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A 42-year-old male with a history of chronic aortic valve disease and urethra stenosis, was admitted with fever, dysuria, and vomiting. Escherichia coli (E. coli) was cultured from blood and urine. Repeated transesophageal echocardiographic studies performed during the early phase of the hospitalization did not exclude the possibility of infective endocarditis. A definite diagnosis was, however, not established until 6 weeks after admission. At that time a large paravalvular aortic abscess cavity had developed and urgent surgery was necessary. A possible explanation for the delayed diagnostic evaluation was the low level of suspicion, as the septicemia was believed to originate from the urinary tract, without involvement of other organs. The possibility of endocarditis due to E. coli should be considered, especially in subjects with underlying cardiac valve disease, despite an alternative source of septicemia and despite the rarity of this condition. Frequent echocardiographic studies are recommended since extensive tissue destruction may occur without any striking symptoms.  相似文献   
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Purpose: To study the occurrence and distribution of the neuropeptide pituitary adenylate cyclase-activating peptide (PACAP) in ocular and orbital structures of the cat. Methods: Immunocytochemistry to localize PACAP and double immunostaining to detect co-localization of PACAP with other neuropeptides. Results: Numerous PACAP-immunoreactive nerve fibers were observed in the lacrimal gland, choroid and retroocular arteries. There was a sparse supply of PACAP-containing nerve fibers in the iris, ciliary body and conjunctiva. Subpopulations of PACAP-containing nerve fibers stored vasoactive intestinal peptide (VIP) or calcitonin gene-related peptide (CGRP). Around 10% of the ganglion cells in the sphenopalatine ganglion harbored PACAP immunoreactivity. In the trigeminal ganglion around 5% of the neuronal cell bodies and in the ciliary ganglion only occasional ganglion cells contained PACAP immunoreactivity. PACAP immunoreactivity co-localized with VIP in the sphenopalatine ganglion and with CGRP in the trigeminal ganglion. Conclusion: PACAP-containing nerves in the eye and associated structures demonstrate a distribution pattern resembling that of VIP. Subpopulations of nerve fibers containing PACAP immunoreactivity store VIP or CGRP immunoreactivity. Neuronal PACAP in the eye and orbit may take part in regulation of smooth muscle tone, glandular secretion and sensory processing.  相似文献   
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The purpose of this study was to define the cumulative incidence of pregnancy rhinitis, and to study whether smoking, asthma, hayfever or month of conception are risk factors. A questionnaire was delivered during 1 year in 10 antenatal care centers in one Swedish county. Questions were asked by midwives on the ordinary check-up visits throughout pregnancy. Five centers with response rates of 70% or more, including 599 women, were evaluated. The cumulative incidence of pregnancy rhinitis was 22%. Smokers had a significantly increased incidence with a relative risk enhancement of 69%, whereas hayfever, asthma, and month of conception had no statistically significant influence on incidence. Pregnancy rhinitis was shown to appear at any time during gestation.  相似文献   
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The dorsal medial frontal cortex (dMFC) is highly active during choice behavior. Though many models have been proposed to explain dMFC function, the conflict monitoring model is the most influential. It posits that dMFC is primarily involved in detecting interference between competing responses thus signaling the need for control. It accurately predicts increased neural activity and response time (RT) for incompatible (high-interference) vs. compatible (low-interference) decisions. However, it has been shown that neural activity can increase with time on task, even when no decisions are made. Thus, the greater dMFC activity on incompatible trials may stem from longer RTs rather than response conflict. This study shows that (1) the conflict monitoring model fails to predict the relationship between error likelihood and RT, and (2) the dMFC activity is not sensitive to congruency, error likelihood, or response conflict, but is monotonically related to time on task.  相似文献   
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