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The effect of vaccination with a formalin-inactivated, alum-precipitated (FI), bovine respiratory syncytial virus (BRSV) vaccine on BRSV induced respiratory disease in calves was investigated. Six month old BRSV-naive calves were vaccinated with either a FI, a modified live virus (MLV), or virus antigen negative control vaccine (n = 4 per group). One month after the second vaccination, the calves were aerosol challenged with lung wash from a newborn calf infected with a field isolate of BRSV. Moderate to severe clinical disease occurred in all calves. Calves that received FI vaccine had a significantly earlier (day 2 vs. day 4-5) onset of pyrexia and dyspnea (P < 0.05). Pulmonary lesions, consisting of cranioventral atelectasis and dorsal emphysema, occurred in all groups. Two calves that received MLV, and three that received FI vaccine, had reduced pneumonic lung area relative to controls. Vaccination with the FI vaccine resulted in more rapid onset of clinical disease, but ultimately, reduced pulmonary pathology in most recipients.  相似文献   
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1 The cardiovascular effects of bromocriptine, a dopamine receptor agonist, were investigated in twenty-eight Parkinsonian patients.

2 Bromocriptine caused a significant impairment of postural compensation with a fall in systolic pressure and an absence of the rise in diastolic pressure after standing for 1 min when patients taking active drug were compared to the same patients on placebo. The hypotensive effect persisted for at least 6 weeks of treatment. There was also a significant reduction in supine heart rate.

3 One patient had marked falls in supine and erect blood pressure after a single oral dose of bromocriptine (2.5 mg) and a further patient developed paroxysmal atrial tachyarrhythmias. Both blood pressure and heart rate changes reversed spontaneously after stopping bromocriptine.

4 It is proposed that dopaminergic mechanisms either in the central nervous system or the periphery contribute to cardiovascular regulation in man.

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2,6‐Dicyano‐4‐nitroaniline and 2‐cyano‐4‐nitroaniline (CNNA; 2‐amino‐5‐nitrobenzonitrile) are potent mutagens in the Ames test, even though unsubstituted nitroanilines (NAs) are no more than weak mutagens. These compounds are putative reduction products of many commercial azo dyes, including Disperse Blue 165, Disperse Blue 337, Disperse Red 73, Disperse Red 82, Disperse Violet 33, and Disperse Violet 63. We have examined the mutagenicity in strains TA98 and YG1024 of a series of commercially‐available isomers of CNNA, and some related compounds, to probe the relationship between structure and genotoxic activity in this class of compounds. The potentiating effect of the cyano substituent is seen in many cases; e.g. 2‐amino‐4‐nitrobenzonitrile is a much more potent mutagen than 3‐NA. 2,4‐Dinitrobenzonitrile is also highly mutagenic. Possible mechanisms for the “cyano effect” are considered, with respect to the likely structures of cyanonitroaniline‐DNA adducts and the roles of the enzymes (nitroreductase and acetyl CoA:arylamine N‐acetyltransferase) believed to be involved in the activation of nitroaromatic compounds. Environ. Mol. Mutagen. 59:114–122, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
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The aim of deferred autotransfusion associated with the Cell-Saver system, i.e. the recovery of intraoperative blood loss, is to avoid using external homologous blood products. Transfusion-transmitted diseases and immunisation problems can be avoided: normovolumic haemodilution is an advantage in patients with coronary artery disease and economies can be made in the use of homologous blood. This technique has been in use in Professor Cabrol's department since 1987 with the help of the Blood Transfusion Centre of the Pitié Hospital. The contraindications are unstable angina, severe cardiac failure and anaemia of less than 11 g Hb at the first consultation. A review of the first 65 patients included in the protocol showed that deferred autotransfusion was well tolerated in all cases and that only 10 per cent of patients required transfusion with homologous blood. Autotransfusion associated with the Cell-Saver system is therefore a good method which should be extended to the largest possible number of patients referred for elective cardiac surgery.  相似文献   
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