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61.
In a prospective study we compared duplex-ultrasound characteristics of symptomatic internal carotid artery (ICA) stenoses with cranial computerized tomographic (CCT) findings in 82 patients suffering from completed or transient middle cerebral artery symptoms. The aim was to assess the pathogenic role of ICA plaque morphology and the potential embolic risk of ICA plaques. The degree of carotid stenosis was estimated by spectral analysis of the pulsed Doppler signal. The CCT findings were classified as being either normal, lacunar lesions, hemodynamically induced low-perfusion infarctions, or territorial embolic infarctions. According to their ultrasonic features we characterized the ICA plaque surface as smooth or irregular and their structure as homogeneous or heterogeneous. Plaques with an irregular surface and heterogeneous echogenicity dominated significantly in CCT-territorial infarctions (p < 0.01), whereas hemodynamically induced low-perfusion infarctions showed no relationship with any plaque characteristic. High degree ICA stenoses (> 50>%) dominated in both territorial infarctions and low-perfusion infarctions, as compared to ipsilateral normal CCT or lacunes (p < 0.05). Normal CCT and lacunar infarctions were associated with homogeneous and smooth plaques (both p < 0.05). We conclude that > 50% ICA stenoses can cause both hemodynamically induced low-perfusion infarctions as well as thromboembolic territorial infarctions, whereas ulcerated and heterogeneous plaques constitute a high risk factor for arterio-arterial embolic stroke. Furthermore, carotid ultrasound may help to estimate the clinical significance of carotid lesions.  相似文献   
62.
Mechanical femoral artery compression devices have several limitations. We compared a novel disposable beltheld pneumatic compression device to manual compression alone in 213 patients randomized into two equal groups. Both were comparable for age, gender, current therapy with aspirin (ASA) and warfarin, diameter of the arterial sheath, previous procedures via the same artery, procedure duration, and blood pressure. Manual compression time was 12 ± 3 minutes. Pneumatic compression was reduced during 60 minutes. Patient discomfort was assessed as none (82% vs 88%), mild (13% vs 8%), moderate (3% vs 4%), or severe (2% vs 0%) for the manual versus pneumatic group, respectively. Bleeding and hematoma occurred in 7.5% of patients with no difference between the treatment groups. However, manual compression was significantly more effective in the higher range of systolic blood pressure, and pneumatic in the lower range, with a cut point of approximately 170 mmHg. Predictors for bleeding were systolic blood pressure and dose of ASA. Among 113 patients with systolic blood pressure < 160 mmHg and low dose (75 mg) or no ASA, only / patient (0.9%) experienced bleeding while 31% of 16 patients with both elevated systolic blood pressure and high dose ASA (150–330 mg) bled. We conclude that pneumatic femoral artery compression does not reduce bleeding and hematoma compared with manual compression. The use of low dose (75 mg) or no ASA, as well as giving special attention to patients with elevated systolic blood pressure, may reduce the risk of bleeding after cardiac catheterization .  相似文献   
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64.
EMG responses in the external anal sphincter (EAS), the rectus abdominis muscle (RA), and the anterior tibial muscle (TA) were recorded following single magnetic transcranial cortical stimulations (TCCS) in seven healthy volunteers. The responses in the EAS differed from the responses in the other muscles. They had comparatively long durations ranging from 1 to 2 seconds, no inhibitory periods were observed, and there was no tendency for habituation to occur following a limited number of stimuli. The responses recorded in the EAS were used as test responses in order to evaluate the excitability changes in the EAS motoneurons occurring during bladder filling. Cystometries with filling rates of 15, 50 and 200 ml/min were done. During these cystometries TCCS were applied repeatedly, with constant strength, after each 50 ml of filling up to bladder capacity. The responses following TCCS changed in a highly reproducible way during bladder filling. After 100–200 ml of filling, the responses had longer latencies, diminished sizes, and shorter durations. When the filling reached a level 50–150 ml below capacity, the responses in most subjects again became greater and the latencies shorter. The changes were believed to be physiological. It was concluded that the EAS motoneurons are under both inhibitory and facilitatory influence during bladder filling in intact healthy humans. Facilitatory influences are often observed when the bladder is filled close to capacity. At lower bladder volumes the observed influence is always inhibitory. A decrease in the EMG activity of the EAS during filling cystometry should consequently not be regarded as a pathological response.  相似文献   
65.
Summary A neurological complication occurs in 40–60% of HIV infected patients during the course of the disease. In 10–20% the neurological complication is the first manifestation of the HIV infection. A reliable neuropathological diagnosis is a prerequisite for a specifically selected treatment. While modern computer-assisted imaging techniques, such as computed tomography or magnetic resonance imaging, do possess a high sensitivity, they do not as a rule permit an unambiguous diagnosis.Between October 1989 and July 1994 we biopsied 38 HIV infected patients stereotactically. The indication for the biopsy was determined by having radiologically detectable lesions with no regression tendency in patients under antitoxoplasmosis therapy. In 89% an unambiguous diagnosis wa made based on the biopsy; 11 % of the biopsies were not diagnostic. For the most part, toxoplasmosis (31%) and progressive multifocal leucoencephalopathy (29%) were involved. 18% of the patients suffered from a non-Hodgkin lymphoma. The foci were primarily frontal (47%), parietal (21%) or localised in the basal ganglia area (11%). The result of the biopsy led to a change in treatment for 52% of the patients. Morbidity and mortality of the operation were 0%.The results or our research series are similar to other groups. It was shown that stereotactic brain biopsy is a safe and effective method for establishing a sound basis for treating the frequently life-threatening cerebral complications of AIDS.  相似文献   
66.
Résumé  La rencontre entre patient et thérapeute dans la relation de soins met en présence non seulement deux individus, mais aussi deux systèmes de pensée. Elle suppose donc l'articulation de deux types de savoirs, profane d'une part et scientifique d'autre part. La clarification et la prise en compte des représentations du patient à propos de l'atteinte dont il souffre constitue un enjeu important de la relation. Il en va de même des attentes du thérapeute par rapport à ce qu'il considère comme un comportement douloureux adéquat, par exemple. Faute de la prise en compte des modèles de référence explicites et implicites tant du patient que du thérapeute, la relation peut déboucher sur des malentendus, des réactions d'agressivité, d'anxiété, et conduire à une rupture de cette relation.
Summary  The patient-therapist relationship involves not only two individuals, but also two systems of thinking. It calls forth lay knowledge on the one hand and scientific knowledge on the other hand. The patient's representations about his pain and suffering may play an important role in the patient-health care provider relationship and thus need to be clarified and taken into account. This need also holds true where the therapist's expectations are concerned, for example with regard to what is considered as an adequate pain behavior. Failing to take into account the explicit and implicit models of both the patient and the therapist may lead to misunderstandings, aggressive behaviors, anxious reactions, and thus hamper or even disrupt the patient-therapist relationship.
  相似文献   
67.
OBJECTIVE: Previous studies have identified age, renal failure and aneurysm extent as predictors of mortality following thoracoabdominal and descending thoracic aortic aneurysm (TAA) repair. We studied the impact of coronary artery disease (CAD) and cardiac function on 30-day mortality following TAA repair. METHODS: Between February 1991 and May 2001, we performed 854 TAA repairs. Two hundred ninety-one patients (34%) had a history of coronary artery disease. One hundred forty-one/291 (49%) had undergone coronary artery bypass surgery (CAB) prior to TAA repair. We conducted multivariable analyses of known risk factors along with the left ventricular ejection fraction (EF) and prior CAB to determine the adjusted effect of CAD on outcome. RESULTS: Mortality in patients with CAD was 54/291 (18%) compared to 75/563 (13%) without CAD (P<0.05). In patients who had prior CAB, mortality was 31/141 (22%) compared to 98/713 (14%) patients without prior CAB, (P<0.02). In multivariable analysis, the effects of CAD and CAB on mortality were eliminated by consideration of a low EF (defined as less than 50%). CONCLUSION: Impaired left ventricular function appears to be the strongest cardiac predictor of mortality for TAA repair, independent of the presence of coronary artery disease or coronary artery bypass revascularization.  相似文献   
68.
The metabolic fate of the benzodiazepine antagonist RO 15-1788 labelled with 11C was studied in plasma from human subjects after intravenous administration in connection with positron emission tomography. Ro 15–1788 and its metabolites were separated by thin-layer chromatography and the radioactivity in the different compounds was determined. 11C-Ro 15–1788 was extensively and rapidly metabolised to the corresponding free acid. At 36 minutes after administration only 50% of the radioactivity in plasma represented unchanged compound.  相似文献   
69.
70.
Successful internal arterial embolization with steel coils in life-threatening bleeding after femoral fracture is described in an older patient.  相似文献   
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