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91.
We have studied the kinetics and specificity of the cytotoxic T lymphocyte (CTL) response to influenza A/PR/8 (H1N1) virus pulmonary infection in the mouse detected using spleen cells from infected mice which were stimulated in bulk and limiting dilution cultures. A hybrid protein designated D-peptide, which contains the terminal 157 amino acids of the HA2 subunit of A/PR/8 virus, was used to stimulate influenza virus subtype-specific secondary CTL in vitro. Infection induced two specificities of precursor CTL, cross-reactive and subtype-specific. The kinetics of the subtype-specific CTL response detected by the D-peptide were similar to the cross-reactive CTL response detected by stimulation with live virus. The majority of the precursor CTL (CTL-p) are able to lyse virus-infected target cells in a cross-reactive fashion. The number of memory subtype-specific and cross-reactive CTL increased by approximately 2.5 logs10 during the first 3 weeks after infection. 相似文献
92.
93.
Toshio Mizutani Ken-ichi Nakamura Mutsuo Enomoto Masuhiro Sakata Shigeo Yamada 《Neuropathology》1998,18(1):80-90
A neuropathological study on 1540 consecutive autopsy brains ranging from 60 to 107 years of age revealed the following points. (1) Of the of the demented cases of the plaque-predominant type, 93% were complicated with multiple tiny cortical infarcts. They showed a tendency for dementia to develop before or after the appearance or worsening of a systemic disorder such as cardiovascular disease, respiratory infection and cancer. However, there was no case showing Alzheimer-type dementia (ATD). (2) The plaque-predominant type might be an extreme condition of brain aging in terms of senile plaques (SP). It is likely that although the pathological appearance of SP alone is not responsible for dementia, its coexistence with multiple cortical infarcts could be the cause of dementia. Therefore, this type should be distinguished from ATD. (3) Primary hippocampal degeneration could also be an extreme condition of brain aging in terms of neurofibrillary tangles. This condition was different pathologically from the hippocampal lesion in ATD. (4) Several characteristics of old-old and oldest-old patients were clarified. 相似文献
94.
Masataka Nagao Wei-dong Zhang Yoshiyuki Itakura Masahiko Kobayashi Yoshihiro Yamada Katsunori Yagi Tsuneaki Oono Takehiko Takatori 《International journal of legal medicine》1993,106(3):142-144
Summary The dynamics of paraquat in the stomach and esophagus of rats were demonstrated using immunohistochemical techniques. The Rats were killed 3 h, 12 h, 24 h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In the stomach, paraquat was localized in the epithelial cells between 24h and 10 days after injection, whereas in the esophagus, paraquat was localized in epithelial cells and the lamina propria mucosa between 12 h and 10 days after administration. Although these findings were similar to those observed in the intestine of rats, no clear changes in the distribution of paraquat with time were observed; suggesting that the stomach and esophagus are important reservoirs for the redistribution of paraquat. 相似文献
95.
T Nagaoka D D Walker P J Seaba T Yamada 《Electroencephalography and clinical neurophysiology》1992,84(6):473-476
When two potentials having large amplitude differences are simultaneously recorded, the large amplitude potential contaminates the small amplitude response. The small, early potentials generated by this contamination resemble far-field potentials. Although scalp-recorded SEP was contaminated by waves similar to the peripheral potential, peak latencies and wave form were not identical. Experiments simulating the recording situation verified the presence of "cross-talk." Capacitive coupling would shift peaks and alter the wave forms. Other possible mechanisms for the cross-talk and methods of minimizing it are offered. One should be cautious interpreting the results when potentials of large amplitude differences are simultaneously recorded. 相似文献
96.
T Yamada T Saito Y Matsue Y Honda T Fuchigami M Fujii M Ross 《Electroencephalography and clinical neurophysiology》1992,84(6):492-498
Using a conditioning-test paradigm, we studied the recovery function of tibial nerve somatosensory evoked potentials (SEPs) conditioned by preceding peroneal nerve stimulation. The inter-stimulus intervals (ISIs) ranged from 0 to 400 msec, where 0 msec indicated simultaneous arrival of tibial and peroneal nerve volleys at the L1 spine. The recovery curve was W-shaped, showing two peaks of SEP suppression, maximum at 6 msec ISI (1st phase) and 50-75 ISI msec (2nd phase). In the 1st phase suppression, we found distinct differences in wave forms between 0-2 msec ISI and 4-6 msec ISI. At 0-2 msec ISI, P40-N50-P60 amplitude decreased and latencies shortened, while P31 and N35 were unchanged. At 4-6 msec ISI, all peaks, possibly excluding P31, were markedly depressed. We attribute the former change to an "occlusive effect" and the latter to an "inhibitory effect," each mediated via a central synaptic network between the two nerves. The attenuation of the 2nd but not the 1st phase suppression by peroneal nerve block distal to the stimulating electrodes provided evidence that the 2nd phase suppression resulted primarily from interfering afferent signals generated by peroneal nerve peripheral receptors, activated by foot movement. 相似文献
97.
We presented a report on four cases of juvenile parkinsonism with a marked diurnal fluctuation of symptoms and dystonia. Among parkinsonian signs, rigidity fluctuated the most and increasing rigidity by passive or active movements or emotional stress was observed. When we analyzed patients previously reported, in addition to our own new patients, apart from the diurnal fluctuation and predominant occurrence in females, many similarities to Yokochi's third group of juvenile parkinsonism were found. In the previous reports, the patients with the marked fluctuation of parkinsonian symptoms have not always shown dystonia. The changes of symptoms in relation to menstruation and pregnancy were other characteristic features in our three female patients. Here we proposed that for the present, it is preferable to call this disorder "juvenile parkinsonism with a marked diurnal fluctuation." 相似文献
98.
Suzuki Hisamitsu; Ota Kazuo; Ohno Ryuzo; Masaoka Toru; Shibata Hirotoshi; Kimura Ikuro; Amaki Ichita; Miura Yasusada; Uzuka Yoshiro; Kawato Masafumi; Shirakawa Shigeru; Hirota Yutaka; Maekawa Tadashi; lmai Kuniyuki; Takaku Fumimaro; Shimoyama Masanori; Kitahara Takeshi; Oguro Masao; Kozuru Mitsuo; Kawagoe Hiroya; Nakamura Toru; Yamada Kazumasa 《Japanese journal of clinical oncology》1989,19(4):338-347
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 19711975 to 62.3%during 19811985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 19711975and 69.7% during 19811985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 3740 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe. 相似文献
99.
100.
The thermoelasticity in rigor muscle was investigated using chemically skinned frog sartorius muscles. The use of chemically skinned muscles enabled us to study the thermoelasticity under various intracellular circumstances. Effects on the thermoelasticity of the presence or the absence of Ca and the lowering of pH in the rigor solution were investigated. All values of the thermoelastic heat: tension ratios obtained under various circumstances were within the range reported for active muscles. In rigor state, the cross-bridges are fixed on the thin filaments and head can no longer rotate. Hence the present results indicate that the thermoelasticity in active muscles originates from the thermoelasticity of the myofilaments or the cross-bridges. 相似文献