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81.
This study investigated the effect of rifampin on the thickness of capsules around silicone implants by bactericidal activity
against Stapylococcus epidermidis. Silicone blocks (1 × 1 cm) were placed into pockets created for each of the 40 rats included in the study. In group 1, the
operation was performed under aseptic conditions. In group 2, standard S. epidermidis was inoculated into the pocket, whereas rifampin and S. epidermidis were applied in group 3. In group 4, only rifampin was applied topically on implants. After 12 weeks, the peri-implant capsules
were removed and examined under a photomicroscope and a scanning electron microscope. The mean thickness of the capsules was
63.307 μm in group 1, 111.538 μm in group 2, 43.076 μm in group 3, and 30.384 μm in group 4. The differences between groups
2 and 3 and groups 2 and 4 were found to be statistically significant (p < 0.001). Rifampin appears to be an agent for preventing peri-implant capsule formation. 相似文献
82.
PURPOSE: We previously demonstrated that assessment of the number of positive cores, tumor length in a core, Gleason score and prostate volume significantly enhanced the accuracy of a prediction model for low volume/low grade cancer in men who had undergone extended biopsy. To determine the validity of the model, we applied it to an independent population of men with prostate cancer. MATERIALS AND METHODS: The study group included 170 men who had undergone radical prostatectomy without neoadjuvant therapy. In all cases, prostate cancer was diagnosed on only 1 positive core of a 10-core extended biopsy. We assessed the accuracy of the model, which consists of tumor length less than 2 mm, Gleason score 3+4 or less and prostate gland volume greater than 50 cc in predicting the occurrence of low volume/low grade cancer (defined as tumor volume less than 0.5 cc, no Gleason grade 4 or 5 disease, and organ confined disease). RESULTS: Of the patients 101 (59.4%) had low volume/low grade cancer. Our model using all 3 previously mentioned variables had the highest performance, demonstrating a positive predictive value of 70.4% (88 of 125), a negative predictive value of 71.1% (32 of 45) and a diagnostic accuracy of 70.6% (120 of 170). This model performed better than a model based on tumor length only (positive predictive value, negative predictive value and diagnostic accuracy 68.1%, 57.9% and 64.7%, respectively) or a model based on tumor length and Gleason score (positive predictive value, negative predictive value and diagnostic accuracy 70.0%, 60.0% and 66.5%, respectively). CONCLUSIONS: This study validates that our model with a combination of tumor length, Gleason score and prostate volume is predictive for low volume/low grade cancer in an independent population of men who demonstrated only 1 positive core in an extended biopsy. This model can be used as a tool for selecting men for active surveillance. 相似文献
83.
Eskicorapci SY Guliyev F Islamoglu E Ergen A Ozen H 《International urology and nephrology》2007,39(1):189-195
OBJECTIVES: To evaluate the diagnostic performance of 14-core repeat biopsy protocol and the impact of prior biopsy scheme on repeat prostate biopsy group. METHODS: 211 patients had repeat biopsy using 14-core protocol consisting of 10-core peripheral zone (classical sextant+4 lateral peripheral cores) and 4-core transitional zone (TZ) biopsies. The diagnostic yield was determined both in patients who had previously undergone sextant or 10-core biopsy protocol. RESULTS: Overall cancer detection rate was 25.6%. 14-core biopsy technique detected cancer in 36.1 and 18.7% of the patients who had a previous sextant biopsy and 10-core biopsy protocol, respectively (P = 0.005). Patients with and without high-grade prostatic intraepithelial neoplasia (HGPIN) in the previous sextant biopsy had 56.5 and 28.3% cancer detection rates on the subsequent extended biopsy, respectively (P = 0.017) Patients who had previous 10-core biopsy with and without HGPIN revealed 22.9 and 17.2% cancer detection rates, respectively (P = 0.465) Additional four lateral peripheral cores detected 33% (3/30) and 17% (4/24) of cancers in patients with previous sextant and 10-core biopsy, respectively. 3.7% of the patients had tumor only in the TZ and none of them had prior extended biopsy. CONCLUSIONS: The yield of extended 14-core repeat biopsy protocol was higher in patients with previous negative sextant biopsy compared to the patients with previous negative 10-core biopsy. HGPIN history found on previous sextant biopsy was a strong cancer predictor on repeat biopsy; same was not true for the patients with previous 10-core biopsy. The yield of lateral peripheral cores and TZ biopsies were lower in patients with prior negative extended biopsy. 相似文献
84.
Savas N Ocal S Colak T Karakayali H Yilmaz U Haberal M 《Transplantation proceedings》2007,39(4):984-986
Patients with end-stage renal disease are at high risk for exposure to hepatitis C virus (HCV) infection. Although both viral replication and liver disease progression are accelerated after renal transplantation, the long-term impact of chronic HCV infection is unclear. Our aim was to analyze the course of HCV infection in renal transplant recipients and the effects of HCV reactivation on patient and graft survival. METHODS: We retrospectively examined the 21-year (1985-2006) data of 1274 renal transplant recipients, 43 of whom were anti-HCV positive at the time of transplantation. RESULTS: The mean posttransplant follow-up of 43 patients was 62.0 +/- 7.3 months. At the time of transplantation, HCV RNA was positive in 11 (25.6%) patients and negative in 32 (74.4%) patients. HCV reactivation was seen in 19 (45.2%) patients at a mean time of 20.8 +/- 5.7 months. In 31 (72%) patients, acute rejection occurred, whereas graft loss occurred in 10 (23%) patients. Three (7%) patients died. Among 43 patients, 22 (51.2%) were treated with interferon before transplantation. There was a statistically significant association between pretransplant interferon therapy and pretransplant HCVRNA level (P=.024), but no significant association of HCV reactivation and graft rejection, mortality, or kidney survival. CONCLUSION: HCV reactivation occurred in nearly half of the renal transplant recipients, mostly in the second year. Patient survival and graft survival were not affected by HCV reactivation. Anti-HCV positivity should not preclude chronic renal failure patients from renal transplantation. 相似文献
85.
It has not clearly been defined in the literature which side of the pedicled LIMA graft should be anastomosed to the posterior coronary arteries. Using the ventral side of pedicled LIMA graft causes an 180 degree torsion of the pedicle. Sometimes this torsion may cause reduction or cessation of LIMA flow as we have seen in two of our patients. In this paper we point out that using the dorsal side of the pedicled LIMA graft for anastomosis to the posterior coronary arteries is helpful. 相似文献
86.
OBJECTIVE: Total correction of classical tetralogy of Fallot (TOF) by transatrial approach has become a standard procedure in the goal to minimize structural damage to the pulmonary pump. The most critical point in transatrial repair of TOF is infundibular dissection. Right atrial approach provides better surgical exposure for parietal extension of the infundibular septum when compared to the right ventricular approach. However it is not always easy to determine the localization and amount of muscle bundles to be resected and this surgical maneuver requires experience. METHODS: Nineteen patients who had repair of isolated TOF using this technique from 1993 to 2001 were reviewed. The mean age of patients were 5 +/- 2 years. Transatrial-transpulmonary approach were performed for all patients. To make easier the infundibular muscle bundles resection and to determine the localization and amount of muscle bundle to be resected, we placed a Hegar dilator into the right ventricle through pulmonary arteriotomy. The muscle bundles between the dilator and the anterior leaflet annulus of the tricuspid valve were totally excised until the intraventricular part of the dilator and pulmonary annulus became completely visible. The area between the Hegar dilator and the margins of the ventricular septal defect (VSD) was left untouched. None of the patients had transannular patch. To improve exposure, tricuspid valve detachment was performed in 11 patients. All patients were followed-up in our clinic every 6 months using echocardiography. RESULTS: There were no early or late deaths, and no reoperation for residual VSD or residual right ventricle (RV) outflow obstruction. All patients were in NYHA Class I. RV on the echocardiography was spared late dilatation and had a good late functional status. Eighteen patients had no or mild pulmonary regurgitation. One patient who had undergone tricuspid anterior leaflet detachment showed mild tricuspid insufficiency. CONCLUSION: On the basis of hemodynamic outcomes, this procedure for elective repair of TOF in selected cases shows excellent early and mid-term results. 相似文献
87.
Yuksel E Ozer E Kizildag S Sercan O Canda T Sakizli M 《Breast (Edinburgh, Scotland)》2002,11(6):473-477
Microsatellite instability (MSI) is a form of genomic instability associated with defective DNA mismatch repair in tumors. MSI is found in 85-90% of hereditary nonpolyposis colorectal cancer cases; however, its occurrence in breast carcinogenesis still remains to be clarified. In addition, data are limited on the incidence of MSI in the medullary subtype. The purpose of this study was to investigate the occurrence of MSI in medullary breast cancer (MBC). The study included a total of 16 patients with MBC, nine with typical and seven with atypical histology. The incidence of MSI in five microsatellite loci (D2S123, D3S1611, D17S807, D17S796 and Xq11-12) was determined by comparing paired normal and tumor tissue DNA after PCR amplification from paraffin-embedded tissues. All 16 tumors showed stability at five loci. Although the number of microsatellite markers and DNA samples may limit the value of our results, we conclude that the MSI phenotype is uncommon in human MBC. 相似文献
88.
Neriman Sila Koc Rahmi Yilmaz Tolga Yildirim Gonca Eldem Bora Peynircioglu Yunus Erdem 《Transplantation proceedings》2021,53(3):1010-1013
Secondary hyperparathyroidism is one of the most common complications of chronic kidney failure. If prolonged, parathyroid hormone release gains autonomy and tertiary hyperparathyroidism with parathyroid adenoma or hyperplasia can be develop. Tertiary hyperparathyroidism is associated with increased risk of mortality and morbidity; thus, treatment is recommended. Medical treatment includes phosphate binders, vitamin D analogues, and calcimimetic agents. Most cases of tertiary hyperparathyroidism can be controlled with medical treatment. When medical treatment options prove insufficient, parathyroidectomy is recommended. However, recurrence after parathyroidectomy is possible, which requires an alternative treatment. We present our percutaneous embolization experience, which has not been tried in the treatment of tertiary hyperparathyroidism in renal transplantation patients diagnosed with tertiary hyperparathyroidism. 相似文献
89.
BACKGROUND: Autonomic neuropathy is an important cause of morbidity and mortality in patients with chronic renal failure (CRF) on hemodialysis. Generally, cardiovascular reflex tests are used to determine autonomic neuropathy. Our purpose in this study was to determine the frequency of autonomic neuropathy in patients with CRF on hemodialysis by using cardiovascular reflex tests and compare the sensitivity of each test. METHODS: The authors performed five tests: heart rate response to the Valsalva maneuver, heart rate variation during deep breathing, heart rate response to standing up, blood pressure response to standing up, and blood pressure response to hand grip exercise in order to determine autonomic neuropathy. Each test subject was evaluated as normal, borderline, and abnormal and scored as 0, 1, and 2, respectively. Subjects with a total score > or = 5 were considered to have autonomic neuropathy. Forty subjects with CRF on hemodialysis were included in this study. None of the subjects had diabetes mellitus or any other etiology that could cause autonomic neuropathy. RESULTS: Thirty-five of 40 subjects (87.5%) had abnormal autonomic tests. In 35 subjects, the relationship between autonomic neuropathy and biochemical parameters, effects of treatment with vitamin D and erythropoietin, and urea reduction rate were studied. No relationship was found between autonomic neuropathy and age, time on hemodialysis, urea reduction rate, albumin, ferritin, calcium, inorganic phosphorus, intact parathyroid hormone, hemoglobin levels, and treatment with vitamin D and erythropoietin. The abnormal test results were as follows: 20 subjects (50%) in the heart rate response to the Valsalva Maneuver, 31 (77.5%) in the heart rate variation during deep breathing, 28 (70%) in the heart rate response to standing up, 6 (15%) in the blood pressure response to standing up, and 31 subjects (77.5%) in the blood pressure response to hand grip exercise tests. Among these five tests, the two most abnormal tests were the heart rate variation during deep breathing and the blood pressure response to hand grip exercise. CONCLUSION: Patients with CRF on hemodialysis frequently have autonomic neuropathy. For the diagnosis and follow-up of patients, five cardiovascular autonomic reflex tests are generally used. In this study, it was determined that performing only one test instead of all five tests has a high sensitivity and is more practicable in terms of determining autonomic neuropathy. 相似文献
90.
Treatment of humeral shaft non-unions by the Ilizarov method 总被引:3,自引:1,他引:3
Thirty-five humeral shaft non-unions treated by the Ilizarov external fixator were studied after an average of 39 months. Bone union was achieved in all but one. The mean time to union was 5.5 months (range: 3-10 months). Major pin tract problems leading to removal of the Schanz screws occurred in three patients. A radial nerve palsy developed in three patients, two recovered spontaneously and one was treated with a triple tendon transfer. 相似文献