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101.
An abnormal increase in numbers of CCGG sites methylated in the 5' region of the human calcitonin (CT) gene occurred in tumor cell DNA samples from 90% (17 of 19) of patients with non-Hodgkin's T and B cell lymphoid neoplasms and in 95% (21 of 22) of tumor cell DNA samples from patients with acute nonlymphocytic leukemia (ANLL). The changes were not seen in patients with chronic myelogenous leukemia (0 of 9). The abnormal methylation patterns appear to be a property only of transformed or malignant cells since they were not found in DNA from nonneoplastic adult tissues including sperm, early myeloid progenitor cells, benign lymphoid hyperplasia, peripheral lymphocytes stimulated to divide, or early myeloid progenitor cells (obtained by immunoaffinity using anti-My-10 antibody), but they did appear after Epstein-Barr virus transformation of lymphocytes. Moreover, during the course of therapy in patients with ANLL, the hypermethylation pattern reflects the presence of the leukemic clone even in normal-appearing granulocytes derived from this clone. The increased methylation of the CT gene may then provide an important molecular marker for biologic events in human cell transformation or tumor progression and may prove clinically useful in monitoring patients with lymphoid and acute myelogenous neoplasms.  相似文献   
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103.
Bower  M; Parry  P; Carter  M; Lillington  DM; Amess  J; Lister  TA; Evans  G; Young  BD 《Blood》1994,84(11):3776-3780
Rearrangements of the human trithorax gene (MLL, HRX, Htrx-1, All-1) were studied by Southern blotting in blast cells stored at presentation from 65 adults with de novo acute myelomonocytic (AML-M4) and acute monocytic leukemia (AML-M5). MLL rearrangements were demonstrated in 15 (23%) cases, including eight patients in whom karyotype analysis had failed to detect abnormalities of chromosome band 11q23. The patients with MLL rearrangements did not differ significantly from those with germline configurations in terms of the sex and age of the patients, the presence of lymphadenopathy, hepatosplenomegaly, or central nervous system involvement, and the absolute blast count at diagnosis. Kaplan- Meier analysis of the treated patients demonstrated no difference in survival for patients with MLL rearrangements compared with those without rearrangements. Therefore, in contrast to infantile acute leukemia, in adults with AML-M4 and AML-M5, MLL rearrangements do not identify a subgroup of patients with different clinical features or prognosis.  相似文献   
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106.
The prognostic significance of disease features recorded at the time of diagnosis was examined among 813 patients with Philadelphia chromosome- positive, nonblastic chronic granulocytic leukemia (CGL) collected from six European and American series. The survival pattern for this population was typical of "good-risk" patients, and median survival was 47 mo. There were multiple interrelationships among different disease features, which led to highly significant correlations with survival for some that had no primary prognostic significance, such as hematocrit. Multivariable regression analysis indicated that spleen size and the percentage of circulating blasts were the most important prognostic indicators. These features, and age, behaved as continuous variables with progressively unfavorable import at higher values. The platelet count did not influence survival significantly at values below 700 X 10(9)/liter but was increasingly unfavorable above this level. Basophils plus eosinophils over 15%, more than 5% marrow blasts, and karyotypic abnormalities in addition to the Ph1 were also significant unfavorable signs. The Cox model, generated with four variables representing percent blasts, spleen size, platelet count, and age, provided a useful representation of risk status in this population, with good fit between predicted and observed survival over more than a twofold survival range. A hazard function derived from half of the patient population successfully segregated the remainder into three groups with significantly different survival patterns. We conclude that it should be possible to identify a lower risk group of patients with a 2-yr survival of 90%, subsequent risk averaging somewhat less than 20%/yr and median survival of 5 yr, an intermediate group, and a high- risk group with a 2-yr survival of 65%, followed by a death rate of about 35%/yr and median survival of 2.5 yr.  相似文献   
107.
Koziner  B; Kempin  S; Passe  S; Gee  T; Good  RA; Clarkson  BD 《Blood》1980,56(5):815-823
Analysis of the morphological and immunologic [surface (Sm Ig) and cytoplasmic (Cy Ig) immunoglobulin, faintness (f.imfl) or brightness (b.imfl) of surface immunofluorescence, rosette formation with mouse erythrocytes (MR), or sheep red cells coated with C3 (EAC)] characteristics of the neoplastic lymphocytes involved in 137 cases of B-cell leukemias allowed the differentiation of the following cytologic categories: B1 small lymphocytes (71); SM Ig+, f.imfl., Cy Ig-, MR+, EAC+; B2 prolymphocyte (4): SM Ig+, b.imfl., Cy Ig-, MR+, EAC+. B3 plasmacytoid lymphocyte (2): Sm Ig+, b.imfl., Cy Ig+/-, MR+!-, EAC+/- B4 small cleaved lymphocyte (23): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC+. B5a large cleaved and B5b noncleaved lymphocytes (14): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC-. B6 small noncleaved "Burkitt-like" lymphocyte (5): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC-. B7 plasma cell (2): Sm Ig+, MR-, EAC-. B8 hairy cell (16): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC-, also exhibiting ingestion or attachment of particulate material, not seen in other types. Improved delineation of the heterogeneous group of B-cell leukemias might be of developmental significance in lymphocyte differentiation and improve current prognostic and therapeutic criteria.  相似文献   
108.
Background. Ankle-brachial index (ABI) is an excellent methodfor the diagnosis of peripheral arterial disease (PAD) whenit is performed with Doppler. However, this device is not alwaysavailable for primary care physicians. The ABI measured withstethoscope is an easy alternative approach, but have not beenproved to be useful. Objective. To assess the accuracy of the ABI measured usinga stethoscope comparatively to that of the current eligiblemethod for the diagnosis of PAD, the Doppler ABI, and describethe characteristics of this new approach. Methods. We conducted a diagnostic study of ABI measured witha stethoscope and a Doppler probe and compared the results.Eighty-eight patients were accessed by both methods. Results. Mean stethoscope ABI, 1.01 ± 0.15, and meanDoppler ABI, 1.03 ± 0.20, (P = 0.047) displayed a goodcorrelation. Measurements of stethoscope ABI diagnostic accuracyin recognizing a Doppler ABI are described. The comparison ofthis data with the current gold standard method results gavea sensitivity of 71.4% [95% confidence interval (CI), 41.9–91.6]and specificity of 91.0% (95% CI, 81.5–96.6), with predictivepositive value of 62.5% (95% CI, 38.6–81.5) and negativepredictive value of 93.8% (95% CI, 85.2–97.6). The studyaccuracy was 87.7%. The area under the ROC curve was 0.895 (95%CI, 0.804–0.986, P < 0.0001). Conclusions. According to our study, the stethoscope ABI isa useful method to detect PAD and it may be suitable for itsscreening in the primary care setting. Keywords. Ankle-brachial index, peripheral arterial disease, stethoscope.  相似文献   
109.
Studies suggest a possible antiscarring effect of basic fibroblast growth factor (bFGF) during wound healing. However, little is known about the precise pathological mechanisms of bFGF. In particular, there is only limited information available about the mechanism of exogenous administration of bFGF to scar formation. To investigate the effect of bFGF on the hypertrophic scar in the rabbit ear model and to clarify the mechanisms of bFGF on treatment for scar in wound healing, the rabbit ear model of wound healing was created and treated topically with bFGF once daily for 3 months; then we examined the changes of macroscopic and histopathological characteristics of scars and the expression of collagen and collagenase-1 (matrix metalloproteinase-1). The results of macroscopic and histologic characteristics revealed a significant difference between scars treated with bFGF and control scars. The expression of collagen in the scars treated with bFGF was decreased, as compared with the scars treated with saline. Further study revealed that bFGF could remarkably enhance expression of matrix metalloproteinase-1. bFGF could improve the quality of wound healing and remarkably alleviate the scar in the rabbit ear model in wound healing, which suggests that bFGF exerted a net negative effecton scar formation in wound healing. The evidence should contribute to a better understanding of the biological activities of bFGF during hypertrophic scar formation.  相似文献   
110.
Transmissible spongiform encephalopathies (TSEs), also termed prion diseases, are fatal neurodegenerative conditions that affect both humans and animals. The transmissibility and fatal nature of TSEs necessitate their rapid and accurate diagnosis. Laser-induced fluorescence (LIF) spectrofluorometry is useful for obtaining measurements on fluorescence-labeled targets with a high degree of sensitivity. In the present study, we applied this technology to the immunological detection of abnormal prion protein, PrPSc, which is a universal diagnostic marker for TSEs. The assay format consists of a magnetic bead-based sandwich immunoassay utilizing a biotin-conjugated capture antibody and a fluorophore-labeled detector antibody. By using one pair of anti-PrP monoclonal antibodies (MAbs), PrPSc in brain homogenates from various experimental and natural TSEs can be easily detected with high specificity. Furthermore, the assay proved to be applicable for the detection of PrPSc in the lymph nodes from deer with TSE. The sensitivity of the assay was shown to be comparable to standard immunoblotting, but has several advantages over conventional tests, in terms of flexibility, simplicity, specificity, and run time. These results provide an important basis for the development of an early diagnostic test with potential for multi-sample analysis.  相似文献   
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