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21.
The furore over the retention of organs at postmortem examination, without adequate consent, has led to a reassessment of the justification for, and circumstances surrounding, the retention of any human material after postmortem examinations and operations. This brings into focus the large amount of human material stored in various archives and museums, much of which is not identifiable and was accumulated many years ago, under unknown circumstances. Such anonymous archival material could be disposed of, used for teaching, used for research, or remain in storage. We argue that there are no ethical grounds for disposing of the material, or for storing it in the absence of a teaching or research rationale. Nevertheless, with stringent safeguards, it can be used even in the absence of consent in research and teaching. Regulations are required to control the storage of all such human material, along the lines of regulations governing anatomy body bequests.  相似文献   
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We report two cases of massive gastrointestinal bleeding due to anterior duodenal ulceration into the cystic artery, with gallbladder infarction as a complication. These cases indicate the potential dangers of laser therapy or embolization in bleeding anterior duodenal ulcers penetrating the cystic artery, as such therapy will arrest blood flow through the cystic artery and may precipitate gallbladder infarction.  相似文献   
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Although blacks appear to be at higher risk for blindness from glaucoma, there is little information available on the epidemiology of this disease in this population. Using a cluster sampling technique with systematic allocation of clusters, the authors conducted a national survey of black individuals 30 years of age and older, in St. Lucia. A total of 1679 individuals underwent a screening examination that included visual acuity, intraocular pressure (IOP) measurement, and cup/disc (C/D) evaluation. Every third person had a screening field on the Humphrey field analyzer. Individuals with either elevated IOP, abnormal C/D ratio, or an abnormal screening visual field were referred for a definitive examination and threshold visual fields. A total of 520 people were referred. Identified by stringent criteria for the diagnosis of glaucoma, which required reliable threshold visual fields abnormal by the mirror image method, 147 individuals had glaucoma for a prevalence of 8.8% in the 30 years of age and older population.  相似文献   
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Using the random cluster sampling technique of the EPI, 210 children of 12-23 months were selected and their vaccination records were examined. Fifty-one (24%) had no vaccination record and 32 of them (15%) were never vaccinated. Using a 'worst' and 'best' estimate analysis it was found that 74-83% had had BCG, 47-56% had had 3 doses of DPT, 48-57% had had 3 doses of polio and 47-56% had had 1 dose of measles vaccine. Between 28-31% of those who received a first dose of DPT or polio vaccine did not receive a third dose. This 'drop-out' effect increased with increasing distance between children's homes and the nearest clinic, as did vaccination coverage in general. As a result of this study, several measures will be undertaken to improve health care delivery in this area. These include the organisation of a mass immunisation campaign later this year, the initiation of more mobile clinics and the training of community health workers.  相似文献   
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In male rats, activity in subdiaphragmatic vagal afferents modulates nociception via an adrenal medulla-dependent mechanism. Because both the vagus and adrenal medullae are sexually dimorphic, we evaluated vagotomy-induced changes in mechanical nociceptive threshold and inflammatory hyperalgesia in female rats and compared them to those previously reported in male rats. We have found that (1) mechanical nociceptive threshold is lower in female rats than in male rats, perhaps because of tonic release of adrenal medullary factors in female rats; (2) mechanical nociceptive threshold in female rats is influenced to a lesser degree by activity in the subdiaphragmatic vagus; (3) vagotomy-induced enhancement of bradykinin hyperalgesia is greater in female rats; (4) in female rats, in contrast to male rats, celiac plus celiac accessory branch vagotomy failed to fully account for the enhancement of bradykinin hyperalgesia in complete subdiaphragmatic vagotomy; and (5) in female rats, in contrast to male rats, adrenal medullectomy plus subdiaphragmatic vagotomy only partially (approximately 30%) reversed the effect of vagotomy on bradykinin hyperalgesia. These findings demonstrate sexual dimorphism in the modulation of both mechanical nociceptive threshold and bradykinin-induced hyperalgesia by activity in subdiaphragmatic vagal afferents as well as the adrenal medulla.  相似文献   
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INTRODUCTION: Changes due to biventricular pacing have been documented by shortening of QRS duration and echocardiography. Compared to normal ventricular activation, the presence of left bundle branch block (LBBB) results in a significant change in cardiac cycle time intervals.Some of these have been used to quantify the underlying cardiac dyssynchrony, assess the effects of biventricular pacing, and guide programming of ventricular pacing devices. This study evaluates a simple noninvasive method using accelerometers attached to the skin to measure cardiac time intervals in biventricularly paced patients. METHODS: Ten patients with biventricular pacemakers previously implanted for congestive heart failure were paced in the AAI mode, then in atrioventricular (AV) sequential mode from the right and left ventricles followed by biventricular pacing. Simultaneous recordings were obtained by 2D, Doppler echocardiography as well as by accelerometers. Similar recordings were obtained from 10 gender, aged matched, normal controls during sinus rhythm. RESULTS: Compared to normals, heart failure patients paced in AAI mode had prolonged isovolumetric contraction time (IVCT), shorter ventricular ejection time (LVET), and prolonged isovolumetric relaxation (IVRT). With biventricular pacing the IVCT decreased, but the LVET and IVRT did not change significantly. There was excellent correlation between the echo and accelerometer-measured intervals. CONCLUSIONS: Shortening of the IVCT measured by an accelerometer is a consistent time interval change due to biventricular pacing that probably reflects more rapid acceleration of left ventricular ejection. The accelerometer may be useful to assess immediate efficacy of biventricular pacing during device implantation and optimize programmable time intervals such as AV and interventricular (VV) delays.  相似文献   
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