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21.
The block in differentiation from pro-B to pre-B cells results in a selective defect in the humoral immune response characteristic of human X-linked agammaglobulinemia (XLA). Mutations of Bruton tyrosine kinase (BTK) gene have been identified as the cause of XLA. Mutation detection is the most reliable method for making a definitive diagnosis, except when clinical and laboratory findings are distinctive and coupled with history of X-linked inheritance. To provide a definitive diagnosis to 40 families incorporated in the Argentinian Primary Immunodeficiencies Registry we analysed the BTK gene by SSCP analysis as screening method for XLA, followed by direct sequencing. The molecular defect was localized in 45 patients from 34 unrelated families. From the 34 independent mutations identified, 16 were previously undescribed, 31 were unique mutations, 22 were exonic single nucleotide changes (16 missense and 6 nonsense) and four intronic mutations. Because five families had clinical, immunological and inheritance data sufficient for a definitive diagnosis, our study allowed 37 patients from 29 families previously categorized probable/ possible XLA, have now definitive diagnosis leading to appropriate genetic counseling.  相似文献   
22.
We report the results of reduced-intensity conditioning allogeneic stem cell transplantation (allo-RIC) in patients with advanced Hodgkin lymphoma (HL). Forty patients with relapsed or refractory HL were homogeneously treated with an RIC protocol (fludarabine 150 mg/m(2) intravenously plus melphalan 140 mg/m(2) intravenously) and cyclosporin A and methotrexate as graft-versus-host disease (GVHD) prophylaxis. Twenty-one patients (53%) had received >2 lines of chemotherapy, 23 patients (58%) had received radiotherapy, and 29 patients (73%) had experienced treatment failure with a previous autologous stem cell transplantation. Twenty patients (50%) were allografted in resistant relapse, and 38 patients received hematopoietic cells from an HLA-identical sibling. Five patients (12%) died from early transplant-related mortality (before day +100 after allo-RIC). One-year transplant-related mortality was 25%. Acute GVHD developed in 18 patients (45%). Chronic GVHD developed in 17 (45%) of the 31 evaluable patients. The response rate 3 months after the allo-RIC was 67% (21 [52%] complete remissions and 6 [15%] partial remissions). Eleven patients received donor lymphocyte infusions (DLIs) for disease relapse. The response rate after DLI was 54% (3 complete remissions and 3 partial remissions). Overall survival (OS) and progression-free survival (PFS) were 48% +/- 10% and 32% +/- 10% at 2 years, respectively. Refractoriness to chemotherapy was the only adverse prognostic factor for both OS (63% +/- 12% versus 35% +/- 13%; P = .05) and PFS (55% +/- 16% versus 10% +/- 9%; P = .006). For patients with failure of a prior autologous hematopoietic stem cell transplantation, results were especially good for those who experienced late relapses (>/=12 months: 2-year OS and PFS were 75% +/- 16% and 70% +/- 18%, respectively). These data suggest that allo-RIC is feasible in heavily pretreated HL patients and has an acceptable early transplant-related mortality. Results are better in patients allografted in sensitive disease. Both responses observed after the development of GVHD and DLI may suggest a graft-versus-HL effect. Allo-RIC has to be considered an effective therapeutic approach for patients who have had treatment failure with a previous autologous hematopoietic stem cell transplantation.  相似文献   
23.
Computarized tomography allows proper identification and evaluation of stage in the majority patients with periampullary tumors. However, 30% of peritoneal metastases cannot be seen in image studies. The aim of the present study was to evaluate the role of laparoscopy with laparoscopic ultrasound in the staging process of pancreatic and ampullary tumor. Diagnostic laparoscopy was performed on 20 patients included in the study Mean age was 58.35 +/- 13.4 years. Twelve were males and eight females. In two patients, laparoscopy showed peritoneal metastases and ultrasound did not show extrapancreatic involvement. In five patients, there was vascular invasion without metastases. In three patients, both peritoneal metastases and vascular invasion were found, and in five there was neither vascular invasion nor metastasis. Laparoscopic findings were confirmed in a but one patient. In 14 of the 16 patients In whom peritoneal lavage was performed, microscopic exam showed a sufficient number of cells to make a diagnosis. We concluded that laparoscopy with ultrasound is useful in staging of patients with duodeno-bilio-pancreatic malignancies.  相似文献   
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25.
Prevention Science - Despite the availability of efficacious and effective family-based interventions, such interventions are scarce for sexual minority adolescents, particularly among...  相似文献   
26.
European Journal of Clinical Microbiology & Infectious Diseases - This study determined the carriage rates and antimicrobial resistance (AMR) genes of enterococci from...  相似文献   
27.
28.
Coalescence of the cerebral ventricles with formation of a single forebrain ventricle is described in an unusual case of agenesis of the corpus callosum with dehiscent fornices and severe hydrocephalus. The cerebral hemispheres were fully cleaved. The detached fornices were widely separated from the thalami. The membrana tectoria was retroverted over the midbrain and cerebellum, where it joined the fornices and merged with a curved membranous ependymal dome which, at a great distance, circumvented the thalami as it extended toward the anterior commissure. Other anomalies included arhinencephaly, multiple subependymal heterotopias, and Dandy-Walker malformation. Similar malformations have been described as interhemispheric cysts, as (holo)prosencephaly, or as midline telencephalic dysgenesis. The basic features of prosencephaly and agenesis of the corpus callosum are reviewed and compared to the present case.  相似文献   
29.
PURPOSE: Previous work demonstrates that oleanolic acid (OA), a triterpene widely distributed in plants, shows gastroprotective effect in the ethanol, aspirin and pilorous ligature-induced gastric ulcer in rats as well as in the ethanol/hydrochloric acid-induced ulcer in mice. The aim of this work was to assess the healing effect of OA in the acetic acid-induced chronic gastric ulcer model in rats. METHODS: Chronic gastric lesions were induced in male Sprague-Dawley rats with acetic acid. OA was administered orally during 14 days at 25, 50 and 100 mg/kg per day. Ranitidine (50 mg/kg) and the vehicle were used as controls. The ulcer area (mm2) and the curative ratio (%) were determined. Histological preparations were carried out for comparative purposes. RESULTS: The effect of OA was significantly different as compared to the control reducing the lesion area (in mm2) from 39+/-7 in controls to 17.8+/-1.9 and 9.4+/-1.1 at the doses of 50 and 100 mg/kg, respectively. The curative ratio was 54.5 and 76% for the compound at 50 and 100 mg/kg, while ranitidine at 50 mg/kg reduced the lesion area to 6.9+/-0.8 with a curative ratio of 84%. Mucosal thickness increased from 342 microm in controls to 540 microm in oleanolic acid- (100 mg/kg) and 945 microm in ranitidine-treated animals. Histological examination of the stomach showed regeneration of the lesions. CONCLUSIONS: OA improves healing of chronic gastric lesions in rats. The low toxicity and widespread occurrence of OA in plants suggest a potential for the development of the triterpene or their derivatives as a new antiulcer drug.  相似文献   
30.
Myelodysplastic syndromes and acute myeloid leukemia (AML) are heterogeneous disorders in which conflicting results in apoptosis and multidrug resistance (MDR) have been reported. We have evaluated by multiparameter flow cytometry the expression of apoptosis- (APO2.7, bcl-2, and bax) and MDR-related proteins [P-glycoprotein (P-gp), multidrug resistance protein (MRP), and lung resistance protein (LRP)] specifically on bone marrow (BM) CD34+ cells, and their major CD32-/dim and CD32+ subsets, in de novo AML (n=90), high-risk myelodysplastic syndrome (n=9), and low-risk myelodysplastic syndrome (n=21) patients at diagnosis, and compared with normal BM CD34+ cells (n=6). CD34+ myeloid cells from AML and high-risk myelodysplastic syndrome patients displayed higher expression of bcl-2 (P <0.0001) and lower reactivity for APO2.7 (P=0.002) compared with low-risk myelodysplastic syndrome and normal controls. Similar results applied to the two predefined CD34+ myeloid cell subsets. No significant differences were found in the expression of P-gp, MRP, and LRP between low-risk myelodysplastic syndrome patients and normal BM, but decreased expression of MRP (P <0.03) in AML and high-risk myelodysplastic syndromes and P-gp (P=0.008) in high-risk myelodysplastic syndromes were detected. Hierarchical clustering analysis showed that low-risk myelodysplastic syndrome patients were clustered next to normal BM samples, whereas high-risk myelodysplastic syndromes were clustered together and mixed with the de novo AML patients. In summary, increased resistance to chemotherapy of CD34+ cells from both AML and high-risk myelodysplastic syndromes would be explained more appropriately in terms of an increased antiapoptotic phenotype rather than a MDR phenotype. In low-risk myelodysplastic syndromes abnormally high apoptotic rates would be restricted to the CD34- cell compartments.  相似文献   
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