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11.
Only modest relationships have been found between cognitive functioning and treatment outcome; there is some indication of better prediction of within-treatment progress. The current study attempted to determine whether either cognitive or sociodemographic/alcohol-related variables were predictive of learning in educational treatment. Eighty-seven male alcoholics were exposed to one hour of instruction on the medical effects of alcohol. Sociodemographic, alcohol-related, and cognitive functioning measures were obtained at the outset of treatment. Knowledge was assessed 24 hours prior to and 24 hours and three weeks after the intervention. Statistically significant increases in knowledge were found both 24 hours and three weeks following the educational intervention; retention of information declined significantly from 24 hours to three weeks post-intervention. Discriminant function analyses using either seven cognitive variables or six alcohol-related/sociodemographic variables significantly discriminated between learners and nonlearners 24 hours after the intervention. The weighted composite of measures in each of the analyses was able to successfully differentiate learners from nonlearners in over 70% of the cases. The findings suggest that the clinician may be able to employ a limited number of variables to differentiate between patients who will and will not be able to acquire knowledge from educational interventions.  相似文献   
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During embryonic development, morphogenetic gradients can specify the formation of gene expression territories. Here, we explore possible commonalities between pattern formation in the Drosophila blastoderm and murine pituitary. Shared principles include the need for positive feedback involving fate-determining genes to maintain a differentiated state, and the existence of intra- or extracellular inhibitory signals that improve spatial resolution of neighboring territories. The precision of spatial segregation is, however, limited by stochastic gene expression. Variability in gene expression at territory boundaries might give rise to a poorly differentiated pool of cells, which could harbor stem-like properties. The ideas outlined here deserve further theoretical and experimental exploration.  相似文献   
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Senile systemic amyloidosis (SSA) results from deposition, predominantly in the heart, of amyloid fibrils derived from wild-type transthyretin (T TR) molecules. Cardiac autopsies indicate that SSA progressively increases in subjects 80 years of age and older. However, only a few cases of patients with SSA and cardiac failure have been recognized by cardiac biopsies during life. Here, we report a case of heart transplantation in a 68-year-old male patient with SSA. After cardiopulmonary resuscitation in October 1998, he underwent complete evaluation. Myocardial biopsies revealed the presence of amyloid deposition. Immunohistochemical staining of the amyloid indicated T TR. Genomic DNA analysis of the T TR exons did not result in any identification of a mutation. In 2001, heart transplantation was performed because progressive heart failure occurred. At the 1-year follow-up, no amyloid deposits were found in the donor heart. At the 2-year follow-up, the patient's physical and mental health was excellent. We conclude that heart transplantation can be an effective treatment in progressive heart failure due to SSA.  相似文献   
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Safety of outpatient tonsillectomy and adenoidectomy   总被引:6,自引:0,他引:6  
Recent changes in reimbursement for tonsillectomy and adenoidectomy have resulted in a large number of these procedures being done on an outpatient basis. There is still considerable controversy, however, as to the safety of this concept. We reviewed the charts of 1000 consecutive patients who underwent these procedures. Three hundred ninety-six procedures were performed as inpatient surgery and 604 were performed as outpatient surgery. Patients were considered as candidates for outpatient surgery if they met specific criteria, such as good overall medical health, no central apnea, normal bleeding history and profile, and had adequate social considerations. The inpatient group included those patients who did not meet the criteria to be outpatients. We compared the complication rates of these two groups with regard to age, type of procedure performed (tonsillectomy, adenoidectomy, adenotonsillectomy), and indication for surgery in order to determine if there was any increased risk of outpatient surgery, despite strict selection criteria. The two groups were similar in their distribution with regards to age, sex, type of procedure, and indication for surgery. The overall complication rate for the entire group was 7.9%, with an 11.8% complication rate for inpatients and 4.1% complications for outpatients. The higher complication rate among the inpatient group is probably a direct result of the selection process because this group included the higher-risk patients. On the basis of these findings, we believe that surgery of the tonsils and adenoids can be performed safely as an outpatient procedure, regardless of age, indication, or procedure, if the candidates for ambulatory surgery are carefully selected by the surgeon.  相似文献   
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Radiographs are ordered and interpreted for immediate clinical decisions 24 hours a day by emergency physicians (EP’s). The Joint Commission for Accreditation of Health Care Organizations requires that all these images be reviewed by radiologists and that there be some mechanism for quality improvement (QI) for discrepant readings. There must be a log of discrepancies and documentation of follow up activities, but this alone does not guarantee effective Q.I. Radiologists reviewing images from the previous day and night often must guess at the preliminary interpretation of the EP and whether follow up action is necessary. EP’s may remain ignorant of the final reading and falsely assume the initial diagnosis and treatment were correct. Some hospitals use a paper system in which the EP writes a preliminary interpretation on the requisition slip, which will be available when the radiologist dictates the final reading. Some hospitals use a classification of discrepancies based on clinical import and urgency, and communicated to the EP on duty at the time of the official reading, but may not communicate discrepancies to the EP’s who initial read the images. Our computerized radiology department and picture archiving and communications system have increased technologist and radiologist productivity, and decreased retakes and lost films. There are fewer face-to-face consultations of radiologists and clinicians, but more communication by telephone and electronic annotation of PACS images. We have integrated the QI process for emergency department (ED) images into the PACS, and gained advantages over the traditional discrepancy log. Requisitions including clinical indications are entered into the Hospital information System and then appear on the PACS along with images and readings. The initial impression, time of review, and the initials of the EP are available to the radiologist dictating the official report. The radiologist decides if there is a discrepancy, and whether it is category I (potentially serious, needs immediate follow-up), category II (moderate risk, follow-up in one day), or category III (low risk, follow-up in several days). During the working day, the radiologist calls immediately for category I discrepancies. Those noted from the evening, night, or weekend before are called to the EP the next morning. All discrepancies with the preliminary interpretation are communicated to the EP and are kept in a computerized log for review by a radiologist at a weekly ED teaching conference. This system has reduced the need for the radiologist to ask or guess what the impression was in the ED the night before. It has reduced the variability in recording of impressions by EP’s, in communication back from radiologists, in the clinical follow-up made, and in the documentation of the whole QI process. This system ensures that EP’s receive notification of their discrepant readings, and provides continuing education to all the EP’s on interpreting images on their patients.  相似文献   
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This paper describes a specific and highly sensitive ELISA system using monoclonal antibodies in order to assay an organophosphorus compound. The soman derivative methyl phosphonic acid, p-aminophenyl 1,2,2,-trimethyl-propyl diester (MATP) served as model substance. In order to obtain antibody-producing hybridomas BALB/c mice were immunized with MATP linked onto human serum albumin (HSA). The spleen cells of immunized mice were fused with syngenic plasmacytomas of the non-producer-line X63Ag8.653 with the aid of polyethylene glycol. To eliminate undesirable cross-reaction, common screening procedures were modified by directly coating the ELISA plates with hapten. Five out of 15 positive cell-lines were cloned by limiting dilution and further propagated. The respective immunoglobulin class and subclass of the obtained monoclonal antibodies was determined. Four of which were identified as IgG1, the other as IgG2a. After enrichment of antibodies in ascites and their isolation by protein A-sepharose, the affinity of various monoclonal antibodies was estimated in competitive inhibition enzyme immunoassay (CIEIA) by measuring the IC50 rates of free MATP. The rates were found to lie between 2.5 × 10–6 mol/l and 4.3 × 10–4 mol/l MATP. The IC10 rate for detectable MATP concentration was 5.4 × 10–7 mol/l MATP. Test duration was 280 min. The reactivity of the monoclonal antibodies with structurally related substances was used to check their specificity. Cross-reaction turned out to be negative. In order to develop a direct competitive ELISA, MATP was linked to horse radish peroxidase (HRPO) by adding a spacer. This helped to reduce total duration to 40 min. The detection level was further reduced to 1.3 × 10–7 mol/l MATP (corresponding to 975 pg/25 l test-buffer) using the monoclonal antibody F71D7. Likewise, MATP was detected in goat serum, chicken serum, rabbit serum, milk and company's water in concentrations between 2.1 × 10–7 mol/l (IC10, company's water) and 4.9 × 10–8 mol/l (IC10, milk).  相似文献   
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