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61.
The Distally Based Sural Artery Flap for Ankle and Foot Coverage 总被引:1,自引:0,他引:1
Tahseen A. Cheema MD Ehab S. Saleh MD Alex F. De Carvalho MD 《The Journal of foot and ankle surgery》2007,46(1):40-47
The sural artery flap is a distally based fasciocutaneous flap that has many advantages to offer for coverage in the foot and ankle area. It has the largest arc of rotation of all the regional flaps and does not require sacrifice of any major artery, and moderate-to-large-sized defects can be covered adequately. The dissection technique is simple, and donor site morbidity is minimal. We report our experience with 17 cases. Age range was from 13 to 56 years. Ten (59%) defects were posttraumatic, 3 (17%) were related to reconstructive surgery of the foot or tendon Achilles', 2 (11%) resulted from tumor resection, and 1 each were from infection and gunshot wound. The smallest flap was 6 x 4 cm and the largest was 15 x 12 cm, with the average size being 11 x 7.5 cm. In 5 cases, the donor site was closed primarily, and in other cases, split-thickness skin graft was needed. The short saphenous vein was included in the pedicle in all cases. There was no incidence of complete flap necrosis. Follow-up ranged from 3 to 30 months. Two cases (12%) developed partial superficial necrosis. In 1 case, there was partial wound dehiscence that needed debridement and repair. Another case had postoperative discharge, which subsided after removal of the calcaneal plate. None of the patients complained of any functional problem related to loss of sensation along the lateral border of the foot. The sural island flap is a reliable, safe, and easy method of providing soft tissue coverage in the area of the foot and ankle. 相似文献
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Miguel Marcos Alex Soriano José A Martínez Josep Mensa 《Clinical infectious diseases》2007,45(10):1401; author reply 1401-1401; author reply 1402
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Rachel Anderson Lynell Clancy Neil Flynn Alex Kral Ricky Bluthenthal 《The International journal on drug policy》2003,14(5-6):461
An important operational aspect of Syringe Exchange Programmes (SEPs) is the venue of service delivery. This report describes the programmatic features of the Sacramento Area Needle Exchange (SANE), an illegal SEP operating in California, USA. SANE utilises “satellite exchangers” to distribute the bulk of its syringes and HIV risk reduction supplies. Advantages of relying primarily on Designated Exchangers (DE) for delivery of SEP services are that it: (1) allows for coverage of a large geographical area; (2) keeps operational cost low; (3) provides syringes to clients who may not want to or cannot use fixed site programmes; (4) limits the possibility of detection of programme personnel and clients by law enforcement. Limitations are that: (1) it is not as conducive as fixed sites to providing a wide range of ancillary services; (2) it may not be optimal for drug users who do not want to be reliant on other people for access to syringes; (3) those who receive services from a satellite exchanger may not derive as much counselling and referral services as direct exchangers. The lack of legal status, political support and adequate funding threatens the programme’s existence. 相似文献
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Abstract: The main aim of the present investigation was to study systematically the passive and stimulation-evoked release of 3H-5-hydroxytryptamine (3H-5-HT) from rabbit isolated aorta. This was accomplished by preloading rings of aorta with 3H-5-HT (10–6M) and then monitoring by fractional collection the basal 3H-outflow and stimulation-evoked 3H-overflow. The basal 3H-outflow from aorta preloaded with 10–6M of either 3H-5-HT or (-)-3H-noradrenaline (3H-NA) leveled off about 100 min. after the onset of wash-out and remained almost constant thereafter (100–240 min.). The basal 3H-outflow from tissue preloaded with 3H-5-HT was almost 3-fold higher (70–240 min.) than that seen after preloading with 3H-NA. Cocaine (3x10–5M) did not alter the basal 3H-outflow (15–240 min.) from tissue preloaded with 3H-5-HT, while pargyline (5X10–4M) decreased it by about 66% (100–240 min.). Electrical-field stimulation (S1S7, 200 mA, 600 pulses, 0.5 msec, 3 Hz) were applied to the tissue. The initial stimulation-evoked 3H-overflow from aorta preloaded with 3H-5-HT was higher than the subsequent ones (S1-S7: 100, 35, 35, 35, 35, 37, and 40%). Similar results to these were obtained with tissues preloaded with 3H-NA. The stimulation (S1-S7; 200 mA; 600 pulses, 0.5 msec, 3 Hz)-evoked 3H-overflow increased in an apparent linear manner with the amount of current used (50–200 mA). This was also the case for number of pulses (100–900) in the stimulus. The stimulation-evoked 3H-overflow depended in part on the stimulation frequency: unchanged at 2–4 Hz; small increase at 8 Hz; and a 15-fold increase at 16 Hz relative to 2 Hz. Tetrodotoxin (10–6M) decreased the stimulation-evoked 3H-overflow from aorta preloaded with 3H-5-HT (S2-S6) by about 60%, while S1 was not affected. The inhibitory effect of tetrodotoxin was fully reversed by washing the aorta with drug-free salt solution. Omission of Ca2+ from the salt solution reduced the stimulation 3H-overflow by 47–57% (S2-S6) while S1 was unaffected. 6-Hydroxydopamine markedly increased the stimulation-evoked 3H-overflow from 3H-5-HT preloaded rings (180–323% of control). Pargyline (5x10–4M), cocaine (3x10–5M) and removal of endothelium did not alter the stimulation-evoked 3H-overflow evoked by stimulation (S1-S6) of aorta preloaded with 3H-5-HT. It is concluded that 3H-5-HT can be released by electrical-field stimulation as a “false transmitter'’from rabbit isolated aorta. Most of the release is probably of neuronal origin. However, some of the stimulation-evoked 3H-overflow is derived from extraneuronal sites. 相似文献
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Cecilia Johnsson Gunnar Tufveson Lise Binderup Alex Karlsson-Parra 《Xenotransplantation》1997,4(3):186-193
Abstract: The vitamin D analogue MC 1288 (20-epi-1α,25-dihydroxycholecalciferol) effectively postpones rejection of cardiac, intestinal, skin, and aortic allografts. MC 1288 binds to the vitamin D receptor and is thus assumed to exert its immunosuppressive effects via the same mechanisms as 1α,25-dihydroxycholecalciferol, the active form of vitamin D. 1α,25-Dihydroxycholecalciferol has been demonstrated to inhibit the production of various cytokines (interleukin-2, interferon-γ, granulocyte macrophage colony-stimulating factor, and interleukin-12) and to prevent B lymphocyte secretion of immunoglobulins. In the present study MC 1288 was evaluated for its ability to prevent rejection of mouse-to-rat cardiac xenografts, alone and in combination with 15-deoxyspergualin (DSG). Combined treatment with MC 1288 (given days -1 to 9) and DSG (given day -1 and onward) postponed rejection from day 3.0 (untreated recipients) until day 19.5. In rats treated with MC 1288 or DSG as monotherapy, rejection occurred after 3.0 and 7.5 days, respectively. Functioning grafts, obtained on day 9 from recipients treated with MC 1288 and DSG in combination, displayed an almost normal morphology without any obvious deposition of immunoglobulins in the vessels of the grafts and with just a few infiltrating cells. Thus, we have demonstrated synergistic actions of MC 1288 and DSG in delaying rejection of xenografts. Analysis of cellular infiltration, immunoglobulin deposition and graft survival times in the various treatment groups indicate a combined inhibitory effect of these two drugs on the level of macrophage effector function, direct or indirect via T lymphocytes, as well as on antibody production. 相似文献