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81.
82.
Summary The load axis of the curved proximal femur lies not inside but outside the bone. Therefore, high bending forces are acting, the medial cortex absorbing pressure and the lateral cortex absorbs tension. In a transverse fracture, a laterally applied plate will absorb the tensile stresses and the medial cortex, the pressure forces. When the medial buttress due to a bony defect is missing, the laterally applied plate is subjected to cyclic bending and will undergo fatigue fracture. This dilemma is compensated by a wave plate with bone graft: the compression forces are redirected to the lateral cortex, and the plate is again subjected to tension. Furthermore, since the plate stands away from the bone, it does not disturb the blood supply at the fracture site and thus bone healing. 相似文献
83.
R S Weber P Gidley W H Morrison L J Peters P Hankins P Wolf O Guillamondegui 《American journal of surgery》1990,160(4):415-419
Between 1974 and 1984, 173 patients were treated for squamous cell carcinoma of the tongue base. Fifty-four patients had T1 or T2 primaries, while 115 patients had T3 or T4 tumors (4 were not staged). Lymph node metastasis was present in 120 patients. Early primary tumors treated with surgery or radiotherapy had a control rate of 83% (5 of 6 tumors) and 89% (40 of 45 tumors), respectively. For advanced primary tumors, definitive radiotherapy produced a local control rate of 55% (42 of 76 tumors), compared with 79% (23 of 29 tumors) for surgery and postoperative radiotherapy. If primary control was obtained, the regional failure rate was less than 10%. Tumor growth patterns were predictive of the response to radiotherapy. The primary control rate at 2 years for 21 patients with exophytic tumors was 84% as opposed to 58% for 62 patients with ulcerative-infiltrative tumors (p = 0.04). Radiotherapy is effective for early stage or exophytic tumors, whereas for advanced or deeply invasive tumors combined therapy enhances local control. 相似文献
84.
R Mokni A Chakar F Bleiberg-Daniel JL Mahu PA Walravens P Chappuis J Navarro D Lemonnier 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(6-7):539-543
Biochemical markers of nutritional status (albumin, transthyretin, insulin-like growth factor-I and zinc) were measured in slowly growing two- to five-year-old, low-income Parisian children whose weight-for-height or height-for-age z scores (WHZ or HAZ) were between — 1 and — 2 SD of the NCHS median. The results were compared to controls who were matched for age, sex, and ethnic origin with WHZ and HAZ between — 1 and + 2 SD. Mean serum levels of transthyretin, albumin and insulin-like growth factor-I and mean plasma zinc concentrations were significantly lower in the growth-impaired children than in the controls ( p = 0.002, p = 0.006, p = 0.015, and p = 0.035, respectively). While the height-retarded children had low mean serum insulin-like growth factor-I values, the weight-retarded subjects had decreased levels of albumin, transthyretin and zinc when compared to controls. Lower mean levels of nutritional markers in healthy, slowly growing children suggest that inadequate dietary intakes of zinc, protein and/or energy may result in marginal delays in weight and height gains. 相似文献
85.
T A Karnezis M B Murphy R R Weber K S Nelson B J Tripathi R C Tripathi 《Experimental eye research》1988,47(5):689-697
The lack of specific agonists and antagonists has, until recently, precluded investigation of a role for dopamine receptors in the control of intraocular pressure. In the present study, we have examined the effects of fenoldopam, a novel selective dopamine1 (DA1) receptor agonist, on intraocular pressure, in eight healthy human volunteers. Fenoldopam, infused intravenously at 0.5 micrograms kg-1 min-1, increased intraocular pressure from 14.6 +/- 0.9 to 17.6 +/- 1.4 mmHg (P less than 0.05) while a control saline infusion had no effect. Pupil diameter and blood pressure did not change. In the same subjects, i.v. norepinephrine or angiotensin II both increased intraocular pressure--from 13.8 +/- 1.4- to 17.6 +/- 1.4 mmHg and from 13.4 +/- 1.3- to 17.5 +/- 1.7 mmHg respectively (P less than 0.05), and mean arterial pressure by about 20 mmHg. These data suggest that: (1) DA1 receptor activation can modulate intraocular pressure; (2) the intraocular pressure effects of the DA1 receptor agonist, fenoldopam, are independent of changes in systemic blood pressure, in contrast to those of norepinephrine or angiotensin II where intraocular and systemic blood pressures increase in parallel; (3) the ability of a DA1 receptor antagonist to lower intraocular pressure merits investigation. 相似文献
86.
Joseph C. Gretzula D.O. Osmar Hevia B.S. Lawrence S. Shachner M.D. John H. DiLiberti M.D. † R. H. A. Ruvalcaba M.D. ‡ James R. Schimshock M.D. § Richard G. Weleber M.D. Fahed Halal M.D. # Mark H. Lipson M.D. Bruce Blumberg M.D. †† Paul J. Weber M.D. 《Pediatric dermatology》1988,5(1):28-32
In 1980 a syndrome was first described in two adult males, consisting of macrocephaly, pigmented macules on the glans and shaft of the penis, and hamartomatous intestinal polyps. Since then, 10 additional cases have been identified. Herein, we present two new cases and review the cutaneous manifestations as well as additional features in patients with the Ruvalcaba-Myhre-Smith syndrome. 相似文献
87.
JI Elizalde ; J Clemente ; JL Marin ; J Panes ; B Aragon ; A Mas ; JM Pique ; J Teres 《Transfusion》1997,37(6):573-576
BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk. 相似文献
88.
Bacterio-expert is a simple expert system for assisting in the validation of antibiotic sensitivity testing. This system is incorporated in a data acquisition and editing program for bacteriologic test (Bacterio program written in Turbo-Pascal for personal computer users by the same authors). The principles of this system are explained and results with 4,053 antibiotic sensitivity tests on Staphylococcus aureus isolates are reported. Approximately 10% of tests required corrections. 相似文献
89.
R. W. Watts I. A. Fletcher G. K. Kiroff C. Weber H. Owen J. L. Plummer 《ANZ journal of surgery》1995,65(8):588-591
This study investigated the feasibility of using patient-controlled analgesia (PCA) effectively in a small 70 bed isolated rural hospital. The tirst 50 patients to use a Bard PCA 1, in the Port Lincoln Hospital, South Australia, were studied. The patients consumed morphine at a mean rate of 1.24 mg/h and used PCA for a mean of 48 h. Thirty-eight per cent of patients required treatment for nausea and other complications which is similar to the rate of those in other published series. Visual analogue pain scores showed excellent pain control, generally without evidence of oversedation; however, there was one episode of respiratory depression. Seventy-eight per cent of patients reported that their pain was relieved most or all of the time. The study demonstrated that a PCA service provided by nursing staff, the GP anaesthetist and rural surgeons is feasible in an isolated rural hospital. 相似文献
90.
Grundmann R. Weber F. Pichlmaier H. 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1987,372(1):861-862
Zusammenfassung Über 52 Monate wurden 4747 allgemeinchirurgische Planeingriffe prospektiv erfasst. Postoperative Komplikationen (Wundinfektion, Pneumonie, Revision, Letalität) wurden mit einem Punktescore bewertet, der die konkrete Zahl der zu erwartenden Komplikationen auf 10 Operationen der gleichen Art wiedergibt. Der Wert einer solchen Erfassung des Komplikationsrisikos zeigte sich in Verlaufsuntersuchungen, bei denen die postoperativen Komplikationen im 4-Monatsrhythmus aufgetragen wurden: Ursachen von Komplikationen konnten erforscht und beseitigt werden. 相似文献