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11.
12.
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献
13.
The 16189 variant of mitochondrial DNA occurs more frequently in C282Y homozygotes with haemochromatosis than those without iron loading 总被引:3,自引:1,他引:3
Livesey KJ Wimhurst VL Carter K Worwood M Cadet E Rochette J Roberts AG Pointon JJ Merryweather-Clarke AT Bassett ML Jouanolle AM Mosser A David V Poulton J Robson KJ 《Journal of medical genetics》2004,41(1):6-10
Background:Patients with hereditary haemochromatosis (HH) are usually homozygous for the C282Y mutation in the HFE gene. They have variable expression of iron overload and present with a variety of complications, including liver disease, diabetes, arthropathy, fatigue, and cardiomyopathy. The mitochondrial 16189 variant is associated with diabetes, dilated cardiomyopathy, and low body fat at birth, and might contribute to genetic predisposition in further multifactorial disorders. The objective of this study was to determine the frequency of the 16189 variant in a range of patients with haemochromatosis, who had mutations in the HFE gene.
Methods:Blood DNA was analysed for the presence of the 16189 variant in British, French, and Australian C282Y homozygotes and controls, with known iron status, and in birth cohorts.
Results:The frequency of the mitochondrial 16189 variant was found to be elevated in individuals with haemochromatosis who were homozygous for the C282Y allele, compared with population controls and with C282Y homozygotes who were asymptomatic (42/292 (14.4%); 102/1186 (8.6%) (p = 0.003); and 2/64 (3.1%) (p = 0.023), respectively).
Conclusions:Iron loading in C282Y homozygotes with HH was exacerbated by the presence of the mitochondrial 16189 variant.
相似文献14.
Long-term results of valve replacement using antibiotic-sterilised homografts in the aortic position
S.M. Langley S.A. Livesey V.T. Tsang D.J. Barron R.K. Lamb J.K. Ross Sir J.L. Monro 《European journal of cardio-thoracic surgery》1996,10(12):1097-1106
Objective.
Antibiotic-sterilised homograft valves stored at 4 °C have been implanted in the subcoronary position in this unit since 1973. This study was undertaken in order to assess the longterm function of these valves.Methods.
All 249 patients undergoing homograft aortic valve replacement (AVR) at the Wessex Cardiothoracic Centre between April 1973 and December 1994 were studied. Homograft valve sizes ranged from 15 mm to 28 mm internal diameter, 202 (81.1%) varying between 18 mm and 22 mm. The mean patient follow-up was 12.4 years with a total follow-up of 3096 patient-years. There were six early deaths (2.4%).Results.
On actuarial analysis, survival was 78.5 ± 2.7% (1SE) at 10 years, 65.7 ± 3.3% at 15 years and 55.0 ± 3.9% at 20 years. The freedom from redo AVR was 87.9 ± 2.4% at 10 years, 71.7 ± 3.8% at 15 years and 49.7 ± 5.6% at 20 years. The freedom from structural degeneration was 85.5 ± 2.5% at 10 years, 63.6 ± 4.0% at 15 years and 41.9 ± 6.4% at 20 years. On multivariate analysis the risk of valve failure was significantly higher in younger patients (P < 0.0001) and in those who underwent aortic root tailoring (P = 0.024). The freedom from endocarditis was 98.4 ± 0.9% at 10 years, 96.2 ± 1.6% at 15 years and 95.1 ± 1.9% at 20 years. Of the 249 patients, 218 had an isolated homograft AVR and were not anticoagulated. In this group there were two possible thromboembolic events.Conclusion.
As well as the established haemodynamic benefits, this study has shown that homograft AVR with antibiotic-sterilised 4 °C stored homograft valves implanted in the subcoronary position, offers good long-term results. 相似文献15.
Marrow regeneration after mechanical depletion 总被引:1,自引:0,他引:1
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration. 相似文献
16.
A 15 year old boy with autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy syndrome suffered recurrent episodes of severe intractable diarrhoea, steatorrhoea, and hypocalcaemia. The only treatment modality, which controlled the malabsorption syndrome, was immunosuppression with intravenous high dose methylprednisolone and oral methotrexate maintenance therapy. 相似文献
17.
Colonic fermentation of organic matter to short-chain fatty acids has been implicated in the improvement in insulin sensitivity achieved by feeding diets rich in complex carbohydrates. The present study assessed the potential role of the colon in determining postprandial glucose kinetics. Metabolic responses to a complex-carbohydrate test meal were determined in conjunction with a primed continuous infusion of D-[6,6-2H]glucose in a group of ileostomists and sex-matched controls. Glucose disposal (GD) was computed using Steele's (1959) non-steady-state kinetics on a single compartment model. Insulin sensitivity was derived using cumulative GD as the dependent variable, and time and the integrated insulin concentration as independent variables. The ileostomist group had a significantly higher postprandial plasma insulin concentration ( P = 0.034) compared with the control group, but no difference in the plasma glucose concentration. Total GD was similar in each group, although the insulin-dependent GD was substantially lower in the ileostomists (0.46 v. 0.13 mg glucose/min per pmol, P = 0.015). The ileostomist group also showed a 50% lower rate of glucose oxidation in the postprandial period (p = 0.005), although the rate of non-oxidative GD was not significantly affected. The present study indicates that loss of the colon is associated with several characteristics of the insulin resistance syndrome, and favours a view that the colon has a role in the control of postprandial glucose. 相似文献
18.
Wang WS; Hsieh RK; Chiou TJ; Liu JH; Fan FS; Yen CC; Tung SL; Chen PM 《Japanese journal of clinical oncology》1998,28(9):551-554
A 54-year-old man was treated with weekly 24-h infusion of high-dose
5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon
cancer. At first, he tolerated the treatment well and no significant
toxicity was identified. After a total of eight courses of treatment, a
stable disease was observed, but mild shortness of breath was found on
occasion. The patient had no previous history of cardiac disease and the
heart performance assessed by left ventricular ejection fraction before
treatment was normal. Unfortunately, acute pulmonary edema with lethal
cardiogenic shock occurred during the ninth course of treatment, in spite
of intensive medical treatment. The chest X-ray showed extreme
cardiomegaly. Repeated assessment of his heart function by echocardiogram
and ventricular ejection fraction revealed a very poor cardiac performance.
Toxic cardiogenic shock during weekly 24-h infusion of high-dose
5-fluorouracil and leucovorin is extremely rare. To the best of our
knowledge, no case has been reported in the English literature. We report a
case and the relevant literature about the incidence, clinical picture and
possible pathophysiology on 5-fluorouracil-related cardioxicity is
reviewed.
相似文献
19.
Marcel JH Aries Adnan Aslan Jan Willem J Elting Roy E Stewart Jan G Zijlstra Jacques De Keyser Patrick CAJ Vroomen 《Journal of clinical nursing》2012,21(13-14):1825-1830
Background. Routine lateral turning of patients has become an accepted standard of care to prevent complications of immobility. The haemodynamic and oxygenation effects for patients in both lateral positions (45°) are still a matter of debate. We aimed to study the effect of these positions on blood pressure, heart rate and oxygenation in a general intensive care population. Design. Observational study. Method. Twenty stable intensive care unit patients had intra‐arterial blood pressure recordings in the supine and lateral positions with the correction of hydrostatic height compared with a fixed reference point (phlebostatic level). A multilevel model was used to analyse the data. Results. Mean arterial pressure readings in the lateral positions were, on average, 5 mmHg higher than in the supine position (p < 0·001). There were no significant differences between mean arterial pressure recordings in the left and right lateral position (p = 1·0). No important differences in oxygenation and heart rate were observed. After correction for covariates, the effects persisted. Conclusion. Our study demonstrated an increase, albeit small, in blood pressure in the lateral positions. No major differences between the left and right lateral position were found. No important differences in oxygenation and heart rate were observed. Relevance to clinical practice. Turning haemodynamically stable patients in the intensive care unit has no important effects on blood pressure measurements when continuous hydrostatic height correction is applied. 相似文献
20.