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971.
Kamel AM Shaker HM GadAllah FH Hamza MR Mansour O El Hattab OH Moussa HS 《Cancer Genetics and Cytogenetics》2000,122(2):110-115
Molecular characterization is considered a part of the routine work-up of chronic myeloid leukemia (CML) cases. Southern blot analysis using the universal BCR (UBCR) probe on BglII-digested DNA samples is the most commonly used technique, while employing the human 3' bcr probe (PR-1) is usually considered a complementary tool. In this study, we tried to develop a simple and economic strategy for molecular characterization of CML using the 3' probe as it has been shown to be the one capable of locating the breakpoint site. Seventy-eight cases of CML were studied. Molecular analysis was performed using the Southern blot technique. DNA was digested with Bam HI, BglII, EcoRI, and XbaI. Hybridization was performed using the human 3' bcr (PR-1) probe. BamHI and BglII could differentiate fragment 1 (F1) showing rearrangement (R) with Bam HI and germline configuration (G) with BglII; F2/3 showing R with both, and F4 showing R with BamHI and G with BglII. F2/3 cases were further divided by HindIII enzyme into F2 showing (G) and F3 showing (R). Fragment 0 showed G with both, but R with EcoRI and/or XbaI, while 3' deletion gave G with all four enzymes. Our results showed a relative incidence of 6.4% for F0, 20.5% for F1, 32.1% for F2, 19.2% for F3, 15.4% for F4, and 6.4% for 3' deletion. Sixty cases were evaluated clinically and hematologically and were followed up for disease evolution and survival. They included 32 cases in early chronic phase, 24 in late chronic phase, two in acceleration, and two in blastic crisis. No significant correlation was encountered between the breakpoint site and any of the clinical and hematological data except those patients with 3' deletion who showed a very short survival. The study emphasizes Southern blotting as the method of choice for molecular characterization of CML and offers a simple and economic strategy for diagnosis and determination of breakpoint fragment. 相似文献
972.
973.
El Quessar A Jroundi L Tizniti S Cissé M Chakir N El Hassani MR Benchaâboun H Jiddane M 《Journal de radiologie》2001,82(8):917-921
PURPOSE: Hydatidosis affects the bone in 0.5 to 2% of cases, with 44% of these cases involving the spine. We report 8 cases of vertebral involvement evaluated by CT and/or MRI. Materials and Methods. This retrospective study from January 1996 to August 2000 included seven patients (5 men and 3 women) aged between 28 and 65 years old. The mean age was 45 years old. Five patients underwent CT scan (one by CT-myelography). MRI was available in 4 cases. RESULTS: Imaging showed multicystic bony lesions. Thoracic involvement was present in 4 cases, lumbar involvement in 2 cases, and sacral involvement in 2 cases. The process involved 2 adjacent vertebrae in 4 cases at the thoracic and lumbar levels and the entire sacrum in the other cases. Only one case of vertebral collapse was noted, but extension into the spinal canal was noted in all cases. Other sites of involvement were also noted, especially in adjacent soft tissues, liver and spleen. CONCLUSION: The presence of multicystic vertebral lesions with involvement of adjacent soft tissues and/or distant organs should raise the possibility of spinal hydatidosis in endemic countries. 相似文献
974.
High-performance liquid chromatographic method for the determination of benzodiazepines in plasma or serum using the column-switching technique 总被引:2,自引:0,他引:2
El Mahjoub A Staub C 《Journal of chromatography. B, Biomedical sciences and applications》2000,742(2):381-390
A column-switching high-performance liquid chromatographic method for the simultaneous determination of five frequently prescribed benzodiazepines: clonazepam, diazepam, flunitrazepam, midazolam and oxazepam was developed. A 50-microl plasma sample was directly injected into a BioTrap 500 MS (hydrophobic polymer) column. After a washing step with a mixture of phosphate buffer and acetonitrile, the retained benzodiazepines were back-flushed into a reversed-phase (LiChrospher Select B C8) column with a mobile phase of acetonitrile-phosphate buffer. The method showed excellent linearity from 50 to 1000 ng/ml for clonazepam, flunitrazepam and midazolam and from 50 to 5000 ng/ml for diazepam and oxazepam. The recoveries were around 98% for all the benzodiazepines studied. The relative standard deviation for between-and within-day assay was <20% for low concentrations close to the values of the limit of quantification and <4% for high concentrations. The procedure described is relatively simple and rapid because no off-line manipulation of the sample is required: the total analysis time is approximately 30 min. 相似文献
975.
El Bouhmadi A Laffargue F Raspal N Brun JF 《Clinical hemorheology and microcirculation》2000,22(2):99-106
Since oral contraceptives (OC) are known to impair blood fluidity and to increase the risk of venous and arterial thrombosis, while acetylsalicylic acid (ASA) decreases the thrombotic risk and modifies some rheologic parameters, we compared the hemorheologic effects of ASA on blood rheology between women treated by OC and women who never received this medication. 25 women under OC were compared to 25 matched women who had never used OC. Blood viscosity (MT90 viscometer) and RBC aggregation (Myrenne aggregometer and AFFIBIO erythroaggregometer) were measured before and 1 hr after women received per os 100 mg ASA, after an overnight fast. The only significant difference between women under OC and controls was an increased RBC aggregation ('M' index +28%, p < 0.04; Affibio aggregation time -21%, p < 0.03). On the whole sample of 50 women as well as in the subgroup of women under OC, ASA decreased RBC partial disaggregation threshold (-1.7%, p < 0.01). These results confirm that RBC aggregation is increased under OC and suggest that 100 mg ASA acutely induces a partial reversal of this RBC hyperaggregation. 相似文献
976.
Le Coz CJ Coninx D Van Rengen A El Aboubi S Ducombs G Benz MH Boursier S Avenel-Audran M Verret JL Erikstam U Bruze M Goossens A 《Contact dermatitis》1999,40(2):77-83
Since November 1997, 14 successive cases of occupational contact dermatitis were observed in 13 laboratory technicians and 1 physician, working in a genetics laboratory in Leuven (Belgium) in 3 laboratories of bacteriology in Strasbourg, Montbeliard and Angers, and in the laboratory of hematology in Bordeaux (France). The dermatitis, located on the hands, forearms and face, relapsed after each exposure to an immersion oil for microscopy. Patch tests performed in 10 patients were positive to epoxy resin (ER) in the European standard series (10/10 patients) and to newly formulated Leica immersion oil (7/7), 1 patient testing negatively with the former oil. A breakdown performed in 2 patients with the oil's ingredients confirmed sensitization to liquid modified ER components, contained at >80% concentration in the oil. The presence of DGEBA was demonstrated by HPLC analysis at a +/-30% rate. Although the safety data sheet indicated a revision of the formula, nobody was alerted to the risk of sensitization and the need for skin protection. ERs, as a source of occupational allergy, can provoke epidemics of contact dermatitis in industry. This report of epidemic contact dermatitis from ERs, used for their optical properties in an immersion oil for microscopy, emphasizes the need for perpetual vigilance in occupational medicine and the usefulness of multicentre contacts in dermato-allergology. 相似文献
977.
Lê MG Mathieu MC Douc-Rasy S Le Bihan ML Adb El All H Spielmann M Riou G 《International journal of cancer. Journal international du cancer》1999,84(6):562-567
Apoptosis is an important physiological process controlled by multiple genes, including c-myc, p53 and bcl-2, and its inhibition may lead to the development of human cancers. In this study, we analyzed expression of the c-myc gene using Northern blot and of the p53 and bcl-2 proteins by immuno-histochemistry in 175 breast tumor specimens obtained from patients with operable breast cancer. We evaluated the relation between expression of these 3 genes and (i) the main usual prognostic factors (tumor size, histo-prognostic grade, hormone receptors and number of positive nodes); (ii) the risk of death and relapse, taking into account these 4 factors, after a mean period of follow-up of 9.5 years (SD 2 years). Over-expression of c-myc, p53 and bcl-2 was observed in 35%, 23% and 63% of tumors, respectively. Over-expression of c-myc was strongly linked to the number of positive nodes (p = 0.0005). p53 protein expression was associated with both high-grade (p = 0.0001) and hormone receptor-negative (p = 0.0001) tumors. In contrast, bcl-2 protein over-expression was associated with the main favorable prognostic factors and, more particularly, with hormone receptor-positive tumors (p = 0.0001). Multivariate analysis, using the Cox model, showed that only 2 factors were independently linked to the risk of death: number of positive nodes, which increased the risk (p = 0.0001), and bcl-2 protein over-expression, which decreased the risk (p = 0.008). When bcl-2 over-expression was studied in relation to nodal status, hormone receptor status and chemo- and hormone therapy, no significant difference was observed between different subgroups of patients. bcl-2 expression was also associated with a significantly lower risk of distant metastasis (p = 0.04). In conclusion, bcl-2 expression characterizes a particular phenotype of breast cancer with a favorable prognosis, and it may therefore be used as a marker of long-term survival. Int. J. Cancer (Pred. Oncol.) 84:562-567, 1999. 相似文献
978.
Fracchia A Ubbiali A El Bitar O Pacetti M Sommariva E Arreghini M Longhini E Bonalumi GP 《Oncology》1999,56(3):181-188
OBJECTIVES: To assess the diagnostic value of bronchoalveolar lavage fluid (BALF) ferritin as a lung tumor marker by comparing serum and BALF ferritin concentrations in patients with peripheral lung cancer versus control subjects with benign lung disease, and to examine the theory of ferritin compartmentalization around the tumor area by comparing ferritin concentrations in serum and bilateral (affected and unaffected side) BALF in cancer patients. METHODS: Four groups of patients were investigated: 10 control nonsmokers, 10 control smokers, 10 smokers with chronic obstructive pulmonary disease (COPD), and 22 patients with primary bronchogenic carcinoma. A bronchoalveolar lavage (BAL) was performed in all subjects (both sides in 13 oncological patients, one side in the others) and samples of BALF and blood were submitted to biochemical analysis. RESULTS: As a lung tumor marker, BALF ferritin showed 54% sensitivity and 93% specificity and serum ferritin 22% sensitivity and 93% specificity. A significant difference was observed between the two sides in the cancer patients (p = 0.033), and between BALF ferritin from the affected side and COPD patients (p = 0.025). Greater differences were obtained when BALF ferritin in the affected side of cancer patients was compared with values in both control nonsmokers (p < 0.0001) and control smokers (p < 0.001). CONCLUSIONS: These findings seem to confirm the relative diagnostic value of BALF ferritin as a lung tumor marker and the theory of ferritin compartmentalization. However, further studies are required to clarify the relations between iron and ferritin on the one hand and inflammation, tumorigenesis and host response on the other. 相似文献
979.
980.