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1.
Bong Jin Kim Kyung Seob Song Hyun-Hee Kong Hee-Jae Cha Meesun Ock 《The Korean journal of parasitology》2014,52(1):85-87
We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections. 相似文献
2.
Mohamed M. Eid Samy I. El-Kowrany Ahmad A. Othman Dina I. El Gendy Eman M. Saied 《The Korean journal of parasitology》2015,53(1):51-58
Toxocariasis is a soil-transmitted helminthozoonosis due to infection of humans by larvae of Toxocara canis. The disease could produce cognitive and behavioral disturbances especially in children. Meanwhile, in our modern era, the incidence of immunosuppression has been progressively increasing due to increased incidence of malignancy as well as increased use of immunosuppressive agents. The present study aimed at comparing some of the pathological and immunological alterations in the brain of normal and immunosuppressed mice experimentally infected with T. canis. Therefore, 180 Swiss albino mice were divided into 4 groups including normal (control) group, immunocompetent T. canis-infected group, immunosuppressed group (control), and immunosuppressed infected group. Infected mice were subjected to larval counts in the brain, and the brains from all mice were assessed for histopathological changes, astrogliosis, and IL-5 mRNA expression levels in brain tissues. The results showed that under immunosuppression, there were significant increase in brain larval counts, significant enhancement of reactive gliosis, and significant reduction in IL-5 mRNA expression. All these changes were maximal in the chronic stage of infection. In conclusion, the immunopathological alterations in the brains of infected animals were progressive over time, and were exaggerated under the effect of immunosuppression as did the intensity of cerebral infection. 相似文献
3.
An advanced electro-active dry adhesive,which was composed of a mushroom-shaped fibrillar dry adhesive array actuated by an Ionic Polymer Metal Composite (IPMC) artificial muscle reinforced with nitrogen-doped carbon nanocages (NCNCs),was developed to imitate the actuation of a gecko's toe.The properties of the NCNC-reinforced Nafion membrane,the electromechanical properties of the NCNC-reinforced IPMC,and the related electro-active adhesion ability were investigated.The NCNCs were uniformly dispersed in the 0.1 wt% NCNC/Nafion membrane,and there was a seamless connection with no clear interface between the dry adhesive and the IPMC.Our 0.1 wt% NCNC/Nafion-IPMC actuator shows a displacement and force that are 1.6-2 times higher than those of the recast Nafion-IPMC.This is due to the increased water uptake (25.39%) and tensile strength (24.5 MPa) of the specific 3D hollow NCNC-reinforced Nafion membrane,as well as interactions between the NCNCs and the sulfonated groups of the Nafion.The NCNC/Nafion-IPMC was used to effectively actuate the mushroom-shaped dry adhesive.The normal adhesion forces were 7.85 mN,12.1 mN,and 51.7 mN at sinusoidal voltages of 1.5 V,2.5 V,and 3.5 V,respectively,at 0.1 Hz.Under the bionic leg trail,the normal and shear forces were approximately 713.5 mN (159 mN·cm-2) and 1256.6 mN (279 mN·cm-2),respectively,which satisfy the required adhesion.This new electro-active dry adhesive can be applied for active,distributed actuation and flexible grip in robots. 相似文献
4.
5.
Ana Rodríguez Takehiko Shimada Magdalena Cervera Ana Redondo Berta Alquézar María Jesús Rodrigo Lorenzo Zacarías Lluís Palou María M López Leandro Pe?a 《Plant signaling & behavior》2015,10(6)
Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores. 相似文献
6.
N. Billington † R. G. Danzmann P. D. N. Hebert R. D. Wards ‡ 《Journal of fish biology》1991,39(SA):251-258
Phylogenetic relationships among four Stizostedion species were examined using mitochondrial DNA (mtDNA) and allozyme analyses. Twenty-six allozyme loci were scored, and mtDNA variation was examined using 24 restriction endonucleases, yielding 48–57 restriction sites among the species. Genetic distance analyses show that the two North American species ( S. canadense and S. vitreum ) cluster in one group, while the two European species ( S. hciopercu and S. vogense ) form a second group. Nei's genetic distance between these two groups was 0.7 ± 0.2 for allozymes, while the corresponding mtDNA sequence divergence was 14.8 ± 2.0%, suggesting that these two groups diverged approximately 10 million years ago. Thus, these data are consistent with the hypothesis that Stizostedion colonized North America during the Pliocene. 相似文献
7.
Abstract: Age-related changes in the expression of Na,K-ATPase α1- and α3-isoform mRNAs were analyzed by in situ hybridization in the Fischer-344 rat hippocampus. Quantification of signal density with cRNA probes in rat hippocampus at 3 months of age showed (a) α1 content is 1.5 times higher in granule than in pyramidal cell layers, whereas α3 content shows the opposite ratio and (b) α3 label is found in large clusters related to mossy cells and basket cells and in medium clusters corresponding to interneurons within the dendritic fields of CA1–3. In the 24-month-old rats as compared with the young animals, the α1 signal is increased more than sevenfold in the dendritic fields and is not significantly changed in perikaryal layers. The α3 signal is reduced about threefold ( p < 0.0001, ANOVA, n = 6) in perikaryal layers, is almost completely absent over the interneurons, basket cells, and mossy cells, and is not significantly changed in dendritic fields. These data indicate age-related, cell- and isoform-specific alterations in pretranslational regulation of Na,K-ATPase α isoforms. The striking changes in the dendritic fields, mossy cells, and GABAergic basket cells and interneurons may constitute early and sensitive markers for age-related alterations in hippocampal function, before cell loss. 相似文献
8.
Electrical impedance measurements made on white spruce, Picea glauca (Moench) Voss, stems were related to shoot free sugar contents and to osmotic, turgor and water potential. During seasonal dormancy induction, there were commensurate increases in free sugar contents, osmotic potential at full turgor and impedance which resulted in linear relationships among these variables. When measured over the course of laboratory drying, impedance increased curvilinearly with decreasing relative water content. There was a linear increase in impedance with decreasing water potential, with a break point coincident with the turgor loss point, possibly attributed to disruption to current flow through broken plasmodesmatal connections between adjacent cells. This technique offers a non-destructive method to measure tissue free sugar content, and therefore, short- and long-term shifts in parameters historically derived from pressure-volume analysis. 相似文献
9.
Summary The location, number and size of the motoneurons innervating the ischiocavernosus muscle, identified by means of horseradish-peroxidase (HRP) retrograde transport, were studied (1) in adult untreated male rats, (2) in adult male rats castrated before puberty, and (3) in adult male rats castrated before puberty and injected with testosterone from the day of castration. After injection of HRP into the ischiocavernosus muscle, labeled motoneurons were found in the dorsolateral and dorsomedial columns of the lamina IX, at the level of L6 and S1 segments of the spinal cord. Morphometric analysis demonstrated that prepubertal castration induces a statistically significant reduction in the somatic and nuclear areas (40% and 35%, respectively, if compared to those of the control rats) of both the dorsolateral and dorsomedial motoneurons, but does not affect their number. The effects of castration are prevented by exogenous testosterone.Preliminary results were presented at the International Conference on Hormones, Brain and Behaviour, Liège, Belgium, August, 1989 相似文献
10.
Purification and partial characterization of an iron regulated outer membrane protein of B. fragilis under non-denaturing conditions 总被引:2,自引:0,他引:2
The CHAPS-PAGE gelsystem we applied gave a good separation of the proteins of Bacteroides fragilis under non-denaturing conditions. We succeeded with preparative CHAPS-PAGE in purifying an iron regulated outer membrane protein (a 44 kDa polypeptide on SDS-PAGE) of B. fragilis. This integral membrane protein proved to be a lipopolysaccharide binding protein with an isoelectric point of approximately pH 5.5. This method of purifying membrane proteins could be an important step in research into the function of membrane proteins. 相似文献