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41.
Intraosseous ganglia of the glenoid are rare, and their etiology is unknown. This report describes a case of an intraosseous ganglion about to cause fracture of the glenoid. The patient was a 61-year-old woman with a painful left shoulder with a limited range of motion. Her symptoms did not improve after non-operative treatment. Arthroscopic examination showed a cartilage defect and erosion in the posteroinferior portion of the glenoid, behind which computed tomography (CT) showed a cystic lesion of the glenoid. There was no communication between the cyst and the joint space. The patient was treated by curettage and an autogenous cancellous bone graft from the iliac crest. Two years after the operation, the patient was almost free from pain, and CT showed good integration of the bone graft.  相似文献   
42.
The presenting symptoms of Wilson disease and its natural history as related to age are described based on 283 cases collected in Japan. The disease presented with a variety of signs and symptoms; the most frequent were in order of frequency jaundice, dysarthria, clumsiness, tremor, drooling, gait disturbance, malaise and arthralgia. The mean age at onset of the disease was 12.0 years. Hepatic and osteoarthral symptoms developed early and neurological symptoms late. Fifty-eight cases develolped neurological symptoms only, 28 cases had hepatic symptoms only, and in 26 cases hepatic mortality rate was observed in hepatic, hepato-haematological and hepato-renal cases mainly due to acute hepatic failure resulting in death only a few weeks after onset. Cases having only neurological symptoms showed a more favourable prognosis with a longer survival.  相似文献   
43.
MRI in subacute combined degeneration   总被引:13,自引:0,他引:13  
We describe a patient with clear lesions in the spinal cord on MRI due to subacute combined degeneration. T2-weighted images clearly showed abnormal high signals in the posterior columns, which disappeared on recovery from the disease.  相似文献   
44.
This study was carried out to evaluate the effects of low-level laser irradiation on experimental lesions of articular cartilage. A standard lesion was practised on the femoral trochlea of both hindlimbs of 20 clinically normal Californian rabbits. These animals were divided into two groups of 10 individuals each, depending on the laser equipment used for treatment. Onc group was treated with He-Ne laser (8 J cm-2, 632.8 nm wavelength) and the other with infra-red (IR) laser (8 J cm-2, 904 nm wavelength). In both groups, five points of irradiation to the right limb alone were irradiated per session for a total of 13 sessions, applied with an interval of 24 h between sessions. These points were the following: left and right femoral epicondyles, left and right tibial condyles and the centre of articulation. The distance between these points was approximately 1 cm. The untreated left limb was left as a control. During treatment, extension angle and periarticular thickness were considered. At the end of the treatment, samples were collected for histopathologi-cal study and stained with: Haematoxylin-Eosin, PAS and Done. The results show a statistically higher anti-inflammatory capacity of the IR laser (p < 0.0001). The functional recovery was statistically similar for both treatments (p < 0.176). Histological study showed, at the end of the treatment, hyaline cartilage in the IR group, fibrocartilage in the He-Ne group and granulation tissue in the control limbs. Clinical and histological results indicated that this laser treatment had a clear anti-inflammatory effect that provided a fast recuperation and regeneration of the articular cartilage.  相似文献   
45.
The articular cartilages from the left knee of 30 rabbits immobilized in casts in functional position were studied under transmission electron microscope. The pathological changes which begin at early stage of immobilization included both degeneration and repair of cartilage. The striking morphological features observed were: (1) most chondrocytes in various layers of cartilage underwent progresive degeneration; (2) the concomitant abnormal proliferation of some chondrocytes happened in a brief period. The changes in mechanical stress caused by immobilization affected the nutrition of cartilage and finally led to its reactive structural reformation.  相似文献   
46.
Formation of intrachondral vessels (cartilage canals) in the proximal femoral epiphysis was studied in 13- to 22-week-old human fetuses using a corrosion casting technique and scanning electron microscopy. Several successive morphological stages of angiogenesis occurring inside the hyaline cartilage were distinguished. The process of cartilage vascularization starts with the formation of hairpin loops sent off from the perichondrial vascular network into the adjacent cartilage. A capillary glomerulus is then formed at the leading end, and the entire vascular unit grows in length, assuming a mushroom-like shape. Its further elongation is accompanied by a backward expansion of the capillary network which surrounds a pair of main vessels (arteriole and venule) like a manchette. The subsequent branching of such primary vascular units proceeds according to the same morphological patterns. The resulting tree-like vascular formations become interconnected via their lateral branches. This study clearly supports the invasion theory of cartilage canal formation.  相似文献   
47.
An electron microscopic study was done on abductor pollicis brevis muscles of 18 Rhesus monkeys after intramuscular injections of 0.75% bupivacaine, 2% mepivacaine, or 2% lidocaine + epinephrine. The muscles were examined for from 2 h to 28 days. Severe muscle fiber damage, consisting of breakdown of sarcolemma and myofibrils, was seen as early as 2 h. Phagocyte mediated fragmentation of the degenerating muscle fibers was at its peak during the third and fourth days. Myoblasts were abundant during the fourth day. Early myotubes appeared on the fifth and sixth days, and they matured during the second week. Satellite cells appeared alongside mature myotubes. Overall, the local anesthetic-induced breakdown and regeneration of skeletal muscle fibers in the monkey followed a course quite similar to that seen in the rat.  相似文献   
48.
In this study, large areas of goldfish telencephalon were ablated including rostral nucleus preopticus periventriculare (rNPP), and degenerating axons were traced by a modified Fink and Heimer procedure. The lesioning procedure ablated large regions of area dorsalis telencephali pars medialis, centralis, and dorsolateral complex; and completely removed area ventralis telencephali pars dorsalis, ventralis, and lateralis. In addition, the supracommissural nucleus and rNPP were lesioned specifically because both nuclei have been thought to be involved in courtship behavior and endocrine control of reproduction. This investigation demonstrated extensive fiber projections from telencephalic nuclei and/or rNPP to the hypothalamus. Lesioned telencephalon and/or rNPP projected bilaterally to nucleus preopticus and the suprachiasmatic nucleus and unilaterally to the following tuberal nuclei: nucleus anterior tuberis, and the lateral hypothalamic nucleus. A much larger fiber projection to the inferior lobe nuclei was also observed with a large contralateral as well as ipsilateral input.  相似文献   
49.
We tested the hypothesis that electric perturbation influences 45Ca incorporation in extracellular matrix (ECM) of cartilage in vitro. Hypertrophic chondroblasts of tibial epiphyses (HC), sternum (SC), and skin fibroblasts (F) were cultured from chick embryos. HC, SC, and F cells were micromass seeded three times per week and maintained at 37.5 degrees C with 5% CO2 for two weeks. Cultures were randomly designated control (C) or exposed (E) to a pulsed electromagnetic field (PEMF). A time course experiment of calcium incorporation for all cultured groups showed that 24 h of exposure produced the largest biological response in chondroblasts. Calcium incorporation required supplemental phosphate. Autoradiography data indicated that the calcium incorporation into macromolecules largely occurred in the ECM. 45Ca steady-state perturbation was enhanced by Streptomyces hyaluronidase (SH) but not by testicular hyaluronidase (TH). 45Ca incorporation experiments tested the effects of phosphate, SH, TH, and PEMF alone and in various combinations on these cultures. Only PEMF or SH plus PEMF with phosphate enhanced 45Ca incorporation. Other experiments examined the effect of rotenone or freeze-thawing on cells exposed to PEMF. PEMF plus freeze-thaw enhanced calcium incorporation in HC only. PEMF appeared to cause disruption of the ECM, enhancing the probability of matrix calcification.  相似文献   
50.
Cricket fast bowlers are the potent strike force in a multidiscipline team. They subject their spines to repetitive sagittal plane and rotatory movements over many years. The effect of this repetitive stress has not previously been analysed. This study examined 20 former fast bowlers to determine the incidence of spondylolysis, spondylolisthesis and degenerative change. Fast bowlers are noted to have an increased incidence of spondylolysis. A mixed front/side bowling style involving more lumbar hyperextension or rotation has significant association with spondylolysis when compared with side-on bowling styles. There was a high incidence of radiological thoracolumbar degenerative facet joint and disc disease in former fast bowlers.  相似文献   
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