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71.
PURPOSE: Many patients attend orthopedic departments complaining of pain on the plantar aspect of the calcaneum. The symptoms may subside spontaneously, but often persist. Treatment is usually by local injection of a corticosteroid, orthopedic devices or other standard treatment. If these methods fail, X-ray treatment may be considered. The efficacy of radiotherapy of the calcaneal spur was evaluated. PATIENTS AND METHODS: From April 1981 through December 1991, 18 patients with painful heel were irradiated mostly with the caesium or telecobalt unit, usually with a dose of 4 times 0.5 Gy. Among these patients, 12 could be followed up during a prolonged period on the basis of questionnaires. RESULTS: According to the categories of v. Pannewitz 17% of the patients were pain-free by the end of the treatment course, 22% showed marked improvement, 33% showed improvement and in 28% the pain was not influenced. Over an average of 41.5 months 58% of the patients reported freedom from pain. CONCLUSIONS: Low-dose radiotherapy appears to relieve the painful heel syndrome in a high proportion of patients. The overall treatment risk appears to be very small. The mechanism of low-dose radiotherapy is unknown. 相似文献
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The mechanisms responsible for long-lasting, activity-dependent decreases in synaptic efficacy are not well understood. We have examined the initial steps required for the induction of long-term depression (LTD) in CA1 pyramidal cells by repetitive low frequency (1 Hz) synaptic stimulation. This form of LTD was synapse specific, was saturable, and required activation of post-synaptic NMDA receptors. Loading CA1 cells with the Ca2+ chelator BAPTA prevented LTD, whereas lowering extracellular Ca2+ resulted in the induction of LTD by stimulation that previously elicited long-term potentiation. Following LTD, synaptic strength could be increased to its original maximal level, indicating that LTD is reversible and not due to deterioration of individual synapses. Induction of homosynaptic LTD therefore requires an NMDA receptor-dependent change in postsynaptic Ca2+ which may be distinct from that required for long-term potentiation. 相似文献
73.
In order to investigate the blood supply of osteo-periosteal flap of lateral inferior part of tibia, 40 lower limbs of adult cadavers were observed. The result showed that the superior malleolar branch was the biggest branch on the lateral inferior part of tibia and served as the main blood supply to the above area. It originated from the anterior tibial artery, 3.1 +/- 0.8 cm above the intermalleolar line. During its way to the anterior border of the tibia, it gave out the ascending and descending branches. The ascending branch was along the anterior border upward and anastomosed with the musculo-periosteol branch of the anterior tibial artery at the level of 6.3 +/- 1.3 cm above the intermalleolar line. The decending branch was anastomosed with the anterior medial malleolar artery. For the anastomosis between the superior malleolar branch with the peripheral vessels, the osteo-periosteol flap could be designed at the lateral side of the lower part of tibia in size of 8-10 cm x 4-6 cm. This was a new donor area of osteo-periosteol flap for repair of non-union of bone in lower end of tibia or arthrodesis of the ankle joint. 相似文献
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OBJECTIVE: Functional written communication, an important goal in the rehabilitation of persons with tetraplegia, frequently is met through the use of personal computers and alternative computer access systems. To make informed decisions about alternative access systems, the therapist needs information on the efficacy of the available choices. The purpose of this study was to investigate the effectiveness of two commercially available systems for text entry, the traditional mouthstick and the Prentke Romich HeadMaster. METHOD: Participants were a 25-year-old man and 76-year-old woman who both functioned at a C5 neurological level. Neither participant had previous experience with either system for text entry. A single-subject research design was used whereby Participant 1 experienced six phases of treatment (i.e., CBCBCB, where C = mouthstick and B = HeadMaster), and Participant 2 experienced four phases of treatment (i.e., BCBC). RESULTS: Participant 1 achieved a maximum rate of text entry of 5.85 wpm with both the HeadMaster and the mouthstick, whereas Participant 2 achieved a maximum rate of 7.15 wpm with the mouthstick and 4.85 wpm with the HeadMaster. Results from this study were similar to the results from previous comparison studies of persons with severe disabilities who had no experience with alternative computer access systems. CONCLUSION: Both participants were able to use both systems successfully; however, their respective rates of text entry were too slow to be functional in most employment situations. 相似文献
77.
CP Tensen KJ Cox JF Burke R Leurs RC van der Schors WP Geraerts E Vreugdenhil H Heerikhuizen 《Canadian Metallurgical Quarterly》1998,10(11):3409-3416
Neuropeptide Y is an abundant and physiologically important peptide in vertebrates having effects on food intake, sexual behaviour, blood pressure and circadian rhythms. Neuropeptide Y homologues have been found in invertebrates, where they are very likely to play similar, important roles. Although five neuropeptide Y-receptor subtypes have been identified in mammals, none has been reported from invertebrates. Here we describe the cloning of a neuropeptide Y-receptor from the brain of the snail Lymnaea stagnalis. The identity of the receptor was deduced by expressing the neuropeptide Y-receptor-encoding cDNA in Chinese Hamster Ovary cells, which were subsequently challenged with size-fractionated Lymnaea brain extracts. An active peptide, selected on the basis of its ability to induce changes in cAMP levels, was purified to homogeneity, analysed by mass spectrometry and amino acid sequence determination, and turned out to be a Lymnaea homologue of neuropeptide Y. 相似文献
78.
BACKGROUND: Surgical defects of the central upper lip (philtrum) are a particularly difficult area to achieve satisfactory cosmetic and functional repair. Reconstruction of the central upper lip has been accomplished primarily through the use of side-to-side closure, bilateral advancement or rotation flap, and full-thickness graft. Repair may be complicated by distortion of the vermilion border, obliteration of the normal contour of the philtrum, eclabium, and trapdooring of the flap. OBJECTIVE: We review the options for reconstruction of this area and describe our experience using an island pedicle flap to complete reconstruction. METHODS: Four patients presented with basal cell carcinomas of the mid upper lip (philtrum). Tumors were cleared by Mohs micrographic surgery. Reconstruction was achieved by island pedicle flaps utilizing donor tissue from the superior philtrum. RESULTS: The patients had excellent cosmetic results with minimal distortion of the vermilion border or obliteration of the philtrum or philtral ridges. Scars healed in a nearly imperceptible fashion, keeping within one cosmetic unit (the philtrum) without extending along the vermilion border as seen in bilateral advancement or rotation flaps. CONCLUSIONS: Island pedicle flaps may be an effective cosmetic and functional repair of selected surgical defects of the central upper lip involving the philtrum. 相似文献
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CG Salomon CL Kalbhen CM Dudiak MC Olson ME Flisak RC Flanigan 《Canadian Metallurgical Quarterly》1998,206(2):533-538
The effects of denervation of central noradrenergic system on the interpartner relationships of adult cats were examined in a predatory test in the competitive situation for paired animals. Direct administration of the noradrenaline neurotoxin, N-2-chloroethyl-N-ethyl-2-bromobenzylamine (DSP-4 12 microg) into the medial forebrain bundle (MFB) of submissive cats changed previously established dominant-submissive relationship. Biochemical analysis demonstrated a significant reduction of noradrenaline (NA) concentration in the hypothalamus (AH), amygdala (AM), hippocampus (HC), and frontal cortex (CTX), and elevation of NA content in the midbrain central gray matter (CG) in MFB-lesioned cats. Simultaneously, DSP-4-induced lesions exerted significant decrease of 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) content in AH, CG, HC and CTX, and increased GABA level in AH, CG, AM, and HC. These results suggest that a coincident decrease of NA metabolism and increase of GABA metabolism led to fear drive reduction. 相似文献