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1.
Nicholas L. Shortt Gary F. Keenan Andrew Y. Muir Prof. Dr. A. Hamish R. W. Simpson 《Operative Orthopadie und Traumatologie》2006,18(4):364-376
OBJECTIVE: Avoidance of potential iatrogenic nerve injury during insertion of Ilizarov fine wires into areas of high anatomic risk by using a modified nerve stimulation technique. INDICATIONS: Application of the Ilizarov ring fixator to areas of high anatomic hazard, in situations where anatomic topography may be distorted by previous surgery, trauma, or congenital anomalies. CONTRAINDICATIONS: Use of systemic muscle relaxants. Caution in patient with cardiac pacemaker. SURGICAL TECHNIQUE: Preliminary experiments showed that a standard nerve-stimulating device can deliver a negatively charged, monophasic square pulse of current through Ilizarov wires. During the application of an Ilizarov frame to potentially hazardous anatomic regions, providing no systemic muscle relaxants are used, a voltage field sufficient to cause nerves in close proximity to the Ilizarov wire to depolarize is produced. Identification of a distal muscle twitch provoked by the stimulation may indicate a potential for iatrogenic nerve injury. RESULTS: Results show that with the nerve stimulator set at 2.5 mA (pulsed at a frequency of 2 Hz), peripheral nerves are stimulated if they lie within 5 mm of the wires. Should a distal muscle twitch occur, wires should be repositioned so that equivalent stimulation produces no twitch. The technique was used during Ilizarov frame application in ten patients, with only a single occurrence of distal muscle twitches in a lower-leg frame. Following repositioning of the Ilizarov wire in this case, no further twitches were observed, indicating that no Ilizarov wire was inserted close to peripheral nerves. No neurologic impairment was present postoperatively. 相似文献
2.
S. A. R. Nouraei C. B. Singh M. S. Ferguson K. Young D. Roy J. M. Philpott 《European journal of plastic surgery》2007,30(4):153-157
The objective of this study is to assess the results of repairing septal perforations with a vascularized pedicled alar cartilage
island flap. Using the external rhinoplasty approach, a vascularized flap of alar cartilage, harvested as a cephalic trim
and pedicled on the ascending columellar branches of the superior labial artery was raised. Bilateral mucoperichondrial septal
flaps were elevated and the alar flap was transposed and secured within the defect and bilaterally overlaid with temporalis
fascia. Silastic sheets were placed and remained in situ until the grafts were revascularized from the peripheries of the
defect as well as centrally from the alar flap. The revascularized temporalis fascia acted as a scaffold for nasal remucosalization.
The alar flap also increased the long-term structural robustness of the repair. Between 1999 and 2003, 14 patients with septal
perforations ranging from 10 to 31 mm underwent septal reconstruction using this technique. There were nine males and five
females. The flap was successfully raised in all cases and long-term closure was maintained in 12 patients (86%). The alar
cartilage flap is an effective technique for repairing septal perforations in selected patients. It provides vascularized
tissue which nourishes the grafts during remucosalization, and a cartilaginous framework, which affords long-term structural
support to the repair. It also obviates the need to transpose nasal mucosa and create a secondary defect. The rhinoplasty
approach furthermore permits additional nasal deformities to be corrected at the same time.
Presented at the British Association of Plastic Surgeons Summer Scientific Meeting, Sheffield, UK (12 July 2006). 相似文献
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The introduction of laparoscopic inguinal hernia repair (LIHR) has been controversial. A questionnaire was sent to all general surgeons in New Zealand to document the early experience with LIHR and attitudes towards it. Of the 118 replies (response rate 55%). 74 were from laparoscopic surgeons. 26 of whom had performed 564 (201 public. 363 private) LIHR (23 bilateral) until January 1994. Only nine (35%) of these surgeons had assisted an experienced surgeon before performing an LIHR. and only four (15%) were supervised by an experienced surgeon during their first case. The transabdominal preperitoneal technique of LIHR was used by 14 (54%) surgeons. the extraperitoneal technique by eight (31%), and the tronsabdominal onlny technique by four (15%). There were 29 (5%) recurrences, 17 (3%) neuropathies. seven (1.2%) conversions, four (0.7%) miijor perforations. and one (0.17%) death. Of the 26 surgeons who performed LIHR, 20 (77%) were concerned about the absence of long-term results. 14 (54%) considered that the optimal technique had not been established. 13 (50%) were concerned about the unique complications associated with LIHR. 11 (42%) were less enthusiastic about performing LIHR than previously. 10 (38%) were doubtful about its advantages, and six (23%,) were uncertain about its future and considered that it should only be performed within the context of a controlled trial. This study highlights a number of issues that need to be addressed before the role of LIHR can be determined. 相似文献
7.
Marcy E. MacDonald Hamish S. Scott William L. Whaley Thomas Pohl John J. Wasmuth Hans Lehrach C. Phillip Morris Anne-Marie Frischauf John J. Hopwood James F. Gusella 《Somatic Cell and Molecular Genetics》1991,17(4):421-425
-l-Iduronidase (IDUA) has been intensively studied due to its causative role in mucopolysaccharidosis type I (Hurler, Scheie and Hurler/Scheie syndromes). The recent cloning of a human IDUA cDNA has resulted in a reevaluation of the chromosomal location of this gene. Previously assigned to chromosome 22, IDUA now has been localized to 4p16.3, the region of chromosome 4 associated with Huntington's disease (HD). The existence of a battery of cloned DNA, physical map information, and genetic polymorphism data for this region has allowed the rapid fine mapping of IDUA within the terminal cytogenetic band of 4p. IDUA was found to be coincident with D4S111, an anonymous locus displaying a highly informative multiallele DNA polymorphism. This map location, 1.1×106 bp from the telomere, makes IDUA the most distal cloned gene assigned to 4p. However, it falls within a segment of 4p16.3 that has been eliminated from the HD candidate region, excluding a role for IDUA in this disorder. 相似文献
8.
Janine Jason Lennox K. Archibald Okey C. Nwanyanwu Anne L. Sowell Ian Buchanan Joshua Larned Michael Bell Peter N. Kazembe Hamish Dobbie William R. Jarvis 《Clinical and Vaccine Immunology : CVI》2002,9(3):616-621
In animal studies, vitamin A deficiency induces a shift from type 2 (humoral) to type 1 (cellular) cytokines; there are no similar data for humans. Control of human immunodeficiency virus (HIV) and Mycobacterium tuberculosis infections requires type 1 cytokine (cellular) immunity. These infections and vitamin A deficiency are highly prevalent in Africa. We therefore examined the interactions among serum vitamin A levels, immune parameters, HIV infection status, Mycobacterium bovis BCG vaccine scarring (as an indicator of a type 1 cytokine profile), and clinical findings for 70 hospitalized children in Malawi, Africa. Directly conjugated monoclonal antibodies and flow cytometry were used to assess cell-specific cytokine production by peripheral blood monocytes and lymphocyte subpopulations. The statistical techniques employed included nonparametric statistics and logistic regression analyses. Thirty percent of the participants had severe vitamin A deficiency (<10 μg/dl), 34% had moderate deficiency (10 to <20 μg/dl), and 36% had normal levels (≥20 μg/dl). Vitamin A levels were lower for HIV-positive than for HIV-negative children (median, 10 and 17 μg/dl, respectively). Vitamin A-deficient children (<20 μg/dl) were more likely than non-vitamin A-deficient children to have higher proportions of natural killer (NK) cells (median, 8.3 and 5.2%, respectively) and lower ratios of interleukin-10-producing monocytes to tumor necrosis factor alpha-producing monocytes after induction (median, 1.0 and 2.3, respectively). Vitamin A-deficient children were also more likely than non-vitamin A-deficient children to exhibit respiratory symptoms (47% versus 12%) and visible BCG vaccine scars (83% versus 48%), which are indicative of a type 1 response to vaccination. Vitamin A status did not vary with gender, age, incidence of malaria parasitemia, blood culture positivity, or rates of mortality (6% of vitamin A-deficient children died versus 20% of non-vitamin A-deficient children). Lower vitamin A levels were associated with a relative type 1 cytokine dominance and proportionately more NK cells, both of which may be somewhat beneficial to persons who are exposed to HIV, M. tuberculosis, or other type 1 pathogens. 相似文献
9.
MacDougall HG Brizuela AE Curthoys IS 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,148(2):166-175
Recent studies have shown that, although responses to long-duration, constant-current surface galvanic vestibular stimulation
(GVS) show substantial interindividual variability, individual subjects show a reliable, repeatable, idiosyncratic oculomotor
response pattern to GVS. It follows that GVS may be a more reliable stimulus than may have been anticipated from the literature.
The aim of the present study was to examine the metrics of 3D eye-movement responses to maintained (120 s), unilateral and
bilateral surface GVS. Eye movements were measured using computerised video-oculography. Two experiments were conducted: Experiment
1 examined whether the normal response is linear over increasing levels of current; and Experiment 2 examined (1) whether
the normal response to surface GVS is symmetrical when comparing stimulated sides, (2) whether the normal response to surface
GVS is symmetrical when the polarity of the stimulating current was reversed, and (3) whether there is additivity in the normal
response to combinations of unilateral/bilateral surface GVS. Five subjects participated in Experiment 1 and eight subjects
participated in Experiment 2. In both experiments, the onset of stimulation produced characteristic eye-movement responses:
changes in torsional position with the upper pole of both eyes rolling towards the anode and away from the cathode; together
with horizontal and torsional nystagmus with slow phases towards the anode and away from the cathode; and negligible vertical
nystagmus. These responses reversed direction at stimulus offset. In the fixation condition of Experiment 1, the magnitude
of ocular torsional position (OTP) and torsional nystagmus responses showed a linear relationship over conditions of increasing
current strength, as did OTP, torsional and horizontal nystagmus responses in darkness. The results of Experiment 2 showed
that responses to unilateral stimulation are symmetrical between stimulated sides, symmetrical between stimulating polarities,
and additive (with respect to responses to bilateral stimulation). The principles derived from these findings, as well as
those of recent studies, provide a foundation for future work investigating eye-movement responses to surface GVS in patients
with known types of vestibular dysfunction.
Electronic Publication 相似文献
10.
Recovery from oxygen poisoning in Drosophila 总被引:1,自引:0,他引:1