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71.
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BACKGROUND: This study was planned to evaluate the efficiency of the 11-14 week scan in detecting fetuses with major fetal structural abnormalities. METHODS: Some 1,290 pregnant women were submitted to a routine ultrasound scan between the 11th and 14th week after the detection of the fetal viability. The fetal anatomy was examined transabdominally, and in suspected cases transvaginally. Following the scans, the patients were examined in the second or third trimester of pregnancy. Fetal structural abnormalities classified as major and early onset were noted. Isolated choroid plexus cysts, cardiac defects not requiring treatment, mild ventriculomegaly, and mild renal pelviectasis in second trimester were not included. RESULTS: Twenty-four (1.86%) fetuses with various defects were identified, and 17 of these were diagnosed at the 11-14 week scan. The antenatal ultrasound detection rate of the fetuses with major anomalies was 95%, and 70% were detected in the first-trimester assessment. Four cardiac defects associated with genetic syndromes or requiring operation were included (0.31%) in this series. Two of the fetuses with cardiac defects (50%) had an increased nuchal translucency thickness. In this group, none of the fetuses with karyotype anomalies was born alive. CONCLUSIONS: The first-trimester scan is important in routine antenatal care for early detection of fetal defects, and determination of the fetuses at risk of cardiac anomalies and genetic syndromes.  相似文献   
73.
The present work aimed to investigate the dry sliding wear behaviors of hybrid polymer matrix composites made up of Kevlar, bamboo, palm, and Aloe vera as reinforcement materials of varying stacking sequences, along with epoxy as the matrix material. Three combinations of composite laminates with different stacking sequences such as AB, BC, and CA were fabricated by a vacuum-assisted compression molding process. The influence of composite laminates fabricated through various stacking sequences and dry sliding wear test variables such as load, sliding distance, and sliding velocity on the specific wear rate and co-efficient of friction were investigated. Experiments were designed and statistical validation was performed through response surface methodology-based D-optimal design and analysis of variance. The optimization was performed using grey relational analysis (GRA) to identify the optimal parameters to enhance the wear resistance of hybrid polymer composites under dry sliding conditions. The optimal parameters, such as composite combinations of CA, a load of 5 N, a sliding velocity of 3 m/s, and a sliding distance of 1500 m, were obtained. Furthermore, the morphologies of worn-out surfaces were investigated using SEM analysis.  相似文献   
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Neoplastic or dysplastic neuronal tissue in the brain stem and cerebellum can become epileptogenic in pediatric patients. However, it is unknown whether such tissue may transform intrinsic properties of the human cerebellum, making it capable of generating epileptic population activity. We noninvasively detected epileptiform signals unaveraged in a pediatric patient with epilepsy due to a tumor in the middle cerebellar peduncle. Analysis of generators of the signals revealed that the cerebellum ipsilateral and contralateral to the tumor was the dominant interictal spike generator and could initiate ictal activity, suggesting that human cerebellum may become capable of intrinsically generating epileptic activity. ANN NEUROL 2020;88:418–422.  相似文献   
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Purpose The appetite suppressants fenfluramine and dexfenfluramine were widely prescribed before being withdrawn from the market in 1997. Both drugs are known to have the potential to damage brain serotonin (5-HT) axons and axon terminals in animals, including nonhuman primates. This study used quantitative positron emission tomography (PET) with [11C] McN5652, a serotonin transporter (SERT) ligand to determine whether humans previously exposed to fenfluramines showed reductions in SERT binding parameters. Procedures Subjects previously treated with fenfluramines for weight loss (N = 15) and age-matched controls (N = 17) underwent PET studies with [11C] McN5652. Global and regional distribution volumes (DVs) of [11C] McN5652 were compared in the two subject groups using parametric statistical analyses. Results Compared to controls, subjects previously exposed to fenfluramines had significant reductions in [11C]McN5652 binding in 14 of 15 regions of interest, more than four years after drug discontinuation. Conclusions These results are the first to provide direct evidence for fenfluramine-induced 5-HT neurotoxicity in humans.  相似文献   
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STUDY OBJECTIVE: The aim of this study is to describe a safe technique without any ureteral, bladder, and major vessel injuries in laparoscopic hysterectomy with a CO2 laser technique. DESIGN: Prospective study (Canadian Task Force classification II-3). SETTING: Centre Hospitalier Interrégional Edith Cavell, Department of Obstetrics and Gynecology, Endoscopic Laser Surgery Center, Bruxelles, Belgium; and Kadir Has University, Metropolitan Florence Nightingale Hospital, Istanbul, Turkey. PATIENTS: One thousand one hundred twenty women with benign diseases. INTERVENTIONS: Laparoscopic-assisted vaginal hysterectomy (LAVH) or laparoscopic hysterectomy (LH). MEASUREMENTS AND MAIN RESULTS: Between 1992 and 2004, in 1120 women with benign diseases, consecutive LAVH or LH was planned. During laparoscopic hysterectomy, at all stages, bipolar forceps was used for hemostasis, and a CO2 laser was used for vaporization and excision. The total operating time was 35 to 180 minutes, with a median of 52 minutes (range 35-163) for LAVH (n = 542) and 55 minutes (range 42-180) for LH (n = 552). Operations were successfully completed laparoscopically in 98.8% of the patients. The mean hospital stay was 2 days. The overall major complication rate was 1%. No ureteral, bladder, or major vascular injury occurred. CONCLUSION: The technique we used in our study is safe and effective in the prevention of ureteral, vesical, and vascular injuries during LAVH and LH; moreover, the use of bipolar coagulation and a CO2 laser in endoscopic surgery results in a shorter duration of operation. This technique provides all the advantages of both laparoscopic and vaginal surgery.  相似文献   
80.

Background

Ginger (Zingiber officinale) is a well known and extensively used antioxidant in traditional remedies. In this study, we aimed to investigate the effects of ginger powder on ovarian folliculogenesis and implantation in rats.

Methods

There were two study groups. In the 5-day treatment group (one estrous cycle), 100 mg ginger powder, 200 mg ginger powder or distilled water was given for 5 days to the three subgroups each containing seven rats. In the 10-day treatment group, same doses were given for 10 days (two estrous cycle) to the three subgroups each containing seven rats. At the end of the 5th and 10th days, ovarian volumes, ovarian weights, primordial follicles, antral follicles, atretic follicles, and corpus luteum counts were assessed. To evaluate the angiogenic effects of ginger, vascular endothelial growth factor (VEGF) and for the antioxidant effects of ginger endothelial nitric oxide synthase (eNOS) were examined in the ovaries and in the endometrium immunohistochemically.

Results

In the 5-day treatment group, antral follicle count and ovarian stromal VEGF were significantly high in the 100 mg ginger subgroup in comparison to the control group (p < 0.05). In the 10-day treatment group, endometrial VEGF and ovarian stromal eNOS were significantly high in the 100 mg ginger subgroup in comparison to the control group (p < 0.05). There was no statistically significant difference at 200 mg ginger dose both in 5-day and 10-day treatment groups.

Conclusion

The increases in the antral follicle count and ovarian stromal VEGF in the 100 mg/5-day treatment subgroup indicate that ginger have positive effects on folliculogenesis in short term with low dose. Additionally, ginger may enhance implantation in rats in long term with low dose.  相似文献   
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