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101.
Fabrication of Ceftazidime (CTZ) loaded silk fibroin/gelatin (SF/GT) nanofibers (NFs) without the loss of structure and bioactivity of CTZ was demonstrated by electrospinning method. The structure, morphology and mechanical properties of the electrospun SF/GT nanofibrous mats were characterized using FT-IR, SEM and DSC. The drug release profile of different electrospun fibers was analyzed using spectrophotometric method, and also diffusion method was applied to assess the antibacterial effect of NFs. Cell viability was evaluated by MTT assay. The results show that the average diameter of drug loaded NFs at the optimum polymer to drug feeding ratio (10:1) was 276.55±35.8 nm, while increasing the feeding ratio to 1:1 increases the average diameter to 825.02±70.3 nm. FT-IR of drug loaded NFs was revealed that CTZ was successfully encapsulated into NFs while viability study approved cytocompatibility of SF/GT NFs. CTZ was released from NFs during 6 h, and formation of inhibition zone in diffusion test demonstrated the antibacterial effect of drug loaded NFs. Altogether, the CTZ loaded SF/GT NFs can improve the drug effectiveness particularly in the prevention of post-surgical adhesions and infections for wound dressing.  相似文献   
102.
The polyphagous obligate parasites Meloidogyne spp. devastate a wide range of crop plants including bananas and plantains. Their infestations impact agriculture worldwide. Therefore, an effective combating regime against this nematode species and an in-depth understanding of plant-nematode interaction are essential. Early detection of infection by visual inspection is not possible. This hampers early control strategy efforts and makes in-depth research of the early infection and plant defence unfeasible. A simple and robust in planta PCR-based nematode detection method is described here as the first crucial step. This PCR-based detection assay exploits the existence of the Internal Transcribed Spacer 1 (ITS 1) region of the ribosomal DNA (rDNA) gene family in the nematodes for early detection of nematode penetration into the roots. The results demonstrate that this detection assay is suitable to serve as a molecular screening tool for plant root diagnostic purposes.  相似文献   
103.
This research was aimed to investigate the prevalence and clinical impact of occult HBV infection in thalassemic patients with chronic HCV infection. In this cross-sectional study we have totally examined 60 patients suffering HBV and HCV infections by PCR and RT-PCR methods, respectively, in Kerman province of Iran. ELISA technique (RADIM, Italy) was used to detect anti-HBc, anti-HBs and HBsAg. The serum level of liver enzymes (SGOT, SGPT, DB, TB and ALK) were analyzed in the HCV infected patients (MAN, IRAN). Statistical analyses performed using t-test and Chi-square. We found that 27 cases (out of 60) were infected by HCV but HBV-DNA was not seen in HCV infected patients. Present findings also showed that none of samples were HBsAg positive but 9 (33%) (out of 27) HCV-RNA positive patients were anti-HBc positive and 11 (40.7%) were positive for anti-HBs. We found that SGOT, SGPT, DB, TB and ALK are above normal in 27 (100%), 19(70.3%), 12(44.5%), 15 (55.5%) and 15 (55.5%) RNA-HCV positive patients, respectively. The prevalence of hepatitis C infection is very high in thalassemic patients and based on other studies our results showed that the prevalence of HCV infection in Kerman is more than other provinces of Iran. In contrast with other studies HBV-DNA in these patients could not be detected, hence, it seems that occult HBV infection isn't frequent in Iranian thalassemic patients who suffering from chronic HCV infection.  相似文献   
104.
Almost all environmental management comes at an economic cost that may not be borne equitably by all stakeholders. Here, we investigate how heterogeneity in catch and profits among fishers influences the trade‐off among the triple‐bottom‐line objectives of recovering a fish population, maximizing its economic value and distributing restrictions equitably across fishers. As a case‐study, we examine management reform of an ecologically and economically important coral reef fishery operating within the Great Barrier Reef Marine Park. Using a simulation model, we find that total profitability of the fishing industry is 40% lower if recovery plans are equitable when compared to the most economically efficient plan. However, efficient recovery plans were typically highly inequitable because they required some fishers to cease fishing. Equity was defined according to different norms, and the efficiency loss was greatest when catch losses were shared equally across fishers rather than in proportion to their historical catch. We then varied key social, economic and biological parameters to identify cases when equity and efficient recovery would trade‐off most strongly. Recovery plans could be both efficient and equitable when heterogeneity in fisher's catches and individual catch efficiencies was lower. If fishers were homogenous then equitable plans could have maximal economic efficiency. These results emphasize the importance of considering heterogeneity in individual fishers when designing recovery plans. Recovery plans that are inequitable may often fail to gain stakeholder support, so in fisheries with high heterogeneity we should temper our expectations for marked increases in profits.  相似文献   
105.
Grain yield and protein content are traits of major importance in wheat breeding, but their combination is challenging due to a tight negative correlation. Protein yield and grain protein deviation have been proposed as selection criteria to simultaneously improve both traits. Sedimentation volume is an indicator of protein quality, which plays an important role for bread‐making quality in wheat. All these traits have been investigated in our study with 135 parental inbred lines, their 1,604 hybrids and 10 commercial check varieties evaluated at five environments. The focus of our study was to investigate the usefulness of the grain protein deviation and to define a bivariate model for calculating the grain protein deviation. Further, we compared line and hybrid wheat for grain yield and quality‐related parameters such as protein content and sedimentation volume. The grain protein deviation determined with a bivariate model delivered robust estimates of variance components and enabled a balanced selection of genotypes with improved protein content and grain yield across different quality classes. Although heterosis for protein content and sedimentation volume was negative, hybrids had a higher grain protein deviation as well as higher grain yield at a given sedimentation volume or a given protein content than line varieties.  相似文献   
106.
Seedlings of sugar beet (Beta vulgaris) were grown in nutrient solutions containing a range of Cu and Zn concentrations. Based on measurements of shoot and root length and dry weight, copper was found to be already toxic at 10 μM, while Zn became toxic at 100 μM. At Cu and Zn levels found to induce a similar level of growth inhibiton, the influence of increasing the supply of K, Ca and Mg was investigated. Increasing the concentration of both Ca and Mg in the nutrient solution attenuated the degree of inhibition of root growth by Zn, but not Cu. Potassium did not affect the toxicity of either Cu or Zn. An increase in Ca decreased the level of both Cu and Zn in roots. Magnesium ameliorated the toxicity effects of Zn without effecting the Zn concentration in the roots. Treatment with Zn significantly decreased the concentration of Mg in the roots. An increased supply of Mg lowered the percentage decrease in root Mg concentration due to Zn toxicity. The maintenance of an adequate Mg level in the roots may be critical to prevent Zn induced inhibition of root growth.  相似文献   
107.
The present work aimed to describe the normal computed tomography (CT) and cross‐sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross‐sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep.  相似文献   
108.
1. White Leghorn cockerels were exercised continuously for 45 minutes on a treadmill at work loads equivalent to 2.1 and 2.7 times pre‐exercise metabolic rates, the latter being close to the performance limits of the experimental birds.

2. Relative blood flow to the abdominal viscera and selected leg muscles was estimated using 113Sn‐, 153Gd‐ and 46Sc‐labelled microspheres, injected into the root of the aorta.

3. There was no significant shift of blood flow away from the viscera towards the leg muscles at either work load. However, relative colonic and duodenal blood flow fell significantly at both work loads and relative pancreatic blood flow doubled at the higher work load.

4. It is concluded that, as previously reported in female domestic fowl performing physical exercise close to their performance limits, male fowl are largely refractory to shifts in blood flow away from the viscera to the working muscles. Nevertheless, there is evidence of blood flow shifts between visceral organs, probably related to the intermediary metabolism of fuel substrates.  相似文献   

109.
The effects of feeding Artemia nauplii enriched with or without poly‐β‐hydroxybutyrate (PHB) and/or highly unsaturated fatty acids (HUFA) on Siberian sturgeon (Acipenser baerii) larvae were investigated. Feeding larvae with PHB‐enriched nauplii (PHB, PHB + HUFA) decreased the growth performance of the larvae. PHB affected the body composition by increasing the lipid content of the whole body and decreasing total saturated, monoenoic, n3, n6 and decosahexanoeic acid (DHA) in the larvae, indicating that the PHB addition affected lipid metabolism. A high activity of pepsin was observed in the digestive extracts of PHB treatments (PHB, PHB + HUFA), while PHB suppressed amylase activity in the intestine of the larvae. Based on molecular analysis, PHB changed the microbial community in the distal intestine of the larvae. The highest counts of goblet cells were observed in the HUFA‐containing treatments (HUFA, PHB + HUFA), indicating that HUFA addition may improve the mucosal barrier defence system. The overall quality of the larvae was evaluated by exposing them to different salinities and ammonia stress levels. PHB decreased survival rates in these challenges. Our results show that optimal PHB doses for bio‐encapsulation into Artemia remain to be determined for further application at the earliest larval stages of sturgeon.  相似文献   
110.
4‐Nonylphenol (NP) is an emerging concern contaminant which is widely spread in the aquatic ecosystem. Nigella sativa seed (NSS) has multifaceted therapeutic values. This study aimed to give insight into the potential protective effect of NSS on NP‐induced haematotoxicity in Clarias gariepinus through evaluation of haematological parameters, oxidant/antioxidant balance of blood lysate and histopathological investigation of blood smear. One hundred and fifty fish were divided into five groups (30/group). First group served as control which did not received NP exposure and fed basal diet without NSS supplementation. The other four groups were exposed to NP at a dose of 0.1 mg L?1 and fed diets supplemented with NSS at levels of 0, 10, 25 and 50 g/kg diet, respectively. Macrocytic hypochromic anaemia, thrombocytopenia, leucopenia, neutrophilia, lymphopenia, monocytosis and eosinophilia were observed following NP exposure together with increase in morphological erythrocyte alterations and micronuclei formation. Elevation in total peroxide and malondialdehyde and depletion in total antioxidant capacity of blood lysate were reported. We concluded that supplementation of NSS markedly ameliorated the previously listed manifestations, and the most effective doses were 25 and 50 g/kg feed.  相似文献   
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