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731.
Aydin K Ciftci K Terzibasioglu E Ozkan M Demirtas A Sencer S Minareci O 《AJNR. American journal of neuroradiology》2005,26(1):128-136
BACKGROUND AND PURPOSE: Brain has a capacity for reorganization that enables use-dependent adaptations to acquire skills. Previous studies demonstrated morphometric and functional use-dependent changes in the brains of musicians. The purpose of this study was to investigate the differences in metabolite concentrations in the planum temporale, an area strongly associated with the processing of music perception, between trained musicians and non-musicians. We hypothesized that the microscopic changes leading to use-dependent adaptations in brain might cause neurometabolite changes that could be detected with quantitative proton MR spectroscopy. METHODS: We performed quantitative proton MR spectroscopy in the left planum temporale of 10 musicians (six men and four women; age range, 20-37 years) and in those of 10 age- and sex-matched control subjects who had no musical training. We calculated the major metabolite concentrations in the left planum temporale. RESULTS: The difference in N-acetylaspartate (NAA) concentrations between the musicians and the non-musician control subjects was statistically significant (P <.01). No significant difference was noted in the choline and creatine concentrations between the musicians and the non-musician control subjects (P >.05). The NAA concentration of the musicians correlated with the total duration of musical training and activity (r=0.733, P <.05). CONCLUSION: Long-term, professional musical activity caused significant changes in the neurometabolite concentrations that might reflect the physiologic mechanism(s) of use-dependent adaptation in the brains of musicians. 相似文献
732.
Zeyneloglu P Donmez A Bilezikci B Mercan S 《Journal of cardiothoracic and vascular anesthesia》2005,19(3):329-333
OBJECTIVE: Corrective surgery for congenital heart defects in children frequently requires cardiopulmonary bypass (CPB). Serum and bronchoalveolar levels of interleukin-6 (IL-6) may be useful in assessing the severity of the systemic inflammatory response after CPB. In the present study, the authors aimed to compare the effects of ketamine anesthesia and isoflurane anesthesia with respect to serum and tracheobronchial aspirate (TBA) IL-6 levels in infants undergoing CPB for cardiac surgery. DESIGN: Prospective and randomized controlled study. SETTING: University-based teaching hospital. PARTICIPANTS: Thirty-four infants aged 2 to 24 months were randomized into 2 groups. INTERVENTIONS: In group K (n = 17), anesthesia was induced with intravenous (IV) ketamine, 1 to 2 mg/kg, and fentanyl, 1 to 2 microg/kg, and was maintained with infusions of ketamine, 25 to 75 microg/kg/min, and fentanyl, 10 microg/kg/h. In group I (n = 17), induction was achieved with IV thiopental sodium, 3 to 5 mg/kg, and fentanyl, 1 to 2 microg/kg, and was maintained with 1% isoflurane and fentanyl, 10 mug/kg/h. Blood and TBA samples were obtained at 6 and 4 stages, respectively. MEASUREMENTS AND MAIN RESULTS: Serum IL-6 and TBA IL-6 levels were similar in the 2 groups at all stages (p > 0.05). CONCLUSION: The present results show that ketamine anesthesia does not provide superiority over isoflurane anesthesia with respect to serum and TBA IL-6 levels. 相似文献
733.
Hacihanefioglu B Somunkiran A Mahmutoglu I Sercelik A Toptani S Kervancioglu E 《Fertility and sterility》2002,77(3):526-528
OBJECTIVE: To investigate the effect of an angiotensin-converting enzyme inhibitor, lisinopril, on serum androgen and sex-hormone-binding globulin (SHBG) levels in hypertensive women with polycystic ovary syndrome (PCOS). DESIGN: Prospective, observational study. SETTING: Infertility Clinic of the Sani Konukoglu Hospital, Gaziantep, Turkey. PATIENT(S): Ten hypertensive women with PCOS. INTERVENTION(S): Lisinopril, 10 mg/day, for 4 weeks. MAIN OUTCOME MEASURE(S)): Serum levels of gonadotropins, DHEAS, total T, free T, 17 alpha-hydroxyprogesterone (17-OHP), androstenedione, E2, SHBG, TSH, and PRL were determined. RESULT(S): Hypertension treatment with lisinopril (10 mg/day for 4 weeks) resulted in a statistically significant decrease in serum free T levels. However, there was no difference in the SHBG levels. CONCLUSION(S): Use of lisinopril, an angiotensin-converting enzyme inhibitor, results in decreased free T levels independently of SHBG. It may affect the free T levels by affecting the ovarian renin-angiotensin system. 相似文献
734.
Durmus E Inan O Celik I Sur E Ozkan Y Acar A Aydin MF 《Journal of biomedical materials research. Part B, Applied biomaterials》2005,72(2):322-327
In this study, embryotoxic effects of five commercially available dental alloys were investigated by using fertilized hens' eggs. One sample of each alloy was conditioned in one of the conditioning media, physiological saline (PS), 0.1 M phosphate-buffered saline (PBS, pH 7.4), and 0.1 M protein (3% bovine serum albumin, BSA) containing PBS (pH 6.8), respectively. The test solutions were injected into the fertilized hen's eggs via air sac at the beginning of the incubation. Various concentrations of a highly embryotoxic substance, AFB1, was also used as positive control test material. Mortality of the AFB1 treatment groups increased with increasing concentrations of AFB1 and the mortality values were significantly (p < 0.05) higher than those of the controls and eluent injected groups. The eluents of five commercially available dental alloys tested in the study did not have significant embryotoxic effects. Cu- and Pd-containing alloys displayed relatively high but statistically insignificant embryotoxic effects. Chick embryo might be used in determination of the embryotoxic effects of the dental alloys with its several advantages. Nevertheless, the test should be further standardized and new methods such as micronucleus test showing possible genotoxic effects of the materials should be used. 相似文献
735.
OBJECTIVE: To obtain normative data for fetal pharyngeal diameter and to investigate the ability to visualize pharynx at different gestational ages during routine prenatal sonography. METHODS: Sonographic studies were performed in 292 consecutive pregnant women. The diameters of the pharynx were measured and our ability to visualize pharynx was evaluated at different gestational ages. RESULTS: Sonographic measurements of the pharyngeal diameter were obtained in 153 of the 292 fetuses. The diameter of the pharynx increased from a mean of 4.5+/-0.53 mm at 16 weeks to 9.1+/-1.72 mm at 36 weeks. Pharyngeal diameters showed a significant positive relationship with advancing gestational age (p<0.0001, R2=0.571). The differences in visualization among different gestational age groups were found to be significant (p<0.05 by Chi-Square). CONCLUSION: This study reports normative data for fetal pharyngeal diameter. Pharyngeal measurements were similar to previous reports in the literature. Our success in visualizing the pharynx was best between 21 and 30 weeks of gestation. This period might be the optimum time for evaluating fetal pharynx. 相似文献
736.
Cagatay?OysuEmail author Murat?Topak Oner?Celik H.?Baki?Yilmaz A.?Asli?Sahin 《European archives of oto-rhino-laryngology》2005,262(10):839-843
The purpose of this study was to evaluate the short-term effects of the electromagnetic fields (EMF) of mobile phones on human auditory brainstem responses. This prospective study of healthy adults evaluated the influence of EMF. Eighteen healthy adult volunteers participated in this study. Mobile telephones emitting signals in the region of 900 MHz and with the highest SAR value of 0.82 W/kg were positioned in direct contact to the right ear, which was exposed to the phone signal for 15 min before and after ABR testing with click stimuli of 60 and 80 dB nHL intensities. The latencies of the waves and interwave latencies were measured on screen by an experienced audiologist. The differences of the mean latencies of waves I, III and IV were not significant in initial and post-exposure ABR measurements at both 60 and 80 dB nHL stimulus levels ( P >0.05). Similarly, differences of the mean interwave intervals I-III, I-V and III-V remained insignificant at the initial and postexposure ABR measurements at stimulus levels of both 60 and 80 dB nHL ( P >0.05). Acute exposure to the EMF of mobile phones does not cause perturbations in ABR latencies. However, these negative results should not encourage excessive mobile communication, because minor biological and neurophysiological influences may not be detectable by the current technology. 相似文献
737.
Sexual life following total abdominal hysterectomy 总被引:2,自引:0,他引:2
Kuscu NK Oruc S Ceylan E Eskicioglu F Goker A Caglar H 《Archives of gynecology and obstetrics》2005,271(3):218-221
Aim The goal of this study was to evaluate the effect of total abdominal hysterectomy (TAH) on sexual lives of patients in the postoperative period.Materials and methods Eighty-six patients who accepted to participate a phone-questionnaire were recruited in the study after TAH or TAH + BSO. They were asked about sexual desire, pain during sexual intercourse, frequency and satisfaction of sexual intercourse at pre- and postoperative periods, and loss of feeling a woman in the postoperative period. Sexual desire, pain during sexual intercourse, loss of feeling a woman questions were answered as yes or no, number of weekly sexual intercourse was recorded, and satisfaction was graded as no = 0, mild = 1 and complete = 2 points.Results While sexual desire and frequency were found to be significantly lower (p=0.026 and p=0.01 respectively), no difference was noted in dyspareunia and satisfaction. When the patients were divided into two groups according to the presence of endogenous or exogenous estrogen, no difference was seen between the two groups in the postoperative period.Conclusion We concluded that the effect of TAH or TAH+BSO operations were mainly on sexual desire and the number of weekly intercourse, and estrogen in the postoperative period did not make any difference between the two groups. 相似文献
738.
Reduced heart rate volatility: an early predictor of death in trauma patients 总被引:4,自引:0,他引:4 下载免费PDF全文
Grogan EL Morris JA Norris PR France DJ Ozdas A Stiles RA Harris PA Dawant BM Speroff T 《Annals of surgery》2004,240(3):547-556
OBJECTIVE: To determine if using dense data capture to measure heart rate volatility (standard deviation) measured in 5-minute intervals predicts death. BACKGROUND: Fundamental approaches to assessing vital signs in the critically ill have changed little since the early 1900s. Our prior work in this area has demonstrated the utility of densely sampled data and, in particular, heart rate volatility over the entire patient stay, for predicting death and prolonged ventilation. METHODS: Approximately 120 million heart rate data points were prospectively collected and archived from 1316 trauma ICU patients over 30 months. Data were sampled every 1 to 4 seconds, stored in a relational database, linked to outcome data, and de-identified. HR standard deviation was continuously computed over 5-minute intervals (CVRD, cardiac volatility-related dysfunction). Logistic regression models incorporating age and injury severity score were developed on a test set of patients (N = 923), and prospectively analyzed in a distinct validation set (N = 393) for the first 24 hours of ICU data. RESULTS: Distribution of CVRD varied by survival in the test set. Prospective evaluation of the model in the validation set gave an area in the receiver operating curve of 0.81 with a sensitivity and specificity of 70.1 and 80.0, respectively. CVRD predict death as early as 24 hours in the validation set. CONCLUSIONS: CVRD identifies a subgroup of patients with a high probability of dying. Death is predicted within first 24 hours of stay. We hypothesize CVRD is a surrogate for autonomic nervous system dysfunction. 相似文献
739.
740.
Büyüköztürk S Gelincik A Ozşeker F Genç S Savran FO Kiran B Yillar G Erden S Aydin F Colakoğlu B Dal M Ozer H Bilir A 《Journal of ethnopharmacology》2005,100(3):295-298
Nigella sativa Linn. (Ranunculaceae) is known to have beneficial effects on a wide range of diseases including asthma. However, the mechanism of action in asthma and other allergic diseases is not entirely clear. The present study was planned to evaluate the effects of Nigella sativa on cytokine production of splenic mononuclear cells in ova-sensitized mice. Nineteen two-month-old BALB/c mice were given 0.3 mL of Nigella sativa oil by oro-eosophageal cannula once a day for a month. The control group consisting of 10 mice took 0.3 mL of 0.9% saline solution by the same route for the same period. In the third week of the study, all mice were sensitized by means of intraperitoneal injections of 20 μg of ovalbumin (OVA-Grade VI, Sigma). Ova injections were repeated three times with 7-day intervals. After another week, all mice were sacrificed by means of cervical dislocation. Then the splenic mononuclear cells (MNCs) of mice were cultured with OVA or Concavalin A (Con-A). From the culture supernatants, IL-4, IL-10 and IFN-γ were assessed by means of ELISA. The cytokine production of splenic MNCs of mice that were given Nigella sativa for 30 days was not significantly different than those who took saline solution instead. In conclusion, Nigella sativa oil seems not to have an immunomodulatory effect on Th1 and Th2 cell responsiveness to allergen stimulation. 相似文献