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51.
We report the clinical and operative details of seven cases of fracture of the femoral stem of the Ring TiMESH cementless hip prosthesis (two were cemented and five uncemented). Six fractures occurred in the proximal one-third of the stem and one at mid-stem. The failures are attributed mainly to two defects in stem design, the narrowness of the anteroposterior dimensions and the depth of the recess for the titanium mesh pads. Great difficulty was experienced in removing the osseo-integrated distal fragments of the broken stems.  相似文献   
52.
A 4-year, 9-month-old boy had a history of leukocoria of the right eye for approximately six months prior to admission. The other eye was normal. There was no family history of retinoblastoma. Funduscopy disclosed a large white mass extending from the nasal pars plana to the mid-pupillary zone and the posterior pole with a near total retinal detachment in the superior temporal quadrant. A B-scan ultrasound showed an echo dense area of the anterior portion of the mass. A CT scan showed intraocular tissue densities with no evidence of optic nerve involvement or extraocular extension. Immunohistochemistry of a fresh frozen portion of tumor revealed reactivity with antibodies directed against interphotoreceptor retinoid-binding-protein (IRBP), neuron-specific enolase, glial fibrillary acidic protein, S-antigen, focal reactivity with opsin, and scattered cytoplasmic staining for cyclic GMP and cyclic GMP phosphodiesterase. Biochemical analysis of fresh frozen tissue samples confirmed the presence of IRBP. Transmission electron microscopy disclosed occasional Flexner-Wintersteiner rosettes connected by zonula adherens-like junctions. These showed inner segment-like structures containing prominent mitochondria, portions of cilia and fragments of outer segment material. These data, along with the immunocytochemistry indicates a predominant neuronal nature of the tumor cells with significant photoreceptor-like differentiation.  相似文献   
53.
The possibility that injection-molded intraocular lenses (IOLs) with imperfections called iridescent clefts could have a decreased threshold to neodymium: YAG (Nd:YAG) laser-induced damage was investigated. Thresholds for Nd:YAG laser-induced damage were determined for injection-molded and lathe-cut polymethylmethacrylate lenses. When aimed at a membrane in contact with a posterior convex surface, the average thresholds were 0.96 +/- 0.18 mJ (Standard deviation [SD]) and 1.80 +/- 0.55 mJ, respectively. The difference was significant at P = 0.001. When injection-molding polymethylmethacrylate was used to make lathe-cut IOLs, very few iridescent clefts were present, and the threshold to Nd:YAG laser-induced damage was 0.94 +/- 0.25 mJ. Iridescent clefts are therefore produced during the injection-molding process but they do not lower the threshold to Nd:YAG laser-induced damage. Rather, the reduced threshold in injection-molded lenses is most probably a result of the polymethylmethacrylate used in their manufacture. Clinically, iridescent clefts in a lens suggest that it has been manufactured by an injection-molding process and that Nd:YAG laser posterior capsulotomy must be performed at the lowest possible energy level to avoid damage.  相似文献   
54.
55.
A well-nourished alcoholic patient developed a subacute myopathy which responded rapidly to correction of severe hypomagnesaemia. The finding of profound hypocalcaemia prompted the measurement of serum magnesium. Magnesium deficiency should be looked for in any alcoholic patient with a myopathy as the prognosis seems better than in many other forms of alcoholic myopathy. Correction of the magnesium deficiency corrects the hypocalcaemia without the need for calcium supplementation.  相似文献   
56.
57.
Why is there a left side underestimation in rod bisection?   总被引:4,自引:0,他引:4  
Subjects set the extremities of a horizontal rod to appear equidistant from a central reference point, with or without central fixation. On either side, the contrast (salience) of the rod against the background was high or low. Extents to the left were set smaller than those to the right, an effect (LSU) which was stronger with central fixation, indicating that both hemispatial and anatomical pathway factors contribute. Reduced salience on the left increased rather than decreased the LSU, indicating the importance of attentional factors.  相似文献   
58.
Volume and outcome of coronary artery bypass graft surgery   总被引:1,自引:1,他引:0  
J M Wilson  P Menkhaus  B W Gustin 《JAMA》1987,257(18):2434-2435
  相似文献   
59.
M Ma  H Hu  F Kutlar  J B Wilson  T H Huisman 《Hemoglobin》1987,11(5):473-479
A slow-moving gamma chain variant was discovered in the cord blood of an infant born to parents of the Han nationality from Jiangsu. The variant, which migrated electrophoretically at alkaline pH between Hb A and Hb D, was characterized by an Asp----His substitution at gamma 73, while residues gamma 75 and gamma 136 were occupied by Ile and Ala, respectively. As the A gamma T-chain was also present, this baby has two types of abnormal gamma-chain. The variant was named Hb F-Xin-Su.  相似文献   
60.
Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined.  相似文献   
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