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61.
Nielsen  OJ; Schuster  SJ; Kaufman  R; Erslev  AJ; Caro  J 《Blood》1987,70(6):1904-1909
Production of immuno and biologically active erythropoietin was documented to occur in the human hepatoblastoma cell line HepG-2. The expression of the erythropoietin gene was further verified by Northern blot analysis using a single stranded RNA probe. In vitro studies showed that erythropoietin production by these cells was not stimulated by hypoxia or cobalt chloride, but was related to the proliferative activity of the cells in culture. In addition it was found that the secretion of erythropoietin was almost completely abrogated by tunicamycin, an inhibitor of N-linked glycosylation. This effect of tunicamycin was also observed in a permanently transfected cell line that secretes erythropoietin in large quantities.  相似文献   
62.
An alternative extrinsic pathway of human blood coagulation   总被引:7,自引:0,他引:7  
Marlar  RA; Kleiss  AJ; Griffin  JH 《Blood》1982,60(6):1353-1358
To study the interrelationships of the major human coagulation pathways, factor X activation in normal and various deficient human plasmas was evaluated when clotting was triggered by dilute rabbit or human thromboplastin. Various dilutions of thromboplastin were added to plasma samples containing 3H-labeled factor X, and the time course of factor X activation was determined. At a 1/250 dilution of rabbit brain thromboplastin the rate of factor X activation in factor VIII or factor IX deficient plasma was only 10% of the activation rate seen for normal or factor XI deficient plasma. Reconstitution of the deficient plasmas with factors VIII or IX, respectively, restored normal factor X activation. Similar results were obtained when various dilutions of human thromboplastin replaced the rabbit thromboplastin. From these experiments, it is inferred that normal activation of factor X in plasma due to dilute thromboplastin requires factors VII, IX and VIII. An alternative extrinsic pathway that involves factors VII, IX, and VIII may be a major physiologic extrinsic pathway, and this pathway may help to explain the clinical observations of bleeding diatheses in patients deficient in factors IX or VIII.  相似文献   
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Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study.  相似文献   
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Factor V deficiency has been identified in 8 of 8 patients 7--20 yr of age, with Philadelphia-positive (Ph1+) chronic myelogenous leukemia (CML). In these 8 patients, factor V deficiency was not due to hepatic dysfunction, factor V inhibitors, or disseminated intravascular coagulation. In 3 patients, factor V activity rose 10%--12% (0.10--0.12 U/ml) after the infusion of 28--31 ml/kg body weight of fresh frozen plasma (FFP). The rise persisted less than 14 hr. The mean measured postinfusion rise in factor V was 18% of the expected rise calculated from the volume of FFP infused in the patients' plasma volume. In 4 patients, a small transient rise in factor V activity occurred after splenectomy or plateletpheresis. Factor V deficiency was completely corrected after a marked reduction in bone marrow cellularity in 2 patients with Ph1+ CML treated with extensive chemotherapy, total body irradiation, and bone marrow transplantation. Factor V deficiency was retrospectively observed in 6 of 20 patients, ages 20--80 yr, with Ph1+ CML and 3 of 6 patients with other myeloproliferative disorders. The factor V deficiency appears to be associated with the large myeloid- megakaryocytic cell mass characteristic of CML and other myeloproliferative disorders.  相似文献   
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Introduction

Single incision laparoscopic surgery (SILS) is established in many procedures but not in bariatric surgery. One explanation may be that SILS is technically demanding in morbidly obese patients. This report describes our technique and experience with single incision laparoscopic adjustable gastric banding (SILAGB).

Methods

Prospective data collection was performed on consecutive obese patients who underwent SILAGB between November 2009 and February 2011. A single 3cm transverse incision in the right upper quadrant was used for a Covidien SILS multichannel access port. The technique is described with a standard pars flaccida approach and the ‘tips and tricks’ needed for a wide range of candidates using standard laparoscopic equipment.

Results

A total of 29 patients (27 female) with a median body mass index of 41kg/m2 (range: 35–52kg/m2) and median age of 44 years (range: 22–57 years) underwent SILAGB. There were no ‘conversions’ to a standard laparoscopic technique. Two cases required the addition of one single 5mm port. The only complications were two postoperative wound infections (one with a port site infection requiring replacement of the port) and one faulty band requiring replacement. There were therefore two returns to theatre and no 30-day deaths. All patients were discharged on the first postoperative day. In this series, operative times reduced significantly to be comparable with the conventional laparoscopic approach.

Conclusions

SILAGB is safe and feasible in the morbidly obese. Proficiency in this technique using conventional laparoscopic equipment can be achieved with a short learning curve.  相似文献   
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