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31.
Sahin AH 《Journal of pediatric surgery》1999,34(12):1890-1891
32.
Bilen CY Sahin A Ozen H Aki FT Oge O Kendi S 《Journal of endourology / Endourological Society》1999,13(10):751-754
PURPOSE: To define the relation of nonoliguric renal failure to transurethral resection of the prostate (TURP), its clinical importance, and predictive factors. PATIENTS AND METHODS: The files of 439 patients who had undergone TURP at Hacettepe University School of Medicine, Department of Urology, between January 1991 and 1994 were analyzed. The patients were divided into three groups according to postoperative serum creatinine concentration and the presence of clinical signs and symptoms of TUR syndrome (Group I: patients with preoperative and postoperative creatinine in the normal range; Group II: patients suffering nonoliguric renal failure; and Group III: patients with TUR syndrome). The data of the groups were compared in terms of factors influencing nonoliguric renal failure. RESULTS: The mean postoperative concentrations of sodium, blood urea nitrogen, creatinine, and albumin in Groups II and III were statistically different from those in Group I (P < 0.001). There was a moderate relation between hyponatremia and the occurrence of nonoliguric renal failure (r(s) = -0.56). Capsule perforation increased the risk of nonoliguric renal failure 10.6 fold. All of the patients were managed by a conservative approach, and none of the patients died or progressed to end-stage renal disease. They were all discharged with a mean hospitalization period of 7 days and normal renal function tests. CONCLUSION: Nonoliguric renal failure was thought to be an early step in the pathophysiology of TUR syndrome with acute renal failure. It is an asymptomatic clinical picture that is undiagnosed unless laboratory examinations are performed. A conservative therapeutic approach is enough. 相似文献
33.
A G?lgeli C Süer C Ozesmi N Dolu M A?cio?lu O Sahin 《The International journal of neuroscience》1999,99(1-4):69-77
Female/male cognitive differences have been studied for some time; however, such differences in Turkish population is unknown. Evoked potentials (EPs) of the brain have been applied as an index of information processing in a wide variety of normal and cognitive impaired subjects. Scalp event-related potentials (ERP) evoked by auditory stimuli were recorded in 20 male and 18 female neurologically and audiologically normal young Turkish subjects of 18-25 years (Av. 20.6) of age. Standard auditory "Oddball" paradigm involving simple discrimination task of concentrating on infrequent (target) stimulus and ignoring frequent (non-target) stimulus was employed. EEG activity was recorded at the Fz, Cz, Pz and Oz electrode sites of the 10-20 system using Ag/AgCl electrodes. Wave forms were collected and averaged off-line by a Pentium 100 computer, which also controlled the stimulus presentation. In general, significant main effects of gender and electrode site on evoked potential components were found. The interpeak amplitudes N1-P2 and N2-P3 were higher in the male subjects than in the female subjects at Cz. N2-P3 were higher in the male subjects than in the female subjects at Oz. The latencies of N1, P2, N2, P3 components were not different between both sex. For both sexes we found that N1-P2 amplitude was higher at Fz and Cz than Pz and Oz. N2-P3 amplitude was higher at Fz than Oz for only female subject. In male subjects, latency of N2 was longer at Fz than Oz. There were no significant differences in the latencies of N1, P2, and P3 components between electrode sites in both sexes. We suggest that ERP components could be affected by sex, electrode site, and cognitive performance. 相似文献
34.
H A Sahin H G Sahin 《The European journal of contraception & reproductive health care》2003,8(1):11-16
OBJECTIVE: The reasons for not using family planning methods among women aged 15-45 years were investigated in the Eastern region of Turkey. METHODS: A total of 518 randomly selected women were interviewed with a questionnaire. Information was collected on women's fertility behavior and intentions, sources of knowledge and practice of contraception and sociodemographic characteristics. RESULTS: The rate of women who were not using any form of family planning was 45.2%. The reasons for not using any form of family planning were: not having the approval of the husband or family leaders (38%); believing that it was a sin to use a family planning method (32.5%); believing that it could cause abnormal bleeding (14.1%); believing that it could cause infertility (7.3%); believing that it could cause cancer (4.7%); and believing that it could cause pelvic pain (3.4%). CONCLUSION: Efforts should be directed towards education of family members and religious leaders to increase the usage of family planning methods. 相似文献
35.
Estimation of the amniotic fluid volume using the Cavalieri method on ultrasound images. 总被引:5,自引:0,他引:5
B Sahin T Alper A K?k?ü E Malatyalioglu R Kosif 《International journal of gynaecology and obstetrics》2003,82(1):25-30
OBJECTIVES: Presently, a design-based and practical method for measuring amniotic fluid volume (AFV) for routine clinical examinations has not been proposed. In this study we describe a new method, which combines the Cavalieri method with ultrasound imaging to estimate AFV. METHODS: We measured the AFVs of 14 women in the third trimester of pregnancy, and repeated our measurements three times for each woman. Parallel planimetric ultrasonographic images were obtained at every 2 cm along the longitudinal uterine axis. AFVs were calculated as the total of the multiples of the estimated cut surface areas by the section thickness. RESULTS: The mean estimated AFV was 380.5 cm3. The coefficient of error of each measurement was calculated and the mean was 0.108. The coefficient of correlation between the amniotic fluid index and our AFV estimations was 0.87. CONCLUSIONS: Design-based and efficient estimation of AFV is possible with the combination of consecutive ultrasound images and the Cavalieri method. 相似文献
36.
Prognostic significance of tissue transglutaminase in drug resistant and metastatic breast cancer. 总被引:2,自引:0,他引:2
Kapil Mehta Jansina Fok Fred R Miller Dimpy Koul Aysegul A Sahin 《Clinical cancer research》2004,10(23):8068-8076
PURPOSE: Drug resistance and metastasis pose major impediments in the successful treatment of cancer. We previously reported that multidrug-resistant breast cancer cells exhibit high levels of tissue transglutaminase (TG2; EC 2.3.2.13). Because the drug-resistant and metastatic phenotypes are thought to share some common pathways, we sought to determine whether metastatic breast cancer cells express high levels of TG2. EXPERIMENTAL DESIGN: The metastatic breast cancer cell line MDA-MB-231 and the sublines derived from it were tested for TG2 expression. Similarly, several sublines derived from an immortal but normal breast epithelial cell line, MCF10A, representing various stages in breast cancer progression were studied for TG2 expression. The primary and nodal tumor samples from 30 patients with breast cancer were also studied for TG2 expression. RESULTS: The MDA-MB-231 cells expressed high basal levels of TG2. Two clones derived from this cell line, MDA231/cl.9 and MDA231/cl.16, showed a 10- to 15-fold difference in TG2 level. TG2-deficient MDA231/cl.9 cells exhibited higher sensitivity to doxorubicin and were less invasive than were the TG2-sufficient MDA231/cl.16 cells. The MCF10A-derived sublines had increased TG2 expression as they advanced from noninvasive to an invasive phenotype. Importantly, the metastatic lymph node tumors from patients with breast cancer showed significant higher levels of TG2 expression compared with the primary tumors from the same patients. CONCLUSIONS: TG2 expression is up-regulated in drug-resistant and metastatic breast cancer cells, and it can serve as a valuable prognostic marker for these phenotypes. 相似文献
37.
Identification and evaluation of axillary sentinel lymph nodes in patients with breast carcinoma treated with neoadjuvant chemotherapy 总被引:14,自引:0,他引:14
Cohen LF Breslin TM Kuerer HM Ross MI Hunt KK Sahin AA 《The American journal of surgical pathology》2000,24(9):1266-1272
Sentinel lymph node (SLN) biopsy has been shown to predict axillary metastases accurately in early stage breast cancer. Some patients with locally advanced breast cancer receive preoperative (neoadjuvant) chemotherapy, which may alter lymphatic drainage and lymph node structure. In this study, we examined the feasibility and accuracy of SLN mapping in these patients and whether serial sectioning and keratin immunohistochemical (IHC) staining would improve the identification of metastases in lymph nodes with chemotherapy-induced changes. Thirty-eight patients with stage II or III breast cancer treated with neoadjuvant chemotherapy were included. In all patients, SLN biopsy was attempted, and immediately afterward, axillary lymph node dissection was performed. If the result of the SLN biopsy was negative on initial hematoxylin and eosin-stained sections, all axillary nodes were examined with three additional hematoxylin and eosin sections and one keratin IHC stain. SLNs were identified in 31 (82%) of 38 patients. The SLN accurately predicted axillary status in 28 (90%) of 31 patients (three false negatives). On examination of the original hematoxylin and eosin-stained sections, 20 patients were found to have tumor-free SLNs. With the additional sections, 4 (20%) of these 20 patients were found to have occult lymph node metastases. These metastatic foci were seen on the hematoxylin and eosin staining and keratin IHC staining. Our findings indicate that lymph node mapping in patients with breast cancer treated with neoadjuvant chemotherapy can identify the SLN, and SLN biopsy in this group accurately predicts axillary nodal status in most patients. Furthermore, serial sectioning and IHC staining aid in the identification of occult micrometastases in lymph nodes with chemotherapy-induced changes. 相似文献
38.
BACKGROUND: Antiapoptotic signals are important in the development, progression and prognosis of malignant tumors. The aim of this study was to determine the two distinct antiapoptotic signals-survivin and aven-in acute leukemias and compare them with clinical and hematological findings and response to therapy. Real-time quantitative PCR was used and survivin and aven were detected at the messenger (m)RNA level. PATIENTS AND METHODS: Sixty-five patients with acute leukemia [37 with acute myeloblastic leukemia (AML) and 28 with acute lymphoblastic leukemia (ALL)] were used as the study group and 10 healthy subjects were used as the control group. RESULTS: Survivin was between 0.0 and 0.829 copy number/cell (median 0.0721, mean 0.5424301909 +/- 0.139799488589) and aven was between 0.0 and 0.853 copy number/cell (median 0.0124, mean 0.070335542 +/- 0.1524685709). We found an important association between survivin and aven (P = 0.000). Both survivin and aven were higher in the study group than in the controls (P = 0.001 and 0.035, respectively). When we compared survivin and aven with other clinical and hematological parameters, there was an important association between survivin and extramedullary involvement (P = 0.033), survivin and alkaline phosphatase (P = 0.06), white blood cell (WBC) count and lactate dehydrogenase (LDH) (P = 0.000), WBC count and uric acid (P = 0.074), hemoglobin level and LDH (P = 0.072), LDH and uric acid (P = 0.057), CD7 expression and survivin (P = 0.097), and CD34 expression and aven (P = 0.058). Response to therapy was evaluated according to the survivin and aven levels. Survivin level was lower in refractory patients as compared with complete responders (P = 0.085). Aven level was higher in patients with relapse as compared with non-relapse patients (P = 0.04). There was no important association between survivin or aven and performance status, lymphadenopathy or organomegaly. CONCLUSIONS: Both survivin and aven are important antiapoptotic signals in acute leukemias, and the association between extramedullary involvement, CD7 expression and CD34 expression, which are important poor prognostic indicators in acute leukemias, suggests that survivin and/or aven may be novel prognostic indicators in acute leukemias. Further studies with a higher number of patients will be more informative. 相似文献
39.
Methylation of cyclin D2 is observed frequently in pancreatic cancer but is also an age-related phenomenon in gastrointestinal tissues. 总被引:5,自引:0,他引:5
40.
Angiogenesis in Vulvar Intraepithelial Neoplasia 总被引:1,自引:0,他引:1
Dagmar Bancher-Todesca M.D. Andreas Obermair M.D. Selcuk Bilgi M.D. Petra Kohlberger M.D. Christian Kainz M.D. Gerhard Breitenecker M.D. Sepp Leodolter M.D. Gerald Gitsch M.D. 《Gynecologic oncology》1997,64(3):496-500
Vulvar intraepithelial neoplasia (VIN) has been reported to be a precursor of invasive vulvar cancer. Switching to the angiogenic phenotype is considered a key step in tumor growth. Microvessel density (MVD) and vascular endothelial growth factor (VEGF), a highly angiogenic peptide, are important parameters of tumor angiogenesis. Forty-three histologic slides with 38 VIN I–III lesions were immunohistochemically stained for factor VIII-related antigen (F8-RA) and 44 slides with 37 VIN I–III for VEGF, since F8-RA reliably highlights tumor microvessels. Determination of MVD and VEGF expression was done by counting microvessels and VEGF-positive cells at a magnification of 200× and 400×. The highest concentration of F8-RA-stained MVD and VEGF expression was found at a small subepithelial area at the border of the VIN lesion to the stroma underneath but concentrations were low in all specimens of normal epithelium. High VEGF expression was significantly correlated to high MVD. For both MVD and VEGF expression the differences between VIN I and VIN III and between VIN II and VIN III were statistically significant (P< 0.0001). VIN III lesions are the clinical relevant precursors of invasive cancer of the vulva, as outlined by intense expression of VEGF protein and a highly dense network of microvessels underlying the dysplastic epithelium. 相似文献