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OBJECTIVE: Autonomic modulation of hemodynamics, essential for the preservation of homeostasis, is well tested by the abrupt postural change from clinostatism to active orthostatism. The aim of this work was to study normal relationships between the cardiovascular variables in active orthostatism and those in clinostatism. METHODS: Hemodynamic parameters in clinostatism and orthostatism were easily measured in 20 healthy subjects of both sexes, aged between 33 and 78 years, without treatment, using the non-invasive thoracic electric bioimpedance method. RESULTS: Cardiovascular variables values in orthostatism are linearly related with their values in clinostatism. CONCLUSIONS: Results show that cardiovascular variables in active orthostatism are linearly related with their values in clinostatism, each variable being specially regulated. A clinostatism and orthostatism intraindividual correlation was obtained, which provides an easily accessible method of detection and interpretation of autonomic dysfunctions, without deleterious consequences for the subjects, which can be very useful for research on physiopathologic mechanisms.  相似文献   
63.
It is conceivable that the subjects who have phonatory disorders, in comparison with normal individuals, exert a greater expiratory effort when phonating loudly. Furthermore, we presume that the extent and pattern of the changes in the expiratory effort for increasing vocal intensity may vary according to the types of laryngeal lesions. To prove these hypotheses, we investigated the changes in expiratory effort for increments of the vocal intensity by measuring the expiratory lung pressure. The subjects included 10 each of normal controls, patients with Reinke's edema, and those with recurrent laryngeal nerve paralysis. For the normal controls, the increase in vocal intensity was achieved by slightly increasing the expiratory lung pressure. The patients with Reinke's edema showed a greater increase in expiratory lung pressure, as compared with the normal group. The patients with recurrent laryngeal nerve paralysis exhibited greater expiratory effort with extreme increases in airflow than normal group for louder phonation. It was concluded that the subjects who have phonatory disorders, in comparison with normal individuals, require a greater expiratory effort. This phonatory function test with an increase in voice intensity made the aerodynamic pathologic condition clearer.  相似文献   
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This study replicates preliminary findings reporting a quantitative electroencephalographic (QEEG) profile of crack cocaine dependence in abstinence. All subjects (n = 52) met criteria for DMS-III-R cocaine dependence (in the form of crack), and were residing in a drug-free therapeutic community. Baseline QEEG evaluations were conducted at intake (5-10 days after last use of crack, and at follow-up (1 month after last reported use). Previous findings of significant excess of relative alpha power and deficit of absolute and relative delta and theta power were replicated in this expanded group. Abnormalities were greater in anterior than posterior regions, and disturbances in interhemispheric relationships were also observed. Further, QEEG showed little change in the interval between the first and second evaluations. This QEEG profile may reflect persistent alterations in neurotransmission as a possible consequence of chronic cocaine exposure.  相似文献   
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The reliability of helical CT as sole preoperative diagnostic technique for abdominal aortic aneurysms (AAA) and its accuracy in detecting vascular anomalies in the abdominal region was evaluated retrospectively in 42 patients with asymptomatic AAA > 40 mm. A single breath-holding helical scan was performed with 5 mm slice thickness, during a single injection of contrast medium, resulting in a 20 cm z-axis coverage. Axial images were reconstructed and used to generate high quality multiplanar reformatted images. Digital subtraction angiography (DSA) was performed in the first 18 patients and then in case of associated peripheral vascular disease (6 patients). Helical CT exactly showed, in all cases, the proximal and distal extent of the AAA. The visceral vessels as well as the inferior vena cava and renal veins were always clearly depicted, showing anatomical variants or pathological involvement in 19 patients. DSA gave sufficient details on the distal run-off but did not allow a reliable visualization of the visceral branches, venous anomalies and true extent of AAA. In our experience helical CT should be considered as the sole method for preoperative imaging of AAA. It allows a complete and precise evaluation; it is fast, with low doses of radiations and does not require hospitalization.  相似文献   
68.
The utility of modified vaccinia virus Ankara (MVA) as a vector for eliciting AIDS virus-specific cytotoxic T lymphocytes (CTL) was explored in the simian immunodeficiency virus (SIV)/rhesus monkey model. After two intramuscular immunizations with recombinant MVA-SIVSM gag pol, the monkeys developed a Gag epitope-specific CTL response readily detected in peripheral blood lymphocytes by using a functional killing assay. Moreover, those immunizations also elicited a population of CD8+ T lymphocytes in the peripheral blood that bound a specific major histocompatibility complex class I/peptide tetramer. These Gag epitope-specific CD8+ T lymphocytes also were demonstrated by using both functional and tetramer-binding assays in lymph nodes of the immunized monkeys. These observations suggest that MVA may prove a useful vector for an HIV-1 vaccine. They also suggest that tetramer staining may be a useful technology for monitoring CTL generation in vaccine trials in nonhuman primates and in humans.  相似文献   
69.
The effect of cholisorb and its salt (Na and K) forms on the external secretion of the liver was studied. The cholagogic effect of the H-form of cholisorb and its salt forms was demonstrated in dog experiments. The effect of the H-form proved to be stronger. This effect was associated with decreased absorption of bile acids and cholesterol in the intestine and disturbed hepato-intestinal biliary cycle as a result of which adaptation mechanisms directed at restoration of this cycle are apparently switched on.  相似文献   
70.
BACKGROUND: Pediatric urologic specialists have been excluded from many recent managed care contracts because they are believed to be more expensive and of no better quality than general urologists in managing common urologic problems in children. We believed this to be inaccurate. OBJECTIVES: To compare the length of stay at the University of California, San Francisco Medical Center for 2 common pediatric urologic operative procedures with data from other northern California hospitals and to document our results and patient satisfaction. DESIGN: Retrospective analysis of HCIA statewide database (HCIA Inc, Orange, Conn). SETTING: Northern California, 1995. SUBJECTS: Children younger than 12 years undergoing surgery for repair of an obstruction of the ureteropelvic junction or vesicoureteral reflux. MAIN OUTCOME MEASURE: Length of stay. RESULTS: The length of stay in our hospital was similar to that observed in other hospitals in which other full-time pediatric urologic specialists practiced and was significantly less than that observed in other northern California hospitals, even when adjusted for risk. In fact, a savings of 279 hospital days would have been realized if all patients had the same length of stay as that achieved at University of California, San Francisco Medical Center. In the 38 patients operated on at our center, there was uniform surgical success. Of the parents, 92% (11/ 12) were satisfied with their child's care and 92% (11/ 12) believed they received enough information to know what to expect and how to care for their child at home. There were no data available evaluating quality from other northern California hospitals for comparison. CONCLUSIONS: Our finding that actual and risk-adjusted length of stay were shorter when patients were treated by full-time pediatric urologists, while excellent quality was maintained, suggests that these specialists achieve their results with more efficiency and lower resource utilization than do general urologists. The implication of these results is that exclusive contracting that prevents patients from receiving care from full-time specialists results in overuse of valuable resources and possibly reduced quality. If our results are generalizable, they have important implications for health care reform in the United States.  相似文献   
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