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161.
Two hundred and ninety one women were evaluated for cervical cancer by cytology and colposcopy. Of these, 152 patients underwent colposcopically directed biopsy for histological evaluation. Colposcopy and cytology were in agreement in 88 per cent of cases whereas colposcopy and histopathology were in agreement in 79 per cent of cases. Cytology underestimated the severity of the lesion in nine per cent while colposcopy underestimated the lesion in 7.2 per cent (False negative rate). In 13.8 per cent of cases colposcopy overestimated the lesion (False positive rate). The cone biopsy rate in this series was 30 per cent. We conclude that since colposcopy shows excellent correlation with histopathology, it will be a useful tool to reduce cone biopsy rates, particularly in younger women in the child-bearing age group. 相似文献
162.
Noninvasive Electrocardiographic Imaging (ECGI): Comparison to intraoperative mapping in patients 总被引:3,自引:0,他引:3
Raja N. Ghanem PhD Ping Jia PhD Charulatha Ramanathan PhD Kyungmoo Ryu MS Alan Markowitz MD Yoram Rudy PhD 《Heart rhythm》2005,2(4):212-354
OBJECTIVES/BACKGROUND: Cardiac arrhythmias are a leading cause of death and disability. Electrocardiographic imaging (ECGI) is a noninvasive imaging modality that reconstructs potentials, electrograms, and isochrones on the epicardial surface from body surface measurements. We previously demonstrated in animal experiments through comparison with simultaneously measured epicardial data the high accuracy of ECGI in imaging cardiac electrical events. Here, images obtained by noninvasive ECGI are compared to invasive direct epicardial mapping in open heart surgery patients. METHODS: Three patients were studied during sinus rhythm and right ventricular endocardial and epicardial pacing (total of five datasets). Body surface potentials were acquired preoperatively or postoperatively using a 224-electrode vest. Heart-torso geometry was determined preoperatively using computed tomography. Intraoperative mapping was performed with two 100-electrode epicardial patches. RESULTS: Noninvasive potential maps captured epicardial breakthrough sites and reflected general activation and repolarization patterns, localized pacing sites to approximately 1 cm and distinguished between epicardial and endocardial origin of activation. Noninvasively reconstructed electrogram morphologies correlated moderately with their invasive counterparts (cross correlation = 0.72 +/- 0.25 [sinus rhythm], 0.67 +/- 0.23 [endocardial pacing], 0.71 +/- 0.21 [epicardial pacing]). Noninvasive isochrones captured the sites of earliest activation, areas of slow conduction, and the general excitation pattern. CONCLUSIONS: Despite limitations due to nonsimultaneous acquisition of the surgical and noninvasive data under different conditions, the study demonstrates that ECGI can capture important features of cardiac electrical excitation in humans noninvasively during a single beat. It also shows that general excitation patterns and electrogram morphologies are largely preserved in open chest conditions. 相似文献
163.
Maternal and neonatal acid-base status and glucose metabolism were studied in 20 patients with insulin-dependent diabetes mellitus (group 1) undergoing elective cesarean section under lumbar epidural anesthesia. All patients were given glucose/insulin infusion before delivery. Fifteen healthy patients with iatrogenic hyperglycemia (group 2) and 15 healthy euglycemic patients (group 3) served as controls. Results were expressed as mean +/- 1 SE and were analyzed using analysis of variance and chi 2 analysis at P less than 0.05. No significant differences were seen at delivery either in maternal arterial and neonatal umbilical venous and arterial blood acid-base status or in neonatal Apgar scores among the three groups. Patients in groups 1 and 2 had larger blood glucose concentrations than those in group 3 (P = 0.01). Diabetic mothers and their neonates had a 25%-50% reduction in pyruvate concentration in maternal venous, and neonatal umbilical venous and arterial blood compared with that in the other two groups (P = 0.001). Postpartum neonatal hypoglycemia (less than 30 mg/dL) developed in seven of the group 1 neonates (P = 0.05). Thus, epidural anesthesia in diabetic women is associated with normal acid-base status in the mother and in the neonate. The data also show an increased incidence of neonatal hypoglycemia and altered maternal and neonatal glycolysis in patients with diabetes mellitus. 相似文献
164.
Jayabalan Nirmal Chidambaram Saravana Babu Thanukrishnan Harisudhan Muthiah Ramanathan 《BMC complementary and alternative medicine》2008,8(1):15
Background
Various human diseases have oxidative stress as one of their component. Many herbs have been reported to exhibit properties that combat oxidative stress through their active constituents such as flavonoids, tannins, phenolic compounds etc. Cytisus scoparius (CS) Link, (Family: Leguminosae), also called Sarothamnus scoparius, has been shown in invitro experiments to be endowed with anti-diabetic, hypnotic and sedative and antioxidant activity. Therefore this study was carried out to evaluate CS for its anxiolytic, antidepressant and anti-oxidant activity in stressed rats. 相似文献165.
A Picture Archiving and Communication System (PACS) was installed in the Medical Intensive Care Unit of the Hospital of the University of Pennsylvania. For one year, 8 week periods of FILM ONLY usage were alternated with 8 week periods of PACS OR FILM usage. The time interval between obtaining portable chest images and taking image dependent actions decreased when the PACS was used, however, about 40% of the action decisions were made without a radiologist's consultation. Only 5% of action decisions were made without consultation during the FILM ONLY periods. A new clinical study for measuring diagnostic accuracy and efficiency as well as communication patterns is described. 相似文献
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D M Mirvis J L Wilson K B Ramanathan 《Journal of the American College of Cardiology》1985,6(3):665-673
Prior studies have shown that tachycardia results in ST segment depression in dogs with chronic, gradual coronary occlusion. This response was compared with that produced by acute, total occlusion of the left anterior descending artery. Ten dogs served as controls; in another 10 dogs, an ameroid constrictor was implanted about the left anterior descending artery. This artery was acutely ligated in a third set of 10 animals, and in a final set of 10, the distal left anterior descending coronary vasculature was embolized by latex injection. Tachycardia was produced by atrial pacing from rates of 90 to 250 beats/min using implanted atrial electrodes. Electrocardiographic signals registered from 84 torso electrodes were used to construct body surface isopotential maps during the ST segment. In normal dogs, pacing increased repolarization potentials without shifts in spatial features. New and abnormal anterior negativity, correlating with significant ST depression, appeared at rates of 170 beats/min or faster in dogs with ameroid constriction. However, in both groups with acute occlusion that produced transmural myocardial infarction, tachycardia resulted in increases in anterior ST elevation and reciprocal ST depression. Specific findings demonstrated the lead dependency of the response to tachycardia and the greater than normal increase in potential magnitudes after infarction than in control cases. The similarity of the response with acute occlusion and with embolization suggested that the response to tachycardia after infarction was not dependent on coronary collateral function but may represent a direct electrophysiologic effect of rate. Thus, these acute occlusion models simulate exercise-induced ST segment elevation as it may be seen clinically. 相似文献
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