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61.
We reported a new monoclonal antibody, designated FUB-1, reacting with normal and neoplastic large lymphoid cells. FUB-1 was produced using a Burkitt's lymphoma cell line (HBL-5) as an immunogen. Its immunoglobulin subtype was IgM. The determinant was not on the surface but in the cytoplasm. Western blotting analysis revealed that the molecular weight of the antigen was 52,000 dalton. In the normal lymphoid tissue, FUB-1 reacted with large lymphoid cells, but not with small or medium-sized lymphoid cells or plasma cells. In addition, the FUB-1 antigen was not found in resting cells in the peripheral blood (PB), but it was induced on mononuclear cells of PB by addition of PWM or PMA. In the B-cell lymphomas tested, FUB-1 reacted with small cleaved cell lymphomas (3/12), large cell lymphomas (7/10), Burkitt's lymphomas (4/4) and immunoblastic lymphomas (2/2), but not with small cell lymphomas (0/3) or intermediate lymphocytic lymphomas (0/8). These findings indicate that the FUB-1 antigen appears to be expressed on normal lymphoid cells during blastoid transformation and on neoplastic large lymphoid cells. FUB-1 also reacted with normal glandular epithelium and various adenocarcinomas. FUB-1 may be useful to investigate the mechanism of in vitro blastoid transformation or activation of lymphoid cells.  相似文献   
62.
Crystal-matrix interrelations in brushite and uric acid calculi   总被引:1,自引:0,他引:1  
Brushite and uric acid calculi were studied by means of scanning electron microscopy with the partial dissolution method and transmission electron microscopy. Brushite calculi consist of radially oriented columnar crystals which have sheet-like substructure. The organic matrix is identified chiefly at the outside of the crystals but partly included between the substructure. The concentric matrix bands are often dislocated between the neighbouring crystals. Uric acid calculi also consist of radially oriented columnar crystals, and a fine meshwork of the organic matrix is incorporated within the crystals. The concentric matrix layers of different density are angled according to the crystal lattice. These findings indicate that the organic matrix arose from a mucinous surface coat, at least in the radially striated calculi. The crystals continued to grow in this gel-state milieu, either thrusting the matrix aside or incorporating it within the crystals.  相似文献   
63.
While nonspecific airway hyperresponsiveness (AHR) is a central feature of allergic bronchial asthma, the mechanism underlying the development of AHR is not clearly understood. We have previously demonstrated in vitro hyperresponsiveness of bronchial smooth muscle to acetylcholine (ACh) in rats that were actively sensitized and repeatedly challenged with aerosolized antigen. It has also been demonstrated that the ACh-induced, RhoA-mediated Ca(2+) sensitization is markedly augmented concomitantly with an increased expression and activation of RhoA protein in the bronchial smooth muscle of the antigen-treated rats. In the present study, we have investigated whether TNF-alpha, a proinflammatory cytokine which is involved in bronchial asthma, causes upregulation of RhoA mRNA and protein in the rat bronchus. Treatment of rat bronchial smooth muscle preparations with TNF-alpha (300 ng/ml for 24 hr) significantly shifted the concentration-response curve to ACh upwards, but did not alter the response to high K(+), when compared to that of control tissues. Levels of RhoA mRNA and protein in the TNF-alpha-treated bronchus were significantly greater than those in the control group. In conclusion, it is suggested that the augmentation of the ACh-induced contractile response evoked by TNF-alpha might be mediated by an upregulation of RhoA in rat bronchial smooth muscle.  相似文献   
64.
65.
The actions and interactions of purified recombinant human (rh) interleukin 4 (IL-4) and granulocyte colony-stimulating factor (G-CSF) on the clonogenicity of human leukemic cell line U937 were studied in vitro. Parameters analyzed were the suppression of stem cell generation using sequential clonal cultures, alterations of surface antigen expression, and morphological changes. IL-4 alone (10 U/ml) and G-CSF alone (1000 U/ml) only slightly reduced colony numbers (80% +/- 7% and 87% +/- 7% of control colonies, respectively). However, IL-4 interacted synergistically with G-CSF to further reduce the colony number (46% +/- 8% of control colonies) and suppress the self-renewal ability (clonogenicity) of U937 cells. This synergistic effect was not eliminated by cultures containing neutralizing concentrations of anti-granulocyte-macrophage colony-stimulating factor (anti-GM-CSF), anti-interleukin 6 (anti-IL-6), anti-interferon-alpha (anti-IFN-alpha), anti-IFN-gamma, anti-transforming growth factor-beta (anti-TGF-beta) serum, and anti-tumor necrosis factor-alpha (anti-TNF-alpha) serum. The coexistence of IL-4 and G-CSF was required for at least 48 h to reveal the synergistic action as assessed by preincubation and delayed addition experiments. Combinations of IL-4 and G-CSF showed a significant increase in CD11b expression on U937 cells. This action was not observed with HL60, K562, ML-1, or KG-1 leukemic cell lines, and IL-4 did not show any synergistic suppression of clonogenicity of U937 leukemic cells in combination with other cytokines tested in this study. These results suggest that IL-4 in combination with G-CSF may have some capacity to synergistically suppress human leukemic cells of specific types with loss of clonogenicity.  相似文献   
66.
A 60-year-old man suffered from paraplegia after the operation for thoracic aortic aneurysm and died 10 months after the operation. Detailed examination on the distribution of spinal cord lesions and of the locations of anterior radicular arteries revealed that the spinal cord ischemia occurred at the mid-thoracic segments between T-6 and T-10; the artery of Adamkiewicz entered at T-12; another radicular artery entered at T-4. We concluded that the spinal cord ischemia was caused by the interruption of the radicular artery at T-4 and that the segments nourished by the blood flow of the artery of Adamkiewicz were intact. We suggest that in some patients important radicular arteries other than the artery of Adamkiewicz are essential to preserve blood flow to the upper or middle thoracic spinal segments.  相似文献   
67.
Tissue renin content within the kidney decreases from outer to inner cortex. However, it is not known whether this gradient is due to a decrease in the number of afferent arterioles from the outer to inner cortex or the decrease in renin content per afferent arteriole. Furthermore, it is still controversial whether sodium depletion increases or decreases this gradient. According to Taugner et al., sodium depletion induces the extension of renin positive part of afferent arterioles from vascular pole toward interlobular artery. Since the length of extension may differ among superficial, midcortical, and juxtamedullary afferent arterioles, the observed gradient may vary depending on whether the entire afferent arteriole or only the vascular pole is examined. In the present study, we microdissected the entire afferent arterioles from superficial, middle, and juxtamedullary cortex of rabbit kidney, and examined tissue renin content. We studied: 1. whether tissue renin content per afferent arteriole decreases from the outer to inner cortex. 2. whether sodium depletion affects the gradient of tissue renin content within the cortex. In result, we reached the conclusions, as follows: 1. Tissue renin content per afferent arteriole decreases steeply from superficial to midcortical to juxtamedullary afferent arterioles. 2. The absolute difference in renin content among the three types of afferent arterioles becomes greater during sodium depletion. The internephron heterogeneity of tissue renin content may contribute to functional heterogeneity.  相似文献   
68.
A clay film was made of the stone powder and water drops on a slide glass and dried at 100 to 110 degrees C or at room temperature in the horizontal position for 20 calcium oxalate stones which had been received between April, 1978 and August 1980. Each clay film was scanned with an X-ray diffractometer using CuK alpha radiation, stored at room temperature in a wooden sample case and analysed again by X-ray five to seven years after the first X-ray analysis. Then the recent diffractograms of 20 powder samples were compared with the previous ones regarding the peak heights at 14.2 degrees, 14.8 degrees and 25.8 degrees (2 theta), which were considered representative of weddellite, whewellite and apatite contents and designated as Iwe, Iwh and Iap, respectively. Since there was a good correlation between Iwe/Iwe + Iwh + Iap and weddellite/weddellite + whewellite + apatite that was determined by thermogravimetry (Fig. 1), the transformation rate of weddellite to whewellite can be expressed as the change of Iwe/Iwe + Iwh + Iap. One sample Iwe/Iwe + Iwh + Iap of which decreased by 48% in seven years (Fig. 3) and another sample Iwe/Iwe + Iwh + Iap of which increased by 10% in five years (Table) were excluded from this study because the clay films of these samples might have been overheated or incompletely dried before the first X-ray analysis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
69.
Clinical usefulness of the WHO histological classification of thymoma.   总被引:12,自引:0,他引:12  
PURPOSE: Rosai et al. published the World Health Organization (WHO) classification of thymic epithelial tumors in 1999, and its clinical usefulness seems to be established. It is our purpose to find the clinically relevant diagnostic points in the WHO Histological Classification of Thymoma. METHODS: Thymomas surgically removed from 100 consecutive patients at Juntendo University Hospital between October 1983 and February 2002 were classified according to the WHO histological classification. We assessed overall survival and recurrence-free rate calculated for each tumor type in the WHO classification compared with those of tumors classified by the Masaoka system. RESULTS: The thymic epithelial tumors in this series comprised 10 type A, 15 type AB, 18 type B1, 21 type B2, 33 type B3, and 3 type C tumors according to the WHO classification. Based on the Masaoka system, the disease was stage I in 53 patients, stage II in 30, stage III in 15, and stage IV in 2. The 15-year recurrence-free rate was 100% for type A, AB and B1, while the rates for types B2 and B3 were 66.7% and 54.5%, respectively. The 10-year recurrence-free rate was 66.7% for type C. The 15-year recurrence-free rate of the 64 patients with type A, AB, B1, and B2 thymomas was significantly higher from that of the 33 patients with type B3 thymoma (p=0.0026). CONCLUSION: When using the WHO classification, it is critical to distinguish type B3 thymoma from other tumor types.  相似文献   
70.
K Abe  M Ohta 《Psychopathology》1992,25(4):218-228
Published cases of periodic psychosis of puberty and related papers were reviewed. The clinical picture is near-monthly recurrence of episodes of stupor or excitement lasting about 1 or 2 weeks, which are accompanied by delusion and in some cases also by hallucinations or confusion. This condition was found to occur more commonly in girls than in boys, and in half of the girls reported the episodes tended to start a few days before menses. Adolescents with mental retardation were more commonly affected, and this suggests that organic brain damage may play a role in the etiology in some cases. Short-term prognosis is usually favorable, but at long-term follow-up, nearly half of them were found to be suffering from affective or schizophrenic illness. The clinical importance of recognizing this psychosis early in the course of illness is emphasized.  相似文献   
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