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We report a case of conjunctival tuberculosis in a trainee microbiologist caused by direct inoculation. The resident strain was analyzed by DNA fingerprinting, and an identical pattern was found in an isolate from sputum handled by the resident. After 6 months of treatment, the patient was cured.  相似文献   
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Phasic oculomotor activity is one of the features identifying rapid eye movement (REM) sleep. Recently, it has been shown in cats that, despite bursts of complex two-component rapid eye movements, the eyes tend to maintain a nasal and downward rotation during REM sleep. Although the function of eye movements during sleep remains elusive, it is important to know whether the characteristics of eye movements during sleep are species-specific in mammals. In this work, quantitative characteristics of eye movements, recorded by the scleral search coil technique, were studied during wakefulness and sleep in rats. During wakefulness, rats performed conjugated saccades at a very low rate and some eye movements associated to blinking and gnawing. Throughout non-REM sleep, eye movements were slow, mostly unconjugated and the eyes maintained a divergence in the horizontal plane. The beginning of REM sleep was characterized by a convergence and downward rotation of the eyes, which tended to persist until the end of REM sleep. Rapid eye movements, isolated and monocular at the beginning, became complex and organized in high-frequency bursts. These results demonstrate that, despite the difference in extraocular anatomy and visuomotor strategies between frontal- and lateral-eyed species, eye movements during REM sleep in rats are very similar to those described in cats. This suggests that the mechanisms generating eye movements during REM sleep are largely conserved in mammals.  相似文献   
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Introduction

Although the diagnosis of brain death (BD) is usually based on clinical criteria, in sedated patients, ancillary techniques are needed. This study was designed to assess the accuracy of cerebral multislice computed tomographic angiography (CTA) and CT perfusion (CTP) in diagnosing BD.

Methods

Prospective observational study in 27 BD patients.

Results

All patients were diagnosed as BD based on clinical and electroencephalogram findings. After BD diagnosis, CTP was performed followed by 64-detector multislice CTA from the aortic arch to the vertex. Images were reconstructed from 0.5 mm sections. In 24 patients, a lack of cerebral blood flow (CBF) was detected by CTP, and CTA revealed luminal narrowing of the internal carotid artery in the neck and absence of anterior and posterior intracranial circulation (sensitivity 89%). CTA detected CBF exclusively in extracranial portions of the internal carotid and vertebral arteries. Two patients with anoxic brain injury and decompressive craniectomy showed CBF in the CTA such that the CTP results were considered false negatives, given BD had been confirmed by clinical and EEG findings, along with evoked potentials. In one clinically BD patient, in whom an alpha rhythm was detected in the electroencephalogram, CBF was only observed in the intracranial internal carotid with no posterior circulation noted. This patient was therefore considered exclusively brain stem dead.

Conclusions

The radiological protocol used shows a high sensitivity and excellent specificity for detecting the cerebral circulatory arrest that accompanies BD. As a rapid, non-invasive, and widely available technique it is a promising alternative to conventional 4-vessel angiography.  相似文献   
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