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991.
A fox circovirus was identified in serum samples from foxes with unexplained neurologic signs by using viral metagenomics. Fox circovirus nucleic acid was localized in histological lesions of the cerebrum by in situ hybridization. Viruses from the family Circoviridae may have neurologic tropism more commonly than previously anticipated.  相似文献   
992.

Background  

The two primary objectives of this study were to the assess consultation load of occupational health physicians (OHPs), and their difficulties and needs with regard to their sickness certification tasks in sick-listed employees with severe medical unexplained physical symptoms (MUPS). Third objective was to determine which disease-, patient-, doctor- and practice-related factors are associated with the difficulties and needs of the OHPs.  相似文献   
993.

Background  

Patients in hospitals and nursing homes are at risk of the development of, often preventable, adverse events (AEs), which threaten patient safety. Guidelines for prevention of many types of AEs are available, however, compliance with these guidelines appears to be lacking. Besides general barriers that inhibit implementation, this non-compliance is associated with the large number of guidelines competing for attention. As implementation of a guideline is time-consuming, it is difficult for organisations to implement all available guidelines. Another problem is lack of feedback about performance using quality indicators of guideline based care and lack of a recognisable, unambiguous system for implementation. A program that allows organisations to implement multiple guidelines simultaneously may facilitate guideline use and thus improve patient safety.  相似文献   
994.
Non–travel-related hepatitis E virus (HEV) genotype 3 infections in persons in the Netherlands may have a zoonotic, foodborne, or water-borne origin. Possible reservoirs for HEV transmission by water, food, and animals were studied. HEV genotype 3/open reading frame 2 sequences were detected in 53% of pig farms, 4% of wild boar feces, and 17% of surface water samples. HEV sequences grouped within 4 genotype 3 clusters, of which 1 is so far unique to the Netherlands. The 2 largest clusters contained 35% and 43% of the animal and environmental sequences and 75% and 6%, respectively, of human HEV sequences obtained from a study on Dutch hepatitis E patients. This finding suggests that infection risk may be also dependent on transmission routes other than the ones currently studied. Besides the route of exposure, virus characteristics may be an important determinant for HEV disease in humans.  相似文献   
995.
Summary In an open triple crossover study in 8 patients with essential hypertension, the possibility has been investigated of whether the blood pressure lowering effect of hydrochlorothiazide 50 mg once daily was attenuated by co-administration for 4 weeks of ibuprofen 400 mg t.i.d., diclofenac 25 mg t.i.d. or sulindac 200 mg b.i.d. Only a slight, statistically non-significant change was found, with the exception of a significant increase in systolic blood pressure after 4 weeks treatment with ibuprofen. There was considerable variation in the blood pressure response during treatment with all three NSAIDs, with slight rises in blood pressure in 13 out of 24 periods. Body weight increased significantly on treatment both with ibuprofen and diclofenac, whereas the increase on sulindac was less and was transient. No significant change was found in various biochemical parameters, including plasma electrolytes, plasma renin activity (PRA), aldosterone, albumin and creatinine, in haematocrit or in the 24-h urinary excretion of sodium and potassium. The sole exception was a decrease in PRA during ibuprofen treatment. From these observations it is concluded that ibuprofen and diclofenac differ from sulindac in their interaction with the diuretic action of hydrochlorothiazide. It appears that all three NSAIDs can safely be combined with hydrochlorothiazide in hypertensive patients, but blood pressure should be monitored carefully when an NSAID are added.  相似文献   
996.
We report a new norovirus GII.4 variant, GII.4 Hong Kong, with low-level circulation in 4 Eurasia countries since mid-2017. Amino acid substitutions in key residues on the virus capsid associated with the emergence of pandemic noroviruses suggest that GII.4 Hong Kong has the potential to become the next pandemic variant.  相似文献   
997.
998.

Background and Purpose

Ca2+ imaging reveals subcellular Ca2+ sparks and global Ca2+ waves/oscillations in vascular smooth muscle. It is well established that Ca2+ sparks can relax arteries, but we have previously reported that sparks can summate to generate Ca2+ waves/oscillations in unpressurized retinal arterioles, leading to constriction. We have extended these studies to test the functional significance of Ca2+ sparks in the generation of myogenic tone in pressurized arterioles.

Experimental Approach

Isolated retinal arterioles (25–40 μm external diameter) were pressurized to 70 mmHg, leading to active constriction. Ca2+ signals were imaged from arteriolar smooth muscle in the same vessels using Fluo4 and confocal laser microscopy.

Key Results

Tone development was associated with an increased frequency of Ca2+ sparks and oscillations. Vasomotion was observed in 40% of arterioles and was associated with synchronization of Ca2+ oscillations, quantifiable as an increased cross-correlation coefficient. Inhibition of Ca2+ sparks with ryanodine, tetracaine, cyclopiazonic acid or nimodipine, or following removal of extracellular Ca2+, resulted in arteriolar relaxation. Cyclopiazonic acid-induced dilatation was associated with decreased Ca2+ sparks and oscillations but with a sustained rise in the mean global cytoplasmic [Ca2+] ([Ca2+]c), as measured using Fura2 and microfluorimetry.

Conclusions and Implications

This study provides direct evidence that Ca2+ sparks can play an excitatory role in pressurized arterioles, promoting myogenic tone. This contrasts with the generally accepted model in which sparks promote relaxation of vascular smooth muscle. Changes in vessel tone in the presence of cyclopiazonic acid correlated more closely with changes in spark and oscillation frequency than global [Ca2+]c, underlining the importance of frequency-modulated signalling in vascular smooth muscle.  相似文献   
999.
ObjectiveTo review the state of knowledge about diagnostic testing for Zika virus infection and identify areas of research needed to address the current gaps in knowledge.MethodsWe made a non-systematic review of the published literature about Zika virus and supplemented this with information from commercial diagnostic test kits and personal communications with researchers in European preparedness networks. The review covered current knowledge about the geographical spread, pathogen characteristics, life cycle and infection kinetics of the virus. The available molecular and serological tests and biosafety issues are described and discussed in the context of the current outbreak strain.FindingsWe identified the following areas of research to address current knowledge gaps: (i) an urgent assessment of the laboratory capacity and capability of countries to detect Zika virus; (ii) rapid and extensive field validation of the available molecular and serological tests in areas with and without Zika virus transmission, with a focus on pregnant women; (iii) monitoring the genomic diversity of circulating Zika virus strains; (iv) prospective studies into the virus infection kinetics, focusing on diagnostic sampling (specimen types, combinations and timings); and (v) developing external quality assessments for molecular and serological testing, including differential diagnosis for similar viruses and symptom clusters. The availability of reagents for diagnostic development (virus strains and antigens, quantified viral ribonucleic acid) needs to be facilitated.ConclusionAn international laboratory response is needed, including preparation of protocols for prospective studies to address the most pressing information needs.  相似文献   
1000.
We obtained the full genome of Middle East respiratory syndrome coronavirus (MERS-CoV) from a camel in Qatar. This virus is highly similar to the human England/Qatar 1 virus isolated in 2012. The MERS-CoV from the camel efficiently replicated in human cells, providing further evidence for the zoonotic potential of MERS-CoV from camels.  相似文献   
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