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901.
Forty-five displaced olecranon fractures including 14 accompanying dislocated radial heads and seven radial head fractures were treated over a 13-year period by the tension band wiring technique. The use of supplemental internal fixation when necessary allows excellent results with the use of this technique, even in the presence of severe comminution or radial head dislocation. Primary silicone radial head implants fractured in all three patients in which they were used, necessitating repeat surgery in two patients to date. While loss of motion in terminal extension was a common aftermath of displaced olecranon fracture (59%), it was usually minor and functionally insignificant. True Kirschner-wire migration was not a common problem and can probably be eliminated by proper technique. The presence of gaps in the intraarticular surface of the semilunar notch of the ulna produced no ill effects and was compatible with excellent results. If only those cases with isolated olecranon fractures in this series are considered, there were good and excellent results in 29 of 30 cases (97%). Excision of the olecranon fragment(s) should be reserved for those cases when anatomic restoration cannot be achieved with internal fixation.  相似文献   
902.
Painful calcinosis appeared at the wrist of an eight-year-old girl with lead poisoning. Careful history revealed that calcification occurred at the site of previous extravasation of calcium disodium edetate (EDTA) used in chelation therapy. Light microscopic, ultrastructural, electron activation, and X-ray diffraction studies demonstrated apatites with some suggestion of an admixture of octacalcium phosphate.  相似文献   
903.
904.
Forearm bone mineral density was measured in 557 postmenopausal women from whom a history of fractures was also obtained. Known cases of osteoporosis were excluded. The mean age of the subjects was 59 years. Ninety-eight of the subjects had sustained a fracture since the menopause and 37 had done so before the menopause. There had been 188 fractures in all. The mean bone density was significantly lower in the subjects who had experienced a fracture than in those who had not experienced a fracture; this was also true of subjects who had suffered a fracture before the menopause. The lowest bone densities were observed in subjects who had suffered forearm fractures, followed by those who had suffered fractures of the rib, ankle and foot. The mean bone density in subjects with more than one fracture was significantly lower than in those with only one fracture. The difference in bone density between subjects with and without a history of fractures was most significant in the younger subjects and became progressively less significant with age. The estimated relative fracture risk was 3.1 in the group with the lowest bone densities and zero in the group with the highest bone densities.  相似文献   
905.
906.
Assessing the role of family planning in reducing maternal mortality   总被引:1,自引:0,他引:1  
It is widely believed that family planning has important benefits for both maternal and child health. Despite this, little work has been done to quantify the potential effect of family planning in reducing maternal mortality. This paper assesses the impact of family planning in averting maternal deaths, and discusses the overall ability of risk strategies to address the bulk of maternal mortality. The practical difficulties of providing effective contraception to populations with high maternal mortality are addressed, and the need for maternal health care services as an adjunct to useful family planning programs is emphasized. Although family planning cannot by itself cause a substantial reduction in risk of pregnancy, the combined strategies of general fertility reduction, abortion services, and family planning for high-risk groups might effectively address about half of all maternal mortality in the developing world. Pregnancy and delivery care have the potential for saving large numbers of lives with appropriate interventions. It is concluded that reproductive risks can be reduced only by preventing unwanted pregnancies and protecting maternal health during wanted ones.  相似文献   
907.
Plasma pyridoxal-5'-phosphate and pyridoxal levels increased significantly (p less than 0.05) when single, oral bolus doses of pyridoxine were increased from 10 to 25 and from 25 to 50 mg in nine female volunteers. However, when the dose was increased to 100 mg, plasma pyridoxal-5'-phosphate levels did not differ significantly from those recorded after the 50 mg dose. Within 3 h plasma pyridoxal levels rose with a factor of 3.85 compared with the 50 mg dose but high pyridoxal levels were eliminated from the circulation. Renal clearance of pyridoxal remained a constant, low percentage (less than 2.0%) of each pyridoxine supplement in spite of the observed very high circulating pyridoxal levels. Pyridoxine supplementation is discussed in relation to circulating pyridoxal-5'-phosphate and pyridoxal availability for cellular metabolism.  相似文献   
908.
We have compared the effects of acetyl salicylic acid (ASA, aspirin) and choline magnesium trisalicylate (CMT), a non-acetylated salicylate product, on platelet aggregation in human whole blood ex-vivo. Using a whole blood platelet counter, platelet aggregation was quantified by measuring the fall in the number of single platelets at peak aggregation in response to collagen, arachidonic acid (AA), as well as spontaneous aggregation. In double blind and random order, 12 healthy volunteers received, on two separate occasions 10 days apart, a single oral dose of 652 mg ASA or 655 mg CMT. Despite a comparable absorption of salicylic acid from the two drugs, ingestion of ASA resulted in a marked inhibition of platelet aggregation induced by collagen (p less than 0.005), AA (p less than 0.01) and spontaneous aggregation (p less than 0.01), whereas such effects were not observed after CMT ingestion. We suggest that CMT may have therapeutic potential as an alternative to aspirin when inhibition of platelet aggregation can induce bleeding complications.  相似文献   
909.
A method, based on bedside determinations of blood glucose by nursing staff, was designed to control the administration of insulin to diabetic patients during and following open heart surgery. A computer-controlled intravenous infusion pump was used to deliver the insulin. Excellent control of the hyperglycaemia normally associated with open heart surgery was achieved, with 84 percent of measured blood glucose values falling within 2 mmol/litre of the target value of 6 mmol/litre. The method proved to be simple, effective, and safe.  相似文献   
910.
R B Raynor 《Neurosurgery》1986,19(1):108-110
A patient with Charcot's disease of the lumbar spine presented with weakness of one extremity. Myelographic and x-ray film studies indicated stenosis and compression due to degenerative changes. Although decompression and fusion were considered, computed tomographic scans indicated the wide extent and location of the destructive changes. Nonoperative treatment was elected because of the high risk of fusion failure and instability.  相似文献   
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