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991.
Varicocele is the abnormal dilation of venous pampiniform plexus and internal spermatic vein. Its prevalence in the adolescent period is almost equal to the prevalence of adult age. That is why the disease is accepted to appear in early adolescence and does not disappear spontaneously. Varicocele is established to be the most common cause of infertility in the adulthood period in terms of the testicular and/or epididymal damages it causes. Besides, malfunctioning of testis and/or epididymis cannot be blamed as the one and only reason of infertility. One major reason of the male infertility is vas deferens motility disorders. There is limited data in the literature investigating the effects of varicocele on the vas deferens motility. The aim of the study is to evaluate not only the motility defects of vas deferens for the period of varicocele, but also the effects of surgical varicocele correction on vas deferens motility. Thirty male Wistar-Albino rats were allocated to five groups. In the control group (Gr C, n = 6) bilateral vas deferens strips were harvested without any surgical intervention. Using the partial left renal vein obstruction technique, the experimental varicocele model was performed for the other four groups. Varicocele was apparent for these animals after the fourth week of the venous ligation. Bilateral vas deferens strips of varicocele group (Gr V, n = 6) were harvested. The rest of the animals having varicocele underwent relaparotomies. Three different surgical procedures were performed to these animals. The animals of group P (Gr P, n = 6) and group I (Gr I, n = 6) underwent Palomo and Ivanissevich procedures, respectively, for varicocele correction. And the animals of group S (Gr S, n = 6) underwent sham operation. After 4 weeks of relaparotomies, bilateral vas deferens strips of all three groups harvested. The electrical field stimulation (EFS) induced responses of all vas deferens strips as well as exogenous drug induced responses were recorded and analysed. The results of the study showed that the varicocele significantly inhibited the first phase of biphasic response of vas deferens in the ipsilateral side. However the correction of varicocele, free from surgical technique, ameliorated the affected first phase of EFS induced biphasic response in the ipsilateral side. The results of this study suggest that varicocele can be the reason of male infertility by not only causing testicular and/or epididymal damages but also triggering vas deferens motility defects. The correction of varicocele free from surgical technique may reverse the damaging of the vas deferens. Therefore when indicated surgical correction of varicocele is essential. It seems that varicocele surgery does not only prevent late term testicular and/or epididymal damages but also avoids vas deferens motility defects. Presented in the Scientific Session III (Young Investigator Award) in the 8th European Congress of Paediatric Surgery in Turin, Italy between 16 and 19 May 2007.  相似文献   
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Despite advances in transplantation techniques and the quality of post-transplantation care, opportunistic infections remain an important cause of complications. Pneumocystis jirovecii (P. jirovecii) is an opportunistic organism, represents an important cause of infections in heart transplantation patients. Almost 2% to 10% of patients undergoing cardiac transplantation have Pneumocystis pneumonia. Prophylaxis is essential after surgery. Various prophylaxis regimes had been defined in past and have different advantages. Trimethoprim/sulfamethoxazole (TMP/SMX) has a key role in prophylaxis against P. jirovecii. Generally, although TMP/SMX is well tolerated, serious side effects have also been reported during its use. Pentamidine is an alternative prophylaxis agent when TMP/SMX cannot be tolerated by the patient. Structurally, pentamidine is an aromatic diamidine compound with antiprotozoal activity. Since it is not effectively absorbed from the gastrointestinal tract, it is frequently administered via the intravenous route. Pentamidine can alternatively be administered through inhalation at a monthly dose in heart transplant recipients. Although, the efficiency and safety of this drug is well studied in other types of solid organ transplantations, there are only few data about pentamidine usage in heart transplantation. We sought to evaluate evidence-based assessment of the use of pentamidine against P. jirovecii after heart transplantation.  相似文献   
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997.

Purpose

To investigate whether serum anti-müllerian hormone (AMH), follicle stimulating hormone (FSH), or antral follicle count (AFC) are predictive for clinical pregnancy in in vitro fertilization (IVF) patients.

Methods

Serum AMH, inhibin B, FSH, luteinizing hormone (LH), estradiol (E2), prolactin, and thyroid stimulating hormone (TSH) levels and AFC of 189 women under 40 years of age were investigated. Pregnant and non-pregnant women were compared.

Results

Forty-seven (24.8 %) clinical pregnancies were observed in 189 women. There was no significant difference in terms of mean age, duration of infertility, body mass index, AMH, LH, FSH, E2, TSH, Inhibin B, AFC and total oocyte number between women who did and who did not become pregnant. Additionally, there was no significant difference in clinical pregnancy rates between the quartiles of AMH, FSH and AFC. (P values were 0.668, 0.071, and 0.252, respectively.)

Conclusion

Serum AMH and FSH, and AFC cannot predict clinical pregnancy in IVF patients under 40; the pregnancy rate tends to increase as AMH increases, although this remains non-significant.  相似文献   
998.
In this paper, a Computer Aided Detection (CAD) system based on three-dimensional (3D) feature extraction is introduced to detect lung nodules. First, eight directional search was applied in order to extract regions of interests (ROIs). Then, 3D feature extraction was performed which includes 3D connected component labeling, straightness calculation, thickness calculation, determining the middle slice, vertical and horizontal widths calculation, regularity calculation, and calculation of vertical and horizontal black pixel ratios. To make a decision for each ROI, feed forward neural networks (NN), support vector machines (SVM), naïve Bayes (NB) and logistic regression (LR) methods were used. These methods were trained and tested via k-fold cross validation, and results were compared. To test the performance of the proposed system, 11 cases, which were taken from Lung Image Database Consortium (LIDC) dataset, were used. ROC curves were given for all methods and 100% detection sensitivity was reached except naïve Bayes.  相似文献   
999.

Purpose

The aims of this study were to evaluate sagittal plane alignment in patients with chondromalacia patella via magnetic resonance imaging (MRI), analyse the relationships between the location of the patellar cartilaginous lesions and sagittal alignment and finally investigate the relationships between the sagittal plane malalignment and patellofemoral loadings using by finite element analysis.

Methods

Fifty-one patients who were diagnosed with isolated modified Outerbridge grade 3–4 patellar chondromalacia based on MRI evaluation and 51 control subjects were evaluated. Chondromalacia patella patients were divided into three subgroups according to the chondral lesion location as superior, middle and inferior. The patella–patellar tendon angle (P–PT) was used for evaluation of sagittal alignment of patellofemoral joint. Each subgroup was compared with control group by using P–PT angle. To investigate the biomechanical effects of sagittal plane malpositioning on patellofemoral joint, bone models were created at 30°, 60° and 90° knee flexion by using mean P–PT angles, which obtained from patients with chondromalacia patellae and control subjects. The total loading and contact area values of the patellofemoral joints were investigated by finite element analysis.

Results

The mean age of all participants was 52.9 ± 8.2 years. The mean P–PT angle was significantly lower in chondromalacia group (142.1° ± 3.6°) compared to control group (144.5° ± 5.3°) (p = 0.008). Chondral lesions were located in superior, middle and inferior zones in 16, 20 and 15 patients, respectively. The mean P–PT angles in patients with superior (141.8 ± 2.7) and inferior subgroups (139.2 ± 2.3) were significantly lower than the values in the control group (p < 0.05). The contact area values were detected higher in models with chondromalacia than in the control models at the same flexion degrees. There were increased loadings at 30° and 90° flexions in the sagittal patellar tilt models.

Conclusion

This study revealed that sagittal plain malpositioning of the patellofemoral joint might be related to chondromalacia, especially in the presence of lesions in the upper and lower part of the patella. This condition leads to supraphysiological loadings on the patellofemoral joint. Sagittal patellar tilt should be considered in the evaluation and management of patellar cartilage defects. Taking sagittal plane malalignment into consideration in patellofemoral joint evaluation will enable us to design new physical and surgical modalities.

Level of evidence

IV.
  相似文献   
1000.
The purpose of this study was to analyze the anatomic and functional results of cartilage tympanoplasty performed on atelectatic ears using the palisade technique and to assess the long-term efficacy of cartilage palisades in preventing recurrent retractions. The records of 54 patients (56 ears) who underwent surgery for atelectasis with or without mastoidectomy from January 2000 to August 2005 were retrospectively evaluated. A successful outcome was defined as complete and intact healing of the graft without perforation, retraction, or lateralization for at least 36 months after the operation, in addition to improvement of hearing indicated by a pure-tone average air-bone gap (PTA-ABG) of less than 20 dB. The mean follow-up period was 44.5 ± 8.0 months (range, 36–68 months). Closure of the tympanic membrane was achieved in 91% of ears. Otomicroscopic evaluation revealed nine (16%) mild and five (8%) moderate retractions, but none of the retractions was deep enough to necessitate tube placement. Postoperative PTA-ABG was less than 20 dB in 71% of ears. The average preoperative and postoperative ABG values, including all types of tympanoplasty operations (Type I, II and III), were 28.4 ± 5.8 and 16.9 ± 6.7 dB, respectively (p < 0.001). No significant difference in the change in PTA-ABG was found between the groups with or without mastoidectomy (p > 0.05). Palisade cartilage tympanoplasty is an effective technique for tympanic membrane closure and hearing improvement in atelectatic ears. Mastoidectomy does not change the anatomic or audiologic findings in these types of ears. We recommend this technique to other otologic surgeons.  相似文献   
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