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991.
992.
The aim of this study was to quantify and characterise the CD4+ and CD8+, CD45RA+, CD45RO- T-lymphocytes that paradoxically expressed the CD29 bright+ phenotype in health and in rheumatoid arthritis. We further evaluated their clinical implications. Blood samples were obtained from 100 patients with rheumatoid arthritis and 40 age- and sex-matched controls. Cell surface antigens and interleukin-2 (IL-2) binding were detected on CD4+ and CD8+ peripheral blood T-lymphocytes (T-PBL) by three-colour flow cytometry. One-third of the patients were clinically evaluated at the time of blood sampling. In healthy donors, we found 16 ± 14% of CD29 bright+cells among CD4+, CD45RA+, RO-T-PBL. These false naive CD4+ T-PBL were Leu-8+, and a majority expressed the CD25/p55 receptor (IL-2R chain), while a minority showed the CDlla bright+, CD69+ and/or CD 122/p75+ (IL-2R chain) phenotype, and few cells were CD31 bright+ and HLA-DR+. In rheumatoid arthritis, their proportion among CD4+, CD45RA+, RO- cells increased to 25 ± 15% (P < 0.001, compared with controls). In patients, the reductions in CD31 and CD38 expression (P < 0.05 for both), as well as the enhanced CD25 expression (P < 0.001) on CD4+, CD45RA+, RO- T-PBL reflected a more differentiated phenotype. The occurrences of CD25 and CD122 were increased on false naive CD4+ T-PBL (0.01 <P<0.001); however, the binding of IL-2 remained very low (in contrast to the binding of IL-2 on CD45RO+ T-PBL). Furthermore, a major subset of CD8+, CD45RA+, RO- T-PBL (45 ± 17% in controls) expressed the CD29 bright+ phenotype. These false naive CD8+ T-PBL included a great many of CID 1lb+, CD28- cells, while a minority showed the HLA-DR+, CD69+ and/orCD122+ phenotypes. Patients with low levels of IgM rheumatoid factors (IgM-RF; but with active disease) had an elevated proportion of CD45RA+, RO-cells among the CD8+ T-PBL, in part due to an increased proportion of false naive cells (P < 0.05). In patients, the false naive CD8+ T-PBL showed down-regulated CD1lb and an increased expression of IL-2 receptor chains (CD25 and CD 122; 0.05 <P < 0.01), but without a significant increase in IL-2 binding. More CD69 on false naive CD8+ T-PBL was found in patients with high levels of IgM-RF (P < 0.005 compared to patients with low 19M-RF). Finally, both false naive CD4+ and CD8+ T-PBL correlated with the clinical process and outcome variables (0.05 <P <0.01). The levels of activated false naive CD4+ T-PBL (CD25+ and/or CD122+) or CD8+ T-PBL (CD69+ and/or CD122+) were associated with clinical parameters of disease activity (0.05 <P < 0.01). Thus, in rheumatoid arthritis, false naive T-PBL showed important qualitative differences. The levels of activated false naive T-PBL could be particularly interesting for monitoring disease evolution.  相似文献   
993.
Previous studies suggest that lung function tests using monodisperse aerosols can help to identify early stages of lung diseases. We investigated intrapulmonary particle loss and aerosol bolus dispersion-a marker of convective gas transport-in 32 women with asymptomatic nonspecific bronchial hyperresponsiveness (BHR) compared with 60 women without BHR. Deposition of inhaled particles (0.9 micrometer mass median aerodynamic diameter [MMAD]) was calculated from particle losses of inhaled aerosol boluses consisting of di-2-ethylhexyl sebacate droplets. Convective gas mixing was assessed by the aerosol bolus dispersion method. Women with BHR, nonsmokers as well as smokers, showed significantly increased deposition of aerosol particles (nonsmokers: 45.6 +/- 8.8%; smokers: 49.2 +/- 5.4%; mean +/- SD) compared with the control group of female nonsmokers without BHR (38.2 +/- 9.1%; mean +/- SD) (p < 0.01). Aerosol bolus dispersion values showed a trend for higher values in subjects with BHR (nonsmokers: 572 +/- 122 cm3; smokers: 587 +/- 85 cm3) compared with the control group (542 +/- 88 cm3) (p = 0.2). Also, the maximal expiratory flow at 25% vital capacity (MEF25) showed a trend for decreased values in nonsmokers with BHR compared with nonsmokers without BHR (64 +/- 16% of predicted versus 78 +/- 24% of predicted; p = 0.03). These results suggest that deposition of inhaled particles (0.9 micrometer MMAD) administered by the aerosol bolus technique is a sensitive index of peripheral lung injury that is usually not assessable by conventional methods.  相似文献   
994.
995.
The two dimensional echocardiographic findings of aortic root abscess have been described. The echocardiographic findings in a patient with aortic valve endocarditis complicated by abscess formation, tear in the intima of the ascending aorta, and rupture of abscess cavity into the right ventricle are reported.  相似文献   
996.
Rudolf Schindler was born in Berlin and achieved his international reputation with the textbook "Lehrbuch und Atlas der Gastroskopie", written in Munich. This was the first book containing excellent endoscopic pictures. He was the first to report on more than four hundred gastroscopies performed without complications. 1928 to 1932, he developed the first semi-flexible gastroscope together with the technical designer Georg Wolf from Berlin. This became the lasting standard for about twenty-five years. In 1934, Schindler emigrated to Chicago after being released as a Nazi prisoner. In 1937, he was awarded the gold medal for his research on gastritis by the American Medical Association. He became the leading person among American gastroscopists for many years and, in 1941, the first president of the American Gastroscopic Club. After 1943 he moved to California to work and live. He also received awards from the American Societies for Gastroscopy and Gastrointestinal Endoscopy in 1953 and 1962. He spent his last years in Munich. His honorary titles of father, architect or super salesman of gastroscopy describe the spectrum of his personality. He was an endoscopist with outstanding technical and diagnostic skills and knew particularly how to deal with patients, how to develop endoscopes as well as being a highly qualified teacher, author and scientist. He also had many hobbies, in particular playing and conducting music perfectly.  相似文献   
997.
Haploidentical hematopoietic cell transplantation (HHCT) after high dose conditioning with CD34-selected stem cells has been complicated by high regimen related toxicities, slow engraftment and delayed immune reconstitution leading to increased treatment related mortality (TRM). A new regimen using reduced intensity conditioning (RIC) and graft CD3/CD19 depletion with anti-CD3 and anti-CD19 coated microbeads on a CliniMACS device may allow HHCT with lower toxicity and faster engraftment. CD3/CD19 depleted grafts not only contain CD34+ stem cells but also CD34 negative progenitors, natural killer, graft facilitating and dendritic cells. RIC was performed with fludarabine (150-200 mg/m(2)), thiotepa (10 mg/kg), melphalan (120 mg/m(2)) and OKT-3 (5 mg/day, day -5 to +14) and no posttransplant immunosuppression. Twenty nine patients (median age=42 (range, 21-59) years) have been transplanted with this regimen. Diagnosis were AML (n=16), ALL (n=7), NHL (n=3), MM (n=2) and CML (n=1). Patients were "high risk" with refractory disease or relapse after preceding HCT. The CD3/CD19 depleted haploidentical grafts contained a median of 7.6x10(6) (range, 3.4-17x10(6)) CD34+ cells/kg, 4.4x10(4) (range, 0.006-44x10(4)) CD3+ T cells/kg and 7.2x10(7) (range, 0.02-37.3x10(7)) CD56+ cells/kg. Donor-recipient KIR-ligand-mismatch was found in 19 of 29 patients. The regimen was well tolerated with maximum acute toxicity being grade 2-3 mucositis. Because of severe neurotoxicity in 4 patients treated with 200 mg/m(2) fludarabine, the dose was reduced to 150 mg/m(2). Engraftment was rapid with a median time to >500 granulocytes/microL of 12 (range, 10-21) days, >20,000 platelets/microL of 11 (range, 7-38) days and full donor chimerism after 2-4 weeks in all patients. Incidence of grade II-IV degrees GVHD was 48% with grade II degrees =10, III degrees =2 and IV degrees =2. One patient, who received the highest T-cell dose, developed lethal grade IV GVHD. TRM in the first 100 days was 6/29 (20%) with deaths due to idiopathic pneumonia syndrome (n=1), mucormycosis (n=1), pneumonia (n=3) or GVHD (n=1). Overall survival is 9/29 patients (31%) with deaths due to infections (n=7), GVHD (n=1) and relapse (n=12) with a median follow-up of 241 days (range, 112-1271). In conclusion, this regimen is promising in high risk patients lacking a suitable donor, and a prospective phase I/II study is ongoing.  相似文献   
998.
Angiogenesis is an important component in many biological processes and also in pathologic conditions including neoplastic diseases. Vascular endothelial growth factor (VEGF) is a secreted endothelial cell-specific growth factor, which is induced by tissue hypoxia and is angiogenic in vivo. Adrenal gland is a well-vascularized organ, and the roles of VEGF in normal adrenal and in adrenal tumorigenesis is not well characterized. We therefore investigated VEGF mRNA expression in normal human adrenals and in cultured adrenocortical cells. VEGF mRNA was constantly expressed in normal adrenals as well as in cultured adrenocortical cells. The mRNA levels were increased after 24h stimulation with either ACTH or cAMP. The effect of cAMP was dose-dependent. This suggests that ACTH-induced VEGF mRNA expression is mediated via protein kinase A dependent pathway.  相似文献   
999.
Morphological findings in joint cartilage after osmic acid treatment   总被引:1,自引:0,他引:1  
Punch biopsy specimens from the cartilage of the lateral condyle of the femur in 29 patients suffering from rheumatoid arthritis were taken during surgical synovectomy of knee joints and investigated by light or electron microscopy. Eleven patients had never received osmic acid injections in this particular joint, whereas 18 had had such injections 1-24 months prior to surgery. By light microscopy only minor differences could be seen between controls and cartilage treated with osmic acid, whereas with electron microscopy, increased amounts of dark-staining cell debris were visible in samples taken after osmic acid treatment. The perilacunar matrix appeared normal. There was no irregularity of collagen fibres at the surface of the cartilage. It is concluded that osmic acid causes limited superficial damage to the cartilage. The question whether this is of any clinical consequence in the form of subsequent degenerative joint disease, must be solved by clinical follow-up studies.  相似文献   
1000.
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