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1.
Calcium carbonate was deposited by electrochemical reduction of oxygen to hydroxyl ions at various carbon-based electrodes. Although some vaterite was observed during earlier stages of the electrodeposition, the predominant polymorph during later stages was calcite. The average crystal size reached a value of 15 μm after 10 h at a glassy carbon electrode but the crystal growth rate was substantially accelerated when oxygen was catalytically reduced. The same average size of the calcite crystals in this case (Pt/C electrode) was reached within a period of 1.5 h. Efficient removal of CaCO3 from water was demonstrated when using a porous aerogel carbon electrode and a potential sufficiently negative to promote reduction of water molecules within the pores.  相似文献   
2.
The course of leukemic disease in a male adolescent with meningeal leukemia is described. The bone marrow aspirates showed a conversion from an acute lymphatic leukemia to an eosinophilic leukemia. Four weeks after the peripheral shift of phenotype two different cell clones were detected in one CSF smear. While under ultrahigh dose araC therapy the patient died 3 months after conversion. Possible explanation for the shift of phenotype and the peculiar leptomeningeal infiltration are discussed.  相似文献   
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4.
Traditional enteropathogenic Escherichia coli serotypes demonstrate a plasmid-mediated localized adherence in cultured HeLa or HEp-2 cells and induce an attaching-effacing intestinal lesion, both of which are considered pathognomonic and causes of diarrhea. This study describes three E. coli strains from infantile diarrhea which share these properties but belong to serotypes (O2:H2, O2:H25 and O15:H2) not considered enteropathogenic.  相似文献   
5.
A patient with acute monoblastic leukemia with erythrophagocytosis and a t(16;21) (p11;q22), poor response to chemotherapy, early relapse, and a short survival of ten months is presented. Hematologically, this patient could be considered as a case of FAB M5b/t(8;16) but without the characteristic chromosomal translocation, i.e., there is no visible alteration on chromosome 8 and the breakpoint on chromosome 16 appears to be very proximal. These findings are briefly discussed in the light of other variants.  相似文献   
6.
Escherichia coli strains isolated from adults with diarrhea in Bangkok, Thailand, were examined for hybridization with DNA probes for genes that code for Shiga-like toxin (SLT)-I, SLT-II, and serogroup O157 enterhemorrhagic E. coli (EHEC) fimbriae. Seven isolates that hybridized with the SLT-I, SLT-II, and O157 EHEC fimbria probes and produced verocytotoxin (VT; group A) were isolated from two patients with diarrhea. Two strains that hybridized with only the SLT-II probe and the O157 EHEC fimbria probe and were VT+ (group B) were isolated from two patients with diarrhea, 7 strains that hybridized with only the SLT-II probe and were VT+ (group C) were isolated from two patients with diarrhea, and 26 strains that hybridized with only the O157 EHEC fimbria probe and were VT- (group D) were isolated from four patients with diarrhea. Seven strains in group A had serotypes O2:H1 (n = 1), O110:H19 (n = 1), and Ont:H8 (n = 5); 2 strains in group B were O112ab:H21 (n = 1) and O113:H21 (n = 1); 7 strains in group C were O6:H28 (n = 1), O22:H16 (n = 1), O52:H25 (n = 1), O112ab:H21 (n = 1), OR:H45 (n = 2), and OR:H11 (n = 1); and 26 strains in group D were O76:H7 (n = 18), O146:H3 (n = 2), O146:H10 (n = 1), O146:Hnt (n = 1), OR:H16 (n = 1), Ont:H2 (n = 1), Ont:H8 (n = 1) and Ont:H16 (n = 1). In Thailand, E. coli strains that hybridized with SLT-I, SLT-II, and O157 EHEC fimbria probes were of a variety of serotypes, none of which were O157:H7.  相似文献   
7.
Congenital upper limb differences are frequently associated with complex syndromes. Ultrasonography is considered as the first-line diagnostic modality, and fetal MRI can be useful to further evaluate ill-defined areas. Genetic and non-invasive prenatal testing help to identify the underlying genetic disorder. The diagnostic assessment is a multidisciplinary task that should involve early prenatal consultations with specialists involved in case management and treatment planning. Obstetricians, geneticists, radiologists, psychologists and dedicated surgeons are needed to provide good parental education, prenatal and postnatal care, and successful outcomes. The purpose of this review is to provide an overview of the clinicopathologic background, current diagnostic and imaging procedures in affected fetuses.  相似文献   
8.
Summary Specimens from 490 patients with suspected legionellosis from many parts of New Zealand were studied. Most of these were sera, but 36 specimens including material from lungs, pleural fluid and sputa were also examined. The sera were tested for the presence of antibodies toLegionella pneumophila serogroups 1 to 6 andLegionella micdadei. Serological evidence of legionellosis was found in 49 patients. Antibodies toL. pneumophila serogroup 6 predominated, while those toL. micdadei andL. pneumophila serogroup 1 were noted in smaller numbers. Antibodies to serogroups 2, 3, 4 and 5 ofL. pneumophila were not often encountered.
Serologische Studien bei Patienten mit Verdacht auf Legionellose in Neuseeland
Zusammenfassung Proben von 490 Patienten mit Verdacht auf Legionellose aus zahlreichen Gegenden von Neuseeland wurden untersucht. Es handelte sich vorwiegend um Seren, in 36 Fällen konnten auch Proben von Lunge, Pleuraflüssigkeit und Sputum untersucht werden. Die Seren wurden auf Antikörper gegen die Serogruppen 1–6 vonLegionella pneumophila und vonLegionella micdadei geprüft. Bei 49 Patienten lag der serologische Beweis für eine Legionellose vor. Vorwiegend fanden sich Antikörper gegen die Serogruppe 6 vonL. pneumophila, seltener wurden Antikörper gegenL. micdadei und die Serogruppe 1 vonL. pneumophila nachgewiesen. Antikörper gegen die Serogruppen 2, 3, 4 und 5 vonL. pneumophila wurden nicht oft gefunden.
  相似文献   
9.
H Stockinger  P Valent  O Majdic  P Bettelheim  W Knapp 《Blood》1990,75(9):1820-1826
Recent data suggest that basophils express receptors for a variety of lymphokines. In this study we present the biochemical characterization of the interleukin-2 (IL-2) receptor on the basophil surface membrane. Highly enriched populations (purity: 92% to 99%) of blood basophils were obtained from chronic granulocytic leukemia (CGL) patients (n = 3) by negative selection using monoclonal antibodies (MoAbs) and complement. CGL basophils were found to bind CD25 MoAbs (n = 4) directed against different epitopes of the 55- to 60-Kd subunit of the IL-2 receptor (= Tac peptide). Immunoprecipitation experiments with lysates of purified CGL basophils and CD25 MoAbs showed a protein with a molecular weight of 60 Kd, equivalent to the Tac peptide on human T blasts. Quantitative binding studies and Scatchard plot analysis using radiolabeled recombinant human (rh) IL-2 indicated the presence of 12,000 +/- 4,700 low affinity IL-2 binding sites (kd = 66 nmol/L) per purified CGL basophil. Northern blot analysis with enriched CGL basophils showed two messenger RNA bands of 3.5 and 1.5 kilobases hybridizing to radiolabeled Tac cDNA. Immunoprecipitation of the Tac peptide from enriched basophils metabolically labeled with 35S-methionine showed active synthesis of the IL-2 receptor. Our results show that human blood basophils synthesize and express receptors for IL-2.  相似文献   
10.
Cell recognition molecules play a crucial role in the regulation of immune cells. We recently found that mast cells (MCs) express leukocyte recognition molecules, including ICAM-1 antigen, a natural ligand of LFA-1. We here report that interleukin 4 (IL-4), a pleiotropic cytokine and mast cell differentiation factor, selectively promotes expression of surface ICAM-1 antigen and ICAM-1 mRNA in human MCs. IL-4 also up-regulates ICAM-1 antigen in cells of monocyte/macrophage lineage but has no effect on ICAM-1 antigen expressed on basophils, fibroblasts, or lymphocytes. The increase in expression of mast cell/macrophage ICAM-1 antigen induced by IL-4 may contribute to the accumulation of leukocytes and facilitate cell-contact-dependent regulation of immune cells in inflamed tissues.  相似文献   
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