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71.
Few studies have focused on Rift Valley fever virus (RVFV) transmission in less arid, transitional landscapes surrounding known high-risk regions. The objective of this study was to identify evidence of RVFV exposure in Bodhei Village in a forested area at the edge of the RVFV-epidemic Garissa region. In a household cluster-based survey conducted between epidemics in early 2006, 211 participants were enrolled. Overall seroprevalence for anti-RVFV was high (18%) and comparable with rates in the more arid, dense brush regions farther north. Seroprevalence of adults was 28%, whereas that of children was significantly lower (3%; P < 0.001); the youngest positive child was age 3 years. Males were more likely to be seropositive than females (25% versus 11%; P < 0.01), and animal husbandry activities (birthing, sheltering, and butchering) were strongly associated with seropositivity. The results confirm that significant RVFV transmission occurs outside of recognized high-risk areas and independent of known epidemic periods.  相似文献   
72.
Foot‐and‐mouth disease (FMD) vaccines are routinely used as effective control tools in large regions worldwide and to limit outbreaks during epidemics. Vaccine‐induced protection in cattle has been largely correlated with the FMD virus (FMDV)‐specific antibodies. Genetic control of cattle immune adaptive responses has been demonstrated only for peptide antigens derived from FMDV structural proteins. Here, we quantify the heterogeneity in the antibody response of cattle primo‐vaccinated against FMD and study its association with the genetic background in Holstein and Jersey sires. A total of 377 FMDV‐seronegative calves (122 and 255 calves from 16 and 15 Holstein and Jersey sires, respectively) were included in the study. Samples were taken the day prior to primo‐vaccination and 45 days post‐vaccination (dpv). Animals received commercial tetravalent FMD single emulsion oil vaccines formulated with inactivated FMDV. Total FMDV‐specific antibody responses were studied against three viral strains included in the vaccine, and antibody titres were determined by liquid‐phase blocking ELISA. Three linear hierarchical mixed regression models, one for each strain, were formulated to assess the heterogeneity in the immune responses to vaccination. The dependent variables were the antibody titres induced against each FMDV strain at 45 dpv, whereas sire's ‘breed’ was included as a fixed effect, ‘sire’ was included as a random effect, and ‘farm’ was considered as a hierarchical factor to account for lack of independence of within herd measurements. A significant association was found between anti‐FMDV antibody responses and sire's breed, with lower immune responses found in the Jersey sires’ offspring compared with those from Holstein sires. No significant intrabreed variation was detected. In addition, farm management practices were similar in this study, and results of the serological assays were shown to be repeatable. It therefore seems plausible that differences in the immune response may be expected in the event of a mass vaccination campaigns.  相似文献   
73.
Summary 1. In 168 necropsies performed during a period of less than 3 years, 6 cases of primary carcinoma of the liver were found, an incidence of 3.57%. Another case was proved by needle biopsy, but autopsy was not obtained. Six of the 7 carcinomas were diagnosed during the life of the patients concerned.2. Clinical diagnosis was established upon a history of progressive and rapid general deterioration of health, with anorexia and marked emaciation accompanied by painful nodular hepatomegaly and fever, and later by moderate jaundice and serosanguineous ascitic effusion.3. The disproportion between the slightly elevated values of serum bilirubin and the high alkaline phosphatase activity, together with an increase of the transaminase levels, were the most important laboratory data, allowing the diagnosis of expanding space-occupying lesion (though not specifying its precise nature).The practical application of these criteria to diagnosis may be rewarded with an increase in in-vivo diagnosis of neoplasms of the liver.Pathologic examinations were carried out at the Instituto de Anatomia Patológica.  相似文献   
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Parasites are natural regulators of their host populations. Despite this, little is known about variations in parasite composition (spatially or temporally) in environments subjected to water-related periodic stress such as the arid and semiarid regions. The objective of this study was to evaluate the spatial-temporal variation in endoparasite species’ abundance and richness in populations of Neotropical Cnemidophorus ocellifer, Tropidurus hispidus, and Tropidurus semitaeniatus lizards in the semiarid northeast of Brazil. The location influenced the abundance of parasites in all analyzed lizard species, while season (dry and rainy) only influenced the total abundance for T. hispidus. In all seasons, males significantly showed more endoparasites than females in all lizard species, although for T. hispidus, this difference was only found in the dry season. Seasonal variations affect the abundance patterns of parasites. Likely, variables include environmental variations such as humidity and temperature, which influence the development of endoparasite eggs when outside of the host. Further, the activity of the intermediate hosts and the parasites of heteroxenous life cycles could be affected by an environmental condition. The variation in the abundance of parasites between the sampling areas could be a reflection of variations in climate and physiochemical conditions. Also, it could be due to differences in the quality of the environment in which each host population lives.  相似文献   
77.
The study objectives were to characterize the morphology of the parasitic forms and describe the prevalence and intensity of Haemogregarina spp. in a population of the turtle Podocnemis unifilis as well as to examine the relationships between parasitism and turtle variables such as gender, size, and weight. Samples were taken in the Tapajós and Jamanxim rivers, Itaituba, Pará state, Brazil. Blood was collected from the tail vein of 72 P. unifilis specimens, including 35 males, 36 females, and one unsexed juvenile. The prevalence of Haemogregarina spp. was 98 % (n?=?71). The mean parasite intensity of Haemogregarina spp. was 118 (1–582) parasites/2000 blood cells (6 %). There was no significant difference in the mean parasite intensity between male (137.68?±?121.8, n?=?35) and female turtles (101.42?±?123.59, n?=?35). There was no relationship between parasite intensity and carapace length. Although the relationship between parasite intensity and host body weight was significant, the relationship was weak. This is the first study on Haemogregarina parasitism with a relatively high number of turtles in Brazil.  相似文献   
78.
7‐keto‐DHEA (3β‐hydroxy‐androst‐5‐ene‐7,17‐dione) is included in section S1 of the World Antidoping Agency (WADA) List of Prohibited Substances. The detection of its misuse in sports needs special attention, since it is naturally present in urine samples. The main goal of this study is to investigate the in vivo metabolism of 7‐keto‐DHEA after a single administration to healthy volunteers and to better describe the relationship between arimistane (androst‐5‐ene‐7,17‐dione) and 7‐keto‐DHEA after the application of the common routine procedures to detect anabolic steroids in WADA accredited antidoping laboratories. Free, glucuro‐, and sulpho‐conjugated steroids extracted from urine samples obtained before and after the administration of 7‐keto‐DHEA were analyzed by different gas chromatographic (GC)–mass spectrometric (MS) techniques. Gas chromatography coupled to tandem MS to study the effect on the endogenous steroid profile, coupled to isotope ratio mass spectrometry (IRMS) to investigate the potential formation of androgens derived from DHEA and coupled to high resolution accurate mass spectrometry (HRMS) to investigate new diagnostic metabolites. The analysis by IRMS confirmed that there is no formation of DHEA from 7‐keto‐DHEA. Ten proposed metabolites, not previously reported, were described. These include reduced and hydroxylated structures that are not considered part of the steroid profile in antidoping analyses. They showed considerable responses in all fractions analyzed. Some deoxidation reactions (including arimistane formation) were found and most probably can be linked to the sample preparation or instrumental analysis. This is important when interpreting the results after the application of procedures to detect steroids in urine currently used in antidoping laboratories. 7‐keto‐DHEA metabolism in humans for antidoping purposes was studied and unexpected results were found. This could lead to a misinterpretation of the data, depending on the procedure applied and the analytical instrumentation used.  相似文献   
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Objectives:To characterize upper airway volume and morphology in patients with different skeletal patterns of Class II malocclusion compared to Class I.Materials and Methods:A total of 197 individuals who had cone-beam computed tomography were allocated into groups according to ANB, SNA, and SNB angles (Class I, Class II maxillary protrusion, Class II mandibular retrusion), each subdivided into hypodivergent, normal, and hyperdivergent. Nasopharynx (NP), oropharynx (OP), and hypopharynx (HP) were assessed with three-dimensional image reconstruction software.Results:Intergroup comparison did not detect significant differences in volume and morphology of NP, OP, and HP. The males displayed larger OP and HP volume than the females. Positive correlations between age and NP, OP, HP volume and between craniocervical angle and OP and HP volume were observed. Linear regression analysis detected a tendency for OP and HP volume to increase as maxillary and mandibular length increased.Conclusions:Upper airway volume and morphology were similar in different skeletal patterns of Class II malocclusion. Actual upper and lower jaw lengths were more closely related to upper airway volume and morphology than the angles that reflected their position relative to the cranial base.  相似文献   
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