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1.
BackgroundAccurate preoperative planning is a key component of successful total hip arthroplasty (THA). The purpose of the present study was to compare the accuracy and reliability of three-dimensional (hipEOS) and common digital two-dimensional (TraumaCad) templating with special focus on stem morphology.Methods51 patients undergoing THA were randomized to two groups. Preoperative planning was performed on 23 patients with hipEOS (3D) and on 28 patients with TraumaCad (2D) planning software. Planning results were compared with the implanted component size. Inter- and intraobserver reliability as well as planning accuracy of both planning methods with special focus on straight and short stem design were recorded.ResultsIntraobserver reliability of both planning methods was good for component planning (ICC2,1: 0.835-0.967). Interobserver ICC2,1 for stem and cup planning were higher for 3D templating (3D ICC2,1: 0.906-0.918 vs. 2D ICC2,1: 0.835-0.843). Total stem and cup size predictions were within 2 sizes for 3D and within 3 sizes for 2D planning. Comparing short stem planning accuracy of both planning methods, absolute difference between implanted and planned component size was significantly lower in 3D planning (P = .029). There was no significant difference in straight stem (P = .935) and cup (P = .954) planning accuracy.ConclusionOur findings suggest that 3D templating with hipEOS software has a good overall reliability and may have a better planning accuracy of short stem prostheses than digital templating with TraumaCad software. Assuming that the number of implanted short stem prostheses will further increase in coming years, a more precise planning with 3D technique can contribute to improve surgery outcome.  相似文献   
2.
We present a case of large, primary malignant melanoma of the female urethra with poor prognosis in this case report. Malignant melanoma is one of the rare tumors of the female urethra and accounts for 0.2% of all malignant melanoma cases. Large (5.6 cm in diameter), primary malignant melanoma of the female urethra is exceedingly rare.  相似文献   
3.
The effects of unilateral testicular torsion on the blood flow of the contralateral testis were investigated. Fourteen adult male dogs were recruited. Seven dogs underwent unilateral testicular torsion of 4 h duration, and the other seven dogs had a control operation. Testicular blood flow was determined by colour Doppler ultrasonography before and after the testicular torsion. Bilateral orchidectomy was performed at the end of the study and histopathological changes were evaluated. Values of peak systolic velocity, end diastolic velocity, and resistive index were not statistically significant between ipsilateral and contralateral testes in the study group (p > 0.05). On comparison with the control group, blood flow in the contralateral testes showed no statistically significant difference (p > 0.05). Oedema and congestion were seen on ipsilateral testes in the study group. No histopathological changes were noted on the contralateral testes. Minimal oedema and congestion secondary to manipulation were found in the control operation testes. We conclude that unilateral testicular torsion does not decrease contralateral testicular blood flow as shown by colour Doppler ultrasonography.  相似文献   
4.

Objective

The combination of repetitive transcranial magnetic stimulation (rTMS), a non-pharmacological form of therapy for treating major depressive disorder (MDD), and electroencephalogram (EEG) is a valuable tool for investigating the functional connectivity in the brain. This study aims to explore whether pre-treating frontal quantitative EEG (QEEG) cordance is associated with response to rTMS treatment among MDD patients by using an artificial intelligence approach, artificial neural network (ANN).

Methods

The artificial neural network using pre-treatment cordance of frontal QEEG classification was carried out to identify responder or non-responder to rTMS treatment among 55 MDD subjects. The classification performance was evaluated using k-fold cross-validation.

Results

The ANN classification identified responders to rTMS treatment with a sensitivity of 93.33%, and its overall accuracy reached to 89.09%. Area under Receiver Operating Characteristic (ROC) curve (AUC) value for responder detection using 6, 8 and 10 fold cross validation were 0.917, 0.823 and 0.894 respectively.

Conclusion

Potential utility of ANN approach method can be used as a clinical tool in administering rTMS therapy to a targeted group of subjects suffering from MDD. This methodology is more potentially useful to the clinician as prediction is possible using EEG data collected before this treatment process is initiated. It is worth using feature selection algorithms to raise the sensitivity and accuracy values.  相似文献   
5.
Therapeutic drug monitoring (TDM) is used to determine the concentration of drug in plasma/serum to adjust the dose of the therapeutic drug. Selective and sensitive analytical methods are used to determine drug and metabolite levels for the successful application of TDM. The aim of the study was to develop and validate using LC‐MS/MS to analyse quantitative assay of escitalopram (S‐CT) and metabolites in human plasma samples. In order to provide a convenient and safe treatment dose, it was aimed to determine the levels of S‐CT and its metabolites in the patients’ plasma. A new method with short sample preparation and analysis time was developed and validated using LC‐MS/MS to analyse quantitative assay of S‐CT and its metabolites in plasma. Also, plasma samples of 30 patients using 20 mg S‐CT between the ages of 18 and 65 years were analysed by the validated method. The mean values of S‐CT, demethyl escitalopram and didemethyl escitalopram in plasma of patients were 27.59, 85.52 and 44.30 ng/mL, respectively. At the end of the analysis, the metabolic ratio of S‐CT and metabolites was calculated. It is considered that the method for the quantitative analysis of S‐CT and its metabolites in human plasma samples may contribute to the literature on account of its sensitive and easy application. Additionally, the use of our data by physicians will contribute to the effective drug treatment for their patients who take S‐CT.  相似文献   
6.
Background. In this study, we endeavored to determine whether the incidence of cholelithiasis (CL) was increased in chronic renal failure (CRF) patients with secondary hyperparathyroidism on a peritoneal dialysis (PD) program. We also evaluated the factors that might have some influence on the development of CL. Methods. A total of 59 CRF patients undergoing PD were included in the study. We studied the following groups to determine whether parathyroid hormone (PTH) levels were increased in CRF-PD patients: twenty patients with secondary hyperparathyroidism (group 1) and 39 patients with normal PTH levels (group 2). PTH levels were maintained at three times the upper limit of normal. Biochemical parameters were obtained for each CRF-PD patient. All patients underwent abdominal ultrasonography to screen for the presence of cholelithiasis. For statistical analysis, χ2, t test, and logistic regression analysis were used; p < 0.05 was considered as significant. Results. We found an almost ten times higher incidence (25% vs. 2.6%) of CL in group 1 patients with statistical significance (p = 0.007). When the incidence of CL according to sex, creatinine, and PTH levels were considered, female gender, creatinine, and PTH levels were higher in group 1, which was also significant statistically. No significant relationship was detected between gallbladder stone formation and the other analyzed biochemical parameters. Conclusions. We found that the incidence of CL in CRF-PD patients with secondary hyperparathyroidism was higher than CRF-PD patients with normal PTH levels. It was also detected that female gender, high creatinine levels, and elevated PTH levels might influence the development of CL in CRF-PD patients.  相似文献   
7.
8.
This study compared the safety and efficacy of the on-demand (OD) use of sertraline (50 mg), sertraline (100 mg) and dapoxetine (30 mg), and the daily use of sertraline (50 mg) in the treatment of patients with premature ejaculation (PE). This prospective randomised study involved 120 lifelong PE patients (intravaginal ejaculatory latency time [IELT]: <1 min; Arabic Index of Premature Ejaculation [AIPE] score: < 30) without secondary causes of PE, identified between March 2018 and May 2020. Patients were divided into 4 groups (30 patients per group) and treated for 8 weeks. Assessments were conducted using the AIPE form as a diagnostic tool. Sertraline (50 mg, daily; 196.7 ± 115.5 s) and sertraline (100 mg, OD; 173.3 ± 97.0 s) had similar IELT and AIPE scores. The latter groups had better results in comparison with sertraline (50 mg, OD; 100.5 ± 54.4 s) and dapoxetine (93.7 ± 53.5 s; p < 0.01). Sertraline (100 mg, OD) had a similar efficacy to that of sertraline (50 mg, daily) and was more effective than sertraline (50 mg, OD) and dapoxetine (30 mg, OD). Sertraline (100 mg, OD) can be considered in the treatment of lifelong PE treatment, having tolerable side effects.  相似文献   
9.

Objective

Many applications such as biomedical signals require selecting a subset of the input features in order to represent the whole set of features. A feature selection algorithm has recently been proposed as a new approach for feature subset selection.

Methods

Feature selection process using ant colony optimization (ACO) for 6 channel pre-treatment electroencephalogram (EEG) data from theta and delta frequency bands is combined with back propagation neural network (BPNN) classification method for 147 major depressive disorder (MDD) subjects.

Results

BPNN classified R subjects with 91.83% overall accuracy and 95.55% subjects detection sensitivity. Area under ROC curve (AUC) value after feature selection increased from 0.8531 to 0.911. The features selected by the optimization algorithm were Fp1, Fp2, F7, F8, F3 for theta frequency band and eliminated 7 features from 12 to 5 feature subset.

Conclusion

ACO feature selection algorithm improves the classification accuracy of BPNN. Using other feature selection algorithms or classifiers to compare the performance for each approach is important to underline the validity and versatility of the designed combination.  相似文献   
10.
ObjectivePopliteal venous aneurysms are uncommon but potentially fatal abnormalities, since they can cause pulmonary emboli. Here, we report a case of a popliteal venous aneurysm of the right popliteal fossa.MethodIn a 32-year-old healthy male complaining of a localised swelling and pain in his right popliteal fossa, duplex ultrasonography and angio-computed tomography revealed a giant popliteal vein aneurysm. The popliteal fossa was surgically explored and aneurysm was resected partially and sutured through posterior approach.ResultsRecovery was uneventful and patient still remains asymptomatic. Further duplex ultrasonography follow-ups revealed patency of popliteal vein without thrombotic changes in 1st, 6th, 12th and 15th months. Additionally, no dilatation of the operated vein segment has been observed in the follow-up ultrasound studies.ConclusionSurgical repair of popliteal venous aneurysms can be performed safely. Partial aneurysm resection together with lateral venorrhaphy is preferred. Due to pulmonary thrombo-embolic complication risks, we recommend surgery in early stages.  相似文献   
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