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81.
82.
A woman with a 50-year history of intense handwriting anxiety was treated wwith an in-vivo desensitization procedure. The technique was an adaptation of a method described by Janet in 1925. After only six sessions the subject was able to write in front of strangers without anxiety. Treatment effects were maintained at six month follow-up.  相似文献   
83.
Summary A 60-year-old woman affected by myasthenia gravis with onset at 27 years is described. At the age of 54 years the patient showed amyotrophy of the shoulders and of the legs with bilateral steppage. There was a gradual worsening and progression of the atrophy to other muscles. The nature of the disease is discussed following EMG and histologic data.
Zusammenfassung Es wird eine 60jährige Frau, die an Myasthenia gravis leidet, beschrieben. Die Krankheit begann, als sie 27 Jahre alt war. Mit 54 Jahren zeigte die Patientin eine Myatrophie der Schulter und der Beine mit bilateralem Steppengang. Zunehmende Verschlechterung und Übergreifen der Atrophie auf andere Muskelgebiete. Die Natur der Krankheit wird auf der Basis der EMG und der histologischen Befunde besprochen.
  相似文献   
84.
The authors describe a clinical case in which they found the unusual combination of acute hepatitis caused by HCV and pericarditis in a young person, resulting in complete recovery from the pericarditis but in a deterioration of the chronic HCV. A close examination of the literature on this subject revealed that, although no similar case was recorded, an aetiological relationship between the hepatitis C virus and pericarditis cannot be excluded since an HCV infection often gives rise to extra-hepatic cardiac problems.  相似文献   
85.
When the brain interacts with the environment it constantly adapts by representing the environment in a form that is called an internal model. The neurobiological basis for internal models is provided by the connectivity and the dynamical properties of neurons. Thus, the interactions between neural tissues and external devices provide a fundamental means for investigating the connectivity and dynamical properties of neural populations. We developed this idea, suggested in the 1980s by Valentino Braitenberg, for investigating and representing the dynamical behavior of neuronal populations in the brainstem of the lamprey. The brainstem was maintained in vitro and connected in a closed loop with two types of artificial device: (a) a simulated dynamical system and (b) a small mobile robot. In both cases, the device was controlled by recorded extracellular signals and its output was translated into electrical stimuli delivered to the neural system. The goal of the first study was to estimate the dynamical dimension of neural preparation in a single-input/single-output configuration. The dynamical dimension is the number of state variables that together with the applied input determine the output of a system. The results indicate that while this neural system has significant dynamical properties, its effective complexity, as established by the dynamical dimension, is rather moderate. In the second study, we considered a more specific situation, in which the same portion of the nervous system controls a robotic device in a two-input/two-output configuration. We fitted the input-output data from the neuro-robotic preparation to neural network models having different internal dynamics and we observed the generalization error of each model. Consistent with the first study, this second experiment showed that a simple recurrent dynamical model was able to capture the behavior of the hybrid system. This experimental and computational framework provides the means for investigating neural plasticity and internal representations in the context of brain-machine interfaces.  相似文献   
86.
BACKGROUND: Morning blood pressure (BP) peak may be a risk factor for cardiovascular disease. Whether morning BP should be a target of hypertension treatment is not known. We investigated the relationship between morning BP variations, carotid internal-medial thickness (CIMT), circulating inflammatory markers, and sympathetic activity in hypertensive patients with different patterns of morning BP increase at baseline and after antihypertensive treatment. METHODS: One hundred twenty-eight hypertensive patients with morning BP peak (MP+) were compared with 196 hypertensive patients without morning BP peak (MP-). All patients performed 24-h ambulatory BP monitoring, assessment of CIMT, circulating concentration of C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-18 (IL-18), and urinary catecholamines. RESULTS: Compared with MP- patients, MP+ patients had higher CIMT and urinary catecholamine output (P < .001), as well as CRP, IL-6, and IL-18 (P < .001). We randomly assigned 128 drug-naive MP+ patients to either metoprolol or carvedilol, two antihypertensive drugs with different effects on sympathetic activity. The primary outcome was change in CIMT and circulating inflammatory markers at 12 months. Morning BP decreased more among patients in the carvedilol group (P < .001), whereas clinic BP showed a similar decrease in both groups. The CIMT (P < .001), IL-6 (P < .001), IL-18 (P < .001), and CRP (P < .001) decreased more in the carvedilol group than in the metoprolol group. The CIMT regression was observed in 49% of patients in the carvedilol group and 18% of patients in the metoprolol group (P < .01). Reduction in CIMT was directly associated with changes in morning BP. CONCLUSIONS: Higher CIMT and circulating inflammatory markers coexist in hypertensive patients with morning BP peak, and might contribute to their increased cardiovascular risk. Carotid atherosclerosis can be prevented by control of morning BP.  相似文献   
87.
BACKGROUND: Transcranial Doppler monitoring shows a high prevalence of microemboli during carotid artery stenting (CAS); however, the occurrence of cerebrovascular symptoms (CVSs) does not seem to be related to the microembolic load. OBJECTIVE: To evaluate embolic and hemodynamic transcranial Doppler monitoring findings and their relationships with the occurrence of procedural CVSs. Patients Fifty-four patients who had carotid stenosis of more than 70% underwent a total of 57 CAS procedures during transcranial Doppler monitoring of mean blood flow velocity and microembolic signals in the middle cerebral artery. The occurrence of transient ischemic attack, transient monocular blindness, and stroke during the CAS procedure was considered CVSs. RESULTS: Nine (15.8%) of the 57 patients had CVSs during the procedure (ie, 6 patients with transient ischemic attack, 1 with transient monocular blindness, 1 with a minor stroke, and 1 with a major stroke). The mean blood flow velocity median values were statistically significantly lower (P < .001) in the group of 9 patients with CVSs (36 cm/s; interquartile range, 32.3-38.5) compared with the 48 without CVSs (48 cm/s; interquartile range, 41.5-52). The median number of isolated microembolic signals was similar in the 2 groups (72; interquartile range, 66-81 vs 75; interquartile range, 67-83.5). The median number of microembolic signal showers (clusters of too many signals to be counted separately in one cardiac cycle) presented a nonsignificant prevalence in the patients with CVSs (9; interquartile range, 7.5-11.2) compared with the ones without CVSs (8.2; interquartile range, 7-9). CONCLUSION: The low flow velocity in the middle cerebral artery may impair the clearance of the microembolic load and should be considered a precursor of CVSs during the CAS procedure.  相似文献   
88.
A patient with thymoma-associated neuromyotonia and voltage-gated potassium channel (Kv1.2 and Kv1.6) antibodies by immunoprecipitation and rat brain immunolabeling was treated successfully with immunoadsorption and cyclophosphamide. Curiously, glutamic acid decarboxylase antibodies, absent at onset, appeared later. Stiff-person syndrome was absent, but fast blink reflex recovery suggested enhanced brainstem excitability. The range of antibodies produced in thymoma-associated neuromyotonia is richer, and the timing of antibody appearance more complex, than previously suspected.  相似文献   
89.
INTRODUCTION: Insulin resistance, a novel cardiovascular risk factor, is often associated with increased plasminogen activator inhibitor-1 levels and impaired vasodilation. Insulin infusion in the forearm induces plasminogen activator inhibitor-1 and tissue plasminogen activator expression and endothelium-dependent vasodilation in normal subjects. The present study explores the relationship between insulin-induced vasodilatory and fibrinolytic properties of the endothelium in women with polycystic ovary syndrome, frequently affected by insulin resistance and early atherosclerosis. MATERIALS AND METHODS: Metabolic, hormonal and fibrinolytic parameters were evaluated in 64 patients with polycystic ovary syndrome (19 insulin-resistant and 45 insulin-sensitive) and in 25 controls. In 16 women with polycystic ovary syndrome, 8 insulin-resistant and 8 insulin-sensitive, blood flow, plasminogen activator inhibitor-1 and tissue plasminogen activator expression were evaluated during insulin infusion into the forearm. RESULTS: Elevated basal plasminogen activator inhibitor-1 levels were found in women with polycystic ovary syndrome, correlating directly with insulin levels. Plasminogen activator inhibitor-1 expression increased during insulin infusion in all women with polycystic ovary syndrome, but was delayed and sustained in insulin-resistant patients (p<0.01). Vasodilatory response to insulin was blunted (p<0.01) and tissue plasminogen activator expression abolished in insulin-resistant patients (p<0.01). CONCLUSION: Our study demonstrates that women with polycystic ovary syndrome and insulin resistance show a blunted endothelial-dependent vasodilation. The impaired endothelial release of tissue-plasminogen activator and the sustained plasminogen activator inhibitor-1 release during insulin infusion suggest a hypofibrinolytic state in PCOS patients with insulin resistance. This hemodynamic and fibrinolytic derangement may contribute to the pathogenesis of early atherosclerosis in insulin resistance.  相似文献   
90.
BACKGROUND AND PURPOSE: The relationship between location of occlusion and clinical outcome is poorly understood in patients receiving intravenous tissue-type plasminogen activator (IV tPA). We postulated that acute stroke patients receiving IV tPA with patent vasculature or occult arterial occlusion by CT angiography (CTA) would have better outcomes and decreased hemorrhagic risk. METHODS: We identified 47 patients from our prospective stroke database who underwent CTA before treatment with IV tPA. Site of occlusion was categorized as M1 segment of the middle cerebral artery, M2 segment, multiple (either carotid, basilar, or both middle and anterior cerebral arteries), or absent (no occlusion proximal to M3). The effect of site of occlusion on National Institutes of Health Stroke Scale (NIHSS), early improvement (> or = 4-point improvement in NIHSS at 24 hours after treatment), intracranial hemorrhages, and modified Rankin scale (mRS) at 7 days was tested in a multivariate analysis. RESULTS: The location of occlusion correlated with initial NIHSS for multiple, M1, M2 and absent occlusions (median NIHSS scores were 18, 18, 15, 10, respectively) (P < .02, rank sum). Following adjustment for initial NIHSS, age, and time to treatment, the absence of occlusion remained associated with early improvement (OR 5.0, 95% CI 1.1-23.3; P = .04) and independence at day 7 (mRS < or = 2) (OR 6.8, 95% CI 1.3-34.6; P = .02). Overall prevalence of symptomatic hemorrhages was 6.4%. Patients without occlusion had no hemorrhages (0% versus 23.3%; P < .04). CONCLUSION: Among patients treated with tPA, those with patent vasculature or occult distal occlusion on CTA before treatment have lower NIHSS, better chances of early improvement and early independence with fewer hemorrhages.  相似文献   
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