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51.
We measured severe acute respiratory syndrome coronavirus 2 spike protein subunits S1/S2 antibodies by using capillary electrophoresis and a chemiluminescence immunoassay for 5,444 active healthcare workers in Italy. Seroprevalence was 6.9% and higher among participants having contact with patients. Seroconversion was not observed in 37/213 previously infected participants.  相似文献   
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We report molecular evidence of Tula virus infection in an immunocompetent patient from Germany who had typical signs of hantavirus disease. Accumulating evidence indicates that Tula virus infection, although often considered nonpathogenic, represents a threat to human health.  相似文献   
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Anomalous coronary arteries occur in as many as 12% of patients with tetralogy of Fallot (TOF). In patients with this condition, pulmonary hypoplasia can be prohibitive in performing a valve-sparing repair, subsequently resulting in various techniques to preserve the anomalous coronary artery. The management strategy is often complex in such a situation. We report on a case of TOF with an anomalous right coronary artery crossing the right ventricular outflow tract, with an unusual course of the right ventricular (RV) branch, which precluded placement of a valved conduit. In this case, we performed a successful repair with mobilization of the anomalous coronary artery and reconstruction of the right ventricular outflow tract with a limited transannular patch.  相似文献   
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A new bioassay for glucagon   总被引:3,自引:3,他引:0       下载免费PDF全文
1 The relaxant action of glucagon has been studied in strips of rabbit renal arteries partially contracted by a low concentration (1 ng/ml) of noradrenaline.

2 The preparation was relaxed in a dose-dependent manner by concentrations of glucagon varying between 25 ng/ml and 420 ng/ml.

3 The relaxant effect of glucagon (0.1 μg/ml ED60) on this preparation was not affected by propranolol (5.0 μg/ml), cimetidine (10 μg/ml), diphenhydramine (10 μg/ml), indomethacin (5.0 μg/ml), phentolamine (1.2 μg/ml), atropine (10 μg/ml) and 8-Leu-ATII (1.0 μg/ml) but was slightly potentiated by Des-Arg9 Leu-OMe8-Bk (25 μg/ml) and indomethacin (50 μg/ml).

4 The dose-response curve to glucagon remained parallel in the presence of papaverine (2.5 μg/ml) but was shifted to the left by a factor of 2.5 to 2.8. Theophylline (250 μg/ml) also potentiated the vascular relaxation induced by glucagon.

5 Insulin (10 μg/ml) did not influence the relaxant effect of glucagon.

6 The removal of the N-terminal amino acid (His) of glucagon reduced by 89% the biological activity of this fragment on the vascular preparation. The removal of the C-terminal amino acids Met-27, Asn-28 and Thr-29 of glucagon resulted in a fragment which was inactive either as an agonist or as an antagonist when tested at concentrations as high as 925 ng/ml.

7 It is concluded that the relaxation of partially contracted strips of rabbit renal arteries by glucagon constitutes a simple, sensitive, relatively specific and reliable bioassay which may be useful for the determination of glucagon in biological materials and for structure-activity relationship studies with this hormone.

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