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971.
Resource allocation: idealism, realism, pragmatism, openness.   总被引:1,自引:0,他引:1       下载免费PDF全文
Lewis and Charny have come under siege for suggesting remote questioning to decide appropriate medical care. While the criticisms are theoretically valid, the idea is so important practically that Lewis and Charny should be supported and their approach investigated as a way of making medical treatment at least more open and possibly more fair.  相似文献   
972.
The contributors propose a set of newly performed hygienic studies in the widely developed technologies of electrotype, expound a complex of the hazardous occupational factors commonly encountered in modern galvanoplastics, contamination of the equipment, overalls and the skin with the metallic compounds contained in the galvanic electrolytes. Shops with non-isolated electrotype lines were characterized by the most unfavourable labour conditions.  相似文献   
973.
974.
D J Harris  G O Waring  L L Burk 《Ophthalmology》1989,96(11):1597-1607
After penetrating keratoplasty in 52 eyes, keratography refraction and keratometry were used to select appropriate interrupted sutures for removal in order to reduce astigmatism. All eyes had one continuous and either 12 or 16 interrupted nylon sutures. The keratographs were examined retrospectively and separated into six groups on the basis of similar mire patterns. The removal of single sutures associated with three of these patterns reduced astigmatism by the following average amounts: symmetrical oval pattern, 0.44 diopters (D); D-shaped oval pattern, 2.07 D; and focal indentation pattern, 6.60 D. The other three patterns--mildly disrupted mires, incomplete mires, and uninterpretable mires--did not allow quantification of results. Examples of these keratographic patterns are presented and recommendations are made for their use in the management of astigmatism following penetrating keratoplasty.  相似文献   
975.
N-Hydroxythalidomide (1d), a potential metabolite of thalidomide (1a), was synthesized from N-phthalyglutaminic acid anhydride (1b) and O-tetrahydropyraline hydroxylamine, followed by deprotection. The teratogenicity of 1d was studied using the Hen's-Egg-Test model which had been found applicable for 1a. 1d was more teratogenic to chicken embryos compared to 1a. The percentage of teratogenic malformations in the 1d groups was 28-46%, whereas the percentage in the 1a groups was 20-23%. The oxygen protected precursor N-hydroxythalidomide (1c) was less teratogenic (11-15%).  相似文献   
976.
977.
978.
Summary. The quality of the apical seal using the single cone gutta-percha obturation technique with four different dentinal bonding agents was assessed by measuring the linear penetration of methylene blue dye. No leakage was measurable in 75 per cent of the canals sealed with Scotchbond, 70 per cent of canals sealed with Restodent, 60 per cent of canals sealed with Dentin-Adhesit, and in 30 per cent of canals sealed with GLUMA. The mean linear dye penetration in canals sealed with these agents was 0.32, 1.95, 0.57 and 2.41mm, respectively. There was no statistically significant difference between the single cone gutta-percha technique and the laterally condensed gutta-percha technique when Scotchbond was used as sealer ( P > 0.01).  相似文献   
979.
N S Davis 《The Prostate》1987,11(4):353-360
The finding of significant numbers of endocrine-paracrine (EP) cells in the prostate glands of guinea pigs and man suggests that these cells may be important in the regulation or modulation of prostatic function. Serotonin is a biogenic amine common to most prostatic EP cells. In order to extend current knowledge relating to these cells, an assay was developed using high-performance liquid chromatography to quantitate serotonin and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in guinea pig and human prostatic tissue extracts. Levels of serotonin and 5-HIAA in the guinea pig whole-gland preparation were 105.4 +/- 70.6 ng/g and 48.4 +/- 95.7 ng/g, respectively. Normal human prostatic tissue contained 1423.9 +/- 750.8 ng/g serotonin and 66.7 +/- 92.8 ng/g 5-HIAA. Recoveries ranged between 60 and 100%. The detection limits were 24 pg/injection for serotonin and 12 pg/injection for 5-HIAA. This assay provides an expeditious, specific and highly sensitive method for the simultaneous determination of monoamines in guinea pig and human prostatic tissue.  相似文献   
980.
In a series of 75 spines studied at autopsy, the authors found 21 (28%) affected by ankylosing hyperostosis. The 21 cases included three in the cervical spine, 12 in the thoracic spine, and five in the lumbar spine. One case had both thoracic and lumbar spine disease. The average age was 65 years (range, 50-90 years). The mean weight was 85 kg, which was 20 kg more than the mean weight of the nonaffected subjects. Four cases had adult onset diabetes mellitus. No other endocrine or arthritic disease was noted either clinically or at autopsy. No abnormalities of calcium or phosphorus metabolism were found. The cause of death was unrelated to their spine disease, and clinical records were devoid of any major complaints referable to the spine.  相似文献   
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