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991.
The clinical course of 60 patients with multiple myeloma was examined for risk factors associated with infection. The overall incidence of infection was 1.46 per patient-year. The greatest risk period for the occurrence of infection was the first two months after the start of initial chemotherapy. The incidence of infection during this period was 4.68 infections per patient-year compared with 1.04 infections per patient-year for subsequent months. Serum creatinine levels of 2 mg/dl or more (p < 0.03) and decreased polyclonal serum immunoglobulins (p < 0.01) predicted increased risk of early infections. Patients infected during the first two months of initial chemotherapy had the same rate of infection during the subsequent clinical course as did patients free of infection during the early treatment period. Thus, the early risk period does not represent only the attrition of susceptible patients. Patients who achieved an objective response had a decrease in infection risk during the time of the response (0.44 infections per patient-year). While response to chemotherapy prolongs life in multiple myeloma, the initiation of chemotherapy is associated with a definable risk period for infections.  相似文献   
992.
Palliative dilation of esophageal carcinoma   总被引:3,自引:0,他引:3  
The authors' experience with palliative dilation of 46 consecutive patients evaluated for squamous cell carcinoma of the esophagus was retrospectively reviewed. Thirty-nine of 46 patients (85%) underwent dilation in order to palliate symptoms, enable endoscopy and biopsy, or prepare for placement of an esophageal prosthesis. Thirty-two of the 46 patients (70%) were treated with radiation therapy and seven (15%) underwent placement of an esophageal prosthesis. Thirty-five of the 39 patients dilated (90%) noted improvement in swallowing, allowing resumption of a soft or regular diet. Complications were noted in three of the 39 patients dilated (8%). The authors conclude that peroral dilation is a safe, effective, and probably underutilized method of palliation in patients with squamous cell esophageal carcinoma.  相似文献   
993.
Nitrates, predominantly venodilators, are commonly used in the treatment of angina pectoris, whereas hydralazine, a potent systemic and coronary arterial vasodllator, is usually contraindicated. Hydralazine might be useful in therapy of angina H tachycardia could be prevented by beta adrenergic blockade. Consequently, treadmill exercise tolerance was determined in 20 patients with chronic stable angina during treatment with oral propranolol, 60 mg four times daily (control), propranolol plus 20 mg of oral isosorbide dinitrate, propranolol plus 100 mg of oral hydralazine, and all three drugs combined. The mean heart rate at rest in patients recelving propranolol was 54.0 ± 1.7 beats/min (mean ± standerd error of the mean). It increased 6.8 beats/min with the additlon of hydralazine (p < 0.005) and 7.2 beats/min with Isosorbide dlnitrate and hydralazine comblned (p < 0.005), but was unchanged with Isosorbide dinitrarate alone. Systoilc blood pressure decreased 13.5 mm Hg with Isosorbide dinitrate (p < 0.05) and 28.3 mm Hg with Isosorbide dinitrate and hydralazine combined (p < 0.005), but did not change significantly with hydralazine alone (average decrease 4.1 mm Hg). The mean duration of exercise increased by 24.1 seconds with Isosorbide dinitrate (p < 0.05), and almost twice that (42.4 seconds longer than the control value) with Isosorbide dinitrate and hydralazine (p < 0.005). With hydralazine alone, exercise duration was decreased by 24.7 seconds (p < 0.05). Rate-pressure product at symptom-tolerated maximal exercise was unchanged with Isosorbide dinitrarate or hydralazine alone, but lower than the control value with the two agents combined. It Is concluded that Isosorbide dinitrate Improves exercise tolerance in patients with angina who are being treated with propranolol, but hydralazine remains detrlmental despite the use of the beta blocking agent. However, when Isosorbide dinitrate is combined with hydralazine, the detrimental effects of hydralazine on exercise tolerance are reversed.  相似文献   
994.
The pathologic and echocardiographic findings of a massive right coronary arterial aneurysm in a 62 year old man are presented. The thrombosed aneurysm simulated a cardiac tumor, destroying one pulmonary valve cusp. It also caused marked pulmonary stenosis with elongation and narrowing of the outflow tract of the right ventricle and fixation of half of one cusp of the tricuspid valve.  相似文献   
995.
The course of 146 consecutive patients with significant occlusive disease of the left main coronary artery who underwent coronary artery bypass surgery during a 4 year period is reviewed. Preoperatively, 11 patients were in New York Heart Association functional class II, 57 in class III and 78 in class IV. Seventy patients had progressive angina and 12 unstable angina. There were two operative deaths (surgical mortality rate 1.4 percent). Seven patients (4.8 percent) had a perioperative acute myocardial infarction. Complete follow-up has been achieved in the surgical survivors over an average period of 18.1 months; 77 percent of the surviving patients are completely asymptomatic and 19 percent are in functional class II. Four patients (2.8 percent) had a nonfatal late postoperative myocardial infarction and five (3.5 percent) died during the late postoperative period (3.3 percent annual mortality rate during a 2 to 47 month follow-up period). Postoperative cardiac catheterization studies performed in 35 patients an average of 12.1 months postoperatively revealed 78 percent of 80 grafts and patency of at least 1 graft in 93 percent of patients. Results of 42 (89 percent) of 47 near maximal treadmill stress tests were abnormal preoperatively compared with results of 14 (26 percent) of 54 postoperatively; in 74 percent of patients having both a preoperative and postoperative stress test, abnormal preoperative test results converted to normal after surgery. This study suggests that direct myocardial revascularization may offer an effective means of improving both the quality and duration of life in a patient with significant occlusive disease of the left main coronary artery.  相似文献   
996.
Patients with mitral stenosis usually showed a marked increase in the P negativity following exercise. The P terminal force in Lead V1 in 20 cases with isolated mitral stenosis was ?0.090 mm. sec. before exercise, which changed to ?0.177 mm. sec. following the single Master two-step test.Normal adults never showed such changes on exercise. The phenomenon was considered to be due to the posterior rotation of the P wave vector in the horizontal plane, which was induced by the enlargement of the left atrial wall on exercise.  相似文献   
997.
Growth hormone and prolactin blood concentrations were measured in five human volunteers over 28-hour periods including 24 hourly samples (0800 to 0800 hours) followed by an oral glucose tolerance test (0800 to 1100 hours) both preexposure and during the peak febrile phase of a self-limited viral infection, Sandfly fever. Several months after recovery, three of the subjects were studied for 24-hour periods while they sat in a tub of water at 41 degrees C for 2 hours from 1300 to 1500 hours. During all studies, mealtimes (0800 hours, 1130 hours, 1630 hours) and dark phase (2300 to 700 hours) were fixed. Growth-hormone concentrations were strikingly elevated throughout the 24-hour study done during the febrile period of Sandfly fever infection (P less than .01) except for the period of normal nocturnal release when they were not significantly different from the baseline study. No additional nocturnal surge was noted the already elevated growth-hormone values during the viral-induced fever. Growth-hormone values tended to decline slowly during the night but increased considerably during the glucose-tolerance test the following morning. These changes were similar to responses previously reported in patients with cases of malnutrition. A clear-cut increase in growth-hormone concentrations (P less than .001) was also seen during a brief 2-hour period of artificial hyperthermia, suggesting that elevated body temperature alone may explain part of the increase in growth-hormone values seen during the fever of infection. A nocturnal surge of growth hormone was still seen in the artificial hyperthermia study, albeit somewhat delayed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
998.
Minoxidil is a potent oral vasodilator of potential value in patients with congestive heart failure (CHF), although preliminary studies show that it causes fluid retention. To test whether minoxidil acts primarily as an arterial vasodilator in CHF, it was compared with hydralazine and nitroprusside. To evaluate its chronic efficacy and mechanism of fluid retention, the effects of minoxidil (7 patients) were compared, in a double-blind manner, with those of hydralazine (8 patients) on central and regional hemodynamics and the renin-angiotensin-aldosterone and sympathetic nervous systems. There was no demonstrable difference in the central hemodynamic effects of minoxidil and hydralazine in the dosages used. After 6 hours both drugs increased cardiac index (minoxidil group, from 1.65 ± 0.29 to 2.26 ± 0.40 liters /min/m2, p < 0.0001; hydralazine group, from 1.88 ± 0.61 to 2.34 ± 0.90 liters/min/m2, p < 0.0001), decreased systemic vascular resistance and increased heart rate without change in pulmonary arterial, pulmonary capillary wedge or right atrial pressures. Nitroprusside effects differed from those of minoxidil and hydralazine with respect to heart rate (p < 0.005) and mean pulmonary arterial (p < 0.007) and right atrial (p < 0.009) pressures. Nitroprusside also decreased relative hepatomesenteric flow compared with the other 2 agents (p < 0.005). Neither renal blood flow, glomerular filtration rate, filtration fraction, nor urinary sodium excretion were significantly altered acutely by any of the 3 drugs. Minoxidil and hydralazine did not differ in their neurohumoral effects: Both agents produced an increase in plasma norepinephrine concentration (p < 0.003) and plasma renin activity (p < 0.04), but no change in plasma epinephrine or aldosterone concentrations. After 1 week of double-blind therapy, fluid retention was a greater problem with minoxidil than with hydralazine. Thus, minoxidil behaves primarily as an arterial vasodilator in CHF, fluid retention is a severe adverse effect, and the greater degree of fluid retention with minoxidil than hydralazine is not attributable to differing acute effects on total renal blood flow or function, or differing effects on the renin-angiotensin-aldosterone or sympathetic nervous systems.  相似文献   
999.
In patients with ventricular or atrial septal defect, the ventricle which is chronically volume overloaded might not appropriately respond to increased demand for an augmentation in output and thereby might limit total cardiac function. In this study we simultaneously measured right and left ventricular response to exercise in 10 normal individuals, 10 patients with ventricular septal defect (VSD), and 10 patients with atrial septal defect (ASD). The normal subjects increased both right and left ventricular ejection fraction, end-diastolic volume, and stroke volume to achieve a higher cardiac output during exercise. Patients with VSD failed to increase right ventricular ejection fraction, but increased right ventricular end-diastolic volume and stroke volume. Left ventricular end-diastolic volume did not increase in these patients but ejection fraction, stroke volume, and forward left ventricular output achieved during exercise were comparable to the response observed in healthy subjects. In the patients with ASD, no rest-to-exercise change occurred in either right ventricular ejection fraction, end-diastolic volume, or stroke volume. In addition, left ventricular end-diastolic volume failed to increase, and despite an increase in ejection fraction, left ventricular stroke volume remained unchanged from rest to exercise. Therefore, cardiac output was augmented only by the heart rate increase in these patients. Right ventricular function appeared to be the major determinant of total cardiac output during exercise in patients with cardiac septal defects and left-to-right shunt.  相似文献   
1000.
Four patients with recurrent, symptomatic ventricular tachycardia (VT) refractory to conventional antiarrhythmic agents were given flecainide acetate to control arrhythmias. Ventricular stimulation studies were performed in all patients before and 1 to 2 weeks after initiation of oral flecainide therapy. Before flecainide, all patients had easily inducible VT that was morphologically identical to their spontaneously occurring arrhythmia. Flecainide increased the mean PR interval (from 0.17 to 0.23 second), mean QRS duration (from 0.08 to 0.12 second) and mean ventricular effective refractory period (from 235 to 270 ms). Mean corrected QT interval did not change (0.51 second).In 2 patients, VT could not be induced during follow-up stimulation studies. One patient has been treated successfully for 10 months, with no clinically apparent episodes of VT. One patient had recurrent nonsustained VT and was withdrawn from the study as a treatment failure after 6 months of therapy. Two patients had inducible, polymorphous VT that degenerated into ventricular fibrillation that required 2 countershocks before the successful restoration of sinus rhythm. One of these patients had VT stimulation by atrial pacing at a cycle length of 320 ms in the postflecainide electrophysiologic study. VT was not inducible by atrial pacing during this patient's preflecainide study.Thus, sustained oral flecainide administration may precipitate serious electrical instability in susceptible patients, and ventricular stimulation studies and other clinical variables may be useful in selecting patients with recurrent VT who may benefit or may be endangered by oral flecainide therapy.  相似文献   
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