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排序方式: 共有2282条查询结果,搜索用时 15 毫秒
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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
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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
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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
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Buhimschi CS Abdel-Razeq S Cackovic M Pettker CM Dulay AT Bahtiyar MO Zambrano E Martin R Norwitz ER Bhandari V Buhimschi IA 《American journal of perinatology》2008,25(6):359-372
We hypothesized that abnormal fetal heart rate monitoring patterns (FHR-MPs) occur more often in pregnancies complicated by intra-amniotic inflammation. Therefore, our objective was to examine the relationships among FHR-MP abnormalities, intra-amniotic inflammation and/or infection, acute histological chorioamnionitis, and early-onset neonatal sepsis (EONS) in pregnancies complicated by preterm birth. Additionally, the ability of various FHR-MPs to predict EONS was investigated. FHR-MPs from 87 singleton premature neonates delivered within 48 hours from amniocentesis (gestational age, mean +/- SD: 28.9 +/- 3.3 weeks) were analyzed blindly using strict National Institute of Child Health and Human Development criteria. Strips were evaluated at three time points: at admission, at amniocentesis, and prior to delivery. Intra-amniotic inflammation was established based on a previously validated proteomic fingerprint (mass-restricted score). Diagnoses of histological chorioamnionitis and EONS were based on well-recognized pathological, clinical, and laboratory criteria. We determined that fetuses of women with severe intra-amniotic inflammation had a higher FHR baseline throughout the entire monitoring period and an increased frequency of a nonreactive FHR-MP at admission. Of all FHR-MPs, a nonreassuring test at admission had 32% sensitivity, 95% specificity, 73% positive predictive value, 77% negative predictive value, and 76% accuracy in predicting EONS. Although a nonreassuring FHR-MP at admission was significantly associated with EONS after correcting for gestational age (odds ratio, 5.6; 95% confidence interval, 1.2 to 26.2; P = 0.030), the majority of the neonates that developed EONS had an overall reassuring FHR-MP. Nonreassuring FHR-MPs at either amniocentesis or delivery had no association with EONS. We conclude that in cases complicated by preterm birth, a nonreassuring FHR-MP at the initial evaluation is a specific but not a sensitive predictor of EONS. An abnormal FHR-MP can thus raise the level of awareness that a fetus with EONS may be born, but it is not a useful clinical indicator of the need for antibiotic treatment of the neonate. 相似文献
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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
8.
Yazar S Yaman O Demirtaş F Yalçin S Yücesoy M Sahin I 《Acta gastro-enterologica Belgica》2002,65(4):241-244
A 52 year-old male patient with idiopathic hepatic cirrhosis complaining of diarrhea and weakness was accepted to the gastroenterology clinic. In order to find out the causative etiologic agent of diarrhea, stool samples were examined by different methods and stained using modified Kinyoun's acid-fast stain. Following examination, approximately 9 microns diameter, acid-fast variable wrinkled spheres were seen and diagnosed as Cyclospora cayetanensis. Confirmation of the diagnosis was established by fluorescent microscope (380 to 420 nm excitation filter), which showed bright green to intense blue autofluorescent oocysts. It has been shown that, Cyclospora cayetanensis is a coccidian parasite mainly found in immunocompromised patients and that it may be the agent of prolonged diarrhea. Only three cyclosporiosis cases have been previously reported in our country; all three cases were AIDS patients. We report here a further case of Cyclospora cayetanensis infection in a patient with hepatic cirrhosis and we consider that this is the first case, which was reported in hepatic cirrhosis. 相似文献
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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
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