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This study investigates whether tissue recoil or patient intrinsic factors influence the final position of the nipple areola complex (NAC) after reduction mammoplasty. The age, pre-operative ptosis, BMI and weight of the tissue resected were recorded as patient intrinsic factors in 37 patients undergoing reduction mammoplasty. The “spring-back” value was defined as the distance from the sternal notch to a nipple landmark on the breast meridian with the patient sitting up, minus the same measurement repeated with the patient recumbent to eliminate the pull of gravity on the breast. Spring back was measured pre-operatively for the nipple and nipple mark then post-operative for the nipple. The difference in centimeters between the final post-operative distance from the sternal notch to the nipple and the level intended by the pre-operative nipple mark was termed the “judgment error.” The final position of the post-operative nipple and the judgment error was compared to the spring-back values and patient intrinsic factors. Pre-operative ptosis was statistically related to increasing patient BMI and mass of tissue resected per breast. Pre-operative spring-back values for the nipple increased with increasing ptosis, BMI and decreasing age. Spring-back values were greater in the lower pole of the breast than in the upper pole. The final position of the nipple was higher than the pre-operative mark in 65% of cases, lower in 8% and as marked in 27% of cases. The post-operative NAC was, on average, 0.6 cm higher than planned pre-operatively. The post-operative distance from the sternal notch to the nipple increased with increasing pre-operative ptosis, mass of breast tissue resected per breast and all three spring-back values. The difference between the level of the pre-operative mark and the final nipple position showed a weak correlation with post-operative spring-back values. The parameters of ptosis, BMI, weight of tissue resected per breast and pre-operative nipple spring back reflect body habitus and breast size. Spring-back values vary between the upper and lower pole of the breast. The final NAC position was higher than that intended at pre-operative marking in the majority of cases. The surgeon instinctively marks the nipple lower in patients with greater pre-operative ptosis and in whom a larger resection is anticipated. Judgment error did not relate to intrinsic factors nor to pre-operative spring-back values; hence, these parameters cannot be applied as predictive tools for more accurate pre-operative marking of the nipple position. This study suggests that the pre-operative nipple mark should be placed, with the patient sitting up, at least 23 cm from the sternal notch and 0.6 cm lower than the final position estimated using the inframammary crease as a landmark. An invited commentary on this paper is available at .  相似文献   
3.
目的 分析空气灌肠治疗小儿肠套叠的各种影响因素。方法 对117例确诊肠套叠的患儿,采用双腔气囊外接压力计或不接压力计,在X线透视下行空气灌肠。结果 117例中,完全复位92例(78%),复位失败17例(14.5%),不完全复位8例(6%)。结论 空气灌肠是治疗小儿肠套叠的重要方法,其影响复位成功与否的因素,主要有套入时间、类型、复位方法等。  相似文献   
4.
目的:总结32例经椎弓根椎间融合与AF治疗胸腰椎骨折的经验。方法:应用经伤椎椎弓根椎体间融合并AF系统复位内固定,以提高复位效果与脊柱的稳定性。结果:全部病例获随访,时间3~23个月,伤椎均与上位椎体间融合,无矫正角度与高度丢失,无断钉及螺钉松动,神经功能平均1.5级以上的恢复。结论:经椎弓根椎间融合与AF治疗胸腰椎骨折,操作简单,复位可靠,可重建脊柱的稳定性,椎体间融合更符合生物力学内环境的持久稳定。  相似文献   
5.
沈氏经椎弓根内固定装置治疗胸腰段脊柱脊髓损伤   总被引:25,自引:1,他引:24  
本组使用沈氏经椎弓根内固定装置共治疗胸腰段脊柱损伤104例。其中男82例,女22例。年龄16~68岁,平均38岁。伴有脊髓神经损伤73例(70.2%)。随访时间6~54个月,平均26个月。治疗结果,后凸畸形角由术前27.6°矫正到术后4.4°,矢状面水平位移由术前31.2%纠正到术后0%,压缩椎体高度由术前的52.9%恢复到术后的96.4%。椎管矢状径和面积分别由术前的11mm和1.2cm2恢复到术后的14.4mm和1.8cm2(P<0.05)。不完全截瘫组术后神经功能有Frankel一级以上改善的为90.6%。临床疗效表明沈氏装置是胸腰段脊柱损伤可选择的良好内固定之一。  相似文献   
6.
The management of patients through the use of evidence-based medicine has become the 'mantra' of medicine within many Western countries. Evidence-based medicine is aimed at providing the best objective, scientific care to all patients, and reducing as far as possible patients' risks of disease and complications from disease. Based on family physicians' discussions of the use of evidence-based recommendations for two cardiac diseases, this paper explores how subjectively-based trust enters into family physicians' decision to use evidence-based medicine. In addition, we show how trust influences physicians' work of recommending evidence-based medicine to patients, and physicians' perceptions of why patients follow recommendations aimed at risk reduction. We conclude that although much of the current discussion about evidence-based medicine assumes a 'rational' model of physician behaviour based on the application of the 'best objective scientific' results, subjectively-based perceptions of trust influence physician practices, and point to the need to understand the power of relational issues in influencing physician practices even when utilizing evidence-based knowledge.  相似文献   
7.
Reduction potentials were determined for various anticonvulsants, including progabide, SL 75.102, CGS 9896, pyridazines, zonisamide, 1,2,3-triazoles, and copper complexes. The values generally were in the range of about -0.1 to -0.6 V for the protonated drugs and the metal complexes. Reduction potentials provide information on the feasibility of electron transfer (ET) in vivo. If the value is relatively positive (greater than about -0.6 V), the agent can act catalytically as an electron acceptor from an appropriate cellular donor. A concomitant favorable influence on abnormal neuronal processes associated with epilepsy could occur. We describe ET as a possible mode of action of anticonvulsants as well as some antiepileptic agents with no electrochemical data based on this hypothetical ET approach.  相似文献   
8.
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   
9.
Despite low end dialysis serum phosphate levels (Pe) the control of phosphate retention remains often unsatisfactory in dialyzed patients. In order to assess the value of Pe in dialyzed children as an indicator of dialytic phosphate removal, we studied serum phosphate kinetics over the period of dialysis and post dialysis and compared these with urea kinetics. A multicenter study was conducted in the 21 French pediatric hemodialysis units and included 144 children under 15 years of age. Blood urea and phosphate concentrations were measured at the beginning, at 45 min later, at the end of dialysis, and 30 min post dialysis. At 60 min and at 360 min post dialysis measurements were made only for a subgroup of 12 children. From the serum levels, reduction ratios for urea (URR) and phosphate (PRR) and post dialysis rebound for urea (PDUR) and phosphate (PDPR) were calculated. URR (over the dialysis session, 72%±9%) was higher than PRR (47%±12%). Moreover, urea removal continued throughout the dialysis period, while most of the reduction in phosphate occurred in the initial dialysis period. Post dialysis urea rebound was limited to the 60th min post dialysis, whereas post dialysis phosphate rebound occurred until the 360th min post dialysis; by this time the serum phosphate levels had almost reached the predialysis levels. In summary, serum phosphate kinetics over dialysis and post dialysis periods in children appear to be misleading for the quantification of phosphate removal, i. e., phosphate clearance is a poor indicator of dialytic phosphate removal. Received September 21, 1995; received in revised form and accepted June 11, 1996  相似文献   
10.
Summary Pain syndromes of the lumbar spine are one of the main problems in orthopedic practice. The therapeutic effect of NSAIDs is not subject to doubt in this connection.But considering that the application of NSAIDs is frequently associated with side effects, a reduction of dosage would be to the patient's benefit. Clinical studies have shown that concomitant treatment with vitamins B1, B6, B12 and diclofenac leads to a more efficient pain relief than treatment using diclofenac alone and thus provides the possibility of saving NSAIDs.This clinical trial was carried out in order to determine whether these results can also be achieved when a reduced dosage of diclofenac (75 mg daily) is used.123 patients with acute pain syndromes of the lumbar spine were treated with either B-vitamins and diclofenac or diclofenac alone for a maximum of 7 days. There was the option to terminate therapy in the trial after 3–4 days in the case of total pain relief.45 patients could stop the treatment due to remission of symptoms. 30 patients belonged to the combination therapy group, the other 15 took diclofenac alone; this difference is statistically significant (p< 0.05).All parameters concerning pain relief and movement of the vertebral column showed statistically significant differences in favour of the B-vitamin-diclofenac-combination, too.The results document the positive influence of B-vitamins on painful vertebral syndromes and indicate that B-vitamins contribute to saving of NSAIDs by shortening the treatment time and reducing daily NSAID-dosage.
  相似文献   
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