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991.
M. P. Narayanan Vaidyanathan Kannan K. P. Vinayan D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2011,26(4):347-353
Organic acid disorders are inherited metabolic disorders in which organic acids accumulate in tissues and biological fluids
of affected individuals. Classical organic acidurias include methylmalonic aciduria, propionic aciduria, isovaleric aciduria
and maple syrup urine disease (MSUD). They are considered the most frequent metabolic disorders among severely ill children.
Patients frequently present with acute symptoms early in life. 420 cases clinically suspected to have organic aciduria, with
upper age limit of 12 years for a 2-year period (January 2007–December 2008) were enrolled into this study. Metabolic acidosis
and neurological symptoms were the most common signs. Screening tests and thin layer chromatography were done for detection
of organic acidurias. Identification and quantitation of organic acids in urine and quantification of amino acids in blood
were done by high performance liquid chromatography. Out of 420 patients, 45 patients (10.7%) were found to have organic acidurias.
15 cases of methylmalonic aciduria, 16 cases of propionic aciduria, 13 cases of MSUD, and one case of isovaleric aciduria
were diagnosed. Results demonstrate the importance of testing for organic acidurias. Since organic aciduria may cause irreversible
brain damage if not treated, we recommend selective screening amongst severely ill children despite implied extra costs. 相似文献
992.
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
993.
We present evidence on productivity improvement experienced by the research institutes of the Chinese Academy of Sciences (CAS) after its implementation of the Knowledge Innovation Program (KIP). Using a balanced panel of data on R&D inputs and outputs of 59 research institutes in CAS, we analyze the productivity, technological and efficiency changes from 1997 to 2005. We document that the CAS research institutes have a productivity growth of 12.5% from 1998 to 2005, which can be further decomposed into 8.8% attributed to technological progress and 3.3% to efficiency improvement. Results of regional analysis show that institutes in Beijing and Shanghai, performed better than institutes in other regions during the same period. 相似文献
994.
995.
Epshteyn AA Maher S Taylor AJ Holton AB Borenstein JT Cuiffi JD 《Biomicrofluidics》2011,5(4):46501-465016
The design and fabrication of a membrane-integrated microfluidic cell culture device (five layers,≤500 μm total thickness) developed for high resolution microscopy is reported here. The multi-layer device was constructed to enable membrane separated cell culture for tissue mimetic in vitro model applications and pharmacodynamic evaluation studies. The microdevice was developed via a unique combination of low profile fluidic interconnect design, substrate transfer methodology, and wet silane bonding. To demonstrate the unique high resolution imaging capability of this device, we used oil immersion microscopy to image stained nuclei and mitochondria in primary hepatocytes adhered to the incorporated membrane 相似文献
996.
In this work a disposable, parallel microbioreactor (MBR) suitable for screening in batch or continuous mode is presented. The reactor consists of five parallel microchambers made of poly(dimethylsiloxane) bonded to a glass substrate. A grid structure is engraved on each chamber, allowing subsequent morphology imaging. Measurements are recorded over the entire cultivation period with constant parameters, namely, position and focus in the z-axis. The microdevice may be used for either parallel, uni- or multiparametric screening, and overcomes the drawback of gridless microwell plates which require expensive equipment such as an inverted microscope with an automatic stage. To validate the scalability from laboratory scale to microscale, and thus the cultivation protocol in the MBR, the germination of fungal spores (A. ochraceus) is evaluated for two different key magnitudes (pH and temperature) and compared to the results obtained from conventional laboratory scale systems (flasks and agar plates). Information on germination capacity with regard to interspecies' variability allows for optimization of industrial processes as optimal pH and temperature matched to the mesoscopic cultivation systems. The germination conditions therefore remain unaffected inside the MBR, while providing the following advantages: (i) dramatic reduction of medium consumption, (ii) submerged cultivation with constant oxygen supply, (iii) assured low cost and disposability, and (iv) possibility of a continuous cultivation mode. 相似文献
997.
Miller PR Gittard SD Edwards TL Lopez DM Xiao X Wheeler DR Monteiro-Riviere NA Brozik SM Polsky R Narayan RJ 《Biomicrofluidics》2011,5(1):13415
In this study, carbon fiber electrodes were incorporated within a hollow microneedle array, which was fabricated using a digital micromirror device-based stereolithography instrument. Cell proliferation on the acrylate-based polymer used in microneedle fabrication was examined with human dermal fibroblasts and neonatal human epidermal keratinocytes. Studies involving full-thickness cadaveric porcine skin and trypan blue dye demonstrated that the hollow microneedles remained intact after puncturing the outermost layer of cadaveric porcine skin. The carbon fibers underwent chemical modification in order to enable detection of hydrogen peroxide and ascorbic acid; electrochemical measurements were demonstrated using integrated electrode-hollow microneedle devices. 相似文献
998.
This study evaluated the interpersonal sensitivity of third culture individuals, defined as people who lived in a country other than that of their nationality during their developmental years, by comparing them to mono-cultured individuals. While the notion that third culture individuals develop enhanced perceptual skills as a result of intercultural adaptation is widely accepted in popular and professional literature, this assertion has not been empirically tested. Previous research on intercultural communication competence and adaptation has almost exclusively focused on intercultural exposure among adults. This study collected data from 142 individuals using web-based surveys. The instruments measured two aspects of participants’ interpersonal sensitivity: social and emotional sensitivity. Results showed that third culture individuals have significantly higher social sensitivity than mono-cultured individuals, while mono-cultured individuals reported higher emotional sensitivity. Additionally, no significant correlation was found between greater intercultural experience and increased interpersonal sensitivity. 相似文献
999.
1000.
Although triathlon is growing in popularity at a remarkable rate, it has not been extensively studied. The aims of this research were to identify preparation strategies used by triathletes and to categorize these strategies according to gender and consultation with triathlon coaches. Survey data collected from 401 triathletes (207 males, 194 females) revealed training, nutritional, and mental preparation habits. Most participants engaged in strength training, consumed food and/or fluids during and after training, set training and competition goals, and applied mental preparation strategies during training and the hour before racing. Water was the most commonly consumed fluid; positive self-talk was the most used mental strategy. Participants were more likely to consult with a triathlon coach than a nutrition or sport psychology professional. Athletes with more years of experience in triathlon and those competing in longer distances were more likely to consult a triathlon coach. Female triathletes were more likely than male triathletes to train with others, use mental preparation strategies, and report feeling anxious before competitions. More male triathletes reported using nutritional supplements during training than their female counterparts. These findings add to the limited research base on triathletes' training habits, and hopefully will help guide practitioners who work with this group. The results provide guidance for collaborative efforts among training, nutrition, and mental health professionals to best support triathletes. 相似文献