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81.
Objective
The aim of this study was to investigate the effect of dentin dryness on the variation in the probed nano-scale adhesion force between an AFM silicon nitride tip and demineralized intertubular dentin collagen fibrils network surface.Methods
Dentin specimens were etched with 37% phosphoric acid for 15 s and then divided into three groups. Specimens of the first two groups were air-dried for 5 or 10 s (DH5s and DH10s), respectively, whereas specimens of the third group were left in the hydrated condition (H). For each group, Force curves were characterized by contact-mode AFM and the adhesion force (Fad) was calculated. The structure of the demineralized collagen fibrils network was characterized by tapping mode AFM. The tensile bond strength (TBS) to dentin was evaluated using one alcohol-based dentin self-priming adhesive. The dentin/resin interface was investigated by SEM.Results
Dentin specimens in the wet-hydrated condition (H) showed significantly higher adhesion force and TBS values than dry-dehydrated specimens (DH5s and DH10s). AFM images showed open collagen fibrils network structure in wet-hydrated specimens (H), while the dry-dehydrated specimens (DH5s and DH10s) showed a collapsed appearance to varying degrees. SEM images revealed minimum resin infiltration in dry-dehydrated specimens.Significance
The nano-scale adhesion force between the AFM probe and demineralized intertubular dentin surface was shown to be sensitive to surface air-drying. The decrease in the nano-scale adhesion force with the increase in the time of air-dryness is related to dehydration of the demineralized collagen fibrils network surface. 相似文献82.
Amr M. Salaheldin Abdelhamid 《Archives of gynecology and obstetrics》2013,288(3):673-678
Objective
The aim of this work was to compare the pregnancy rates during IUI cycles with or without endometrial sampling.Study design
A prospective, randomized study.Patients and methods
150 patients were recruited. They were classified into three groups. Each comprised 50 patients. Group 1 was considered the control group and underwent IUI with no endometrial sampling. Group 2 underwent Tao Brush endometrial sampling on day 8–9 of the uterine cycle that preceded the stimulation cycle, and finally, Group 3 underwent Tao Brush endometrial sampling on day 8–9 of the same IUI cycleOutcome of the study
A positive pregnancy test.Results
Pregnancy percentages were 18, 38, and 36 % for group 1, group 2, and group 3, respectively. The paired t test was used to compare each two individual group means. The results show a highly significant value for the paired t test of the control group and group 2 of the patients (p = 0.001), as well as a highly significant results (p = 0.002) for the group 3 and the control group. No significant value was present between the group 2 and 3 of patients (p = 0.322).Conclusion
Endometrial sampling significantly increases pregnancy rates in IUI procedures when it is done in the proliferative phase of the IUI cycle, or the cycle prior to IUI, than pregnancy rates with IUI alone. 相似文献83.
Powell Perng Wei Perng Twalib Ngoma Crispin Kahesa Julius Mwaiselage Sofia D. Merajver Amr S. Soliman 《International journal of gynaecology and obstetrics》2013
Objective
To investigate promoters and barriers for cervical cancer screening in rural Tanzania.Methods
We interviewed 300 women of reproductive age living in Kiwangwa village, Tanzania. The odds of attending a free, 2-day screening service were compared with sociodemographic variables, lifestyle factors, and knowledge and attitudes surrounding cervical cancer using multivariable logistic regression.Results
Compared with women who did not attend the screening service (n = 195), women who attended (n = 105) were older (OR 4.29; 95% CI, 1.61–11.48, age 40–49 years versus 20–29 years), listened regularly to the radio (OR 24.76; 95% CI, 11.49–53.33, listened to radio 1–3 times per week versus not at all), had a poorer quality of life (OR 4.91; CI, 1.96–12.32, lowest versus highest score), had faced cost barriers to obtaining health care in the preceding year (OR 2.24; 95% CI, 1.11–4.53, yes versus no), and held a more positive attitude toward cervical cancer screening (OR 4.64; 95% CI, 1.39–15.55, least versus most averse).Conclusion
Efforts aimed at improving screening rates in rural Tanzania need to address both structural and individual-level barriers, including knowledge and awareness of cervical cancer prevention, cost barriers to care, and access to health information. 相似文献84.
Yasser Ibrahim Orief Mohamed Mourad Alabd Yasser Saad Alkasar Amr Gamil Koritam Akram Deghedy 《Middle East Fertility Society Journal》2013,18(4):278-283
ObjectiveThe aim of the study is to correlate the changes in the biochemical marker MMP-2 in the culture media with the outcome of normogonadotrophic cases undergoing ICSI.MethodologyA prospective study of infertile females was conducted in El-Shatby Maternity University Hospital between October 2011 and May 2012 utilizing a sample of 40 normogonadotrophic infertile women (22 females with unexplained infertility and 18 females with tubal factor infertility).ResultsClinical pregnancy was 57.5%; 15 out of the 22 females with unexplained infertility and 8 out of the 18 females with tubal factor infertility. There was no abortion, ectopic or chemical pregnancy. Ongoing pregnancy after 14 weeks of gestational age was 100%.Total (MMP-2) ranged between (4.1 and 21.1) and (3.5–37) ng/ml with the mean of (9.91 ± 5.48) and (13.91 ± 8.87) ng/ml for non pregnant and pregnant groups respectively. There were no statistical significant differences between the two groups regarding total MMP-2 (P = 0.055).The mean of MMP-2/embryo/h ranged between (0.05 ± 0.05) and (0.06 ± 0.08) ng/ml/embryo/h for non pregnant and pregnant groups respectively. There were no statistical significant differences between the two groups regarding MMP-2/embryo/h (P = 0.234).ConclusionsMMP-2 concentration in the culture media cannot be used as a biochemical marker for embryo selection or prediction of implantation in the normogonadotrophic cases undergoing ICSI.RecommendationsResults of the present study suggest searching for other markers in the culture media for better embryo selection and for prediction of implantation in the normogonadotrophic cases undergoing ICSI. 相似文献
85.
Omar Malik Sherif Saleh Belal Suleiman Bilal Ashqar Amita Maibam Maria Yaseen Amro Elrefaei Abigail Hines Virgilius Cornea Amr El-Husseini Xiaonan Mei Roberto Gedaly Ana Lia Castellanos Thomas Waid 《Transplantation proceedings》2019,51(6):1801-1809
BK viremia (BKV) is a recognized and potentially serious problem in renal transplantation. The risk factors and the impact of BKV on renal allograft and patient survival are controversial. This study reports an 8-year, single-center experience on the prevalence, risk factors, and outcomes of BKV in kidney transplant recipients. This is a retrospective analysis of all patients who received a kidney transplant at the University of Kentucky and had BK viral titers available from 2009 to 2017. BKV was defined by a polymerase chain reaction viral load of ≥ 10,000 copies per mL. Demographic, clinical, and laboratory data generated during routine outpatient follow up and inpatients records were collected. Independent risk factors for BKV were determined using uni- and multivariate analysis. Graft and patient survival was compared using Kaplan-Meier analysis, and the severity of polyomavirus nephropathy on biopsy was scored using the Banff 2017 classification. We identified 122 BK positive (19%) and 527 BK negative (81%) patients. BKV developed after a median of 115 days (range, 80–249 days) following kidney transplantation. The 1-, 5-, and 10-year graft survival was 97%, 75%, and 33% in the BKV group and 96%, 85%, and 71% in the BK negative group, respectively. Likewise, the 1-, 5-, and 10-year patient survival was 98%, 84%, and 52% in the BKV group and 98%, 92%, and 84% in the BK negative group. Male sex, age at transplantation, maintenance steroids, and alemtuzumab induction were associated with developing BKV in the multivariate analysis. We concluded that BKV is not uncommon after renal transplantation. The determinants for BKV are male sex, older transplant recipients, and maintenance steroids. BKV adversely affected graft and patient survival. A unified approach for BKV and polyomavirus nephropathy treatment is needed. 相似文献
86.
Amr Abdelhamid AbouZeid Sherif Elhussiny Ibrahim Shaimaa Abdelsattar Mohammad Ahmed Bassiouny Radwan Mohamed Eldebeiky Ahmed Medhat Zaki 《Journal of pediatric surgery》2019,54(3):471-478
Purpose
To identify anatomical aberrations following PSARP procedure by using MRI, while correlating MRI findings to clinical outcome.Patients and methods
Between January 2014 and December 2017, we conducted our study on male patients with rectourethral fistula who underwent PSARP. Postoperative pelvic MRI studies were performed and correlated to their clinical continence scores (Rintala, and Krickenbeck classification).Results
The study included 31 patients. Fourteen patients were retrieved from the hospital records and accepted to participate in the study; while the remaining 17 were collected from the fecal incontinence clinic. Their age ranged from 40 to 156?months (mean 83) We divided patients in the study into two groups according to their Rintala continence scores: (Group A) 15 patients with low scores (10 or less); and (Group B) 16 patients with higher scores (more than 10). We detected wider pelvic hiatus (hiatus/PC ratio) and more obtuse anorectal angle in group A than B.Conclusion
Several anatomical alterations can be detected by MRI following the PSARP procedure that include abnormalities in the striated muscle sphincter (attenuation/deficiency), deviated neorectum, and presence of excessive perirectal fat. A widened pelvic hiatus and/or obtuse anorectal angle may correlate with poor fecal continence in these patients.Level of Evidence
This is a case control study (level III evidence). 相似文献87.
88.
89.
Aim:To evaluate the protective effects of Hibiscus sabdariffa(Roselle)and Zingiber officinale(Ginger)againstcisplatin-induced reproductive toxicity in rats and to study the mechanisms underlying these effects.Methods:Ethanol extracts of H.sabdariffa or Z.o fficinale[1g/(kg.day)]were given p.o.to male albino rats for 26 days,which began 21 days before a single cisplatin i.p.injection(10 mg/kg body weight).Results:Extracts of H.sabdariffaand Z.officinale reduced the extent of cisplatin-induced sperm abnormality and enhanced sperm motility.Bothextracts restored the control level of malondialdehyde(MDA)(lipid peroxidation marker)in the cisplatin-treated testis.The cisplatin injection induced decline in the levels of superoxide dismutase(SOD),reduced glutathione(GSH)andcatalase(CAT)were significantly reversed to control levels in groups where cisplatin was preceded by the administra-tion of either H.sabdariffa or Z.officinale.Conclusion:Both H.sabdariffa and Z.officinale treatment increasedthe activities of testicular antioxidant enzymes and restored sperm motility of cisplatin-treated rats.The protectiveeffects of tested plants are,therefore,suggested to be mediated by their potent antioxidant activities.(Asian J Androl2006 Sep;8:607-612) 相似文献
90.