123rc/medical_text huggingface dataset:
Endosonography of pararectal lymph nodes. In vitro and in vivo evaluation. One hundred thirteen patients with carcinoma of the rectum were evaluated for lymph node metastases by endorectal ultrasound. With the use of 7.5 MHz and based on different echo patterns, two main groups of lymph nodes can be differentiated: hypoechoic and hyperechoic lymph nodes. Compared with pathologic findings, hypoechoic lymph nodes represent metastases, whereas hyperechoic lymph nodes are visualized due to unspecific inflammation. Lymph node metastases can be predicted with a sensitivity of 72 percent and inflammatory lymph nodes with a specificity of 83 percent. The physical basis of the differentiation of lymph nodes was assessed in vitro by the determination of ultrasound parameters (speed of sound, acoustic impedance, attenuation, and backscattered amplitude). The attenuation coefficient of benign lymph nodes [2.5 dB/(MHz x cm)] is significantly higher than the mean value of lymph node metastases [1.3 db/(MHz x cm)]. The results demonstrate that involved nodes can principally be differentiated from not involved nodes. Micrometastases, mixed lymph nodes, and changing echo patterns within inflammatory nodes explain the accuracy rate of 78 percent.
Electroencephalography laboratory diagnosis of prolonged QT interval. Patients with prolongation of the QT interval are at risk for significant neurological morbidity and mortality secondary to ventricular tachyarrhythmias. These patients frequently undergo electroencephalographic (EEG) examination to evaluate episodes of loss of consciousness, which may be associated with convulsions. Electrocardiogram recording as a part of the EEG is a simple and common practice, but analysis for possible QT prolongation is not routinely performed by electroencephalographers. This is, in part, due to the fact that while calculation of the corrected QT interval is straight forward, a calculator is generally required. A nomogram that is presented simplifies determination of the corrected QT interval, facilitating diagnosis of prolongation of the QT interval in the EEG laboratory.
Phosphorus-32-colloidal chromic phosphate: treatment of choice for malignant pericardial effusion. A 68-yr-old male with agnogenic myeloid metaplasia was given phosphorus-32-colloidal chromic phosphate intrapericardially for the treatment of malignant pericardial effusion. Technetium-99m-sulfur colloid was used to verify catheter placement and to visualize distribution within the pericardium. Estimated dosimetry for this mode of therapy is presented, and it is suggested that pericardial administration of phosphorus-32-colloidal chromic phosphate is the treatment of choice for malignant pericardial effusion.
Long-term follow-up of the first 56 patients treated with intracoronary self-expanding stents (the Lausanne experience). Fifty-six patients treated with the self-expanding intracoronary stent for acute occlusion during percutaneous transluminal coronary angioplasty (PTCA) or restenosis were followed for 24 to 43 months (mean 34). Successful deployment and positioning were achieved in 55 of 56 patients. Occlusion of the stent was documented in 8 patients, the earliest occurring 30 minutes and the latest 8 months after implantation. Three of the occluded stents were recanalized by PTCA. Coronary artery bypass grafts (CABG) were required in 4 patients: 1 for symptomatic restenosis, 1 for left main stenosis adjacent to the stent and 2 for acute ischemia during the in-hospital stay (less than 7 days). Myocardial infarction occurred in the territory of the stented vessel in 8 patients. Seven patients died between 1 day and 19 months after implantation. Local bleeding complications occurred in 10 patients, with 5 requiring blood transfusion. Restenosis within the stent was angiographically documented in 5 patients (9%). A new lesion in the treated vessel was found in 10 patients, followed by implantation of a second stent in 5 and a third stent in 1 patient. Medical treatment was instituted in the remaining 4 patients. Forty-nine patients (88%) are alive. Twenty-nine patients (51%) remained asymptomatic, and 44 (78%) are in a better functional class than before the implantation. Eleven of 15 (79%) major complications (acute occlusions or deaths) occurred in patients who received a stent in the left anterior descending coronary artery. In conclusion, implantation of the self-expanding intracoronary stent appears to be a new therapeutic option for treating acute occlusion or restenosis after PTCA.
Intraoperative air testing of colorectal anastomoses: a prospective, randomized trial. A total of 145 consecutive patients receiving a colorectal anastomosis were randomized to 'test' or 'no test' once the anastomosis had been completed. Anastomotic testing was performed with the pelvis filled with saline and the rectum distended by sigmoidoscopic insufflation of air. Any leaks demonstrated were oversewn. A water-soluble contrast enema was performed on the tenth postoperative day. Seventy-four patients were randomized to 'test' and 71 to 'no test' but one patient was withdrawn from each group leaving a total of 143 for analysis. The two groups were well matched for age, sex, diagnosis and operative details. Eighteen (25 per cent) air leaks were detected and repaired in the 'test' group. After operation there were three (4 per cent) clinical leaks in the 'test' group and ten (14 per cent) in the 'no test' group (Fisher's exact test, P = 0.043). There were eight (11 per cent) radiological leaks in the 'test' group and 20 (29 per cent) in the 'no test' group (P = 0.006). Intraoperative air testing and repair of colorectal anastomoses significantly reduces the risk of postoperative clinical and radiological leaks.
Italian experience of voice restoration after laryngectomy with tracheoesophageal puncture. This report concerns 102 cases of tracheoesophageal puncture performed as a means of secondary voice restoration after total laryngectomy, in 70 patients proving unable to learn esophageal speech and as a treatment of choice in a further 32 cases. Complications arose in 21 cases but were generally minor and could be overcome. Results were favorable in 45 of 70 and 29 of 32 cases, respectively. The method was considered effective, particularly when supported by the patient's determination to learn a verbal communication method.
Parkinsonian tremor loses its alternating aspect during non-REM sleep and is inhibited by REM sleep. Non-REM sleep transforms the waking alternating Parkinsonian tremor into subclinical repetitive muscle contractions whose amplitude and duration decrease as non-REM sleep progresses from stages I to IV. During REM sleep Parkinsonian tremor disappears while the isolated muscle events increase significantly.
Video display terminals and the risk of spontaneous abortion. BACKGROUND. The relation between spontaneous abortion and the use of video display terminals (VDTs) is of great public health concern. Previous investigators of this issue have reported inconsistent findings. METHODS. To determine whether electromagnetic fields emitted by VDTs are associated with an increased risk of spontaneous abortion, a cohort of female telephone operators who used VDTs at work was compared with a cohort of operators who did not use VDTs. To obtain reliable estimates of exposure, we determined the number of hours of VDT use per week from company records and measured electromagnetic fields at VDT workstations and, for purposes of comparison, at workstations without VDTs. Operators who used VDTs had higher abdominal exposure to very-low-frequency (15 kHz) electromagnetic fields (workstations without VDTs did not emit very-low-frequency energy). Abdominal exposure to extremely-low-frequency fields (45 to 60 Hz) was similar for both operators who used VDTs and those who did not. Among 2430 women interviewed, there were 882 pregnancies that met our criteria for inclusion in the study. RESULTS. We found no excess risk of spontaneous abortion among women who used VDTs during the first trimester of pregnancy (odds ratio = 0.93; 95 percent confidence interval, 0.63 to 1.38), and no dose-response relation was apparent when we examined the women's hours of VDT use per week (odds ratio for 1 to 25 hours per week = 1.04; 95 percent confidence interval, 0.61 to 1.79; odds ratio for greater than 25 hours per week = 1.00; 95 percent confidence interval, 0.61 to 1.64). There continued to be no risk associated with the use of VDTs when we accounted for multiple pregnancies, conducted separate analyses of early abortion, late abortion, and all fetal losses, or limited our analyses to spontaneous abortions for which a physician was consulted. CONCLUSIONS. The use of VDTs and exposure to the accompanying electromagnetic fields were not associated with an increased risk of spontaneous abortion in this study.
Vaginosonographic measurement of endometrial thickness in the evaluation of amenorrhea. The progestin-induced withdrawal bleeding test has often been used in patients with amenorrhea to assess endogenous estrogen (E) production. The endometrial thickness measured by vaginal ultrasonography with a 5 MHz transducer is also dependent on E stimulation of the endometrium. In this study, 70 consecutive patients were evaluated with both the progestin-induced withdrawal bleeding test and a measurement of the endometrial thickness by vaginosonography. An endometrial thickness of 1.5 mm or less was selected to predict absence of bleeding after a progesterone (P) challenge test. This resulted in a sensitivity of 94% with a 95% confidence interval (CI) of 0.70 to 1.00 and a specificity of 93% with a 95% CI of 0.82 and 0.98. The positive and negative predictive values were 79% and 98%, respectively. This study shows that the endometrial thickness measured by vaginosonography can predict the results of the P challenge test in patients with amenorrhea.
Risk factors for carotid artery stenosis: an epidemiological study of men aged 69 years. Four hundred and seventy-eight men born in 1914 and residing in the city of Malmo, Sweden, underwent ultrasonic Doppler examination of the carotid arteries in 1982/83. The known risk factors for vascular disease--blood pressure, lipids, glucose, hematocrit, alcohol consumption and Body Mass Index were also measured. A moderate stenosis (diameter reduction 30-59%) of the internal carotid artery was found in 95 men (20%); 15 men (3%) had a greater than or equal to 60% stenosis of the internal carotid artery, while 7 (1.5%) had complete unilateral occlusion. Smoking was found to be significantly related to severe carotid artery disease. There was also a significant correlation between maximum flow velocity in the internal carotid artery and triglycerides. Those quitting smoking before the age of 50 had the same incidence of internal carotid artery disease as non-smokers, while those quitting later in life had a slightly higher incidence than life-long smokers.
Nifedipine protects the heart from the acute deleterious effects of cocaine if administered before but not after cocaine. BACKGROUND. We tested the hypothesis that nifedipine, a calcium channel blocker, could ameliorate the toxic effects of cocaine on the myocardium. METHODS AND RESULTS. In an initial protocol, anesthetized dogs were pretreated with nifedipine or saline and then administered cocaine (10 mg/kg, i.v. bolus). Coronary blood flow, heart rate, mean arterial pressure, and the first derivation of left ventricular pressure (dP/dt) were measured at baseline, 2 minutes, and 15 minutes after cocaine administration. Nifedipine pretreatment prevented the early cocaine-induced decrease in coronary blood flow and improved left ventricular dP/dt compared with untreated control animals. After cocaine, ejection fraction fell in the saline group to 37 +/- 3% but increased in the nifedipine group to 59 +/- 4% (p less than 0.05). In a second protocol, vehicle or intravenous nifedipine was administered after an infusion of cocaine (10 mg/kg). In contrast to pretreatment, there was no significant improvement in left ventricular function or coronary blood flow in nifedipine-treated versus control animals. Data from the study also suggested that cocaine acts directly on the myocardium. Within seconds of cocaine bolus administration, coronary blood flow in control animals increased to a peak level 59 +/- 14% higher than before cocaine and left ventricular dP/dt decreased by 23 +/- 5%, providing evidence that cocaine causes direct depression of myocardial function independent of a decrease in myocardial blood flow. CONCLUSIONS. We conclude that nifedipine administered as a pretreatment protects against the depression of myocardial function and decrease in coronary blood flow caused by acute cocaine administration. However, when nifedipine is given after cocaine, no improvement is seen. Cocaine has a direct negative inotropic effect on the heart that is independent of a decrease in coronary blood flow.
The hyperlipidemia of the nephrotic syndrome. Lipid abnormalities in patients with the nephrotic syndrome have long been recognized. However, the significance of these lipid abnormalities, the mechanisms producing them, and their potential treatment have all been a cause of debate. Recent data have helped clarify each of these areas of controversy. Studies of the lipoprotein abnormalities of patients with the uncomplicated nephrotic syndrome have shown that many will have elevated levels of total and low-density lipoprotein cholesterol, whereas only a few will have elevated levels of high-density lipoprotein cholesterol. If these lipid abnormalities have the same significance in this population as in other populations studied, then some patients with unremitting nephrotic syndrome will be at high risk for cardiovascular disease. The elevated cholesterol levels noted in the nephrotic syndrome are caused primarily by enhanced hepatic synthesis, with lesser contributions by decreased clearance and altered enzyme activities. The signal for enhanced hepatic lipogenesis may relate to changes in plasma albumin concentration, plasma oncotic pressure, a local effect of viscosity at the hepatic sinusoidal level, or a loss of urinary proteins or other liporegulatory substances. Recently, a number of short-term studies in nephrotic patients have documented the safety and efficacy of lipid-lowering drugs such as the bile acid-binding resins, probucol, and the HMGCoA (hydroxymethylglutaryl coenzyme A) reductase inhibitors.
Acute limb ischaemia: the place of intravenous streptokinase. Intravenous streptokinase infusions (100,000 units/h) have been used to treat 48 patients, with 50 episodes of acute limb ischaemia who were unlikely to benefit from a surgical approach. These included 17 acute thromboses, 14 late or distal emboli and 19 bypass graft occlusions. Overall, 17 (34 per cent) instances had complete lysis with reappearance of distal pulses and a further 28 per cent had clinical improvement without change in pulse status. Final outcome after 30 days was limb salvage in 60 per cent, amputation in 24 per cent and death in 16 per cent, but this was achieved after eight patients without lysis had vascular reconstructive surgery. Serious complications were infrequent, but included a fatal stroke, a haematemesis and two episodes of distal embolization. The outcome was not related to the duration of ischaemia or the site of occlusion. Lysis was more frequent with emboli (50 per cent) and graft occlusions (47 per cent) than arterial thromboses (6 per cent). Limb salvage was more likely in patients with no neurological deficit in the limb (70 per cent) than if a deficit was present (37 per cent). In conclusion, intravenous streptokinase produced a moderate benefit with low morbidity and has a role in acute limb ischaemia if surgery is inappropriate and intra-arterial lysis unavailable. In particular, selected patients with emboli or graft occlusions without a neurological deficit may be most suitable.
Identification and characterization of a regulated promoter element in the epidermal growth factor receptor gene. We have identified a 36-base-pair proximal element (-112 to -77 relative to the AUG translation initiation codon) in the epidermal growth factor receptor 5' region that functions as a promoter; mediates inductive responses to epidermal growth factor, phorbol 12-myristate 13-acetate, and cyclic AMP; and acts in an orientation-independent manner. This region functions as an enhancer when transferred to a heterologous promoter containing a TATA box. Mutations within the 36-base-pair region alter function as assayed by reporter gene expression in recipient cells. A protein has been identified that demonstrates appropriate binding specificity to mutant DNA sequences that correlates with promoter activity observed in vivo. On the basis of DNA binding characteristics and size, the identified protein appears distinct from several previously identified transcription factors known to bind to G+C-rich regions.
Implications of a dynamical systems approach to understanding infant kicking behavior. Implications of the dynamical systems approach to understanding movement dysfunction in infants are discussed. Traditional theories of motor development attribute changes in movement to the hierarchical maturation of the central nervous system. The dynamical systems approach emphasizes that movement self-organizes as the result of the interaction of the participating subsystems in developmental and real time. In this article, I discuss, from the theoretical perspective of the dynamical systems approach, the organization of leg movements in low- and high-risk preterm and full-term infants, developmental changes in movement in low-risk preterm infants from 34 weeks' gestational age to 40 weeks' postgestational age, and differences in movement between low-risk preterm infants at 40 weeks' postgestational age and full-term infants. Preliminary data on high-risk preterm infants are presented. Based on these data, the necessity to review and reinterpret traditional concepts of motor development is explored. Suggestions are offered and questions posed on how the dynamical systems perspective may influence the practice of physical therapy in the evaluation, and treatment of infants at risk for movement dysfunction.
Arterial blood pressure. Correlation with erythrocyte count, hematocrit, and hemoglobin concentration. The relationship between arterial blood pressure and red blood cell variables was investigated in 1013 unselected persons with a blood pressure range of 90 to 225 mm Hg systolic and 50 to 145 mm Hg diastolic. Statistically significant correlations were demonstrated between mean (as well as systolic and diastolic) arterial blood pressure and red blood cell count (r = 0.27; P less than .0001), hematocrit (r = 0.28; P less than .0001), and hemoglobin concentration (r = 0.29; P less than .0001). Average arterial blood pressure was higher in men than in women (133 +/- 16/83 +/- 10 v 124 +/- 16/79 +/- 9 mm Hg, P less than .0001) and this was associated with higher values for erythrocyte count, hemoglobin concentration, and hematocrit in men as compared to women. The significant correlation of blood pressure and hematocrit, which represents one important determinant of blood viscosity, points to a role for rheological factors in the long-term control of blood pressure. Moreover, it might be speculated that the sex difference in blood pressure as observed in the present study may be due, at least in part, to stimulated erythropoiesis in men as compared to women.
Regional variation in brain lactate in Leigh syndrome by localized 1H magnetic resonance spectroscopy. Localized water-suppressed 1H magnetic resonance spectroscopy was performed in an 11-month-old infant with Leigh syndrome. Spectra obtained from the basal ganglia, occipital cortex, and brainstem showed elevations in lactate, which were most pronounced in regions where abnormalities were seen with routine T2-weighted magnetic resonance imaging. This approach has allowed us to examine metabolism in brain tissue directly and noninvasively, and may provide a sensitive means for evaluating metabolic disease and the response to therapy in the brain.
Left ventricular pseudoaneurysm with hemoptysis. A 53-year-old man who had previously undergone resection of a left ventricular aneurysm was admitted because of hemoptysis. Preoperative evaluation with computed tomographic scan and cardiac catheterization demonstrated a pseudoaneurysm of the inferior ventricular wall measuring 16 cm in diameter with protrusion into the left hemithorax. The neck of the pseudoaneurysm was a defect in the ventricular wall extending from the base of the mitral valve annulus to the insertion of the posterior papillary muscle. Operative repair was performed using an albumin-coated, low-porosity Dacron patch.
Bilateral Norrie's disease in identical twins. A case of Norrie's disease in an identical twins is reported. No positive family history was obtained. The couple had no other children. The older of the twins died at the age of 9 months of uncertain cause. To the best of my knowledge this is the first case of Norrie's disease reported in Malaysia. And its occurrence in an identical twins is very rare.
Elevated pulmonary artery pressure. An independent predictor of mortality. Analyses in this study were based on hemodynamic and angiographic data obtained in a cohort of 1,371 predominantly black patients during right and left heart catheterization. All patients were followed up prospectively for a mean of 117 weeks, and 103 fatal events were recorded. In Cox survival analysis, three variables were found to be independently related to survival: pulmonary artery mean pressure (PAMP), number of stenosed vessels, and left ventricular (LV) ejection fraction (p less than 0.01); in multivariate stepwise analysis, PAMP entered the model first with the largest chi 2 value of the three prognostic variables (chi 2 = 33.4; p less than 0.0001). The PAMP was 32 percent higher in decedents compared with survivors (25 + 11 mm Hg vs 19 + 8 mm Hg, p less than 0.01 [mean, SD]) and a 10 mm Hg increase in PAMP was associated with a more than fourfold increase in the relative risk of dying; this finding was independent of pulmonary vascular resistance and therefore could not be attributed to primary pulmonary vascular or parenchymal disease. In both the subgroup of 1,118 patients with a normal LV ejection fraction (greater than 50 percent) and the 253 patients with a reduced ejection fraction (less than 50 percent), PAMP emerged as an independent predictor of mortality (p less than 0.0001 and 0.01, respectively), and is therefore a marker of cardiac disease beyond impairment of systolic contractile function. Among patients without obstructive coronary artery disease, PAMP alone provided prognostic information in the multivariate survival analysis.
Effect on outcome of prolonged exposure of patients to nitrous oxide. Prolonged (several days or repeated) exposure to nitrous oxide (N2O) can cause injury or death. To assess whether relatively prolonged anesthesia with N2O in normal patients might similarly cause untoward effects, we investigated whether the addition of N2O to isoflurane anesthesia caused injury to patients having surgical resection of acoustic neuroma lasting approximately 10 h. Twenty-six patients undergoing surgical resection of acoustic neuroma were randomly assigned to a regimen that included or excluded N2O (50%-60%) during isoflurane anesthesia plus intravenous adjuvants. On average, slightly less isoflurane (0.24%) was used during anesthesia with N2O. We measured standard clinical variables (blood pressure, heart rate), oxygen saturation, neurologic status, pain, and the incidence and type of morbid outcomes. Exposure to N2O did not increase the incidence of morbid outcomes (including hepatic injury, infection, or hypoxemia), prolong hospitalization, or increase common postoperative complaints such as nausea, vomiting, coughing, or headache. Patients anesthetized with either regimen were equally satisfied with their anesthetic.