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41.
Ambulatory blood pressure in patients with Parkinson's disease without and with orthostatic hypotension 总被引:1,自引:0,他引:1
Jean-Michel Senard Bernard Chamontin André Rascol Jean-Louis Montastruc 《Clinical autonomic research》1992,2(2):99-104
Non-invasive ambulatory recordings of blood pressure and heart rate were performed using a Spacelabs device during day and night periods in patients with Parkinson's disease with (n = 19) or without orthostatic hypotension (n = 19). In patients with orthostatic hypotension, the average systolic and diastolic blood pressure during the night (137 ± 5/80 ± 3 mmHg) was higher (p < 0.05) than during the day period (121 ± 3/76 ± 2 mmHg). In patients without orthostatic hypotension, a decrease in blood pressure was recorded during the nocturnal period. In patients with orthostatic hypotension, the blood pressure variability was higher (p < 0.05) during the day (systolic: 14.6 ± 1.3%; diastolic: 16.5 ± 1.0%) than during the night (systolic: 9.1 ± 0.8%; diastolic: 10.8 ± 1.1%). The blood pressure load (percentage of values above 140/90 mmHg) during the night was significantly higher than during the day for both systolic (41.2 ± 8.1 vs. 19.6 ± 4.7%) and diastolic blood pressure (24.9 ± 6.9 vs. 16.3 ± 4.9%). There was a decrease in heart rate in both groups during the night. A fall of 25 mmHg or more in systolic blood pressure after meals occurred in ten patients with orthostatic hypotension and in one patient without orthostatic hypotension. These results indicate that orthostatic hypotension in Parkinson's disease is associated with specific modifications of ambulatory blood pressure including loss of circadian rhythm of blood pressure, increased diurnal blood pressure variability and post-prandial hypotension. 相似文献
42.
Alan G. Fraser Peter T. Buser Jeroen J. Bax Willem R. Dassen Petros Nihoyannopoulos Jürg Schwitter Juhani M. Knuuti Martin Höher Frank Bengel András Szatmári 《European journal of nuclear medicine and molecular imaging》2006,33(8):955-959
Advances in medical imaging now make it possible to investigate any patient with cardiovascular disease using multiple methods which vary widely in their technical requirements, benefits, limitations and costs. The appropriate use of alternative tests requires their integration into joint clinical diagnostic services where experts in all methods collaborate. This statement summarises the principles that should guide developments in cardiovascular diagnostic services.This paper is published simultaneously in the European Heart Journal (2006;27:1750–1753) and in the European Journal of Echocardiography (2006;7:268–273). 相似文献
43.
44.
Objective To describe the different imaging modalities used for the diagnosis and classification of hydrocephalus, their role in defining
the optimal treatment of hydrocephalus and to define the optimal preoperative diagnostics for endoscopic third ventriculocisternostomy
(ETV).
Methods An overview on available imaging modalities for hydrocephalus will be given and their pros and cons discussed. In addition,
different aspects of the treatment of hydrocephalus by shunts and by ETV will be highlighted.
Discussion The role of the technical aspects of performing an ETV, the role of the surgeon’s philosophy, the role of the urgency of the
procedure, and the role of informed consent on the requirements for the imaging of the hydrocephalus will be discussed.
Conclusion The authors conclude that MRI is a conditio sine qua non for ETV in elective surgical cases. 相似文献
45.
Siamak Mohammadi Emre Belli Ivo Martinovic Lucile Houyel André Capderou Jérome Petit Claude Planché Alain Serraf 《European journal of cardio-thoracic surgery》2005,28(2):217-222
OBJECTIVE: To identify the surgical approaches and risk factors which influence longevity of right ventricle to pulmonary artery (RV-PA) conduits following first reoperation for obstruction. METHODS: Between January 1993 and August 2003, 114 patients underwent 141 reoperations for RV-PA conduit obstruction. Diagnoses included 'Truncus Arteriosus' (n=52), 'Pulmonary atresia/Tetralogy of fallot' (n=39), 'Double outlet right ventricle' (n=10), 'Transposition of great arteries, VSD, and pulmonary atresia' (n=9), and the 'Ross operation' (n=4). All patients had undergone a previous biventricular repair. The first reoperation for conduit obstruction was performed in 112 hospital survivors by: total conduit replacement (Group A, n=73) with valved (homograft=10 and xenograft=54) or non-valved (n=9) conduit, and patch enlargement of the obstructed RV outflow tract with preservation of the posterior and sides of the conduit wall after removing of the fibrocalcific peel and degenerated valve (Group B, n=39). Mean age at first reoperation was 8.8+/-6.7 and 7.5+/-5.3 years in patients of groups A and B, respectively. Seven patients in Group A and 18 in Group B required a second reoperation and two patients in Group B a third reoperation. RESULTS: There were two hospital deaths and no late deaths. Mean follow-up was 5.8+/-3.2 years. Risk factors for second reoperation by univariate analysis were: homograft conduit use (P=0.004), Group B surgical approach (P=0.0001), higher RV-PA systolic pressure gradient at discharge (P=0.02), and age <5-years-old (P=0.01). Multivariate analysis showed that inclusion in Group B and younger age (<5-years-old) at repair were independent risk factors for second reoperation. Group B surgical approaches had higher RV-PA systolic pressure gradient at discharge (P=0.02) and required more PA bifurcation repair at the time of second reoperation (P=0.05). Freedom from second reoperation for conduit obstruction was significantly higher in Group A patients at 5 and 8 years (P<0.04) and those with xenografts rather than homograft (P=0.04). CONCLUSIONS: Our results support the optimal surgical approach for RV-PA conduit obstruction is total replacement with a xenograft. RV outflow reconstruction by other techniques without complete dissection of PA bifurcation does not completely relieve the stenosis and could cause early restenosis. Higher systolic gradients at discharge and younger age at first reoperation are predictors of earlier reoperation. 相似文献
46.
Biocompatibility studies of the Anaconda stent-graft and observations of nitinol corrosion resistance. 总被引:3,自引:0,他引:3
Robert Guidoin Yvan Douville Michel F Baslé Martin King Georgi R Marinov Amidou Traoré Ze Zhang Fabien Guillemot Guy Dionne Ruwan Sumanasinghe André-Pierre Legrand Marie-France Guidoin Marie-Christine Porté-Durrieu Charles Baquey 《Journal of endovascular therapy》2004,11(4):385-403
PURPOSE: To validate the deployment, in vivo performance, biostability, and healing capacity of the Anaconda self-expanding endoprosthesis in a canine aortic aneurysm model. METHODS: Aneurysms were surgically created in 12 dogs by sewing a woven polyester patch onto the anterior side of the thoracic or abdominal aorta. Anaconda prostheses were implanted transfemorally for prescheduled periods (1 or 3 months). Aneurysm exclusion and stent-graft patency were monitored angiographically. Healing was assessed with histological analysis and scanning electron microscopy (SEM). Textile analysis determined the physical and chemical stability of the woven polyester material, while the biostability of the nitinol wires was evaluated with SEM and spectroscopy. RESULTS: All prostheses were intact at explantation. After 1 month, endothelial-like cells were migrating in a discontinuous manner both proximally and distally over the internal collagenous pannus at the device-host boundary. After 3 months, endothelialization had reached the midsections of the devices, with a thicker collagenous internal capsule. Patches of endothelial-like cells were sharing the luminal surface with thrombotic deposits. However, the wall of the device at the level of the aneurysm was generally poorly healed, with multiple thrombi scattered irregularly over the luminal surface. The polyester fabric was intact except for some filaments that were ruptured adjacent to the sutures and some abrasion caused by the nitinol wires. No evidence of corrosion was found on the nitinol stents. CONCLUSIONS: This Anaconda stent-graft has demonstrated its ability to exclude arterial aneurysms. The device used in this study was an experimental prototype, and the manufacturer has incorporated new immobilization features into the model for clinical use. The constituent materials appear to be suitable in terms of biocompatibility, biofunctionality, and short-term durability. 相似文献
47.
Gregor Warnecke Murat Avsar Thomas Steinkamp Renate Reinhard Jost Niedermeyer André R Simon Axel Haverich Martin Strüber 《European journal of cardio-thoracic surgery》2005,28(3):454-460
OBJECTIVE: Tacrolimus has been shown to provide superior immunosuppression in various solid organ transplant settings. The purpose of our study was to compare the survival of porcine lung allografts after induction with either cyclosporine A (CsA) or tacrolimus. METHODS: Single lung transplantation from MHC mismatched donors was performed in 10 minipigs. Immunosuppression included 1.5 mg/kg per day methylprednisolone and 1.0 mg/kg per day azathioprine. CsA (n=5) was adjusted to trough levels of 300-500 ng/ml, tacrolimus (n=5) was adjusted to 16-26 ng/ml. All immunosuppressive drugs were discontinued on postoperative day (POD) 28. Allograft survival was monitored by sequential chest radiographs, bronchoscopy and transbronchial biopsy histology. Peripheral blood leukocytes were scanned for donor chimerism and CD3, CD4, CD8 and CD25 expression. RESULTS: The animals survived a 4-week course of immunosuppression without radiological or histological signs of rejection on POD 28. Median allograft survival in CsA-treated animals was 55+/-15 days and all animals rejected their grafts within 42 days after withdrawal of immunosuppression. In tacrolimus-treated animals, median survival was 152+/-65 days with the longest survivor being electively sacrificed on POD 390 (P=0.0064). The degree of donor leukocyte chimerism and the frequency of CD4+CD25+ T-cells were higher in the tacrolimus group, however, these differences were not statistically significant. CONCLUSION: The results of our study show that primary immunosuppression with tacrolimus is superior to cyclosporine after pulmonary allotransplantation in a large animal model. 相似文献
48.
This article presents normal EEG characteristics and their maturational pattern in premature infants of 24-30 weeks gestational age. Although the very premature infants with a normal outcome are not that numerous, their normal EEG pattern should be known, as EEG constitutes a basis for neurological prognosis. Background activity is first discontinuous but the discontinuity gradually decreases and the activity is completely continuous at 30 weeks of age, during active sleep. At the same time, interburst intervals become shorter so that the proportion of time without EEG activity decreases. Based on EEG activity and eyes movements, a rough sleep state differentiation appears as early as 25 weeks of gestational age and is complete at 30 weeks. The main EEG figures are high-voltage delta waves, whose frequency is slower and amplitude higher in younger infants. Temporal delta waves occur in sequences and are characteristic of the very premature infant; they progressively become smaller and less numerous and disappear around 27-28 weeks. In contrast, occipital delta waves remain numerous; they are of high voltage and usually bilaterally superimposed with fast rhythms. Both types of frontal delta waves that are seen in 24-27 weeks premature babies disappear with maturation. Bursts of synchronized delta waves, which are less numerous than localized delta waves, also disappear before 28 weeks of gestational age. Finally, diffuse theta bursts which are mainly recorded at 26-27 weeks, progressively focus on temporal areas with maturation. At 30 weeks, they are observed on temporal areas, mainly during slow-wave sleep. 相似文献
49.
J L André 《Annales de pédiatrie》1991,38(6):376-380
As soon as blood pressure (BP) values are available for a child or teenager, a multitude of questions arise. The values obtained need to be interpreted, validated, and made use of. Values measured in an individual can be interpreted only by comparison with the results of measurements performed using the same protocol in an adequate sample of subjects with similar life styles. The value of reference to stature rather than age has been well established. Studies of BP measured at rest are the most widely used. The validity of blood pressure values is dependent on measurement technique but is also related to the problem of intraindividual variability. To address this problem, blood pressure values have been measured not only at rest but also during standardized stimulation tests and throughout the 24-hour period (ambulatory BP measurements). Studies using these techniques in children and adolescents are still scant. Longitudinal studies of the mean-term and long-term reproducibility of these measurements are needed. Until results of such studies are available, blood pressure measurements in non-resting subjects will be mainly useful for evaluating patients with borderline BP values at rest and for monitoring the effect of therapy. The response to blood pressure values believed to be borderline should include evaluation of factors which influence BP values as well as of the other risk factors for cardiovascular disease. The predictive value of blood pressure levels is fairly poor in childhood. Correlation coefficients between values obtained five years apart approximate 0.25. These coefficients increase with age and finally level off at 0.4-0.5.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
50.