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41.
The fall armyworm Spodoptera frugiperda is a polyphagous pest that causes important damage in different regions of America and mainly affects corn crops in both tropical and subtropical areas. Currently, control relies on both transgenic plants and/or chemical pesticides. In this work we describe the preparation of an indexed combinatorial library of amides and its toxic effect by contact against S. frugiperda . (E)-1-(1-Piperidinyl)-3-[4-(trifluoromethoxy)phenyl]-2-propen-1-one was the most active compound with an LD(50) = 0.793 μg mg(-1) of larva. This amide was also evaluated by ingestion and at the lowest concentration (1 mg kg(-1)) achieved 83.3% mortality.  相似文献   
42.

Successful preventive and control measures of zoonotic diseases require updated epidemiological data. Sylvatic rabies is endemic in Oman since 1990. Studying of the prevalence of animal rabies in Oman (2017–2019) was the goal of the current study besides the clinical–histopathological investigations of rabies in different animal species. A total of 117 whole brains of different animal species from different regions of Oman were examined by fluorescent antibody test (FAT) and histopathology for rabies during 2017–2019. Sixty-four samples (54.7%) were positive for rabies by FAT. The most affected species were goat (53.1%) followed by camel (18.8%), which pose a great risk to farmers and veterinarians. Positive fox cases were (10.9%). Most confirmed cases of animal rabies were submitted from Northern regions of Oman. Rabies was reported recently in Al Wusta among wild ruminants, Central Oman. The seasonal cycle of animal rabies in Oman was year-round with the peak from December to April. The clinical signs and neuropathological findings were nearly similar in different animal species. Histopathology-positive cases had Negri bodies in pyramidal and purkinje neurons, non-suppurative encephalitis features, and neuronal degeneration and necrosis. The sensitivity and specificity of histopathological diagnosis of rabies in different animals were 76.47% and 100.00%, respectively. Finally, sylvatic rabies remains a major challenge to the public and animal health in Oman. Although of the value of histopathological diagnosis of rabies if no other technique is available, other complementary tests must be employed to confirm negative results.

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43.
In this paper, we report on morphological diversity, ecology and flowering phenological records of an endangered and an endemic species of Morocco Pyrus mamorensis Trab. For this study, a survey was undertaken in North-Western Morocco (Mamora forest and Zaër region) whereby 67 accessions of P. mamorensis were sampled. A set of 33 genotypes of Pyrus spp. from the international collection INRA-Angers (France) of the genus Pyrus were also analyzed. The variability of the total of 100 accessions was assessed by twenty-six characters including fourteen qualitative and twelve quantitative traits. The results demonstrated high levels of morphological variation in the sampled accessions of P. mamorensis and established the relationships among the local germplasm using the UPGMA cluster analysis and the factorial discriminant analysis. Furthermore, we were able to distinguish three types of flowering in the Mamora forest: early, intermediate and late flowering type. Otherwise, the UPGMA classification comparing local accessions of P. mamorensis to the international collection led to the formation of four major groups showing the closest correspondence to their geographical origins: (1) The North African species represented by P. mamorensis, (2) The East Asian pea species, (3) The West Asian species and (4) The European species. These findings suggest the importance of implementing a conservation strategy preserving the genetic resources of wild pear in North-Western Morocco.  相似文献   
44.
Background: The seladin-1 (selective Alzheimer disease indicator-1), also known as DHCR24, is a gene found to be down-regulated in brain region affected by Alzheimer disease (AD). Whereas, hair follicle stem cells (HFSC), which are affected in with neurogenic potential, it might to hypothesize that this multipotent cell compartment is the predominant source of seladin-1. Our aim was to evaluate seladin-1 gene expression in hair follicle stem cells. Methods: In this study, bulge area of male Wistar rat HFSC were cultured and then characterized with Seladin-1 immunocytochemistry and flow cytometry on days 8 to 14. Next, 9-11-day cells were evaluated for seladin-1 gene expression by real-time PCR. Results: Our results indicated that expression of the seladin-1 gene (DHCR24) on days 9, 10, and 11 may contribute to the development of HFSC. However, the expression of this gene on day 11 was more than day 10 and on 10th day was more than day 9. Also, we assessed HFSC on day 14 and demonstrated these cells were positive for β-ш tubulin, and seladin-1 was not expressed in this day. Conclusion: HFSC express seladin-1 and this result demonstrates that these cells might be used to cell therapy for AD in future. Key Words: Seladin-1 (selective Alzheimer disease indicator-1), Alzheimer disease (AD), Hair follicle stem cells  相似文献   
45.
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   
46.
Preeclampsia is a disease regarding with altered vascular reactivity leading to hypertension of the mother and metabolic alterations in the fetus. This study aimed to assess nitric oxide and bleeding time following administration of magnesium sulfate to preeclamtic patients compared to normotensive pregnant women. A total of 112 subjects (56 preeclamtic patients and 56 normotensive pregnant controls) were enrolled in this case-control study. Cases and controls were matched for age, BMI, gestational age, parity and gravidity. Total concentration of nitrite and nitrate (NOx) was measured before and during magnesium sulfate (MgSO4) treatment using a modified Griess-based method. RESULTS: Systolic and diastolic blood pressures were significantly decreased during MgSO4 treatment in preeclamtic patients (p < 0.0001). NOx levels were significantly increased in preeclamtic women after MgSO4 administration (33.7 +/- 18.5 vs. 50.2 +/- 21.6, p < 0.0001) but it was not seen in normotensive parturients (52.4 +/- 28.9 vs. 57.3 +/- 21.7, p = 0.362). The bleeding time was scarcely increased following magnesium sulfate treatment in preeclamptic patients compared to normotensive pregnant women but it was not significant (p = 0.18). In addition, there was only a significantly reverse correlation between NOx levels and systolic or diastolic blood pressure in preeclamtic parturients after MgSO4 treatment (r = -0384; p = 0.003 and r = -0.29; p = 0.03, respectively). This study demonstrates that administrating MgSO4 to preeclamtic patients induced significant changes in NOx production which had a major role in modulating vasculature changes in preeclamsia.  相似文献   
47.
Journal of Crop Science and Biotechnology - The analysis of genetic diversity in medicinal plant species can greatly facilitate germplasm conservation and selection for use in breeding schemes. The...  相似文献   
48.
Genetic Resources and Crop Evolution - Hymenocrater comprises of 11 species throught the world. The genus is an Irano-Turanian elements, which has several usages in traditional medicine. Northeast...  相似文献   
49.
Background: Diabetes is a major public health problem. The development of new therapies that are able to improve glycemia management and even to cure diabetes is of great interest. In this study, protective effects of sodium tungstate against STZ-induced beta-cell damages were investigated. Methods: Sixty rats were divided into six groups: control, diabetic, sodium tungstate treated diabetic rats from one week before STZ injection (TDB), food-restricted diabetic (FRD), tungstate treated control, sodium tungstate treated diabetic rats from one week after STZ administration (TDA). We evaluated serum insulin, glucose and glucose tolerance; liver glycogen content, glucokinase (GK) activity; blood and pancreas antioxidant power, lipid peroxidation; and fuchsin-aldehyde histochemical staining of beta-cells. Results: Blood glucose levels of TDB group were lower than other diabetic groups (P<0.01). Blood insulin levels of all diabetic groups were lower than controls (P<0.01). Glucose intolerance improved in TDB animals. Blood and pancreas antioxidant power, liver glycogen contents and GK activities and granulated beta cells increased in TDB rats in comparison with other diabetic groups (P<0.01). Likewise, lipid peroxidation decreased significantly in TDB rats (P<0.01). Conclusions: Results suggested that sodium tungstate if administrated before STZ injection improves glycemic state by a direct effect on pancreatic beta-cells and preserves them by reducing the activity of these cells at the time of STZ injection, reducing STZ-induced oxidative stress, reducing insulin secretion, or all of the above mentioned.  相似文献   
50.
Behavioural thermoregulation enables ectotherms to access habitats providing conditions within their temperature optima, especially in periods of extreme thermal conditions, through adjustments to their behaviours that provide a “whole-body” response to temperature changes. Although freshwater fish have been detected as moving in response to temperature changes to access habitats that provide their thermal optima, there is a lack of integrative studies synthesising the extent to which this is driven by behaviour across different species and spatial scales. A quantitative global synthesis of behavioural thermoregulation in freshwater fish revealed that across 77 studies, behavioural thermoregulatory movements by fish were detected both vertically and horizontally, and from warm to cool waters and, occasionally, the converse. When fish moved from warm to cooler habitats, the extent of the temperature difference between these habitats decreased with increasing latitude, with juvenile and non-migratory fishes tolerating greater temperature differences than adult and anadromous individuals. With most studies focused on assessing movements of cold-water salmonids during summer periods, there remains an outstanding need for work on climatically vulnerable, non-salmonid fishes to understand how these innate thermoregulatory behaviours could facilitate population persistence in warming conditions.  相似文献   
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