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91.
Tanja Stachon Mahsa Nastaranpour Berthold Seitz Eckart Meese Lorenz Latta Suphi Taneri Navid Ardjomand Nra Szentmry Nicole Ludwig 《Investigative ophthalmology & visual science》2022,63(8)
PurposeEvaluation of mRNA and microRNA (miRNA) expression in epithelium and stroma of patients with keratoconus.MethodsThe epithelium and stroma of eight corneas of eight patients with keratoconus and eight corneas of eight non-keratoconus healthy controls were studied separately. RNA was extracted, and mRNA and miRNA analyses were performed using microarrays. Differentially expressed mRNAs and miRNAs in epithelial and stromal keratoconus samples compared to healthy controls were identified. Selected genes and miRNAs were further validated using RT-qPCR.ResultsWe discovered 170 epithelial and 1498 stromal deregulated protein-coding mRNAs in KC samples. In addition, in epithelial samples 180 miRNAs and in stromal samples 379 miRNAs were significantly deregulated more than twofold compared to controls. Pathway analysis revealed enrichment of metabolic and axon guidance pathways for epithelial cells and enrichment of metabolic, mitogen-activated protein kinase (MAPK), and focal adhesion pathways for stromal cells.ConclusionsThis study demonstrates significant differences in the expression and regulation of mRNAs and miRNAs in the epithelium and stroma of Patients with KC. Also, in addition to the well-known target candidates, we were able to identify further genes and miRNAs that may be associated with keratoconus. Signaling pathways influencing metabolic changes and cell contacts are affected in epithelial and stromal cells of patients with keratoconus. 相似文献
92.
蓣知子皂甙IV的结构 总被引:5,自引:1,他引:5
从木通科木通属植物白木通[Akebia trifoliata(Thunb.)Koidz.var.australis(Diels)Rehd]种子的乙醇提取物中以硅胶层析等方法得四种三萜皂甙。其中甙IV是新天然产物,命名为蓣知子皂甙IV(yuzhiziosideIV)。根据化学和光谱分析,确定甙IV的结构为3-O-β-D-吡喃木糖基-(1→2)-a-L-吡喃阿拉伯糖齐墩果酸-28-O-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖酯甙。另外皂甙B(I)、皂甙C(II)和皂甙D(III)为已知物。这些化合物在白木通种子中均是首次得到。 相似文献
93.
Ludwig AK Katalinic A Jendrysik J Thyen U Sutcliffe AG Diedrich K Ludwig M 《Reproductive biomedicine online》2008,17(3):403-409
There are only scarce data on the incidence of spontaneous pregnancy in infertility patients. Contraception after infertility treatment is another topic that has been neglected so far. Therefore, a questionnaire was sent to 1614 couples with a child conceived by intracytoplasmic sperm injection (ICSI) aged 4-6 years. A total of 899 couples responded (response rate 55.7%). A total of 10.9% of couples had used contraception. Of the couples that had actively tried to conceive, 20.0% had conceived spontaneously, resulting in a live-birth rate of 16.4%. 74.5% of these pregnancies were conceived within 2 years after delivery. A further 26.6% of couples conceived again by ICSI, with a live-birth rate of 20.9%. Maternal age was the only prognostic factor for spontaneous conception. Parents of multiples after ICSI did not have a higher chance of spontaneous conception than parents of singletons. Couples can be counselled that one out of five couples conceive spontaneously after successful ICSI. Even when assuming that none of the families that were lost to follow-up had conceived spontaneously, one out of eight couples would have conceived spontaneously. Therefore, it is important to counsel patients about the possibility of natural conception and necessity to use contraception despite their history of subfertility. 相似文献
94.
This paper deals with the question of whether measuring hormones is necessary in eumenorrhoeic infertility patients. The answer presented here is yes, but there are some remaining and debatable problems. In our opinion, eumenorrhoea results from regular folliculogenesis, ovulation and luteal function. To be time- and cost-effective, only a limited number of hormones should be measured and assessment of the luteal phase in an eumenorrhoeic patient by measuring oestradiol and progesterone is questionable. The paper discusses the questions on the basis of the currently available literature. 相似文献
95.
OBJECTIVE: To describe mortality and morbidity of neonates born at <26 weeks' gestation in a contemporary population-based cohort. METHODS: We analyzed data of neonates born at <26 weeks between 1998 and 2003 in the Federal State of Hesse, Germany. Survival was calculated at 28 days and at discharge from hospital. RESULTS: Out of a total of 800 births, 572 infants were liveborn. Among those admitted for neonatal intensive care, 62.3% survived until day 28. Among the neonates followed until death or discharge, 59.6% were discharged home. Logistic regression analyses showed the following variables to be associated with an increased risk of death: Twins (Odds Ratio (OR) 3.7; 95% Confidence Interval (CI) 1.34-10.26), multiple birth >or=3 (OR 8.14; CI 1.23-53.86), intraventricular hemorrhage (IVH) >or=grade III (OR 4.79; CI 1.89-12.14), clinical risk index for babies score >15 (OR 2.9; CI 1.09-7.76), and a gestational age or=grade III and/or periventricular leukomalacia in 15%, and severe retinopathy of prematurity in 29.8%. CONCLUSIONS: This study provides outcome data derived from a contemporary population-based cohort. Mortality and complication rates remain high. 相似文献
96.
Androgens and insulin are endocrine key players in the pathophysiology of polycystic ovary syndrome (PCOS), a heterogenic condition of unexplained etiology and a suspected genetic background. Androgens mediate the clinical phenotype of the disease. Therefore,all criteria of the recent PCOS consensus definition are based on their biological effects. Insulin resistance, followed by compensatory hyperinsulinemia, is frequently found in patients with PCOS. Insulin resistance is correlated with a risk of metabolic complications of PCOS, and recent research has focused on possible long-term health consequences of the syndrome. Newest molecular genetic findings at the receptor level of both androgens and insulin support their pivotal role in PCOS. These results could help to better characterize the heterogenic disorder, enabling a refinement of existing individualized therapeutic strategies. 相似文献
97.
98.
99.
Schettler Gotthart Messerschmidt Karl Ludwig 《Zeitschrift für die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie》1950,116(1):67-74
Research in Experimental Medicine - 相似文献
100.
Ohne Zusammenfassung 相似文献