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81.
Raised levels of serum immunoglobulin E are found in many parasitic diseases. In order to determine the influence of Giardia lamblia on IgE levels of clinically symptomatic patients, a controlled study was performed. There was no difference between the serum IgE values from Brazilian patients with giardiasis and those from normal Brazilian controls, although in both groups there were many individuals with values higher than the normal range reported from the northern hemisphere.  相似文献   
82.
Studies in man demonstrated that intramuscular salmon (s) calcitonin (CT) administration blunted pituitary GH response to hypothalamic stimuli such as arginine infusion and insulin-induced hypoglycaemia. However, the mechanisms underlying this inhibiting action of CT are still unclear. The aim of our study was to investigate the effects of intranasal (i.n.) and i.m. sCT administration on GH secretion elicited by direct pituitary stimulation in man with human GH-releasing hormone (GHRH) (1-29)NH2. Seven healthy non-obese volunteers (five men, two women; mean age +/- SDM 25 +/- 2) underwent a bolus intravenous injection of GHRH, 100 micrograms, alone or associated with sCT, administered either i.n., 300 IU, or i.m., 100 IU. Our data demonstrate a significant decrease in GH secretion after GHRH when either i.n. or i.m. sCT is administered. GH peak (mean +/- SDM); GHRH alone 22.9 +/- 2.5 vs GHRH plus i.n. sCT, 8.9 +/- 1.5 micrograms/l, P less than 0.001; or vs GHRH plus i.m. sCT 12.3 +/- 2.5 micrograms/l, P less than 0.001. Area under the curve of GH secretion: GHRH alone 1211 +/- 196 vs GHRH plus i.n. sCT 551 +/- 116 micrograms 120 min/l. P less than 0.001; or vs GHRH plus i.m. sCT 700 +/- 167 micrograms 120 min/l, P less than 0.001. We conclude that sCT is able to inhibit GHRH-stimulated GH secretion in man.  相似文献   
83.
BIFFI, M., et al .: Abnormal Cardiac Innervation in Patients with Idiopathic Ventricular Fibrillation. Idiopathic ventricular fibrillation (VF) is diagnosed in up to nearly 10% of survivors of out-of-hospital cardiac arrest. The arrhythmogenic substrate is unknown. This study examined the role of cardiac innervation as a possible contributor to this arrhythmia. Eight patients with idiopathic VF were compared with eight normal subjects (controls) by [123] I metaiodobenzylguanidine SPECT (MIBG), measuring peak uptake, late uptake, and clearance of the nuclear tracer. The left ventricle was divided in 13 segments in the bull's-eye target plot. Peak and late MIBG uptake was increased in the anterolateral segments (2,3,7,8) compared to the inferoposterior and septal segments, in controls and in patients. No difference was observed between controls and patients in the inferoposterior and septal segments. In contrast, a significantly higher MIBG uptake was observed in patients compared to controls in the anterolateral segments (   94 ± 4%   vs   81 ± 11%, P < 0.03   for peak uptake;   94 ± 5%   vs   79 ± 12%, P < 0.01   for late uptake). No difference was observed in MIBG clearance in any segment in either study group. Cardiac sympathetic innervation is highly heterogeneous, though predominant in anterolateral segments in normal subjects. Patients with idiopathic VF exhibit the same distribution, though have a significantly greater density of sympathetic terminals in the anterolateral segments than controls, which may promote ventricular arrhythmias. (PACE 2003; 26[Pt. II]:357–360)  相似文献   
84.
In a population of 417 hospitalized patients, the efficacy and safety of different drug regimens administered to convert atrial fibrillation (AF) of recent anset (≤ 7 days duration) to sinus rhythm were evaluated. All patients were in NYHA Class ≤ 2, and free of heart failure. They were randomly allocated to treatment with placebo in 121 patients; IV amiodarone, 5 mg/kg bolus, followed by 1.8 g/24 hours in 51 patients; IV propafenone, 2 mg/kg bolus, followed by 0.0078 mg/kg/min in 57 patients; p.o. propafenone, 600 mg p.o. in a single dose in 119 patients; and p.o. flecainide, 300 mg p.o. in a single dose in 69 patients. All patients were continuously monitored by Holter ECG, and the number of conversions to sinus rhythm was measured at 1, 3, and 8 hours. Results: (1) IV propafenone resulted in a higher conversion rate within 1 hour compared with the oral loading regimens of propafenone or flecainide, but the conversion rates at 3 and 8 hours were comparable, approximately 75% at 8 hours; 2) IV amiodarone was not different from placebo until 8 hours when it was associated with 57% of conversions; (3) conversion to sinus rhythm at 8 hours was observed in 37% of the placebo treated patients. Serious adverse effects occurred in few patients: two patients treated with flecainide and one treated with IV propafenone experienced left ventricular decompensation; one patient treated with placebo and two treated with flecainide had atrial flutter with rapid ventricular response. In conclusion, single-dose, oral loading with propafenone or flecainide are acceptable alternatives to conventional drug regimens in selected hospitalized patients. In addition, the measure of a placebo effect is mandatory in studies of recent-onset AF.  相似文献   
85.
The rejection of interferon alpha1 gene-transfected mammary adenocarcinoma cells (TSA-IFNα) injected into syngeneic BALB/c mice was accompanied by an unusual stromal reaction and marked CD8-positive T-lymphocyte involvement. To investigate the biological background of this reaction, the possibility was evaluated that an interaction between TSA-IFNα and stromal cells might remodel the extracellular matrix (EM). When fibroblasts were co-cultured with TSA-IFNα or treated with exogenous IFNα, there was no change in their replication rate or collagen synthesis. By contrast, their fibronectin (FN) production and release were increased, resulting in enhanced fibroblast chemotaxis. These findings were mirrored by increased FN staining in the peritumoural and tumoural areas in vivo. IFNα thus determines increased FN production and hence massive local recruitment and activation of fibroblasts, with a modification of the EM. The several activities of IFNα should thus be considered prior to its employment in clinical trials. © 1997 by John Wiley & Sons, Ltd.  相似文献   
86.
87.
Background: Large patent foramen ovale (PFO), spontaneous right‐to‐left shunt, large atrial septal aneurysm (ASA), coagulation abnormalities, and prominent eustachian valve (EV) have all been independently suggested as risk factors for recurrent stroke. We sought to retrospectively evaluate risk of stroke and impact of transcatheter PFO closure in patients with concurrent large PFO, spontaneous right‐to‐left shunt, large ASA, coagulation abnormalities, and prominent EV. Methods: Between March 2006 and October 2008, 36 (mean age 44 ± 10.9 years, 28 females) out of 120 consecutive patients referred to our center for transcatheter PFO closure had concomitant diagnosis of (a) large PFO on transcranial Doppler (TCD) and transesophageal echocardiography (TEE), (b) spontaneous right‐to‐left shunt on TCD, (c) large ASA, (d) prominent EV, and (e) coagulation abnormalities. All patients fulfilled the standard current indications for transcatheter closure and underwent preoperative TEE and brain magnetic resonance imaging (MRI), with subsequent intracardiac echocardiographic‐guided transcatheter PFO closure. Results: Compared to the remaining PFO population in the same period, patients with all five concomitant features had more ischemic brain lesions on MRI, previous history of recurrent stroke, more frequently a history of venous thromboembolism, and more severe migraine with aura. The concomitance of all the features confers the highest risk of recurrent stroke (OR 9.9, 3.0–18 [95% CI], P < 0.001). Conclusions: Despite its small sample size and nonrandomized retrospective nature, this is the first study to suggest that patients with concurrence of all the investigated characteristics have potentially a higher risk of stroke compared to controls. We thus propose the CARP criteria as a basis for further larger, longitudinal studies to assess the potential benefits of transcatheter closure in this patient subset in the absence of clinical recurrent stroke.  相似文献   
88.
89.
All-Ceramic Post, Core, and Crown: Technique and Case Report   总被引:1,自引:0,他引:1  
The functional and esthetic restoration of severely compromised anterior teeth is a challenge to clinicians in their daily practice. The duplication of the optical characteristics of an intact tooth, including shade, translucency, and fluorescence, is often made difficult by the use of metal infrastructures, such as post-and-cores and copings. The development of reinforced ceramics and non-metallic post systems made possible the generation of metal-free ceramic restorations in severely compromised anterior and posterior teeth. This article discusses one available technique for the generation of a single all-ceramic restoration involving the use of a zirconia- or leucite-reinforced post-and-core system and of an all-ceramic crown system. A representative clinical case is presented illustrating the potential of the technique.  相似文献   
90.
The aim of this study was to evaluate the efficacy of low energy internal atrial cardioversion in restoring sinus rhythm (SR) in patients with chronic atrial fibrillation (AF) persisting > 1 year. Fifteen patients with chronic AF lasting > 1 year (from 13–48 months, mean 24 ± 13 months) were studied. R wave synchronized 3/3 ms biphasic shocks were delivered between right atrial and coronary sinus (left pulmonary artery in five patients) electrodes. Sedatives or anesthetics were administered only at the patient's request. Results: Stable SR was restored in 14 (93%)of 15 patients after shocks with a mean leading edge voltage of 377 ± 77 V (range 260–500) and a mean delivered energy of 7.3 ± 3.4 J (range 2.6–12.9). The procedure was performed without anesthesia in 6 (40%) patients. All successfully cardioverted patients were treated with flecainide, sotalol, or amiodarone. During a follow up of 7.7 ± 7.9 months (range 1–24) AF recurred in five (36%) patients. Three of five AF recurrences occurred within 3 days after conversion to SR. Conclusion: Internal low energy atrial cardioversion is highly effective in restoring SR even in patients with AF lasting > 1 year. The long-term results from the standpoint of freedom from AF recurrences, are satisfactory, although additional antiarrhythmic treatment is required, particularly in the first days after conversion.  相似文献   
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