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961.
OBJECTIVE: The purpose of this report is to show that Dacron (DuPont, Wilmington, DE) cuffs retained in breasts after the removal of Hickman catheters may result in complications requiring radiographic evaluation for subsequent management. We also describe potential complications, including infection, associated with a retained cuff and changes after the removal of a retained cuff. CONCLUSION: Because of the increased use of Hickman catheters for central vein access, Dacron cuffs more frequently are retained in breasts and are likely to be seen on mammograms. Radiologists need to be aware of the mammographic findings of a normal cuff, infected cuff, and the site of a surgically excised cuff.  相似文献   
962.
A commercial IgM immunoblot kit was evaluated for dengue diagnosis with a panel of serum specimens collected from patients in a dengue endemic area. The kit is not recommended for use in its present form because of its undesirable rate of false-positive results. However, by substituting internal controls with the reference positive and negative controls that are more representative of those seen in endemic areas and by modifying the positive and negative scoring criteria, sensitivity and specificity of 80.3% and 94.5%, respectively, were obtained. These results are comparable with those obtained with the IgM ELISA on specimens, most of which were obtained from outpatient health care facilities. With further technical modifications, inclusion of a visual guide to ensure scoring standardization, and a more complete elaboration of the limitations of the test, wide application of the kit in diagnostic laboratories should be possible.  相似文献   
963.
Paradoxical cerebral embolism (PCE) through a patent foramen ovale (PFO) should be considered as a cause of ischemic stroke, particularly in young patients without an alternative cause for stroke. PCE is even more important that it is potentially treatable. However, PCE remains often presumed because it rests upon the rarely demonstrated findings of a deep venous thrombosis and a thrombus lodged in the PFO. Recent studies have shown a rather low stroke recurrence rate in patients with PFO and stroke but suggest that some subgroups of patients with a higher stroke recurrence risk-exist according clinical, echocardiographical and radiological characteristics. For these subgroups, it seems that a more invasive treatment should be required. There are four therapeutic options; antiaggregants, anticoagulation, transcatheter closure of PFO, and surgical closure of PFO. However, these treatments have yet to be evaluated in clinical trials.  相似文献   
964.
The phenotype of susceptibility to malignant hyperthermia (MHS); can only be detected reliably by the in vitro caffeine-halothane contracture test (CHCT). Enhanced sensitivity of the calcium-induced calcium release mechanism is responsible for the exaggerated contracture response of skeletal muscle fibers from MHS patients to halothane and caffeine. Chlorocresol was demonstrated to be a potent activator of Ca++ release from skeletal muscle sarcoplasmic reticulum. This effect is probably mediated through action on a ryanodine sensitive Ca++ release channel known to be more sensitive in MH. We studied the effect of chlorocresol on the mechanical contracture response of skeletal muscle from patients presenting for the in vitro CHCT. Chlorocresol induces contracture response in a concentration 1/200 of that of caffeine in muscle strips from MH patients. By adding chlorocresol to the protocol of the CHCT, there is clearer discrimination between the responses of MH patients and normal subjects can be achieved.  相似文献   
965.
Heterogeneity of DNA content in multiple hepatocellular carcinomas (HCCs) was investigated by flow cytometry in 62 tumours from 26 patients who had undergone surgical treatment for multiple synchronous HCCs. Heterogeneity of DNA content was defined (a) when tumours had a different DNA ploidy pattern or (b) when the difference in the DNA index of the aneuploid clone was more than 0.1. A tumour with DNA aneuploidy was observed in 17 (66%) of the 26 patients. Heterogeneity of the DNA content was demonstrated in 12 (46%) out of 26 patients: in ten cases by definition (a) and in two cases by definition (b). Histological examination revealed that, of the 12 patients with a heterogeneous tumour DNA content, seven (58%) had a heterogeneous and the remaining five (42%) had a homogeneous type and grade of differentiation among the tumours, showing the absence of a relationship between histological heterogeneity and DNA content. The present results suggest the clinical relevance of DNA content analysis for identifying the clonal origin of multiple HCCs.  相似文献   
966.
The onset of collagen-induced arthritis in DBA/1 mice is accompanied by a predominantly Th1 response, characterized by production of the proinflammatory cytokines IFN-gamma and TNF-alpha, and a predominance of IgG2a anti-collagen Abs. This study has primarily addressed the effects of continuous administration of exogenous IL-4, a Th2 cytokine, on collagen-induced arthritis in terms of time of onset, clinical symptoms, and histologic changes compared with those in untreated controls. The contributions of Th1 and Th2 cell responses were studied by examining anti-CII IgG subclasses, serum IgE levels, and cytokine production by synovial membrane and lymph node cell cultures. Continuous exposure to IL-4 for 28 days significantly delayed the onset of arthritis from 19 to 37 days and suppressed clinical symptoms. Arthritis occurred approximately 13 to 24 days after treatment ceased. Thereafter, the severity and duration of clinical symptoms were similar to those in control animals, although both joint damage and inflammation at the histologic and cellular levels were less severe than those in untreated controls. During IL-4 treatment, anti-collagen Ab levels were reduced (most significantly those of the IgG2a subclass), histology scores were lower, and the most striking effect was a 1000-fold decrease in TNF-alpha secretion by synovial cells. No significant differences in IgE levels were found between controls and IL-4-treated mice. These data suggest that the anti-inflammatory properties of IL-4 are mediated in part by down-regulation of Th1 responses rather than up-regulation of Th2 responses.  相似文献   
967.
The demonstration of tartrate-resistant acid phosphatase (TRAP) activity has long been a cornerstone in the diagnosis of hairy cell leukemia (HCL). Recently a monoclonal antibody to this enzyme has been developed that can be used in an immunoperoxidase method on paraffin-embedded tissues. By using a peroxidase-labeled streptavidin biotin method, paraffin sections of B5 and formalin-fixed tissue from 86 cases of HCL (41 bone marrow, 36 spleen, 9 liver) were stained with the antibody to TRAP and compared against staining for CD20 (L26) and DBA.44 (DAKO, Carpinteria, Calif). In addition, 193 specimens (127 bone marrow, 42 lymph node, 19 spleen, 5 other) from a variety of neoplastic and nonneoplastic hematologic conditions were stained using the monoclonal antibody to TRAP. For comparison, these cases were also stained with DBA.44. In the cases of HCL, 80 of 86 specimens were immunoreactive for TRAP. While the antibody to TRAP generally stained less than 50% of the hairy cells, CD20 and DBA.44 stained 90% and 50% to 60% of hairy cells, respectively. Two of three cases of marginal zone lymphoma showed weak immunoreactivity to the TRAP antibody. Two specimens from a patient with Gaucher's disease and 8 of 13 cases of mastocytosis also showed positivity to the TRAP antibody in the macrophages and mast cells, respectively. In contrast, staining for DBA.44 was positive in 3 of 9 cases of B-cell large cell lymphoma, 1 of 4 cases of mantle cell lymphoma, and in the paraimmunoblasts of 1 of 7 cases of small lymphocytic lymphoma. Only HCL was TRAP and DBA.44 positive. This antibody to TRAP is a useful addition to the diagnosis of HCL but should be used in conjunction with CD20 and DBA.44. The use of this antibody to determine minimal residual disease after chemotherapy was not addressed.  相似文献   
968.
The effects of two memory-impairing drugs, ethanol and triazolam, on proactive interference (PI) in memory were studied. Following ingestion of either one of these drugs or a placebo, subjects studied an A-B list (e.g., BEE-WASP) of paired associates, followed by an A-C list (e.g., BEE-HONEY) on the interference trial, and a D-E list (e.g., KING-QUEEN) followed by an A-C list on the control trial. A PI effect was found in the data, such that subjects produced fewer correct second list targets on the interference trial than on the control trial. Neither ethanol nor triazolam was found to influence the size of the PI effect. However, both drugs were found to increase B intrusions on the test of the A-C list, to impair subjects' ability to produce more than one studied response for each cue word, and to impair the subjective experience of retrieved memory information. These data suggest that ethanol and triazolam impair an inhibitory process that normally operates as one component of intentional retrieval, playing an important role in the suppression of unwanted information during a memory task.  相似文献   
969.
970.
A prerequisite for higher-level visual tasks such as object recognition is a segmentation of the image into distinct two-dimensional regions. While it has long been assumed that the human visual system jointly exploits region and boundary cues for image segmentation, we report the results of psychophysical experiments which suggest that the visual system relies on geometric properties of bounding contours such as closure and not on the texture of the two-dimensional regions they partition. These findings suggest that the visual system may code and links contours into coherent shapes before surface properties are conjoined.  相似文献   
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