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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   
13.
AIM: Recent findings show that the vaginal mucosa can develop an allergic response to environmental allergens and there is a strong association between atopy and some recurrent vulvovaginal infections. In this study, we investigated prospectively the rate of atopy in patients with recurrent vulvovaginitis of undetermined etiology (RVV). MATERIAL AND METHODS: After being investigated by a gynecologist, 35 patients with RVV who were considered as undetermined etiology formed the study group. The control group consisted of 150 healthy females. Study and control groups were investigated for atopy by means of skin prick test for common aeroallergens. Associated allergic disease and familial atopy history of the subjects were recorded. RESULTS: The rate of atopy (11/35; 31.4% vs 9/150; 6%) was significantly higher (P < 0.001) in the study group than in the controls. Familial history of atopy was significantly more frequent in the study group than in the controls (10/35; 28.6% vs 8/150; 5.3%, P < 0.05). RVV in atopics is more associated with seasonal rhinitis than in nonatopics (5/11; 45.4% vs 2/24; 8.3%, P < 0.05). CONCLUSION: We concluded that a significant number of RVV is associated with atopy. Although the exact mechanism(s) of this relationship remains to be investigated atopy might be a causative and/or contributing factor in the pathogenesis of RVV.  相似文献   
14.
1,4-Dioxane is a carcinogenic, non-biodegradable, organic water pollutant which is used as a solvent in various industries. It is also formed as an undesired by-product in the cosmetic and pharmaceutical industry. Given its carcinogenicity and ability to pollute, it is desirable to develop a sensitive and selective sensor to detect it in drinking water and other water bodies. Current works on this sensor are very few and involve complex metal oxide composite systems. A sensitive electrochemical sensor for 1,4-dioxane was developed by modifying a glassy carbon electrode (GCE) with a reduced graphene oxide–curcumin (rGO–CM) nanocomposite synthesized by a simple solution approach. The prepared rGO–CM was characterized by X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR) Spectroscopy, Raman spectroscopy, UV-Vis spectroscopy, and Scanning Electron Microscopy (SEM). The rGO–CM/GCE sensor was employed for the detection of 1,4-dioxane in the range of 0.1–100 μM. Although, the detection range is narrower compared to reported literature, the sensitivity obtained for the proposed sensor is far superior. Moreover, the limit of detection (0.13 μM) is lower than the dioxane detection target defined by the World Health Organization (0.56 μM). The proposed rGO–CM/GCE also showed excellent stability and good recovery values in real sample (tap water and drinking water) analysis.

Reduced graphene oxide–curcumin (rGO–CM) nanocomposite was prepared from graphite oxide using curcumin. The rGO–CM/GCE was used for highly sensitive 1,4-dioxane detection. The LOD obtained (0.13 μM) was lower than the WHO guideline value.  相似文献   
15.
We studied several steps of methionine metabolism in isolated rat hepatocytes both with and without the presence of a hepatotoxic agent (D-galactosamine). By use of selective labelling either on methyl or on carboxyl groups, we showed that intracellular methionine is used preferentially for the methylation of phospholipids (42%) and nucleic acids (31%) via S-adenosylmethionine. In the presence of D-galactosamine, the incorporation of L-(14CH3) methionine into macromolecules is significantly inhibited (greater than 50%). This inhibition is associated with a decrease of S-adenosylmethionine and an increase of methionine in the injured cells. These results suggest that hepatotoxicity of galactosamine may be due in part to an inhibition of the methylation of nucleic acids and phospholipids. Consequently, we hypothesize that hypermethioninemia associated with human liver disease could be due, at least partly, to a defect in synthesis and/or utilization of S-adenosylmethionine by hepatocytes.  相似文献   
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Auditory cortices are interconnected to each other by fibers passing through the corpus callosum (CC). In totally deaf persons no auditory impulses are conveyed to the auditory cortices, hence the auditory pathways become nonfunctional. It was reported that there has been cross-modal plasticity between auditory, visual, and somatosensory cortices. In this study, our aim was to make a comparison in the CC morphometry in hearing subjects and in a selected group in which the auditory system was deprived before the age of 2. 18 deaf and 18 hearing male, handedness matched volunteers, ages varying between 28 and 56 years old were examined. Audiometrical tests were applied to both groups and then T1-weighted midsagittal MR images were obtained. Certain dimensions and areas were measured on these images. There were no statistically significant difference between deaf and hearing subjects, either when dimensions and areas were analyzed by multivariate analysis of variance or when areas were analyzed by univariate analysis of variance. Absence of any significant morphometric difference in the CC of deaf subjects could be thought as an evidence of reflection of functional cortical plasticity.  相似文献   
18.

Background

The aim of this study was to assess the long-term efficacy of stem cell transplantation with revascularization for patients with ischemic cardiomyopathy.

Methods

We enrolled 17 patients with ischemic cardiomyopathy who had undergone autologous stem cell treatment. To assess myocardial ischemia and viability they underwent coronary angiography, stress tests with dobutamine, echocardiography, and positron emission tomography. Peripheral stem cells mobilized using granulocyte colony-stimulating factor (G-CSF) were collected by aphseresis for transplantation transmyocardially into the areas of injury during coronary artery bypass surgery to increase blood flow to the engrafted areas.

Results

Three patients died in the early follow-up period and 4 patients with cardiac failure died during mid-term follow-up; they all underwent stem cell transplantation at 6 months after acute myocardial infarction. The mean follow-up period of the remaining 10 patients was 85.8 ± 9.2 months (range, 70-100). Mean left ventricular ejection fraction improved to 30.0 ± 6.7, whereas the preoperative mean left ventricular ejection fraction of the surviving patients was 25.6 ± 4.5 (P = .035). Mean New York Heart Association (NYHA) functional class decreased from 3.2 to 1.5 (P = .006). When the study population was divided into 2 subgroups according to the interval between acute myocardial infraction and surgery, the patients who underwent autologous stem cell transplantation within the first 6 months after myocardial infraction (Group 1) showed significantly lower NYHA scores at the last follow-up (P = .024 in Group 1 and P = .102 in Group 2). No side effects were observed to be due to the stem cell or G-CSF injections.

Conclusion

Treatment of ischemic cardiomyopathy with autologous stem cell transplantation is easy and safe, opening a new window in the treatment of “no hope” patients.  相似文献   
19.
Single‐antigen bead (SAB) testing permits reassessment of immunologic risk for kidney transplantation. Traditionally, high panel reactive antibody (PRA), retransplant and deceased donor (DD) grafts have been associated with increased risk. We hypothesized that this risk was likely mediated by (unrecognized) donor‐specific antibody (DSA). We grouped 587 kidney transplants using clinical history and single‐antigen bead (SAB) testing of day of transplant serum as (1) unsensitized; PRA = 0 (n = 178), (2) third‐party sensitized; no DSA (n = 363) or (3) donor sensitized; with DSA (n = 46), and studied rejection rates, death‐censored graft survival (DCGS) and risk factors for rejection. Antibody‐mediated rejection (AMR) rates were increased with DSA (p < 0.0001), but not with panel reactive antibody (PRA) in the absence of DSA. Cell‐mediated rejection (CMR) rates were increased with DSA (p < 0.005); with a trend to increased rates when PRA>0 in the absence of DSA (p = 0.08). Multivariate analyses showed risk factors for AMR were DSA, worse HLA matching, and female gender; for CMR: DSA, PRA>0 and worse HLA matching. AMR and CMR were associated with decreased DCGS. The presence of DSA is an important predictor of rejection risk, in contrast to traditional risk factors. Further development of immunosuppressive protocols will be facilitated by stratification of rejection risk by donor sensitization.  相似文献   
20.

Purpose

Our objective was to assess the accuracy of computed tomographic virtual cystoscopy (CTVC) in the detection of urinary bladder lesions.

Methods

Twenty-five patients were examined using CTVC. Bladder scanned using multislice CT at a slice thickness of 1 mm. The data were transferred to a workstation for interactive navigation using surface rendering. Findings obtained from CTVC were compared with results from conventional cystoscopy and with pathological findings.

Results

Thirty-eight lesions were identified. The smallest was 0.2 × 0.3 cm; the largest was 7 × 4.5 cm. Both CTVC and conventional cystoscopy were used. Conventional cystoscopy detected the same number of lesions that were detected by CTVC. On morphological examination, 26 of the lesions were polypoid, 7 were sessile and 5 were bladder wall-thickening. While one of the polypoid lesions was reported as an inverted papilloma, 2 of the 5 lesions that were identified as wall-thickening were malignant and 3 were benign. The sensitivity of using CTVC to identify neoplasias was 100%; the accuracy was 89%.

Conclusion

Although the definitive diagnosis of some suspected urinary bladder tumours is only possible with conventional cystoscopy and biopsy, CTVC is a minimally invasive technique which provides beneficial information about urinary bladder lesions.  相似文献   
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