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51.
The responses of lymphocytes to Epstein-Barr virus (EBV) were investigated in five patients with common variable immunodeficiency (CVID). In three patients with CVID in whom the percentages of CD20+ cells and CD21/EBV receptor+ cells were markedly reduced, PBMCs and/or B cells did not respond (or scarcely) to EBV. This may be due to reduction of B cell numbers or reduction of EBV receptor bearing cells. In one patient with CVID in whom the percentages of CD20+ cells and CD21/EBV receptor+ cells were mildly reduced, PBMCs and/or B cells responded well to EBV and secreted immunoglobulin (Ig). This result shows that the patient's B cells with EBV receptors are sufficient to transduct EBV-signals into the nucleus and to respond to EBV. In another patient in whom the percentages of CD20+ cells and CD21/EBV receptor+ cells were not reduced, PBMCs mildly responded to EBV and scarcely secreted Ig. This result shows that the patient's B cells with EBV receptors may not be sufficient to transduct EBV-signals into the nucleus and to respond to EBV.  相似文献   
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Knowing a patient’s cardiac output (CO) could contribute to a safe, optimized hemodynamic control during surgery. Precise CO measurements can serve as a guide for resuscitation therapy, catecholamine use, differential diagnosis, and intervention during a hemodynamic crisis. Despite its invasiveness and intermittent nature, the thermodilution technique via a pulmonary artery catheter (PAC) remains the clinical gold standard for CO measurements. LiDCOrapid? (LiDCO, London, UK) and FloTrac/Vigileo? (Edwards Lifesciences, Irvine, CA) are less invasive continuous CO monitors that use arterial waveform analysis. Their calculations are based on arterial waveform characteristics and do not require calibration. Here, we evaluated LiDCOrapid? and FloTrac/Vigileo? during off-pump coronary artery bypass graft (OPCAB) and living-donor liver transplantation (LDLT) surgery. This observational, single-center study included 21 patients (11 OPCAB and 10 LDLT). We performed simultaneous measurements of CO at fixed sampling points during surgery using both devices (LiDCOrapid? version 1.04-b222 and FloTrac/Vigileo? version 3.02). The thermodilution technique via a PAC was used to obtain the benchmark data. LiDCOrapid? and FloTrac/Vigileo? were used in an uncalibrated fashion. We analyzed the measured cardiac index using a Bland–Altman analysis (the method of variance estimates recovery), a polar plot method (half-moon method), a 4-quadrant plot and compared the widths of the limits of agreement (LOA) using an F test. One OPCAB patient was excluded because of the use of an intra-aortic balloon pumping during surgery, and 20 patients (10 OPCAB and 10 LDLT) were ultimately analyzed. We obtained 149 triplet measurements with a wide range of cardiac index. For the FloTrac/Vigileo?, the bias and percentage error were ?0.44 L/min/m2 and 74.4 %. For the LiDCOrapid?, the bias and percentage error were ?0.38 L/min/m2 and 53.5 %. The polar plot method showed an angular bias (FloTrac/Vigileo? vs. LiDCOrapid?: 6.6° vs. 5.8°, respectively) and radial limits of agreement (?63.9 to 77.1 vs. ?41.6 to 53.1). A 4-quadrant plot was used to obtain concordance rates (FloTrac/Vigileo? vs. PAC and LiDCOrapid? vs. PAC: 84.0 and 92.4 %, respectively). We could compare CO measurement devices across broad ranges of CO and SVR using LDLT and OPCAB surgical patients. An F test revealed no significant difference in the widths of the LoA for both devices when sample sizes capable of detecting a more than two-fold difference were used. We found that both devices tended to underestimate the calculated CIs when the CIs were relatively high. These proportional bias produced large percentage errors in the present study.  相似文献   
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In a patient with holoprosencephaly, partial seizures had various initial ictal symptoms, and ictal EEGs showed epileptogenic foci in the right and left brain. Partial seizures did not culminate in secondary generalized tonic-clonic convulsions. Characteristic malformed structures contribute to the absence of secondary generalization and the presence of Jacksonian-type propagation.  相似文献   
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OBJECTIVE: A randomized controlled trial was conducted to clarify the effectiveness of intraoperative blood salvage in reducing blood loss. BACKGROUND: Although reduction of central venous pressure (CVP) is thought to decrease blood loss during liver resection, no consistently effective and safe method for obtaining the desired reduction of CVP has been established. METHODS: Living liver donors scheduled to undergo liver graft procurement were randomly assigned to a blood salvage group, in which a blood volume equal to approximately 0.7% of the patient's body weight was collected before the liver transection, or a control group. The surgeons were blinded to the randomization results. The primary outcome measure was blood loss during liver parenchymal division. A multivariate analysis was also performed. RESULTS: Seventy-nine donors were allocated intraoperatively to the blood salvage group (n = 40) or the control group (n = 39). The amount of blood loss during liver transection was significantly smaller in the blood salvage group than in the control group (median loss during transection, 140 mL vs. 230 mL, P = 0.034). The CVP at the beginning of the liver parenchymal division was significantly lower in the blood salvage group than in the control group (median, 5 cm H2O vs. 6 cm H2O, P = 0.005). The results of a multivariate analysis revealed that intraoperative blood salvage offered the advantage of reduced blood loss during liver parenchymal division (adjusted OR, 0.31; 95% CI, 0.11-0.85, P = 0.025). CONCLUSION: Modest intraoperative blood salvage significantly and safely reduced blood loss during hepatic parenchymal transection.  相似文献   
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Many reports have shown that expression of the c-myc protooncogene represents an early event of lymphocyte activation. Calcium influx and activation of protein kinase C synergistically bypass the early signal transduction of lymphocyte activation. In this study, the c-myc message of B cells or B cell lines stimulated by 12-o-tetradecanoylphorbol-13-acetate (TPA), A23187, Staphylococcus aureus Cowan I (SAC), or anti-mu was not expressed or was poorly expressed in common variable immunodeficiency (CVID) patients whose B cells did not differentiate or only poorly differentiated to SAC plus recombinant interleukin 2, whereas the c-myc message of 1 CVID patient's B cells that differentiated well in IgM secretion to SAC plus recombinant interleukin 2 was well expressed when stimulated by TPA, A23187, SAC, or anti-mu. These results suggest that an abnormality exists in the early signal transduction process on some CVID patients' B cells and that it may be in the bypass by calcium influx and direct activation of protein kinase C.  相似文献   
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Complementary DNAs encoding the precursor of human hepatic mitochondrial acetoacetyl-CoA thiolase (T2) (EC 2.3.1.9) were cloned and sequenced. The cDNA inserts in these clones were 1,518 bases in length when overlapped, and encoded the 427-amino acid precursor of this enzyme (45,199 mol wt). This amino acid sequence included a 33-residue leader peptide moiety and a 394-amino acid subunit of the mature enzyme (41,385 mol wt). The T2 gene expression in fibroblasts from four patients with 3-ketothiolase deficiency was analyzed by Northern blotting. The T2 mRNA in all four cell lines had the same 1.7 kb as that of the control. However, the amounts of T2 mRNA differed: the content was reduced in two cell lines (cases 1 and 3), whereas it was within a normal range in others (cases 2 and 4). Pulse labeling followed by subcellular fractionation revealed that the T2 proteins in the fibroblasts from these patients are present in the mitochondria. These results suggest that different mechanisms are involved in the enzyme defects in the four patients.  相似文献   
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