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151.
Previous ablation studies have suggested that area 19 of the cat plays an important role in pattern discrimination. To clarify the functional roles unique to area 19, we studied the receptive-field properties of cells in area 19 and compared them with those of cells in area 17. Recordings were made of anesthetized and immobilized animals. The majority (72%) of the cells in area 17 responded maximally to an elongated bar at a particular orientation, while they responded only weakly or not at all to a small spot (elongation-requiring cells). In contrast, more than half (63%) of the cells in area 19 showed a good response to a nonoriented small stimulus moving in any direction (dot-responsive cells). Two-thirds of the dot-responsive cells in area 19 failed to respond when the moving slit was elongated to more than some length in any orientation. These dot-responsive cells of the "inhibited-by-length" type responded strongly to the end of a long bar, and many of them also responded strongly to a break point in the middle of a long bar. We suggest that these dot-responsive cells of the "inhibited-by-length" type detect discontinuities in contours. Though they are in the minority, elongation-requiring cells constitute a considerable population (37%) in area 19, and dot-responsive and elongation-requiring cells from columnar patches in the same area. We conclude that, in contrast to area 17, whose main role is the decomposition of patterns into oriented contours, area 19 analyzes both orientation and discontinuities, with a strong bias towards the latter. 相似文献
152.
Osamu Ozaki M.D. Kunihiko Ito M.D. Kaoru Kobayashi M.D. Akira Suzuki M.D. Yoshitaka Manabe M.D. Yasuhiro Hosoda M.D. 《World journal of surgery》1988,12(4):565-571
Familial occurrence of differentiated, nonmedullary thyroid carcinoma in 23 patients from 11 families is reported. Five patients were male and 18 were female. The familial relationship of patients was parent and child in 12 cases from 6 families, and siblings in 11 cases from 5 families. Carcinoma of other organs was noted in other members in 8 families. Histological examination revealed 18 papillary, 2 follicular, and 2 anaplastic carcinomas (the 2 anaplastic carcinomas were considered to be transformed from preexisting differentiated carcinoma). In 1 case, the histological type was unknown. The average diameter of the primary lesion was 29.9 mm. Cervical lymph node metastasis was found in 77.8% and local recurrence in 28.6% of the patients. Solid and invasive growth was dominant. On HLA typing, phenotypes of B7 and DR1 were significantly redominant in familial patients compared with nonfamilial patients and normal Japanese. Moreover, the haplotype of B7-Cw7-DR1 was observed in 5 of 13 patients tested.
It is suggested from these observations that some types of differentiated, nonmedullary thyroid carcinoma may show familial occurrence and that they may have common factors with regard to the genetic and immunologic basis of the disease.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987. 相似文献
Resumen Se informa la ocurrencia familiar de carcinoma bien diferenciado, no medular, de tiroides en 23 pacientes provenientes de 11 familias, 5 hombres y 18 mujeres. La relación familiar fue padre e hijo en 12 casos de 6 familias, y hermanos en 11 casos de 5 familias. Se observé la presencia de carcinoma de otros órganos en otros miembros de 8 familias. El examen histopatológico reveló 18 carcinomas papilares, 2 foliculares, y 2 anaplásicos (los 2 fueron considerados como transformación de carcinomas diferenciados preexistentes). En un caso no fue conocido el tipo histológico. El diámetro promedio de la lesión primaria fue 29.9 mm. Se hallaron metástasis en ganglios cervicales en 77.8% de los pacientes y recurrencia local en 28.6%. El crecimiento sólido e invasivo apareció como característica dominante. En la tipificación HLA aparecieron como significativamente predominantes los fenotipos de B7 y DR1 en pacientes familiares en comparación con pacientes no familiares y japoneses normales. Por otra parte, el halotipo de B7-CW7-DR1 fue observado en 5 de 13 pacientes investigados.Como resultado de estas observationes se sugiere que algunos tipos de carcinomas diferenciados, no medulares, pueden demostrar ocurrencia familiar y que pueden poseer factores comunes relacionados con las bases genéticas e inmunológicas de la enfermedad.
Résumé On a étudié les caratéristiques du cancer de la thyroïde, dans sa variété différenciée non médullaire, survenu chez 23 patients provenant de 11 familles. Cinq patients étaient des hommes, 18 des femmes. La relation familiale était parent/enfant dans 12 cas provenant de 6 familles, et frère/soeur dans 11 cas provenant de 5 familles. Des membres de 8 autres familles présentaient un cancer d'un autre organe. Il y avait 18 cancers papillaires, 2 cancers folliculaires, et 2 cancers anaplasiques (on a considéré que les 2 cancers anaplasiques étaient des transformations à partir de cancers différenciés préexistants). Dans un cas, le type histologique était inconnu. Le diamètre moyen de la lésion primitive était de 29.9 mm. On a retrouvé des métastases ganglionnaires cervicales chez 77.8% des patients et une récidive locale chez 28.6%. Les tumeurs étaient principalement solides et invasives. Par rapport aux cancéreux non familiaux et à la population japonaise normale, il y avait plus de phénotypes B7 et DR1 au système HLA. L'haplotype B7-CW7-DR1 était observé chez 5 des 13 patients testés.On suggère que certains types de cancer différenciés, non médullaires, ayant des facteurs communs génétiques et immunologiques, peuvent survenir dans une même famille.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987. 相似文献
153.
The variations of sublingual temperature, pulse rate, flicker fusion frequency (CFF), subjective fatigue feelings (SFF) and 8 selected reaction times and the relationships between them were examined in six university students under the condition of successive 6-h delayed shift with 8 sleeping h and 22 waking h for 6 d. SFF was measured by the scales proposed by the Japanese Society for Industrial Fatigue Research. On the 2nd d when the shifting was started after the subjects had slept from 00:00 to 08:00 and on the 3rd d after sleeping h of 06:00 to 14:00, the variations of sublingual temperature, pulse rate and CFF showed a pattern of circadian rhythm. However, on the 4th-5th d the rhythms of sublingual temperature and pulse rate were flattened. On the other hand, CFF demonstrated a variation of having a nearly constant tendency till 08:00, followed by a gradual decrease during the daytime. The variation of SFF (the scale of "sleepiness and dullness") was similar to that of CFF, although the change of the score was in the opposite direction. On the 3rd-4th d, the 4th-5th d and the 6th d, significantly high rank correlations were observed between sublingual temperature and pulse rate and between CFF and SFF. However, between sublingual temperature and CFF, a high correlation which was observed on the 1st and the 2nd d was not seen on the 4th-5th and 6th d. Eight selected reaction times were shortened during the experimental days, but there was no consistent pattern of variation within these days. The results of the experiment showed that the relationship between CFF and SFF exists during the daytime when the arousal level is low. 相似文献
154.
M. Shibuya F. Saito T. Miwa R. L. Davis C. B. Wilson T. Hoshino 《Acta neuropathologica》1992,84(2):178-183
Summary The growth potential of 65 pituitary adenomas was determined by histochemical analysis with Ki-67 and anti-DNA polymerase monoclonal antibodies, bromodeoxyuridine (BrdUdR) labeling, and counts of argyrophilic nucleolar organizer regions (Ag-NORs). The mean proliferating cell indices (PCIs) determined by Ki-67 and anti-DNA polymerase and the BrdUdR labeling index (LI) were generally very low [1.0±0.2%, 1.1±0.2%, and 0.5±0.1% (±SE), respectively]. Apart from adrenocorticotropic hormone-positive adenomas, which had significantly higher indices, there were no statistically significant differences in the indices among the other subtypes of pituitary adenomas. Recurrent tumors had higher Ki-67 and DNA polymerase PCIs and BrdUdR LIs (3.6%, 4.2%, 1.4%) than primary tumors (0.8%, 0.8%, 0.3%; P<0.005). The number of Ag-NORs did not correlated significantly with any of the three indices. The mean number of Ag-NORs was higher in nonfunctioning adenomas than in functioning adenomas (2.04 vs 1.66, P<0.005); among prolactin-positive adenomas, those treated preoperatively with bromocriptine had more Ag-NORs than untreated tumors (1.75 vs 1.57, P<0.005). These results suggest that the Ki-67 and DNA polymerase PCIs and the BrdUdR LI predict the growth potential of individual pituitary adenomas, whereas the number of Ag-NORs appears to correlate with hormone production rather than with the proliferative potential.Supported by grants CA-13525 and CA-50210 from the National Cancer Institute, by a grant from the Phi Beta Psi Sorority, and by Grant-in-Aid A 63771083 from the Ministry of Education, Science, and Culture of Japan 相似文献
155.
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
156.
Isolated angitis of the central nervous system (IACNS) is rare condition with inflammation limited to vessels supplying the brain. This IACNS has been a poorly characterized and infrequently reported illness since it was first described as a separate entity in 1959. However, a patient with IACNS has not been reported in Japan. A patient, 39-year old-male, with IACNS limited to small and middle vessels is described. Recurrent, transient consciousness disturbances, focal myoclonus, papilloedema and temporal lobe epilepsy were observed during disease course. CSF finding of this patient showed lymphocytosis with marked increased protein. Carotid and vertebral angiogram showed irregular luminal outline in branches of all arteries. The most specific finding is that of alternating areas of focal stenosis and ectasia giving a "sausage" pattern. These characteristic findings showed in the branch of external carotid arteries. There was no evidence of systemic vasculitis by systemic angiography. Biopsy of temporal artery showed lymphocyte infiltration, fibrinoid necrosis without giant cell and granuloma. Formation of A-V malformation in the branch of external carotid artery was also observed. This histopathological finding was compatible with necrotizing angitis, not granulomatous angitis. Isolated angitis of the central nervous system was diagnosed. In spite of his administration of corticosteroid, cerebrospinal fluid abnormalities has not responded markedly. Abnormal findings of carotid and vertebral angiogram also has not changed. After 7 years from his onset, his neurologic signs and symptoms were well controlled with administration of anti-epileptic drugs. 相似文献
157.
Prevalence of depressive symptoms in a Japanese occupational setting: a preliminary study. 总被引:4,自引:2,他引:2 下载免费PDF全文
We measured the prevalence of depressive symptoms in 2,190 Japanese tax office workers using the Japanese version of the Center for Epidemiologic Studies Depression Scale (CES-D). Score distribution by sex was more symmetrical and the mean score of each sex was higher than in the United States population. A high level of depressive symptoms was found in 15.2 percent of males and 10.6 percent of females by controlling for age and marital status. Males aged 50 years and over had more depressive symptoms than other male age groups. Perceived stress, related both to family life and the workplace, was associated with a high level of depressive symptoms. "Long-distance marriage" ("business bachelorhood"), peculiar to Japanese occupations, had little influence on depressive symptomatology. 相似文献
158.
159.
Kitajima T Kanbayashi T Saito Y Takahashi Y Ogawa Y Sugiyama T Kaneko Y Aizawa R Shimizu T 《Neuroscience letters》2004,355(1-2):77-80
It is known that benzodiazepines have a hypotensive effect, but the mechanism has not been well elucidated yet. To clarify whether this effect is due to central or peripheral mechanism, we administered 5 mg of diazepam or saline intravenously to healthy volunteers and assessed the change in blood pressure, heart rate, muscle sympathetic nerve activity and heart rate variability. After diazepam administration, systolic and mean blood pressure decreased significantly. Muscle sympathetic nerve activity was also significantly reduced but heart rate did not change, whereas the variables of spectral analysis of heart rate variability did not show significant change. We concluded that the hypotensive effect of diazepam in human is mainly due to the central mechanism. 相似文献
160.
Rye leaves infected with soil-borne wheat mosaic virus isolate US-A at six consecutive developmental stages were examined with the electron microscope. Virus was not detected in leaves shorter than 5 mm, and viral inclusions were first observed in leaves 10–30 mm in length. The inclusions consisted of tangled tubules or smooth-surfaced endoplasmic reticulum and contained virus rods scattered in interstices between the tubules. The inclusions enlarged with the growth of leaves and changed to a looser conformation. In leaves longer than 100 mm, inclusions were mostly disintegrated and aggregates of virus rods appeared in the cytoplasm and vacuole. In such leaves, inclusions consisted of concentrically arrayed membranes with virus rods sandwiched in between. Both types of inclusions were also found in wheat and barley leaves infected with the US-A isolate. 相似文献