ae. umbellulata. Ae. columnaris was assessed as near threatened, while the remaining species (Ae. triuncialis, Ae. cylindrica and Ae. tauschii) are of least concern. There has been a dramatic decline in the genetic resources of Aegilops species during recent years in Armenia as a result of adverse human impacts such as expansion of agriculture, urbanization and uncontrolled grazing. Several species, especially Ae. mutica and Ae. crassa, should be prioritized in conservation activities in Armenia. Efforts should be made to conserve genetic diversity of crop wild relative species both in situ and ex situ, bearing in mind that their germplasm carries potentially valuable information (traits) that can improve adaptability and productivity of cultivated wheat varieties.  相似文献   
65.
66.
The primary objective of this study was to determine the diversity and intensity of ticks found on camels (Camelus dromedarius) and their seasonal population dynamics in Kerman, southeast of Iran. For this purpose, a total of 426 tick specimens were collected from 217 infested camels in southeast of Iran during activating seasons of ticks (April 2009 to March 2010). The species collected from camel were Hyalomma dromedarii (84.7%), Hyalomma marginatum (8.7%), Hyalomma anatolicum excavatum (5.4%), and Hyalomma anatolicum anatolicum (1.2%). The highest seasonal activities occurred in summer. The ratio of male ticks was more than female ticks. H. dromedarii was the predominant tick species and accounted for 84.7% of the ticks.  相似文献   
67.
Five species of nematodes and cestodes were collected from alimentary canals of pigeons: the nematodes were two species: Ascaridia colombae (16.66%) and Hadjelia truncata (1.96%), while the cestodes were Cotugnia digonopora (13.79%), Raillietina magninumida (18.62%) and Raillietina achinobothridia (32.35%); fecal examination revealed: Eimeria spp. (40.19%) and Cryptosporidium oocysts (2.94%); and blood smears showed: Haemoproteus cloumbae (47/05%); in mouth, throat and larynx: Trichomonans gallinae (57.84%); four species of ectoparasites were collected from feathers and subcutaneous nodules as follows: feathers: Pseudolynchia canariensis (63.72%), Columbicola columbae (79.41%), Menopen gallinea (44.11%); subcutaneous nodules: Laminosioptes cysticola (1.96%). From the parasitic fauna identified in this study, it is imperative to institute an integrated parasitic control through constant changing of litter, regular use of antihelminthics, anticoccidials and dusting of birds with pesticides.  相似文献   
68.
Abstract

A two-year field experiment was conducted to investigate the impact of short crop rotation and organic amendments on rapeseed yield under weed competition conditions. The primary experimental plots consisted of either triticale or pea as a prior crop, consisting of four subplots with either 25 tons of composted cattle manure (CCM), 150?kg urea N ha?1 (N), 25 tons composted cattle manure + 75?kg urea N ha?1 (CCM?+?N), or no urea N or manure added as the control (C0). Rapeseed seed yield was not significantly affected by previous crops, except for rapeseed grown after pea which had slightly higher seed yield (2058?kg ha?1) than those grown after triticale (1942?kg ha?1). Plants that received CCM?+?N produced the highest amount of seed yield (2447?kg ha?1), but were not significantly different from plants that received just urea N (2218?kg ha?1). Weeds gained more biomass when the previous crop was pea compared to those whose previous crop was triticale. Weeds in plots that received CCM?+?N produced the greatest biomass, followed by N, and CCM plots, respectively.  相似文献   
69.
This research was carried out in order to detect the prevalence of nymphal stages of Linguatula serrata in mediastinal and mesenteric lymph nodes of sheep slaughtered in Kerman slaughterhouse, southeast of Iran. For this purpose, mesenteric and mediastinal lymph nodes of 806 sheep of different sex and age were examined. One hundred and thirty out of 806 (16.1%) of the sheep were found positive for L. serrata infection. The infection rate increased with age (P < 0.001). Prevalence of L. serrata nymphs in males and females and different seasons was not significantly different (P > 0.05). Considering the results, it could be concluded that the prevalence of L. serrata in sheep of Kerman is high and plays an important role in epidemiology of linguatulosis. The zoonotic potential of this parasite to human health is discussed.  相似文献   
70.
Drought is an important limiting factor which can cause major loss in barley productivity. A field experiment was conducted to investigate the effects of irrigation regimes on assimilate remobilization and photosynthetic characteristics of five barley cultivars in 2012 and 2013. There were four levels of irrigation including well-watered [soil moisture content in root depth kept at 100% field capacity (FC)], mild drought (75% FC), severe drought (50% FC), and very severe drought (25% FC). Results showed that Karoon and Valfajr cultivars had the maximum net photosynthetic rate (Pn) ranged from 16.3 to 19.3 µmol CO2 m?2 s?1 under very severe drought. Stomatal conductance (gs) was affected by drought so that Karoon and Valfajr had the lowest gs under severe and very severe drought. By improving the drought, remobilization efficiency in Karoon and Valfajr increased from 18.3% in well-watered to 54.1% under severe drought. In both years under severe and very severe drought, maximum 1000-grain weight and grain yield was obtained in Valfajr and Karoon. Overall, in arid areas, applying suitable irrigation regimes such as mild or severe drought can control soil drying, so that suitable cultivars such as Karoon and Valfajr can rehydrate overnight, and yield might not be inhibited severely.  相似文献   
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