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991.
992.
Changes in depression during and following pregnancy   总被引:1,自引:0,他引:1  
Summary. .Rates of depression were studied in a sample of over 9000 women who were participants in the Avon Longitudinal Study of Pregnancy and Childhood. Assessments of depression were made at 18 and 32 weeks gestation, and at 8 and 32 weeks postpartum. Changes in depressive status across time were modelled using latent Markov modelling methods. This analysis showed that when classification errors were taken into account there was relatively high stability in diagnostic status during pregnancy and after pregnancy. However, the transition from late pregnancy to the early postnatal period showed evidence of increased instability and remission of depression. The net effects of this were that rates of depression tended to decline following childbirth. The implications of these results for a series of issues including measurement errors in depression reports and the prevalence of depression before and after childbirth are discussed.  相似文献   
993.
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   
994.
Context.— The use of serologic testing to diagnose Lyme disease (LD) is a source of controversy. Expert recommendations also discourage the routine use of antibiotic therapy for prophylaxis of LD following tick bites, but the extent to which physicians in endemic areas have adopted these recommendations is not known. Objective.— To assess the pattern of use of serologic testing and antibiotic therapy for tick bites and LD and associated charges for management in an endemic area. Design.— Active surveillance of patient-physician encounters for tick bites and LD. Setting.— Primary care practices on the Eastern Shore of Maryland. Patients.— Consecutive sample of 232 patients with tick bites, LD (defined by physician diagnosis in medical record), and suspected LD (physician notation of possible, but not definite LD) seen in 1995. Main Outcome Measures.— Serologic testing for LD, test results, antibiotic therapy, and direct costs of management. Results.— Surveillance identified 142 patients (61.2%) with diagnoses of tick bites, 40 patients (17.2%) with LD, and 50 patients (21.6%) with suspected LD. Of the 142 patients seen for tick bites, 95 (67%) underwent serologic testing for LD. Of these, 93 patients had initial negative or equivocal results; 24 (26%) of the 93 had convalescent testing, with 1 seroconversion. Seventy-eight patients (55%) with a diagnosis of tick bite received antibiotic therapy. No patients with tick bite developed clinical LD. Serologic testing for LD was performed for 36 patients (90%) with a diagnosis of LD and 46 patients (92%) with suspected LD. In most cases, antibiotics were prescribed before serologic test results became available. Convalescent testing was not performed for 37 (86%) of the 43 patients with suspected LD who had initial negative or equivocal results. Of these 37 patients, 25 (68%) did not receive antibiotic therapy. Direct charges for treatment of these 232 patients totaled $47595, one third of which was attributable to serologic testing. A total of 32% of direct charges were for patients with tick bites, 48% were for patients with LD, and 20% were for patients with suspected LD. Conclusions.— In this setting, most patients consulting physicians for tick bites received prophylactic antibiotic therapy of unproven efficacy and underwent unnecessary, costly serologic testing. Despite almost universal use in this study, serologic testing for LD did not appear to influence treatment of patients diagnosed as having LD.   相似文献   
995.
996.
997.
998.
An apparently balanced de novo reciprocal translocation t(5;21) (q13;q22) was demonstrated in a girl with acrobrachycephaly, ventriculomegaly, pulmonary stenosis and anal malformation. The possible relationships between her karyotype and malformations are discussed.  相似文献   
999.
In June 1993, conjoined twins Amy and Angela Lakeberg became the focus of national attention. They shared a complex six-chambered heart and one liver; only one could survive separation surgery, and even her chances were slim. The medical challenge was great and the ethical challenges were even greater.  相似文献   
1000.
Fifty pregnancy alloantisera directed towards HLA-A23 and/or A24 antigens were investigated serologically in titration studies against the three sequenced HLA-A9 specificities, A23 (A*2301), A24 (A*2402) and A2403 (A*2403). The reaction patterns of the antisera fell into five categories which allowed the three HLA-A9 specificities to be easily differentiated. Based on the various titre cytotoxicity scores of the antisera five possible antibody specificities were defined: anti-A23; -A24; -A23/24; -A24/2403 and anti-A23/24/2403. One antiserum crossreacted with HLA-A1 and A24. Inspection of the amino acid sequences of 136 HLA-A, B and C molecules allowed the prediction of five unique epitopes corresponding to these antibody specificities, a possible epitope unique to A2403 and confirmation of a likely epitope shared by A1 and A24. These, together with the previously suggested epitopes HLA-A9/ A2/A28 and A1/A23/A24 together with the presence of Bw4 on the three HLA-A9 antigens suggests that the HLA-A9 family of antigens is characterized by a minimum of nine serologically definable epitopes.  相似文献   
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