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101.
Relationship between Hip Extension Range of Motion and Postural Alignment   总被引:1,自引:0,他引:1  
The purpose of this study was to examine the relationships between hip extension range of motion (ROM) and three determinants of postural alignment: standing pelvic tilt, standing lumbar lordosis, and abdominal muscle performance. The subjects were 25 healthy adults ranging in age from 21 to 49 years. The Pearson product-moment correlation of hip extension ROM with pelvic tilt was -0.04, with lumbar lordosis -0.09, and with abdominal muscle performance 0.09. These results indicate that these variables are not related. This study demonstrates that the hypothetical correlation among these clinical parameters needs to be reassessed. J Orthop Sports Phys Ther 1990;12(6):243-247.  相似文献   
102.
103.
The goal of these studies was to develop a suramin dosing schedule that would maintain suramin plasma concentrations in mice in the 150-250 mu g/ml range. A high pressure liquid chromatography method was used to determine suramin plasma concentrations in mice. For pharmacokinetic studies CD2F(1) mice were treated intraperitoneally with 140 mg/kg of suramin. These pharmacokinetic data were used to develop a clinically relevant dosing regimen. To test the efficacy of this dosing regimen, athymic nude mice were implanted orthotopically with PC-3 prostate carcinoma cells, randomized, and treated intraperitoneally. The pharmacokinetically derived dosing regimen resulted in no antitumor effect against PC-3 prostate tumors. Suramin plasma concentrations ranged from 155 to 258 mu g/ml over the 14-day therapy period with tumor concentrations in the 53-241 mu g/g wet weight range.  相似文献   
104.
The prognosis of patients who bleed from esophageal varices is dismal. Prophylactic treatment of the varix or the elevated portal venous pressure offers a possibility of improving the outlook for these patients. However, as only approximately one-third of patients with varices bleed during their lifetime, correct identification of high-risk patients is vital before embarking on prophylaxis. At present, neither European or Japanese selection criteria are perfect in this respect. The documented incidence of initial variceal bleeding varies between 27% and 48%, and most bleeding episodes occur within the first year after varices are diagnosed. Data from six randomized controlled trials comparing prophylactic -blockers with placebo demonstrated a decreased incidence of bleeding in propranolol-treated patients, which in large measure may depend on patient compliance and did not significantly affect survival in all but one study. Early randomized studies of prophylactic sclerotherapy have shown significant reductions in both the incidence of bleeding and mortality, but this promise has not been sustained by subsequent trials, and indeed sclerotherapy was detrimental in two studies. The impressive results in highly selected patients treated in Japan by prophylactic surgery are unlikely to be repeated in a Western setting, involving patient populations that consist predominantly of alcoholic cirrhotics. At present prophylaxis with -blockade seems to offer the best therapeutic option, but the future may lie in the development of new interventional techniques such as tranjugular intrahepatic portosystemic stent shunting (TIPS) or variceal banding, and ultimately with hepatic transplantation.
Resumen El pronóstico de los pacientes que sangran como consecuencia de várices esofágicas es sombró. El tratamiento profiláctico de las várices o de la elevada presión portal ofrece una posibilidad de mejorar el futuro de estos pacientes.Sin embargo, como apenas aproximadamente un tercio de los pacientes con várices sangran en el curso de su vida, la correcta identificación de los casos de alto riesgo es de vital importancia antes de embarcarse en tratamiento profiláctico.En la actualidad ni los criterios de selección europeos ni los japoneses pueden considerarse como perfectos a este respecto. La frecuencia del sangrado varicoso inicial oscila entre 27% y 48%, y la mayoría de los episodios hemorrágicos ocurren dentro del primer año después de establecido el diagnóstico de las várices. Los resultados de seis (6) ensayos clinicos randomizados en que compararon los beta-bloqueadores con placebeo demuestran una disminución en la incidencia de sangrado en los pacientes tratados con propranolol, lo cual en gran parte depende de la obediencia del paciente, pero afectó en forma significativa la sobrevida, excepto en uno de los estudios.Anteriores estudios randomizados sobre escleroterapia profiláctica han demostrado reducciones significativas tanto en la incidencia de sangrado como en la mortalidad, pero ésto no ha sido reproducido en ensayos clínicos subsiguientes, y en realidad la escleroterapia pareció ser nociva en dos estudios. Los impresionantes resultados en pacientes altamente seleccionados logrados en el Japón con la cirugía profiláctica muy probablemente no lograrán ser reproducidos en Occidente, donde las poblaciones de pacientes están conformadas predominantemente por cirróticos alcohólicos. En el momento actual la profilaxis con beta-bloqueadores parece ser la mejor opción terapéutica, pero el futuro puede bien ser el desarrollo de nuevas técnicas intervencionistas tales como shunts transyugulares intrahepáticos (TIPS) o la ligadura endoscópica de las várices y, por último, el trasplante de hígado.

Résumé Le pronostic des patients ayant saigné de varices oesophagiennes est médiocre. Le traitement prophylactique des varices ou d'une hypertension portale permet une amélioration potentielle du pronostic de ces patients. Cependant, comme seulement un tiers des patients avec des varices saignent pendant leur vie, l'identification correcte des patients à risque élevé est capitale avant d'envisager une politique prophylactique généralisée. Actuellement, ni les critères européens ni les critères japonais ne sont suffisants pour déterminer cette population à risque. L'incidence d'hémorragie par rupture des varices initiale va de 27% à 48% dans la littérature et la plupart des hémorragies se produisent pendant la première année après le diagnostic de varices oesophagiennes. Les résultats provenant de six études comparant les béta bloqueurs à un placebo ont démontré une baisse de l'incidence de l'hémorragie chez les patients traités par le propranol. Ce résultat peut certes être attribué à une différence de coopération parmi les patients: la survie n'est pas différente d'une étude à l'autre sauf une. Les études randomisées de sclérothérapie prophylactique ont démontré une réduction significative dans l'incidence d'hémorragie et de la mortalité, mais cet espoir n'a pas été retrouvé par les essais suivants et la sclérothérapie a été néfaste dans deux de ces essais. Il est peu probable que les résultats impressionnants recueillis au Japon puissent être reproduits en Occident où la population est composée en grand majorité par des cirrhotiques d'origine alcoolique. Actuellement, la prophylaxie par béta-bloqueurs semble être le meilleur des traitements mais à l'avenir, la meilleure option thérapeutique pourrait être le shunt intrahépatique transjugulaire ou le wrapping périoesophagien et ultérieurement la transplantation hépatique.
  相似文献   
105.
106.
A modern malaise   总被引:1,自引:0,他引:1  
JS Robertson Dr   《Public health》1999,113(4):155-156
  相似文献   
107.
108.
Objectives . The purpose of this study was to determine whether significant dental abnormalities are likely to be overlooked in the anterior region of the maxilla if, in the absence of any clinical indication for further views, the only radiograph used during an initial orthodontic assessment is a good-quality orthopantomogram (OPT).
Sample and methods . Two orthodontists examined, retrospectively, the written and radiographic dental hospital records of 1169 consecutive, new, young patients who on their first visit to a dental teaching hospital underwent radiographic examination comprising an OPT and one or more supplementary radiographs of the anterior maxilla.
Results . In five cases (0·43%) significant findings would have been overlooked if the intra-oral views had not been taken. These included periapical lesions and supernumerary teeth, but in three of the cases the image quality of the OPT was poor.
Conclusions . If the OPT is not routinely supplemented by intra-oral views, the chances of completely missing significant findings in the anterior maxilla are small, provided a thorough history and clinical examination have been completed and the image quality of the OPT is good.  相似文献   
109.
110.
BACKGROUND: The purpose of this study was to compare the biomechanical efficacy of an injectable calcium-phosphate bone cement (Skeletal Repair System [SRS]) with that of Kirschner wires for the fixation of intraarticular fractures of the distal part of the radius. METHODS: Colles fractures (AO pattern, C2.1) were produced in ten pairs of fresh-frozen human cadaveric radii. One radius from each pair was randomly chosen for stabilization with SRS bone cement. These ten radii were treated with open incision, impaction of loose cancellous bone with use of a Freer elevator, and placement of the SRS bone cement by injection. In the ten control specimens, the fracture was stabilized with use of two horizontal and two oblique Kirschner wires. The specimens were cyclically loaded to a peak load of 200 newtons for 2000 cycles to evaluate the amount of settling, or radial shortening, under conditions simulating postoperative loading with the limb in a cast. Each specimen then was loaded to failure to determine its ultimate strength. RESULTS: The amount of radial shortening was highly variable among the specimens, but it was consistently higher in the Kirschner-wire constructs than in the bone fixed with SRS bone cement within each pair of radii. The range of shortening for all twenty specimens was 0.18 to 4.51 millimeters. The average amount of shortening in the SRS constructs was 50 percent of that in the Kirschner-wire constructs (0.51+/-0.34 compared with 1.01+/-1.23 millimeters; p = 0.015). With the numbers available, no significant difference in ultimate strength was detected between the two fixation groups. CONCLUSIONS: This study showed that fixation of an intra-articular fracture of the distal part of a cadaveric radius with biocompatible calcium-phosphate bone cement produced results that were biomechanically comparable with those produced by fixation with Kirschner wires. However, the constructs that were fixed with calcium-phosphate bone cement demonstrated less shortening under simulated cyclic load-bearing.  相似文献   
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