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The distribution patterns of choline acetyltransferase (CAT), as a marker for cholinergic neurons, and Calbindin-D28k (CaBP) immunoreactivities in the forebrain basal ganglia of the Japanese monkeyMacaca fuscata were compared. Similar distribution patterns of CAT and CaBP immunoreactivities were found in the medial septal nucleus (MS) and the nucleus of the diagonal band of Broca (DBB). Double-labeling fluorescence immunocytochemistry revealed that most, but not all, cholinergic neurons were CaBP-immunoreactive in the MS and DBB. The results suggest that CaBP may play a role in the septohippocampal cholinergic neuron system of the monkey.  相似文献   
23.
Two flat adenomas and a flat mucosal carcinoma of the colon were reported in patients with synchronous and metachronous colonic carcinomas. These lesions were almost flat and were not detected by preoperative endoscopic examinations. Colonoscopists should be aware of the presence of flat adenomas, which can be easily missed, and recognize them as lesions that play an important role in the "adenoma-carcinoma sequence."  相似文献   
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Human parvovirus B19 (B19) infects cells of erythroid lineage. Production of neutralizing antibodies (Abs) is indispensable for recovery from B19-related disease state. In this study, we used a convenient method to measure neutralizing activities in human sera by using a real-time quantitative PCR based assay. Erythroid cell line KU812Ep6 was incubated with test sera before infection with B19 virus. The copy number of B19-DNA in cultures was decreased in the presence of the sera from patients who recovered from acute B19 infection, whereas no decrease in B19-DNA was in cultures incubated with sera from healthy volunteers who had no B19 infection. The decrease in B19-DNA copy number was calculated and the inhibition percentage was expressed as neutralizing activity to B19. A clinical study showed that the levels of neutralizing ability were high in patients who recovered soon after acute B19 infection, but were low in some patients with a prolonged clinical course for recovery from B19 infection. This method is simple and convenient compared with methods described previously, showing its usefulness to evaluate the neutralizing activity to B19.  相似文献   
26.
The formation of metastases in multiple organs and acquired multi-drug resistance (MDR) are the major obstacles for treatment of human small-cell lung cancer (SCLC). To explore the possibility of immunological overcoming of multiple-organ metastases produced by refractory SCLC, we established the MDR variant (SBC-3/DOX), expressing P-glycoprotein, of parental SBC-3 cells by culturing with gradually increasing concentration of adriamycin. Both SBC-3 and SBC-3/DOX cells expressed a high amount of ganglioside GM2, an ideal target of SCLC cells. A mouse-human chimeric anti-GM2 monoclonal antibody (KM966) induced antibody-dependent cellular cytotoxicity (ADCC) mediated by human mononuclear cells (lymphocytes and monocytes) and complement-dependent cytotoxicity (CDC) mediated by human AB serum against SBC-3/DOX cells to a similar extent compared with parental SBC-3 cells. Pretreatment of human effector cells with various cytokines induced further enhancement of the KM966-dependent ADCC against SBC-3/DOX cells. Intravenous injection of SBC-3 or SBC-3/DOX cells into natural killer (NK) cell-depleted severe combined immunodeficient (SCID) mice developed metastases in multiple organs (liver, kidneys and lymph nodes). Interestingly, SBC-3/DOX cells produced metastases more rapidly than SBC-3 cells, suggesting more aggressive phenotype of SBC-3/DOX cells than their parental cells in vivo. Systemic treatment with KM966, given on days 2 and 7, drastically inhibited the formation of multiple-organ metastases produced by both SBC-3 and SBC-3/DOX cells, indicating that KM966 can eradicate metastasis by SCLC cells irrespective of MDR phenotype. These findings suggest that the mouse-human chimeric KM966 targets the GM2 antigen, and might be useful for the immunological circumvention of multiple-organ metastases of refractory SCLC. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
27.
To clarify the correlation of genomic alterations with clinical and histological features, we performed metaphase comparative genomic hybridization analysis on 20 primary cutaneous melanomas, which were obtained by laser capture or manual microdissection, and 16 melanoma cell lines. There were no differences in the average number of aberrations between acral melanomas (AM) and non-AM, although gains of 5q and 11q13 were more frequent (P=0.05) and 10q loss was less frequent (P=0.01) in AM than in non-AM. Although tumor thickness is considered a measurable estimate of clinical expression, there were no differences in the average number of aberrations among 4 groups, classified by thickness of the tumor. While the majority of aberrations were equally distributed among the 4 groups, 6p gains were found only in the thickest tumors. Patients with 6p or 1q gains had a lower overall survival rate than those without them (P=0.0002 or P=0.013). While gains of 1q, 2q, 3p, 3q, 7q, 20p, and 20q were more frequent in the cell lines than in the primary tumors (P<0.01), losses of 6q, 9p, 10p, and 10q were equally found in both cell lines and primary tumors. The present study showed that chromosomal aberrations had already occurred in the thinner tumors, and that 6p and 1q gains may be a prognostic factor.  相似文献   
28.
To clarify the invasive process of Vibrio parahaemolyticus, an invasion assay was performed using cells expressing dominant negative small GTPases of the Rho family. This assay showed that the dominant negative host phenotype facilitates bacterial invasion, suggesting that the mechanism of V. parahaemolyticus invasion differs from that reported for other invasive bacteria.  相似文献   
29.
Ossifying fibromyxoid tumor (OFMT) of soft parts is a recently described, rare but morphologically distinctive soft tissue tumor. The histogenesis of this lesion remains uncertain, although several immunohistochemical and ultrastructural features suggest that it is an unusual neural tumor, possibly of Schwann cell origin. We report here a case of a malignant variant of OFMT that occurred in the foot of a 52-year-old man. The karyotype of a pulmonary metastasis exhibited the following complex numeric and structural aberrations:72 approximately 74,XXY,-5,+6,+del(8)(p21),del(9)(p22),+10,der(11)t(3;11)(p21;p15),del(12) (q13),der(13)t(5;13)(q13;q34),+18,+19,+20,-22 [cp10]. A kidney metastasis exhibited the following karyotypic abnormalities: 46,XY,add(3)(p11),+der(3)t(3;?;11)(3qter-->3p11::?::11q13-->11qter), -5,del(8)(p21),add(9)(q22),del(9)(p22),der(11)t(3;11)(p21;p15),del(12)(q13),+der(13)t(5;13) (q13;q34),-22. To our knowledge, this is the first reported case of OFMT in which clonal chromosomal aberrations have been shown.  相似文献   
30.
Four cases of Ischemic enterocolitis without arterio–occlusive lesion were described. Three cases were associated with sigmoid colon carcinomas. Ischemic lesions developed anal to the carcinomas in two cases, and oral to sigmoidostomy to relieve intestinal obstruction by carcinoma in one case. One other case was associated with inguinal hernia. Grossly, ischemic lesions involved relatively short intestinal segments, and the ischemic colonic lesions were not related to teniae coli. Extensive veno–occlusive lesions were discovered in a case of ischemic stricture of the ileum, which had been incarcerated in the right inguinal hernia. Reversible mechanical occlusion of the intestinal vessels caused by transient or recurrent intestinal strangulation is the most probable cause of these ischemic lesions., ACTA PATHOL. JPN. 33: 249–256, 1983.  相似文献   
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