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41.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml-1诱导HL-60细胞发生凋亡,而阻断HR20细胞于G1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml-1处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关。 相似文献
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Mediastinal tumors: biopsy under US guidance 总被引:8,自引:0,他引:8
Percutaneous biopsies of mediastinal tumors were successfully performed under sonographic guidance in 14 of 21 patients. In 10 of 11 malignant lesions, malignancy was determined by means of cytologic and histologic examination of the specimens obtained. A histologic diagnosis was reached in seven patients with malignant mediastinal tumors, including all four cases of Hodgkin lymphoma. Mediastinal biopsy under sonographic guidance is a technically simple, rapid, and accurate procedure, but its application is limited to tumors of the anterior mediastinum. 相似文献
46.
Occult cerebral vascular malformations: high-field MR imaging 总被引:4,自引:0,他引:4
Gomori JM; Grossman RI; Goldberg HI; Hackney DB; Zimmerman RA; Bilaniuk LT 《Radiology》1986,158(3):707-713
Occult cerebral vascular malformations (OCVMs) have characteristic appearances on high-field magnetic resonance (MR) images. These consist of circumscribed regions of low intensity, most prominent on T2-weighted images and representing hemosiderin deposits. Interspersed within most of these lesions are multiple areas of various signal intensity patterns, which correspond to hematomas in different stages of evolution and to fibrous regions containing calcium as well as hemosiderin. Forty-six lesions were found in 19 patients (34 supratentorial and 12 infratentorial). The supratentorial lesions tended to be subcortical or periventricular. Computed tomography depicted 24 of the 46 lesions demonstrated by high-field MR. Comparison of images obtained with both low-field MR (0.12 T and 0.35 T) and high-field MR (1.5 T) revealed that high-field MR imaging was superior in depicting OCVMs. High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions. 相似文献
47.
ZALIN AM; JONES S; FITCH NJS; RAMSDEN DB 《QJM : monthly journal of the Association of Physicians》1991,81(2):945-956
Classification of familial amyloidosis by the chemical natureof the fibrillar protein has become possible. Most such amyloidogenicproteins so far recognized are variant transthyretins, but twokindreds with the same apolipoprotein AI modification have beenreported. We describe the clinical features of another suchfamily in whom petechial skin rash appeared to be a marker forthe disease, which was non-neuropathic and of the Ostertag-type.Immunohistochemistry showed the protein to be apolipoproteinAI, but allele-specific DNA amplification indicated that itwas not the Arg26 variant previously identified. 相似文献
48.
RI Shopnick ; M Kazemi ; DB Brettler ; C Buckwalter ; L Yang ; G Bray ; ED Gomperts 《Transfusion》1996,36(4):358-361
BACKGROUND: Treatment of hemophilia patients with recombinant factor VIII concentrates has not previously been associated with anaphylaxis. STUDY DESIGN AND METHODS: A 5-week-old boy with severe hemophilia A developed dyspnea, cyanosis, hypotension, and a diffuse urticarial rash following treatment with a recombinant factor VIII (Recombinate). To identify the cause of anaphylaxis in this patient, the vial lot was examined for the presence of endotoxin, and a checkerboard immunoblotting technique was used to test serum and/or plasma samples from the patient and mother for the presence of antibodies (IgA, IgG, IgE, and IgM) to Recombinate-related antigens (recombinant factor VIII, von Willebrand factor, human serum albumin, Chinese hamster ovary proteins, bovine serum albumin, mouse monoclonal anti-human factor VIII, polyethylene glycol 3350), and to ethylene oxide, the agent used to sterilize the infusion equipment. RESULTS: No immune response directed against the Recombinate-related antigens or ethylene oxide that could be associated with the anaphylactic reaction was identified. Endotoxin was not present upon rabbit pyrogen testing of the therapeutic product. CONCLUSION: These studies failed to show any association between Recombinate and the onset of the allergic reaction. This seems to be the first reported case of anaphylaxis following the infusion of a recombinant form of factor VIII concentrate. 相似文献
49.
Discrepancies in reverse ABO typing due to prozone 总被引:5,自引:0,他引:5
Three group O sera manifesting prozone in reverse ABO tests are reported. All were implicated in erroneous blood typing results. One sample failed to react with A1 red cells (RBCs) in immediate-spin (IS) tests, had anti-A and -B titers of 8192 and 2048, respectively, by indirect antiglobulin technique (IAT), and was from a diabetic patient; the parenteral administration of A substance present in porcine insulin is a possible cause of hyperimmunity in this case. The second sample was from the recipient of a single unit of group B fresh-frozen plasma; the serum anti-A and -B titers were 10,240 by IAT, but only weak reactions with A1 and B RBCs were noted in routine IS reverse typing tests; the hyperimmunity in the patient concerned was likely due to crossreacting anti-A, B stimulated by B-active glycoproteins and/or glycolipids in the transfused plasma. The third serum also had anti-A and anti-B IAT titers of 10,240 but did not react with A1 and B RBCs by IS; the hyperimmunity in this case may be related to sepsis from intestinal flora carrying A- and/or B-like antigens. These antibodies lysed A1 and/or B RBCs in tests incubated at room temperature (RT) and strongly agglutinated those RBCs by IS when diluted 10-fold with saline. The absence of the prozone phenomenon in tests with RBCs suspended in diluents containing EDTA is consistent with the previously published mechanism for anti-A prozone: namely, the steric hindrance of agglutination by the C1 component of human complement.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
50.
Ifat Gamliel Nurit Yirmiya Dena H. Jaffe Orly Manor Marian Sigman 《Journal of autism and developmental disorders》2009,39(8):1131-1144
We compared the cognitive and language development at 4, 14, 24, 36, 54 months, and 7 years of siblings of children with autism
(SIBS-A) to that of siblings of children with typical development (SIBS-TD) using growth curve analyses. At 7 years, 40% of
the SIBS-A, compared to 16% of SIBS-TD, were identified with cognitive, language and/or academic difficulties, identified
using direct tests and/or parental reports. This sub-group was identified as SIBS-A-broad phenotype (BP). Results indicated
that early language scores (14–54 months), but not cognitive scores of SIBS-A-BP and SIBS-A-nonBP were significantly lower
compared to the language scores of SIBS-TD, and that the rate of development was also significantly different, thus pinpointing
language as a major area of difficulty for SIBS-A during the preschool years. 相似文献