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961.
When left bundle branch block (LBBB) is present on the electrocardiogram, the diagnosis of left ventricular hypertrophy (LVH) may be difficult. The left ventricular mass in 70 patients with LBBB was estimated by echocardiography, and was compared to the QRS configuration on the electrocardiogram. We found that there was agreement between a monophasic R pattern in lead 1 or V6 (sensitivity 79.3%, 70.7%) and left ventricular hypertrophy. We suggest that a monophasic R pattern in L1 and V6 may provide a useful simple index of left ventricular hypertrophy in the presence of left bundle branch block. 相似文献
962.
End-systolic pressure-volume relations (ESPVRs) were analyzed in 10 closed-chest autonomically blocked dogs before and after volume loading that restored end-diastolic volume to its value measured in the control conscious state. Dogs had been previously instrumented with a left ventricular pressure micromanometer and ultrasonic crystals for measurements of major, anteroposterior, and septum-free wall diameters. Left ventricular volume was calculated with an ellipsoidal model in the left ventricular cavity. ESPVRs obtained during caval occlusion after volume loading were curvilinear as shown by the division of the relation into two parts. The initial part of the relation had a significantly smaller ESPVR slope (Ees, 12.0 +/- 1.8 mm Hg/ml) and ESPVR volume-axis intercept (Vd, - 3.5 +/- 0.8 ml) than the final part of the relation (19.5 +/- 3.1 mm Hg/ml and 0.0 +/- 0.6 ml, respectively, p less than 0.01). The end-diastolic volume-peak dP/dt relation showed a similar curvilinearity when end-diastolic volumes were larger than 1.5-1.7 times the minimal end-diastolic volume reached during caval occlusion. ESPVRs were not different during aortic constriction and caval occlusion when end-diastolic volume was small. In contrast, with large end-diastolic volumes, Ees and Vd were significantly smaller during caval occlusion than during aortic constriction. The final part of ESPVR (with small end-diastolic volume) had the same slope and intercept as that during aortic constriction. We conclude that preload produces a curvilinearity of ESPVR that significantly modifies derived indexes when the range of preload changes is large. 相似文献
963.
Establishing the diagnosis of drug-induced pneumonitis is always difficult and requires that the following criteria be met: administration of the drug on a long-term basis; knowledge that the drug is able to induce pulmonary disorders; occurrence during therapy of interstitial pneumonitis with clinical, radiological and functional characteristics of this type of lung disease; exclusion of all other causes of interstitial pneumonitis (cardiac failure, infections, collagen vascular diseases, malignancies); bronchoalveolar lavage specimen, revealing lymphocytosis with an inverted CD4/CD8 lymphocyte ratio, isolated or associated with neutrophil and/or eosinophil alveolitis; finally, full recovery within several weeks or months after drug withdrawal unless irreversible pulmonary fibrosis has occurred. Certain specific characteristics correspond to the therapeutic class of the drug, i.e. antimicrobial, cardiovascular, antiinflammatory, neurological, metabolic, antiallergy or some other drugs. 相似文献
964.
B Jouve F Collet R Cointe P Barragan P Bru M Metge A Vaillant A Elkouby C Malmejac R Gérard 《Archives des maladies du coeur et des vaisseaux》1989,82(3):337-343
Between 1977 and 1987, 27 consecutive patients (16 men, 11 women, mean age 66 years, range 54 to 75 years) with ventricular septal rupture complicating acute myocardial infarction underwent surgical repair. The purpose of this retrospective study was to analyse the post-operative mortality factors from clinical, haemodynamic and operative data in all patients and also from coronary angiographic data in 23/27 patients whose haemodynamic status allowed this type of exploration. Seventeen patients (63 p. 100) died during the first post-operative month, 10 survived and were discharged. Factors that influenced the prognosis were: (1) inferiorly-located necrosis associated with a 75 p. 100 mortality rate (9 out of 12 patients), as opposed to 53 p. 100 (8 out of 15 patients) with anterior necrosis; (2) right ventricular dysfunction, observed in 83 p. 100 of patients with inferior necrosis and 53 p. 100 with anterior necrosis, which was responsible for 7 out of 9 deaths in the inferior necrosis subgroup and contributed to 3 out of 8 deaths in the anterior necrosis subgroup; this established a cause-effect relationship between right ventricular function and the overmortality of patients with inferior necrosis; (3) independently of the haemodynamic status, two- and three-vessel lesions (56 p. 100 of all lesions) which had an 84 p. 100 mortality rate as opposed to 40 p. 100 with one-vessel lesions; (4) the presence of a state of shock which was associated with a 78 p. 100 mortality rate as opposed to 55 p. 100 in patients without shock. We conclude that when permitted by the patient's haemodynamic status coronary angiography should be part of the pre-operative evaluation to assess the operative risk and guide the surgical procedure. 相似文献
965.
Although fully explored in larger animals, the role of injection site and sample microsphere content on variability of coronary blood flow (CBF) measurement using the microsphere technique remains controversial in rats despite the fact that this species is extensively used in cardiovascular research. We therefore investigated these variables in two studies. In a first study, we established that the precision of the method, assessed by the variability of four simultaneous CBF determinations, was a function of the sample microsphere number. Coefficient of variation (CV) averaged 4-10% when the tissue and reference samples received greater than 1000 and greater than 100 spheres, respectively, and did not improve appreciably with larger numbers of microspheres. In a second study, flow CV was measured following left atrial (LA) or left ventricular (LV) microsphere injections performed nearly simultaneously in the same conscious animal or in two similar groups of animals. CBF variability was lower by 22-62% after LA than after LV injections. Estimates obtained from separate analysis of the main variability components indicated that, with one exception, the variability associated with LV injections was at least 1.4 to 2.8 times higher than that due to LA injections. These findings establish the minimum number of microspheres needed to obtain precise blood flow determinations in the rat model and confirm previous reports, in anaesthetised rats, that LA microsphere injections generally yield more precise coronary blood flow determinations than LV injections. 相似文献
966.
J A Gottridge B R Meyer N S Schwartz R S Lesser 《Archives of internal medicine》1989,149(7):1660-1662
To determine the value of chest roentgenograms in the management of asymptomatic persons with positive tuberculin skin test results, we undertook a retrospective review of all tests administered by our Employee Health Service, North Shore University Hospital, Manhasset, NY, between July 1, 1983 and November 1, 1987. Of 5200 tests, 247 results were positive. Two hundred twenty-one of these charts were reviewed for roentgenographic results and the presence of symptoms. All persons were asymptomatic. Chest roentgenograms revealed the following: normal, 188; unrelated abnormalities, 24; apical pleural thickening, 5; granulomas, 2; calcified hilar node, 1; and calcified node plus granuloma, 1. We noted no active tuberculosis, nor did the chest roentgenographic results influence recommendations for isoniazid prophylaxis. We conclude that chest roentgenograms are of value in 0% to 1.3% of asymptomatic people with positive tuberculin test results. A larger study should be undertaken to further define the usefulness of chest roentgenograms in this population. 相似文献
967.
968.
This study determined nursing research priorities and focused on the development of a nursing research program within a single institution. Of the 715 nurses within the Department of Nursing, 286 (40%) responded to the first round of a two-round Delphi technique, and 137 (48%) responded to the second. The following clinical priorities were determined: prevention and treatment of pressure sores, pain management, treatment of nosocomial infections, and patient education. Nonclinical priorities included staffing and its effects on turnover and patient care, job satisfaction, and factors influencing the quality of nursing care. Serendipitous findings underscored the relevance of the Department of Nursing's conceptual framework to nursing practice and research, revealed the need for dissemination of current research results, and suggested that nurses want to participate in research without assuming responsibility beyond their expertise. 相似文献
969.
970.
The aim of the present investigation was to study the pineal activity during the seasonal gonadal cycle in both sexes of the Indian tree pie (Dendrocitta vagabunda). The findings revealed that the nuclear diameter of the pineal parenchymal cells moderately decreased and was followed by a moderate increase in the cell population density (per microscopic field of the pineal sections) and serotonin content of the gland during the progressive phase. The values of these parameters were further altered (decreased nuclear diameter with increased cell population density and serotonin level) during breeding but were reversibly altered to some extent during the regression phase, and further altered during the nonbreeding phase in both sexes of the birds. It is suggested that the pineal activity distinctly varies with the seasonal gonadal cycle, being minimum during breeding and maximum during nonbreeding in both sexes of the tree pie. 相似文献