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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   
13.
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   
14.
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   
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The seven serotypes (A–G) of botulinum neurotoxin (BoNT) are proteins produced by Clostridium botulinum and have multifunctional abilities: (i) they target cholinergic nerve endings via binding to ecto‐acceptors (ii) they undergo endocytosis/translocation and (iii) their light chains act intraneuronally to block acetylcholine release. The fundamental process of quantal transmitter release occurs by Ca2+‐regulated exocytosis involving sensitive factor attachment protein‐25 (SNAP‐25), syntaxin and synaptobrevin. Proteolytic cleavage by BoNT‐A of nine amino acids from the C‐terminal of SNAP‐25 disables its function, causing prolonged muscle weakness. This unique combination of activities underlies the effectiveness of BoNT‐A haemagglutinin complex in treating human conditions resulting from hyperactivity at peripheral cholinergic nerve endings. In vivo imaging and immunomicroscopy of murine muscles injected with type A toxin revealed that the extended duration of action results from the longevity of its protease, persistence of the cleaved SNAP‐25 and a protracted time course for the remodelling of treated nerve–muscle synapses. In addition, an application in pain management has been indicated by the ability of BoNT to inhibit neuropeptide release from nociceptors, thereby blocking central and peripheral pain sensitization processes. The widespread cellular distribution of SNAP‐25 and the diversity of the toxin's neuronal acceptors are being exploited for other therapeutic applications.  相似文献   
17.
We report satisfactory results with a new operative treatment, conducted via an extensive anterolateral approach, involving 360 degree circumferential capsulotomy, for residual subluxation in congenital dislocation of the hip (CDH). Long-term radiographic results of this procedure (group A) were compared retrospectively with the results of partial capsulotomy (group B), which preserved the posteroinferior joint capsule. The mean center edge angle in group A (22.5°) was greater than that in group B (16.0°). Satisfactory results were achieved in 11 of 15 hips (73%) (Severin class I or II) in group A, and in 5 of 12 hips (42%) in group B. These results suggest that whole circumferential capsulotomy can remove obstacles to complete reduction, and that acetabular development can be expected in hips reduced by the procedure, without the performance of innominate osteotomy. We believe that our technique is a useful alternative for the treatment of residual subluxation in CDH.  相似文献   
18.
Summary In an effort to achieve a simple and less invasive method for the treatment of chronic subdural haematoma, replacement of the haematoma with oxygen by percutaneous subdural tapping was employed in 36 patients. This study was conducted on 23 haematomas in 20 patients, whose computed tomography (CT) scans immediately following the treatment were available for evaluation, with particular regard to distinguishing between their findings and those seen with tension pneumocephalus. The CT features werde divided into two patterns according to the location of oxygen; a convexity type (19 haematomas) and an interhemispheric type (4 haematomas). Analysis of the CT appearances revealed the oxygen was exclusively confined to the haematoma cavity, distinguishing it from the findings in tension pneumocephalus. This observation indicates the safety of replacement of the haematoma with oxygen when combined with our percutaneuous subdural tapping technique which prevents lesions of the inner haematoma membrane.  相似文献   
19.
A rare case of jejunal carcinoma coexisting with adenoma, situated 120 cm distal to the ligament of Treitz in a 53 year old male, is reported herein. We also review cases of adenoma and carcinoma in the jejunum and ileum from the Japanese literature, and discuss the histogenesis of carcinoma of the jejunum and ileum.  相似文献   
20.
 The case of a 49-year-old man with Maffucci’s syndrome, who developed multiple spindle cell hemangioendotheliomas, is presented. The case provides support for recent reports suggesting an association between this peculiar vascular lesion and skeletal enchondromatosis.  相似文献   
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