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991.
A case of adrenal hemangioma is reported, displayed by computed tomography and confirmed by pathologic investigation. This rare tumor poses a difficult diagnostic challenge and rejoins the problem of incidentally discovered adrenal masses. 相似文献
992.
Pulmonary hypertension (PH) induces high risk of cardiovascular morbidity and mortality, mainly in the primary or essential type. Invasive studies are needed to confirm the diagnosis; among the non- invasive approach, the electrocardiogram has been used to suspect such entity with poor results due to inadequate diagnostic criteria. Twelve children with pulmonary hypertension of the essential type (PPH) and ten children with PH due to interventricular septal defect (VSD) were studied haemodynamically and electrocardiographically and compared to electrocardiographic data of 53 normal children. PPH showed higher resistances than VSD (17.2 +/- 1.9 vs 6 +/- 0.6 u/m2 p less than 0.01) with the same pressure level (99.5 +/- 10.3 vs 101.5 +/- 4.8 mmHg). Right axis deviation, peaked P wave, increased ventricular activation time and prominent ST-T changes were seen in PPH patients whereas in VSD the electrical axis was within normal limits, without P wave changes and in some cases, less conspicuous ST-T abnormalities were observed (p less than 0.01). Such changes showed good sensitivity (80%) and specificity (81%) to suspect PH with resistances higher than 10 u/m2 with a predictive value of 75% (p less than 0.02). P wave and ST-T changes could be of use to suspect PPH with elevated resistances instead of right ventricular hypertrophy voltage criteria. 相似文献
993.
Logistic regression was used to analyze the influence of pretransplant herpesvirus antibodies, in both patients and donors, on the development of acute graft-versus-host disease in 111 consecutive HLA-identical bone marrow recipients. In bivariate analysis, recipient seropositivity for cytomegalovirus (P = 0.01), donor seropositivity for herpes simplex virus (P = 0.02), and low bone marrow cell dosage (P less than 0.05) were associated with a high incidence of grade II-IV acute GVHD. In multivariate analysis the P values were P less than 0.05 for a positive recipient CMV serology and P = 0.07 for a positive donor HSV serology. Positive serology for 1-2 herpes-viruses among recipients or donors both resulted in a 12% incidence of grade II-IV acute GVHD. Positive serology for 3-4 herpesviruses among patients or donors resulted in an incidence of 32% and 38% of acute GVHD, respectively (P less than 0.05). It is concluded that recipient and donor pretransplant herpesvirus immunity can be used to calculate the risk of moderate-to-severe acute GVHD. 相似文献
994.
Converting enzyme inhibition in isolated porcine resistance artery potentiates bradykinin relaxation 总被引:1,自引:0,他引:1
The purpose of this study was to determine the effects of converting enzyme inhibition on the contractile reactivity of porcine femoral and intramuscular resistance arteries. The arteries were dissected free of hind limb skeletal muscle from anaesthetized pigs (Micro-pig Yucatan, Charles River), and were mounted in organ chambers and in a myograph system for tension recording. Bradykinin induced an endothelium-dependent relaxation in both vessels which was potentiated by S 10211, a converting enzyme inhibitor, only in resistance arteries. Under basal conditions angiotensin II and angiotensin I did not contract resistance arteries although contraction could be obtained with other agents such as KCl, noradrenaline or vasopressin. If the tone was increased with noradrenaline, angiotensin II and angiotensin I produced an increase in tension. S 10211 inhibited the increase in tension induced by angiotensin I but not by angiotensin II in vessels with and without endothelium. These results suggest that (1) converting enzyme is present in the vascular wall of porcine resistance arteries, (2) this enzyme is not necessarily located on the endothelial cells and, (3) converting enzyme could influence the responsiveness to angiotensin I and bradykinin. 相似文献
995.
M Boijsen F Goss L Jacobsson C Lamm D Schlossman L Bj?rneld U Tylén 《Acta radiologica (Stockholm, Sweden : 1987)》1988,29(4):419-422
Cardiac output was determined with an indicator dilution technique during digital venous angiography of the left ventricle in 11 patients. The contrast medium injected into the right atrium was used as indicator. During and after the injection of contrast medium one blood sample per second was obtained through a catheter placed in the descending aorta. The samples were analyzed for iodine content with x-ray fluorescence analysis and cardiac output determined ad modum Stewart-Hamilton. Thermodilution was used as a reference method. The results indicate that the indicator dilution method with the use of contrast medium might be used for calibration of videodensitometric methods for blood flow measurements. 相似文献
996.
J. M. Ladero R. Arroyo C. De Andrés F. J. Jiménez-Jiménez J. A. Molina E. Varela de Seijas S. Giménez-Roldán J. Benítez 《Acta neurologica Scandinavica》1994,89(2):102-104
To elucidate whether any relationship exists between genetic polymorphic acetylation and the risk for multiple sclerosis (MS), we determined this polymorphism, using sulphamethazine, in 71 patients with definite MS and in 268 age-matched controls. Thirty-seven patients (52.1%) and 151 controls (56.3%) were classified as slow acetylators (not significant difference). No relation was found between acetylator polymorphism and age at onset of disease in MS patient's group. Our results do not support the existence of any relationship between acetylator polymorphism and the risk for MS. 相似文献
997.
F. Deulofeu J. M. Nava F. Bella C. Martí M. A. Morera B. Font D. Fontanals J. Lite J. Garau A. Calderón M. T. Coll S. Uriz V. Pineda 《European journal of clinical microbiology & infectious diseases》1994,13(8):633-638
The incidence and characteristics of invasiveHaemophilus influenzae disease were studied in 43 adult patients admitted to the acute care hospitals in El Vallés County (Barcelona, Spain) between January 1987 and June 1992. The annual incidence ofHaemophilus influenzae disease was 1.2 per 100,000 inhabitants. Pneumonia occurred in 24 patients, meningitis in five, intraabdominal infections in three, obstetric infections in two, epiglottitis in two and cellulitis in one. In six patients the source of infection was unknown. Ten (23 %) of the infections were hospital acquired. Underlying conditions were diagnosed in 30 (70 %) patients. NontypeableHaemophilus influenzae strains predominated in all adult age groups. Sixty-one percent of type b and 34 % of nontypeable strains were ampicillin resistant (p=0.08). Multiple antibiotic resistance was also high among type b (53 %) and nontypeable (18 %) strains. The mortality rate was significantly higher in patients with pneumonia, bactaeremia from an unidentified focus or shock at presentation. 相似文献
998.
The effects of staphylococci-induced experimental wasting disease on the immune response of 1 month old CD1 mice were investigated. Animals were separated into different subgroups in order to study their cellular immune competence. Malnutrition of wasted mice was associated with anorexia, diarrhea and weakness. Footpad-injected splenic cells produced normal graft vs. host (GvH) reactions in the popliteal lymph nodes of F1 hybrids. In other experiments, the SRBC intragastric feeding of wasted mice did not cause a tolerant anti-erythrocyte humoral immune response. Three weeks after the staphylococci injections, convalescent erythrocyte-fed wasted mice exhibited an anti-SRBC PFC production similar to that observed in non-tolerant immunized control healthy mice. In return, healthy SRBC-fed control mice showed the specific attenuation of antibody response characteristics of oral tolerance. Differences were found between the immune competence of the undernourished staphylococci-treated wasted mice and those shown by other authors in protein-depleted mice. 相似文献
999.
M. Depré D. J. Margolskee A. Van Hecken J. S. Y. Hsieh A. Buntinx P. J. De Schepper J. D. Rogers 《European journal of clinical pharmacology》1992,43(4):431-433
Summary The disposition of the enantiomers of MK-571 (MK-0679 and L-668,018) following single i. v. doses of MK-571 (L-660,711) was studied in a three way cross-over study in 12 healthy male volunteers. Each volunteer received 75 mg, 300 mg and 600 mg i. v. doses of MK-571 at weekly intervals.The disposition of both enantiomers appeared dose-dependent, since the AUC increased disproportionately faster than the dose. The dose dependency was much more pronounced for L-668,018: its AUC increased 6-fold from the 75 to the 300 mg dose, 16-fold from 75 to 600 mg and 2.7 fold from 300 to 600 mg. For MK-0679, the corresponding increases in AUC were 4.8-, ll-, and 2.3 fold. Regardless of dose, the elimination of L-668,018 was more rapid than that of MK-0679.The disposition of MK-0679 needs to be investigated independently to detect any potential influence of L-668,018 on its disposition. 相似文献
1000.