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21.
In 1985, the Pan American Health Organization adopted the goal of eradication of poliomyelitis from the Americas by 1990. Strategies to accomplish this included high vaccination coverage, aggressive outbreak control, and active surveillance for acute flaccid paralysis (AFP). Although the sensitivity of AFP surveillance for detecting paralytic poliomyelitis cases is high, studies have shown the specificity to be low. In 1990, 2497 notified cases of AFP were investigated in the Americas of which 2146 had stool specimens collected. However, only 18 were confirmed as poliomyelitis by isolation of wild poliovirus from stool specimens, 71 were classified as being compatible with poliomyelitis. Cases of AFP due to causes other than poliomyelitis result in extensive but unnecessary outbreak control measures. To predict, at initial clinical evaluation, the likelihood of future confirmation as a case of poliomyelitis, likelihood ratios (LR) were calculated for different combinations of clinical characteristics of AFP cases (249) from Mexico in 1989 and 1990. The best predictors in a child with AFP were proximal muscle involvement which progressed '4 days together with fever at onset of paralysis, and proximal and unilateral involvement with either fever at onset or paralysis which progressed '4 days. The odds would increase by 12 that the child would eventually be confirmed as poliomyelitis (19), based on a stool culture positive for wild poliovirus (95% confidence interval (CI) 2.6-55.9). A guide for use in the field is proposed whereby local health officials, often with little training in neurological evaluation, can predict at initial clinical examination the likelihood that an AFP case will subsequently be confirmed as poliomyelitis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
22.
目的探讨亲属活体部分小肠移植术后早期并发症的防治。方法为3例短肠综合征患者和1例肠神经节缺失导致小肠无功能患者施行亲属活体部分小肠移植术,供、受者HLA配型均有4个以上抗原相合,供肠均取自回肠末端,长度为(150±10)cm,应用他克莫司、霉酚酸酯及甲泼尼龙预防排斥反应。术后采取抗凝、改善微循环、输注人白蛋白等措施调控患者的出、凝血功能,预防血管吻合口血栓形成和出血,给予法莫替丁或奥美拉唑预防应激性溃疡;给予头孢三代为主的抗生素、更昔洛韦以及氟康唑预防细菌、病毒及真菌感染,并注重对体表易感染部的消毒和护理;术后鼓励患者多下床活动,早期给予谷氨酰胺,尽早将营养支持治疗过渡为肠内营养,以促进移植肠功能的恢复。结果术后3d,1例患者发生肺部鲍曼不动杆菌感染,经抗生素治疗后控制。1例术后5 d移植肠系膜根部出现血肿,手术清除血肿。2例消化道分泌物及大便中发现真菌生长,给予氟康唑治疗后好转。4例在术后20 d左右均发生急性排斥反应,经加大FK506的用量,并以甲泼尼龙冲击治疗后逆转。4例患者,2例获得长期存活,至今分别存活6年8个月和3年2个月,另2例分别于术后5个月、35 d因感染死亡。结论小肠移植术后早期的并发症较多,与小肠的生理结构有关,术后早期并发症的成功防治是临床小肠移植成败的关键。  相似文献   
23.
24.
Influence of subjects' height on the stabilization of posture.   总被引:2,自引:0,他引:2  
In order to investigate the influence of subjects' height in stabilization of body sway, postural EMG reactions were analysed following perturbation of posture during stance on a force measuring platform. Perturbing momenta of different strengths were unexpectedly applied at the back (level of the center of gravity) after being matched to the body weight of each subject. EMG activity of the antagonistic leg muscles and head, hip and ankle joint movements were recorded. There was a close correlation between displacement amplitude at the ankle joint and height of the subject, with the largest displacements in small subjects. The consequence of this relationship was that 1) The compensatory reactions consisted of larger gastrocnemius responses and a stronger coactivation of the tibialis anterior; 2) Momenta of increasing strength resulted in a larger increment of both ankle joint displacement and gastrocnemius EMG responses in small compared to larger subjects. In analogy to tip-toeing movements, it is concluded that the coactivation pattern is typical for stance conditions with a restricted area of support in order to reduce body sway. On the basis of latency measurements it is suggested that the response pattern is induced by proprioceptive information from the impact site of the momentum.  相似文献   
25.
目的研究人脑不同级别胶质瘤中白细胞介素(IL)-6,信号传导和转录活化因子3(STAT3)和血管内皮生长因子(VEGF)的表达,探讨IL-6、STAT3和VEGF与肿瘤病理级别和侵袭性的关系。方法采用免疫组织化学法,检测70例人脑胶质瘤,10例脑膜瘤和5例正常脑组织中IL-6、STAT3和VEGF的表达。结果胶质瘤中IL-6、STAT3和VEGF的表达水平在高级别组(Ⅲ、Ⅳ级)明显高于低级别组(Ⅰ、Ⅱ级),两组间差异有统计学意义(P〈0.01),STAT3的表达与IL-6和VEGF的表达均呈正相关(P〈0.01)。结论IL-6、STAT3和VEGF的表达与胶质瘤的恶性程度有密切关系;且三者协同在胶质瘤发生、发展过程中起重要作用。三者的相关性证实VEGF基因由STAT3蛋白调节,而STAT3又由IL-6刺激活化。  相似文献   
26.
The effect of the cellular immune response by total body irradiation was investigated. The transplant survival (skin grafts) was determined as immune parameter. Donors were colony-bred Wistar rats and recipients were colony-bred Sprague-Dawley rats. The investigations were carried out with irradiated rats and with rats irradiated after thymectomy and/or adrenalectomy as well as with animals without irradiation. A single total-body irradiation (1 and 2 Gy) was administered. The skin graft survival in irradiated rats was significant shorter (radiogenic immunostimulation) than in unirradiated rats; there were no significant differences between the operated (thymectomy and/or adrenalectomy) and not operated animals. Including precedent examinations this radiogenic immunostimulation is caused by a relatively selective inactivation of T-suppressor cells.  相似文献   
27.
Aim:   This paper presents social science understandings of successful aging for a broad audience in multidisciplinary gerontology in Asia–Oceania.
Methods:   The international literature on social science aspects of successful aging is reviewed with a focus on Asia and social improvement.
Results:   New positive approaches to aging research are identifying opportunities for maintaining capacities and well-being over the life course. Successful aging, productive aging, and active aging are key concepts. Increasing life expectancy and fertility control are major social achievements that underpin population aging as the mainstream social transformation facing the world. Asia will be at the forefront of this change and the consequences will vary greatly between cultures, nations, and subgroups within them. Older people generally maintain good quality of life and the capacity to 'age well' is influenced by life-long maturation and emotional, social, and economic resources. Good health can be enhanced through positive actions such as physical activity, good nutrition, and not smoking. Mental capacities can also be improved and maintained throughout old age. In advanced old age, the 'fourth age', the focus turns to ameliorating the effects of loss and to maintaining dignity.
Conclusions:   The social sciences contribute knowledge useful for improving life experiences for older people and aging societies. Population aging is central to national economic development. Public policy and individual action concerning aging can benefit all age groups. To better inform these developments it is important to address the serious shortfall of social science research on aging in the Asia–Oceania region.  相似文献   
28.
Hal Blumenfeld 《Epilepsia》2007,48(S4):18-26
Summary:  Functional magnetic resonance imaging (fMRI) has become a widely used imaging modality in the past decade in both human studies and animal models. Epilepsy presents unique challenges for neuroimaging due to subject movement during seizures, and the need to correlate the timing of often unpredictable seizure events with fMRI data acquisition. These challenges can readily be overcome in animal models of epilepsy. Animal models also provide an opportunity to investigate the fundamental relationships between fMRI signals and brain electrical activity through invasive studies not possible in humans. fMRI studies in animal models of epilepsy can enable us to correctly interpret fMRI signal increases and decreases in human studies, ultimately elucidating specific networks that will be targeted for improved treatment of epilepsy.  相似文献   
29.
The hypercatabolism after massive pediatric burns has been effectively treated with recombinant human growth hormone, an anabolic agent that stimulates protein synthesis and abrogates growth arrest. While experimental studies have shown increased potential for fibrosis induced by growth hormone therapy, adverse effects on human scars have not been investigated. Our aim was to evaluate hypertrophic scar formation in 62 patients randomized to receive injections of 0.05 mg/kg/day of recombinant human growth hormone or placebo, from discharge until 1 year after burn. Scar scales were used to evaluate scar-severity at discharge, 6, 9, 12, and 18-24 months after burn, by three observers blinded to treatment. Computer-assisted planimetry allowed quantification of percentage of hypertrophic scar formation. Types I and III collagens were localized and quantified in scars and normal skin of patients from both groups, using immunohistochemistry with confocal laser microscopy analysis. Insulin-like growth factor-1 blood levels helped assess compliance. Statistical analysis showed that scar hypertrophy significantly increased from 6 to 12 months after injury in both groups, while decreasing at 18-24 months postburn. Types I and III collagens were statistically increased in the reticular layer of scars from both groups when compared to paired normal skin. Insulin-like growth factor-1 was significantly increased in the recombinant human growth factor-treated group. No differences were seen when recombinant human growth factor and control groups were compared using the scar scales, planimetry, or immunohistochemistry. We concluded that recombinant human growth hormone therapy did not adversely affect scar formation and should not contraindicate the administration of recombinant human growth hormone as a therapeutic approach to severely burned children.  相似文献   
30.
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