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991.
Fine-needle aspiration (FNA) is a reliable, safe, and cost-effective procedure with a well-established role in the diagnosis of various solid tissue neoplasms. The role of FNA in the diagnosis of primary bone tumors, including osteosarcoma (OGS), is controversial and has yet to be established. We reviewed our experience with the use of FNA as a diagnostic technique over the past 8 yr at our institution. Diagnosis was conclusive in 26 (65%) of 40 patients, 18 of whom went to neoadjuvant therapy and/or resection based solely on the FNA interpretation of either "high grade sarcoma" or "osteosarcoma." Of the remaining 14 (25%) patients, 12 had inconclusive diagnosis and two (5%) were false-negatives. An inconclusive diagnosis was most likely to be an inadequate or paucicellular aspirate, seen in six (15%) patients. An additional six patients had variants of osteosarcoma (four chondroid, one "giant cell rich," one parosteal) that made definitive diagnosis impossible. The two that were incorrectly classified were diagnosed as fracture callus and plasmacytoma. FNA is an accurate and cost-effective tool for the initial diagnosis of primary osteosarcoma with a sensitivity of 65% and accuracy of 95%. Inconclusive diagnoses are likely to be due to insufficient sample cellularity or the presence of OGS variant. In our experience, FNA is sufficient to provide the diagnosis of OGS prior to definitive treatment when interpreted in conjunction with imaging studies and clinical findings. In those cases where FNA fails to yield a diagnostic sample, a traditional biopsy can be performed. 相似文献
992.
Voltage- and Ca(2+)-dependent K(+) channels in the membrane of both T and B lymphocytes are important for the cellular immune response. In the current issue of the European Journal of Immunology, Reich et al. demonstrate that selective blockade of the intermediate-conductance Ca(2+)-activated K(+) channel (the IK channel encoded by the KCNN4 gene) prevents cytokine production in the spinal chord and ameliorates the development of EAE caused by injection of myelin oligodendrocyte glycoprotein (MOG)(35-55) in mice. These data renew the focus on the IK channel as a potential target for the development of new immune-suppressant drugs for the treatment of autoimmune diseases. 相似文献
993.
994.
Prof. Dr. A. Helber G. Wambach W. Hummerich G. Bönner K. A. Meurer W. Kaufmann 《Journal of molecular medicine (Berlin, Germany)》1980,58(9):439-447
Summary In patients with grade I and II essential hypertension studied during sodium loading (Na+ excretion above 175 meq·d–1) we found a bimodal behaviour of aldosterone excretion and could distinguish two groups of patients: In the major part of essential hypertensives sodium loading led to a suppression of aldosterone excretion below 6 µg·d–1, which is the highest control value during sodium loading, with an average of 2.7±1.4 (SD) µg·d–1. Aldosterone excretion in a second group of patients was not suppressible below 6 µg·d–1 despite forced sodium loading; it resulted in an average value of 10.0±3.0 (SD) µg·d–1. During sodium deprivation or free sodium intake, aldosterone excretion in the first group of patients followed exactly the behaviour of normotensive controls, while in the second group of essential hypertensives the correlation of aldosterone excretion and log. Na excretion or log. Na+/K+ ratio in 24 h urine (r=–0.59) was far below the control value ofr=–0.87. Serum potassium concentration during sodium loading was significantly (p<0.001) lower (3.81±0.44 meq·l–1) in the essential hypertensives with non-suppressible aldosterone excretion compared to those with suppressible aldosterone excretion (4.26±0.37 meq·l–1). The blood pressure response to treatment with 200 mg spironolactone·d–1 was better (p<0.05) in patients with non-suppressible aldosterone excretion compared to the essential hypertensives with normal aldosterone regulation. The plasma renin activity of both groups of patients was not significantly different, however, a tendency prevailed towards lower PRA-values in the patient group with non-suppressible aldosterone excretion during sodium loading.With the technical help of Mrs. R. Schendschilorz and Mrs. G. Suckau 相似文献
995.
Antibody against fusarochromanone (TDP‐1) was obtained from rabbits after immunization with TDP‐1 conjugated to bovine serum albumin (BSA). An indirect enzyme‐linked immunosorbent assay (ELISA) using TDP‐1‐ovalbumin conjugate as the antigen coated on to the microtiter plate was used for monitoring the antibody liter. For toxin detection, a direct competitive ELISA in which TDP‐1 was conjugated to horseradish peroxidase (HRP) was used. Competitive direct ELISA revealed that the antibody had about 5.6 and 4.5 times greater binding efficiency for monoacetyl fusarochromanone (TDP‐2) and diacetylated TDP‐1 than TDP‐1. The concentration causing 50% inhibition of binding of TDP‐1‐HRP to the antibody by TDP‐1, TDP‐2 and diacetyl‐TDP‐1 were 2.8, 0.5 and 0.62 ng/ml, respectively. For the analysis of fusarochromanones in wheat and barley, the toxins were first extracted from the commodities with 100% methanol. A small aliquot of the extract was dried, acetylated, diluted in buffer and then analyzed directly by ELISA. The overall recovery for fusarochromanone in the wheat and barley samples spiked with TDP‐1 in the concentration range of 20 to 500 ppb were found to be 97% and 103.4% with cv of 15% and 11.2% for barley and wheat, respectively. 相似文献
996.
Curt A. Sandman Jack M. George J.Dennis Nolan Henk Van Riezen Abba J. Kastin 《Physiology & behavior》1975,15(4):427-431
Normal men were infused for 4 hr with ACTH/MSH 4–10 or a control solution. Behavioral testing after the infusion indicated that subjects who received ACTH/MSH 4–10 were less anxious and had better visual memory than control subjects but the predominant effect of the heptapeptide was to increase visual attention. It was specualted that ACTH/MSH 4–10 may be uniquely coded for attentional functioning. 相似文献
997.
老化态度问卷的编制及其初步试用 总被引:5,自引:0,他引:5
目的:编制老化态度问卷。方法:通过调查和参考国外量表,组成问卷。在老年人中使用后,对问卷进行各项量表属性分析。结果:根据项目分析结果。对条目筛选后的老化态度问卷,因此分析显示具有两个主成分。内部一致性信度和复测信度达到0.9以上。分半信度0.77。结论:自编老化态度问卷具有良好信度,效度。 相似文献
998.
目的 检测肺鳞状细胞癌中死亡相关蛋白激酶 (DAP K)mRNA表达及细胞凋亡 ,探讨DAP K与细胞凋亡的关系及其在肺鳞状细胞癌发生、发展中的作用。方法 用原位分子杂交法检测 6 0例肺鳞状细胞癌、9例癌旁肺组织DAP KmRNA表达 ;用原位末端标记TUNEL法检测相应组织中细胞凋亡 ,计算凋亡指数 (AI)。结果 肺鳞状细胞癌的DAP KmRNA阳性表达率为 4 6 7% ,癌旁肺组织为 6 7 7% ,其阳性率高于肿瘤组织 (P <0 0 1 )。在肺鳞状细胞癌中 ,高分化癌DAP KmRNA阳性率为 70 % ,低分化癌为 2 3 3% ,高分化癌的DAP KmRNA阳性率高于低分化癌 (P <0 0 1 )。肺鳞状细胞癌的细胞AI为(0 6 72 8± 0 4 2 6 1 ) % ,癌旁肺组织中支气管肺泡上皮细胞AI为 (1 0 2 89± 0 2 4 33) % ,癌旁肺组织的AI高于肿瘤组织 (P<0 0 1 )。在肺鳞状细胞癌中 ,高分化癌的AI为 (0 5 82 3± 0 1 92 2 ) % ,低分化癌为 (0 4 4 6 0± 0 1 92 5 ) % ,高分化癌的AI高于低分化癌 (P <0 0 1 )。DAP KmRNA呈阳性表达的肺癌 ,其AI为 (0 5 31 7± 0 2 0 97) % ;DAP KmRNA呈阴性者 ,其AI为 (0 4 872± 0 1 91 8) % ,两组间差异有显著性 (P <0 0 5 )。在连续切片上 ,DAP KmRNA阳性细胞的分布区域与凋亡阳性细胞的分布相似。DAP KmRNA呈阳性表达 相似文献
999.
Engstrand M Lidehall AK Totterman TH Herrman B Eriksson BM Korsgren O 《Clinical and experimental immunology》2003,132(1):96-104
The availability of tetrameric complexes of HLA class I molecules folded with immunodominant peptides makes it possible to utilize flow cytometry for rapid and highly specific visualization of virus specific CD8+ T cells. An alternate technique is to incubate whole blood with specific antigens and to subsequently detect and characterize responding T cells (e.g. by performing intracellular staining of interferon-gamma). By using an HLA-A2 tetramer construct folded with the same immunodominant CMV-peptide as that used for peptide pulsing, we monitored both the presence and functional capacity of CMV-specific CD8+ T cells. In addition T cell activation was assayed by determination of CD38 and CD69 expression. Twelve organ transplant patients and 31 healthy blood donors with latent CMV infection were investigated using CMV pp65 tetramer staining and intracellular staining of interferon-gamma after CMV pp65 peptide pulsing or CMV lysate pulsing. CMV-specific T cells were detected in similar absolute numbers as well as frequencies of T cells in the two groups investigated. However, the CMV-specific CD8+ T cells in immunosuppressed individuals showed a decreased functional response to the CMV-peptide, as evidenced by reduced interferon-gamma production when compared to healthy blood donors (19%; 42%, P < 0.005). In addition, CD38 expression was markedly higher in immunosuppressed patients compared to healthy blood donors (24%; 6%, P < 0.005). In a case report we demonstrate that reactivation of CMV can occur in an immunosuppressed patient with high number of CMV-specific T cells, but without functional capacity. Hence, these findings reflect impaired activation of cytotoxic T cells controlling latent CMV infection in immunosuppressed patients. 相似文献
1000.
音猬因子的功能受体斑片在培养神经干细胞中的表达 总被引:1,自引:0,他引:1
目的 观察在培养的神经干细胞内是否有发育调控分子———音猬因子 (sonichedgehog)功能受体———斑片 (patched)表达。 方法 神经干细胞克隆在体外培养传代后 ,用patched的特异性引物对培养的神经干细胞进行RT PCR分析 ,PCR产物经克隆测序后 ,用地高辛标记克隆的探针 ,对神经干细胞进行原位杂交分析。 结果 神经干细胞克隆内大量的细胞均可表达sonichedgehog的功能受体patched ,patched阳性细胞间未见明显差别 ,克隆边缘与中央的patched分布也未见明显差别。 结论 sonichedgehog信号传导路可能在神经干细胞的增殖与分化过程中起重要作用。 相似文献