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11.
H Tahira 《Canadian Metallurgical Quarterly》1976,52(2):125-137
The renin-angiotensin system, potassium and adrenocorticotropin (ACTH) are well known as control mechanism for aldosterone secretion. However, the precise mechanism of these factors for aldosterone secretion remain still unclear. Several interesting evidences related to the effects of Coenzyme Q on the secretion and biosynthesis of aldosterone have been demonstrated. Biochemical action of Coenzyme Q is generally accepted as a component of the electron transfer process of respiration in mitochondria. Fabre et al demonstrated that significant reduction of plasma aldosterone concentration in adrenal venous by the Coenzyme Q infusion. Weinstein et al observed that urine sodium excretion decreased after infusion of Coenzyme Q into renal artery. Kumagai et al suggested that Coenzyme Q inhibited the activity of 18-hydroxylase in the adrenal cortex. The present study was designed to evaluate the effects of Coenzyme Q on the secretion of aldosterone. Method: 24 cases of male among el and beagle dogs were subdivided into 4 groups. 1st group were administered intravenous infusion of Coenzyme Q, 2nd group were orally administered Coenzyme Q for 7 weeks, 3rd group were administered simultaneous infusion of Coenzyme Q and angiotensin II and 4th group were administered furosemide orally under the condition of continuous Coenzyme Q administration. Then, plasma concentrations of aldosterone, 11-OHCS and angiotensin I were determined during the time course. Results and Discussions: Plasma aldosterone concentration was significantly increased after intravenous infusion of angiotensin II and decreased 45 minutes after the beginning of infusion. However, the concentration still remained higher than control level. By the simultaneous infusion of Coenzyme Q with angiotensin II, the decreased concentration again increased significantly. It seems that above mentioned results suggest possibility that Coenzyme Q potentiate the action of angiotensin II on aldosterone secretion. By the intravenous infusion of Coenzyme Q, plasma aldosterone concentration increased significantly and concentrations of plasma 11-OHCS and angiotensin I did not affected. This result suggests that Coenzyme Q may stimulate aldosterone secretion from adrenal cortex without increase of ACTH and renin-angiotensin. 4 hours after the oral administration of Coenzyme Q, plasma aldosterone concentration was increased significantly. Na/K in 24 hours' excreta was decreased by Coenzyme Q administration. The decrease of Na/K in excreta may be reflection of the increase of aldosterone secretion. Although, plasma aldosterone concentration increased for the short duration by the Coenzyme Q, it decreased gradually and returned to the control level after 7 days under the condition of continuous oral administration. By the oral administration of furosemide under prolonged Coenzyme Q administration plasma aldosterone concentration increased significantly and remained higher than that of control. 相似文献
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Marrium Anam Vasaki a/p Ponnusamy Muzammil Hussain Muhammad Waqas Nadeem Mazhar Javed Hock Guan Goh Sadia Qadeer 《计算机、材料和连续体(英文)》2021,67(1):89-105
Trabecular bone holds the utmost importance due to its significance regarding early bone loss. Diseases like osteoporosis greatly affect the structure of the Trabecular bone which results in different outcomes like high risk of fracture. The objective of this paper is to inspect the characteristics of the Trabecular Bone by using the Magnetic Resonance Imaging (MRI) technique. These characteristics prove to be quite helpful in studying different studies related to Trabecular bone such as osteoporosis. The things that were considered before the selection of the articles for the systematic review were language, research field, and electronic sources. Only those articles written in the English language were selected as it is the most prominent language used in scientific, engineering, computer science, and biomedical researches. This literature review was conducted on the articles published between 2006 and 2020. A total of 62 research papers out of 1050 papers were extracted which were according to our topic of review after screening abstract and article content for the title and abstract screening. The findings from those researches were compiled at the end of the result section. This systematic literature review presents a comprehensive report on scientific researches and studies that have been done in the medical area concerning trabecular bone. 相似文献
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Classification is one of the most important tasks in machine learning with a huge number of real-life applications. In many practical classification problems, the available information for making object classification is partial or incomplete because some attribute values can be missing due to various reasons. These missing values can significantly affect the efficacy of the classification model. So it is crucial to develop effective techniques to impute these missing values. A number of methods have been introduced for solving classification problem with missing values. However they have various problems. So, we introduce an effective method for imputing missing values using the correlation among the attributes. Other methods which consider correlation for imputing missing values works better either for categorical or numeric data, or designed for a particular application only. Moreover they will not work if all the records have at least one missing attribute. Our method, Model based Missing value Imputation using Correlation (MMIC), can effectively impute both categorical and numeric data. It uses an effective model based technique for filling the missing values attribute wise and reusing then effectively using the model. Extensive performance analyzes show that our proposed approach achieves high performance in imputing missing values and thus increases the efficacy of the classifier. The experimental results also show that our method outperforms various existing methods for handling missing data in classification. 相似文献
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Muzammil Hussain A.A. Zaidan B.B. Zidan S. Iqbal M.M. Ahmed O.S. Albahri A.S. Albahri 《Telematics and Informatics》2018,35(5):1335-1354
Mobile Health (mHealth) applications are readily accessible to the average user of mobile devices, and despite the potential of mHealth applications to improve the availability, affordability and effectiveness of delivering healthcare services, they handle sensitive medical data, and as such, have also the potential to carry substantial risks to the security and privacy of their users. Developers of applications are usually unknown, and users are unaware of how their data are being managed and used. This is combined with the emergence of new threats due to the deficiency in mobile applications development or the design ambiguities of the current mobile operating systems. A number of mobile operating systems are available in the market, but the Android platform has gained the topmost popularity. However, Android security model is short of completely ensuring the privacy and security of users’ data, including the data of mHealth applications. Despite the security mechanisms provided by Android such as permissions and sandboxing, mHealth applications are still plagued by serious privacy and security issues. These security issues need to be addressed in order to improve the acceptance of mHealth applications among users and the efficacy of mHealth applications in the healthcare systems. Thus, this paper presents a conceptual framework to improve the security of medical data associated with Android mHealth applications, as well as to protect the privacy of their users. Based on the literature review that suggested the need for the intended security framework, three-distinct and successive phases are presented, each of which is described in a separate section. First, discussed the design process of the first phase to develop a security framework for mHealth apps to ensure the security and privacy of sensitive medical data. The second phase is discussed who to achieve the implementation of a prototypic proof-of-concept version of the framework. Finally, the third phase ending discussed the evaluation process in terms of effectiveness and efficiency for the proposed framework. 相似文献
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Nadeem R Hanif MA Shaheen F Perveen S Zafar MN Iqbal T 《Journal of hazardous materials》2008,150(2):335-342
The waste distillery sludge from sugar-cane industry was pretreated physically (boiled, heated and autoclaved) as well as chemically (HCl, H(2)SO(4), H(3)PO(4), NaOH, Ca(OH)(2), Al(OH)(3), C(6)H(6), HCHO, CH(3)OH and C1(2)H(25)OSO(3)Na (sodium dodecyl sulphate (SDS)) for assessing the comparative sorption capacity of untreated and modified distillery sludge for Pb(II) biosorption from aqueous solutions. Experiments were conducted in shake flasks on a batch basis to access the effect of different experimental parameters such as pH, biosorbent dosage, biosorbent size, initial Pb(II) concentration and contact time. The uptake capacity 'q' (mg/g) of untreated and pretreated distillery sludge was in following order: NaOH (51.29+/-1.21)>HCl (49.82+/-1.22)>HCHO (49.56+/-1.14)>H(2)SO(4) (47.71+/-1.20)>HgCl(2) (45.32+/-1.06)>Ca(OH)(2) (44.01+/-1.18)>MeOH (43.73+/-1.23)>C(6)H(6) (42.72+/-1.19)>H(3)PO(4) (42.01+/-1.17)>SDS (40.87+/-1.27)>autoclaved (40.23+/-1.24)>Boiled (39.95+/-1.19)>heated (38.87+/-1.32)>Al (OH)(3) (38.30+/-1.14)>untreated (37.76+/-1.21). In further parameter studies, the optimized biosorbent size was 0.250 mm at pH 5 and best dose was 0.05 g of biosorbent. The applicability of the Langmuir and Freundlich models for sorption process was tested and best fitted model was Langmuir with the coefficient of determination (R(2)) value, 0.97, the process followed second order kinetic mechanism. 相似文献
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Arain MA Quetschke V Gleason J Williams LF Rakhmanov M Lee J Cruz RJ Mueller G Tanner DB Reitze DH 《Applied optics》2007,46(12):2153-2165
We describe an adaptive optical system for use as a tunable focusing element. The system provides adaptive beam shaping via controlled thermal lensing in the optical elements. The system is agile, remotely controllable, touch free, and vacuum compatible; it offers a wide dynamic range, aberration-free focal length tuning, and can provide both positive and negative lensing effects. Focusing is obtained through dynamic heating of an optical element by an external pump beam. The system is especially suitable for use in interferometric gravitational wave interferometers employing high laser power, allowing for in situ control of the laser modal properties and compensation for thermal lensing of the primary laser. Using CO(2) laser heating of fused-silica substrates, we demonstrate a focal length variable from infinity to 4.0 m, with a slope of 0.082 diopter/W of absorbed heat. For on-axis operation, no higher-order modes are introduced by the adaptive optical element. Theoretical modeling of the induced optical path change and predicted thermal lens agrees well with measurement. 相似文献
20.
The use of optical interconnects for communication between points on a microchip is motivated by system-level interconnect modeling showing the saturation of metal wire capacity at the global layer. Free-space optical solutions are analyzed for intrachip communication at the global layer. A multiscale solution comprising microlenses, etched compound slope microprisms, and a curved mirror is shown to outperform a single-scale alternative. Microprisms are designed and fabricated and inserted into an optical setup apparatus to experimentally validate the concept. The multiscale free-space system is shown to have the potential to provide the bandwidth density and configuration flexibility required for global communication in future generations of microchips. 相似文献