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21.
[3H]Flunitrazepam (FNZ) binding sites were characterized in homogenates of cat visual cortex during normal postnatal development and following dark rearing from birth. In parallel experiments, the distribution and density of [3H]FNZ binding sites were examined by in vitro autoradiographic or 'scrape' methods. In homogenates, Bmax measurements showed low early values, rising to a peak in receptor density at about 60 days postnatal, followed by a decline in adulthood. At all ages, gamma-aminobutyric acid (GABA) altered the Kd, but not the Bmax of [3H]FNZ binding sites. Kd values showed a general increase with age, parallelled by an increased sensitivity to GABA. Receptor autoradiography revealed that the highest density of [3H]FNZ binding sites was in layer IV of cats of all ages. Deafferentation of extrinsic inputs to the visual cortex by surgical undercutting did not alter this pattern of laminar distribution, indicating that the receptors were associated with intrinsic cortical elements rather than subcortical inputs. Dark rearing had no effect on [3H]FNZ laminar distribution in the visual cortex. The Bmax was higher at 30 days postnatal, but did not differ significantly thereafter. Modulation by GABA was concomitantly higher at 30 days, but lower than normal in dark-reared animals at ages greater than 30 days postnatal. The results are discussed in relation to the normal and abnormal development of GABA receptors in the cat visual cortex. 相似文献
22.
Solitary fibrous tumors (SFT) have recently been established to be of mesenchymal origin. Although there are numerous reports
of SFTs arising from the pleura, reports of the tumor arising from extrapleural sites are comparatively rare [Fletcher CDM,
Unni K, Mertens F (eds) World Health Organization classification of tumors, pathology & genetics, tumors of soft tissue and bone. IARC Press, Lyon, pp 86–901, 2002]. We report a case of SFT arising in the inguinal region. 相似文献
23.
24.
Nucleolar organizer regions in meningioma 总被引:1,自引:0,他引:1
Seventy-eight cases of meningioma and related tumors were examined independently using a simple and reproducible argyrophilic method for the demonstration of nucleolar organizer regions (AgNORs) and staining with bromodeoxyuridine monoclonal antibody. The mean number of AgNORs per cell and the bromodeoxyuridine labeling index were shown to be linearly related (r = 0.84, P less than 0.001). The mean AgNOR number was 2.99 for meningeal sarcoma, 2.29 for anaplastic meningioma, 2.08 for hemangiopericytic meningioma. 1.72 for recurrent meningioma without atypical histological findings, and 1.52 for nonrecurrent meningioma. We noted that the mean number of AgNORs reflected the cellular kinetics of a tumor and was related to histological grade and clinical behavior. 相似文献
25.
Kazumichi Yamada Satoshi Goto Taro Oyama Makoto Yoshikawa Shinji Nagahiro Yukitaka Ushio 《Acta neuropathologica》1995,89(2):172-177
The present study concerns the vulnerability of striatal interneurons immunopositive for the Ca2+-binding protein calretinin to ischemic neuronal injury. An immunohistochemical study was carried out on the striata of rats which had undergone transient middle cerebral artery occlusion. Two weeks after the ischemia, there was a marked reduction in the number of calretinin-positive neurons in the ipsilateral ischemic lesion, although the striatal interneurons positive for parvalbumin, which are a neuronal population distinct from the calretinin-immunoreactive cells in the striatum, were spared in the insulted areas. The present data indicate that the striatal calretinin-positive neurons are less resistant to transient ischemia, suggesting that there may exist vulnerability differences among the striatal interneurons in ischemia-induced neuronal injury. 相似文献
26.
Among diseases due to cerebral parasitism, that caused by Sparganum mansoni, the larva of Spirometra mansoni, is very rare. We have encountered two such cases. A computed tomography scan in both revealed a nodular high density contrast enhanced area against an extensive low density background area. Neither calcification nor cyst formation was recognized. These computed tomography scan findings were thought to be characteristic for cerebral sparganosis mansoni and were difficult to differentiate from those of a cerebral tumor. In both cases, definitive diagnosis was achieved by identification of the worm after excision of the lesion. The best treatment for cerebral sparganosis mansoni is surgical excision of the lesion, and in the two cases presented the postoperative outcome was good. 相似文献
27.
28.
Substance P- and calcitonin gene-related peptide-immunofluorescent nerves in the repair of experimental bone defects 总被引:3,自引:0,他引:3
Summary Healing of an experimental bony defect in the rat's tibia was studied with an immunofluorescent technique to clarify when and where substance P (SP) and calcitonin gene-related peptide (CGRP) would develop. The normal tibia showed a few SP- and CGRP-immunofluorescent nerve fibres. In the experimental tibia, the number of these fibres increased on the 6th day after operation, reached a peak of proliferation on the 15th day and reverted to normal after the 24th day. The changes were associated with the development and decay of callus tissue suggesting that harmful stimuli from the injured site in a bone could be mediated by sensory nerves throughout the repair period. Most of the SP- and CGRP-immunofluorescence was seen near the vessels, frequently in the same nerve fibres. The SP- and CGRP-immunofluorescent nerves seemed to take part jointly in callus formation through the enhancement of local blood flow.
Résumé Le procesus de guérison d'une perte de substance osseuse expérimentale a été étudié sur le tibia du rat par immunofluorescence afin de déterminer quand et où la substance P (SP) et la calcitonine peptide d'origine génique (CGRP) se développeraient. Le tibia normal ne montre qu'un petit nombre de fibres nerveuses immunofluorescentes SP et CGRP. Dans le tibia d'expérimentation, les fibres nerveuses immunofluorescentes SP et CGRP augmentent en nombre à partir du 6ème jour, atteignent leur maximum de prolifération le 15ème jour et reviennent à l'état normal après le 24ème jour post-opératoire. Ces modifications sont étroitement associées au développement et à la disparition du cal, suggérant ainsi que les stimuli nocifs provenant de la lésion osseuse pourraient être inactivés par les nerfs sensitifs durant la période de réparation. En outre, la plus grande partie de l'immunofluorescence SP et CGRP a été observée à proximité des vaisseaux, souvent dans les mêmes fibres nerveuses. Il semble que les nerfs immunofluorescents SP et CGRP participent conjointement à la formation du cal en augmentant la vascularisation locale.相似文献
29.
M Imamura H Aoki H Uchida H Kubota T Murakami 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(6):502-504
Ruptured aneurysm of the sinus of Valsalva is a rare cardiac lesion. A ruptured aneurysm of the sinus of Valsalva in the right ventricle of a 64-year-old man was successfully repaired. The patient was admitted to the hospital with high fever and chest oppression. Diagnosis was made by two dimensional echocardiography, cardiac catheterization, and cardiac angiography. An aortotomy, main pulmonary arteriotomy, and right ventriculotomy were performed. There was no VSD, and the aneurysm originated from the right coronary sinus, rupturing into the right ventricle inlet portion. The ruptured aneurysm of the sinus of Valsalva was closed with a Dacron patch from inside the aorta. He is doing well after surgery. There was no heart murmur. CTR decreased and pulmonary blood flow fell to a normal value. As far as we know, this patient is the second oldest patient in Japan with surgical repair. 相似文献
30.
Changes in the levels of urea cycle enzymes and polyamine metabolism in the liver of rats treated with alpha-naphthylisothiocyanate (ANIT), an inducer of experimental cholestasis, were studied. Activities of arginase increased approximately two-fold compared to the control values during the period of 24-72 hours after oral administration of ANIT (100 mg/kg), while activities of ornithine carbamyltransferase and ornithine aminotransferase decreased. The activity of ornithine decarboxylase was elevated by approximately 20- and 10-fold at 12 and 60 hours, respectively, after ANIT administration. Putrescine concentration doubled 24-48 hours after the ANIT administration, but spermidine level rose more slowly and reached the level of 1.5-fold of the control level in 36-72 hours. Spermine concentration decreased initially but increased in 96 hours. These results suggest that the increased activity of urea cycle accounts for the increase in the ornithine content and that the putrescine and spermidine acts as the initiator of recovery of the liver damaged by ANIT treatment. 相似文献