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21.
This paper describes a technique of fasciocutaneous island flaps used in reconstruction of the lower limb. It is very versatile and some 26 individual flaps in 22 patients have been used to reconstruct skeletal and soft tissue problems from the popliteal fossa to the ankle joint. These longitudinally designed flaps made up of a trilaminate of skin, subcutaneous fat and fascia are aligned within the dermatomal precincts. The most important location for such flap design is along the peroneal compartment sitting within the L5 dermatome and incorporating the superficial peroneal nerve. It can be lengthened as far as the lateral malleolus and is an excellent reconstructive method to close defects over the lower third of the tibia. The medial compartment of the leg employing the saphenous nerve (L4 dermatome) is another area for fasciocutaneous island flap reconstruction, but use is restricted to the upper two-thirds of the tibial area. Posteriorly the island flap design sits along the S2 dermatome, this time incorporating the sural nerve to reconstruct defects of the calf and can be extended to include problems of the popliteal fossa. In the overall flap technique, the age of the patient is not a contraindication and cases with peripheral vascular disease have been treated successfully. The flaps may extend up to a 5:1 ratio in dimension. The operating time can be considerably shortened. 相似文献
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23.
Felix Matthews Valentin Neuhaus Daniel Schmucki Ronald Schwyn Thomas Gross Pietro Regazzoni Otmar Trentz Peter Messmer 《European Journal of Trauma》2005,31(6):568-574
Abstract During treatment of femoral shaft fractures, not only the actual fracture reduction but also the retention of the achieved
reduction is essential. Substantial forces may apply to the bone fragments, due to multidirectional muscular contraction.
Furthermore, forces from manipulation of one bone fragment may be transferred over the soft tissues onto the other fragments,
thus hindering accurate fracture reduction. Once a sufficient reduction has been achieved, this position must be retained
whilst definitive internal fixation is performed. Conventional methods comprise mounting patients on a traction table and
applying manual distraction or employing special distraction devices, such as the AO distractor device. These approaches,
however, only insufficiently stabilize both main fragments. For example, on the traction table the proximal femoral fragment
can pivot around the hip joint thus complicating precise reduction. A novel pneumatic stabilization device to assist surgeons
during operative procedures is described. This passive holding device “Passhold” connects to one main fragment through a minimally
invasive bone interface and statically locks the fragment’s position. Thereafter, only the other main fragment is manipulated
to achieve reduction. Mutual interference of the reciprocal fragment positions, due to soft-tissue force transfer during manipulation,
is avoided. The authors examined the stability of the novel retention device on a test rig and proved its functionality under
sterile settings using cadaver tests. It is concluded that this device largely facilitates the operative procedure in femoral
shaft fractures, is sufficiently stable and ergonomically suitable for intraoperative deployment. 相似文献
24.
25.
Acute radiation reactions in oral and pharyngeal mucosa: tolerable levels in altered fractionation schedules. 总被引:3,自引:0,他引:3
Jack F Fowler Paul M Harari Felix Leborgne José H Leborgne 《Radiotherapy and oncology》2003,69(2):161-168
PURPOSE:To investigate whether a predictive estimate can be obtained for a 'tolerance level' of acute oral and pharyngeal mucosal reactions in patients receiving head and neck radiotherapy, using an objective set of dose and time data. MATERIALS AND METHODS:Several dozen radiotherapy schedules for treating head and neck cancer have been reviewed, together with published estimates of whether they were tolerated or (in a number of schedules) not. Those closest to the borderline were given detailed analysis. Total doses and biologically effective doses (BED or ERD) were calculated for a range of starting times of cellular repopulation and rates of daily proliferation. Starting times of proliferation from 5 to 10 days and daily cellular doubling rates of 1-3 days were considered. The standard published form of BED with its linear overall time factor was used: BED=nd(1 + d/(alpha/beta) - Ln2(T - T(k))/alpha T(p) (see text for parameters). RESULTS: A clear progression from acceptable to intolerable mucosal reactions was found, which correlated with total biologically effective dose (BED in our published modeling), for all the head and neck cancer radiotherapy schedules available for study, when ranked into categories of 'intolerable' or 'tolerable'. A review of published mechanisms for mucosal reactions suggested that practical schedules used for treatment caused stimulated compensatory proliferation to start at about 7 days. The starting time of compensatory proliferation had little predictive value in our listing, so we chose the starting time of 7 days. Very short and very long daily doubling rates also had little reliability, so we suggest choosing a doubling time of 2.5 days as a datum. With these parameters a 'tolerance zone of uncertainty' could be identified which predicted acute-reaction acceptability or not of a schedule within a range of about 2-10 Gy in total BED. If concurrent chemoradiotherapy is used, our provisional suggestion is that this zone should be reduced by up to roughly 3-5 Gy10 in BED, with a request for further evidence. CONCLUSIONS:It is suggested that total BED should be used, as specified above. Parameters of alpha=0.35 Gy-(1), alpha/beta=10 Gy, Tk=7 days and Tp=2.5 days are suggested. The 'acute/ tolerance zone' then turns out to be 59-61 Gy10 for radiation-only treatments. Further information about the decrement caused by concurrent head-and-neck cancer chemoradiotherapy, possibly 3-5 Gy10, is required. 相似文献
26.
27.
Superior mesenteric artery is more important than inferior mesenteric artery in maintaining colonic mucosal perfusion and integrity in rats 总被引:1,自引:0,他引:1
Dr. Felix W. Leung MD Kenny C. Su MD Jose M. Pique MD Gerard Thiefin MD Edward Passaro Jr MD Paul H. Guth MD 《Digestive diseases and sciences》1992,37(9):1329-1335
Mucosal hemodynamics (by reflectance spectrophotometry) and mucosal damage (by histologic examination) following acute colonic ischemia were evaluated in different anatomic locations in the colon of anesthetized rats. The reflectance spectrophotometer provides an index of mucosal hemoglobin concentration (IHB) and an index of oxygen saturation of hemoglobin (ISO2). The patterns of ischemia without congestion (IHB, ISO2) during superior mesenteric artery occlusion, and ischemia with congestion (IHB, ISO2) during portal vein occlusion, previously demonstrated in the stomach and duodenum, are also applicable to the colon. The significant linear correlations between changes (as percent of baseline) in IHB, ISO2, and hydrogen gas clearance suggest that changes in these indices are adequate indicators of changes in colonic mucosal perfusion. Superior mesenteric artery ligation produced significant reductions in both indices, and an increase in damage in the mucosa of the cecum, transverse colon, splenic flexure, and left colon, but not the rectum. Inferior mesenteric artery ligation produced only slight reduction in these indices and minimal damage only in the mucosa of the splenic flexure. These results support the hypothesis that the superior mesenteric artery is more important than the inferior mesenteric artery in maintaining colonic perfusion and colonic mucosal integrity in the rat.Supported by the American Society for Gastrointestinal Endoscopy Career Development Award (H850208, H870212), Veterans Administration Medical Research Funds; and in part by research grants (0162-01, 0162-02; 0291-01) from the Smokeless Tobacco Research Council, Inc.; and by funds provided by the Cigarette and Tobacco Surtax Fund of the State of California through the Tobacco Related Disease Research Program of the University of California. 相似文献
28.
29.
Nikos Pandis Sverre Heim Georgia Bardi Ingrid Idvall Nils Mandahl Felix Mitelman 《Genes, chromosomes & cancer》1993,6(1):51-57
Short-term cultures from 20 breast carcinomas were analyzed cytogenetically. A normal female chromosome complement was found in 4 cases. Clonal chromosome aberrations were detected in 16 tumors. In 10 tumors, multiple cytogenetic clones were found; in 2 cancers the clones were related, reflecting clonal evolution, but in the remaining 8 tumors the clones were cytogenetically unrelated, indicating clonal heterogeneity in the origin of the tumor parenchyma. Correlation analysis between karyotypic and pathologic parameters indicated that cases with complex karyotypes and/or cytogenetically unrelated clones, when compared with cases with a single simple karyotypic abnormality, were generally of higher histologic malignancy grade, had more mitoses in the histologic sections, and also more often had carcinoma in situ lesions in the same breast. © 1993 Wiley-Liss, Inc. 相似文献
30.
Frequent rearrangement of chromosomal bands 1p22 and 11q13 in squamous cell carcinomas of the head and neck 总被引:1,自引:0,他引:1
Yuesheng Jin Koichiro Higashi Nils Mandahl Sverre Heim Johan Wennerberg Anders Birklund Michael Dictor Felix Mitelman 《Genes, chromosomes & cancer》1990,2(3):198-204
We report the finding of clonal structural chromosome abnormalities in short-term cultures from 15 squamous cell carcinomas of the head and neck region. When the distribution of chromosomal breakpoints in these 15 tumors and in the 16 head and neck carcinomas previously described are assessed, a marked clustering is seen at bands 1p22 and 11q13, which are rearranged in eight and nine tumors, respectively. No other band was involved in aberrations in more than five tumors. Cytogenetic evidence of gene amplification was seen in four tumors, three times in the form of homogeneously staining regions (twice located in 11q13), and in one tumor as double minutes. Among the candidate genes for such amplification are BCLI, INT2, and HSTI, all of which map to 11q13, and NRAS, which maps to 1p22. All these oncogenes have previously been shown to be amplified in subsets of head and neck carcinomas. We conclude that bands 1p22 and 11q13 are nonrandomly involved in chromosomal rearrangements in head and neck carcinomas and suggest that activation of oncogenes located in these bands may proceed via cytogenetic mechanisms. 相似文献