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排序方式: 共有1597条查询结果,搜索用时 15 毫秒
1.
Ahmet Tektemur Ebru Etem Önalan Nalan Kaya Tektemur Serap Dayan Cinkara Ayten Kılınçlı Çetin İbrahim Tekedereli Tuncay Kuloğlu Gaffari Türk 《Andrologia》2021,53(2):e13954
Male infertility is a global health problem, and the underlying molecular mechanisms are not clearly known. Ion channels and microRNAs (miRNAs), known to function in many vital functions in cells, have been shown to play a significant role in male infertility through changes in their expressions. The study aimed to evaluate the alterations of testicular and/or spermatozoal potassium voltage-gated channel subfamily J member 11 (KCNJ11), Cystic fibrosis transmembrane conductance regulator (CFTR), miR-let-7a and miR-27a expressions in carbamazepine-related male infertility. Here, we showed that carbamazepine reduced sperm motility, increased abnormal sperm morphology, and impaired hormonal balance as well as increased relative testis weight and decreased relative seminal vesicle weight. On the other hand, downregulated KCNJ11 and upregulated miR-let-7a expressions were determined in testis (p < .05). Also, downregulated KCNJ11 and upregulated CFTR and miR-27a expressions were found in spermatozoa (p < .05). Interestingly, altered testicular KCNJ11 and miR-let-7a expressions were correlated with decreased sperm motility and elevated sperm tail defect. Besides, spermatozoal CFTR and miR-27a expressions positively correlated with sperm tail defects. The results indicated a significant relationship between ion channel and/or miRNA expression alterations and impaired sperm parameters due to carbamazepine usage. 相似文献
2.
Fatma Yildiztekin Ebru Erol Mahmut Yildiztekin Atilla L. Tuna Mehmet Ozturk 《Pharmaceutical biology》2016,54(9):1557-1563
Context We report the first ever chemical/biochemical study on Crocus mathewii Kerndorff (Iridaceae) – a Turkish endemic angiosperm. This plant has never been explored for its phytochemistry and bioactivities.Objective This study explores C. mathewii corm and aerial parts for the chemical and biological properties of hexane, ethyl acetate, methanol and water fractions of the extracts.Material and methods Plant material (20 g) was extracted by methanol (250?mL?×?5, 3 days each) and fractioned into hexane, ethyl acetate, methanol and water. All fractions were subjected to β-carotene–linoleic acid, DPPH·, ABTS·+, CUPRAC, metal chelating and tyrosinase inhibition activities. Hexane fractions were submitted to GC–MS analysis.Results Ethyl acetate fractions showed excellent IC50 values in DPPH· (aerial 36.21?±?0.76 and corm 33.87?±?0.02?mg/L) and ABTS·+ (aerial 33.01?±?0.79 and bulb 27.87?±?0.33?mg/L); higher than the IC50 of the standard α-tocopherol (DPPH 116.25?±?1.97; ABTS 52.64?±?0.37?mg/L), higher than BHA in DPPH (57.31?±?0.25?mg/L), but slightly lower in ABTS (19.86?±?2.73?mg/L). Methanol extract of aerial parts also showed higher activity than α-tocopherol in DPPH (85.56?±?11.51?mg/L) but slightly less (72.90?±?3.66?mg/L) than both the standards in ABTS. Linoleic (aerial 53.9%, corm 43.9%) and palmitic (aerial 22.2%, corm 18%) were found as the major fatty acids.Discussion and conclusion Some fractions of C. mathewii showed higher antioxidant activities than the standards. There is a need to explore more about this plant. 相似文献
3.
4.
Uckuyu A Ozcimen EE Sevinc FC Zeyneloglu HB 《Journal of minimally invasive gynecology》2008,15(4):472-475
We wanted to investigate the effect of misoprostol administered vaginally before operative hysteroscopy on cervical dilation, complications, and failure rates in patients who have undergone cesarean section and who have never delivered vaginally. Sixty patients who had undergone cesarean section, who had never delivered vaginally before, and were about to undergo hysteroscopy for various intrauterine lesions were included in this randomized controlled study. Thirty-two patients in the study group were given misoprostol 400 microg, and 28 patients in the control group were given placebo (hexetidine pill) vaginally twice, 6 and 12 hours before the procedure. Primary endpoints were cervical width detected with Hegar dilators and complication and failure rates. Mean cervical width was greater in patients in the study group (6.5 +/- 0.8) than it was in patients in the control group (3.0 +/- 0.6), (p = .0001). Complication and failure rates were lower in patients in the study group (p = .01). Administration of vaginal misoprostol before hysteroscopy proved to be effective in cervical ripening and in reducing complication and failure rates. 相似文献
5.
Arslan M Bocca S Arslan EO Duran HE Stadtmauer L Oehninger S 《Journal of assisted reproduction and genetics》2007,24(4):111-117
Purpose: To investigate the effect of the cumulative exposure to estradiol (E2) during the follicular phase on IVF outcome.
Methods: Patients were stimulated with recombinant FSH after GnRH agonist suppression and had a day 3-embryo transfer. Estrogen exposure
was determined as the area under the curve (AUC) for serum E2 levels measured from the first day of stimulation through the day after hCG administration.
Results: E2 AUC thresholds for 10th and 90th percentiles were 4704 pg/ml and 16338 pg/ml, respectively. The pregnancy and implantation
rates were highest in the 10th–90th percentile group, and were statistically higher in this group than in the >90th percentile
group (54.6% vs. 33.3% and 24.8% and 12.9%, respectively, for pregnancy and implantation rates, P < 0.05). Recovered mature oocytes, fertilization, and number and mean score of transferred embryos were similar.
Conclusions: High cumulative E2 exposure during the follicular phase of IVF cycles has detrimental effects on implantation. 相似文献
6.
Ebru Akgul M.D. Utku Kutuk M.D. Sibel Ertek M.D. Mustafa Cesur M.D. Sengul Cehreli M.D. Hasan Fehmi Tore M.D. Gurbuz Erdogan M.D. 《Echocardiography (Mount Kisco, N.Y.)》2011,28(1):15-21
Objective: Autoimmune chronic thyroiditis (ACT) is characterized by lymphocyte infiltration in the thyroid gland and the presence of antithyroid antibodies in serum. Medical treatment does not affect antibody levels and treatment decision is not definite yet for the euthyroid patients. We aimed to evaluate cardiac autonomic function and global left ventricular performance in autoimmune euthyroid chronic thyroiditis and determine the need for medical treatment. Method: We studied 30 ACT patients and 25 healthy control subjects. Cardiac autonomic function is evaluated by heart rate recovery (HRR). Global left ventricular performance is evaluated by two‐dimensional echocardiography and pulsed‐wave tissue Doppler echocardiography. Results: There was no difference between patients and controls with respect to clinical and biochemical parameters except hemoglobin (13.67 ± 1.25 g/dL, 14.51 ± 1.35 g/dL, p:0.047) and low density lipoprotein (120.71 ± 24.91 mg/dL, 100.55 ± 14.73 mg/dL, p: 0.003). Tei index was significantly higher in ACT group (0.521 ± 0.074, 0.434 ± 0.034, P < 0.0001). E′/A′ was found to be significantly lower (1.234 ± 0.42, 1.750 ± 0.291, P < 0.0001) and E/E′ was found to be higher than the controls (8.482 ± 0.449, 6.039 ± 0.209, P < 0.0001). HRR was significantly lower than the controls (20 ± 4 BPM, 30 ± 8 BPM, P < 0.0001). Conclusion: Although left ventricular performance is found to be normal by conventional echocardiographic methods, it is found to be impaired when Tei index and tissue Doppler parameters are used. Cardiac autonomic function is also impaired in ACT patients. As a result of these cardiac changes, medical treatment may be considered earlier, even at the euthyroid stage. (Echocardiography 2011;28:15‐21) 相似文献
7.
Pupose
Obstructive sleep apnea (OSA) is associated with various metabolic disorders, and oxidative stress was suggested to play an important role. In the present study, we aimed to investigate serum adiponectin and oxidative stress markers, especially protein carbonyls, and to evaluate the correlation between these parameters and lipid, insulin and fasting glucose concentrations in OSA patients and controls. 相似文献8.
Xanthelasmas of the upper gastrointestinal tract 总被引:1,自引:0,他引:1
Gencosmanoglu R Sen-Oran E Kurtkaya-Yapicier O Tozun N 《Journal of gastroenterology》2004,39(3):215-219
Background Gastric xanthelasma is a benign and uncommon lesion with a variably reported frequency, while esophageal and duodenal xanthelasmas are quite rare.Methods Seventeen patients who had the diagnosis of xanthelasma in the upper gastrointestinal tract were analyzed retrospectively with respect to their demographic, clinical, endoscopic, and histopathologic features. All lesions suspected as xanthelasma were totally removed by either hot biopsy forceps or a snare with the technique of endoscopic mucosal resection.Results The incidence of upper gastrointestinal xanthelasmas in 7320 patients who had upper gastro-intestinal endoscopy was 0.23%. There were 9 (53%) men and 8 (47%) women, with a median age of 50 years (range, 24–80 years). The most common location of xanthelasmas was the stomach (76%), followed by the esophagus (12%) and duodenum (12%). All lesions were observed as yellow-white colored plaques at endoscopy. Multiple xanthelasmas were detected in 4 patients (24%); in the duodenum in 2, esophagus in 1, and stomach in 1. One patient had xanthelasma within a gastric hyperplastic polyp. The size of the lesion was less than 5mm in diameter in 14 (82%) patients and between 5 and 10mm in diameter in 3 (18%). Thirteen (76%) patients had moderate to severe atrophic gastritis, while the remainder had normal gastric mucosa.Conclusions Xanthelasmas of the upper gastrointestinal tract were mostly located in the stomach in the present series, which includes the second and third reported cases of duodenal xanthelasma, the second case of xanthelasma developed within a hyperplastic gastric polyp, and the fourth and the fifth cases of esophageal xanthelasma. 相似文献
9.
Ceyhan M Yildirim I Tekeli A Yurdakok M Us E Altun B Kutluk T Cengiz AB Gurbuz V Barin C Bagdat A Cetinkaya D Gur D Tuncel O 《American journal of infection control》2008,36(6):453-457
Three clusters of Chryseobacterium meningosepticum infections in a tertiary health center in July 2006 and January 2007 involving 8 newborns and 5 older children were investigated. The index patient was from the neonatal intensive care unit, and the older patients were from other pediatric wards. Cultures were obtained from the environment and from health care workers' hands as part of an outbreak investigation. C meningosepticum was isolated from hand cultures obtained from a senior resident and from environmental cultures obtained from powdered infant formula, an electrical button, a computer keyboard, phone, a doorknob, and an Ambu bag. Antibiogram typing and enterobacterial repetitive intergenic consensus sequence polymerase chain reaction indicated that all of the isolates were epidemiologically related. Nine patients improved on antimicrobial treatment, and 4 premature infants died after the infection. C meningosepticum is a well-known etiologic agent for nosocomial infections involving newborns and immunocompromised patients. Wet and dry environmental surfaces and equipment may act as a source or play a role in disseminating the microorganism. Outbreaks may be controlled with strong emphasis on infection control measures. 相似文献
10.
AIM: To determine the effects of pentoxifylline, a methyl xanthine derivative on hepatic cell production of uninterferred lobe after portal vein branch ligation. METHODS: Sixty-six rats were randomly allocated into 9 groups with 8 rats in PVL groups and 6 rats in sham operation groups. The portal branches of the median and the lateral liver lobes, corresponding to approximately 70% of the liver volume were ligated in the PVL groups. The control group received 0.9% NaCl solution. The rats in the treatment groups received pentoxifylline at the dose of 50 mg/kg/dy. After 1, 2, 4 days of portal vein ligation in both PVL and PVNL lobes the levels of adenine nucleotides were determined and flowcytometric analysis of cell cycles were performed. RESULTS: On the first day of portal branch ligation energy charge was significantly lower, in pentoxifylline treated group comparing to pentoxifylline untreated group, both in PVL and PVNL lobes (P<0.05). Proliferative indexes were 0.38 and 0.29 in pentoxifylline treated and pentoxifylline untreated PVNL lobes respectively (P<0.05). CONCLUSION: Pentoxifylline treatment resulted in an increase of percentage of calls entering mitosis phase on the first day after PVL, somehow accelerating the regeneration process. 相似文献