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21.
There is now growing evidence of cognitive weakness in female premutation carriers (between 55 and 199 CGG repeats) of the fragile X mental retardation gene, including impairments associated with executive function. While an age-related decline in assessments of executive function has been found for male premutation carriers, few studies have explored whether female carriers show a similar trajectory with age. A total of 20 female premutation carriers and 21 age- and IQ-matched healthy controls completed a battery of tasks assessing executive function tasks, including the behavioural dyscontrol scale (BDS), symbol digit modalities test (SDMT), paced auditory serial addition test (PASAT), Haylings sentence completion test and the digit span task (forward and backward). Performance was compared between premutation carriers and healthy controls, and the association between task performance and age was also ascertained. Compared to controls, female premutation carriers had significant impairment on the BDS, SDMT, PASAT, and Haylings sentence completion task, all of which rely on quick, or timed, responses. Further analyses revealed no significant association between age and task performance for either premutation carriers or controls. This study demonstrates that a cohort of female premutation carriers have deficits on a range of tasks of executive function that require the rapid temporal resolution of responses. We propose that the understanding of the phenotype of premutation carriers will be advanced through use of such measures.  相似文献   
22.
Chitosan is a polysaccharide scaffold used to enhance cartilage repair during treatments involving bone marrow stimulation, and it is reported to increase angiogenesis and osteogenesis in vivo. Here, we tested the hypotheses that addition of chitosan particles to the media of human bone marrow stromal cell (BMSC) cultures stimulates osteogenesis by promoting osteoblastic differentiation and by favoring the release of angiogenic factors in vitro. Confluent BMSCs were cultured for 3 weeks with 16% fetal bovine serum, ascorbate-2-phosphate and disodium β-glycerol phosphate, in the absence or presence of dexamethasone, an anti-inflammatory glucocorticoid commonly used as an inducer of BMSC osteoblast differentiation in vitro. As expected, dexamethasone slowed cell division, stimulated alkaline phosphatase activity and enhanced matrix mineralization. Added chitosan particles accumulated intra- and extracellularly and, while not affecting most osteogenic features, they inhibited osteocalcin release to the media at day 14 and interfered with mineralized matrix deposition. Interestingly, dexamethasone promoted cell attachment and suppressed the release and activation of matrix metalloprotease-2 (MMP-2). While chitosan particles had no effect on the release of angiogenic factors, dexamethasone significantly inhibited (p < 0.05 to p < 0.0001) the release of vascular endothelial growth factor (VEGF), granulocyte-macrophage colony stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-α), interleukins 1β, 4, 6, and 10 (IL-1β, IL-4, IL-6, IL-10), and a host of other inflammatory factors that were constitutively secreted by BMSCs. These results demonstrate that chitosan particles alone are not sufficient to promote osteoblast differentiation of BMSCs in vitro, and suggest that chitosan promotes osteogenesis in vivo through indirect mechanisms. Our data further show that continuous addition of dexamethasone promotes osteoblastic differentiation in vitro partly by inhibiting gelatinase activity and by suppressing inflammatory cytokines which result in increased cell attachment and cell cycle exit.  相似文献   
23.

Background

Laparoscopic-endoscopic single-site surgery (LESS) represents the closest surgical technique to scar-free surgery.

Objective

To assess the feasibility of LESS radical nephrectomy (LESS-RN).

Design, setting, and participants

Ten patients with body mass index (BMI) ≤30 underwent LESS-RN for renal tumour by two experienced laparoscopists.

Surgical procedure

TriPort (Olympus Winter &; Ibe, Hamburg, Germany) was inserted through a transumbilical incision. A combination of standard laparoscopic instruments and flexible grasper and scissors was used. A 5-mm 30° camera was also used. The standard laparoscopic transperitoneal nephrectomy technique was performed.

Measurements

Patient demographics, operative details, and final pathology were prospectively recorded. Postoperative evaluation of pain and use of analgesic medication were recorded.

Results and limitations

Ten cases were successfully accomplished (two right-sided tumours and eight left-sided tumours; tumour diameter ranges: 4–8 cm). The mean patient age was 63.5 yr (22–77 yr), and median BMI was 23.56 (18.2–26.6). The mean operative time was 146.4 min (120–180 min), and the mean blood loss was 202 ml (50–900 ml). Pathological examination observed organ-confined T1 renal cell carcinoma in nine cases and pT3b tumour in one case. One bleeding complication occurred. Limitations regarding the intraoperative instrument ergonomics and the requirement for ambidexterity of the surgeon were noted.

Conclusions

LESS-RN proved to be safe and feasible. Further clinical investigation in comparison to the established techniques should take place to evaluate the outcome of LESS-RN.  相似文献   
24.
OBJECTIVES: Based on our recently published anatomic studies, we present the most recent refinement of the endoscopic extraperitoneal radical prostatectomy (EERPE), the intrafascial nerve-sparing EERPE (nsEERPE). METHODS: As part of the intrafascial technique, the dissection plane is directly on the prostatic capsule, freeing the prostate laterally from its thin surrounding fascia that contains small vessels and nerves. The technique enables puboprostatic ligament preservation, leaving intact endopelvic fascia, periprostatic fascia, and neurovascular bundles. The operation was performed in 150 patients with indications for nerve-sparing procedure. RESULTS: The mean operative time was 131 min (range: 50-210 min) and the mean catheterization time was 5.9 d (range: 4-20 d). Twelve months postoperatively, 94.3% of the patients were continent (no need for pads), 4.6% had minimal stress incontinence, and one patient required >2 pads/d. At the 12-mo follow-up, the potency rates (erections sufficient for intercourse with or without the use of phosphodiesterase 5 [PDE5] inhibitors) of the patients who underwent bilateral intrafascial nsEERPE were 89.7% (age: 44-55 yr), 81.1% (age: 56-65 yr), and 61.9% (age: >65 yr). Positive surgical margins in pT2 and pT3 tumors were 4.5% and 29.4%, respectively. CONCLUSIONS: The intrafascial nsEERPE enables the dissection of the prostate with limited trauma to the surrounding fascias and the enclosed neurovascular bundles. We propose that the preserved neurovascular bundles with intrafascial nsEERPE are more viable. The results advocate this proposition.  相似文献   
25.
The use of nonpenetrating clips (NPC) for vascular anastomosis is quickly becoming accepted. Studies attest to decreased anastomotic time, comparable patency rates, and decreased blood loss. Few human studies on the use of NPC have been done to date. The purpose of this study was to evaluate primary patency rates, operative time, and complications associated with NPC compared to those with standard sutures for arterial venous graft (AVG). We retrospectively reviewed the clinical course of 82 patients with a mean age of 45 years (range, 22 to 87) from February 1996 to July 1999. All patients underwent upper extremity AVG construction. The procedures were performed at a single institution, by a single, well-experienced surgeon who has extensive experience with NPC. Primary patency rates, operative time, and complications were analyzed. Overall thrombotic incidence of AVG when NPC were used (27/48, 56%) was similar to that of sutures (17/34, 50%). Thrombotic incidence within the first year was similar as well (23/48, 48% and 13/34, 38%). The mean time to primary thrombosis was similar in both groups (6.9 and 6.8 months). The operative time required to construct an AVG with NPC (83 min) was significantly less than that with sutures (96 min) (p = 0.015). There was no significant difference in incidence of graft infection or pseudoaneurysm formation. NPC for AVG reduced operative time and resulted in primary patency and complication rates similar to those associated with use of sutures. The mean time to primary thrombosis was similar for both groups. Our findings suggest an intimai hyperplastic response of a similar nature resulting in thrombosis of both NPC and sutured AVGs. Presented at the Twenty-fifth Annual Meeting of the Peripheral Vascular Surgery Society, Toronto, Ontario, Canada, June 10, 2000.  相似文献   
26.
Stolzenburg JU  Rabenalt R  Do M  Horn LC  Liatsikos EN 《European urology》2006,49(3):491-8; discussion 499-500
PURPOSE: To establish a teaching program for the performance of endoscopic extraperitoneal radical prostatectomy (EERPE) that would ascertain the safe and efficacious training of residents with no previous experience with open pelvic surgery. MATERIALS AND METHODS: The technique of EERPE was divided in 12 segments with 5 levels of difficulty. We thus designed a training program, where the resident learned the procedure in a mentor-defined schedule. During each educational EERPE, the trainee only performed the operative steps corresponding to his acquired skill level. The mentor performed the remaining parts of the EERPE, with the trainee assisting. The first 50 and consequent 100 cases performed by the residents were compared to the first 50 and last 100 cases (cases 521-621) performed by the mentor. RESULTS: Two residents with no prior experience with open pelvic surgery participated in the study, and required 43 and 38 procedures respectively, until they were considered to be competent. The initial 50 procedures performed completely independently by the residents had mean operative times of 176 and 173 minutes. There were 2 intraoperative rectal injuries (one patient developed recto-urethral fistula), and 1 hemorrhage, and 1 lymphocele, postoperatively. The positive margin rate for pT2 disease was 14.3 and 11.5%, and for pT3 tumors 38.8 and 29.1%, respectively. After an additional 100 procedures operated by the same residents, mean operative times were 142 and 146 minutes. There was one patient who needed a transfusion. Postoperative complications requiring re-intervention were 1 hemorrhage, 2 anastomotic leakages and 4 symptomatic lymphoceles. The positive margin rate for pT2 disease was 12.8% and 6.5%, and for pT3 tumors 33.3% and 26.3% respectively. No statistical significant differences were observed when comparing with the mentors cases. CONCLUSION: We have showed that residents with no prior experience in open surgery of the pelvis can adhere to the modular training scheme and successfully perform the EERPE procedure with similar risk of complications compared to the tutor.  相似文献   
27.
28.
In Vietnam, a pilot ‘smoke-free hospital’ model was implemented in nine hospitals in 2009–2010 to supply lessons learned that would facilitate a replication of this model elsewhere. This study aimed to assess smoking patterns among health professionals and to detect levels of second-hand smoke (SHS) exposure within hospital premises before and after the ‘smoke-free hospital’ model implementation. A pre- and post-intervention cross-sectional study was conducted in nine purposively selected hospitals. Air nicotine levels were measured using passive nicotine monitors; smoking evidence was collected through on-site observations; and smoking patterns were assessed through interviews with health workers. Despite the ‘smoke-free hospital’ intervention, smoking continued among health-care workers who were former smokers. Specifically, self-reported smoking prevalence significantly decreased post-intervention, but the number of daily cigarettes smoked at workplaces among male health workers remained unchanged. Post-intervention, smoking was more likely to take place outside buildings and cafeterias. However, air nicotine levels in the doctors' lounges and in emergency departments did not change post-intervention. Air nicotine levels at other sites decreased minimally. Tailored tobacco cessation programmes, targeting current smokers and mechanisms to enforce non-smoking, should be established to meet requirements of Vietnam's comprehensive National Tobacco Control Law effective in May 2013.  相似文献   
29.
Dietary assessment, while traditionally based on pen-and-paper, is rapidly moving towards automatic approaches. This study describes an Australian automatic food record method and its prototype for dietary assessment via the use of a mobile phone and techniques of image processing and pattern recognition. Common visual features including scale invariant feature transformation (SIFT), local binary patterns (LBP), and colour are used for describing food images. The popular bag-of-words (BoW) model is employed for recognizing the images taken by a mobile phone for dietary assessment. Technical details are provided together with discussions on the issues and future work.  相似文献   
30.
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