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81.
Studies on levamisole--induced agranulocytosis   总被引:1,自引:0,他引:1  
Widespread clinical trials of leavo-tetramisole (levamisole) as an immunopotentiating agent in rheumatoid arthritis, metastatic carcinoma, and immunodeficiency states have been complicated by agranulocytosis (AGC) in 2.5%-13% of patients. Other than a relationship with prolonged high dosage, very little is known regarding the pathogenesis of levamisole-induced AGC. Whereas leukoagglutination was negative, fluorochromatic microgranulocytotoxicity (GCY) tests were positive with serum from 10 of 10 acutely neutropenic patients. The antibody was IgM, reacted with 100% of unrelated granulocytes, but not with T or B lymphocytes. Some sera also reacted with monocytes and the myeloid cell line, K-562. Tests for antigen-antibody complexes or cold autoantibodies were negative. Although clinical evidence strongly suggests a haptene (drug) mechanism, in vitro mixing experiments were also negative. An alternative choice parallels the model of aldomet- induced Coombs'-positive hemolytic anemia. Finally, GCY first became positive 2-3 mo prior to the onset of AGC on two patients, suggesting the possibility of identifying those at risk well before the onset of neutropenia.  相似文献   
82.
Reported findings of elevated total calcium (Ca) contents in erythrocytes (RBCs) from patients with beta-thalassemia intermedia (beta-TI) prompted the question of whether the state and transport of Ca in these RBCs are similar to those in sickle cell anemia (SS) RBCs where the increased Ca is compartmentalized in endocytic inside-out vesicles and extracted by exposure of the cells to the Ca ionophore A23187 and a Ca chelator (ethylene glycol tetraacetic acid) and the levels of cytoplasmic free ionized Ca [( Ca2+]i) are normal. We confirmed a high total Ca content of 51 +/- 13 mumol/L RBCs in splenectomized (SPX) beta-TI and 24 +/- 1 mumol/L RBCs in non-SPX beta- TI. Unlike SS RBCs, however, most of the increased Ca was in the lighter, presumably younger beta-TI RBCs, and about half the Ca was not ionophore mobilizable but apparently firmly bound, possibly to remnants of organelles in nucleated and other young RBCs. In the denser RBCs from non-SPX beta-TI, total and extractable Ca amounts were normal. beta-TI RBCs loaded with the Ca chelator Benz 2 showed an initial influx of 45Ca in the normal range, which indicated normal Ca permeability, and near-steady-state levels of [Ca2+]i that were normal (22 +/- 7 nmol/L RBCs in non-SPX beta-TI) or minimally increased (40 +/- 19 nmol/L RBCs in SPX beta-TI). Serial-section electron microscopy of beta-TI ghosts from the denser cell fractions showed more fully enclosed vesicles in non-SPX ghosts than were seen in normal ghosts and many large vesicles and structured, electron-dense material in SPX ghosts. A delayed extrusion of ionophore-preloaded 45Ca only by the SPX beta-TI RBCs together with normal [Ca2+]i suggested compartmentalization of the loaded Ca in these RBCs, perhaps in endocytic inside-out vesicles, and normal Ca pumps. Since beta-TI RBCs show essentially normal levels of [Ca2+]i and normal Ca influx, their high total Ca content should not be associated with any of the deleterious effects observed in vitro with increased levels of [Ca2+]i.  相似文献   
83.
We observed a human immunodeficiency virus (HIV)-infected homosexual male with AIDS related complex (ARC) who had a serum globulin level of 80 g/L. Serum protein electrophoresis revealed a gamma globulin fraction of 40 g/L, of which 50% (20 g/L) was contained within a paraprotein spike, comprised predominantly of IgG kappa. This patient also had high titer anti-HIV antibodies in his serum, which were Western blot reactive at a final dilution of 1:500,000, and recognized gp120env, p66pol, p55gag, p53pol, p41gag, and p24gag. Because paraproteins in the past have been shown to be directed against specific antigens, we purified this patient's paraprotein using a modified high performance liquid chromatography (HPLC)-hydroxylapatite procedure and tested the purified paraprotein for anti-HIV antibody activity. The purified paraprotein retained anti-HIV antibody activity to a final dilution of 1:100,000, and recognized p66pol, p55gag, p53pol, p41gag, and p24gag. The recognition of both "gag" and "pol" gene products suggested that the purified paraprotein might not be monoclonal in origin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that the purified paraprotein contained at least two immunoglobulin light chain species (Mol wt 30 to 33 Kd). Affinity chromatography of the purified paraprotein using a p24- Sepharose 4B matrix separated the "gag" and "pol" antibody activities. Immunoglobulin gene rearrangement analysis of a bone marrow aspirate (which contained 15% plasma cells) failed to reveal a clonal population of immunoglobulin producing cells. We conclude that this patient's paraprotein accounted for most of the anti-HIV activity present in whole serum, and that this paraprotein was not monoclonal in origin.  相似文献   
84.
ObjectiveChildhood food insecurity endangers child development and health outcomes. Food insecurity will grow increasingly common in the economic wake of the coronavirus pandemic and prenatal care represents an early, clinical opportunity to identify families at risk. However, longitudinal relationships between clinically-identified prenatal food insecurity and prematurity, pediatric health care utilization, and postnatal social needs have not been described.MethodsWe examined longitudinal data from mother-child dyads who received prenatal and pediatric care and social needs screening at a large academically-affiliated safety net medical center between October 2018 and July 2019. Associations among household food insecurity and premature birth, pediatric inpatient and outpatient utilization, missed immunizations, and postnatal social needs were estimated using adjusted regression.ResultsAmong the 268 mothers, those who experienced prenatal household food insecurity had 3 times higher odds of having a child born prematurely (95% confidence interval [CI] 1.0–8.9, P = .05) and had children with higher inpatient hospitalizations (incidence rate ratio [IRR] 2.4, 95% CI 1.0–5.6, P = .04) and missed immunizations (IRR 3.4, 95% CI 1.1–10.3, P = .03) in the first 6 months of the child's life. These mothers also had higher odds of having any social needs in the pediatric setting (odds ratio 3.4; 95% CI 1.5–8.0, P = .004).ConclusionsPrenatal household food insecurity was linked to future adverse perinatal and pediatric outcomes in low-income mother-child dyads. Food insecurity identifies children at social and medical risk, providing an early clinical opportunity to intervene.  相似文献   
85.
86.
BackgroundTreatment of early-stage non-small cell lung cancer (NSCLC) is rapidly evolving. When introducing novelties, real-life data on effectiveness of currently used treatment strategies are needed. The present study evaluated outcomes of stage I–IIIA NSCLC patients treated with upfront radical surgery in everyday clinical practice, between 2010–2017.Patients and methodsData of 539 consecutive patients were retrieved from a prospective hospital-based registry. All diagnostic, treatment and follow-up procedures were performed at the same thoracic oncology centre according to the valid guidelines. The primary outcome was overall survival (OS) analysed by clinical(c) and pathological(p) TNM (tumour, node, metastases) stage. The impact of clinicopathological characteristics on OS was evaluated using univariable (UVA) and multivariable regression analysis (MVA).ResultsWith a median follow-up of 53.9 months, median OS and 5-year OS rate in the overall population were 90.4 months and 64.4%. Five-year OS rates by pTNM stage I, II and IIIA were 70.2%, 60.21%, and 49.9%, respectively. Both cTNM and pTNM stages were associated with OS; but only pTNM retained its independent prognostic value (p = 0.003) in MVA. Agreement between cTNM and pTNM was 69.0%. Next to pTNM, age (p = 0.001) and gender (p = 0.004) retained their independent prognostic value for OS.ConclusionsThe study showed favourable outcomes of resectable stage I–IIIA NSCLC treated with upfront surgery in real-life. Relatively low agreement between cTNM and pTNM stages and independent prognostic value of only pTNM, observed in real-life data, suggest that surgery remains the most accurate provider of the anatomical stage of disease and important upfront therapy.Key words: resectable NSCLC, upfront surgery, real-life data, overall survival, prognostic factors  相似文献   
87.
Intravenous therapy with the anti-CD20 antibody Rituximab has been recently approved for the treatment of CD20 positive non-Hodgkin's lymphoma (NHL) in adults but not in children. The authors present the benefits of its application for mediastinal NHL CD 20+ with a local extension into the lung of a 10-year-old-girl. Receiving the chemotherapy according to study NHL-BFM-95 for high-risk lymphoma the girl did not reach complete remission. Before the last chemotherapy block was started, a computed tomography scan of the thorax showed residue in the right lung. Twenty-five days after the last chemotherapy she received Rituximab at a dose of 375 mg/m 2 by intravenous infusion once a week for a total of four doses without the adverse reactions. Complete remission was achieved. The patient was high risk with lung involvement of lymphoma suggesting a pure prognosis. The results suggest that Rituximab may improve the outcome in high-risk patients and appeared to be safe and effective in children also.  相似文献   
88.
Objectives. To determine whether the positive fraction of systematic sextant biopsies contributes to the prediction of serologic relapse after radical prostatectomy.Methods. A retrospective review of patients who underwent transrectal ultrasound-guided systematic sextant biopsy and radical prostatectomy was performed. No patients received neoadjuvant or adjuvant therapy. The relationship between the positive fraction of systematic biopsies and risk of prostate-specific antigen recurrence was assessed with Kaplan-Meier and multivariate analyses.Results. Patients with three or fewer positive sextant biopsies were at a significantly lower risk of relapse after radical prostatectomy than patients with four or more positive biopsies. Tumor grade and systematic biopsy results were the most powerful predictors of serologic relapse.Conclusions. The positive fraction of systematic biopsies contributes to the prediction of risk of relapse after radical prostatectomy.  相似文献   
89.
Oral forces applied to human teeth during biting and mastication are normally described in the literature only in terms of their axial components. The purpose of this study was to fully determine the spatial characteristics of the oral resultant force – its normal and tangential components - for a given individual. A load cell was especially manufactured to measure oral force and was temporarily implanted as a prosthetic device in the dental arch of a volunteer, replacing his missing upper first molar. The mastication and occlusion tests were carried out in such a way the cell should withstand the loads applied to the molar, and its state of strain was recorded by strain gauges attached to it. Based on the results of these tests and using balance equations, normal and tangential components of the resultant oral force were determined. For direct occlusion, without interposition any obstacle between cusps, a peak normal force of 135 N was recorded simultaneously to a tangential force of 44 N. For mastication of biscuits, a peak normal force of 133 N and a tangential force of 39 N were obtained.  相似文献   
90.
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