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41.
The color complementation assay (CCA) is a method of allele-specific DNA amplification by which competitive priming and extension of fluorescently labeled oligonucleotide primers determine the color of DNA amplification product. This diagnostic method precludes the need for radioisotopes, electrophoresis, and multiple high-stringency reaction conditions. The multiplicity of mutant globin genes present in Southeast Asians complicates clinical diagnosis and underscores the importance of DNA-based diagnostic methods. We have applied CCA to distinguish beta A and beta E alleles. Competing 15mer primers were a fluorescein-labeled complement to beta A and a rhodamine-labeled complement to beta E, identical except for their central nucleotides. A common unlabeled primer was used to amplify DNA product, the color of which was determined by the perfectly complementary primer. Color photography and spectrofluorometry, as well as a method of black-white photography that we developed to distinguish fluorescein- and rhodamine- labeled DNA, were used to record results. We applied CCA to define the complex genotype of a Thai woman with thalassemia intermedia, 96% HbE, and 4% HbF whose possible genotypes included several permutations of alpha-thalassemia, beta-thalassemia, and beta E genes. zeta-Globin gene mapping of DNA doubly digested with Bg/II and Asp 718 showed the -alpha 3.7/--SEA genotype, and CCA confirmed homozygous beta E/beta E. The CCA is useful for diagnosing the compound hemoglobin genotypes of Southeast Asians and could be applied also to prenatal diagnosis in this population.  相似文献   
42.
Ganesan  TS; Min  GL; Goldman  JM; Young  BD 《Blood》1987,70(3):873-876
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone.  相似文献   
43.
Clinical Rheumatology - Little is known about the long-term association of CRP levels during psoriatic arthritis (PsA) disease course. In this study, we examined whether raised CRP over the disease...  相似文献   
44.
Clinical Rheumatology - To (1) determine the reliability and validity of the Bristol Rheumatoid Arthritis Fatigue scale (BRAF-NRS) in patients with psoriatic arthritis (PsA) and (2) examine...  相似文献   
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PURPOSE: To establish a general methodology for quantifying streamline-based diffusion fiber tracking methods in terms of probability of connection between points and/or regions. MATERIALS AND METHODS: The commonly used streamline approach is adapted to exploit the uncertainty in the orientation of the principal direction of diffusion defined for each image voxel. Running the streamline process repeatedly using Monte Carlo methods to exploit this inherent uncertainty generates maps of connection probability. Uncertainty is defined by interpreting the shape of the diffusion orientation profile provided by the diffusion tensor in terms of the underlying microstructure. RESULTS: Two candidates for describing the uncertainty in the diffusion tensor are proposed and maps of probability of connection to chosen start points or regions are generated in a number of major tracts. CONCLUSION: The methods presented provide a generic framework for utilizing streamline methods to generate probabilistic maps of connectivity.  相似文献   
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Background

The significance of tumor markers in patients with appendiceal carcinomatosis is poorly defined. We determined preoperative and postoperative tumor marker levels in patients undergoing cytoreductive surgery (CRS) and heated intraperitoneal chemoperfusion (HIPEC) and examined their association with clinicopathologic features and survival.

Methods

A total of 176 patients undergoing attempted CRS/HIPEC for appendiceal carcinomatosis had at least 1 tumor marker measured. Marker levels were correlated with tumor characteristics and oncologic outcomes. Kaplan–Meier curves and multivariate Cox regression models were used to identify prognostic factors affecting progression and survival.

Results

At least 1 marker was elevated prior to CRS/HIPEC in 70 % of patients (CEA, 54.1 %; CA19-9, 47.7 %; CA-125, 47.2 %). Among patients with elevated preoperative marker levels, normalization occurred postoperatively in 79.4 % for CEA, 92.3 % for CA19-9, and 60 % for CA-125. Absolute preoperative tumor marker levels correlated with peritoneal carcinomatosis index (PCI) (p < .0002), and the number of elevated markers was associated with PCI and progression-free survival (PFS). Elevated postoperative CEA level was associated with decreased PFS (median, 13 vs 36 months, p = .0008). On multivariate Cox regression analysis, elevated preoperative CA19-9 was associated with shorter PFS (hazard ratio [HR] 2.9, 95 % confidence interval [95 % CI] 1.5–5.3, p = .0008), whereas elevated CA-125 was associated with shorter overall survival (HR 2.6, 95 % CI 1.3–5.4, p = .01).

Conclusions

Most patients with appendiceal carcinomatosis will have at least 1 elevated tumor marker and will normalize following CRS/HIPEC, allowing for ongoing surveillance. CA19-9 is a promising biomarker for early progression following CRS/HIPEC, whereas CA-125 is associated with shorter survival.  相似文献   
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Background: Echocardiographic imaging using a handheld transducer in conjunction with treadmill exercise testing is commonly used for the diagnosis of coronary artery disease. Motion of the hand and the transducer during peak exercise preclude optimal imaging. To circumvent the limitations of handheld transducers, we developed a low profile transducer (CONTISON) which can be attached to the chest wall for continuous cardiac imaging. Methods and Results: This feasibility study was performed in 10 normal male subjects (28 to 36 years). The ultrasound transducer was placed in the third or fourth intercostal space at the left sternal border to permit imaging of the left ventricle in its short axis. The transducer was interfaced with a commercially available ultrasound machine. The left ventricle was imaged at rest and while subjects exercised according to a standard Bruce protocol. All segments of the left ventricular short axis were seen at rest and peak exercise. Increased left ventricular wall thickening and wall motion were seen at peak exercise. There were no complications from the procedure. Conclusion: We demonstrated the feasibility of hands‐free left ventricular imaging during treadmill exercise using the CONTISON transducer. Further evaluation of the technique to detect stress‐induced wall motion abnormalities, as a means of diagnosing myocardial ischemia, appears warranted. (ECHOCARDIOGRAPHY 2010;27:563‐566)  相似文献   
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