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71.
T. Hamada T. Sasaguri A. Tanimoto Y. Sasaguri M. Hisaoka H. Hashimoto K. Hirakata H. Nakata 《Virchows Archiv : an international journal of pathology》1995,426(6):597-602
We evaluated a novel method of computed tomography (CT) analysis using formalin-fixed lungs of autopsy cases with mild emphysema. Eight formalin-inflated lungs (FILs) obtained at autopsy were examined using CT after draining off the formalin and air inflation with an air pump, and subjected to pathological study including pathological scoring of emphysema and microscopic image analysis (MIA). Satisfactory CT examination was carried out within 5 h of lung fixation. The mean alveolar area determined by MIA correlated highly with the lung volume (r=0.845) and CT score (r=0.722). This method is simple compared with conventional polyethylene glycol fixation for CT and enables CT examination of resected lungs without anxiety about biohazards. Mild emphysema can be detected by MIA. 相似文献
72.
The purpose of this study was to determine whether ES-242-1, a novel N-methyl-D-aspartate (NMDA) receptor antagonist of microbial origin, has anti-nociception at the spinal level and to evaluate how its anti-nociceptive effect differs from that of MK-801, a non-competitive NMDA receptor antagonist. Agents were injected intrathecally (0.1, 1.0 and 10 microg) through a previously implanted PE tube in rats. Formalin (2%, 100 microl) was injected subcutaneously into the left hindpaw 15 min after each antagonist administration. Licking time as a nociceptive behavior was measured in three stages after formalin-injection, such as early phase (0-9 min), late first phase (10-29 min) and late second phase (30-60 min). In the early phase, the largest dose of ES-242-1 significantly decreased total licking time, although MK-801 did not show any significant reduction. With the treatment of 1.0 and 10 microg MK-801, total licking time in both late first and second phases was significantly suppressed, although the smallest dose (0.1 microg) of ES-242-1 showed a significant reduction in the late second phase. These results indicate that ES-242-1 is highly effective against tonic pain, such as inflammatory pain. 相似文献
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75.
M Suneya M Onuma S Yamamoto K Hamada S Watarai T Mikami H Izawa 《Journal of comparative pathology》1984,94(2):301-309
Five sheep were experimentally inoculated with BLV in order to study the humoral immune response in animals infected with bovine leukaemia virus (BLV). During experimental periods of 46 months, 2 sheep died with leukaemia and one sheep showed splenomegaly and proliferation of tumour cells. The other 2 sheep were clinically normal. All of the inoculated sheep developed antiviral antibodies 1 month after inoculation and BLV could be re-isolated in lymphocytes 2 to 3 months after inoculation. Antibody against glycoprotein antigen (gp51) of BLV appeared earlier than the antibody against protein antigen (p24) and antibody titres of the former were higher than those of the latter during the course of the experiment. The complement dependent antibody cytotoxicity test was performed for the detection of antibody against BLV-related cell membrane antigen with 2 different kinds of target cells; FLK cells which are foetal lamb kidney cells chronically infected with BLV and SF-28 cells which are sheep fibroblasts transformed with BLV in vitro. All 5 sheep developed cytotoxic antibodies against both types of cells. In sera from two leukaemic sheep, cytotoxic antibody titres against SF-28 cells gradually decreased 30 months after inoculation and finally became negative one to 3 months before they died of leukaemia. However, these leukaemic sheep persistently produced antibodies against gp51 and p24. 相似文献
76.
Shibagaki N Hanada Ki Yamashita H Shimada S Hamada H 《European journal of immunology》1999,29(12):4081-4091
We previously demonstrated that CD82, expressed on both T cells and antigen-presenting cells (APC), plays an important role as a co-stimulatory molecule especially in the early phase of T cell activation. We also showed that the CD82 expression level is up-regulated on activated T cells and memory T cells. This up-regulation enhances both T cell-T cell and T cell-APC interactions. In this study, we further investigated the mechanism of CD82-mediated cell-cell adhesion. The enhanced adhesion between CD82-overexpressing Jurkat cells was completely blocked by anti-ICAM-1 / LFA-1 monoclonal antibodies. Increased interaction of LFA-1 with ICAM-1 was further confirmed by enhanced adhesion of CD82-overexpressing Jurkat cells to immobilized ICAM-1-Ig. CD82 co-immunoprecipitated with LFA-1 from Jurkat cells and CD82 and LFA-1 colocalized at an adhesion foci. These results suggest that the T cell stimulation via anti-CD3 cross-linking or phorbol myristate acetate treatment up-regulates CD82 expression, leading to the colocalization of CD82 and LFA-1, and results in enhanced interaction between LFA-1 and ICAM-1. In addition, a blocking experiment using monoclonal antibodies suggested that CD82 and LFA-1 molecules on APC are also important for the optimal activation of T cells. This is the first report that describes the enhancement of cell-cell interaction through LFA-1 and ICAM-1 by the overexpression of another cell surface molecule, CD82. 相似文献
77.
Salama SA Au WW Hunter GC Sheahan RG Badary OA Abdel-Naim AB Hamada FM 《Environmental and molecular mutagenesis》2002,40(3):153-160
Atherosclerosis (AR) is the leading cause of morbidity and mortality in the US and cigarette smoking is a major contributing factor to the disease. Like cigarette smoking in lung cancer, genetic susceptibility may be an important factor in determining who is more likely to develop AR. However, the current emphasis has been on susceptibility based on altered cardiovascular homeostasis. In this investigation, we studied 120 AR patients and 90 matched controls to elucidate the association between polymorphisms in some metabolizing genes (GSTM1, GSTT1, CYP2E1, mEH, PON1, and MPO) and susceptibility to AR. We found that the GSTT1 null allele and the fast allele of mEH(*) (exon 4) are associated with risk for AR. Furthermore, the combined genotypes GSTM1 null/ CYP2E1(*)5B, GSTM1 null/mEH YY, and GSTT1 null/mEH YY are significantly associated with susceptibility to AR (OR = 15.42, 95% CI = 1.33-77.93, P = 0.021; OR = 3.48, 95% CI = 1.63-8.04, P = 0.0008; OR = 3.4; 95% CI = 0.99-17.38, P = 0.05; respectively). We have also conducted cytogenetic analysis to elucidate if induction of chromosome aberrations (CAs) is a biomarker of AR susceptibility. We found that among cigarette smokers (AR patients and smoker controls), individuals having the GSTM1 null allele had a significantly higher frequency of CAs compared to those with the normal allele (P < 0.05). This association was not found among nonsmokers. In addition, individuals who had inherited the CYP2E1(*)5B allele exhibited a significantly higher CA frequency (8.0 +/- 0.82) compared to those with the CYP2E1 wild-type genotype (4.31 +/- 0.35). Since the analysis of genetic susceptibility factors is still in its infancy, our study may stimulate additional investigations to understand the roles of genetic susceptibility and cigarette smoking in AR. 相似文献
78.
The neuronal activity in the motor cortex of the rhesus monkey was investigated in three different tasks performed with finger, wrist, and arm movements. A total of 125 neuronal activities were analysed. They were classified into five groups in terms of muscular contractions provoked by intracortical stimulation; neurons related to contractions of finger, wrist, elbow, shoulder, or trunk muscles. The neuronal activities in three tasks performed with finger, wrist, or arm movements were investigated for each group. Most of the neurons related to the contractions of elbow, shoulder, or trunk muscles were associated solely with arm movement. Smaller numbers of neuronal activities changed their firing frequencies in association with two or three tasks. Neurons related to the contractions of finger and wrist muscles showed various firing patterns in the three tasks; some responded to a single task with wrist or arm movement, while others changed their activities in association with more than one task. The presence of multi-task related neurons is discussed with respect to the multisegmental termination of corticospinal axons in the spinal cord. 相似文献
79.
80.
During three different motor tasks of finger, wrist and arm movements on either side, 80 pyramidal tract neuron (PTN) activities were recorded in the monkey motor cortex. They were divided into three groups; PTNs related to controlateral movement (contra-PTNs), those related to ipsilateral movementt lateral movement (bilaterai-PTNs) and those related to ipsilateral movement (ipsi-PTNs). The latency histogram of the antidromic activation was similar for contra-PTNs as well as ipsi- and bilateral-PTNs in the fast PTN group, but most of slow PTNs appeared among contra-PTNs. Intracortical microstimulation (ICMS) was delivered to correlate muscular contraction with PTN acticity. Most of slow PTNs were related to proximal muscular contraction and PTNs related to proximal muscles appeared more in ipsi- and bilateral-PTNs than in contra-PTNs. 相似文献