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991.
Sierra Farris PA‐C MPAS Paul Ford PhD Joseph DeMarco PhD Monique L Giroux MD 《Movement disorders》2008,23(14):1973-1976
Deep brain stimulation (DBS) is an effective neurosurgical treatment for patients with advanced Parkinson's disease (PD) suffering from motor complications that are refractory to further medication management. DBS requires an invasive procedure of implanting brain electrodes while awake, followed by implantation of neurostimulators under general anesthesia. The neurostimulator requires battery monitoring and replacement approximately every 3 to 5 years. These two elements of the technology provide numerous decision points about continuing therapies that can involve ethical choices. Although motor function can be improved with subthalamic nucleus (STN) DBS, the long‐term risks of living with implanted hardware should be carefully evaluated for patients with diminishing cognitive capacity. We describe two cases where ethical dilemmas occurred postoperatively as a result of cognitive decline and describe salient ethical dimensions that illustrate the need for a proactive postoperative plan for supervision as a prerequisite for surgery to include neuropsychological testing to predict the likelihood of net benefit to the patient and family beyond just motor improvement. © 2008 Movement Disorder Society 相似文献
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Summary Recent clinical and epidemiological studies have emphasised the importance of the patello-femoral joint (P-FJ) in osteoarthritis. X-ray examination of this joint for joint space width (JSW) assessment using the standard medio-lateral view is difficult. In 26 femora, the mean angle of inclination between the medial and lateral condyles measured at their inferior and anterior surfaces, relative to a line passing between the medial and lateral femoral epicondyles, was used to define the optimum alignment of the x-ray tube. The results showed that for medio-lateral radiography of the P-FJ, the central ray of the x-ray beam should be directed cranially, in a upward projection by 5° and then anteriorly by 4°, resulting in superimposition of the inferior and anterior condylar surfaces respectively. The value of these angles was confirmed by radiographs of the 26 femora and 10 post mortem joints. The margins for joint space width measurement were identified by embedding lead balls, within the cartilage of the cadaveric knees, and were defined as the median vertical ridge of the patella and the middle of the patella groove on the femur.
Une position radio-anatomique pour la radiographie de profil de l'articulation fémoro-patellaire humaine
Résumé De récentes études cliniques et épidémiologiques ont souligné l'importance de l'articulation fémoropatellaire (AFP) dans l'arthrose du genou. L'examen radiographique de cette articulation, notamment pour l'appréciation de l'épaisseur de l'interligne articulaire en incidence médiolatérale de routine, est difficile. Sur 26 fémurs, l'angle moyen d'inclinaison des surfaces inférieure et antérieure des condyles latéral et médial par rapport à une ligne unissant les deux épicondyles a été utilisé pour définir l'alignement optimal du tube radiogène. Les résultats ont montré que pour une radiographie médio-latérale de l'AFP, le faisceau central de rayons X devait être dirigé crânialement de 5°, et antérieurement de 4°, permettant ainsi d'obtenir la superposition des deux condyles. La validité de ces angles a été confirmée par les radiographies de 26 fémurs et de 10 articulations cadavériques. Les repères pour la mesure de l'épaisseur de l'interligne articulaire, identifiés par l'insertion de billes de plomb dans le cartilage des articulations cadavériques, ont été définis comme étant la crête verticale médiane de la patella et le milieu de la gorge patellaire du fémur.相似文献
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996.
G Bosi JP Lintermans PA Pellegrino G Svaluto-Moreolo A Vliers 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(8):928-931
The aim of the present study is to contribute to the knowledge of the natural history of cardiac rhabdomyoma in children with and without tuberous sclerosis. In a retrospective study, 33 children with cardiac rhabdomyoma were collected from three pediatric cardiology centres. In 30/33 patients tuberous sclerosis was associated. High prevalence of cardiac rhabdomyoma was found in infancy, with 21/23 detected before the age of 1 year, and 11/33 before 1 month of age. Cardiac manifestations were present in 19 patients: cardiac rhythm disturbances were detected in 13; in 6/33 a Wolff-Parkinson-White syndrome was documented, of which 4 presented paroxysmal arrhythmias. Obstructive or regurgitative phenomena were present in 5; and in 2 patients surgical removal proved necessary. With the exception of one tumoural mass in the right atrium, all 77 tumours were located somewhere in the ventricles, including at atrioventricular valve level. Because of spontaneous regression of most of the tumoural masses, treatment should at first be symptomatic, while surgical removal is required only in life-threatening conditions, as documented in 2 of our 33 patients. 相似文献
997.
In rabbits receiving a normal laboratory diet the platelet half-life was 40.4 ± 2.5h (mean ± S.D., N=35). In animals fed the cholesterolenriched diet for 12 weeks the platelet half-life was reduced to 31.6 ± 3.6h (mean ± S.D., N=35). Treatment of cholesterol-fed animals with a single daily dose of CGS 12970 (a long acting inhibitor of thromboxane synthase) normalised the platelet half-life. Single daily doses of the relatively shorter acting thromboxane synthase inhibitors (CGS 13080 and dazoxiben) failed to correct the reduced platelet survival. However, twice daily dosing with dazoxiben was effective. The cyclooxygenase inhibitors, aspirin and sulphinpyrazone, failed to correct the reduced platelet survival. 相似文献
998.
Summary— The influence of various vasodilator and constrictor drugs was studied in isolated mesenteric arteries obtained from obese and lean Zucker rats. The obese Zucker rats were moderately hypertensive and their isolated small arteries were not hypertrophied. All vasoconstrictor agents studied (noradrenaline, methoxamine, serotonin, calcium chloride, potassium chloride) caused the same effects in isolated arteries taken from obese and lean (control) Zucker rats, respectively. In vessels from obese Zucker rats, the vasodilator responses to sodium nitroprusside, methacholine, the K+-channel opener cromakalim and nifedipine were the same as in control preparations. In conclusion, isolated mesenteric arteries from obese Zucker rats do not show relevant structural changes, and the pharmacodynamic behaviour of such vessels appears to be the same as that of control preparations. Neither the diabetic hyperinsulinaemic state nor the hyperlipoproteinaemia in the obese Zucker rats appear to cause serious vascular damage. 相似文献
999.
Summary— Endothelium-dependent relaxation has been demonstrated to be involved in the regulation of vascular tone and extracellular Ca2+ was found to play a prominent role in this process. Since the dependency on extracellular Ca2+ appeared to differ considerably within the arterial tree, possibly as a consequence of vessel-related endothelium-dependent mechanisms, we investigated the effects of different compounds affecting Ca2+ entry (nifedipine, CoCl2) on angiotensin II-induced contractions of rat aortic rings with and without endothelium as well as the responses in a Ca2+–“free” solution. For this purpose, rat aortic rings were either undone from their endothelial layer by gentle mechanical rubbing or care was taken to keep the intima intact in case rings where endothelium were required. The presence of an intact endothelium was confirmed by acetylcholine-induced relaxation. A stronger responsiveness towards angiotensin I, both after a complete concentration-response curve and after a single maximal concentration of angiotensin II was observed in arterial segments without endothelium. The maximal contraction to a single concentration of angiotensin II (0.1 μM) in the rings without endothelium amounted to 75.8 ± 3.8% of the preceding response to a supramaximal concentration of noradrenaline (= Emax). In rings without the endothelial layer, the contraction was 34.8 ± 3.7% of Emax. This indicates an endothelium-induced relaxation in aortic rings with endothelium. After incubation with the Ca2+ entry blocker nifedipine (1 μM) both rings with and without endothelium were inhibited to the same extent, contractions amounted to 30.7 ± 1.8% and 19.6 ± 1.3% of Emax, respectively. However, incubation in a Ca2+-“free” medium for 5 min resulted in similar contractions for rings without endothelium (16.4 ± 1.4% of Emax) as for rings with endothelium (15.0 ± 1.6% of Emax). Moreover, CoCl2 in a concentration of 300 μM hardly inhibited the contraction of rings with an intact endothelium, a contractile response of 30.5 ± 2.8% of Emax was observed. The results of the study suggest that the influx of Ca2+ions is indeed responsible for the endothelium-mediated relaxation. However, this influx, which cannot be antagonized by nifedipine, but has shown to be affected by CoCl2, suggests that channels intensitive to organic Ca2+ entry blockers may be involved. 相似文献
1000.