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71.
Paramagnetic macrocyclic chelates show promise as magnetic resonance (MR) imaging contrast agents due to stability and relaxivity comparable to those of DTPA-type chelates. For the three copper and manganese macrocyclic complexes studied in aqueous solution, T1 and T2 relaxivities ranged from 0.14 to 5.88 mM-1sec-1 at 6.25 MHz. In rats, the intravenous administration of 16 mumol/kg of Mn(cyclam) caused the liver T1 relaxation rate to double at 15 minutes after injection. T1 measurements by pulsed MR imaging and manganese analyses on excised tissue showed that both relaxation rate (1/T1) and manganese content of liver and kidney increase linearly with the dosage of Mn(cyclam). The linear relationship between 1/T1 and manganese content can be considered an "in tissue" relaxivity plot for the agent. The resulting relaxivity is 54 mM-1sec-1 in liver, compared with 3.1 mM-1sec-1 in aqueous solution. Although this work is preliminary, the implication for medical MR imaging applications is that macrocyclic contrast agents can be effective at approximately one-tenth the current typical dose used for gadolinium DTPA. 相似文献
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Evaluation of the Sydney "Quit. For Life" anti-smoking campaign. Part 1. Achievement of intermediate goals 总被引:5,自引:0,他引:5
J P Pierce T Dwyer G Frape S Chapman A Chamberlain N Burke 《The Medical journal of Australia》1986,144(7):341-344
The "Quit. For Life" campaign was a media-based programme that was aimed at reducing the prevalence of smoking in Sydney. The programme committee set four intermediate goals which it felt had to be met for such a change in prevalence to occur. From households selected at random in Sydney and Melbourne, 5713 people were interviewed to assess whether the campaign attained these goals. The television commercials that were designed for the campaign, their frequency and the timing of their screening produced a higher recall of the commercial's message and the use of campaign back-up services than were specified originally in the goals. During the campaign there was a progressive increase in the number of smokers in Sydney who reported that they were likely to quit; this was significantly different from Melbourne data by the end of the campaign and thus fulfilled another campaign goal. However, shortly after the campaign ended, the proportion of smokers who intended to quit smoking was the same in the two cities. A cohort study of 949 people from the baseline study showed that, during the 12-month period of follow-up, 66% of Sydney smokers tried to stop or to reduce their smoking. In the control city, Melbourne, 60% of smokers reported making such attempts. Of the original smokers, 23% in Sydney and 9% in Melbourne quit during the follow-up period--a statistically significant difference. As well, 10% of the original ex-smokers in Sydney and 11% in Melbourne relapsed, while 4% of nonsmokers in both cities began smoking by the end of the second survey. 相似文献
74.
The failure of physician education as a cost containment strategy. Report of a prospective controlled trial at a university hospital 总被引:9,自引:1,他引:8
S A Schroeder L P Myers S J McPhee J A Showstack D W Simborg S A Chapman J K Leong 《JAMA》1984,252(2):225-230
To test the hypothesis that physician education is an effective strategy to reduce total hospital costs, we evaluated three educational interventions at a large university hospital. This prospective controlled study spanned two academic years and involved 1,663 patients and 226 house staff. In the first year, weekly lectures on cost containment (medicine and surgery) and audit with feedback (medicine only) both failed to produce a significant change in total hospital charges. The "dose" of the intervention was increased on medicine in the second year by combining the lecture and audit strategies. Again, total charges did not change significantly. While decreased use occurred for certain selected services, the impact was not great enough to affect total hospital charges significantly. We conclude that, in the absence of other cost containing incentives, physician education alone is not an effective hospital cost containment strategy. 相似文献
75.
James M. Chapman Jr. Steven D. Wyrick James H. Maguire George H. Cocolas Iris H. Hall 《Pharmaceutical research》1984,1(6):267-269
A number of substituted phthalimide, 1, 8-naphthalimide, succinimide and glutarimide derivatives demonstrated significant hypolipidemic activity at 20 mg/kg/ day, I.P. after 16 days dosing. The N-(n-pentyl) succinimide proved to be the most potent analogue of the new compounds, lowering serum triglyceride levels 51 % and serum cholesterol 47 % after 16 days dosing in mice. For the N-substituted derivatives, i. e., n-butyl, butanone, and propionic acid, of these four cyclic imides, there appeared to be no obvious trend in ability to reduce serum lipid levels. In general, the 1,8-naphthalimide and glutarimide derivatives appeared to be less active than phthalimide and succinimide. However, the -phenylsuccinimide afforded less activity than the -phenylglutarimide. Most of the derivatives at 20mg/kg/day demonstrated improved activity over clofibrate at 150mg/kg/day. 相似文献
76.
Protein supplements are increasingly used by older people to maintain nutrition and prevent or treat loss of muscle function. Daily protein requirements in older people are in the range of 1.2 gm/kg/day or higher. Many older adults do not consume this much protein and are likely to benefit from higher consumption. Protein supplements are probably best taken twice daily, if possible soon after exercise, in doses that achieve protein intakes of 30 gm or more per episode. It is probably not important to give these supplements between meals, as we have shown no suppressive effects of 30 gm whey drinks, and little if any suppression of 70 gm given to older subjects at varying time intervals from meals. Many gastrointestinal mechanisms controlling food intake change with age, but their contributions to changes in responses to protein are not yet well understood. There may be benefits in giving the supplement with rather than between meals, to achieve protein intakes above the effective anabolic threshold with lower supplement doses, and have favourable effects on food-induced blood glucose increases in older people with, or at risk of developing, type 2 diabetes mellitus; combined protein and glucose drinks lower blood glucose compared with glucose alone in older people. 相似文献
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79.
Summary Based upon findings from 60 cadavers (120 sides), the incidence of superior laryngeal nerve loop, connecting the cervical sympathetic chain and the superior laryngeal nerve and its branches, the external and internal laryngeal nerve, was 98.3% (118 out of 120 sides). In most cases the loop connected the sympathetic chain and the external laryngeal nerve. The external laryngeal nerve was looped, and not linear as traditionally thought. The loop could be divided into three categories, V-shaped, U-shaped and mixed, and subdivided into 5 types and 17 subtypes according to morphological variation. The loop without exception innervated not only the cricothyroid muscle, but also the thyroid gland. The loop is one of the origins of the thyroid nerve. It seems that for thyroid surgery the loop, when lower in position, should be carefully separated from the superior thyroid vessels before the latter are ligated, in order to preserve a normal nerve supply to the muscle as well as to the part of the gland that remains after surgery.
L'anse du nerf larynge supérieur, étude anatomique et applications chirurgicales
Résumé La fréquence d'une anse du nerf laryngé supérieur réalisant une anastomose entre la chaine sympathique cervicale et le nerf laryngé supérieur et/ou ses branches (rameau laryngé externe et ingerne), est de 98,3 % (118/120). Ce résultat s'appuie sur l'étude de 60 cadavres. Dans la plupart des cas, l'anastomose se fait entre la chaine sympathique cervicale et le rameau laryngé externe. Ce rameau laryngé externe a un trajet curviligne et non linéaire conformément aux données classiques. Il existe trois catégories d'anses : en "V", en "U" et mixte ; on peut également les subdiviser en 5 types et 17 sous-types en fonction des variations morphologiques. Cette anse innerve constamment non seulement le muscle cricothyroïdien mais aussi la glande thyroïde dont elle fournit une partie de l'innervation. Lors de la chirurgie thyroïdienne, si l'anse est en position basse, les nerfs doivent être soigneusement disséqués et séparés des vaisseaux thyroïdiens supérieurs avant ligature de ces derniers de façon à conserver l'innervation normale du muscle et de la partie restante de la glande.相似文献
80.
Epicoccum allergy: skin reaction patterns and spore/mycelium disparities recognized by IgG and IgE ELISA inhibition 总被引:1,自引:0,他引:1
Comparable degrees of skin reactivity were observed towards spore and mycelium extracts from two isolates of Epicoccum and to one preparation of Alternaria in 35 rural and 120 university patients. The best experimental extracts detected Epicoccum sensitivity in 70% of the group tested while the commercial extract detected sensitivity in only 6%. Skin reaction correlations were greatest within isolates (eg, spore-A/mycelium-A), then for specific fungus parts (eg, spore-A/spore-B), then between isolates and parts (spore-A/mycelium-B). High correlations were found between individual IgG and IgE ELISA values for all antigens using serum from Epicoccum skin-reactive patients. ELISA inhibition results suggested that significant cross-reactivity exists between Epicoccum and Alternaria antigens recognized by IgG but not by IgE. ELISA inhibition cross-reaction patterns among Epicoccum antigens were comparable to skin reactions while IgG patterns showed little variability. Further characterization of spore/mycelium and interstrain recognition patterns among different immunoglobulin isotypes will be necessary before complete standardization of extracts from different parts of fungi will be possible. The use of spore material for skin testing and treatment of Epicoccum sensitivity appears to be both premature and unnecessary at this time. 相似文献