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81.
To evaluate the existence, timing, and determinants of post-infarction left atrial remodeling, we studied a subgroup of 514 patients from the Third Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico Echo Substudy who underwent 4 serial 2-dimensional echocardiograms up to 6 months after acute myocardial infarction. This study is the first to demonstrate, in a large series of patients, the existence of early and late left atrial remodeling after low-risk acute myocardial infarction and the relation of left atrial remodeling to left ventricular remodeling.  相似文献   
82.
83.
In order to assess the reliability of Doppler echocardiography in the determination of mean mitral gradient 38 consecutive patients (pts) affected by rheumatic mitral valve stenosis (MS) were analyzed by continuous wave Doppler echocardiography (CWD). Cardiac catheterization (CATH) was performed within 24 hours from echocardiographic examination. The mean diastolic mitral gradient (MG) at CATH was calculated by planimetry from simultaneously recorded left ventricular and pulmonary artery wedge pressure. The maximal velocity profile through the mitral valve was used to calculate pressure gradient by CWD. A mean mitral gradient was calculated for each patient by the planimetered velocity profile throughout diastole. MG determined by CATH ranged from 6 to 31 mmHg (mean 15.2 +/- 6.0); MG determined by CWD ranged from 4 to 18 mmHg (mean 10 +/- 3.7). The correlation between CWD and CATH by linear regression analysis was: y = 0.53 X + 1.8; r = 0.85; p less than 0.001. Mean % error of CWD in the assessment of MG was 34.7%. In conclusion this study indicates that CWD seems systematically underestimate MG with respect to CATH. The identification of CWD flow tracings "optimal" for analysis could not represent the maximal velocity of transmitral jet, which is a complex three dimensional entity. In addition non-simultaneous determinations of gradient and day-to-day variations in cardiac output may account for discrepancies between CWD and CATH measurements.  相似文献   
84.
Wolf  GL 《Radiology》1986,159(2):557-558
The advantages of the new, safer, but more expensive iodinated contrast agents are discussed, and opinions on which patient groups should receive the agents are presented.  相似文献   
85.
用Harris冠脉结扎法诱发的心律失常狗研究常咯啉药代动力学-药效动力学。7只狗按83.33μg·kg-1·min-1静脉滴注60min,在给药期间和停药后不同时间记录ECG及测定血药浓度。C-T数据用药代程序计算药代参数;药效数据用药代-药效同步分析模型计算药效动力学参数,K10, T1/2,Vd,Cl分别为0.0087min-1,78.03min,40.55ml·kg-1和0.421ml·kg-1·min-1;KeOCe(50)分别为0.0048min-1和2.01μg·ml-1.  相似文献   
86.
87.
The authors present a case of an adenoma of the nipple in a 61-year-old man who reported a 6-month history of nodularity and itching at his left nipple. Examination revealed a firm, well-defined, vascularized tumor measuring .8 cm that altered the normal anatomy of the nipple. A total excision of the nipple and areola was performed. The histological diagnosis was adenoma of the nipple. No recurrent tumor has been observed during 4 years of postoperative follow-up. An adequate excision of the lesion is curative without any risk of recurrence or development of malignancy.  相似文献   
88.
OBJECTIVE: To monitor and describe the time trends of the HIV epidemic among intravenous drug users (IDU) attending drug dependence treatment centres (DDTC) in Northern Italy. DESIGN: A cohort of all seronegative IDU attending DDTC in Lombardy between 1993 and 1999; all had been tested for HIV at least twice. Periodic sample interview surveys were done to assess risk behaviours. METHODS: The incidence rates of HIV infection were calculated using the person-year (PY) method and expressed as the number of cases per 1000 PY at risk. Background HIV prevalence was calculated by dividing the number of positive cases by the total number of IDU tested at all DDTC in Lombardy. RESULTS: Between 1993 and 1999, 135 seroconversions occurred in 7945 subjects followed for 19 671 PY, yielding an incidence rate of 6.9/1000 PY. Ninety seroconversions occurred among the 6563 males and 45 seroconversions among 1382 females (incidence rates 5.5 and 14.0, respectively). Among the males, the incidence of HIV was 4.5 in those aged less than 25 years and 5.8 in those aged 25 years or more. Among the females, the corresponding figures were 21.1 and 10.3. HIV prevalence decreased over time, and it was higher among females. Sexual behaviours at risk were more common among females. CONCLUSIONS: The incidence of HIV infection among IDU in Northern Italy was stable between 1993 and 1999. The higher incidence and prevalence among females and the different prevalence of risk behaviours between genders suggest an increasing role of heterosexual transmission.  相似文献   
89.
Focal hand dystonia in a patient with thoracic outlet syndrome   总被引:1,自引:0,他引:1       下载免费PDF全文
A patient affected by thoracic outlet syndrome, with aninvolvement of the left lower primary trunk due to a rudimentarycervical rib, developed a severe hand dystonia on the same side. Thedystonic posture was characterised by a flexion of the wrist with thefingers curled into the palm. Polygraphic recordings performed on the left flexor digitorum superficialis (FDS4) and extensor digitorum superficialis (EDC4) muscles, during a repetitive tapping task of thefourth digit, showed a loss of well formed bursts without a clearsilent period along with long duration bursts of cocontraction inantagonistic muscles. The study of reciprocal inhibition between forearm flexor and extensor muscles showed a reduced amount of inhibition in both the disynaptic and the later presynaptic phase ofinhibition. The patient underwent an operation with resection of thecervical rib. Twelve hours after the operation the patient experienceda significant improvement of the hand dystonia; the distonia haddisappeared completely by two months with a progressive normalisationof reciprocal inhibition.

  相似文献   
90.
We measured plasma corticotropin-releasing hormone (CRH), ACTH, beta-endorphin (beta-EP), and cortisol levels as possible tumor markers in a sequence of 103, randomly selected, patients with lung cancer but without the ectopic Cushing's syndrome and in 72 age- and sex-matched controls. Plasma CRH levels of cancer patients were similar to those of controls both in patients sampled in the morning or in the afternoon. On the other hand, plasma ACTH levels of cancer patients were significantly higher than control patients both in the morning and in the afternoon and showed a preserved circadian rhythm. However, about 35% of cancer patients sampled in the morning and about 60% of those sampled in the afternoon had ACTH levels within the 95% confidence interval (CI) of controls. Also plasma beta-EP levels were more elevated in cancer patients than controls in the morning but about 33% of them and about 80% of those sampled in the afternoon had beta-EP levels within the 95% CI of controls. Despite the higher plasma ACTH levels, cancer patients had cortisol plasma levels similar to controls with preserved circadian rhythm. In conclusion, although mean plasma ACTH and beta-EP were higher in patients affected by lung cancer, their measurements, as well as those of CRH, have practically no diagnostic value. Perhaps measurement of ACTH levels in the bronchial lavage may be more helpful.  相似文献   
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