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21.
Tatjana A. Nazir 《Cognitive neuropsychology》2013,30(1):73-80
Introduction Due to structural characteristics of the visual pathways, stimuli that are presented in the right half of the visual field (RVF) are initially projected to the left cerebral hemisphere, while those presented in the left half of the visual field (LVF) are projected to the right cerebral hemisphere. This anatomical feature has frequently been taken to support the notion that the well-documented RVF advantage in recognising printed words is a reflection of functional differences between the two hemispheres; notably that of the dominance of the left hemisphere for processing language. Word stimuli that are sent straight to the left hemisphere are believed to profit from more efficient processing than those sent initially to the right hemisphere, because the latter stimuli must follow a longer and more noisy pathway before reaching the language-dominant hemisphere. In the work by Jordan, Patching, and Thomas (2003) the above notion is further developed to speculate that the point of entry of visual information into the cortex may determine the procedure that will underlie the ensuing word recognition process: "... the left hemisphere can process words by mapping orthographic information in parallel onto lexical entries whereas the right hemisphere has a more rudimentary process, that can only map orthographic information sequentially" (p. 50). 相似文献
22.
Herein, we developed a novel homogeneous liquid–liquid microextraction based on liquid nitrogen-induced phase separation (HLLME-LNPS) for the extraction and determination of lead (Pb) in Pb-adulterated opium and refined opium by GFAAS analysis. In this procedure, first, 400 μl of acetonitrile (extractant) containing 7.0 μl of diethyl dithiophosphoric acid (DDTP) is injected into a sample solution and a homogeneous solution is formed. Subsequently, the homogeneous mixture is cooled using liquid nitrogen for 16 seconds. By this process, due to the difference in the freezing points of the organic and aqueous phases, the homogeneous state is broken and the Pb-DDTP species are extracted into the liquid organic phase collected on top of the frozen aqueous phase. The introduced method exhibited a good linearity with a coefficient of determination (r2) of 0.9988 and an acceptable linear range of 0.6–100 μg l−1. Accordingly, the detection limit was 0.2 μg l−1 (S/N = 3) for Pb ions, and a high enrichment factor was obtained. The proposed method was successfully utilized to determine trace levels of Pb in opium samples. The results of the sample analysis showed that 65% of the opium samples and 85% of the refined opium samples had much higher than expected levels of contaminating Pb, and this contamination poses a serious threat to drug users.Herein, we developed a novel homogeneous liquid–liquid microextraction based on liquid nitrogen-induced phase separation (HLLME-LNPS) for the extraction and determination of lead (Pb) in Pb-adulterated opium and refined opium by GFAAS analysis. 相似文献
23.
Intertechnique agreement and interstudy reproducibility of strain and diastolic strain rate at 1.5 and 3 tesla: A comparison of feature‐tracking and tagging in patients with aortic stenosis
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Anvesha Singh MBChB Christopher D. Steadman MBChB MD Jamal N. Khan MBChB BMedSci Mark A. Horsfield PhD Soliana Bekele BSc Sheraz A. Nazir MBChB Prathap Kanagala MBChB Nicholas G.D. Masca MSc Patrick Clarysse PhD Gerry P. McCann MBChB MD 《Journal of magnetic resonance imaging : JMRI》2015,41(4):1129-1137
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25.
Mohammed S. Al-Marhoon Allal Ouhtit Aisha O. Al-Abri Krishna P. Venkiteswaran Qassim Al-Busaidi Josephkunju Mathew Ibrahim Al-Haddabi Omar Shareef Shahid Aquil Khalid Rahman Intisar Al-Hashmi Ishita Gupta Shyam S. Ganguly 《Current Urology》2015,8(3):138-143
Objectives
To determine whether Helicobacter pylori (H. pylori) is detectable in both benign prostatic hyperplasia (BPH) and prostate cancer (PCa). Epidemiological studies have shown significant associations between infective chronic prostatitis and prostatic carcinoma. Many bacteria have been found in the prostate of patients with chronic prostatitis, BPH, and PCa.Methods
One hundred consecutive patients with prostate diseases were enrolled in the study. Detection of H. pylori DNA in prostate tissue from patients with BPH and PCa was performed using both immunohistochemistry and PCR, and the results were confirmed by DNA sequencing. Odds ratios and the Fisher Exact test were used for the analysis of the associations between the variables.Results
Among the patients, 78% had BPH and 19% had PCa. While immunohistochemistry showed no positive sample for H. pylori, PCR combined with sequencing detected H. pylori DNA in prostate tissue samples from 5 patients. However, statistical analysis of the data showed that BPH and PCa are not significantly associated with the presence of H. pylori DNA in prostate tissue (odds ratio = 0.94, 95% confidence interval = 0.09–23.34, one-tailed Chi-square value = 0.660, p > 0.05). The limitation of this study was the small number of PCa patients.Conclusions
This study provides, for the first time, molecular evidence of the presence of H. pylori DNA in prostatic tissue of patients with BPH and PCa. It paves the way for further comprehensive studies to examine the association of H. pylori infection with BPH and PCa.Key Words: Helicobacter pylori infection, Prostate cancer, Benign prostate hyperplasia, PCR 相似文献26.
目的探讨腹腔镜术后戳孔疝的发生原因及防治策略。方法回顾性分析2009年1月至2014年1月,新疆医科大学第二附属医院腹腔镜术后戳孔疝18例患者的临床资料,总结其发病原因、治疗方法、术后恢复情况及并发症发生率。结果本组资料戳孔疝发生率为0.95%,其中术者因素者占38.9%。18例患者均行开放式前入路腹膜前补片修补术,平均手术时间75 min。术后下床活动平均时间1.5 d,肛门排气时间平均1.5 d;切口甲级愈合率100%;平均住院时间7.5 d。术后脐部异物感1例(5.5%),慢性疼痛2例(11.1%)。随访6~12个月,无复发。结论规避术者因素可降低戳孔疝的发生率。开放式前入路腹膜前补片无张力修补术是腹腔镜术后戳孔疝的有效治疗方法,术后恢复快,并发症低是该治疗方法的优势,值得临床推广。 相似文献
27.
Ahmed S. BaHammam Suhail S. Alassiri Aisha H. Al-Adab Ibrahim M. Alsadhan Abdullah M. Altheyab Abdalla H. Alrayes Mohammad M. Alkhawajah Awad H. Olaish 《Saudi medical journal》2015,36(8):911-919
Objectives:
To evaluate continuous positive airway pressure (CPAP) compliance and define predictors of CPAP compliance among Saudi patients with obstructive sleep apnea (OSA) after applying an educational program.Methods:
This prospective cohort study included consecutive patients diagnosed to have OSA based on polysomnography between January 2012 and January 2014 in King Saud University, Riyadh, Kingdom of Saudi Arabia. All patients had educational sessions on OSA and CPAP therapy before sleep study, and formal hands-on training on CPAP machines on day one, day 7, and day 14 after diagnosis. The follow-up in the clinic was carried out at one, 4, and 10 months after initiating CPAP therapy. Continuous positive airway pressure compliance was assessed objectively. Logistic regression model was used to assess the predictors of CPAP adherence.Results:
The study comprised 156 patients with a mean age of 51.9±12.1 years, body mass index of 38.4±10.6 kg/m2, and apnea hypopnea index of 63.7±39.3 events/hour. All patients were using CPAP at month one, 89.7% at month 4, and 83% at month 10. The persistence of CPAP-related side effects and comorbid bronchial asthma remained as independent predictors of CPAP compliance at the end of the study.Conclusion:
With intensive education, support, and close monitoring, more than 80% of Saudi patients with OSA continued to use CPAP after 10 months of initiating CPAP therapy.Continuous positive airway pressure (CPAP) is a standard, safe, and efficacious treatment for obstructive sleep apnea (OSA), a common disorder with established harm to quality of life and adverse consequences for cardiovascular health.1 Obstructive sleep apnea is characterized by recurrent partial (hypopnea) or complete (apnea) upper airway obstruction during sleep. These recurrent respiratory events usually cause intermittent hypoxemia and sleep fragmentation.2 Recent data demonstrated that the estimated prevalence of moderate to severe OSA ranges from 10-17% in middle-aged and elderly men.3 In Saudi Arabia, 3 out of 10 middle-aged Saudi men and 4 out of 10 middle-aged Saudi women are at high risk of having OSA.4,5 The mainstay medical treatment for OSA is CPAP therapy.6 Among various available therapeutic modalities for OSA, CPAP remains the most effective treatment.6 Continuous positive airway pressure is a machine that applies positive airway pressure to the upper air passages via a mask fitted on the mouth or nose to keep the throat open.6 Previous studies in Western countries showed that OSA patients on CPAP therapy use their machines on average from 4.5 to 5.5 hours per night with compliance rates ranging from 30-85%.7,8 Several studies have been conducted to define factors that influence, or predict CPAP use and adherence, and reported conflicting results.6 Moreover, several studies reported that race might influence CPAP adherence. For example, available data suggest lower CPAP adherence among African Americans than Caucasians.9 An earlier study that assessed CPAP compliance subjectively (self-reports) among Saudi patients with OSA after 3 months of initiation of CPAP therapy revealed an overall compliance rate of 39%.10 However, self-reports have been shown to overestimate CPAP use by approximately one hour/night when compared with objectively measured CPAP use.11 In general, there are very few data on objectively assessed long-term CPAP compliance in the literature. Moreover, there is a lack of previous study objectively addressing the rate of CPAP compliance, the predictors of good compliance, and the side effects of CPAP treatment in Saudi OSA patients. Therefore, we established in our center an educational program for patients with OSA and easily accessible medical support, and close follow-up of CPAP compliance. This study was conducted to evaluate CPAP compliance and to define predictors of CPAP compliance among Saudi patients with OSA after applying the new educational program. 相似文献28.
29.
30.
Yue-Hong Tao Nazir Sharif Bi-He Zeng Yan-Yan Cai Yu-Xiu Guo 《International journal of clinical and experimental pathology》2015,8(10):12564-12570
Background: Central precocious puberty (CPP) is characterized as increasing gonadotropin-releasing hormone (GnRH) release. Orexin-A has also been shown to affect GnRH release. However, there are few reports about the effect of orexin A on the treatment of CPP. Methods: After establishing the precocious puberty model, the rats were divided into four groups: normal control, precocious puberty rats, precocious puberty rats treated with normal saline and precocious puberty rats treated with orexin-A. The vaginal opening time, second estrus cycle, ovarian index and uterus index of rats in each group were detected. qRT-PCR was performed to examine the expression of MEG3 and kisspeptin in rats. HT22 cells were transfected with pcDNA-MEG3 to detect the expression of Kisspeptin. Results: In this study, we found that orexin-A not only delayed the day of vaginal opening and regular estrus cycle days but also decreased the ovarian index and uterus index in rats with CPP. In addition, orexin-A reversed the up-regulation of MEG3 and kisspeptin in rats with CPP. In HT22 cells, the mRNA and protein level of kisspeptin were enhanced by pcDNA-MEG3. Conclusion: Our results suggest that orexin-A ameliorates central precocious puberty in rat and MEG3 might be involved in this effect, suggesting that MEG3 might be a novel target in treating central precocious puberty. 相似文献