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981.
Biswas D Vettriselvi V Choudhury J Jothimalar R 《Indian journal of clinical biochemistry : IJCB》2011,26(2):172-177
Mutations in different regions of adiponectin gene have been reported to be associated with obesity, atherosclerosis and type
2 diabetes mellitus. The present study was aimed to investigate the association among SNP 45 T > G of adiponectin gene and
type 2 diabetes in South Indian population. 75 clinically diagnosed case of type 2 diabetes were studied and compared with
75 apparently healthy controls. The genotype frequency of SNP45 T > G in exon 2 of adiponectin gene was determined by PCR
based restriction enzyme analysis using the restriction enzyme SmaI. (recognition site: CCC↓GGG). Three kind of genotypes: wild type TT (470 bp), heterozygous type TG (470 bp, 336 bp, 134 bp)
and homozygote mutant type GG (336 bp, 134 bp) were studied. A positive association has been found between SNP45 T > G and
type 2 diabetes in the study population (P = 0.010, OR = 3.797, 95% CI = 1.312–10.983). Therefore, SNP45T > G in adiponectin gene may be one of the risk factors for
type 2 diabetes. 相似文献
982.
India seems to have the highest prevalence of osteoporosis. With growing awareness of osteoporosis and its impact on life
span especially in India, special attention is being paid to early detection, management and treatment of postmenopausal osteoporosis
in women. Measurement of BMD and osteocalcin are of value in estimating bone turnover rates. The aim of this study is (1)
to measure the specific, sensitive bone formation marker such as osteocalcin and BMD in postmenopausal osteoporosis women
and postmenopausal non-osteoporosis women; (2) the follow up study to evaluate the impact of specific antiresorptive therapy
(alendronate + calcium + vitamin D) regimen in postmenopausal osteoporosis by assaying osteocalcin and BMD. Sixty clinically
diagnosed postmenopausal osteoporosis patients and 60 normal subjects (postmenopausal non-osteoporosis women) were recruited
as control. Mean bone mineral density T score and Z score was significantly decreased (P < 0.001) in postmenopausal osteoporosis patients as compared to controls. Highly significant increase in the mean score of
BMD—T score and Z score from baseline to post therapy of 3 months was observed in postmenopausal osteoporosis women. Serum osteocalcin levels
were significantly increased (P < 0.001) as compared to control group. Serum osteocalcin levels were decreased significantly (P < 0.001) from baseline to post therapy of 3 months in postmenopausal osteoporosis women. BMD is the best quantifiable predictor
of osteoporotic fracture and osteocalcin is specific, sensitive, promising, currently used marker for better prognosis of
osteoporosis and for monitoring responses to antiresorptive therapy. 相似文献
983.
Franky D. Shah Rasheedunnisa Begum Bhairavi N. Vajaria Kinjal R. Patel Jayendra B. Patel Shilin N. Shukla Prabhudas S. Patel 《Indian journal of clinical biochemistry : IJCB》2011,26(4):326-334
Oral cancer has emerged as an alarming public health problem with increasing incidence and mortality rates all over the world.
Therefore, the implementation of newer screening and early detection approaches are of utmost importance which could reduce
the morbidity and mortality associated with this disease. Sensitive and specific biomarkers for oral cancer are likely to
be most effective for screening, diagnosis, staging and follow-up for this dreaded malignancy. Unlike other deep cancers,
oral cancer is located in oral cavity. Hence, the direct contact between saliva and oral cancer lesion makes the measurement
of tumor markers in saliva an attractive alternative to serum and tissue testing. The DNA, RNA and protein molecules derived
from the living cancer cells can be conveniently obtained from saliva. Thus, salivary biomarkers, a non-invasive alternative
to serum and tissue-based biomarkers may be an effective modality for early diagnosis, prognostication and monitoring post
therapy status. In the current post-genomic era, various technologies provide opportunities for high-throughput approaches
to genomics and proteomics; which have been used to evaluate altered expressions of gene and protein targets in saliva of
oral cancer patients. The emerging field of salivary biomarkers has great potentials to prove its clinical significance to
combat oral cancer. Hence, we have reviewed importance of several salivary genomics and proteomics biomarkers for oral cancer. 相似文献
984.
Newman WR 《Isis; an international review devoted to the history of science and its cultural influences》2011,102(2):313-321
Over the last two decades a new scholarship on alchemy has emerged, leading to a fundamental reformulation of knowledge about alchemists and their activities. We now know that medieval and early modern alchemists employed experiment in concert with theory to demonstrate the existence of stable "chymical atoms," which were thought to combine with one another according to a hierarchical theory of matter. Employing laboratory-based analysis and synthesis, alchemists were among the first explicitly to enunciate the principle of mass balance and to show that materials are compounded of the ingredients into which they can be physically decomposed. Perhaps even more surprisingly, these convictions and practices arose out of the interaction of alchemical practice with scholastic Aristotelianism, long viewed by historians of the Scientific Revolution as antithetical to experiment. Thus the new historiography challenges both a long-standing marginalization of alchemy itself and a commonplace view of Aristotelianism as inimical to the early modern growth of experimental science. 相似文献
985.
The present paper sheds some light on a mathematical model for blood flow through stenosed arteries with axially variable peripheral layer thickness and variable slip at the wall. The model consists of a core region of suspension of all the erythrocytes assumed to be a Casson fluid and a peripheral layer of plasma as a Newtonian fluid. For such models, in literature, the peripheral layer thickness and slip velocity are assumed a priori based on experimental observations. In the present analysis, new analytic expressions for the thickness of the peripheral layer, slip velocity and core viscosity have been obtained in terms of measurable quantities (flow rate (Q), centerline velocity (U), pressure gradient (−dp/dz), plasma viscosity (μp) and yield stress (θ)). Using the experimental values of Q, U, (−dp/dz), μp and θ, the values of the peripheral layer thickness, core viscosity, and slip velocity at the wall have been computed. The theoretically obtained peripheral layer thickness has been compared with its experimental value. It is found that the agreement between the two is very good (error<1.4%). Further, a comparison between theoretical and experimental values of core viscosity is made and it is observed that the error between the two becomes 3.7465% in the case of two-layered model (Casson-Newtonian) for tube diameter 40 μm. The analysis developed here could be used to determine the more accurate values of the apparent viscosity of blood, agreeability, rigidity and deformability of red cells. This information of blood could be useful in the development of new diagnosis tools for many diseases. 相似文献
986.
A simple design method for the cosine-modulated filter banks using weighted constrained least square technique 总被引:1,自引:0,他引:1
This paper presents a simple and efficient design method for cosine-modulated filter banks with prescribed stopband attenuation, passband ripple, and channel overlap. The method casts the design problem as a linear minimization of filter coefficients such that their value at ω=π/2M is 0.707, which results in a simpler, more direct design procedure. The weighted constrained least squares technique is exploited for designing the prototype filter for cosine modulation (CM) filter banks. Several design examples are included to show the increased efficiency and flexibility of the proposed method over the exiting methods. An application of the proposed method is considered in the area of sub-band coding of the ECG and speech signals. 相似文献
987.
In this article we propose that medical practice evolves as a result of progress along three different pathways: improvement in the ability to develop effective medical technologies, learning in medical practice, and advances in biomedical scientific understanding of disease. The relative importance of these three pathways varies from case to case, and often they interact strongly. More specifically, we argue here that in cases of therapeutic innovation where a new medical technology is involved the advance in medical practice is driven largely by the ability to develop and use effective medical artifacts and the interactive sequence among these interdependent pathways often starts with what is learned in practice and not in science. While we state this argument in general, we develop it in detail in a longitudinal and contextual case study of the emergence and evolution of a treatment for advanced heart failure based on an implantable device, the Left Ventricular Assist Device (LVAD). Our findings show that an essential aspect of the evolution of the LVAD therapy is collective and cumulative learning that requires experience that only can be gained through the actual use of LVADs. We discuss the theoretical and policy implications that follow from our understanding of how medical practice evolves for research on the evolution of medical practices and new medical technologies, and policies about the evaluation of rapidly moving medical practices and clinical research involved in their advancement. 相似文献
988.
Gurpreet K Rana Doreen R Bradley Stanley J Hamstra Paula T Ross Robert E Schumacher John G Frohna Hilary M Haftel Monica L Lypson 《Journal of the Medical Library Association》2011,99(1):77-81
Objective:
The objective of this study was to validate an assessment instrument for MEDLINE search strategies at an academic medical center.Method:
Two approaches were used to investigate if the search assessment tool could capture performance differences in search strategy construction. First, data from an evaluation of MEDLINE searches from a pediatric resident''s longitudinal assessment were investigated. Second, a cross-section of search strategies from residents in one incoming class was compared with strategies of residents graduating a year later. MEDLINE search strategies formulated by faculty who had been identified as having search expertise were used as a gold standard comparison. Participants were presented with a clinical scenario and asked to identify the search question and conduct a MEDLINE search. Two librarians rated the blinded search strategies.Results:
Search strategy scores were significantly higher for residents who received training than the comparison group with no training. There was no significant difference in search strategy scores between senior residents who received training and faculty experts.Conclusion:
The results provide evidence for the validity of the instrument to evaluate MEDLINE search strategies. This assessment tool can measure improvements in information-seeking skills and provide data to fulfill Accreditation Council for Graduate Medical Education competencies.Highlights
- The University of Michigan MEDLINE Search Assessment tool can be used to assess search skills in residency education.
- Five elements were identified as critical elements in the development of an effective MEDLINE search strategy: inclusion of all search concepts, appropriate use of Medical Subject Headings, appropriate use of search limits, successful combination of all concepts, and search efficiency.
Implications
- This validated assessment tool can serve as an effective means to measure improvements in residents'' information-seeking skills and provide data to fulfill Accreditation Council for Graduate Medical Education competencies.
989.
Edwards TL Harper JC Polsky R Lopez DM Wheeler DR Allen AC Brozik SM 《Biomicrofluidics》2011,5(4):44115-4411514
Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices. 相似文献
990.
In this special issue of Biomicrofluidics, a wide variety of applications of microfluidics to tissue engineering and cell biology are presented. The articles illustrate the benefits of using microfluidics for controlling the cellular environment in a precise yet high rate manner using minimum reagents. The topic is very timely and takes a stab at portraying a glimpse of what is to come in this exciting and emerging field of research. 相似文献