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41.
A 19-year-old, untransfused Melanesian man from Papua New Guinea was admitted to the hospital for repair of an atrial septal defect. His serum contained an alloantibody that reacted strongly on the indirect antiglobulin test and was identified as anti-Ge. Gerbich-negative blood was transfused following urgent surgery. A 51Cr red cell survival study performed 2 weeks after surgery yielded zero survival of Gerbich-positive cells after 24 hours. A monocyte-driven, antibody-dependent, cell-mediated cytotoxicity assay performed on both pretransfusion and posttransfusion serum samples and on concentrated serum showed less than 1 percent specific lysis of Gerbich-positive cells. This did not correlate with the indication of clinical significance predicted by the 51Cr study. Red cell adherence and phagocytosis, not evident in a monocyte monolayer assay using native serum, were demonstrable in 16 percent of monocytes by the use of concentrated serum.  相似文献   
42.

Purpose

To determine if blood type in infertile women relates to the likelihood for live birth (LB) following IVF, and to the etiology for infertility.

Methods

Retrospective study of patients undergoing IVF at two academic centers in the northeast US. Relationships between blood type (A, B, AB, O) and patient characteristics, IVF cycle parameters and LB were assessed utilizing multivariable logistic regression analyses.

Results

In the studied population (n = 626), women with type O were significantly more likely to have baseline FSH > 10 IU/L after adjusting for age, BMI and race (OR 5.09, 95 % CI 1.4–18.7, p = 0.01). Conversely, women with blood type A were significantly more likely to have ovulatory infertility compared to those with blood type O after adjusting for age and BMI (OR 3.2, 95 % CI 1.7–6.2). Blood type B was associated with increased likelihood of live birth (OR 1.9, 95 % CI 1.10–3.41, p = 0.03) after adjusting for factors recognized to impact IVF outcome.

Conclusion

Ovulatory infertility and baseline FSH > 10 IU/L were more prevalent in women with blood type A and O respectively. However, those of blood type B had significantly higher odds for LB compared to other blood types after adjusting for factors recognized to impact on IVF cycle outcome. While underlying mechanisms are unclear, for infertile women, patient’s blood type is seemingly relevant for IVF cycle outcome.  相似文献   
43.
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   
44.
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   
45.
We report the cloning and expression of a cDNA encoding human sterol carrier protein 2 (SCP2). The 1.3-kilobase (kb) cDNA contains an open reading frame which encompasses a 143-amino acid sequence which is 89% identical to the rat SCP2 amino acid sequence. The deduced amino acid sequence of the polypeptide reveals a 20-residue amino-terminal leader sequence in front of the mature polypeptide, which contains a carboxyl-terminal tripeptide (Ala-Lys-Leu) related to the peroxisome targeting sequence. The expressed cDNA in COS-7 cells yields a 15.3-kDa polypeptide and increased amounts of a 13.2-kDa polypeptide, both reacting with a specific rabbit antiserum to rat liver SCP2. The cDNA insert hybridizes with 3.2- and 1.8-kb mRNA species in human liver poly(A)+ RNA. In human fibroblasts and placenta the 1.8-kb mRNA was most abundant. Southern blot analysis suggests either that there are multiple copies of the SCP2 gene in the human genome or that the SCP2 gene is very large. Coexpression of the SCP2 cDNA with expression vectors for cholesterol side-chain cleavage enzyme and adrenodoxin resulted in a 2.5-fold enhancement of progestin synthesis over that obtained with expression of the steroidogenic enzyme system alone. These findings are concordant with the notion that SCP2 plays a role in regulating steroidogenesis, among other possible functions.  相似文献   
46.
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   
47.
48.
Quality of Life Research - To develop two item content-matched, precise, score-level targeted inpatient physical function (PF) short form (SF) measures: one clinician-reported, one...  相似文献   
49.
The application of Escape Theory (Heatherton & Baumeister, 1991 ) to binge eating was studied in a non‐clinical sample of 129 women. Structural equation modelling (SEM) showed a good fit between the Escape Model and the data. Perfectionism strongly predicted aversive self‐awareness which, in turn, predicted negative affect. Negative affect predicted levels of avoidant coping which strongly predicted levels of binge eating. Implications for understanding and treating binge eating are considered. Copyright © 2006 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
50.
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