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71.
CA19-9 widely used as a tumor marker of the pancreas and a bile duct. There are a number of reports which describes the measured value discrepancies between RIA and non-RIA kits. RIA results also have shown lack of the linearity over 70 U/ml when the samples are diluted. The pH condition at assay reaction for RIA had been suggested as the major reason, it has been denied by the results from the same pH condition at assay reaction used by COBAS CORE CA19-9 EIA II. On the other hand, the lack of RIA antibody titer is indicated for the discordant results by changing the sample volume to reagent volume ratio in the reaction. Our further investigation also indicates that the specific Lewis blood type, i.e. Le (a-b+), shows the linearity issues by RIA. The discrepancies are not caused by the reaction pH, but the amount of the antibody used in the RIA kit is closely associated. Considering the CA19-9 antibody nature used in RIA kit, which covers broad molecular range, users need to pay more attention to setting up each laboratory's measuring range.  相似文献   
72.
Out of the 365 young laboratory beagle dogs which were used in 17 toxicity bioassays, 15 cases (4.1%) were diagnosed as having congenital heterotopic gastric mucosa of the small intestine. Its incidence in the male dogs (12 cases out of 187) was higher than in the female dogs (3 cases out of 178). Grossly, the lesions were seen as an ulcerous focus of the small intestine, 25 cm to 88 cm proximal to the ileocecal valve. All of the lesions were quite similar histologically and electron microscopically to the normal gastric mucosa, which are composed of the surface mucous cells, chief cells, parietal cells, mucous neck cells and basal granulated cells of the stomach. And consequently, they were considered to be that of a congenital heterotopic tissue in the small intestine. The only morphological characteristic of these lesions different from the regular gastric mucosa was an association with the tubular structure seen in the basal region of these mucosal layers. These cells were considered to be of mucous-secreting cell origin because of secreting type III mucous evident from paradoxical concanavalin A or periodic acid Schiff stains. They seemed to be protecting the surrounding intestinal mucosa from gastric acid.  相似文献   
73.
74.
Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was  相似文献   
75.
We investigated the increase of platelet-associated IgG and complement component 3 (C3) caused by the in vitro action of anti-platelet MoAbs, and the effect of mouse and human IgG on these events. Anti-glycoprotein IIb/IIIa and anti-glycoprotein Ib MoAbs caused a slight increase of C3, but not of platelet-associated IgG. In contrast, anti-CD9 and anti-Fcγ II receptor MoAbs caused an increase of both platelet-associated C3 and IgG. In particular, three MoAbs which activated the complement system caused a marked increase of C3. When platelet-rich plasma was treated with aspirin and prostaglandin E1 before incubation with antibodies, the increase of platelet-associated IgG was inhibited in all cases. In contrast, the increase of platelet-associated C3 was scarcely influenced. These results suggest that the binding to platelets of platelet-activating antibodies caused the increase expression of IgG molecules on the platelet surface and a possible increase of platelet-associated IgG. However, the increase of platelet-associated C3 appeared to depend on specific characteristics of the antibodies tested, such as a complement-activating effect. In addition, intact mouse or human IgG inhibited the increase of platelet-associated C3 caused by complement-activating antibodies, while F(ab')2 mouse or human IgG had no such effect. This suggested that the Fc portion of IgG may block the increase of C3 mediated by anti-platelet antibodies.  相似文献   
76.
A convenient serum-free fibrin clot culture system for murine megakaryocyte progenitor cells was developed. The culture and counting of colonies is much easier in this system, when compared with previously reported serum-free culture methods. Recombinant murine interleukin-3 (rmIL-3) stimulated megakaryocyte colony formation in a dose-dependent manner in this system. While recombinant human granulocyte colony-stimulating factor (rhG-CSF) had no effect on megakaryocytopoiesis, recombinant human erythropoietin (rhEpo) and recombinant human interleukin-6 (rhIL-6) augmented megakaryocyte colony formation stimulated by rmIL-3. The depletion of adherent cells and T cells from the cultured bone marrow did not eliminate the synergistic effect of rhEpo and rhIL-6.  相似文献   
77.
78.
To clarify the essential role of NKT cells in allergy, we investigated the contribution of NKT cells to the pathogenesis of eosinophilic airway inflammation using alpha-galactosylceramide (alpha-GalCer), a selective ligand for NKT cells. Although continuous administration of alpha-GalCer during ovalbumin (OVA) sensitization increased OVA-specific IgE levels and worsened eosinophil inflammation, a single administration of alpha-GalCer at the time of OVA challenge completely prevented eosinophilic infiltration in wild-type mice. This inhibitory effect of alpha-GalCer was associated with a decrease in airway hyperresponsiveness, an increase in IFN-gamma, and decreases in IL-4, IL-5 and IL-13 levels in the bronchoalveolar lavage fluids. Analysis of lung lymphocytes revealed that production of IFN-gamma increased in NK cells, but not in T or NKT cells, following alpha-GalCer administration. Induction of vascular cell adhesion molecule-1 in the lungs of wild-type mice was also significantly attenuated by treatment with alpha-GalCer. These effects of alpha-GalCer were abrogated in J alpha281-/- mice, which lack NKT cells, and in wild-type mice treated with anti-IFN-gamma Ab. Hence, our data indicate that alpha-GalCer suppresses allergen-induced eosinophilic airway inflammation, possibly by inducing a Th1 bias that results in inhibition of eosinophil adhesion to the lung vessels.  相似文献   
79.
Lectin binding was cytofluorometrically measured on fractionated keratinocytes of guinea pig. Free keratinocytes were obtained by treatment of EDTA and trypsin. After the treatment, they were separated into 3 fractions by centrifugation on a continuous colloidal silica (Percoll) density gradient. Cells in each fraction were stained by biotinyl lectins and avidin-FITC, and fluorescence intensity was measured by cytofluorometry. Results obtained indicate that little cell surface glycoconjugate is lost during the preparation of free keratinocytes.  相似文献   
80.
A multicenter prospective study on the treatment of chronic idiopathic thrombocytopenic purpura (ITP), conducted by the Idiopathic Disorders of Hematopoietic Organ Research Committee, the Ministry of Health and Welfare of Japan, is currently in progress. In this study we analyzed the clinical records of 256 patients with chronic ITP in order to define the prognostic factors. As of November, 1988 after a median observation period of 34 months, 174 of the 256 patients (68%) were alive, 11 (4%) dead and 71 (28%) lost to follow-up. Bleeding was a direct cause of death in only one patient. Assessment of the status of patients based on platelet count at the final observation revealed that 48% of patients were in remission, 21% showed improvement, and 31% remained unchanged or worsened. Univariate analyses identified 4 parameters associated with favorable prognosis: presenting platelet count less than 2 x 10(4)/microliters, platelet count greater than 10 X 10(4)/microliters after one-year follow-up, maximal platelet count greater than 10 X 10(4)/microliters during administration of the initial dose of corticosteroids and splenectomy.  相似文献   
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