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151.
K. Pratibha T. Seenappa K. Ranganath 《Indian journal of clinical biochemistry : IJCB》2007,22(2):158-161
Alkaptonuria, a metabolic disorder characterized by a triad of homogentisic aciduria, arthritis and ochronosis is one of the
first conditions in the charter of group of inborn errors of metabolism proposed to have Mendelian recessive inheritance.
It is due to the deficiency of the enzyme homogentisic acid oxidase which catalyzes the conversion of homogentisic acid to
maleylacetoacetic acid in the catabolism of tyrosine. Homogentisic acid thus accumulates in cells and body fluids and its
oxidized polymers bind to collagen, leading to progressive deposition of grey to bluish black pigment resulting in degenerative
changes in cartilage, intervertebral disc and other connective tissues, leading to arthritis which is the only disabling effect
in an affected older individual. However the diagnosis can be made in neonates when blackish stain is noticed in an unwashed
diaper. Alkaptonuria is treated symptomatically, surgical intervention necessitates in advanced stages, treatment with ascorbic
acid (Vitamin C) and dietary restrictions of food containing phenylalanine and tyrosine have proved to be successful in alleviating
the symptoms. 相似文献
152.
H.T. Chieh 《Journal of The Franklin Institute》1973,295(1):69-79
An effective way of constructing transforming matrix which similarly transforms a real square matrix to a quasi-diagonal form, is obtained. The transforming matrix as well as the quasi-diagonal form are real, regardless whether the given matrix has real eigenvalues or not. Formulas are included; they can be applied conveniently to evaluate a matrix function f(A) from the given scalar function f(λ). Three examples are given to illustrate the ease of application. These are the solutions of system differential equations of first and second order, and the determination of Nth root of a square matrix. 相似文献
153.
T. Malati G. Rajani Kumari P. V. L. N. Murthy Ch. Ram Reddy B. Surya Prakash 《Indian journal of clinical biochemistry : IJCB》2006,21(1):34-40
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the
present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma
Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating
patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and
10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase
(P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy
males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death. 相似文献
154.
Shilpa Sivashankar Sumeyra Agambayev Yousof Mashraei Er Qiang Li Sigurdur T. Thoroddsen Khaled Nabil Salama 《Biomicrofluidics》2016,10(3)
This paper proposes a new “twisted” 3D microfluidic mixer fabricated by a laser writing/microfabrication technique. Effective and efficient mixing using the twisted micromixers can be obtained by combining two general chaotic mixing mechanisms: splitting/recombining and chaotic advection. The lamination of mixer units provides the splitting and recombination mechanism when the quadrant of circles is arranged in a two-layered serial arrangement of mixing units. The overall 3D path of the microchannel introduces the advection. An experimental investigation using chemical solutions revealed that these novel 3D passive microfluidic mixers were stable and could be operated at a wide range of flow rates. This micromixer finds application in the manipulation of tiny volumes of liquids that are crucial in diagnostics. The mixing performance was evaluated by dye visualization, and using a pH test that determined the chemical reaction of the solutions. A comparison of the tornado-mixer with this twisted micromixer was made to evaluate the efficiency of mixing. The efficiency of mixing was calculated within the channel by acquiring intensities using ImageJ software. Results suggested that efficient mixing can be obtained when more than 3 units were consecutively placed. The geometry of the device, which has a length of 30 mm, enables the device to be integrated with micro total analysis systems and other lab-on-chip devices. 相似文献
155.
156.
Middle grades science teachers need professional support in practice as they implement new inquiry-based science. Professional
development schools can provide this bottom-up support through connecting preservice and inservice teacher education programs
in classroom practice. In this study, coteaching arrangements with secondary science education majors provided additional
teachers in the classroom to support a materials-rich curriculum and the needed associated pedagogies. Science education majors
provided needed assistance in troubleshooting difficulties with the new curriculum. They also provided needed content knowledge
to support inquiry, along with creating moments and space for teachers to reflect on inquiry practice. Ongoing assistance
by preservice teachers allowed inservice teachers to progress from logistical concerns in implementing kit curriculum to concerns
regarding student learning and the supporting professional development.
相似文献
Charles J. EickEmail: |
157.
Students rarely ask questions related to course content in large-format introductory classes. The use of a Web-based forum devoted to student-generated questions was explored in a second-semester introductory biology course. Approximately 80% of the enrolled students asked at least one question about course content during each of three semesters during which this approach was implemented. About 95% of the students who posted questions reported reading the instructor's response to their questions. Although doing so did not contribute to their grade in the course, approximately 75% of the students reported reading questions posted by other students in the class. Approximately 60% of the students reported that the Web-based question-asking activity contributed to their learning of biology. 相似文献
158.
Teachers' education, classroom quality, and young children's academic skills: results from seven studies of preschool programs 总被引:10,自引:0,他引:10
Early DM Maxwell KL Burchinal M Alva S Bender RH Bryant D Cai K Clifford RM Ebanks C Griffin JA Henry GT Howes C Iriondo-Perez J Jeon HJ Mashburn AJ Peisner-Feinberg E Pianta RC Vandergrift N Zill N 《Child development》2007,78(2):558-580
In an effort to provide high-quality preschool education, policymakers are increasingly requiring public preschool teachers to have at least a Bachelor's degree, preferably in early childhood education. Seven major studies of early care and education were used to predict classroom quality and children's academic outcomes from the educational attainment and major of teachers of 4-year-olds. The findings indicate largely null or contradictory associations, indicating that policies focused solely on increasing teachers' education will not suffice for improving classroom quality or maximizing children's academic gains. Instead, raising the effectiveness of early childhood education likely will require a broad range of professional development activities and supports targeted toward teachers' interactions with children. 相似文献
159.
Income is not enough: incorporating material hardship into models of income associations with parenting and child development 总被引:2,自引:0,他引:2
Although research has clearly established that low family income has negative impacts on children's cognitive skills and social-emotional competence, less often is a family's experience of material hardship considered. Using the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (N=21,255), this study examined dual components of family income and material hardship along with parent mediators of stress, positive parenting, and investment as predictors of 6-year-old children's cognitive skills and social-emotional competence. Support was found for a model that identified unique parent-mediated paths from income to cognitive skills and from income and material hardship to social-emotional competence. The findings have implications for future study of family income and child development and for identification of promising targets for policy intervention. 相似文献
160.
Richard Spoth Linda Trudeau Cleve Redmond Chungyeol Shin Mark E. Feinberg Mark T. Greenberg 《Child development》2019,90(6):1847-1855
This study examines crossover effects of adolescent substance misuse preventive interventions on academic success in college. It evaluates pathways of influence on college grades, via effects on school engagement, problem-solving skills, and substance misuse in high school. Data were collected as part of an Randomized Controlled Trial (RCT) evaluating a multicomponent intervention conducted in 28 school districts with middle school students. At age 19, study participants (N = 1,488) enrolled in college reported on college grades. The model fit the data, supporting hypothesized pathways of intervention impacts. Inclusion of a significant direct effect on college grades further improved model fit. Results support the potential for universal substance misuse preventive interventions delivered by community partnerships during middle school to yield effects on long-term academic success. 相似文献