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931.
目的探讨黏液性肾上腺皮质腺瘤的临床病理特征。方法对1例黏液性肾上腺皮质腺瘤进行临床病理学及免疫组化分析,并进行文献复习。结果患者女,年龄40岁,上腹部、右腰部疼痛不适,增强CT示右侧肾上腺区软组织肿块。肿瘤有一层薄的纤维性包膜,突出的特征为间质内见较多的黏液,黏液内漂浮增生的多边形细胞呈条索状、假腺样、小巢样排列,多边形瘤细胞胞浆中等量,嗜酸性或嗜双色性,核圆,偶见小核仁,间质内纤维增生分隔瘤组织呈小结节状;其间夹杂有经典的肾上腺皮质腺瘤。免疫组化显示:黏液区内瘤细胞及经典的肾上腺皮质腺瘤瘤细胞阳性表达Ckpan、Syn、Inhibin-α、MelanA,不表达CK7、CK20、Villin、SMA、P63、Calponin、S100、CgA。结论黏液性肾上腺皮质腺瘤是一种少见的肿瘤,有独特的形态学表现,间质内黏液及黏液区内瘤细胞的特殊形态学表现,以及免疫组化是正确诊断和鉴别诊断的关键。 相似文献
932.
Peter Mushnikov Olga Tkacheva Vladimir Voronin Vladimir Shishkin Yuriy Zaikov 《Materials》2021,14(21)
The NdF3 solubility in molten eutectic FLiNaK, which is a conceivable medium for a molten salt reactor (MSR), was determined by the quasi-binary phase diagram FLiNaK-NdF3. The eutectic mixture FLiNaK was prepared by direct melting of components LiF, NaF and KF·HF. The acidic anhydrous salt (KF·HF) was used instead of the hygroscopic KF. The NdF3 was sintered by hydrofluorination of Nd2O3. The oxygen impurity in the prepared eutectic FLiNaK, determined by an oxygen analyzer LECO OH836, was 0.036 wt.%, whereas the NdF3 contained 0.04 wt.% of oxygen. A part of the FLiNaK-NdF3 quasi-binary phase diagram was obtained using two thermal analysis techniques: differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The FLiNaK-NdF3 phase diagram in the region of 0–30 mol.% NdF3 contains one eutectic at 2 mol.% NdF3 and 450 °C and two peritectic points: 8 mol.% NdF3 at 500 °C and 22 mol.% NdF3 at 575 °C. The region of the FLiNaK-NdF3 phase diagram below the liquidus line is rather complicated due to the complex structure of the multicomponent system in its molten state, as in its solid state. The NdF3 solubility in FLiNaK is about 5 mol.% at 490 °C and 29 mol.% at 700 °C; this means that the process of the MA transmutation in the MSR can be carried out in molten FLiNaK with a content of actinides as high as 15–20 mol.% in the temperature range of 550–650 °C. 相似文献
933.
Sieber F; Krueger GJ; O'Brien JM; Schober SL; Sensenbrenner LL; Sharkis SJ 《Blood》1989,73(1):345-350
The Friend virus complex was used as a model to study the effects of merocyanine 540 (MC 540)-mediated photosensitization on enveloped viruses. Simultaneous exposure to the lipophilic dye MC 540 and white light inactivated cell-free virus, cell-associated virus, and virus- transformed cells. When used under experimental conditions that are known to preserve most mature blood cells, at least some coagulation factors, and a significant portion of the pluripotent hematopoietic stem cell compartment, MC 540-mediated photosensitization reduced virus titers by greater than or equal to 4 log and the concentration of in vitro clonogenic erythroleukemia cells by greater than or equal to 5 log. Animals that received a single intravenous injection of photosensitized virus were resistant to a subsequent challenge with live virus. High sensitivity to MC 540-mediated photosensitization appears to be a property that is shared by other enveloped viruses. Thus, photosensitization mediated by MC 540 may be of benefit in the sterilization of blood products (in particular, cellular products), the production of vaccines, and selected areas of antiviral therapy. 相似文献
934.
The advantages of xenon include its good hemodynamic profile and possible cardioprotective properties. The investigation was undertaken to study central hemodynamics, lung gas exchange, and blood oxygen-transporting function in xenon anesthesia in patients operated on under extracorporeal circulation (EC). Fifteen patients aged 41-69 years operated on for coronary heart disease were examined. The severity of the patients' baseline status corresponded to NYHA functional classes I to IV. The duration of an operation was 251 +/- 10 min; that of EC was 97 +/- 5 min; aortic ligation lasted 59 +/- 3 min. After induction of anesthesia with propofol via concentration-regulated infusion (CRI) and with fentanyl, delivery of xenon was initiated at concentrations of 47 +/- 1 to 52.5 +/- 1%, which was mixed with oxygen. Propofol CRI was used during EC. After the latter, xenon was inhaled at concentrations of 47.7 +/- 1 to 53.3 +/- 1%. The mean arterial pressure (BP(mean)), heart rate (HR), and cardiac index (CI) remained unchanged during xenon anesthesia in the preperfusion period. After EC during xenon anesthesia, CI significantly rose with a moderate increase in HR without inotropic support. BP(mean) was moderately, but statistically significantly decreased. Prior to and following EC, there were no changes in the values of blood oxygen-transporting function. 相似文献
935.
自身免疫性肝炎患者自身抗体的测定及意义 总被引:2,自引:1,他引:2
目的:探讨自身抗体测定对诊断自身免疫性肝炎的临床意义.方法:采用间接免疫荧光法(IIF)检测47例自身免疫性肝炎患者、158例非自身免疫性肝炎患者及40例健康体检者体内抗核抗体(ANA)、抗平滑肌抗体(SMA)、抗中性粒细胞胞质抗体(ANCA)、抗线粒体抗体(AMA)等自身抗体,ELISA法检测抗MPO抗体,并对结果进行回顾性分析.结果:ANA、SMA及ANCA检出率的比较,结果显示AIH中阳性率最高为SMA(66.0%, 31/47),而非AIH中则为6.3%(10/158),两组差异有非常显著性意义(P<0.01).经X2检验, SMA、AMA和MPO抗体检测在AIH与PBC中,均有非常显著性意义(P<0.01).AIH各型自身抗体检测结果表明,AIH-Ⅰ与ANA、SMA和ANCA相关,AIH-Ⅱ与LKM相关,而AIH=Ⅲ与SLA和ANCA相关.结论:血清自身抗体的检测对诊断、治疗和阻止自身免疫性肝炎的发展有着十分重要作用,对提高AIH在临床上同其他肝病鉴别诊断和治疗有着非常重要的意义. 相似文献
936.
Holden JT; Geller RB; Farhi DC; Holland HK; Stempora LL; Phillips CN; Bray RA 《Blood》1995,86(1):60-65
Thy-1 (CDw90) is a phosphatidylinositol-anchored cell surface molecule which, when coexpressed with CD34 in normal human bone marrow, identifies a population of immature cells that includes putative hematopoietic stem cells. To date, the characterization of Thy-1 expression has been confined largely to normal tissues and cell lines. In this study, we evaluated the frequency and intensity of Thy-1 expression as defined by reactivity with the anti-Thy-1 antibody 5E10 in 38 cases of CD34+ acute leukemia (21 acute myelogenous leukemia [AML], 8 chronic myelogenous leukemia [CML] in blast crisis, and 9 acute lymphoblastic leukemia [ALL]). In 34 of 38 cases (89%) the CD34+ cells lacked expression of the Thy-1 antigen. High-density Thy-1 expression was found in 1 case of CML in lymphoid blast crisis, and low- density Thy-1 expression was identified on a portion of the leukemic cells in 2 cases of AML with myelodysplastic features, and 1 case of CML in myeloid blast crisis, suggesting a possible correlation between Thy-1 expression and certain instances of stem cell disorders such as CML and AML with dysplastic features. In contrast, the dissociation of Thy-1 and CD34 expression in the majority of acute leukemias studied suggests that the development of these leukemias occurs at a later stage than the hematopoietic stem cell. Characterization of Thy-1 expression in acute leukemia may eventually provide insights into the origin of the disease. In addition, separation of leukemic blasts from normal stem cells based on Thy-1 expression may prove useful in assessing residual disease, as well as in excluding leukemic blasts from stem cell preparations destined for autologous bone marrow or peripheral stem cell transplantation. 相似文献
937.
Survival or death of individual proerythroblasts results from differing erythropoietin sensitivities: a mechanism for controlled rates of erythrocyte production 总被引:10,自引:8,他引:10
Murine erythroid progenitors infected with the anemia-inducing strain of Friend virus (FVA cells) undergo apoptosis when deprived of erythropoietin (EPO). When cultured with EPO, they survive and complete terminal differentiation. Although cell volume is decreased and nuclear chromatin is condensed during both apoptosis and terminal differentiation, morphologic and biochemical distinctions between these two processes were observed. In apoptosis, homogeneous nuclear condensation with nuclear envelope loss occurred in cells that had not reached the stage of hemoglobin synthesis. In terminal erythroid differentiation, nuclear condensation with heterochromatin, euchromatin, and nuclear envelope preservation occurred simultaneously with hemoglobin synthesis. Cells with apoptotic morphology appeared asynchronously in EPO-deprived cultures, indicating that only a portion of the cells were undergoing apoptosis at any given time. The percentages of apoptotic cells and cleaved DNA increased with time in EPO-deprived cultures. Inhibition of DNA cleavage was directly proportional to EPO concentration over a wide physiologic range, demonstrating a heterogeneity in susceptibility to apoptosis based on variability in the EPO sensitivity of individual cells. A subpopulation of FVA cells with increased EPO sensitivity (decreased EPO requirement) was isolated from EPO-deprived cultures. This increased EPO sensitivity did not result from differences in EPO receptor number, affinity, or structure, suggesting that the differences are in the signal transduction pathway. These results indicate that control of red blood cell production involves both prevention of apoptosis by EPO and heterogeneity in the EPO requirement of individual progenitor cells. 相似文献