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61.

Objective

The liver flukes, Fasciola spp. and Dicrocoelium dendriticum, infect ruminants and other mammalian extensively and cause major diseases of livestock that produce considerable economic losses.

Methods

A survey of 2391 sheep and goats slaughtered at an abattoir in Amol region, northern Iran was used to determine the prevalence of the liver flukes infection based on season, sex and specie of the animals.

Results

The results revealed that the prevalence rate of Fasciola spp. and Dicrocoelium dendriticum was 6.6% and 4.3% respectively. Dicrocoeliosis was more dominant in female animals (7.1%) whereas there was no sex-related difference in the prevalence of Fasciola spp. in male and female animals. Furthermore, Fasciolosis was significantly more prevalent than dicrocoeliosis in both sheep and goats. The Seasonal prevalence of Fasciola spp. was highest (P<0.005) during spring (8.3%) followed in order by autumn (8.1%), winter (5.9%) and summer (4.0%) but Dicrocoeliosis did not follow any seasonal pattern.

Conclusions

According to this study, it can be concluded that Amol is regarded as an endemic region for Fasciola spp and D. dandriticum infection. Moreover, Fasciola spp. is the most widespread liver fluke found in sheep and goats which is more dominant in sheep than goats.  相似文献   
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Dracunculiasis was rediscovered in Chad in 2010 after an apparent absence of 10 years. In April 2012 active village-based surveillance was initiated to determine where, when, and how transmission of the disease was occurring, and to implement interventions to interrupt it. The current epidemiologic pattern of the disease in Chad is unlike that seen previously in Chad or other endemic countries, i.e., no clustering of cases by village or association with a common water source, the average number of worms per person was small, and a large number of dogs were found to be infected. Molecular sequencing suggests these infections were all caused by Dracunculus medinensis. It appears that the infection in dogs is serving as the major driving force sustaining transmission in Chad, that an aberrant life cycle involving a paratenic host common to people and dogs is occurring, and that the cases in humans are sporadic and incidental.  相似文献   
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Fumonisin B1 is a common secondary metabolite produced by Fusarium moniliforme that occurs in corn and corn-based foods. This mycotoxin is toxic to many species of laboratory and domestic animals and is known to induce a variety of diseases such as hepatic cancer and renal and hepatic dysfunction. The structure of fumonisin B1 (FB1) resembles sphingolipids so it can inhibit synthesis of ceramide, an enzyme in the sphingolipid biosynthetic pathway. This inhibition leads to the disruption of sphingolipid metabolism and increased levels of sphinganine and sphingosine (sphingoid bases) in the serum of treated animals. It is believed that the toxicity effect of fumonisin B1 is the result of these sphingoid bases. In the present research, mice were treated with FB1 to determine its pathological effects on gastric gland and gastric mucosa in the treated mice. For this purpose, the mice were randomly assigned into two groups, namely, control (n?=?14) and treatment (n?=?15). The treatment group was fed with prepared food containing FB1 (150 mg/kg) for a period of 4 months. One day after the last treatment, all animals in both groups were euthanized and their stomach were sampled and prepared for microscopic analysis. Histopathological analysis revealed a significant decrease in parietal cell number and a significant increase in the number of inflammatory cells in gastric mucosa. Also, atrophy of gastric glands was observed. The study confirmed that FB1 poisoning can have toxicopathological effects such as gastric gland atrophy and gastritis on mice gastric tissue.  相似文献   
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Objective. To determine intrafamilial seropositivity of HBV and HCV and to compare them in families of infected persons with HBV and HCV in Hamadan clinic of hepatitis.Material and methods. In this analytic cross-sectional study, 651 family members of 200 HBV and HCV infection index cases were entered into the study and after signing an informed consent, they were referred to Blood Transfusion Center. With completion of laboratory tests, interviewers filled the questionnaires.Results. One hundred and eighteen (20.5%) and 107 (18.6%) family members were HBsAg and HBcAb positive respectively. 21 (3.6%) were isolated HBcAb positive. Only one person (1.3%) was HCVAb positive. The general rate of infection in family members of HBV infected people (atleast one case) (49.4%) was significantly higher than that of HCV infected people (3.3%), p < 0.001. Interspouses transmission was evaluated and prevalence of interspouses HBV and HCV infection were 32.3 and 8%, respectively.Conclusion. Intrafamilial and interspousal seropositivity of HBV is obviously more than those of HCV. More attention should be paid to screening and risk lowering activities particularly about HBV infected people and their families.  相似文献   
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Developments in the fields of lab-on-a-chip and microfluidic technology have benefited nanomaterial production processes due to fluid miniaturization. The ability to acquire, manage, create, and modify structures on a nanoscale is of great interest in scientific and technological fields. Recently, more attention has been paid to the production of core–shell nanomaterials because of their use in various fields, such as drug delivery. Heterostructured nanomaterials have more reliable performance than the individual core or shell materials. Nanoparticle synthesis is a complex process; therefore, various techniques exist for the production of different types of nanoparticles. Among these techniques, microfluidic methods are unique and reliable routes, which can be used to produce nanoparticles for drug delivery applications.

Developments in the fields of lab-on-a-chip and microfluidic technology have benefited nanomaterial production processes due to fluid miniaturization.  相似文献   
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