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排序方式: 共有2736条查询结果,搜索用时 13 毫秒
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Smart cars, smart highways 总被引:2,自引:0,他引:2
Advanced electronics is being used to unclog the transportation network and allow private vehicles, trucks, buses and trains to move further faster. already a range of technologies and ideas have been explored, deployed, and tested as part of the Intelligent Vehicle Highway System programs in the United States and Japan, and in the Road Transport Informatics program in Europe. The authors describe how these latest electronics for automobiles and roadways herald far fewer traffic jams, greater safety, and perhaps even a decline in pollution 相似文献
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This retrospective study examined the clinical course of 18 prepubertal boys (aged 6 to 12) who had dual diagnoses of attention deficit hyperactivity disorder and conduct disorder and who received clonidine on an inpatient basis after failed trials of conventional drug therapy, consisting predominantly of psychostimulants. The effects of clonidine were assessed during inpatient treatment and after discharge at intervals of 1 to 2 months. Eleven (61%) of the children had marked improvement as measured by clinical impression. Transient sedation lasting 2 to 3 days occurred after initial administration or dosage increase; otherwise, clonidine was well tolerated. Our findings suggest that clonidine may prove to be an alternative treatment of comorbid attention deficit hyperactivity disorder and conduct disorder. 相似文献
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SJ McPherson RN Gibson NA Collier TG Speer ND Sherson 《Canadian Metallurgical Quarterly》1998,206(3):665-672
Ancylostoma duodenale is still the dominant hookworm species in the Mediterranean area, India, China and Japan. In the present study, biopsied materials were taken from the small intestine of 30 patients infected only with A. duodenale and 12 cross matched controls. The results showed some pathological changes in severely infected cases. However, normal or insignificant changes were seen in the enzymatic activity of the intestinal mucosa. 相似文献
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G. R. Collier F. McL Collier A. Sanigorski K. Walder D. Cameron-Smith A. J. Sinclair 《Lipids》1997,32(3):317-322
Recently it has been postulated that membrane fatty acid composition may be involved in the pathogenesis of insulin resistance
and non-insulin dependent diabetes mellitus (NIDDM). The aim of this study was to determine whether alterations in tissue
phospholipid (PL) fatty acids are present in hyperglycemic and hyperinsulinemic Psammomys obesus. On a native diet of salt bush, P. obesus (Israeli sand rat) remains lean and free of diabetes; however, when placed on a normal laboratory chow, a significant proportion
of these animals develops a number of metabolic disorders associated with NIDDM, providing an ideal animal model of obesity
and NIDDM. Four groups of mature P. obesus were studied: group A; normoglycemic and normoinsulinemic; group B: normoglycemic and hyperinsulinemic; group C: hyperglycemic
and hyperinsulinemic; and group D: hyperglycemic hypoinsulinemic. In liver and red gastrocnemius muscle, there were no significant
differences between groups, A, B, and in fatty acid composition of PL. Minor differences in individual fatty acids were demonstrated
in group D animals (increased liver 20∶4n-6 and increased muscle 22∶5n-3); however, the unsaturation indices in liver and
muscle were not significantly different between any of the groups. In considering that the minor changes in group D animals
were not demonstrated in hyperinsulinemic group B animals or hyperglycemic, hyperinsulinemic group C animals, it is likely
that the differences in group D animals were secondary to the more severe disturbances in glucose homeostasis and hypoinsulinemia
present in these animals. The results of this study suggest that in this rodent diabetic model significant disturbances in
glucose homeostasis and hyperinsulinemia may develop independently of changes in tissue fatty acid composition. 相似文献
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DI Blyth MS Pedrick TJ Savage H Bright JE Beesley S Sanjar 《Canadian Metallurgical Quarterly》1998,19(1):38-54
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OBJECTIVE: Primary aortoenteric fistula is a rare disorder of which only four patients have been reported in the Dutch literature so far. The objective of our study was to obtain more realistic figures on the incidence of this condition, with data on the clinical presentation, diagnostic procedures, treatment and results in a group of patients not previously reported as "case histories". METHODS: A questionnaire was sent to all surgical clinics in The Netherlands. Out of 180 questionnaires, 102 have been returned reporting 27 patients to which data of eight others treated in our own institution were added. RESULTS: In all but one of these 29 patients the fistula was caused by an atherosclerotic aneurysm, the one exception being caused by an ingested cocktail pin. Gastrointestinal haemorrhage was the predominant symptom, being present in 28 of the patients, while the complete triad of haemorrhage, pain and a pulsating mass was found in only eight patients. Twenty-seven patients were treated with an in situ graft of which 14 are doing well at long term follow-up. CONCLUSIONS: Primary aortoenteric fistula is far more common than one would expect from the number of patients reported in literature. A high index of suspicion based on a complete physical examination remains the key to a correct diagnosis. Direct closure of the intestine and in situ grafting of the aorta is the treatment of first choice. 相似文献
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