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991.
992.
L A Palinkas 《Aviation, space, and environmental medicine》1987,58(11):1062-1065
A longitudinal perspective was employed to test the hypothesis that there is an increased risk of hospitalization among Antarctic winter-over personnel during the first year subsequent to this duty. Subjects were 327 enlisted Navy men who wintered-over between 1963 and 1974 and a control group of 2,396 enlisted men who volunteered and were accepted for winter-over duty but who did not winter-over. A 15-year period from 1965 to 1979 was established for follow-up. Follow-up of subjects subsequent to screening for Operation Deep Freeze was conducted in 6-month intervals for the first 4 years. Results indicated that the total rates of first hospitalization during the 6 months prior to Antarctic duty and the first 6 months in Antarctica among winter-over personnel were significantly lower than the rates for the control group. No significant difference in the rates of the two groups was observed for the 12 months subsequent to winter-over duty. 相似文献
993.
Sutureless bowel anastomosis using Nd:YAG laser 总被引:5,自引:0,他引:5
Small bowel anastomoses were performed without sutures by using the Nd:YAG laser to produce welded enterotomies. Optimal energy levels for contact and noncontact laser were determined. Anastomoses produced using five target energy levels between 100 and 500 J were examined. Short-term anastomotic strength of these enterotomies was measured 1 min after the welding. Bursting pressure of the laser welded enterotomies was compared to the bursting pressure of traditional two-layer, inverting, interrupted sutured bowel anastomoses. The overall mean bursting pressure of non-contact-welded enterotomies was 50.6 mmHg. Optimal laser settings determined in this initial phase were then used to produce anastomoses in rabbits which are recovered postoperatively for 1 or 2 weeks in order to examine long-term viability and integrity of the anastomoses. All chronic rabbit preparations recovered without complication. The mean bursting pressure was 200 mmHg, not significantly different from that of uncut bowel or two-layer sutured anastomosis. 相似文献
994.
Surgical treatment of displaced olecranon fractures by tension band wiring technique 总被引:2,自引:0,他引:2
G Wolfgang F Burke D Bush J Parenti J Perry B LaFollette S Lillmars 《Clinical orthopaedics and related research》1987,(224):192-204
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
995.
H R Schumacher A L Osterman S J Choi P B Weisz 《Clinical orthopaedics and related research》1987,(219):221-225
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
996.
997.
998.
Deep-frozen cancellous allografts have been used to restore the proximal femur of 23 hips following failed total hip arthroplasty. The canal is cleared and reaming is performed under direct vision through a cortical window. A modified Huckstep prosthesis permits early weight-bearing on the distal femur regardless of the state of proximal bone, but retains the option for later restoration of proximal loading once grafts appear mature. This transfer has been performed on four occasions. All 23 patients have had relief of pain with early ambulation. The follow-up periods ranged from six to 30 months. With the exception of one deep infection, the grafts have not undergone resorption in this period of follow-up study. Consolidation appears slower when the defect has followed multiple operations than following an initial revision for prosthetic loosening. The basic bone bank facilities are required for the supply of frozen allografts. 相似文献
999.
1000.
The extracellular matrix of stratum corneum: role of lipids in normal and pathological function 总被引:4,自引:0,他引:4
The mammalian stratum corneum, formerly treated as a homogeneous film, is now more properly viewed as a two-compartment system. The cornified cell is protein-enriched and lipid-depleted, lying embedded in an expanded extracellular matrix of highly nonpolar lipids. Because of its strategic location between the cornified layer, this lipid matrix is responsible for many phenomena related to the permeability barrier, as well as cohesion and desquamation. Thus, manipulation of this compartment could lead to enhanced drug delivery and improved lubrication, as well. 相似文献