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排序方式: 共有2751条查询结果,搜索用时 15 毫秒
51.
Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis. 相似文献
52.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age. 相似文献
53.
Tian G Xiang B Dai G Lindsay WG Sun J Shen J Summers R Deslauriers R 《The Journal of thoracic and cardiovascular surgery》2000,120(3):544-551
OBJECTIVE: The present work was designed to study the myocardial perfusion and energy metabolism during retrograde cardioplegia performed with different methods, including deep coronary sinus cardioplegia, coronary sinus orifice cardioplegia, and right atrial cardioplegia. METHODS: Isolated pig hearts were subjected to antegrade cardioplegia, right atrial cardioplegia, deep coronary sinus cardioplegia, and coronary sinus orifice cardioplegia in a random order. Cardioplegic distribution was assessed by T1-weighted magnetic resonance imaging in 1 group of hearts (n = 8). The flow dynamics of cardioplegia were assessed by T2*-weighted imaging in a second group of hearts (n = 8). RESULTS: T1-weighted images revealed an apparent perfusion defect in the posterior wall of the left ventricle, the posterior portion of the interventricular septum, and the right ventricular free wall during deep coronary sinus cardioplegia. The perfusion defect observed in the first 2 regions with deep coronary sinus cardioplegia resolved with coronary sinus orifice cardioplegia. Right atrial cardioplegia provided the most homogeneous perfusion to all regions of the myocardium relative to the other 2 retrograde cardioplegia modalities. T2*-weighted images showed that the 3 retrograde cardioplegia modalities provided similar cardioplegic flow velocities. Localized phosphorus 31 spectroscopy showed that the levels of adenosine triphosphate and phosphocreatine were significantly lower in the posterior wall (adenosine triphosphate, 42.86% +/- 5.91% of its initial value; phosphocreatine, 11.43% +/- 11.3%) than the anterior wall (adenosine triphosphate, 89.19% +/- 8.83%; phosphocreatine, 59.54% +/- 12.58%) of the left ventricle during 70 minutes of normothermic deep coronary sinus cardioplegia. CONCLUSIONS: Deep coronary sinus cardioplegia results in myocardial ischemia in the posterior wall of the left ventricle and the posterior portion of the interventricular septum, as well as in the right ventricular free wall. Coronary sinus orifice cardioplegia improves cardioplegic distribution in these regions. Relative to deep coronary sinus cardioplegia and coronary sinus orifice cardioplegia, right atrial cardioplegia provides the most homogeneous perfusion. 相似文献
54.
Interruption of the contrast column during inspiration can lead to non‐diagnostic CT pulmonary angiograms. The importance of this artefact will increase with more CT studies being performed for pulmonary embolism on multidetector row CT. We describe here an instance of such an artefact and discuss its aetiology. 相似文献
55.
The developmental appearance of a major basilar papilla-specific protein in the chick 总被引:3,自引:0,他引:3
J C Oberholtzer M E Schneider M C Summers J C Saunders F M Matschinsky 《Hearing research》1986,23(2):161-168
The sensory epithelium of the chick cochlea, the basilar papilla, contains a major protein of approximately 23,000 daltons. This protein was as abundant as actin in the papilla, yet could not be found in significant quantities in any other cochlear tissue. The protein appeared at a time in development when other studies have shown that the chick embryo develops peripheral auditory competence. These observations suggest a role for this protein in cochlear function. 相似文献
56.
57.
Tom Seekins William Shunkamolah Michael Bertsche Colin Cowart Jean Ann Summers Amanda Reichard Glen White 《Disability and health journal》2012,5(4):224-232
Purpose/objectiveThe concept of participation is emerging as a gold-standard of outcome measurement in disability and rehabilitation. We aimed to assess the status of methods to measure this new concept.Method/designWe conducted a scoping review and a content analysis to assess the literature on participation.ResultsWe identified 586 articles addressing participation. Seventy-two articles passed all exclusion criteria. Twenty-four articles cited the International Classification of Function as their conceptual foundation. Most studies included individuals with a broad range of impairments (cross disability). Most instruments relied on self-report in a cross-sectional design. We noted three levels of measurement (static, interactional, and dynamic). Few studies reported collecting data on the environment along with participation. Subjective aspects of participation emerged as an important consideration but few articles reported measuring it.ConclusionsThe concept of participation represents more than a “shift from negative to more positive language.” It represents a transformational concept that requires new, dynamic measures collected in context. 相似文献
58.
IntroductionAt many radiotherapy departments around the world, radiation therapists (RTs) undergo performance appraisals annually. Performance appraisals can be confronting and involve complex issues such as feedback, delivering constructive criticism, and positive reinforcement. The focus of this research article was to identify some strengths and weaknesses of general performance appraisal processes and to determine how this process can be streamlined using positive psychology and strength-based development to form a performance management strategy for RTs.MethodsDatabase searches were conducted through ScienceDirect and PubMed for journal articles via the Queensland University of Technology Library website. General article searches were conducted through the online search engine Google. Books were accessed through the University of Southern Queensland Library and Google Scholar. Exclusion criteria included only viewing journal articles with full-text available. Key words searched included positive psychology, strength-based development, performance appraisals, 360° appraisals, and performance management.Results/DiscussionThe total number of journal articles accessed was 61. Because of exclusion criteria, there were 33 articles deemed appropriate to be used. Ultimately, 13 journal articles were referenced among the other sources accessed. Findings included that 360° appraisals generally have a conflicted user base. Findings also included discovering that positive psychology and strength-based development have numerous positive benefits. It was also well documented that performance appraisals should be used as part of an overall performance management strategy for staff. It was also noted that there are many commercially available solutions for performance appraisals.ConclusionsThe literature review identified that 360° appraisals could be integrated into a performance management structure in radiation therapy departments worldwide. Performance management can further be enhanced with the inclusion of positive psychology and strength-based development, which can create a meaningful process that benefits the individual, the team, and the organization. The choice of a new performance management structure is a challenging process but should be pivotal in developing more effective RTs. 相似文献
59.
The intestinal myoelectric effects of four motor-stimulating drugs were compared in conscious dogs. Dogs were fed a standardized 400-kcal meal, and the myoelectric activity was monitored before and after drug administration. Graded doses of metoclopramide, cisapride, bethanechol, and cholecystokinin (CCK) were compared by means of a computer program to identify spike bursts and determine their frequency, duration, and length of migration. Bethanechol and CCK produced the greatest increase in myoelectric activity in terms of spike burst frequency and duration but the least in terms of length of spike burst spread. Metoclopramide had minimal measurable myoelectric effects. Cisapride had the greatest effect on the length of spike burst migration but little effect on spike burst frequency and duration. The results suggest that cisapride is a more efficient prokinetic agent than bethanechol, CCK, or metoclopramide. The greater length of spike burst spread caused by cisapride was associated with a more rapid rate of transit along the monitored segment of bowel when compared with control. This confirms the correlation between length of spike burst spread and propulsive efficiency. 相似文献
60.
KL GOH 《Journal of gastroenterology and hepatology》2004,19(S3):S22-S25
Abstract Gastroesophageal reflux disease (GERD) is a common disease in the West, which now appears to be also increasing in prevalence in the Asian Pacific region. The reasons for this changing epidemiology are two-fold: an increased awareness among doctors and patients, and/or a true increase in the prevalence of the disease. Prevalence rates of reflux esophagitis (RE) of up to 16% and prevalence of GERD symptoms of up to 9% have been reported in the Asian population. However, the frequency of strictures and Barrett's esophagus remain very low. Non-erosive reflux disease (NERD) appears to be the most common form of GERD among Asian patients accounting for 50–70% of cases with GERD. Among Asian patients differences can also be discerned among different ethnic groups. For example, in Malaysia where a multiracial society exists, RE is significantly more common among Indians compared to Chinese and Malays whereas NERD is more frequently seen in the Indian and Malays compared to the Chinese. The reasons for these differences are not known but may indicate both genetic factors and environmental factors peculiar to the particular racial group. GERD has also been increasing in the region demonstrating a time-lag phenomenon compared to the West. Differing predisposition to GERD among different ethnic groups would mean that such an increase would be more prominent among certain racial groups. 相似文献