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31.
Corticosteroids are a mainstay of topical therapy for psoriasis. While efficacious and relatively safe when used carefully, the potential for side effects, notably skin atrophy and adrenal suppression, have been associated with excesses in potency, prolonged or widespread use. The International Psoriasis Council Working Group on Topical Therapy has reviewed the efficacy and safety of topical corticosteroids and recommends strategies for safe, long‐term use of these agents.  相似文献   
32.
The incidence of disturbed sleep is strongly increased in healthy and demented elderly. Age-related alterations in the circadian timing system appear to contribute strongly to these problems. With increasing age, a lack of input to the suprachiasmatic nucleus (SCN), the biological clock of the brain, may accelerate de-activation of neurons involved in the generation of 24-h rhythm or output of this rhythm. This process appears to be reversible, since supplementation of stimuli that impinge on the SCN can re-activate these neurons and ameliorate disturbances in the sleep–wake rhythm.  相似文献   
33.
This study comprised 103 preterm infants with a gestational age less than 33 weeks who were born in Tampere University Hospital and who were followed up to two years of age. Sixty-four perinatal variables were compared to ultrasound findings in the neonatal period and neurologic handicap at the age of two years. Duration of hypocarbia (PCO2 < or = 30 mmHg) during the first 72 h and hyperbilirubinemia (the mean level of serum total bilirubin) at three days of age were independently and significantly related to periventricular leukomalacia, but not directly to cerebral palsy. The only perinatal variables related independently and significantly to cerebral palsy at two years of age were periventricular leukomalacia and ventriculomegaly. According to these results, periventricular leukomalacia was the main predictor of cerebral palsy in preterm infants. In addition to hypocarbia, hyperbilirubinemia may also be involved in the pathogenesis of extensive (severe cystic) periventricular leukomalacia.  相似文献   
34.
This preliminary study was designed to investigate the ability of multiple axial volume three-dimensional fourier transform (3DFT) time-of-flight (TOF) magnetic resonance angiography (MRA) to depict the carotid bifurcation in the early post-carotid endarterectomy period. Five patients underwent intra-operative digital subtraction angiography (DSA) and carotid MRA within 5 days of carotid endarterectomy. An axial volume fast imaging in steady-state precession (FISP) gradient-echo 3DFT TOF carotid MRA technique in this limited series appeared to display accurately the surgically significant abnormalities at the carotid bifurcation after endarterectomy. However, in normal or near-normal intra-operative DSA studies, overestimation of internal carotid artery stenoses was encountered. Postoperative MRA demonstrates potential as a useful non-invasive investigation after carotid endarterectomy but should be interpreted with caution until larger studies become available.  相似文献   
35.
The early clinical experience with a 3-Dimensional Fourier Transform Gradient Echo sequence with fat suppression in the evaluation of breast masses is reported. Ten female patients with breast malignancies were pre-operatively evaluated with this sequence and the results compared with the pathological specimens. The scanning protocol included a noncontrast sequence followed by an immediate post-contrast sequence (completed 4.5 min after intravenous contrast injection) and a delayed sequence. Images were assessed for maximum lesion and parenchymal enhancement, lesion size and additional enhancing abnormalities. In six patients, malignant masses enhanced maximally on the immediate post-contrast sequence with parenchyma enhancing maximally on delayed images. In three cases, there was preferential enhancement of malignant lesions over normal parenchyma but to a similar degree on both post-contrast sequences. In one case, both the lesion and parenchyma enhanced maximally on the delayed sequence. Magnetic resonance assessed lesion size accurately and also detected satellite malignancies in one case. However, lesion grade, associated in situ carcinoma and lymphovascular invasion did not impact on lesion enhancement. In this small series, a contrast-enhanced, fat-suppressed 3-D Gradient Echo Sequence detected breast carcinoma with high sensitivity. The technique holds promise but further evaluation is required.  相似文献   
36.
We explored the effects of microstimulation on target selection by delivering stimulation at different depths within V1 (striate cortex) of the rhesus monkey (Macaca mulatta). Stimulation evoked saccadic eye movements that terminated in the receptive-field location of the activated neurons. The current thresholds for saccade evocation were highest (> or = 30 micro A) in the superficial layers and lowest (< or = 10 micro A) in the deep layers. To study target selection, one visual target was presented in the receptive-field location of the stimulated neurons and a second visual target was presented outside this location. Microstimulation delivered in concert with the appearance of the two targets decreased the probability that a monkey would select the target placed in the receptive-field location when the upper layers of V1 were stimulated, and it increased this probability when the lower layers were stimulated. We suggest that microstimulation of the upper layers of V1 disrupts visual signals from retina en route to higher cortical areas, whereas microstimulation of the lower layers activates V1 efferents that innervate the oculomotor system.  相似文献   
37.
Tehovnik EJ  Slocum WM 《Brain research》2000,877(1):3462-106
It has been reported that training affects motor responses evoked electrically from the dorsomedial frontal cortex (DMFC). Once a monkey had been trained to generate visually-guided saccadic eye movements of a particular size and direction, electrical stimulation of the DMFC elicited saccades of only that size and direction [7]. The current study re-investigates this finding. Monkeys were trained to produce saccadic eye movements to a visual target. After training, electrical stimulation was delivered to the DMFC. It was found that stimulation of the DMFC always evoked saccadic eye movements of the same size and direction before and after training, such that training had little effect on the responses evoked electrically from the DMFC. Differences between the current results and previous results have disclosed new clues as to how the DMFC might be modulated by learning.  相似文献   
38.
Aspergillus endocarditis in chronic granulomatous disease   总被引:2,自引:0,他引:2  
We report the first case, to our knowledge, of Aspergillus endocarditis in chronic granulomatous disease in a patient who also had an atrial septal defect. A diagnosis was made on culture of the organism from the mass despite extensive prior investigation. The presence of distinctive skin lesions as a diagnostic clue of fungaemia is highlighted. Possible advances in diagnosis by detection of fungal cell wall components and in prophylaxis by use of itraconazole are referred to. We conclude that fungal endocarditis should be considered in this condition, especially in the presence of a structural heart defect.  相似文献   
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