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991.
V Nizet KF Colina JR Almquist CE Rubens AL Smith 《Canadian Metallurgical Quarterly》1996,173(1):180-186
Nontypeable Haemophilus influenzae strain INT1 was isolated from the blood of a young child with clinical signs of meningitis following acute otitis media. No immunologic or anatomic predisposition of this child for invasive bacterial infection with an unusual organism was documented. Sensitive ELISA proved the absence of intra- or extracellular capsular polysaccharide production by INT1 and Southern blot analysis confirmed the lack of an intact capsulation (cap) gene locus within the chromosome. Nevertheless, INT1 established bacteremia and meningitis in infant and weanling rat models of invasive H. influenzae infection. High-molecular-weight DNA isolated from INT1 was shown to confer an invasive phenotype on transformation of a nonencapsulated, avirulent laboratory strain of H. influenzae. Together these findings imply the presence of one or more as-yet-undiscovered, noncapsular virulence factors of H. influenzae that are capable of mediating invasive disease and resistance to immunologic clearance. 相似文献
992.
The study compares, in true adenocarcinoma of the cardia and in adenocarcinoma in Barrett's esophagus, the prevalence of early cancers and their outcome in those patients suitable for resection surgery. From 1980 to 1993, 26 of 350 (7.4%) resected adenocarcinomas of the esophago-gastric junction were pathologically staged as early cancer or pT1. The prevalence of early cancer was 3.7% (11/294) for true cancer of the cardia and 27% (15/56) for cancer in Barrett's esophagus (P < 0.001). Ten of the 15 latter cancers were diagnosed during endoscopic surveillance for benign Barrett's esophagus. Among early cancers, there were four mucosal and 22 submucosal tumours; of the latter, eight had lymph node metastasis and seven neoplastic permeation of lympho-hematic vessels. The most frequently used surgical procedure was esophago-gastric resection and gastric pull-up. Postoperative morbidity was 15.4%, and hospital mortality 3.8%. Excluding postoperative deaths, the overall 5-year survival rate was 79% for early cancer of the cardia and 83% for early cancer in Barrett's esophagus (log rank test = 0.0214, P = 0.88). Overall, the survival rate was 100% in the absence of lymph node metastasis and 43% in the presence of node metastasis (log rank test = 15.811, P = 0.0001). Only one of five patients with both node metastasis and vessel infiltration survived longer than 5 years. In conclusion, the prevalence of early cancer was significantly greater for cancer in Barrett's esophagus than for true cancer of the cardia. Prognosis of the two types of tumour after resection surgery was the same and depended on lymph node status and neoplastic permeation of lympho-hematic vessels. 相似文献
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997.
JL Bullington JC Cameron JE Davis JH Dodd CA Harris JR Henry JL Pellegrino-Gensey KC Rupert JJ Siekierka 《Canadian Metallurgical Quarterly》1998,8(18):2489-2494
Early T-cell receptor mediated signal transduction involves the activation of several tyrosine protein kinases. One of these tyrosine kinases, p56lck, is expressed primarily in T-cells and Natural Killer (NK) cells and has been shown to be critical for their proliferative and effector functions. Indandiones have been identified as a potent and selective chemical class that inhibits p56lck. 相似文献
998.
P Valensi RN Sachs B Lormeau JM Taupin J Ouzan A Blasco A Nitenberg D Metz J Paries O Talvard M Leutenegger JR Attali 《Canadian Metallurgical Quarterly》1997,23(5):409-416
The purpose of this study was to evaluate the ability of three noninvasive techniques to detect silent myocardial ischaemia and analyse the factors associated with this condition, particularly left ventricular hypertrophy, in diabetic patients. An ECG stress test, a thallium-201 myocardial scintigraphy with dipyridamole intravenous infusion, ambulatory 48 h ECG monitoring and an echocardiographic study were performed in 92 diabetic patients without cardiac symptoms but with > or = 2 additional cardiovascular risk factors. At least one of these tests was positive in 28 patients (30.4%), suggesting silent myocardial ischaemia. Twenty-four of these patients had a coronary angiography which showed significant coronary stenosis in only 9 cases. An accurate echocardiographic tracing was obtained in 79 patients, particularly in 7 of the 9 with coronary stenosis. Left ventricular hypertrophy was detected in 34 patients, 6 of whom had coronary stenosis. In patients with left ventricular hypertrophy, the positive predictive values of myocardial scintigraphy and the ECG stress test were respectively 50% and 100%, as compared to only 33% and 11% in those without hypertrophy. In summary, coronary stenoses were found in < 10% of asymptomatic diabetic patients with > or = 2 cardiovascular risk factors, but more frequently in individuals with left ventricular hypertrophy. Thus, silent myocardial ischaemia should be searched for first in diabetic patients with hypertrophy, for which the stress test was the most accurate detection method in this study. 相似文献
999.
L Venkateswaran JJ Jenkins SC Kaste SA Shurtleff JR Downing AS Pappo 《Canadian Metallurgical Quarterly》1997,19(2):172-175
OBJECTIVE: To identify risk factors associated with complicated eclampsia. METHODS: Twenty-four patients with eclampsia complicated by intracerebral hemorrhage, pulmonary edema, renal, hepatic, or respiratory failure, disseminated intravascular coagulation, abruptio placentae, pulmonary aspiration, or hemolysis, elevated liver enzymes, low platelets syndrome were compared retrospectively with 101 uncomplicated eclamptic controls. Information on maternal demographic factors, medical and obstetric histories, and maternal and perinatal outcomes was retrieved and analyzed by univariate and multivariate analysis. RESULTS: By multiple logistic regression, the only risk factors associated with the development of complicated eclampsia were maternal age over 26 years (adjusted odds ratio [OR] 6.3, 95% confidence interval [CI] 2.17, 18.48), multiparity (adjusted OR 4.5, 95% CI 1.55, 13.60) and no prenatal care (adjusted OR 3.3, 95% CI 1.25, 9.60). CONCLUSION: Maternal age above 26 years, multiparity, and no prenatal care are the maternal risk factors identified for the development of complicated eclampsia. 相似文献
1000.
The purpose of this study was to investigate the attitudes towards attempted suicide patients among registered nurses involved in the somatic care of such patients, and to compare them with those of psychiatric nurses. The attitudes were measured on a newly constructed scale, the Understanding of Suicide Attempt Patients Scale (USP-Scale), and three brief clinical vignettes with the answer format of a visual analogue scale (VAS). The nurses working within the psychiatric services were more understanding and more willing to nurse suicide attempt patients than nurses in somatic disciplines. Among all the nurses, older personnel were more favourably disposed than the younger, and more frequent contact with suicide-prone patients was related to more positive attitudes. The perceived need for further training in suicidology was significantly stronger among the nurses in the general hospitals. This suggests that their 'negative attitudes' may to some extent be a result of lack of knowledge and uncertainty rather than a hostile attitude. The nurse has a responsibility to create a positive climate in the patient's encounter with the health services. Knowledge and understanding are needed to enable the nurse to provide professional care for a difficult and challenging patient group. 相似文献