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111.
112.
M. A. Qadar Pasha R. B. Ram M. D. Gupta 《Indian journal of clinical biochemistry : IJCB》2000,15(1):29-35
Determination of ammonia level in blood is important, especially in the diagnosis of hepatic disorders. An indigenously purified
enzyme was used in the standardisation of the assay. The assay is a two reagent system, requires five minutes for completion
and can be performed at temperature between 25–27°C. Performance of the assay was assessed by linearity, imprecision, functional
sensitivity and interference studies. Lyophilised reagent I and reagent II were found stable for at least one year. The plasma
level of ammonia for the controls was 13.7±7.3 μMol/L, whereas for subjects of hepatic disorders, it was 69.1±32.4 μMol/L
(P<0.001). The functional sensitivity was between 2–1000 μMol/L. Within-run coefficient of variation was between 1.1–2.0%
and between-run coefficient of variation was between 1.9–3.7%. The mean recovery after dilution was 99.6%. The present method
can estimate ammonia up to 1000 μMol/L without dilution of sample. Assay time of five minute may be shortened to one minute.
This method is suited for routine clinical use in treatment of hepatic disorders. 相似文献
113.
Drug discovery is an expensive and lengthy process. Among the different phases, drug discovery and preclinical trials play an important role as only 5–10 of all drugs that begin preclinical tests proceed to clinical trials. Indeed, current high-throughput screening technologies are very expensive, as they are unable to dispense small liquid volumes in an accurate and quick way. Moreover, despite being simple and fast, drug screening assays are usually performed under static conditions, thus failing to recapitulate tissue-specific architecture and biomechanical cues present in vivo even in the case of 3D models. On the contrary, microfluidics might offer a more rapid and cost-effective alternative. Although considered incompatible with high-throughput systems for years, technological advancements have demonstrated how this gap is rapidly reducing. In this Review, we want to further outline the role of microfluidics in high-throughput drug screening applications by looking at the multiple strategies for cell seeding, compartmentalization, continuous flow, stimuli administration (e.g., drug gradients or shear stresses), and single-cell analyses. 相似文献
114.
Paul Sandamas Elena M. Gutierrez-Farewik Anton Arndt 《Journal of sports sciences》2020,38(19):2200-2207
ABSTRACT The aims of this study were (a) to describe the kinematics underlying the phenomenon of the knee of the swing leg passing medially in front of the athlete during the single push (SP) phase of the block sprint start, and (b) to determine the relationships between block phase pelvis range of motion (RoM), 1st step width and block phase performance. Three-dimensional kinematic data (250 Hz) were collected from eleven competitive sprinters (100 m PB: 11.17 ± 0.41) performing maximal effort block starts. The joint angles of the rear hip with respect to the pelvis and the pelvis segment angles with respect to the laboratory coordinate system were calculated during the block start phase to the end of the 1st stance. A combination of pelvis list and rotation (not hip adduction) was coupled with the thigh of the swing leg moving medially during the SP phase. A very high positive correlation was found between pelvic list RoM and 1st step width (r = 0.799, p = 0.003). No other significant correlations were found. Attempting to reduce pelvic RoM or changing frontal and transverse plane hip joint angles to minimise medial thigh motion is unlikely to lead to an improvement to performance. 相似文献
115.
Cheng Zeng Tatiana M. Permyakova Elena A. Smolianina Irina S. Morozova 《Journal of Intercultural Communication Research》2020,49(2):119-132
ABSTRACTEmployees who fail to balance work and life responsibilities are likely to experience job burnout and, ultimately, withdraw their engagement and voice in the workplace. The current study explored the relationships between employee burnout, work-family balance, and organizational dissent. More importantly, these relationships were tested in an under-researched and culturally unique context, Russia. Data collected from 232 full-time employees in the Perm region were analysed using multiple regression analysis. Analysis revealed that employee burnout is negatively related to articulated dissent and positively related to latent dissent. Furthermore, employees who receive managerial support for prioritizing family issues are less likely to experience job burnout. The influences of national culture and macroeconomic factors on the tested relationships are further discussed 相似文献
116.
In 2013, with the introduction of the Transparency Law in Spain, a number of Spanish newsrooms started working with data journalism methods. In Sweden, which has one of the oldest Freedom of Information acts in the world, newsrooms invested in the skill development of data journalism at approximately the same time. Because previous research suggests that access to public data has been one of the key driving forces for the development of data journalism worldwide, it is important to understand how legislation is actually shaping the practice of data journalism. Based on a survey of 66 key informants in Spain and Sweden and ten in-depth interviews with data journalists from five media companies in each country, we conducted a comparative study, building on the frameworks of media systems to explore data journalism practices in these two countries. The differences found indicate that the national and EU legislation in both nations shape journalistic strategies for accessing data, turning journalists at times into activists fighting for the right to access public data. Beyond the law, data journalists advocate for a transparency culture among the civil servants, in order to secure public accountability. 相似文献
117.
Quality in virtual education environments 总被引:1,自引:0,他引:1
Elena Barbera 《British journal of educational technology : journal of the Council for Educational Technology》2004,35(1):13-20
The emergence of the Internet has changed the way we teach and learn. This paper provides a general overview of the state of the quality of virtual education environments. First of all, some problems with the quality criteria applied in this field and the need to develop quality seals are presented. Likewise, the dimensions and subdimensions of an empirical instrument to improve and assess the quality of online education are examined. This tool has already been applied to several educational contexts; though not definitive, it aims to improve not only specific areas, but also the whole educational approach as a system. 相似文献
118.
Public libraries today are undergoing significant transformations as well as interacting with patrons in new and different ways (Knight Foundation 2017). Part of this transformation is the way libraries are engaging entire families. Libraries are playing a stronger role than ever before in supporting families to promote children’s early literacy and reading skills (Celano and Neuman 2015; Nagle et al. 2016; Neuman and Celano 2010), stimulating adult learning (Boden and Tashijan 2015), creating initiatives to improve family health (Morgan et al. 2016), providing services to families with extreme challenges such as those experiencing poverty, homelessness, food insecurity, and incarceration (Holt and Holt 2010; Terille 2016), as well as becoming spaces for families, especially those who are recent immigrants, to build new relationships and social networks (Khoir et al. 2017; Vårheim 2014). Despite these efforts, few studies have specifically sought to understand the organizational dimensions that support family engagement within a library system and the potential that these efforts have in promoting children’s learning not only in the early years, but also into and throughout middle childhood and adolescence. Based on a yearlong study investigating the power of family engagement in public libraries, this article considers how libraries can begin to adopt a systemic approach to family engagement to further innovate the library space. 相似文献
119.
The purpose of this study was to investigate the responses of salivary hormones and salivary secretory immunoglobulin A (SIgA) and anxiety in winners and losers during an international judo competition. Twenty-three trained, male, national-level judo athletes provided three saliva samples during a competition day: morning, in anticipation of competition after an overnight fast, mid-competition, and post-competition within 15 min post-fight for determination of salivary cortisol, salivary testosterone, salivary testosterone/cortisol ratio, SIgA absolute concentrations, SIgA secretion rate and saliva flow rate. The competitive state anxiety inventory questionnaire was completed by the athletes (n = 12) after the first saliva collection for determination of somatic anxiety, cognitive anxiety and self-confidence. Winners were considered 1-3 ranking place (n = 12) and losers (n = 11) below third place in each weight category. Winners presented higher anticipatory salivary cortisol concentrations (p = 0.03) and a lower mid-competition salivary testosterone/cortisol ratio (p = 0.003) compared with losers with no differences for salivary testosterone. Winners tended to have higher SIgA secretion rates (p = 0.07) and higher saliva flow rates (p = 0.009) at mid-competition. Higher levels of cognitive anxiety (p = 0.02) were observed in the winners, without differences according to the outcome in somatic anxiety and self-confidence. The results suggest that winners experienced higher levels of physiological arousal and better psychological preparedness in the morning, and as the competition progressed, the winners were able to control their stress response better. 相似文献
120.
AbstractSalvador López Gómez was a great exponent of gymnastics in Spain in the nineteenth and the twentieth century. His role as a teacher, a writer and even as a law developer who promoted gymnastics deserves a detailed study. For that reason, through primary sources of this era and, specially, papers from López Gómez himself, this paper depicts his long professional career, his conception of gymnastics and the constant efforts, not always properly rewarded, that he made for its social respect and acknowledgement during that time. 相似文献