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51.
Summary A simple technique of stereotactic craniotomy and intraoperative lesion localisation that uses the Brown-Robert-Wells (BRW) stereotactic frame is presented. The method optimises craniotomy placement and facilitates localisation of small intracerebral lesions. Using the system, 16 patients have had resection of intracranial neoplasms from deep and/or eloquent areas of the brain with no neurological morbidity. 相似文献
52.
通过42例重型肺心病、7例轻型肺心病、16例肺心病伴发冠心病患者和30例正常人在静息状态下的左右心脏射血分数及其临床资料的分析表明,重型肺心病患者在病情的急性发作期,存在有不同程度的左心功能不全,而轻型肺心病患者则无左心功能不全的表现。表明慢性肺心病仅在病程晚期,才由以右心为主的疾病发展成为全心病。本文还对重型肺心病与肺心病伴发冠心病患者的左心功能进行比较,结果表明,肺心病伴发冠心病患者左室功能受损程度更为明显,双重病因导致的左室功能减退,常造成心肌更严重的损害而且不容易恢复。 相似文献
53.
Hannie G. A. Bouman Monique L. A. Broekhuizen A. Mieke J. Baasten Adriana C. Gittenberger-De Groot Arnold C. G. Wenink 《Anatomical record (Hoboken, N.J. : 2007)》1995,243(1):101-108
Background: In a recently developed chick model the teratogen retinoic acid has appeared to induce a spectrum of double outlet right ventricle, which needs further detailed evaluation. It is known that retionic acid is able to induce cardiac malformations. Although the exact mechanism is not known, an interaction with neural crest cell function is thought to exist. Methods: After treatment with 1 μg all-trans retinoic acid at Hamburger and Hamilton stage 15 and reincubation until stage 34 of development 41 chicken embryos were evaluated macroscopically and microscopically, supported by graphic reconstructions. These retinoic acid treated embryos were compared with a control group (n = 8). Results: The retinoic acid treated embryos could be divided in three groups. Group 1 (23/41) had an intact septum, group 2 (11/41) had an isolated ventricular septal defect (VSD), and group 3 (7/41) had a double outlet right ventricle (DORV). Besides, in the group with an intact septum 11 hearts showed an abnormal course of the subaortic outflow tract. In the group with DORV a straddling tricuspid orifice (7/8) and a double inlet left ventricle (1/8) could be distinguished. Considering the external contour, the hearts in the DORV group all showed a dextroposed arterial pole. Malformed pharyngeal arch arteries were found in all three groups (11/41) and with a great diversity. Conclusions: The present cardiac malformations in the chicken as a result of retinoic acid treatment are part of a continuous spectrum, varying from hearts with an intact ventricular septum and a normal course of the subaortic outflow tract to a double outlet right ventricle with a straddling tricuspid orifice or even a double inlet left ventricle. A remarkable observation in this spectrum concerns the correlation of malformations of the inflow and outflow tracts, which is explained as a cardiac looping disturbance. The disturbance of the looping process seems to lead to malalignment of septal components, although, in the chick, retinoic acid does not in general interfere with the formation of these septal components themselves. © 1995 Wiley-Liss, Inc. 相似文献
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55.
Dennis J. Murphy 《Drug development research》1994,32(4):237-246
The known effects of drugs from a variety of pharmacologic/therapeutic classes on the respiratory system and worldwide regulatory requirements support the need for conducting respiratory evaluations in safety pharmacology. The objective of these studies is to evaluate the potential for drugs to cause secondary pharmacologic or toxicologic effects that influence respiratory function. Changes in respiratory function can result either from alterations in the pumping apparatus that controls the pattern of pulmonary ventilation or from changes in the mechanical properties of the lung that determine the transpulmonary pressures (work) required for lung inflation and deflation. Defects in the pumping apparatus are classified as hypo- or hyperventilation syndromes and are evaluated by examining ventilatory parameters in a conscious animal model. The ventilatory parameters include respiratory rate, tidal volume, minute volume, peak (or mean) inspiratory flow, peak (or mean) expiratory flow, and fractional inspiratory time. Defects in mechanical properties of the lung are classified as obstructive or restrictive disorders and can be evaluated in animal models by performing flow-volume and pressure-volume maneuvers, respectively. The parameters used to detect airway obstruction include peak expiratory flow, forced expiratory flow at 25 and 75% of forced vital capacity, and a timed forced expiratory volume, while the parameters used to detect lung restriction include total lung capacity, inspiratory capacity, functional residual capacity, and compliance. Measurement of dynamic lung resistance and compliance, obtained continuously during tidal breathing, is an alternative method for evaluating obstructive and restrictive disorders, respectively, and is used when the response to drug treatment is expected to be immediate (within minutes post-dose). The species used in the safety pharmacology studies conducted in our laboratory are the same as those used in toxicology studies since pharmacokinetic and toxicologic/pathologic data are available in these species. These data can be used to help select test measurement intervals and doses and to aid in the interpretation of functional change. The techniques and procedures for measuring respiratory function parameters are well established in guinea pigs, rats, and dogs. 相似文献
56.
整体护理改善护患关系的体会 总被引:2,自引:2,他引:0
整体护理的实施,重塑了护士的职业价值观,增加了护患之间的接触。护士能够在自己的专业范围内积极主动地解决病人的问题,挖掘了护理人员的自身潜力,加深了护患交流,使护患关系明显改善。 相似文献
57.
101例尿毒症相关性肺水肿的特殊护理措施 总被引:2,自引:0,他引:2
目的 探讨尿毒症相关性肺水肿的特殊护理措施。方法 对尿毒症相关性肺水肿的护理除常规护理措施外,应做到以下几点特殊护理:①密切观察血压、血氧饱和度、近期尿量变化;②有效控制血压;③采取不同的透析方式适时适量透析超滤、加强透析中的护理;④改善全身营养状况,防止肺部感染;⑤牢记护理程序体位-吸氧-血管扩张药-血液透析;⑥严格控制入量。结果 101例病人中抢救成功84例,死亡13例,自动出院3例。结论 采取治疗和特殊护理对抢救尿毒症相关性肺水肿患者有较好效果。 相似文献
58.
Carole Roan Gresenz Jeannette Rogowski José J. Escarce 《Health services research》2007,42(1P1):239-264
Objective. To quantify the relationship between utilization of care among the uninsured and the structure of the local health care market and safety net.
Data Sources/Study Setting. Nationally representative data from the 1996 to 2000 waves of the Medical Expenditure Panel Survey (MEPS) linked to data from multiple secondary sources.
Study Design. We separately analyze outpatient care utilization and whether an individual incurred any medical expenditure among uninsured adults living in urban and rural areas. Safety net measures include distances between each individual and the nearest safety net providers as well as a measure of capacity based on local government and hospital health expenditures. Other covariates include the managed care presence in the local health care market, the percentage of individuals who are uninsured in the area, and local primary care physician supply. We simulate utilization using standardized predictions.
Principal Findings. Distances between the rural uninsured and safety net providers are significantly associated with utilization. In urban areas, we find that the percentage of individuals in the area who are uninsured, the pervasiveness and competitiveness of managed care, the primary care physician supply, and safety net capacity have a significant relationship with health care utilization.
Conclusions. Facilitating transport to safety net providers and increasing the number of such providers are likely to increase utilization of care among the rural uninsured. Our findings for urban areas suggest that the uninsured living in areas where managed care presence is substantial, and especially where managed care competition is limited, could be a target for policies to improve the ability of the uninsured to obtain care. Policies oriented toward enhancing funding for the safety net and increasing the capacity of safety net providers are likely to be important to ensuring the urban uninsured are able to obtain health care. 相似文献
Data Sources/Study Setting. Nationally representative data from the 1996 to 2000 waves of the Medical Expenditure Panel Survey (MEPS) linked to data from multiple secondary sources.
Study Design. We separately analyze outpatient care utilization and whether an individual incurred any medical expenditure among uninsured adults living in urban and rural areas. Safety net measures include distances between each individual and the nearest safety net providers as well as a measure of capacity based on local government and hospital health expenditures. Other covariates include the managed care presence in the local health care market, the percentage of individuals who are uninsured in the area, and local primary care physician supply. We simulate utilization using standardized predictions.
Principal Findings. Distances between the rural uninsured and safety net providers are significantly associated with utilization. In urban areas, we find that the percentage of individuals in the area who are uninsured, the pervasiveness and competitiveness of managed care, the primary care physician supply, and safety net capacity have a significant relationship with health care utilization.
Conclusions. Facilitating transport to safety net providers and increasing the number of such providers are likely to increase utilization of care among the rural uninsured. Our findings for urban areas suggest that the uninsured living in areas where managed care presence is substantial, and especially where managed care competition is limited, could be a target for policies to improve the ability of the uninsured to obtain care. Policies oriented toward enhancing funding for the safety net and increasing the capacity of safety net providers are likely to be important to ensuring the urban uninsured are able to obtain health care. 相似文献
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