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排序方式: 共有497条查询结果,搜索用时 15 毫秒
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Edgardo Pezzetta Alexandre Paroz Hans-Beat Ris Olivier Martinet 《European journal of cardio-thoracic surgery》2003,23(6):1062-1064
Spontaneous hemothorax is a rare and life threatening complication of neurofibromatosis. Two types of vascular involvement have been described: (a) stenotic or aneurysmal alterations in large vessels such as the aorta and its branches; and (b) dysplastic features in smaller vessels. Thoracotomy and surgical ligation of the bleeding vessels is primarily indicated in the presence of active bleeding with associated hemodynamic compromise. A more conservative approach with endovascular embolization or non-operative management have also been reported in case of hemodynamic stability. We present a rare case of spontaneous hemothorax treated conservatively in a patient with von Recklinghausen's disease. 相似文献
3.
Rolf Inderbitzi Markus Furrer Christian Klaiber Hans Beat Ris Heinz Striffeler Ulrich Althaus 《Surgical endoscopy》1992,6(4):189-192
Summary Thoracoscopic surgery is decidedly expanded by the ability to perform pulmonary wedge resections of the lung by using the Endo-GIA-stapler. In addition to thoracoscopic biopsies, since July 1991 we have carried out wedge resections in 12 patients suffering from spontaneous pneumothorax (nine) or peripheral bronchial carcinoma (three). Postoperatively one air fistula persisted over 9 days. The chest tube was removed within 48 h in all other patients. There was no other major complication. The postoperative hospitalization period lasted 4.6 days (1–9 days). Operating time was 44 min (30–70 min). The benefit for the patient consists in the little-impaired breathing mechanics, the short hospital stay, and the favorable cosmetic result. 相似文献
4.
Summary This study evaluates local variations of the cerebral vasomotor responses to hypercapnia and haemorrhagic hypotension in a pig model. Four laser Doppler flow probes were used in each pig. There was considerable variation in laser Doppler signals between the four probes in baseline recordings. The increases in flow after CO2 administration in 7 pigs had a mean coefficient of variation of 0.43 ± 0.31, and the flow changes after blood loss in another 7 pigs had a mean coefficient of variation of 0.45 ± 0.34. The range of flow changes within each animal was large; the probe with the highest CO2 response showed on the average a 273% ± 157% larger CO2 response than the probe with the lowest CO2 response. Correspondingly, the probe with the best preserved blood flow after blood loss had on the average a flow value of 93% ± 12% of the baseline value, while the probe that changed most with haemorrhage had a flow value of 44% ± 24% of the baseline value. Single laser Doppler recordings have been used for the monitoring of cerebral blood flow in neurosurgical critical care, but our results suggest that a single laser Doppler flow probe is not an adequate method to monitor vasoreactivity in neurosurgical patients because flow signals from one probe may be unrepresentative for other sites in the brain. 相似文献
5.
Blood velocities in 12 arteries were recorded by an ultrasonic doppler flowmeter in 11 young adults. Two major types of velocity patterns existed at rest. In certain arteries (the common carotid, the external carotid, the superficial temporal and the proper palmar digital arteries) flow was towards the periphery throughout the entire pulse cycle. Other arteries (the common femoral, the popliteal, the posterior tibial and the pedal artery) exhibited retrograde flow in part of the pulse cycle. In each individual a spontaneous variation between these two velocity patterns was observed in the subclavian, the axillary, the brachial and the radial artery. The velocity pattern of each artery is described, and absolute blood velocities at recognizable instances during the pulse cycle are given. The influence of peripheral resistance on the velocity pattern was investigated by reactive hyperaemia of the femoral artery. We find that not only is there an upward displacement of the resting femoral curve relative to the line of zero, but the shape of the velocity pattern is also changed. Our conclusion is that peripheral resistance is of major importance not only for the mean velocity, but also for the shape of the velocity pattern in the artery. 相似文献
6.
Ris L Hachemaoui M Vibert N Godaux E Vidal PP Moore LE 《Journal of neurophysiology》2001,86(2):703-716
The modulation of action potential discharge rates is an important aspect of neuronal information processing. In these experiments, we have attempted to determine how effectively spike discharge modulation reflects changes in the membrane potential in central vestibular neurons. We have measured how their spike discharge rate was modulated by various current inputs to obtain neuronal transfer functions. Differences in the modulation of spiking rates were observed between neurons with a single, prominent after hyperpolarization (AHP, type A neurons) and cells with more complex AHPs (type B neurons). The spike discharge modulation amplitudes increased with the frequency of the current stimulus, which was quantitatively described by a neuronal model that showed a resonance peak >10 Hz. Modeling of the resonance peak required two putative potassium conductances whose properties had to be markedly dependent on the level of the membrane potential. At low frequencies (< or =0.4 Hz), the gain or magnitude functions of type A and B discharge rates were similar relative to the current input. However, resting input resistances obtained from the ratio of the membrane potential and current were lower in type B compared with type A cells, presumably due to a higher level of active potassium conductances at rest. The lower input resistance of type B neurons was compensated by a twofold greater sensitivity of their firing rate to changes in membrane potential, which suggests that synaptic inputs on their dendritic processes would be more efficacious. This increased sensitivity is also reflected in a greater ability of type B neurons to synchronize with low-amplitude sinusoidal current inputs, and in addition, their responses to steep slope ramp stimulation are enhanced over the more linear behavior of type A neurons. This behavior suggests that the type B MVNn are moderately tuned active filters that promote high-frequency responses and that type A neurons are like low-pass filters that are well suited for the resting tonic activity of the vestibular system. However, the more sensitive and phasic type B neurons contribute to both low- and high-frequency control as well as signal detection and would amplify the contribution of both irregular and regular primary afferents at high frequencies. 相似文献
7.
8.
Colli S Lalli M Risè P Mussoni L Eligini S Galli C Tremoli E 《Thrombosis and haemostasis》1999,81(4):576-581
This study investigated whether spontaneous lipid enrichment of human macrophages affects their thrombogenic potential as measured by increased production of tissue factor (TF) and plasminogen activation inhibitor types 1 and 2 (PAI-1 and PAI-2). Macrophages were obtained following a 7-day culture period of monocytes, isolated from the same donor, in autologous serum (HS) or in fetal bovine serum (FBS). Those cultured in HS underwent marked lipid accumulation relative to those cultured in FBS that was accompanied by increased production of TF and PAI-1, but not of PAI-2, and decreased production of interleukin-1beta. They also contained more arachidonic and linoleic acid and lower amounts of n-3 polyunsaturated fatty acids, particularly docosahexaenoic acid (22: 6). These data indicate that the transformation of macrophages into foam cells results in an increase in their thrombogenic and antifibrinolytic potential and provide a possible explanation of the thrombotic sequelae frequently consequent on plaque fissuring and disruption. 相似文献
9.
Proton magnetic resonance spectroscopy pattern of progressive multifocal leukoencephalopathy in AIDS 总被引:3,自引:0,他引:3
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Iranzo A Moreno A Pujol J Martí-Fàbregas J Domingo P Molet J Ris J Cadafalch J 《Journal of neurology, neurosurgery, and psychiatry》1999,66(4):520-523
The objective was to determine whether the use of intermediate echo times (135 ms) in proton magnetic resonance spectroscopy (1H-MRS) detects a homogenous pattern in progressive multifocal leukoencephalopathy (PML) in HIV-1 infected people, and to confirm the results of previous studies. Six patients infected with HIV-1, with PML established by biopsy, and six healthy age and sex matched volunteers were evaluated to define their spectroscopic pattern. 1H-MRS spectra performed at 1.5 T were obtained with the STEAM sequence: TE/TM/TR, 20 ms/13.7 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (STEAM-20) and with the PRESS sequence; TE/TR, 135 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (PRESS-135). A single voxel was placed on the lesions and on the parieto-occipital white matter of controls. The peaks of N-acetylaspartate (NAA), choline (Cho), myoinositol (mI), lactate, and lipids were considered, and the results were expressed using creatine as reference. Spectra of PML lesions were characterised by significantly reduced NAA, lactate presence, and by significantly increased Cho and lipids compared with control group values. These results indicate that 1H-MRS detects a homogenous pattern in PML lesions. Recent studies, together with this, suggest that 1H-MRS may help in the diagnostic approach to patients with suspected PML lesions associated with AIDS. 相似文献
10.
Prognostic relevance of Masaoka and Müller-Hermelink classification in patients with thymic tumors 总被引:2,自引:0,他引:2
Lardinois D Rechsteiner R Läng RH Gugger M Betticher D von Briel C Krueger T Ris HB 《The Annals of thoracic surgery》2000,69(5):1550-1555
BACKGROUND: To compare the prognostic relevance of Masaoka and Müller-Hermelink classifications. METHODS: We treated 71 patients with thymic tumors at our institution between 1980 and 1997. Complete follow-up was achieved in 69 patients (97%) with a mean follow up-time of 8.3 years (range, 9 months to 17 years). RESULTS: Masaoka stage I was found in 31 patients (44.9%), stage II in 17 (24.6%), stage III in 19 (27.6%), and stage IV in 2 (2.9%). The 10-year overall survival rate was 83.5% for stage I, 100% for stage IIa, 58% for stage IIb, 44% for stage III, and 0% for stage IV. The disease-free survival rates were 100%, 70%, 40%, 38%, and 0%, respectively. Histologic classification according to Müller-Hermelink found medullary tumors in 7 patients (10.1%), mixed in 18 (26.1%), organoid in 14 (20.3%), cortical in 11 (15.9%), well-differentiated thymic carcinoma in 14 (20.3%), and endocrine carcinoma in 5 (7.3%), with 10-year overall survival rates of 100%, 75%, 92%, 87.5%, 30%, and 0%, respectively, and 10-year disease-free survival rates of 100%, 100%, 77%, 75%, 37%, and 0%, respectively. Medullary, mixed, and well-differentiated organoid tumors were correlated with stage I and II, and well-differentiated thymic carcinoma and endocrine carcinoma with stage III and IV (p < 0.001). Multivariate analysis showed age, gender, myasthenia gravis, and postoperative adjuvant therapy not to be significant predictors of overall and disease-free survival after complete resection, whereas the Müller-Hermelink and Masaoka classifications were independent significant predictors for overall (p < 0.05) and disease-free survival (p < 0.004; p < 0.0001). CONCLUSIONS: The consideration of staging and histology in thymic tumors has the potential to improve recurrence prediction and patient selection for combined treatment modalities. 相似文献