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121.
PURPOSE: The need to develop new methods of surgical training combined with advances in computing has led to the development of sophisticated virtual reality surgical simulators. The PERC Mentortrade mark is designed to train the user in percutaneous renal collecting system access puncture. We evaluated and established face, content and construct validation of the simulator in this task. MATERIALS AND METHODS: A total of 63 trainees underwent baseline testing on the simulator, consisting of percutaneous renal puncture followed by the introduction of a guidewire into the collecting system. Subjects were then randomized to an intervention arm, in which they underwent 2, 30-minute training sessions on the simulator, and a control arm, in which no further training was given, followed by repeat testing. Performance was assessed using a global rating scale and by virtual reality derived parameters. RESULTS: There were no significant differences between the 2 groups with respect to baseline measures. Subjects who underwent training with the simulator demonstrated significant improvement in objective and subjective parameters compared to their baseline performance and compared to the untrained control group. Spearman rank correlations demonstrated a significant relationship between multiple parameters of the objective and subjective data. CONCLUSIONS: Training on the simulator improves virtual reality skills. It may allow trainees to develop the basic skills necessary to perform percutaneous renal collecting system access. Face and content validity were demonstrated and construct validity was supported by establishing convergent validity.  相似文献   
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The treatment of chronic hepatitis C is relatively unsatisfactory and many patients have turned to unproven alternative medicines to modify the course of their illness. We report a study of a Chinese herbal medicine preparation CH-100 in the management of chronic hepatitis C. Patients with documented chronic hepatitis C were randomly allocated to receive active herbal or placebo tablets (five tablets thrice daily). Patients were followed monthly and evaluated by a Western and a traditional Chinese medical practitioner. Therapy was monitored by measurement of liver function tests, creatinine and full blood count on a monthly basis. Twenty patients in each group were well matched for age, sex, duration of illness, previous interferon therapy and alcohol intake. Active Chinese herbal medication was associated with a signi?cant reduction in alanine aminotransferase (ALT) levels over the 6 month study period (P<0.03). No patient cleared the virus but four normalized their ALT on treatment. Appropriately prescribed Chinese herbal medicine may have a role in the management of chronic hepatitis C and further controlled studies are indicated.  相似文献   
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采用极角混合设计技术,模拟溶质色谱保留行为的数学模型,用预测优化流动相实验,对溶质色谱保留行为的数学模型进行修正。通过数次预测、迭代、修正数学模型,提高模型的拟合精度,采用多目标优化指标,计算机辅助,寻求三元流动相的最佳组成。首次利用可编程序紫外检测器的时间程序检测功能,提高微量组分的检测灵敏度,成功地解决了两种长效避孕药制剂的定量分析。  相似文献   
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Background

Most early stage kidney cancers are renal cell carcinomas (RCCs), and most are diagnosed incidentally by imaging as small renal masses (SRMs). Indirect evidence suggests that most small RCCs grow slowly and rarely metastasize.

Objective

To determine the progression and growth rates for newly diagnosed SRMs stratified by needle core biopsy pathology.

Design, setting, and participants

A multicenter prospective phase 2 clinical trial of active surveillance of 209 SRMs in 178 elderly and/or infirm patients was conducted from 2004 until 2009 with treatment delayed until progression.

Intervention

Patients underwent serial imaging and needle core biopsies.

Measurements

We measured rates of change in tumor diameter (growth measured by imaging) and progression to ≥4 cm, doubling of tumor volume, or metastasis with histology on biopsy.

Results and limitations

Local progression occurred in 25 patients (12%), plus 2 progressed with metastases (1.1%). Of the 178 subjects with 209 SRMs, 127 with 151 SRMs had > 12 mo of follow-up with two or more images, with a mean follow-up of 28 mo. Their tumor diameters increased by an average of 0.13 cm/yr. Needle core biopsy in 101 SRMs demonstrated that the presence of RCC did not significantly change growth rate. Limitations included no central review of imaging and pathology and a short follow-up.

Conclusions

This is the first SRM active surveillance study to correlate growth with histology prospectively. In the first 2 yr, the rate of local progression to higher stage is low, and metastases are rare. SRMs appear to grow very slowly, even if biopsy proven to be RCC. Many patients with SRMs can therefore be initially managed conservatively with serial imaging, avoiding the morbidity of surgical or ablative treatment.  相似文献   
128.
Study Type – Therapy (case series)
Level of Evidence 4 What’s known on the subject? and What does the study add? Whilst the technique of robot‐assisted radical prostatectomy has rapidly been adopted by surgeons there is little information on techniques used for quality control when a surgeon is learning this new surgical technique. Cummulative summation graphs have been used in cardiothoracic surgery to monitor complications with good effect and have been shown to be useful in monitoring outcomes from cystectomy. We demonstrate that using the technique of cumulative summation graphs a surgeon can monitor their progress prospectively through a learning curve without having to wait to perform a retrospective analysis. This study demonstrates that margin positive rates in radical prostatectomy can be monitored in real time and adjustments in technique applied to allow a surgeon to continually monitor and improve their surgical results.

OBJECTIVE

? To explore the usefulness of cumulative summation (CUSUM) graphs for monitoring positive surgical margin (PSM) rates during a surgeon’s transition from open to robot‐assisted radical prostatectomy (RARP).

PATIENTS AND METHODS

? Data were prospectively collected from patients undergoing RARP by a single surgeon. ? Preoperatively all patients were either low or moderate risk under the D’Amico classification system. ? A CUSUM graph was charted retrospectively to analyse the PSM rate in patients undergoing RARP for pathological stage T2 (pT2) disease. ? Acceptable and unacceptable PSM rates were set at 10% and 15% respectively.

RESULTS

? From a cohort of 226 patients, 158 patients with pT2 disease were selected. The mean (range) age of these patients was 59.2 (39–73) years, the median (range) Gleason score was 6 (4–9), the mean (range) PSA was 6.43 (0.52–17.5) ng/mL and the mean (range) prostate volume was 44 (18–120) cm3. In all, 21 patients had PSMs (13%). ? CUSUM graphs were produced and clearly demonstrated the change in PSM rate over time.

CONCLUSION

? CUSUM graphs are a novel and useful visual representation of the learning curve for surgeons. ? PSM rates in patients with pT2 disease are a good outcome to monitor using CUSUM graphs as they are binary and lack the confounding factors associated with other outcomes such as continence and erectile dysfunction. ? We advocate the use of CUSUM graphs as a method of quality assurance with the introduction of a robotics programme.  相似文献   
129.

Background  

The scaphoid bone is the most commonly fractured of the carpal bones. In the Netherlands 90% of all carpal fractures is a fracture of the scaphoid bone. The scaphoid has an essential role in functionality of the wrist, acting as a pivot. Complications in healing can result in poor functional outcome. The scaphoid fracture is a troublesome fracture and failure of treatment can result in avascular necrosis (up to 40%), non-union (5-21%) and early osteo-arthritis (up to 32%) which may seriously impair wrist function. Impaired consolidation of scaphoid fractures results in longer immobilization and more days lost at work with significant psychosocial and financial consequences.  相似文献   
130.
BACKGROUND AND PURPOSE: The gold standard treatment for upper-tract transitional-cell carcinoma is radical nephroureterectomy, but management of the distal ureter is not standardized. Two treatment options to detach the distal ureter are open cystotomy (OC) and excision of a bladder cuff or transurethral incision of the ureteral orifice (TUIUO). We compared the clinico-pathologic outcomes of these two techniques. PATIENTS AND METHODS: Hospital records were reviewed on all 51 patients who had undergone open or laparoscopic nephroureterectomy at our institution between 1 January 1990 and 30 June 2005. Patient demographics, intraoperative parameters, and pathology data were collected. The mean follow-up was 23.2 months (range 4.5-75 months) and 22.1 months (range 1-50 months) for the OC and TUIUO groups, respectively. There were no significant differences in sex, age at operation, American Society Anesthesiologists risk score, previous transitional-cell tumors, pathologic tumor grade and stage, or metastatic disease status in the two groups. RESULTS: Five patients had an unplanned incomplete ureterectomy. The bladder recurrence rates were similar in the OC group (22.2%; 6/27) and the TUIUO group (26.3%; 5/19). There were no pelvic recurrences in either group. Four of the five patients who had an incomplete ureterectomy had tumor recurrences, three in the form of metastatic disease. CONCLUSION: Management of the distal ureter by TUIUO in appropriate patients offers the same rate of bladder recurrence as OC. Incomplete ureterectomy results in a significantly higher rate of recurrence, often associated with the development of metastatic disease.  相似文献   
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