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71.
Background:  In recent years, success of statistics in field of genetics has been the identification of genes that affect the process of disease. Experimental models using animals enable early stages of tumor development to be studied. The aim of this study was to apply graph models to assess the association between the observed phenotypic changes in rat oral mucosa and induced tumorigenesis in the submandibular gland (SMG).
Materials and methods:  We studied changes in oncogenes TP53 and bcl-2, histopathological and immunomarker variables in samples of oral mucosa and SMG of Wistar male rats, 60 days old and 180 g in weight, in which tumorigenesis was induced in their SMG by a 0.5% solution of 9,10-dimethyl-1,2-benzanthracene in acetone. A set of linear structural equations were defined, with each formula indicating the response variables and the direct influences. In graph models, saliva was considered as a latent variable. The association was analyzed using Graphical Gaussian Markov models and odd ratios.
Results:  About 40% of animals treated with 9, 10-dimethyl-1, 2-benzanthracene showed histological alterations in the epithelial basal strata of their oral mucosa only at 150 days. Statistical models indicated a relationship between gene alteration in gene bcl-2 in the SMG and histological changes observed in the oral mucosa ( P  = 0.04).
Conclusion:  Graph statistical model with one latent variable allows to conclude that these results associated with other clinical parameters may be useful in detecting early changes in SMG tumorigenesis. Furthermore, the design of randomized sampling of oral mucosa allows to validate these results and establish a reliable methodology for presumptive diagnosis or screening in the future.  相似文献   
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The possible antifibrillatory effect of cicletanide, a new diuretic antihypertensive drug, was investigated at random in 50 anesthetized dogs subjected to left circumflex coronary artery ligation for 60 min and later reperfused. In this model, standard electrocardiographic leads 2 and 3 were continuously registered to measure delta R wave percent changes, to count the number of ventricular premature beats, and to document the onset of ventricular fibrillation; aortic pressure was recorded; 6-keto PGF1 alpha and TXB2 plasma levels were determined. Cicletanide significantly reduced early (Phase 1a) postischemic ventricular fibrillation (5 of 25 vs. 12 of 25, p = 0.036) but failed to reduce the incidence of global ischemia-induced ventricular fibrillation. On the other hand, the incidence of postreperfusion ventricular fibrillation was lower in the cicletanide group (1 of 14 vs. 5 of 9, p = 0.04). In addition, the total survival rate was improved in cicletanide treated dogs (p = 0.0257). While the rate-pressure product was lowered by the drug independent of the presence of ischemia, delta R% changes after occlusion were less in treated dogs than in controls. Moreover, the drug reduced significantly the number of ventricular premature beats in the early (Phase 1a) postischemic period. Finally, the drug increased (mean two-fold) the plasma levels of 6-keto PGF1 alpha as compared with controls; however, this increase was less than that achieved (mean 20-fold) after 100 ng/kg/min epoprostenol (prostacyclin) given in a further series of animals. Thus, improved outcome follows 10 mg/kg i.v. cicletanide administration in this model.  相似文献   
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Twenty-four patients with histologically proven metastatic malignant melanoma were included in a Phase II trial of human DNA recombinant interferon (rDNA IFN alpha 2). They were given 10 X 10(6) IU of IFN alpha 2 subcutaneously three times a week until progression of disease or major intolerance developed. Twenty-two patients were evaluable for toxicity and response. General manifestations of intolerance were seen in all the patients. Hematologic toxicity was seen in six patients and therapy had to be interrupted in one patient. Mild liver toxicity was seen in most patients after 2 weeks of treatment. These manifestations disappeared within 2 weeks after treatment was discontinued. A partial response was seen in four cases lasting 2, 4, 4, and 5 months, respectively. There were two complete responses (one skin, one lymph node metastasis) lasting 20 and 6 weeks, respectively. These results indicate a potential role for rDNA IFN alpha 2 in treating patients with metastatic malignant melanoma. However, further trials are required to determine the optimal dose and schedule of administration and modalities of combination.  相似文献   
74.
The purpose of this secondary data analysis of findings from a larger procedural pain study was to examine several factors related to pain during tracheal suctioning. In addition to tracheal suctioning, other procedures studied included turning, wound drain removal, femoral catheter removal, placement of a central venous catheter, and wound dressing change. A total of 755 patients underwent the tracheal suctioning procedure that was performed primarily in intensive care units (93%). A 0-10 numeric rating scale, a behavioural observation tool, and a modified McGill Pain Questionnaire-Short Form were used for pain assessment. Pain intensity scores were significantly greater during the tracheal suctioning procedure (M=3.96, S.D.=3.3) than prior to (M=2.14, S.D.=2.8) or after (M=1.98, S.D.=2.7) tracheal suctioning. Few patients received analgesics prior to or during the procedure. Surgical, younger, and non-white patients reported higher pain intensities. Although mean pain intensity during tracheal suctioning was mild, almost the half of the patients reported moderate-to-severe pain. Individualized pain management must be performed by healthcare providers in order to respond to patients' needs as they undergo painful procedures such as tracheal suctioning.  相似文献   
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The MERIDIAN study examined whether in‐utero MRI (iuMRI) improves the accuracy of diagnosis of foetal brain abnormalities, when used as an adjunct to ultrasound anomaly scanning. A diagnostic iuMRI differs from routine ultrasound screening because of its infrequent use and scanning procedure. Nested within this trial, this sociological study explored the acceptability of iuMRI as a technology and its contribution to parental decision‐making. Our sociological interpretation of the role of iuMR images in prenatal diagnosis draws on narrative interviews with women (and some partners) who underwent MRI imaging at three different centres. Overall, participants found iuMRI helpful in decision‐making because it either confirmed or disconfirmed previous results, or provided additional information. Expectant couples experienced the iuMR imaging process as informative, but also as having emotive and practical value. Our paper extends the existing sociological literature on antenatal testing and visualising the foetus, by using iuMR diagnostic imaging to further explore the concept of the unborn entity. Our data suggest that alongside the iuMR images, the ‘parental gaze’ and accompanying commentary are used by parents to construct and transform foetal and parental identities despite ongoing uncertainties about, and shifting social contexts to their pregnancy.  相似文献   
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