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A pathological feature in atherosclerosis is the dysfunction and death of vascular endothelial cells (EC). Oxidized low‐density lipoprotein (LDL), known to accumulate in the atherosclerotic arterial walls, impairs endothelium‐dependent relaxation and causes EC apoptosis. A major bioactive ingredient of the oxidized LDL is lysophosphatidylcholine (LPC), which at higher concentrations causes apoptosis and necrosis in various EC. There is hitherto no report on LPC‐induced cytotoxicity in brain EC. In this work, we found that LPC caused cytosolic Ca2+ overload, mitochondrial membrane potential decrease, p38 activation, caspase 3 activation and eventually apoptotic death in mouse cerebral bEND.3 EC. In contrast to reported reactive oxygen species (ROS) generation by LPC in other EC, LPC did not trigger ROS formation in bEND.3 cells. Pharmacological inhibition of p38 alleviated LPC‐inflicted cell death. We examined whether heparin could be cytoprotective: although it could not suppress LPC‐triggered Ca2+ signal, p38 activation and mitochondrial membrane potential drop, it did suppress LPC‐induced caspase 3 activation and alleviate LPC‐inflicted cytotoxicity. Our data suggest LPC apoptotic death mechanisms in bEND.3 might involve mitochondrial membrane potential decrease and p38 activation. Heparin is protective against LPC cytotoxicity and might intervene steps between mitochondrial membrane potential drop/p38 activation and caspase 3 activation.  相似文献   
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Die Gynäkologie - Frauen im Erwachsenenalter mit einem angeborenen Herzfehler (EMAH) werden in Zukunft aufgrund des medizinischen Fortschritts eine immer größere Patientinnengruppe...  相似文献   
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In our work we investigated factors which can influence the alloimmunization and especially the ranges of cytotoxic antibodies that develop in patients on dialysis awaiting their first graft. Up to 15 liters of administered blood the proportion of immunized patients is rather stabile, not exceeding 50%. After further transfusions the percentage of immunized patients is growing rapidly reaching about 85%. Hyperimmunization, marked by cytotoxic antibodies with more than 80% panel reactivity is significantly more frequent in patients who obtained 15 and more liters of blood. In females the hyperimmunization is about 4 times more frequent than in males.  相似文献   
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We report on results of lysostrip experiments designated to analyse the molecular relations between DQ and DR antigens. The purpose of lysostrip application was to determine whether these antigens can independently be redistributed on B-cell surface by incubation with a specific antibody followed by incubation with F(ab')2 fragments of rabbit antihuman Ig. The obtained results have clearly shown that DQ antigens, and supertypic and narrow DR antigens, move independently, indicating that they are located on separate molecules, supporting the concept of different DQ and DR loci.  相似文献   
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Three patients who presented with scrotal swelling within a few days of inguinal herniorrhaphy are reported. Ultrasonography scans performed in these patients all demonstrated features suspicious of recurrence of hernia. One patient underwent surgical exploration, which revealed only a scrotal haematoma without evidence of recurrent hernia. The other two patients were managed conservatively because clinically the swellings were regarded to be more compatible with haematoma. Both patients had subsequent resolution of the scrotal swelling with no clinical evidence of recurrence of hernia on follow‐up. It is concluded that sonographic diagnosis of recurrence of hernia shortly after inguinal herniorrhaphy can occasionally be misleading.  相似文献   
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Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients.  相似文献   
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