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1.
To clarify the risk-benefit ratio involved in association of antiarrhythmic drugs, a combined therapy of amiodarone and propafenone was tested by means of continuous electrocardiographic monitoring, analysis of levels of the drug in the plasma and programmed electrical stimulation in a selected group of 10 patients who had left ventricular dysfunction and spontaneous relapses of sustained ventricular tachycardia despite treatment with amiodarone. Induction of sustained ventricular tachycardia, possible in each case during treatment with amiodarone, was suppressed after addition of propafenone in 2 patients (responders), who had the best ejection fractions of the entire group (greater than 45%). Worsening of spontaneous tachycardias developed in 4 cases during the combined therapy. These ventricular arrhythmias, although generally at a low rate, sometimes had the potential to degenerate into ventricular fibrillation and disappeared after both discontinuation of propafenone or increase of its dosage (1 patient). Of the six cases undergoing chronic combined treatment, only the responders to premature electrical stimulation were completely protected from recurrences of arrhythmia. Three cases, on the other hand, needed permanent endocardial pacing for symptomatic bradyarrhythmias. The combination of treatment with amiodarone and propafenone, although potentially useful in limiting dosages of and toxicity from amiodarone, is frequently associated with undesirable, and occasionally has severe, side-effects. The best candidates for this pharmacological association seem to be patients without severely depressed left ventricular function who have a greater probability of not presenting the inducibility of ventricular tachycardia after the addition of propafenone to the regimen for treatment.  相似文献   
2.
An epidemiological retrospective survey on primary pulmonary hypertension was undertaken in Italy in 1985-6. The aim of the study was to obtain clinical and laboratory data on patients observed in the major cardiological Institutions, both Universities and Hospital Clinical Centers, in the period 1975-85. Forms were sent to 67 centers and twenty-three of them communicated their data on 124 cases of primary pulmonary hypertension. The diagnosis was considered certain or probable in 91 patients by the referring center. The mean age of patients was 38.5 years, with an overall female-to-male ratio of 2:1. Data were subjected to statistical analysis which confirmed the poor prognosis of the disease particularly for patients with high pulmonary resistances, low cardiac output and in class 3-4 of the NYHA. Half of the 124 cases were treated with calcium antagonists after 1980, but the results of therapy in modifying the clinical course of the disease could not be assessed by the study. Like all retrospective studies even the Italian Multicenter Study is biased but it can be considered as an useful preliminary investigation which can form the basis for a prospective registry of primary pulmonary hypertension cases.  相似文献   
3.
X-linked dilated cardiomyopathy (XLDC) is a familial heart disease presenting in young males as a rapidly progressive congestive heart failure, without clinical signs of skeletal myopathy. This condition has recently been linked to the dystrophin gene in some families and deletions encompassing the genomic region coding for the first muscle exon have been detected. In order to identify the defect responsible for this disease at the molecular level and to understand the reasons for the selective heart involvement, a family with a severe form of XLDC was studied. In the affected members, no deletions of the dystrophin gene were observed. Analysis of the muscle promoter, first exon and intron regions revealed the presence of a single point mutation at the first exon-intron boundary, inactivating the universally conserved 5' splice site consensus sequence of the first intron. This mutation introduced a new restriction site for MseI, which cosegregates with the disease in the analyzed family. Expression of the major dystrophin mRNA isoforms (from the muscle-, brain- and Purkinje cell-promoters) was completely abolished in the myocardium, while the brain- and Purkinje cell- (but not the muscle-) isoforms were detectable in the skeletal muscle. Immunocytochemical studies with anti- dystrophin antibodies showed that the protein was reduced in quantity but normally distributed in the skeletal muscle, while it was undetectable in the cardiac muscle. These findings indicate that expression of the muscle dystrophin isoform is critical for myocardial function and suggest that selective heart involvement in dystrophin- linked dilated cardiomyopathy is related to the absence, in the heart, of a compensatory expression of dystrophin from alternative promoters.   相似文献   
4.
Intravenous injection of platelet-activating factor (PAF) (0.36 mol/kg b.w.) in mice induced severe hemoconcentration, leucopenia, thrombocytopenia and finally the death of 85% of the tested animals. Combined inhibition of histamine and serotonin by promethazine and chlorpromazine, 6.24 and 3.12 mg/kg b.w. subcutaneously, protected the mice from PAF in part, reducing the death rate to 43%. These drugs did not protect the mice against the PAF-induced hemoconcentration, leucopenia and thrombocytopenia. Sulfinpyrazone (100 mg/kg b.w.) intravenously was the most effective both in protecting mice from PAF-induced death, reducing the death rate to 17%, and from thrombocytopenia, although hemoconcentration persisted. These results indicated that an important component of the PAF-induced systemic effects is mediated by reactions which can be inhibited by sulfinpyrazone. Furthermore, PAF-induced thrombocytopenia is not a direct PAF effect since it can be inhibited by sulfinpyrazone.  相似文献   
5.
OBJECTIVES: To assess, in women participating in a breast cancer prevention trialon fenretinide (4-HPR), the relationship of drug and retinol levels with the risk of second breast malignancy, taking into account age and menopausal status. METHODS: In a multicenter prevention trial, women with early breast cancer were randomly assigned to receive no treatment or 200 mg of 4-HPR/day for 5 years. Blood was collected at baseline and on a yearly basis during intervention from women recruited at the Istituto Tumori (Milan, Italy; 818 and 756 in the 4-HPR and control arm, respectively, who accounted for 53% of the participants in the trial). The plasma concentrations of 4-HPR, its main metabolite N-(4-methoxyphenyl) retinamide, and retinol were assayed by high-performance liquid chromatography. Three age ranges (or=56 years), menopausal status at baseline, and disease outcome at a median follow-up of 97 months were taken into account in the analysis. RESULTS: Baseline retinol levels were significantly lower (P or=46 years versus or= 0.71; P 相似文献   
6.
The aim of this study was to assess the prognostic role of soluble interleukin-2 receptors (sIL-2R) in Hodgkin''s disease (HD) both in the achievement of complete remission (CR) and in predicting disease relapse. Between August 1988 and June 1993 sIL-2R serum levels were measured in 174 untreated patients; in 137 of them evaluation was repeated at the end of treatment and in 132 also during the follow-up. Baseline sIL-2R levels (mean+/-standard error) were significantly higher in patients than in 65 healthy control subjects (1842+/-129 U ml(-1) vs 420+/-10 U ml(-10, P< 0.0001). At the end of treatment 135 out of 137 evaluated patients achieved complete response (CR) and their mean sIL-2R serum levels were significantly lower than those at diagnosis (635+/-19 U ml(-1) vs 1795+/-122 U ml(-1), P=0.0001). After a median follow-up of 5 years, sIL-2R remained low in 114 patients in continuous CR, while they increased in 9 out of 12 patients (75%) who relapsed. However, a temporary increase was also observed in six patients (5%) still in CR. Treatment outcome in terms of freedom from progression was linearly related to sIL-2R levels. Our study confirms that patients with untreated HD have increased baseline levels of sIL-2R compared with healthy subjects and that their pretreatment values may be an indication of disease outcome similar to other conventional prognostic factors, such as number of involved sites, presence of B symptoms and extranodal extent.  相似文献   
7.
In 183 consecutive patients with recent, uncomplicated myocardial infarction, the following variables were associated with 4-year cardiac death: haemodynamic decompensation with exercise (P = 0.01), left ventricular ejection fraction at rest (P = 0.004) and at peak exercise (P = 0.003), persistent ST segment elevation at rest in the area of infarction = (P = 0.004), exercise-induced ST segment elevation (P = 0.02), and late aneurysmal evolution (P = 0.01). Exercise left ventricular ejection fraction was the sole variable selected by Cox regression analysis as an independent predictor of cardiac death. In 40 patients with ST segment elevation at rest, left ventricular ejection fraction was 42 +/- 17% at rest and 40 +/- 18% at peak exercise, versus 52 +/- 12% and 52 +/- 14% in the remaining patients (both P less than 0.01). Among these 40, 16 (all with anterior infarction) also had exercise-induced ST segment elevation; their ejection fraction was 32 +/- 13% at rest, 30 +/- 13% during exercise, versus 53 +/- 15% and 53 +/- 15% in 129 patients with no ST segment elevation either at rest, or during exercise (both P less than 0.01). The 4-year risk of death was 20% in the former 40 patients, 36% in the latter 16, while in the complete absence of ST segment elevation, such risk was 3%. All 14 patients with ST segment elevation only during exercise were alive after 4 years: their left ventricular ejection fraction was 47 +/- 12% at rest, 45 +/- 13% with exercise. ST segment elevation was associated with late aneurysmal evolution but not with exercise-induced ischaemia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Transluminal angioplasty was performed as an urgent treatment in 9 patients with unstable angina, refractory to medical therapy and ST elevation during pain. All had a coronary stenosis greater than 50% (89 +/- 12%; range 60-99%). The left anterior descending coronary artery was affected in 6 patients, the right coronary artery in 1 patient, the circumflex in 1 patient and 1 patient had two stenosis on both the left anterior descending and the first diagonal branch. A reduction of the luminal stenosis greater than 20% was obtained in all (residual stenosis 30 +/- 11%; range 11-40%). During a follow-up of 6-20 months, two patients only showed recurrence of chest pain. A maximal ergometric test was negative in all patients after 1, 3 and 6 months. A second arteriography, performed in 7 patients after 3-6 months, demonstrated a mean stenosis of 35% (range 30-40%). Transluminal coronary angioplasty is a feasible and effective therapeutic approach in patients with unstable angina and ST elevation, when a significant coronary stenosis is present.  相似文献   
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