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1.
Granulocytic ehrlichiosis in two dogs in Switzerland.   总被引:11,自引:5,他引:6       下载免费PDF全文
This case report describes two dogs with granulocytic ehrlichiosis. Dog 1 was a male Labrador retriever with clinical signs of lymphosarcoma. Dog 2 was a female Airedale terrier, whose clinical signs included apathy, pyrexia, diarrhea, and abdominal pain. Examination of blood smears revealed Ehrlichia organisms in the neutrophils of both dogs. There was thrombocytopenia in both dogs, and dog 2 also had leukopenia. In both dogs, bands of identical length were amplified from DNA of leukocytes via nested PCR. The bands had identical nucleotide sequences, which differed from the gene sequences of Ehrlichia equi and E. phagocytophila in three and two positions, respectively. Interestingly, the nucleotide sequence of the 16S rRNA was 100% homologous to that of a human granulocytic ehrlichia.  相似文献   
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Serum samples from 996 dogs in Switzerland were examined for antibodies to Ehrlichia canis and to the agent causing canine granulocytic ehrlichiosis (CGE). Ehrlichiosis, borreliosis, and systemic illness not associated with ticks were suspected in 75, 122, and 157 of these dogs, respectively. The remainder of the serum samples were obtained from clinically healthy dogs which resided north (n = 235) or south (n = 407) of the Alps. The serum samples were tested by an indirect immunofluorescence technique for antibodies to the two agents incriminated, E. canis and Ehrlichia phagocytophila, a surrogate marker of the agent of CGE. Twenty-two of 996 (2.2%) serum samples had antibodies to E. canis and were distributed as follows: 20 of 75 (26.7%) samples from dogs suspected of having ehrlichiosis, 1 of 122 (0.8%) from dogs suspected of having borreliosis, and 1 of 407 (0.2%) from healthy dogs which resided south of the Alps. Of the 75 (7.5%) serum samples that had antibodies to E. phagocytophila, significantly more samples were from ill dogs than from healthy dogs. Among the sera from healthy dogs, antibodies to E. phagocytophila were significantly more prevalent in the north. Because seropositive dogs had a history of travel outside Switzerland and because Rhipicephalus sanguineus is found exclusively south of the Alps, it was presumed that, in contrast to the agent of CGE, E. canis is not indigenous to Switzerland.  相似文献   
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Identification of quinolinic acid in rat and human brain tissue   总被引:20,自引:0,他引:20  
An analytical technique for the determination of the excitotoxic compound quinolinic acid (2,3-pyridine dicarboxylic acid) in brain tissue has been developed. Following sample prepurification by ion exchange and high pressure liquid chromatography, quinolinic acid is converted to the dihexafluoroisopropyl ester and the derivative is analyzed by mass fragmentography. Using the present technique quinolinic acid has been identified in both rat and human brain tissue.  相似文献   
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Calcium influx through voltage-activated calcium channels may play a crucial role in the propagation and maintenance of seizure activity. We have examined the contribution of various types of calcium currents to epileptogenesis by studying the effects of various calcium channel blockers on epileptiform activity. N-methyl-d-aspartate receptor-mediated epileptiform activity was induced by removal of magnesium ions superfusing the cortex, or by low-frequency stimulation of the underlying white matter. CoCl2, CdCl2 and omega-conotoxin, acting at the N- and L-type calcium channels, significantly reduced epileptiform activity. L-channel antagonists nifedipine and verapamil, and the agonist BAY K 8644, increased spontaneous bursting in cortical wedges, but had no effect upon evoked activity. The T-channel blocker NiCl2 had variable effects on epileptiform activity, whereas phenytoin consistently reduced such activity. These results suggest that calcium influx underlying epileptiform activity in the rat neocortex may occur at least partially via the activation of the N-type calcium channel. However, contributions from other calcium channel types cannot be excluded.  相似文献   
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Social roles dominate people's lives, and people largely perceive themselves and each other in terms of their roles. The value people attribute to various social roles tends to decisively shape their behavior toward persons whom they see in valued or devalued roles. Those in valued roles tend to be treated well and those in devalued roles, ill. The most current and recently revised version of the Social Role Valorization (SRV) schema is presented in condensed form, showing how social role theory can be recruited for designing very powerful practical measures to pursue valued roles for mentally retarded and other persons or classes at risk of social or even societal devaluation, to upgrade the perceived value of the roles such persons already occupy, and/or to extricate such persons from devalued roles.  相似文献   
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Hyperoxia during T2*-weighted magnetic resonance imaging (oxygen challenge imaging (OCI)) causes T2*-weighted signal change that is dependent on cerebral blood volume (CBV) and oxygen extraction fraction (OEF). Crossed cerebellar diaschisis (CCD), where CBV is reduced but OEF is maintained, may be used to understand the relative contributions of OEF and CBV to OCI results. In subjects with large hemispheric strokes, OCI showed reduced signal change in the contralesional cerebellum (P=0.027, n=12). This was associated with reduced CBV in contralesional cerebellum (P=0.039, n=9). CCD may be a useful model to determine the relative contribution of CBV to signal change measured by OCI.  相似文献   
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ObjectiveTo determine the prevalence, sex-age related intensity of urinary schistosomiasis and to compare such parameters among rural school children and rural farmers in selected communities in Obollo-Eke located in Southeast, Nigeria.MethodsA cross-sectional survey involving 1 337 school children and farmers was conducted in Obollo-Eke community between September 2006 and July 2007. Demographic data of subjects was collected using a questionnaire prepared for this purpose. Urine samples were collected and examined for haematuria and ova of Schistosoma haematobium (S. haematobium) using Medi-test Combi 9 and sedimentation technique respectively.ResultsThe prevalence of urinary schistosomiasis based on microscopic examination of the urine sediment for the ova of S. haematobium was 17.5% while the prevalence of haematuria was 15.6%. Infection intensity varied from light to heavy. In general, the prevalence was higher among males (20.8%) than females (14.6%; P>0.05) and was slightly higher among primary school children (18.0%; n=762) than farmers (16.9%; n=575; P>0.05). The age-specific prevalence of schistosomiasis among the study subjects ranged from 8.3% to 21.2% in 0-5 years and 11-15 years age groups respectively.ConclusionsHaematuria and mean egg/10 mL urine (r = 0.95; P<0.01) showed that both procedures are reliable for the diagnosis of the disease and can be used to ascertain the prevalence of the disease in any community. The comparative analysis of urinary bilharziasis among primary school children and rural farmers demonstrated that the infection is moderately high in these two risk population groups at Obollo-Eke. A robust intervention strategy is clearly needed.  相似文献   
10.
Abstract

Catheters are widely used and play an important role in medicine. However, catheter-associated infection is prevalent even under stringent sterile conditions. Biofilms are formed when bacteria populate the surfaces of catheters. This makes the biofilm resistant to antibiotics. Hence, it is imperative for there to be an inherently antifouling and anti-bacterial catheter to mitigate the formation of biofilm. This paper aims to outline the synthesis of non-leachable anti-biofilm and anti-bacterial cationic film coatings through direct polymerization using supplemental activator and reducing agent surface initiated atom transfer radical polymerization (SARA SI-ATRP). Three crosslinked cationic coatings comprising of Diallyl dimethyl ammonium chloride (DADMAC), or ε-poly-L-lysine HCl methacrylic acid (EPL-MA) together with a crosslinker (polyethylene glycol dimethacrylate, PEGDMA) were investigated. These non-leachable covalently linked coatings with DADMAC can achieve more than 2 log reduction (99.0%) with Methicillin-resistant Staphylococcus aureus (MRSA) and 1.25 log reduction (94.4%) with Vancomycin resistant Enterococcus (VRE) in in vitro studies.  相似文献   
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