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991.
Mike Harley Mohammed A Mohammed Shakir Hussain John Yates Abdullah Almasri 《BMJ (Clinical research ed.)》2005,330(7497):929
Objectives To investigate whether routinely collected data from hospital episode statistics could be used to identify the gynaecologist Rodney Ledward, who was suspended in 1966 and was the subject of the Ritchie inquiry into quality and practice within the NHS.Design A mixed scanning approach was used to identify seven variables from hospital episode statistics that were likely to be associated with potentially poor performance. A blinded multivariate analysis was undertaken to determine the distance (known as the Mahalanobis distance) in the seven indicator multidimensional space that each consultant was from the average consultant in each year. The change in Mahalanobis distance over time was also investigated by using a mixed effects model.Setting NHS hospital trusts in two English regions, in the five years from 1991-2 to 1995-6.Population Gynaecology consultants (n = 143) and their hospital episode statistics data.Main outcome measure Whether Ledward was a statistical outlier at the 95% level.Results The proportion of consultants who were outliers in any one year (at the 95% significance level) ranged from 9% to 20%. Ledward appeared as an outlier in three of the five years. Our mixed effects (multi-year) model identified nine high outlier consultants, including Ledward.Conclusion It was possible to identify Ledward as an outlier by using hospital episode statistics data. Although our method found other outlier consultants, we strongly caution that these outliers should not be overinterpreted as indicative of “poor” performance. Instead, a scientific search for a credible explanation should be undertaken, but this was outside the remit of our study. The set of indicators used means that cancer specialists, for example, are likely to have high values for several indicators, and the approach needs to be refined to deal with case mix variation. Even after allowing for that, the interpretation of outlier status is still as yet unclear. Further prospective evaluation of our method is warranted, but our overall approach may be potentially useful in other settings, especially where performance entails several indicator variables. 相似文献
992.
Salem Baldi Qianshi Zhang Zhenyu Zhang Mohammed Safi Hassan Khamgan Han Wu Mengyan Zhang Yuanyuan Qian Yina Gao Abdullah Shopit Abdullah AlDanakh Mohammed Alradhi Murad AlNusaif Yunfei Zuo 《Journal of cellular and molecular medicine》2022,26(24):5984
According to our prior findings, ARID1A expression is decreased in colon cancer, which has a poor prognosis. In this study, we investigated the ARID1A‐VIM/CDH1 signalling axis''s role in colon cancer proliferation and migration. The differentially expressed genes in cells that might be controlled by ARID1A were discovered by a database screening for ARID1A knockout. qPCR was used to analyse ARID1A and EMT markers expression levels in colon cancer. We utilized siRNA RID1A to explore the influence of ARID1A silencing on EMT in CRC cells. The function of ARID1A in the colon was investigated utilizing the wound healing, transwell and CCK‐8 WST‐ assays. The molecular mechanism by which ARID1A regulates VIM and CDH1 was elucidated using chip‐qPCR. Numerous genes involved in EMT were dysregulated in the absence of ARID1A. VIM expression increased in cells lacking ARID1A expression and vice versa. Many COAD samples with high ARID1A mRNA expression had low VIM mRNA expression, despite the relevance. CDH1 gene was positively correlated with ARID1A. Moreover, siRNA‐ARID1A‐transfected cells accelerated cell migration and invasion and increased cell proliferation rate in vitro. Chip‐qPCR analysis showed that ARID1A binds to the promoters of both genes and changes their expression in colon cancer. ARID1A inactivation is associated with VIM activation and CDH1 suppression, which might serve as crucial molecules influencing COAD prognosis, accelerate tumour progression, and shorten patients'' survival time, and promote metastases of COAD. Thus, depletion of ARID1A can be therapeutically exploited by targeting downstream effects to improve cancer treatment‐related outcomes. 相似文献
993.
994.
Ambrin Fatima Jan Hoeber Jens Schuster Eriko Koshimizu Carolina Maya-Gonzalez Boris Keren Cyril Mignot Talia Akram Zafar Ali Satoko Miyatake Junpei Tanigawa Takayoshi Koike Mitsuhiro Kato Yoshiko Murakami Uzma Abdullah Muhammad Akhtar Ali Rein Fadoul Loora Laan Casimiro Castillejo-Lpez Maarika Liik Zhe Jin Bryndis Birnir Naomichi Matsumoto Shahid M. Baig Joakim Klar Niklas Dahl 《American journal of human genetics》2022,109(3):542-546
995.
Hosam Ali Baeshen Fahad F. Alsulaimani Wael Awadh Maram Ahmed Ageeli Shahabe Saquib Abullais Nabeeh Abdullah Alqahtani Mohammad Y. Alshahrani Jagadish Hosmani Shankargouda Patil 《Saudi Journal of Biological Sciences》2022,29(3):1789-1795
BackgroundThis study aimed to examine the cellular components of the gingiva during orthodontic treatment with fixed and removable appliances. The cellular and molecular cues of pathologies of the gingival tissue associated with the use of different orthodontic appliances could be studied.Materials and methodsTissue samples of gingiva were received from healthy patients undergoing gingivectomy for aesthetic purpose and from patients with fixed and removable functional orthodontic appliances undergoing gingivectomy for gingival overgrowth. The collected samples were stored in a sterile container with phosphate-buffered saline and to carry out further processes it was transported to the laboratory.ResultsCells positive for ECAD and NCAD were found to be increased in fixed appliances where as CD90 and CD105 positive cells showed no significant difference in all the three groups. CD24 and CD146 positive cells were increased significantly in removable and fixed than normal whereas CD133 positive cells were decreased in removable and fixed than normal. CD44 positive cells showed no noticeable change in all three groups. The gene expression levels of KRT5, SOX2, NANOG, and CXCL5 were found to be significantly increased in removable and fixed appliance groups. However, KRT8, CXCL10, and TIMP1 were increased only in fixed appliance group but CXCL10 showed decreased expression in removable appliance group. KRT6A, MYC, and MMP9 were decreased in fixed appliance group whereas MYC and MMP9 were increased in removable appliance group. KRT6A, KRT8, and TIMP1 showed no significant difference in removable appliance group.ConclusionThis study demonstrated essential roles of various genes, showing their contribution in regulating cell proliferation and migration in both the removable and fixed functional appliances. 相似文献
996.
Saad Alkahtani Md Saquib Hasnain Hamzah Algamdy Nada H. Aljarba Abdullah AlKahtane 《Saudi Journal of Biological Sciences》2022,29(3):1585-1591
Through the boost of the natural medicinal market, individuals began to use a variety of organic materials in the marketed herbal preparation. Lagerstroemia speciosa (LS) leaves are known as banaba. People have been using a decoction of LS leaves as antidiabetic. The study aimed to investigate the acute and sub-acute oral toxicity of LS in Sprague-Dawley rats. The acute toxicity was determined by a single oral dose of LS (2000 mg/kg). Therein animal behaviour and mortality rate were observed for 14 days. The LS (200 mg/kg) was given for 28 days daily in the sub-acute study. The body weight, organ weight, food, water intake, biochemical, haematological parameters, and histopathology were studied. The findings of this study showed no mortality or morbidity was found in acute and sub-acute toxicity studies in rats.Additionally, no significant variations were found in the respective weight of organ, haematological and biochemical parameters of treated groups with reference to the control group. Moreover, no visible histological changes were detected in the liver of treated groups with reference to the control. In conclusion, the oral administration of LS did not fabricate any major toxic effect in rats. No toxic consequences were reported during acute and sub-acute toxicity investigations. Overall, LS is a safe, natural bio-actives as studied. Further investigations of cytotoxicity and genotoxicity of the above drug(s) or their combinations may be executed for appreciative safety. 相似文献
997.
The present study is concerned with the isolation and screening of different strains of Aspergillus oryzae for the production of alpha amylase. Ninety strains were isolated from soil and tested for the production of alpha amylase in shake flasks. Of all the strains tested, Aspergillus oryzae GCB-32 and Aspergillus oryzae GCB-35 gave maximum production of alpha amylase. Different culture media were screened for the production of alpha amylase by these two strains. M1 medium containing starch, yeast extract, NH4Cl, MgSO4·7H2O and CaCl2 gave the maximum production of alpha amylase by both the strains Aspergillus oryzae GCB-32 and Aspergillus oryzae GCB-35.Kinetic analysis revealed that the values of product yield coefficient(Yp/x) and specific product yield coefficient(qp) were found highly significant(p≤0.05) when medium M1 was used for the enzyme production. 相似文献
998.
Raed Abdullah Alharbi 《Saudi Journal of Biological Sciences》2021,28(6):3594-3601
Coronaviruses have been causing pandemic situations across the globe for the past two decades and the focus is on identifying suitable novel targets for antivirals and vaccine development. SARS-CoV-2 encodes a small hydrophobic envelope (E) protein that mediates envelope formation, budding, replication, and release of progeny viruses from the host. Through this study, the SARS-CoV-2 E protein is studied for its open and closed state and focused in identifying antiviral herbs used in traditional medicine practices for COVID-19 infections. In this study using computational tools, we docked the shortlisted phytochemicals with the envelope protein of the SARS-CoV-2 virus and the results hint that these compounds interact with the pore-lining residues. The molecular level understanding of the open state is considered and the active inhibitors from the phytochemicals of Ayurvedic medicinal plants from Withania somnifera. We have thus identified a potential phytochemical compound that directly binds with the pore region of the E protein and thereby blocks its channel activity. Blocking the ion channel activity of E protein is directly related to the inhibition of virus replication. The study shows encouraging results on the usage of these phytochemicals in the treatment/management of SARS-CoV-2 infection. 相似文献
999.
Abdullah Sener Francine Malaisse-Lagae Christine Gervy-Decoster Willy J. Malaisse 《Cell biochemistry and function》1993,11(2):145-151
In thyroidectomized rats, the activity of FAD-linked glycerophosphate dehydrogenase was severely diminished in liver homogenates but not affected significantly in pancreatic islet homogenates, whilst the activity of 2-ketoglutarate dehydrogenase was decreased modestly in both liver and islet homogenates. Likewise, in intact islets of thyroidectomized rats, the generation of3HOH from [2-3H]glycerol was not decreased, and the ratio between oxidative and total glycolysis not significantly lower than in islets from sham-operated rats, at least in the presence of a high concentration of D-glucose. Nevertheless impaired oxidation of both D-[3,4-14C]glucose and D-[6-14C]glucose was observed in islets of thyroidectomized rats, the relative magnitude of such a decrease being more pronounced at a low than at a high D-glucose concentration. Such metabolic anomalies coincided with a lower level of plasma insulin and a decreased output of insulin by islets incubated at low (2·8 mM ), but not higher, concentrations of D-glucose. It is concluded that hypothyroidism does not mimic the deficiency in islet FAD-linked glycerophosphate dehydrogenase activity found in rats with inherited or acquired non-insulin-dependent diabetes. 相似文献
1000.
Shivam Gupta Goro Yamada Rose Mpembeni Gasto Frumence Jennifer A. Callaghan-Koru Raz Stevenson Neal Brandes Abdullah H. Baqui 《PloS one》2014,9(7)
In Tanzania, the coverage of four or more antenatal care (ANC 4) visits among pregnant women has declined over time. We conducted an exploratory analysis to identify factors associated with utilization of ANC 4 and ANC 4 decline among pregnant women over time. We used data from 8035 women who delivered within two years preceding Tanzania Demographic and Health Surveys conducted in 1999, 2004/05 and 2010. Multivariate logistic regression models were used to examine the association between all potential factors and utilization of ANC 4; and decline in ANC 4 over time. Factors positively associated with ANC 4 utilization were higher quality of services, testing and counseling for HIV during ANC, receiving two or more doses of SP (Sulphadoxine Pyrimethamine)/Fansidar for preventing malaria during ANC and higher educational status of the woman. Negatively associated factors were residing in a zone other than Eastern zone, never married woman, reported long distance to health facility, first ANC visit after four months of pregnancy and woman''s desire to avoid pregnancy. The factors significantly associated with decline in utilization of ANC 4 were: geographic zone and age of the woman at delivery. Strategies to increase ANC 4 utilization should focus on improvement in quality of care, geographic accessibility, early ANC initiation, and services that allow women to avoid pregnancy. The interconnected nature of the Tanzanian Health System is reflected in ANC 4 decline over time where introduction of new programs might have had unintended effects on existing programs. An in-depth assessment of the recent policy change towards Focused Antenatal Care and its implementation across different geographic zones, including its effect on the perception and understanding among women and performance and counseling by health providers can help explain the decline in ANC 4. 相似文献