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H. D. Tagare K. W. Elder D. M. Stoner R. M. Patterson C. L. Nicodemus S. F. Viegas Dr. G. R. Hillman 《Annals of biomedical engineering》1993,21(6):715-726
The carpal regions of ten cadaver extremities were imaged by CT. The images were combined into a 3-dimensional model of the
carpus using a technique based on a dynamic programming algorithm to find an optimal estimate of the location of the bone
boundaries in the CT images. The resulting set of surface points on each bone was used to compute volumes and principal and
antipodal axes for the bones. A spatial coordinate system was established based on the positions of the centroids of three
bones in the distal carpal row. The angular orientations of all carpal bones were determined with respect to this system.
The principal axes for the same bone among ten wrist specimens proved to be more widely dispersed than the antipodal axes
for the same bones. The antipodal axes also correspond more closely to an intuitive notion of the “longest axis” of the bones.
We conclude that the antipodal axis is a more reliable and useful measure of bone orientation than the principal axis. 相似文献
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Preliminary evidence for a role of apolipoprotein E alleles in identifying haemodialysis patients at high vascular risk 总被引:1,自引:0,他引:1
Olmer M; Renucci JE; Planells R; Bouchouareb D; Purgus R 《Nephrology, dialysis, transplantation》1997,12(4):691-693
Conventional risk factors have very low predictive power in identifying
haemodialysis patients at high risk of vascular accidents. A role for
apolipoprotein E isotypes was looked for in a small, but rigorously
defined, cohort of longterm haemodialysis patients. In individuals with
high vascular risk, as identified by higher common carotid intima/media
thickness, we found an excess of apolipoprotein E4 alleles. This
preliminary result requires confirmation in large patient cohorts.
相似文献
5.
Non-operative management of malignant intestinal obstruction 总被引:1,自引:0,他引:1
W H Isbister P Elder L Symons 《Journal of the Royal College of Surgeons of Edinburgh》1990,35(6):369-372
Intestinal obstruction is a relatively common clinical problem in patients with advanced cancer, particularly those with colorectal and ovarian tumours. A proportion of patients have a non-malignant cause for their obstruction, but in the remaining patients obstruction will be caused by advanced malignancy itself. In the past, most patients were either managed surgically or by nasogastric intestinal decompression and intravenous hydration. Surgery in patients with advanced cancer is associated with high mortality and morbidity. Effective surgical decompression is difficult. We have managed 24 patients with advanced abdominal malignancy and previous operative or radiological evidence of intestinal obstruction without operation. The technique is only appropriate for patients in whom a solitary or correctable obstructing lesion can be excluded. The patient is encouraged to take free fluid and a diet low in fibre. Intestinal colic is managed with morphine, the dose required being titrated for each individual patient against background pain and colic. Vomiting is controlled by the parenteral administration of antiemetic drugs. To simplify drug administration, morphine and metoclopramide are mixed in the same syringe and infused subcutaneously simultaneously. In our 24 patients the mean survival rate after the onset of complete obstruction was 29.2 days. The mean dose of morphine infused was 9.2 mg/h, and the mean dose of metoclopramide was 6.9 mg/h. The case of an 82-year-old male patient is presented. We commend the technique to surgeons contemplating surgery in these very difficult patients. It is simple, relatively non-invasive and saves the patients the pain, discomfort and complications of unproductive surgery. 相似文献
6.
Growth and invasion of human melanomas in human skin grafted to immunodeficient mice. 总被引:8,自引:3,他引:5
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I. Juhasz S. M. Albelda D. E. Elder G. F. Murphy K. Adachi D. Herlyn I. T. Valyi-Nagy M. Herlyn 《The American journal of pathology》1993,143(2):528-537
An orthotopic model of human melanoma was developed in which malignant cells were injected into human skin grafted to nude and SCID mice. Melanoma cells proliferated and invaded the human skin grafts with characteristic patterns. Three of six melanomas grew as multiple nodules and infiltered the grafts without major architectural changes in the dermis, whereas the others invaded the dermis along collagen fibers with prominent endothelial vessels. By contrast, melanoma cells inoculated into mouse skin grew as diffusely expanding nodules that did not invade the murine dermis. In human skin grafts, human melanoma cells were angiogenic for human blood vessels, and murine vessels were only found at the periphery of grafts. Tumor cells invaded the human vessels, and four out of seven cell lines metastasized to lungs, suggesting that this model is useful to determine in vivo the interactions between normal and malignant human cells. 相似文献
7.
S R Dager A Khan D Cowley D H Avery J Elder P Roy-Byrne D L Dunner 《Psychopharmacology bulletin》1990,26(3):273-278
Mixed-panic disorder patients (16/60, 27%) randomly assigned to receive blind placebo during a 40-week treatment study were defined as placebo responders based on combined criteria of Hamilton Anxiety Scale score percentage decreases below the median point (-42%), moderate to marked improvement on both clinician and patient Clinical Global Impressions scores, and panic-free at final treatment visit. These criteria applied separately also resulted in a similar clinical grouping and pattern of response. Differential patterns of response between responders and nonresponders occurred across most clinical measures of panic/anxiety. Responders experienced early improvement within the first week of double-blind treatment. This response progressed during treatment and tended to persist during taper and at followup 1 month later. Post-hoc analysis of demographic and clinical features at entrance into the study failed to characterize this stringently defined group of placebo responders. 相似文献
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Mitral balloon valvuloplasty for patients aged over 70 years: an alternative to surgical treatment 总被引:1,自引:0,他引:1
We report the results and one-year follow-up of 20 elderly patients (age range 70-82 years) with severe rheumatic mitral stenosis treated by mitral balloon valvuloplasty (MBV). All 20 were breathless at rest despite treatment with diuretics and digoxin. At cardiac catheterization, successful dilatation was achieved in 17 patients: mean transvalvular mitral gradient fell by 45%, mean cardiac output rose by 24% and mean valve area increased by 76%. There was no procedure-related mortality. At one month, 15 patients had experienced an improvement in symptoms of at least one New York Heart Association class and, at one year, ten had maintained this improvement. Three patients proceeded to mitral valve replacement because of a suboptimal symptomatic result. Mitral balloon valvuloplasty can be successfully performed with significant symptomatic benefit in frail elderly patients unfit for surgery and may also be offered to other selected elderly patients as an alternative to surgical treatment. 相似文献