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91.
This article reports a case of an intravenous drug abuser who presented with a hemopneumothorax, which is a rare complication of jugular vein self-injection. The patient achieved an inadvertent subclavian arterotomy, causing tingling and numbness in the hand and arm, an unusual "high," and blood filling the pleura, collapsing the lung. With an increase in pulmonary complications among intravenous drug abusers from infections in the immunocompromised state, pulmonary complaints related to trauma sustained from their activity must not be overlooked.  相似文献   
92.
J A Lown  A L Barr  J M Jackson 《Pathology》1985,17(3):489-492
In recent years, experience with screening protocols for the detection of red cell antibodies has led to a reappraisal of pre-transfusion testing procedures. In the U.S.A. in particular, it has become accepted practice to perform only an antiglobulin crossmatch when an antibody screen has been negative. There is now debate in that country regarding the necessity of retaining even the antiglobulin crossmatch. In this laboratory, as is usual in Australia, room temperature, enzyme and antiglobulin tests are used for both antibody screening and crossmatching. A review was therefore conducted of the results of screening 58,227 samples from approximately 40,000 patients, involving 126,771 crossmatched blood units over a 53 mth period. Eight hundred and seventy-two red cell antibodies were detected in 718 patients. Forty-four of these antibodies were detected only in the crossmatch, and of these 23 were of potential clinical significance. Fourteen of the 23 were detected by the antiglobulin test, 8 by an enzyme test and only 1 by the saline method. Of 107 antibodies detected only in the room temperature phase, none were of clinical significance. The results indicate that exclusion of room temperature tests from all pre-transfusion testing, and deletion of enzyme tests from the crossmatch will not compromise patient safety.  相似文献   
93.
PURPOSE: To report indicators of reliability and validity of the American Board of Internal Medicine Evaluation Form (ABIM-MEF) at one institution (Wright-Patterson Medical Center). METHOD: Completed ABIM-MEFs from 1990-1999 were reviewed. Reliability measures included Cronbach alpha, interrater reliability, and rating consistency between different types of staff and rotations. Construct validity was investigated by tracking ABIM-MEF scores over time and with factor analysis. Predictive validity was assessed by correlating ABIM-MEF scores with the In-training Examination and ABIM Certifying Examination results RESULTS: The 71 residents averaged 12 ABIM-MEFs per year. The forms had a Cronbach alpha of 0.96 and high interrater reliability (intraclass correlation coefficients > 0.80). Ratings did not differ by type of attending or rotation, except that noninternists rated residents lower on procedural skills. ABIM-MEF questions about judgment, knowledge, and clinical skills showed significant improvement from month to month during each academic year as well as year to year. In contrast, questions on professional attitudes, humanism, and procedural skills sections improved between postgraduate year 1 and postgraduate year 2 only. ABIM-MEF questions collapsed into two domains in factor analysis: judgment-knowledge-skills and attitude-humanism. ABIM-MEF questions from judgment and knowledge sections modestly predicted In-training Examination and ABIM Certifying Examination results. In contrast, professional attitude, humanism, and clinical as well as procedural skill questions had little discriminative ability. CONCLUSIONS: The ABIM-MEF appears to be reliable and valid. Further, factor analysis results support the ABIM's movement to simplify the monthly evaluation form to the new Accreditation Council for Graduate Medical Education core competencies.  相似文献   
94.
AIMS: To develop a method of processing non-formalin fixed prostate specimens removed at radical prostatectomy to obtain fresh tissue for research and for correlating diagnostic and molecular results with preoperative imaging. METHODS/RESULTS: The method involves a prostate slicing apparatus comprising a tissue slicer with a series of juxtaposed planar stainless steel blades linked to a support, and a cradle adapted to grip the tissue sample and receive the blades. The fresh prostate gland is held in the cradle and the blades are moved through the cradle slits to produce multiple 4 mm slices of the gland in a plane perpendicular to its posterior surface. One of the resulting slices is preserved in RNAlater. The areas comprising tumour and normal glands within this preserved slice can be identified by matching it to the haematoxylin and eosin stained sections of the adjacent slices that are formalin fixed and paraffin wax embedded. Intact RNA can be extracted from the identified tumour and normal glands within the RNAlater preserved slice. Preoperative imaging studies are acquired with the angulation of axial images chosen to be similar to the slicing axis, such that stained sections from the formalin fixed, paraffin wax embedded slices match their counterparts on imaging. CONCLUSIONS: A novel method of sampling fresh prostate removed at radical prostatectomy that allows tissue samples to be used both for diagnosis and molecular analysis is described. This method also allows the integration of preoperative imaging data with histopathological and molecular data obtained from the prostate tissue slices.  相似文献   
95.
Six hundred and twenty-nine unemployed men were re-interviewed 9 months after initial measurement of their psychological health and commitment to the labour market. For those men remaining continuously unemployed between interviews, no further decrement was observed in mean General Health Questionnaire scores after 3 months without a job, but a significant deterioration was recorded for the sub-sample initially unemployed for less than 3 months. Small but significant declines were observed after 3 months on a single-item measure of reported health and on an 8-item index of commitment to the labour market. For those regaining paid work, all measures of health showed large improvements, and employment commitment was unchanged. Multiple regression analyses were used to examine factors associated with magnitude of changes during continuous unemployment, yielding a systematic pattern of significant relationships. For example, higher employment commitment at initial interview was significantly associated with a greater subsequent decline in psychological health, but not in physical health; reporting a chronic health impairment at initial interview was significantly associated with a greater subsequent decrement in physical health, but not in psychological health.  相似文献   
96.
Exercise and skeletal muscle ageing: cellular and molecular mechanisms   总被引:2,自引:0,他引:2  
As we age, our skeletal muscle becomes smaller and weaker. In addition, the remaining muscle is more susceptible to damage, particularly following exercise, recovery from damage is severely impaired and muscle is unable to adapt rapidly following sequential periods of exercise. The mechanisms by which skeletal muscle damage occurs are poorly understood and the role that an increased production of free radical species plays in this damage is controversial. However, evidence is emerging which suggests that an increased production of free radicals may act as an activator of the adaptive response in skeletal muscle, resulting in the increased production of antioxidant enzymes and heat shock proteins (HSPs). The increased content of these proteins facilitates rapid remodelling of muscle and provides considerable protection against subsequent periods of damaging exercise. There is considerable evidence that the production of free radicals is modified during the ageing process. The aim of this review is to examine the possible effects of this modification on the ability of muscle cells to respond to stress and the functional effect that this may have on our muscles as we age.  相似文献   
97.
Results show that various inbred strains of mice can be segregated into two distinct groups, based on their capacity to allow a number of nontuberculous mycobacterial infections to grow in target organs following experimental intravenous infection. The first group, which allowed these infections to grow progressively, was thus designated as naturally susceptible to these infections; in contrast, those strains which were able to exert detectable bacteriostasis were designated as naturally resistant. It was then found that segregation of mouse strains based on this distinction also mirrored the capacity of these animals to generate acquired immunity to the mycobacterial infections. For example, Mycobacterium simiae grew progressively in susceptible C57BL/6 mice, subsequently triggering acquired mechanisms of immunity, whereas no evidence for acquired immunity could be found in resistant A/Tru mice infected with this organism. The possibility that acquired immunity could not be expressed in the latter strain as a result of a defect in macrophage activation was excluded. Moreover, it was found that the trait of resistance to these infections could be transferred by bone marrow cells into radiation chimeras, thus indicating that this trait was expressed by the progeny of hemopoietic precursor cells. Subsequent backcross analysis to determine the mode of inheritance of the trait of resistance to these mycobacterial infections revealed data that were consistent with the hypothesis that this resistance is controlled by more than one gene. Statistical analysis of the data by the maximum likelihood method suggested polygenic control, although in some cases the probability values suggested control by a major gene, influenced by modifier genes. These findings suggest that the previous hypothesis that the growth of mycobacterial infections in inbred strains of mice is controlled by a single gene should be reevaluated.  相似文献   
98.
Two variants of a continuous recognition training procedure were designed in order to query 2 forms of spatial memory. A continuous reinforcement condition (reflecting perceptual memory) and a differential reinforcement condition (reflecting episodic-like memory) were used to test rats on a 12-arm radial maze. After total hippocampal lesions, rats demonstrated intact performance on the continuous reinforcement condition, but impaired performance on the differential reinforcement condition. After parietal lesions, rats demonstrated the reverse pattern of performance: impaired performance on the continuous reinforcement condition and intact performance on the differential reinforcement condition. Thus, a double dissociation appears to exist between parietal cortex and hippocampus for the continuous reinforcement condition (reflecting perceptual memory) versus the differential reinforcement condition (reflecting episodic memory) for spatial location information.  相似文献   
99.
Monoclonal antibodies were raised against pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 32 KD insulin-like growth factor binding protein (IGF-BP), which represents a major secretory product of the human decidualized endometrium during pregnancy. This class of IGF-BP has been implicated in the modulation of action, inhibitory and stimulatory, of insulin-like growth factors. Immunization with the protein purified from pregnancy endometrium resulted after myeloma fusion in the isolation of six hybridoma clones and the antibodies produced were characterized. The Ka of the antibodies ranged between 4.75 x 10(9) M-1 and 0.7 x 10(8) M-1. In Western blots all monoclonal antibodies reacted with purified protein of molecular weight 32 KD and specifically detected this IGF-BP species in culture medium and cytosolic extracts of pregnancy endometrium and amniotic fluid. The monoclonal antibodies appear to define three epitope-bearing regions as evidenced by their reactivity to polypeptide fragments of the protein. After synthesis and secretion by tissue explants in vitro the protein is susceptible to cleavage into fragments possessing different monoclonal antibody-defined reactivity. Employing immunohistochemical techniques the protein was principally localized to decidual cells in tissue sections of pregnancy endometrium and solely to these cells after enzymic digestion of the tissue. The implications of these results are discussed with respect to potential role of IGF-BP in the action of IGF upon the IGF-1 receptor-bearing populations, including lymphocytes and trophoblast cells, D in the decidua.  相似文献   
100.
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