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41.
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity.  相似文献   
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Antithrombin III (AT-III) was studied in a thrombophilic family with an abnormal AT-III molecule (antithrombin III Budapest) using a modified crossed immunoelectrophoresis technique, gel filtration, 'rocket' immunoelectrophoresis and a heparin cofactor assay. When agarose was applied in the first phase of the crossed immunoelectrophoresis, the normal and the pathological AT-III revealed identical electrophoretic mobility. However, when heparin was mixed with agarose in the first phase of electrophoresis, the propositus' plasma displayed a different AT-III pattern from normal plasma. His plasma contained the first component of the normal plasma (Immune Antithrombin III1, IAT-III) in a concentration of only 5% of normal, and a protein in high concentration which although immunoreactive to AT-III antisera, had an electrophoretic mobility similar (but not identical to that of IAT-III2. This abnormal protein had no heparin cofactor activity and a molecular size greater than normal plasma AT-III. Unlike AT-III, the addition of heparin did not change the molecular size of the pathogic AT-III molecule significantly. The abnormal protein was present in lower concentrations in the patient's children and at the time of study they had no clinical or laboratory evidence of intravascular coagulation.  相似文献   
43.
OBJECTIVE: Tension development is often incoordinate in the hypertrophic left ventricle (LV). The present study aimed to elucidate the possible effects of incoordination on standard LV force-velocity relations in patients with aortic stenosis (AS). DESIGN: Prospective study during aortic valve replacement with transoesophageal cross sectionally guided M mode echocardiogram, combined with high-fidelity LV pressure recorded by pressure transducer tip catheter, and thermodilution cardiac output. SETTING: Tertiary cardiac referral centre. PATIENTS: 37 patients (mean (SD) age 63 (12)) years were studied before and 20 hours after aortic valve replacement. MAIN OUTCOME MEASURES: LV function was assessed regionally by peak velocity of circumferential fibre shortening (peak Vcf), mean systolic wall stress, and peak myocardial power; and globally by LV stroke work index. LV coordination was quantified as cycle efficiency, derived from LV pressure-dimension loop (lower normal limit > or = 76%). RESULTS: 22 patients with a coordinate LV had significantly higher peak Vcf (1.85 (0.47) v 1.46 (0.64) s-1) peak myocardial power (20.8 (8.5) v 12.0 (6.1) mW.cm-3) and global stroke work index (440 (155) v 325 (150) mJ.m-2) than those of 15 patients with an incoordinate ventricle, all P < 0.05; though there was no significant difference in LV end diastolic dimension, mean systolic wall stress, LV mass index, or the incidence of coronary artery disease (P > 0.05, respectively). Furthermore, when contraction was coordinate, mean systolic circumferential wall stress correlated inversely with peak Vcf (r = - 0.71) and positively with peak myocardial power (r = 0.83), both P < 0.01. When contraction was incoordinate, these correlations did not apply; instead peak Vcf (r = 0.65) and peak myocardial power (r = 0.73) both correlated positively with cycle efficiency (P < 0.02 and 0.01, respectively). By 20 hours after surgery, values of cycle efficiency, peak Vcf, and myocardial power were indistinguishable in the previously coordinate and incoordinate groups. CONCLUSIONS: In aortic stenosis, incoordination causes a fall in LV peak Vcf proportional to the increase in systolic wall stress, and thus modifies the standard LV force-velocity relation to mimic depressed contractility. However, incoordination and subsequent ventricular dysfunction were largely reversible once the aortic stenosis had been relieved.  相似文献   
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The grey zone (GZ; 45–54 CGG repeats in the FMR1 gene) is considered a normal allele; however, several studies have found a high frequency of GZ in movement disordered populations. Here, we describe neurological features of fragile X‐associated tremor/ataxia syndrome (FXTAS) in two carriers of GZ alleles, although FXTAS has been defined as occurring only in premutation carriers (55–200 CGG repeats). Both patients had family members who had premutation and were diagnosed with FXTAS. The presence of relatively high GZ alleles with elevated fragile X mental retardation 1 mRNA (FMR1‐mRNA) combined with a family history of FXTAS that may represent a facilitating genetic background for FXTAS are the factors that led to the presence of FXTAS in these individuals with a GZ allele. Further research into clinical involvement of GZ alleles is recommended and the definition of FXTAS may require revision.  相似文献   
47.
BackgroundIliotibial Band Syndrome (ITBS) is a common clinical condition likely caused by abnormal compressive forces to the iliotibial band (ITB). Stretching interventions are common in ITBS treatment and may predominantly affect tensor fascia latae (TFL). Another ITBS treatment is foam rolling, which may more directly affect the ITB. Shear wave ultrasound elastography (SWUE) measures real-time soft tissue stiffness, allowing tissue changes to be measured and compared.PurposeTo examine effects of foam rolling and iliotibial complex stretching on ITB stiffness at 0˚ and 10˚ of hip adduction and hip adduction passive range of motion (PROM).Study DesignRandomized controlled trial.MethodsData from 11 males (age = 30.5 ± 9.0 years, Body Mass Index (BMI) = 27.8 ± 4.0) and 19 females (age = 23.5 ± 4.9, BMI = 23.2 ± 2.1) were analyzed for this study. Subjects were randomly assigned to one of three groups: control, stretching, and foam rolling. Shear wave ultrasound elastography measurements included ITB Young’s modulus at the mid-thigh, the distal femur and the TFL muscle belly. ITB-to-femur depth was measured at mid-thigh level. Hip adduction PROM was measured from digital images taken during the movement.ResultsNo significant interactions or main effects were found for group or time differences in ITB Young’s modulus at the three measured locations. The ITB stiffness at the mid-thigh and distal femur increased with 10° adduction, but TFL stiffness did not increase. A main effect for adduction PROM was observed, where PROM increased 0.8˚ post-treatment (p = 0.02).ConclusionA single episode of stretching and foam rolling does not affect short-term ITB stiffness. The lack of ITB stiffness changes may be from an inadequate intervention stimulus or indicate that the interventions have no impact on ITB stiffness.Levels of Evidence1b  相似文献   
48.
Escherichia coli encodes three SOS-induced DNA polymerases: pol II, pol IV, and pol V. We show here that each of these polymerases confers a competitive fitness advantage during the stationary phase of the bacterial life cycle, in the absence of external DNA-damaging agents known to induce the SOS response. When grown individually, wild-type and SOS pol mutants exhibit indistinguishable temporal growth and death patterns. In contrast, when grown in competition with wild-type E. coli, mutants lacking one or more SOS polymerase suffer a severe reduction in fitness. These mutants also fail to express the "growth advantage in stationary phase" phenotype as do wild-type strains, instead expressing two additional new types of "growth advantage in stationary phase" phenotype. These polymerases contribute to survival by providing essential functions to ensure replication of the chromosome and by generating genetic diversity.  相似文献   
49.
CD40 was originally described as a B-cell-restricted antigen and was subsequently found to be a member of the tumor necrosis factor (TNF) receptor superfamily. CD40 is also expressed on dendritic cells, thymic epithelium, monocytes, and some carcinoma cell lines, and plays a critical role in cell contact-dependent activation. Primary and cultured Hodgkin and Reed-Sternberg (H-RS) cells, the presumed malignant cells of Hodgkin's disease (HD); were found to express high levels of cell surface CD40. We found that recombinant CD40 ligand (CD40L) induced interleukin-8 (IL-8) secretion and enhanced IL-6, TNF, and lymphotoxin-alpha (LT-alpha/TNF-beta) release from cultured H-RS cells. These cytokines play a significant role in the clinical presentation and pathology of HD, a tumor of cytokine-producing cells. CD40L had no mitogenic activity for HD-derived cell lines. In contrast, CD40L enhanced expression of costimulatory molecules intracellular adhesion molecule-T and B7-1 on cultured H-RS cells, both of which are overexpressed on primary H-RS cells. In addition, CD40L induced a 40% to 60% reduction of the expression of the HD-associated CD30 antigen, another member of the TNF receptor superfamily. Primary and cultured H- RS cells express not only CD30, but also CD40. CD40L has pleiotropic biologic activities on H-RS cells, and the CD40-CD40L interaction might be a critical element in the deregulated cytokine network and cell contact-dependent activation cascade typical for HD.  相似文献   
50.
Patients who have undergone allogeneic bone marrow transplantation (allo-BMT) are susceptible to a variety of opportunistic infectious complications in the months to years after engraftment. Impaired in vitro T-cell functions have been documented in these patients, and these T-cell dysfunctions contribute to the prolonged immune deficiency after allo-BMT. In the present study, we examined the expression of CD26 as well as the reconstitution of CD26-mediated T-cell costimulation via the CD3 and CD2 pathways at various times in patients aged greater than 18 years after CD6-positive, T-cell depleted allo- BMT. We found that the percentage of CD26- and CD3-positive cells, as well as the levels of expression of both antigens, was lower than in normal controls during the first 4 months after CD6-depleted allo-BMT. Subsequently, the amount of lymphocytes expressing CD3 and CD26 and the quantitative surface expression of CD3 and CD26 were not significantly different in patients and normal controls. Functional studies showed that CD26-mediated T-cell proliferation via the CD3 pathway was considerably improved and almost reached normal levels by 1 year, whereas recovery of CD26-mediated T-cell proliferation via the CD2 pathway was delayed for at least 2 years after CD6-depleted allo-BMT. As CD26 involvement in the regulation of human thymocyte activation is restricted preferentially to the CD3 pathway--unlike its involvement with both CD3 and CD2 pathways of peripheral T cells--our results suggest that the different effects of CD26-mediated costimulation via the CD3 and CD2 pathways after CD6-depleted allo-BMT may be a reflection of peripheral T-cell immaturity in those individuals, similar to that seen in mature medullary thymocytes or cord T lymphocytes.  相似文献   
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