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991.
992.
Meningovascular syphilis: CT and MR findings   总被引:4,自引:0,他引:4  
Holland  BA; Perrett  LV; Mills  CM 《Radiology》1986,158(2):439-442
The radiologic findings in three cases of meningovascular syphilis are presented. Angiography demonstrated varying degrees of narrowing and ectasia of the supraclinoid carotid, basilar, and proximal anterior and middle cerebral arteries, as well as distal branches. Computed tomography (CT) showed multifocal infarction with variable enhancement. Similarly, in the one case studied with magnetic resonance (MR), several regions of high signal intensity on T2-weighted sequences were found, which were compatible with foci of ischemia. Although the radiologic findings are nonspecific, the diagnosis of meningovascular syphilis should be considered in patients with vasculitis of uncertain etiology.  相似文献   
993.
994.
Treatment of neurological disorders with intravenous immunoglobulin (IVIg) is an increasing feature of our practice for an expanding range of indications. For some there is evidence of benefit from randomised controlled trials, whereas for others evidence is anecdotal. The relative rarity of some of the disorders means that good randomised control trials will be difficult to deliver. Meanwhile, the treatment is costly and pressure to "do something" in often distressing disorders considerable. This review follows a 1 day meeting of the authors in November 2000 and examines current evidence for the use of IVIg in neurological conditions and comments on mechanisms of action, delivery, safety and tolerability, and health economic issues. Evidence of efficacy has been classified into levels for healthcare interventions (tables 1 and 2).  相似文献   
995.
Silicate clays are frequently added to animal feeds to bind and reduce the bioavailability of mycotoxins in the gastrointestinal tract. However, the bioavailability of trace metals in these clay feed additives has not been thoroughly investigated. Clays that act nonselectively may interact with nutrients, minerals, and other feedborne chemicals to pose significant hidden risks. In this study, a calcium montmorillonite clay (Novasil Plus, NSP) commonly used as an enterosorbent for aflatoxins and a sodium montmorillonite clay (Swy-2) (Source Clay Minerals Repository, Columbia, MO) were examined. Clays were supplemented in the balanced diet of Sprague-Dawley rats during pregnancy at a level of 2% (w/w). Evaluations of toxicity were performed on gestation d 16 and included maternal body weights, maternal feed intakes, litter weights, and embryonic resorptions. Liver, kidneys, tibia, brain, uterus, pooled placentas, and pooled embryonic mass were collected and weighed. Tissues were lyophilized and neutron activation analysis (NAA) was performed. Elements considered by NAA included Al, Ba, Br, Ca, Ce, Co, Cr, Cs, Cu, Dy, Eu, Fe, Hf, K, La, Lu, Mg, Mn, Na, Nd, Ni, Rb, S, Sb, Sc, Se, Sm, Sr, Ta, Tb, Te, Th, Ti, Tl, U, V, Yb, Zn, and Zr. Inductively coupled plasma-mass spectroscopy further confirmed that Al was below detection limits (<0.5 ppm) in the brain. Animals supplemented with either NSP or Swy-2 were similar to controls with respect to toxicity evaluations and metal analysis, with the exception of decreased brain Rb following clay supplementation. Overall, the results of this study suggest that neither NSP nor Swy-2, at relatively high dietary concentrations, influences mineral uptake or utilization in the pregnant rat.  相似文献   
996.
997.
998.
Aim: To explore the feasibility of holding critical incident reviews (CIRs) after patient suicides in general practice and their ability to change practice.

Methods: Thirteen practices were invited to conduct a facilitated CIR on 18 current patient suicides. Next of kin views were sought. All staff attending a CIR were interviewed after the review.

Results: Ten practices reviewed 12 deaths. Twenty six staff attended reviews; all were interviewed. Next of kin contributed to six reviews; only one criticised care. Changes following the reviews included steps to improve internal communication and bereavement support to set up internal CIRs and review prescribing policies. Communications between practices and other agencies were clarified.

Conclusion: Practices were willing to hold CIRs and appreciated the potential positive value but need reassurance that they will not be blamed for suicides, and that the cost in time and resources will be recognised.

  相似文献   
999.
Abstract A numeric scoring system for the assessment of hypoxic ischaemic encephalopathy during the neonatal period was tested. The value of the score in predicting neurodevelopmental outcome at 1 y of age was assessed. Forty-five infants who developed hypoxic ischaemic encephalopathy after birth were studied prospectively. In addition to the hypoxic ischaemic encephalopathy score all but two infants had at least one cranial ultrasound examination. Thirty-five infants were evaluated at 12 months of age by full neurological examination and the Griffiths Scales of Mental Development. Five infants were assessed at an earlier stage, four who died before 6 months of age and one infant who was hospitalized at the time of the 12 month assessment. Twenty-three (58%) of the infants were normal and 17 (42%) were abnormal, 16 with cerebral palsy and one with developmental delay. The hypoxic ischaemic encephalopathy score was highly predictive for outcome. The best correlation with outcome was the peak score; a peak score of 15 or higher had a positive predictive value of 92% and a negative predictive value of 82% for abnormal outcome, with a sensitivity and specificity of 71% and 96%, respectively. For the clinician working in areas where sophisticated technology is unavailable this scoring system will be useful for assessment of infants with hypoxic ischaemic encephalopathy and for prognosis of neurodevelopmental outcome.  相似文献   
1000.
A review of open biopsy for mediastinal masses   总被引:2,自引:0,他引:2  
Objective: To review the recent experience with biopsied mediastinal lesions in children and to assess the impact of recent advances in imaging and surgical techniques on diagnosis. Methodology: The clinical and radiological features of 55 patients who had mediastinal biopsies at The Royal Alexandra Hospital For Children (RAHC) over 15 years were reviewed. Results: Fifty-five patients presented to RAHC between 1978 and 1993 with lesions of the mediastinum requiring biopsy of that site. Thirty-one of the 55 (56%) lesions were malignant. Neurogenic tumours were the most common (40%). In order of frequency the following lesions were found: neuroblastoma (15), teratoma (eight), non- Hodgkin's lymphoma (NHL; eight), enteric cyst/duplication (five), ganglioneuroma (five), bronchogenic cyst (three), ganglioneuroblastoma (two), lymphangioma (two), abscess (two), Hodgkin's lymphoma (HL; two), oesophageal granuloma (one), Langerhan's cell histiocytosis (one), congenital fibromatosis (one). Eighty-two per cent of neurogenic tumours were located in the posterior mediastinum, while 75% of teratomas and 100% lymphoid tumours were located anteriorly. Symptoms were generally unhelpful in establishing a specific diagnosis and in 27% of cases the lesions were discovered incidentally. Physical signs, such as thoracic inlet obstruction and neurological findings, were helpful clinically in localizing lesions within the mediastinum. Chest radiography enabled lesions to be subdivided within the mediastinum. This localization, in combination with the age at presentation, predicted the tissue diagnosis. Computerized tomography (CT) and magnetic resonance imaging (MRI) further defined the lesion and demonstrated involvement of adjacent structures. Histology, however, was essential to distinguish benign from malignant lesions. Conclusions: The clinical presentation of mediastinal masses is often non-specific or incidental. Despite recent advances in imaging technology and biopsy techniques, full histological examination is required to exclude malignancy.  相似文献   
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