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151.
Besides suppressing sebum production, the exact mechanism of action of isotretinoin in acne vulgaris is not known. Several hormones have been linked to the pathogenesis of acne. In this study, we investigated the effects of isotretinoin on the pituitary-adrenal axis, whose activity may be increased in acne. Various hormone systems were evaluated before and after 3 months of isotretinoin treatment in 47 acne patients. Free triiodothyronine (T3), thyroid-stimulating hormone and thyroid-stimulating hormone receptor antibody levels decreased significantly during isotretinoin treatment (p?0.001, p?0.02 and p?0.02, respectively), as did those of luteinising hormone, prolactin and total testosterone (p?0.005), as well as morning cortisol and adrenocorticotropic hormone (p?0.005 and p?0.05, respectively). We conclude that isotretinoin causes mild suppression of pituitary hormone levels, which may be beneficial for tackling the pathogenesis of acne. 相似文献
152.
Isotretinoin is an effective therapy for severe nodulocystic acne. Several experimental studies suggest that it may have an effect on vitamin D physiology. In the present study, the authors aimed to investigate the effect of isotretinoin treatment on the metabolism of vitamin D in acne patients. A prospective analysis of 50 consecutive acne patients who were treated with isotretinoin for 3 months was done. Before and after 3 months of treatment, 25 hydroxy vitamin D, 1,25 dihydroxy vitamin D, and bone alkaline phosphatase, calcium, phosphate, and parathormone levels were measured. The 25 hydroxy vitamin D and serum calcium levels decreased significantly (p < 0.0001, p < 0.05, respectively), whereas 1,25 dihydroxy vitamin D, parathormone, and bone alkaline phosphatase levels increased significantly after 3 months of isotretinoin treatment (p < 0.005, p < 0.005, p < 0.0001, respectively). Aspartate aminotransferase, total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels also increased significantly after isotretinoin treatment. This prospective clinical study showed that isotretinoin has an effect on vitamin D metabolism. Further clinical studies with longer periods of follow-up are needed to understand the effect of isotretinoin on vitamin D and bone metabolism. 相似文献
153.
Accuracy of frozen sections for intraoperative diagnosis of complex atypical endometrial hyperplasia
Turan T Karadag B Karabuk E Tulunay G Ozgul N Gultekin M Boran N Isikdogan Z Kose MF 《Asian Pacific journal of cancer prevention》2012,13(5):1953-1956
Objective: The purpose of this study was to correlate the histological diagnosis made during intraoperativefrozen section (FS) examination of hysterectomy samples with complex atypical endometrial hyperplasia (CAEH)diagnosed with definitive paraffin block histology. Methods: FS pathology results of 125 patients with a preoperativebiopsy showing CAEH were compared retrospectively with paraffin block pathology findings. Results:Paraffin block results were consistent with FS in 78 of 125 patients (62.4%). The FS sensitivity and specificityof detecting cancer were 81.1% and 97.9%, with negative and positive predictive values of 76.7%, and 98.4%,respectively. Paraffin block results were reported as endometrial cancer in 77 of 125 (61.6%) patients. Finalpathology was endometrial cancer in 45.3% patients diagnosed at our center and 76.9% for patients who hadtheir diagnosis at other clinics (p=0.018). Paraffin block results were consistent with FS in 62.4% of all casesConsistence was 98.4% in patients who had endometrial cancer in FS. Conclusion: FS does not exclude thepossibility of endometrial cancer in patients with the preoperative diagnosis of CAEH. In addition, sufficientendometrial sampling is important for an accurate diagnosis 相似文献
154.
Man Fai Law Rita Ho Carmen KM Cheung Lydia HP Tam Karen Ma Kent CY So Bonaventure Ip Jacqueline So Jennifer Lai Joyce Ng Tommy HC Tam 《World journal of gastroenterology : WJG》2016,22(28):6484-6500
Hepatitis due to hepatitis B virus(HBV) reactivation can be severe and potentially fatal, but is preventable. HBV reactivation is most commonly reported in patients receiving cancer chemotherapy, especially rituximabcontaining therapy for hematological malignancies and those receiving stem cell transplantation. All patients with hematological malignancies receiving anticancer therapy should be screened for active or resolved HBV infection by blood tests for hepatitis B surface antigen(HBs Ag) and antibody to hepatitis B core antigen(antiHBc). Patients found to be positive for HBs Ag should be given prophylactic antiviral therapy to prevent HBV reactivation. For patients with resolved HBV infection, no standard strategy has yet been established to prevent HBV reactivation. There are usually two options. One is pre-emptive therapy guided by serial HBV DNA monitoring, whereby antiviral therapy is given as soon as HBV DNA becomes detectable. However, there is little evidence regarding the optimal interval and period of monitoring. An alternative approach is prophylactic antiviral therapy, especially for patients receiving highrisk therapy such as rituximab, newer generation of anti-CD20 monoclonal antibody, obinutuzumab or hematopoietic stem cell transplantation. This strategy may effectively prevent HBV reactivation and avoid the inconvenience of repeated HBV DNA monitoring. Entecavir or tenofovir are preferred over lamivudine as prophylactic therapy. Although there is no well-defined guideline on the optimal duration of prophylactic therapy, there is growing evidence to recommend continuing prophylactic antiviral therapy for at least 12 mo after cessation of chemotherapy, and even longer for those who receive rituximab or who had high serum HBV DNA levels before the start of immunosuppressive therapy. Many novel agents have recently become available for the treatment of hematological malignancies, and these agents may be associated with HBV reactivation. Although there is currently limited evidence to guide the optimal preventive measures, we recommend antiviral prophylaxis in HBs Ag-positive patients receiving novel treatments, especially the Bruton tyrosine kinase inhibitors and the phosphatidylinositol 3-kinase inhibitors, which are B-cell receptor signaling modulators and reduce proliferation of malignant B-cells. Further studies are needed to clarify the risk of HBV reactivation with these agents and the best prophylactic strategy in the era of targeted therapy for hematological malignancies. 相似文献
155.
156.
Karadag LS Bala O Türköz E Mihçioğlu T 《The journal of contemporary dental practice》2004,5(2):93-101
In this study, the aim was to assess the in vitro apical microleakage of a resin-based sealer used with two different adhesives. Thirty nine freshly extracted maxillary incisors were used. The teeth were decoronated at the cemento-enamel junction with a water-cooled fissure bur. Chemo-mechanical debridement of the root canals was accomplished with the step-back technique. The smear layer was removed by 19% ethylenediamine tetra acetic acid (EDTA). The roots were then divided into three experimental groups of thirteen teeth in each. Specimens in group 1 were filled with gutta-percha, AH Plus sealer, and water-based adhesive system (Syntac Single Component). Group 2 specimens were filled with gutta-percha, AH Plus sealer, and acetone-based dentin adhesive (Prime & Bond NT ). Specimens of group 3 were filled with only gutta-percha and AH Plus sealer (no adhesive was applied). The teeth were immersed into 2% methylene blue solution. Apical sealing qualities were assessed by measuring the linear dye penetration with a stereomicroscope. Dentin tubule penetration was observed under scanning electron microscopy (SEM). Results showed no statistically significant difference between the materials used, however, the leakage in group 2 was less than group 1 and 3. 相似文献
157.
目的在甲状腺手术中缺少术中神经监测(intra operative neuromonitoring,IONM)的标准化操作可导致结果变异性强,这些结果可产生错误信息并增加喉返神经损伤的危险性。因此有必要进行IONM操作的标准化。方法本研究共招募了289例进行过甲状腺切除术的患者(435根神经有危险),均由一位外科医师实施手术。每例患者均由同一位麻醉师使用EMG气管导管进行插管。每例患者均进行标准化IONM操作。该操作包括术前和术后对声带运动进行录像监测、保证电极在正确位置、喉返神经剥离前后刺激迷走神经并记录EMG信号,并摄像记录暴露的喉返神经。结果5例患者出现IONM波形异常,是由于电极错位所致,这一问题被立刻监测到。监测到1例患者在手术较早阶段出现非喉返神经损伤。甲状腺剥离时18例患者的神经失去了EMG信号,使用我们的标准化IONM操作后神经损伤的原因得以清楚阐明。结论标准化IONM操作不仅在消除错误的IONM结果方面有用且有帮助,而且有助于阐明喉返神经损伤的机制。在确定外科手术的缺陷并提高外科手术技巧后,本研究显著降低了神经麻痹的发生率。 相似文献
158.
Turan T Hizli D Sarici S Boran N Gundogdu B Karadag B Tulunay G Kose MF 《European journal of obstetrics, gynecology, and reproductive biology》2011,158(2):274-279
Objective
The purpose of this study was to determine the histopathologic risk factors for pelvic lymph node (PLN) and para-aortic lymph node (PALN) metastasis in endometrial cancer (EC) and to identify in which patients PALN dissection should be performed.Study design
A total of 204 consecutive patients, with EC and underwent systematic pelvic and para-aortic lymphadenectomy extending to the renal vessels, were studied retrospectively. Statistical significance between risk factors was examined using multivariant logistic regression analysis.Results
Cell type, depth of myometrial invasion and tumor size were found to be independently related to PLN metastasis. PLN metastasis in any site and lymphovascular invasion (LVSI) were independent prognostic factors for predicting PALN metastasis. The sensitivity, specificity and the NPV of PLN metastasis for detecting PALN metastasis were 80.8%, 89.3% and 97%, respectively. Furthermore, the 204 patients were divided into two groups according to the presence of one of these following factors: (1) non-endometrioid cell type, (2) PLN metastasis, (3) LVSI, (4) adnexal metastasis and (5) serosal involvement. Among these 204 patients, 104 had one or more of these factors (group A), and 100 patients had none of these factors (group B). PALN metastasis was significantly greater in group A, compared to group B. The sensitivity and the NPV of these combined prognostic factors for predicting PALN metastasis were 96.2% and 99%, respectively.Conclusions
Presence of non-endometrioid cell type, PLN metastasis, LVSI, adnexal metastasis or serosal involvement diagnosed by frozen section (FS) seem to be poor prognostic factor for PALN metastasis in EC. Also, PALN dissection should be extended to the level of the renal vessels in all patients who will undergo PALN dissection, due to frequent involvement of the supramesenterial region. 相似文献159.
Tokatli F Uzal C Doganay L Kocak Z Kaya M Ture M Kurum T Alkaya F Karadag H Kutlu K 《International journal of radiation oncology, biology, physics》2004,58(4):1228-1234
PURPOSE: The aim of this study is to determine the cardioprotective efficacy of amifostine. The study consists of researching the relationship between plasma brain natriuretic peptide levels and the electrical and morphologic changes in irradiated rats with or without amifostine. METHODS AND MATERIALS: Sixty Wistar albino rats were divided into 4 groups, and their hearts were given 15 Gy/fraction with (60)Co. In Groups I and II, the rats were killed after 24 hours to detect early effects; in Groups III and IV, the rats were killed 100 days after irradiation to detect late effects. Before irradiation, Groups I and III received 0.9% saline solution, whereas Groups II and IV received amifostine (200 mg/kg). Twenty rats were used as a control group. RESULTS: On the 100th day, mild myocardial degeneration was detected in 5 rats (33%) from Group III (no amifostine). This percentage was statistically different from that of Group IV (treated with amifostine) and the controls (p = 0.042). There was no statistically significant difference between the mean plasma brain natriuretic peptide values of the groups (p > 0.05). There was no significant difference in electrocardiographies between the groups. There was no correlation between continuous variables. CONCLUSION: In the amifostine group (IV) on the 100th day, there was no myocardial degeneration, suggesting that amifostine has a cardioprotective effect. 相似文献
160.