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The occurrence of oxidative stress during the sperm freeze-thaw cycles affects the sperm parameters and eventually leads to a decrease in its reproductive potential. Sperm protection against oxidative reactions during freezing is done by antioxidants. Since the selection of a suitable sperm cryopreservation bank is effective in maintaining acceptable reproductive potential and motility of sperm during cryopreservation.This study aimed to evaluate the antioxidant effects of different doses of the extract of brown algae Sargassum on oxidative stress and frozen human sperm parameters.We conducted a randomized controlled trial on the semen samples from 11 healthy men in the age group of 25 to 36 years. The samples were collected by masturbation after 3 to 5 days of abstinence from ejaculation. The specimens were divided into 3 equal parts, including 1 control group and 2 experimental groups.The 2 experimental groups were frozen using the rapid solidification technique with Sargassum extract at doses of 250 and 500 μg/mL.Motility and morphology of sperms were measured using a computer system and CASA software and the amount of reactive oxygen species was determined using Oxisperm kit.Sargassum extract significantly decreased the amount of reactive oxygen species (P < 0.005) and at doses of 250 and 500 μg/mL, significantly increased the overall motility (P < 0.006) and progressive motility (P < 0.007) after solidification, but did not affect the normal morphology of sperms.The addition of ethanol extract of Sargassum prevents reactive oxygen species production during the solidification process and improves sperm motility at doses of 250 and 500 μg/mL.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Enduring kidney illness (CKD) is a mounting worldwide issue with respect to people’s health, needing to...  相似文献   
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Annals of Surgical Oncology - The purpose of this study was to define contemporary management recommendations regarding who would benefit from surgical excision of intraductal papilloma (IDP). A...  相似文献   
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Purpose

Oncotype Dx (ODx) is a multigene assay that is prognostic and predictive in estrogen receptor (ER) positive early breast cancer. ODx recurrence score (RS) is reported to be histologic grade dependent. Relationship of RS with breast cancer histologic subtypes is unknown. This study was designed to assess the relationship of histologic subtype with RS. Histologic grade dependence of RS was also investigated.

Methods

Results of consecutive ODx tests (1/2007–7/2016) from two institutions were reviewed. Histologic subtypes (in: Lakhani et al., WHO classification, IARC Press, Lyon, 2012), combined Nottingham histologic grade, age and tumor size were recorded from pathology reports. Univariate and multivariate analysis was performed to investigate the relationship between RS and ODx risk categories and histologic subtypes, grade, age and tumor size.

Results

RS was grade dependent. RS of grade 1 and grade 2 tumors were significantly lower than grade 3 tumors. There was no high-risk grade 1 tumor. In favorable histologic subtypes there was no high-risk tumor. Mean RS of grade 1 lobular tumors was significantly higher than grade 1 ductal tumors. Using newer ODx cut-offs, 5 grade 1 tumors were reclassified as high risk (RS > 25) and grade 3 lobular tumors showed significantly higher rate of reclassification as high-risk than grade 3 ductal tumors. In a multivariate analysis, only grade showed a significant positive correlation with RS. Adding dichotomous histologic subtyping (favorable vs. non-favorable) to grade further improved correlation with RS.

Conclusions

The Oncotype Dx result is impacted by histologic grade and histologic subtype. Tumors with favorable histologic subtypes and histologic grade 1 tumors do not have high-risk RS. High RS in a grade 1 tumor or in a tumor with favorable histology is unusual that warrants further investigation. Invasive lobular carcinomas rarely show high-risk RS. Histologic grade and histologic subtype should be considered while ordering ODx testing.
  相似文献   
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PurposeType 2 diabetes mellitus (T2DM) is the subject of numerous randomized controlled trials (RCTs). The validity of RCTs may be threatened by attrition bias due to the discontinuation of the study. The aim of this systematic review is to evaluate the reasons of patient’s withdrawal from these RCTs.MethodsA systematic literature search on PubMed, Cochrane Library, Web of Science, and Scopus databases was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram. The aim was to obtain all relevant blinded RCTs published before January 2017 in which the effectiveness of synthetic drugs, vitamins/minerals were compared to that of placebo or active control in T2DM. The quality of RCTs was assessed using the Jadad score. The frequency of withdrawal reasons was presented based on treatments with placebo/active control, national/international level of the studies, and publication year. Meta-analysis was not performed due to the heterogeneity.ResultsOverall, 1368 articles comprising of 640,780 subjects were included. In the majority of the RCTs (75.0%), the intervention and the placebo arms were compared. Most of the included studies (96%) were classified in the high-quality category (Jadad score≥3). The highest proportion of reported withdrawal cases was found in international studies, national RCTs conducted in Japan, and RCTs published in 2011. The withdrawal reasons were reported for 91,669 (63.75%) of the total 143,794 participants who had withdrawn from these studies. The main reported reasons were “adverse effects” (24.04%), “withdraw consent” (16.10%), and “missing data” (11.08%). Variations in the reported withdrawal reasons were based on the country or published year. RCTs with triple blinded design as well as those in which anti-hyperlipidemia and anti-obesity medications were applied, showed significantly higher probability of reported the withdrawal.ConclusionHigh proportion of reported discontinuation in blinded RCTs on patients with T2DM was related to drug adverse effects. Overall, the total number and reason of drop out were unsatisfactory.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40199-020-00380-7.  相似文献   
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Congenital sternal foramen is an anomaly whose occurrence is rare in human but is especially unusual in animals. This defect was formed when fusion of multiple ossification centers was incomplete. It may be associated with other lesions in body organs especially cardiac anomalies. In the present study, we report a very rare case of congenital sternal foramen in a Holstein calf. The oval defect was like a gunshot wound and located at the lower third of the sternum. Apparently, the rest of skeleton system seems normal. The awareness of the anomaly is important for better diagnosis and treatment of diseases.  相似文献   
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