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21.
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography. 相似文献
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Blood group A immunodeterminants on human red cells differ in biologic activity and sensitivity to alpha-N-acetylgalactosaminidase 总被引:1,自引:0,他引:1
BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates. 相似文献
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WH Belloso LC Orellana B Grinsztejn JS Madero A La Rosa VG Veloso J Sanchez R Ismerio Moreira B Crabtree‐Ramirez O Garcia Messina MB Lasala J Peinado MH Losso 《HIV medicine》2010,11(9):554-564
Objective
Acquired immune deficiency appears to be associated with serious non‐AIDS (SNA)‐defining conditions such as cardiovascular disease, liver and renal insufficiency and non‐AIDS‐related malignancies. We analysed the incidence of, and factors associated with, several SNA events in the LATINA retrospective cohort.Materials and methods
Cases of SNA events were recorded among cohort patients. Three controls were selected for each case from cohort members at risk. Conditional logistic models were fitted to estimate the effect of traditional risk factors as well as HIV‐associated factors on non‐AIDS‐defining conditions.Results
Among 6007 patients in follow‐up, 130 had an SNA event (0.86 events/100 person‐years of follow‐up) and were defined as cases (40 with cardiovascular events, 54 with serious liver failure, 35 with non‐AIDS‐defining malignancies and two with renal insufficiency). Risk factors such as diabetes, hepatitis B and C virus coinfections and alcohol abuse showed an association with events, as expected. The last recorded CD4 T‐cell count prior to index date (P=0.0056, with an average difference of more than 100 cells/μL) and area under the CD4 cell curve in the year previous to index date (P=0.0081) were significantly lower in cases than in controls. CD4 cell count at index date was significantly associated with the outcome after adjusting for risk factors.Conclusions
The incidence and type of SNA events found in this Latin American cohort are similar to those reported in other regions. We found a significant association between immune deficiency and the risk of SNA events, even in patients under antiretroviral treatment. 相似文献25.
目的:为获得组织工程化自体血管,观察体外静态培养条件下犬内皮细胞与平滑肌细胞联合培养组织学及形态学的特征。方法:实验于2004-07/2005-06在首都医科大学宣武医院外科院级实验室完成。①实验材料:雄性杂种犬,3个月龄,体质量8~12kg。②实验方法:贴块法及酶解法对犬内皮细胞及平滑肌细胞进行原代分离培养及扩增,将第Ⅱ代平滑肌细胞以1×109L-1的密度种植于胶原膜上培养13d,再将第Ⅱ代内皮细胞接种于生长平滑肌细胞的胶原膜上2d。③实验评估:行苏木精-伊红染色同时扫描电镜和透射电镜观察平滑肌细胞和内皮细胞在胶原载体上联合培养后的形态。结果:苏木精-伊红染色见平滑肌细胞较均匀的分布于支架材料表面及内部;扫描电镜下,平滑肌细胞可以在胶原载体材料上生长,增殖明显并在短期内形成多层细胞。内皮细胞与平滑肌细胞联合培养2d就可在平滑肌细胞层表面获得连续的单层内皮细胞层。结论:在短期静态培养条件下犬的血管平滑肌细胞和内皮细胞可以在胶原载体材料上形成具有两层细胞结构的组织工程化动脉血管组织片。 相似文献
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自体骨髓干细胞移植治疗失代偿期肝硬化 总被引:12,自引:2,他引:12
选择36例失代偿期肝硬化患者,年龄37~59岁,患者在无菌条件下,从髂后上棘抽取骨髓100~200mL,在体外分离纯化骨髓干细胞后,局部麻醉下经股动脉插管经肝动脉将分离的骨髓干细胞移植于肝脏。自移植后12周,25例(69.4%)患者谷丙转氨酶逐渐降低,由平均(2788.56±357.90)nkat/L降至(1077.05±440.25)nkat/L;22例(61.1%)患者总胆红素逐渐下降,由平均(151.47±25.77)μmol/L降至(69.93±18.86)μmol/L;27例(75%)患者白蛋白逐渐升高,由平均(25.17±11.79)g/L升至(30.87±12.17)g/L。在干细胞移植后凝血酶原活动度逐渐上升,由术前平均(25.89±12.67)%上升至术后12周的(50.39±19.38)%,患者凝血机制明显改善。移植后大多数患者身体状况有明显的改善;移植后12周腹水减轻的19例(52.7%),食欲改善的28例(77.7%),体力好转20例(58.3%),腹胀减轻17例(47.2%),36例干细胞移植患者未出现严重并发症。 相似文献
27.
A humanised tissue‐engineered bone model allows species‐specific breast cancer‐related bone metastasis in vivo 下载免费PDF全文
VMC Quent AV Taubenberger JC Reichert LC Martine JA Clements DW Hutmacher D Loessner 《Journal of tissue engineering and regenerative medicine》2018,12(2):494-504
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients. 相似文献
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Growth factors and stromal support generate very efficient retroviral transduction of peripheral blood CD34+ cells from Gaucher patients 总被引:2,自引:1,他引:2
We have achieved high-efficiency gene transfer into nonmobilized peripheral blood (PB) CD34+ cells from patients with Gaucher's disease using a clinically acceptable retroviral supernatant transduction protocol. In our studies, bone marrow (BM) and PB CD34+ cells were transduced using a high titer (10(8) particles/mL) retroviral supernatant once a day for 4 consecutive days in the presence of interleukin-3 (IL-3), IL-6, and stem cell factor (SCF), with or without an irradiated allogeneic BM stromal layer. The growth factors alone resulted in 29% +/- 10% gene transfer of PB CD34+ clonogenic cells in contrast with 71% +/- 17% gene transfer efficiency using stroma with the growth factors; a 2.5-fold increase. The increase in gene transfer efficiency was less prominent when BM CD34+ cells were used (40% +/- 16% without and 57% +/- 8% with stroma, a 1.5-fold increase). The overall transduction efficiency of both PB and BM CD34+ cells was lower when the cells were transduced over a stromal cell layer without added growth factors. The combination of IL-3, IL-6, and SCF with stroma transduced 75% of primitive long-term culture initiating cells (PB LTC- ICs) in comparison with 34% of LTC-ICs when IL-3, IL-6, and SCF were used without stromal support. Using this clinically acceptable supernatant/cytokines/stroma transduction protocol, correction of the glucocerebrosidase (GC) deficiency in the progeny cells of PBLTC-ICs from Gaucher's-disease patients has been accomplished. Efficient transduction of the PB CD34+ cells using this transduction protocol may allow repeated delivery of "GC-corrected" hematopoietic stem and progenitor cells to Gaucher's-disease patients. 相似文献