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排序方式: 共有3813条查询结果,搜索用时 31 毫秒
31.
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
32.
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
33.
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
34.
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
35.
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
36.
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
37.
Ismail Koramaz Mehmet Ozkan Murat Kesim Kibar Yasar Güven Mine Kadioglu Cunay Ulku Umit Cobanoglu Ersin Yaris Nuri Ihsan Kalyoncu Fahri Ozcan 《Pharmacological research》2005,51(6):567-573
Perioperative spasm of internal mammary artery is a common experience in coronary artery bypass grafting. Many techniques were described of harvesting the internal mammary artery to prevent vasospasm. We investigated the comparison of the contracting and relaxing responses of human internal mammary artery grafts harvested by two different methods. Patients were divided into two groups depending on the harvesting technique. In the first and second groups arteries were harvested by classical and carbon dioxide insufflation techniques, respectively. In both groups, endothelial function of arteries was assessed by precontracting the rings with phenylephrine (10(-5)M) and dilatating them by cumulative acetylcholine (10(-8) to 10(-5)M) concentrations. Cumulative concentration-response curves for phenylephrine (10(-8) to 10(-4)M), noradrenaline (10(-9) to 10(-4)M), and 5-hydroxytryptamine (10(-9) to 10(-4)M) were obtained in all groups. Endothelial integrity of arteries were histopathologically evaluated. In both groups, acetylcholine caused concentration-dependent relaxations in rings precontracted with phenylephrine (10(-5)M). In arteries harvested by carbon dioxide insufflation technique, acetylcholine caused significantly higher relaxations compared to the rings obtained by classical technique (p<0.05). In all rings of study groups, phenylephrine, noradrenaline and 5-hydroxytryptamine caused concentration-dependent contractions. There was not any significant difference in concentration-dependent responses of these contracting pharmacological agents between the groups. Histopathological evaluation revealed no major arterial damage in both groups. Carbon dioxide insufflation technique does seem not only to protect the integrity of the endothelium and the whole vessel, but also prevent the possible vasospasm of the internal mammary artery segments. 相似文献
38.
Percutaneous nephrolithotomy in older children 总被引:4,自引:0,他引:4
Sahin A Tekgül S Erdem E Ekici S Hasçiçek M Kendi S 《Journal of pediatric surgery》2000,35(9):1336-1338
PURPOSE: The aim of this study was to evaluate the safety and efficacy of percutaneous nephrolithotomy (PCNL) in pediatric patients, older than 8 years, without any technical and instrumental modifications. METHODS: The authors retrospectively evaluated the data of 16 percutaneously treated kidneys of 14 patients with a mean age of 11 years (range, 8 to 17). The mean stone burden was calculated as 301 mm2 (range, 120-750). Percutaneous accesses were done under fluoroscopic control, and 24F to 30F Amplatz dilators were used depending on patient size. Ultrasonic and laser lithotripsy were performed to fragment calculi. RESULTS: Mean operating time was 111 minutes (range, 60 to 210 min) and no intraoperative or postoperative major complication was observed. Mean hemoglobin drop after the procedure was 1.16 g/dL (range, 0.3 to 2.8). Blood transfusion was required in only 1 patient, and mean postoperative hospitalization was 4.6 days (range, 3 to 10). Stone-free rate was calculated as 69% (11 of 16), but with residual fragments smaller than 4 mm, the success rate becomes 100% at patient's discharge. CONCLUSIONS: PCNL is an effective and safe form of therapy in pediatric stone disease. Especially in older children the use of the same instruments and technique as in adults may achieve equal results without any increased risk of possible morbidity and need of blood transfusion. 相似文献
39.
I Sahin R Serter F Karakurt B Demirbas C Culha C Taskapan F Kosar Y Aral 《Gynecological endocrinology》2004,19(3):115-124
In addition to the reproductive consequences, polycystic ovary syndrome (PCOS) is characterized by a metabolic disorder in which hyperinsulinemia and insulin resistance are central features. The effects and possible benefits from insulin-sensitizing drugs are not well known, especially in non-obese women with PCOS. This study was designed to evaluate the effects of metformin and flutamide on metabolic parameters and insulin resistance in non-obese women with PCOS. Thirty non-obese women newly diagnosed with PCOS and 15 age- and weight-matched healthy volunteers as controls were included in the study. Patients were assigned randomly to receive flutamide 250 mg daily or metformin 850 mg three times daily. Glucose, insulin, insulin resistance, androgen levels and glucose and insulin responses to an oral glucose tolerance tests (OGTT) were assessed before and after a 4-week therapy period. A positive correlation was found between body mass index and insulin level in patients with PCOS and controls. Follicle stimulating hormone, luteinizing hormone, free testosterone and dehydroepiandrosterone sulfate levels decreased significantly, but insulin resistance levels were not changed after flutamide therapy. Body weight, free testosterone, insulin and insulin resistance levels decreased significantly after metformin therapy. In conclusion, metformin treatment improved insulin sensitivity and decreased androgen levels, and flutamide decreased androgen levels but failed to improve insulin sensitivity in the non-obese women with PCOS. 相似文献
40.
Aman U Buzdar Nuhad K Ibrahim Deborah Francis Daniel J Booser Eva S Thomas Richard L Theriault Lajos Pusztai Marjorie C Green Banu K Arun Sharon H Giordano Massimo Cristofanilli Debra K Frye Terry L Smith Kelly K Hunt Sonja E Singletary Aysegul A Sahin Michael S Ewer Thomas A Buchholz Donald Berry Gabriel N Hortobagyi 《Journal of clinical oncology》2005,23(16):3676-3685
PURPOSE: The objective of this study was to determine whether the addition of trastuzumab to chemotherapy in the neoadjuvant setting could increase pathologic complete response (pCR) rate in patients with human epidermal growth factor receptor 2 (HER2) -positive disease. PATIENTS AND METHODS: Forty-two patients with HER2-positive disease with operable breast cancer were randomly assigned to either four cycles of paclitaxel followed by four cycles of fluorouracil, epirubicin, and cyclophosphamide or to the same chemotherapy with simultaneous weekly trastuzumab for 24 weeks. The primary objective was to demonstrate a 20% improvement in pCR (assumed 21% to 41%) with the addition of trastuzumab to chemotherapy. The planned sample size was 164 patients. RESULTS: Prognostic factors were similar in the two groups. After 34 patients had completed therapy, the trial's Data Monitoring Committee stopped the trial because of superiority of trastuzumab plus chemotherapy. pCR rates were 25% and 66.7% for chemotherapy (n = 16) and trastuzumab plus chemotherapy (n = 18), respectively (P = .02). The decision was based on the calculation that, if study continued to 164 patients, there was a 95% probability that trastuzumab plus chemotherapy would be superior. Of the 42 randomized patients, 26% in the chemotherapy arm achieved pCR compared with 65.2% in the trastuzumab plus chemotherapy arm (P = .016). The safety of this approach is not established, although no clinical congestive heart failure was observed. A more than 10% decrease in the cardiac ejection fraction was observed in five and seven patients in the chemotherapy and trastuzumab plus chemotherapy arms, respectively. CONCLUSION: Despite the small sample size, these data indicate that adding trastuzumab to chemotherapy, as used in this trial, significantly increased pCR without clinical congestive heart failure. 相似文献