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111.
L García Menéndez J Galende del Canto J Valentín Cid MA Orejas García 《Canadian Metallurgical Quarterly》1998,198(1):48-49
OBJECTIVE: This was a pilot teleradiology project connecting two secondary KwaZulu-Natal hospitals' radiography departments to a central Durban teaching hospital. The purpose of the study was to assess the usefulness of same-day teleradiology reports to the medical staff and whether such a service changed patient management. DESIGN: After 1 month's service at each hospital, the first 200 teleradiology reports, original radiographs and patients' case notes were reviewed to determine whether any errors in interpretation of the radiographs had been made and whether the reports had changed patient management. RESULTS: The service changed patient management in 10% of cases. Undetected pathology was recognised by the radiologist in 20 patients--pulmonary tuberculosis in 10, spinal tuberculosis in 3, miliary tuberculosis in 2 and fractures in 5. Problems were encountered with transmission of data using the current telephone network, loss of data at the receiving station and the increased workload of the radiographer transmitting the data. CONCLUSIONS: Teleradiology services do make a positive impact on patient management in rural hospitals. However, there are many technical pitfalls that must be avoided in order to establish an effective service. 相似文献
112.
OBJECTIVE: To describe the style and effectiveness (adaptability) of the leadership of coordinators of an autonomous community according to the model of leadership on the ground, analysing its relationship with the work environment. DESIGN: Observational crossover study. SETTING: All the functioning teams in this community. PARTICIPANTS: Medical and nursing coordinators. MEASUREMENTS AND MAIN RESULTS: Hersey and Blanchard's questionnaire on leadership on the ground was employed. This identifies 1) the predominant style (scoring for style 0-12). On the approach of the coordinator to personal relationships and/or task development, it identifies 4 points: direction, persuasion, participation, delegation. 2) Adaptability of the manager (ranging from +24 to -24), based on that the best choice between different options depends on the maturity of the group. To contrast work environment and leadership, a validated questionnaire, adapted to our milieu, was used. Overall reply rate (51 coordinators) was 89.4%. Analysis of styles was: persuasive 5.05 points (SD = 1.25), participatory 4.74 (SD 1.76), directive 1.2 (SD 1.11) and delegating 0.34 (SD 0.68). Adaptability scored 8.38 points (SD = 4.67), and was greater for the nursing coordinators (p < 0.002) without differences for type, place or teaching qualifications. The work environment, both overall and by dimensions, correlated with adaptability, although no relationship was found with leaders' styles. CONCLUSIONS: Leadership adaptability was quite high and greater in nursing. The most prevalent styles were the persuasive and the participatory, more efficacious in teams of average maturity. Theoretical effectiveness was positively related to a better work environment. 相似文献
113.
114.
我国典型天然气藏输导体系研究——以鄂尔多斯盆地苏里格气田为例 总被引:9,自引:1,他引:8
前陆盆地褶皱-冲断带气藏和裂谷盆地气藏油气输导体系以断裂为主,天然气运移方向以垂向为主,运移距离短,输导效率高;而克拉通盆地岩性气藏和前陆盆地斜坡带气藏油气输导体系以砂体为主,油气运移方向为侧向、垂向,运移距离较长,输导效率低。苏里格气田属克拉通盆地岩性气藏,输导体系主要类型为砂体型,也有少量断裂型、砂体-断裂型。砂体型又可进一步分为厚层带状砂体、薄层带状砂体与透镜状砂体等类型。输导体系的输导能力随时间而变化。在200~150 Ma溶蚀作用和断层活动最强,输导体系的输导能力增大到顶峰。在成藏关键时刻(J3—K1),输导体系格架产状西高东低、北高南低,主要输导体系为砂体、断层与裂缝,油气向西北方向运移,输导效率高。在成藏后调整期(K2—Q),输导体系格架大部为东高西低、北高南低,主要输导体系为砂体与裂缝。油气运移效率较低,运移不太明显。 相似文献
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116.
It has been reported that both n-3 and n-6 octadecatrienoic acids can increase hepatic fatty acid oxidation activity. It remains unclear, however, whether different enzymes in fatty acid oxidation show a similar response to n-3 and n-6 octadecatrienoic acids. The activity of hepatic fatty acid oxidation enzymes in rats fed an oil mixture rich in alpha-linolenic acid (18:3n-3) and borage oil rich in gamma-linolenic acid (18:3n-6) was therefore compared to that in rats fed an oil mixture rich in linoleic acid (18:2n-6) and a saturated fat (palm oil) in this study. Linseed oil served as the source of 18:3n-3 for the oil mixture rich in this octadecatrienoic acid and contained 30.6% 18:3n-3 but not 18:3n-6. Borage oil contained 25.7% 18:3n-6 and 4.5% 18:3n-3. Groups of seven rats each were fed diets containing 15% various fats for 15 d. The oxidation rate of palmitoyl-CoA in the peroxisomes was higher in rats fed a fat mixture rich in 18:3n-3 (3.03 nmol/min/mg protein) and borage oil (2.89 nmol/min/mg protein) than in rats fed palm oil (2.08 nmol/min/mg protein) and a fat mixture rich in 18:2n-6 (2.15 nmol/min/mg protein). The mitochondrial palmitoyl-CoA oxidation rate was highest in rats fed a fat mixture rich in 18:3n-3 (1.93 nmol/min/mg protein), but no significant differences in this parameter were seen among the other groups (1.25-1.46 nmol/min/mg protein). Compared to palm oil and fat mixtures rich in 18:2n-6, a fat mixture rich in 18:3n-3 and borage oil significantly increased the hepatic activity of carnitine palmitoyltransferase and acyl-CoA oxidase. Compared to palm oil and a fat mixture rich in 18:2n-6, a fat mixture rich in 18:3n-3, but not fats rich in 18:3n-6, significantly decreased 3-hydroxyacyl-CoA dehydrogenase activity. Compared to palm oil and a fat mixture rich in 18:2n-6, borage oil profoundly decreased mitochondrial acyl-CoA dehydrogenase activity, but a fat mixture rich in 18:3n-3 increased it. 2,4-Dienoyl-CoA reductase activity was significantly lower in rats fed palm oil than in other groups. Compared to other fats, borage oil significantly increased delt3,delta2-enoyl-CoA isomerase activity. Activity was also significantly higher in rats fed 18:2n-6 oil than in those fed palm oil. It was confirmed that both dietary 18:3n-6 and 18:3n-3 increased fatty acid oxidation activity in the liver. These two dietary octadecatrienoic acids differ considerably, however, in how they affect individual fatty acid oxidation enzymes. 相似文献
117.
Valsalva minimal leak point pressure: a useful approximation to type III female urinary incontinence
L Prieto Chaparro F García López F Lloréns Martínez E de Nova Sánchez JA Galán Llopis C Fernández Puentes V Menéndez López 《Canadian Metallurgical Quarterly》1998,51(8):783-789
Aging is associated with changes in physical characteristics and decline of many physiological functions. The aging process have been described by various theories, in particular the free radical theory of aging has received widespread attention. It has been accepted that the oxidative stress or damage induced by free radicals is related to aging. In this study, we determined the serum concentration of lipid peroxide and antioxidant as biomarker for aging. Healthy subjects were classified into 3 groups, elderly (65-), middle-aged (40-64) and young group (20-39). Findings in the elderly were as follows: 1. Lipid peroxides in the elderly group were significantly higher than those in the young group. 2. Preventive antioxidant concentrations of superoxide dismutase, glutathione peroxidase and albumin were lower than those in the young group, but ceruloplasmin values increased and catalase activity was unchanged. 3. The total antioxidant capacity of serum was slightly decreased. 4. Superoxide generation by neutrophils while resting was significantly higher in the young group. 相似文献
118.
用于旋转机械故障诊断的一种张量增强型前向神经网络模型 总被引:2,自引:0,他引:2
在多层前向神经网络模型的研究基础上,提出了基于张量的增强型前向神经网络诊断模型,以实现在已知输入模式不变的情况下,增强原始模式的表达,从而提高了诊断的精度。试验结果表明,本模型对工程应用具有较高的实用价值。 相似文献
119.
大张坨储气库储层注采渗流特征研究 总被引:5,自引:1,他引:4
大张坨地下储气库是陕京输气管道的配套工程,保障天然气的调峰需要和供气安全,是由一个正在进行循环注气开发的凝析气藏改建而成的。为了保证地下储气库的长期使用寿命,需要研究在反复强注强采过程中气层的孔渗变化情况,为此开展了不同覆压条件下的孔隙度和渗透率反复测试实验和气水往复驱替实验。不同覆压孔渗测试实验结果证实,在储气库运行压力变化范围内孔隙度和渗透率变化幅度不大,而且这种变化基本上是可逆的。气水往复驱替实验结果证实,在气水两相反复驱替过程中气相有效渗透率呈下降的趋势,而且随着驱替次数的增加,两相共流区缩小,残余水下的气相渗透率和残余气下的水相渗透率都呈下降趋势。因此,只要将注采井选择在气藏构造的高部位,就能控制气水两相反复驱替造成的储层渗透率降低,这样不仅能够实现少井高产的目的,而且能够保证该储气库正常使用。这得到储气库运行实践的佐证。 相似文献
120.