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41.
The aim of this study was to determine if DNA polymorphism within runt-related gene 2 (RUNX2)/core binding factor A1 (CBFA1) is related to bone mineral density (BMD). RUNX2 contains a glutamine-alanine repeat where mutations causing cleidocranial dysplasia (CCD) have been observed. Two common variants were detected within the alanine repeat: an 18-bp deletion and a synonymous alanine codon polymorphism with alleles GCA and GCG (noted as A and G alleles, respectively). In addition, rare mutations that may be related to low BMD were observed within the glutamine repeat. In 495 randomly selected women of the Geelong Osteoporosis Study (GOS), the A allele was associated with higher BMD at all sites tested. The effect was maximal at the ultradistal (UD) radius (p = 0.001). In a separate fracture study, the A allele was significantly protective against Colles' fracture in elderly women but not spine and hip fracture. The A allele was associated with increased BMD and was protective against a common form of osteoporotic fracture, suggesting that RUNX2 variants may be related to genetic effects on BMD and osteoporosis.  相似文献   
42.
Both the numbers of children undergoing day case surgery and the type of procedures performed in this way are increasing. This expansion will only be beneficial if anaesthesia and surgery are provided with minimal post-operative morbidity e.g. postoperative delirium or nausea and vomiting. The choice of anaesthetic technique is considered critical to optimizing the service provided to patients and for this reason much research has addressed this question. This review considers the effect of anaesthetic technique on postoperative outcome in paediatric day case surgery. The outcome measures reviewed by this article are induction of anaesthesia, effects on the cardiovascular system, recovery from anaesthesia and postoperative nausea and vomiting. In each section both quantitative and qualitative outcome measures are discussed. Comparisons are made between sevoflurane and halothane, sevoflurane and propofol, propofol and halothane, desflurane and halothane and the presence or absence of nitrous oxide.  相似文献   
43.
A method for two-way serial communication with MagStim 200(2) BiStim units using LabVIEW is described. A suite of LabVIEW 'virtual instruments' which give simple and reliable control of pulse parameters and delivery is described and made freely available online. The advantages of serial control include the ability to quickly and reliably change pulse parameters during an experiment, to randomly intersperse pulses with different parameters without manually resetting the unit, to deliver pulses with a reliable temporal relationship to other external events, and to control pulse parameters interactively. An application that uses the method for adaptive control of pulse intensity is reported.  相似文献   
44.

Background

Widespread use of prostate-specific antigen screening has resulted in younger and healthier men being diagnosed with prostate cancer. Their demands and expectations of surgical intervention are much higher and cannot be adequately addressed with the classic trifecta outcome measures.

Objective

A new and more comprehensive method for reporting outcomes after radical prostatectomy, the pentafecta, is proposed.

Design, setting, and participants

From January 2008 through September 2009, details of 1111 consecutive patients who underwent robot-assisted radical prostatectomy performed by a single surgeon were retrospectively analyzed. Of 626 potent men, 332 who underwent bilateral nerve sparing and who had 1 yr of follow-up were included in the study group.

Measurements

In addition to the traditional trifecta outcomes, two perioperative variables were included in the pentafecta: no postoperative complications and negative surgical margins. Patients who attained the trifecta and concurrently the two additional outcomes were considered as having achieved the pentafecta. A logistic regression model was created to evaluate independent factors for achieving the pentafecta.

Results and limitations

Continence, potency, biochemical recurrence–free survival, and trifecta rates at 12 mo were 96.4%, 89.8%, 96.4%, and 83.1%, respectively. With regard to the perioperative outcomes, 93.4% had no postoperative complication and 90.7% had negative surgical margins. The pentafecta rate at 12 mo was 70.8%. On multivariable analysis, patient age (p = 0.001) was confirmed as the only factor independently associated with the pentafecta.

Conclusions

A more comprehensive approach for reporting prostate surgery outcomes, the pentafecta, is being proposed. We believe that pentafecta outcomes more accurately represent patients’ expectations after minimally invasive surgery for prostate cancer. This approach may be beneficial and may be used when counseling patients with clinically localized disease.  相似文献   
45.
Twenty-two patients underwent a posterior bone block distraction arthrodesis of the subtalar joint between 1999 and 2006. The indication for surgery was loss of heel height, subtalar joint arthrosis, decreased talar declination with associated tibiotalar impingement, insufficient Achilles tendon function, malalignment of the rear foot, and pain with ambulation. There were 11 male and 11 female patients with a mean age of 46.7 years (range 20 to 71). The mean follow-up period was 27.3 months (range 12 to 63.9 months). Radiographic analysis revealed a mean increase in heel height of 6.09 mm (P= .0001), 5.83 degrees (P= .12) of lateral talocalcaneal angle, 5.5 degrees (P= .06) of talar declination, and 5.23 degrees (P= .07) of calcaneal inclination. The talo-first metatarsal angle increased an average of 4.5 degrees (P= .18). There was a 95.5% union rate. Postoperative complications included nonunion in 1 patient, subsidence of graft (collapse) in 1 patient, wound dehiscence in 3 patients, painful hardware in 7 patients, sural neuritis in 1 patient, superior cluneal nerve dysfunction in 1 patient and one mild varus malunion. Posterior bone block distraction arthrodesis can be successfully used to restore heel height, realign the foot, and decrease the morbidity associated with late complications of calcaneal fractures, as well as, nonunion and/or malunion following subtalar joint arthrodesis, Charcot neuroarthropathy, and avascular necrosis of the talus. LEVEL OF CLINICAL EVIDENCE: 4.  相似文献   
46.
OBJECTIVE: To evaluate the effect of vardenafil on both erectile function (EF) and treatment satisfaction (an aspect of quality of life) in men and their partners, as erectile dysfunction (ED) has a profound effect on patients' quality of life and that of their partners, and treatment for ED tends to be focused on improving functional measures of EF. PATIENTS, SUBJECTS AND METHODS: For this randomized, double-blind, placebo-controlled trial, men with ED for >6 months, according to the USA National Institutes of Health Consensus Statement, were recruited. In all, 611 patients were randomized to treatment with either vardenafil (10 mg for 4 weeks, titrated to preferred dose, 5, 10 or 20 mg, during the next 8 weeks, and maintained at preferred dose for the following 14 weeks), or placebo. RESULTS: At 18 weeks (primary endpoint), the mean improvement in the EF domain of International Index of EF (IIEF-EF) vs baseline was significantly greater with vardenafil than placebo (12.70 vs 1.69, P < 0.001). This was accompanied by significant benefits at 26 weeks and in various secondary variables relating to sexual satisfaction. Qualitative assessment of the treatment effect revealed three categories of importance to patients: effectiveness, confidence and quality of life. There were significant linear correlations between patients' EF and treatment satisfaction, and between patients' EF and their partners' treatment satisfaction. CONCLUSIONS: Functional improvements in response to vardenafil treatment are significantly correlated with treatment satisfaction for both patients with ED and their partners. These findings apply to patients with a wide range of baseline characteristics.  相似文献   
47.
BACKGROUND: Because the course of polyoma virus-associated nephropathy (PVAN) has not been evaluated in a large cohort of patients receiving sirolimus (SRL)-based regimens, we have herein presented the incidence, clinical characteristics, and outcomes of 378 renal transplant recipients treated with SRL-based immunosuppression. METHODS: This retrospective single center study evaluated 344 kidney alone (KTX) and 34 simultaneous pancreas-kidney (SPK) transplantations performed between June 2000 and December 2004. RESULTS: At a mean follow-up of 43.3 months, six kidney (1.7%) and three kidney-pancreas (9.0%) transplanted patients displayed biopsy-proven PVAN. The mean time to diagnosis after transplantation was 18.2 months (range: 3.5-31.1 months), with a higher incidence among patients exposed (4.23%) versus not exposed to rabbit antithymocyte globulin (rATG; 0.53%; P=0.019) or SPK (9.0%) versus KTX (1.7%) recipients (odds ratio: 5.43; confidence interval: 1.29-22.8; P=0.038). Despite treatment with cidofovir, reduced immunosuppression and maintenance therapy with no agents other than SRL (C0=10.2+/-2.7 ng/dL) plus modest doses of prednisone (< or =5 mg), five patients (55.5%) experienced renal allograft failure. No rejection episodes were documented during the PVAN treatment and pancreatic function continued to be excellent among the SPK patients. CONCLUSIONS: Patients treated with SRL-based immunosuppression showed an incidence at the lower end of the range described with various other contemporaneous immunosuppressive regimens and with other cohorts not undergoing BK virus polymerase chain reaction surveillance. Exposure to rATG and SPK transplantation represented risk factors for the occurrence of PVAN, which showed a pernicious course despite withdrawal of calcineurin antagonists and/or mycophenolate mofetil.  相似文献   
48.
ObjectivesLongitudinal studies report racial disparities in prostate cancer (PCa) including greater incidence, more aggressive tumor biology, and increased cancer-specific mortality in African American (AA) men. Regret concerning primary treatment selection is underevaluated in patients with PCa. We investigated the relationships between clinicopathologic variables across racial and socioeconomic lines following robotic-assisted laparoscopic prostatectomy.Materials and methodsWe assessed treatment decisional regret using a validated questionnaire in a total of 484 white and 72 AA patients with PCa who were followed up for a median of 16.6 months post–robotic-assisted laparoscopic prostatectomy. Socioeconomic status (SES) information was aggregated from 2010 US census zip code data. Perioperative clinicopathologic characteristics and functional outcomes were compared between groups. Univariate and multivariate regression analyses were used to evaluate the influence of race, aggregate SES, and other clinical and demographic characteristics on decisional regret.ResultsThe majority (87.7%) of the population was not regretful of their decision to undergo treatment. However, a greater proportion of AA vs. white patients were regretful (20.6% vs. 11.2%, respectively; P = 0.03). AA and white men were similar on all functional, clinical, and pathologic features with the exception of younger age among AA men (56 vs. 60 y, respectively; P<0.001). Although there were significant differences in SES by race (P<0.001), regret did not differ by SES (β =?1.53; P = 0.15). Race, postoperative sexual dysfunction, pad usage, and length of hospital stay, however, were significantly associated with decisional regret.ConclusionsAA men were more regretful than white men, after adjusting for clinicopathologic characteristics and postoperative functional outcomes.  相似文献   
49.
At present there appears to be a need for research conducted on the effects of vibration on the contractile ability of skeletal muscle tissue. The aim of this study was to address this issue by examining the effects of a superimposed muscle/tendon vibration at 50.42±1.16 Hz (acceleration 13.24 ± 0.18ms-2: displacement ≈5mm) on muscular activation and maximal isometric contraction. Sixteen participants with a mean age, body mass, and height of 22 ± 4.4 years, 73.2 ± 11.7 kg and 173.1 ± 9.7 cms, respectively, were recruited for this study. Electromyography and accelerometry from the rectus femoris, and maximal isometric force data characteristics were collected from the dominant limb under conditions of vibration, and no-vibration. A superimposed 50 Hz vibration was used during the contraction phase for the maximal isometric leg extension for the condition of vibration. A one-way ANOVA revealed no significant (p > 0.05) differences between the vibration and no-vibration conditions for peak normalized EMGRMS (84.74% Vs 88.1%) values. An ANOVA revealed significant (p > 0.05) differences between the peak fundamental frequencies of the FFT between the conditions vibration (27.1 ± 12.2 Hz) and no-vibration (9.8 ± 3.5 Hz). Peak isometric force, peak rate of force development, rate of force development at times 0.05, 0.01, 0.1, 0.5 seconds, and rate of force development at 50, 75, and 90% of peak force were not significantly different. The results of this study suggest that the application of vibration stimulation at 50 Hz during the contraction does not contribute to muscle activation, or enhance force production for maximal isometric contractions.

Key Points

  • The application of a vibratory stimulation to the human body increases the normal acceleration resulting in an increase in force and a change in performance
  • This study was to address this issue by examining the effects of a direct superimposed muscle/tendon vibration at 50 Hz on isometric strength characteristics
  • No improvement or change in isometric force or rate of force development
  • No changes to peak normalized EMGRMS values
Key words: Strength, oscillations, isometric, peak, muscle activation  相似文献   
50.

Purpose

Tibial nail interlocking screw failure often occurs during delayed fracture consolidation or at early weight bearing of nailed unstable fractures, in general when high implant stress could not be reduced by other means. Is there a biomechanical improvement in long-term performance of angle stable locking screws compared to conventional locking screws for distal locking of intramedullary tibial nails?

Methods

Surrogate bones of human tibiae were cut in the distal third and distal locking of the 10 mm intramedullary tibial nail was performed with either two angle stable locking screws or two conventional locking screws in the mediolateral plane. Six specimens per group were mechanically tested under quasi-static and cyclic axial loading with constantly increasing force.

Results

Angle stable locking screw constructs exhibited significantly higher stiffness values (7,809 N/mm ± 647, mean ± SD) than conventional locking screw constructs (6,614 N/mm ± 859, p = 0.025). Angle stable locking screw constructs provided a longer fatigue life, expressed in a significantly higher number of cycles to failure (187,200 ± 18,100) compared to conventional locking screw constructs (128,700 ± 7,000, p = 0.004).

Conclusion

Fatigue performance of locking screws can be ameliorated by the use of angle stable locking screws, being especially important if the nail acts as load carrier and an improved stability during fracture healing is needed.  相似文献   
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