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61.
Cardiovascular malformations and organic solvent exposure during pregnancy in Finland 总被引:2,自引:0,他引:2
In order to investigate the possible association between cardiovascular malformations and maternal exposure to organic solvents during the first trimester of pregnancy, 569 cases and 1,052 controls were retrospectively studied. The cases represented all infants with diagnosed cardiovascular malformations born in Finland in 1982-1984, and the controls were randomly selected from all normal births in the country during the same period. All mothers were interviewed approximately 3 months after delivery by a midwife using a structured questionnaire. Exposures to organic solvents at work during the first trimester of pregnancy were slightly more prevalent among the mothers of affected infants (10.4%) than among those of controls (7.8%). Logistic regression analysis of exposure to organic solvents showed an adjusted relative odds ratio of 1.3 (95% confidence interval, 0.8-2.2). In the analysis of ventricular septal defect, exposure to organic solvents showed an adjusted relative odds ratio of 1.5 (95% confidence interval, 1.0-3.7). 相似文献
62.
用电子计算机对核素、多普勒和心尖搏动图中的8项左室舒张功能指标进行判别分析,比较各指标与冠心病的密切程度。结果显示患者年龄和各项舒张功能指标明显不同于正常组。判别方程为:Z=0.21X_1+23.86X_2-22.88X_3-0.18X_4+2.83X_5+2.06X_6+66.86X_7+1.66X_8。临界值为42.99。判别正确率为100%。各指标的贡献率大小依次为EV/AV,1/3FF,A/E-O,PFR,DATI,EDC,IRT和1/3FFd。提示:多普勒EV/AV与冠心病的关系最为密切,核素的1/3FF次之,心尖搏动图的A/E~O亦是一个较好的指标。 相似文献
63.
Suppiah Balachandran Stuart Eason Lynn McGuire Suzanne Bernard Charles Boyd 《European journal of nuclear medicine and molecular imaging》1986,12(2):69-71
Summary In order to measure ejection fractions (EFs) from nuclear ventriculograms, we devised a semi-automated edge-detection technique based on a combination of inverse Fourier analysis and second-derivative techniques. Initial clinical studies showed that, for the left ventricle, our method gives EF values statistically identical with those obtained using a conventional isocontour technique. For the right ventricle, however, the values obtained using the two methods were somewhat more at variance. Despite requiring a longer processing time, the results obtained with our method are reproducible because less operator intervention is necessary. 相似文献
64.
高血压患者左室构型和房性心律失常的关系 总被引:4,自引:0,他引:4
目的了解高血压患者左室构型和房性心律失常关系。方法应用超声心动图及动态心电图,测定左室结构及房性心律失常发生率。结果Kleiger3~6发生和构型有联系(P<0.001)。结论左室构型影响房性心律失常。 相似文献
65.
通过20例有左室肥厚和23例无左室肥厚患者发生急性心肌梗塞时CPK值的比较,发现在梗塞部位相同的情况下,心肌肥厚组的酶值水平高于非心肌肥厚组(13.2±4.8比9.0±4.6U/LP<0.01),这可能与肥厚组酶活力增强和心肌梗塞体积增大有关。 相似文献
66.
Ajit K. Shah Richard C. Brundage Kathleen D. Lake Ronald J. Sawchuk 《Biopharmaceutics & drug disposition》1995,16(1):59-70
We estimated the free fraction (fu) of cyclosporine (CyA) in the plasma from concentrations of CyA in urine (Cu) and plasma (Cp), urine flow rate (UF), and glomerular filtration rate in rabbits and in heart transplant patients. Following intravenous administration of CyA (5–30 mg kg?1) in ten NZW rabbits and oral administration of CyA (4.8–12.1 mg kg?1) in nine heart transplant patients, CyA concentrations in urine and plasma were measured by HPLC. The ratios of Cu to Cp and UF data were fitted to a physiological model of renal clearance using NONMEM. The free fraction of cyclosporine in the rabbits and the heart transplant patients was 0.0122 and 0.14, respectively. Because of the relatively low permeability of CyA across the tubular epithelium, no apparent equilibrium between Cu and Cp at any urine flow rate was reached and, therefore, the Cu to Cp ratio will not be equal to fu. 相似文献
67.
An immunohistochemical study of melanocytic tumours using 19A2, a monoclonal antibody against proliferating cell nuclear antigen (PCNA/cyclin), was performed on tissues routinely processed with formalin fixation and paraffin embedding. In normal skin, keratinocytes of the suprabasal region in epidermis, the papillae and outer root sheath of hair follicles and the basal cells lining the lobules of sebaceous glands were stained in the nucleus. Other skin components, including basal and follicular melanocytes, did not demonstrate nuclear labelling. In addition, expression of PCNA/cyclin in keratinocytes was higher in sun-exposed skin compared with unexposed skin. In melanocytic lesions, PCNA/cyclin positive tumour cells increased in number and staining intensity according to the following progression: common melanocytic naevi; dysplastic naevi; primary melanomas; and metastatic melanomas. Expression of PCNA/cyclin, therefore, provides a useful marker for proliferation and tumour progression in skin. 相似文献
68.
Tadashi Nakazawa Yoshiyuki Takami Robert Benkowski Satoshi Ohtsubo Ohashi Yukio Eiki Tayama Goro Ohtsuka Yoshinari Niimi Julie Glueck Akinori Sueoka Helmut Schmallegger Heinrich Schima Ernst Wolner Yukihiko Nosé 《Artificial organs》1997,21(7):597-601
Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device. 相似文献
69.
KEIJU KOTOH KOJI ISHII YOSHINOBU ABE PHILLIP DELEUZE DANIEL LOISANCE 《Artificial organs》1994,18(12):918-922
Abstract: Right ventricular (RV) failure during the use of a left ventricular assist device (LVAD) is the leading cause of death in circulatory support patients. Previous work, both experimentally and clinically, has shown the difficulties in predicting the behavior of the right ventricle at the start of LVAD. An experimental study has been designed to evaluate RV functional changes during LVAD and its relation to preload changes. The model used adult mongrel pigs (n = 10). Right ventricular functional parameters were measured with a thermodilution RV ejection fraction catheter. The left ventricle was supported by a Nippon Zeon blood pump. Two groups were studied, the first one was the LVAD–off group (n = 5) and the other was the LVAD–on group (n = 5) which was supported by LVAD at maximum flow. Change of cardiac output, mean pulmonary artery pressure (PAP), RV stroke work, and RV ejection fraction in both groups were not significantly different. However, the relationship between right ventricular end–diastolic pressure (RV–EDP) and right ventricular stroke volume (RVSV) was significantly changed at a high level of RV–EDP. When RV–EDP was over 6. 5 mm Hg in the LVAD–off group, RVSV decreased to 52. 3 ± 11. 5 ml while in the LVAD–on group, RVSV increased to 97. 2 ± 22. 0 ml. The change in PAP in the LVAD–on group was lower than in the LVAD–off group. We conclude that, at the volume overload state, LVAD can reduce the afterload of the right ventricle and maintain Frank–Starling's effect, thus having a beneficial effect on right ventricular performance. 相似文献
70.
BERND-DIETER GONSKA KEJIANG CAO ANSELM SCHAUMANN AXEL DORSZEWSKI FRIEDERIKE von zur MÜHLEN HEINRICH KREUZER 《Pacing and clinical electrophysiology : PACE》1994,17(3):542-549
The management of patients after catheter ablation of ventricular tachycardia is not well defined. In this article we summarize recently published results and report our own experience. Factors influencing the clinical outcome of these patients and methods to identify patients with an increased risk of recurrence of ventricular tachycardia are discussed. Furthermore, a review is given on current concomitant therapeutic tools including antiarrhythmic drugs and the implantation of an automatic cardioverter defibrillator. 相似文献