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Aim To analyse volumetrically using spiral computed tomography (SCT) the efficacy of various techniques to fill root canals.
Methodology Root canals in 40 maxillary central incisors were instrumented with K-files to size 60 and the volume of the canal measured using SCT. The teeth were divided into four groups of 10 each and root filled by lateral compaction, Thermafil, Obtura II and System B techniques, respectively. AH plus was used as sealer with all techniques. The filled volume in each canal was measured using SCT and the percentage of obturated volume (POV) was calculated. The data were statistically analysed using Kruskal–Wallis test and Mann–Whitney U -test.
Results The four groups were comparable in canal volume. The overall POV was 80.4%, 93.3%, 84.8% and 93.7% for lateral compaction, Thermafil, Obtura II and System B, respectively ( P < 0.05).
Conclusion The greatest POV was obtained with System B and Thermafil. Voids were seen in all root fillings. 相似文献
Methodology Root canals in 40 maxillary central incisors were instrumented with K-files to size 60 and the volume of the canal measured using SCT. The teeth were divided into four groups of 10 each and root filled by lateral compaction, Thermafil, Obtura II and System B techniques, respectively. AH plus was used as sealer with all techniques. The filled volume in each canal was measured using SCT and the percentage of obturated volume (POV) was calculated. The data were statistically analysed using Kruskal–Wallis test and Mann–Whitney U -test.
Results The four groups were comparable in canal volume. The overall POV was 80.4%, 93.3%, 84.8% and 93.7% for lateral compaction, Thermafil, Obtura II and System B, respectively ( P < 0.05).
Conclusion The greatest POV was obtained with System B and Thermafil. Voids were seen in all root fillings. 相似文献
675.
Diverse proteins are known to be capable of forming amyloid aggregates, self-seeding fibrillar assemblies that may be biologically functional or pathological. Well-known examples include neurodegenerative disease-associated proteins that misfold as amyloid, fungal prion proteins that can transition to a self-propagating amyloid form and certain bacterial proteins that fold as amyloid at the cell surface and promote biofilm formation. To further explore the diversity of amyloidogenic proteins, generally applicable methods for identifying them are critical. Here we describe a cell-based method for generating amyloid aggregates that relies on the natural ability of Escherichia coli cells to elaborate amyloid fibrils at the cell surface. We use several different yeast prion proteins and the human huntingtin protein to show that protein secretion via this specialized export pathway promotes acquisition of the amyloid fold specifically for proteins that have an inherent amyloid-forming propensity. Furthermore, our findings establish the potential of this E. coli-based system to facilitate the implementation of high-throughput screens for identifying amyloidogenic proteins and modulators of amyloid aggregation. 相似文献
676.
Vidya A. Arankalle Ruta Kulkarni Nandini Malshe Sonali Palkar Sanjay Lalwani Akhilesh Chandra Mishra 《Journal of medical virology》2019,91(8):1566-1570
Respiratory syncytial virus (RSV) causes significant infant mortality worldwide and a vaccine may be available soon. This study determined age-stratified anti-RSV antibody positivity (enzyme-linked immunosorbent assay [ELISA]) at Pune, India (cord blood-85 years). Antibody positivity declined from 100% at birth to 71.3% (3 months), and 0.7% (6 months). A significant rise was noted at 15 months (16%), 16 to 24 months (64.5%) and 4 years (95.2%) with concomitant IgM-anti-RSV positivity indicative of recent infection. Antibody decline was higher in infants born preterm than full-term. Across subsequent age groups including the elderly, antibody positivity was similar and comparable, suggestive of repeated exposure to the virus. Early protection/vaccination is essential for the infant population. 相似文献
677.
Nandini Vallath 《Indian Journal of Palliative Care》2010,16(1):1-7
Chronic pain is multi-dimensional. At the physical level itself, beyond the nociceptive pathway, there is hyper arousal state of the components of the nervous system, which negatively influences tension component of the muscles, patterns of breathing, energy levels and mindset, all of which exacerbate the distress and affect the quality of life of the individual and family. Beginning with the physical body, Yoga eventually influences all aspects of the person: vital, mental, emotional, intellectual and spiritual. It offers various levels and approaches to relax, energize, remodel and strengthen body and psyche. The asanas and pranayama harmonize the physiological system and initiate a “relaxation response” in the neuro endocrinal system. This consists of decreased metabolism, quieter breathing, stable blood pressure, reduced muscle tension, lower heart rate and slow brain wave pattern. As the neural discharge pattern gets modulated, hyper arousal of the nervous system and the static load on postural muscle come down. The function of viscera improves with the sense of relaxation and sleep gets deeper and sustained; fatigue diminishes. Several subtle level notional corrections can happen in case the subject meditates and that changes the context of the disease, pain and the meaning of life. Meditation and pranayama, along with relaxing asanas, can help individuals deal with the emotional aspects of chronic pain, reduce anxiety and depression effectively and improve the quality of life perceived. 相似文献
678.
Megha Sharda T. Padma Subhadra Sanchita Sahay Chetan Nagaraja Latika Singh Ramesh Mishra Amit Sen Nidhi Singhal Donna Erickson Nandini C. Singh 《Neuroscience letters》2010
The objective of this study was to find a pattern in vocalizations of children with Autism Spectrum Disorder (ASD). We compared the intonational features of 15 children with ASD who showed speech, aged 4–10 years, with 10 age-matched typically developing controls. Exaggerated pitch, pitch range, pitch excursion and pitch contours were observed in speech of children with autism, but absent in age-matched controls. These exaggerated features, which are distinctive characteristics of motherese, were also seen in interactions of an independent group of 8 mothers of typical infants using child-directed speech. Our findings provide the first evidence of a distinct pattern in vocal output from children with autism. They also demonstrate that speech patterns might follow a delayed developmental trajectory in these children. 相似文献
679.
Ronald C. Plotnikoff Steven T. Johnson Nandini Karunamuni Normand G. Boule 《Journal of health communication》2013,18(8):846-858
Physical activity (PA) is a key management strategy for type 2 diabetes. Despite the known benefits, PA levels are low. Whether the low level of PA is related to lack of knowledge or support is not fully understood. This study was conducted to describe where and how often adults with type 2 diabetes receive and seek information related to PA and examine the relationships between the source and quality of PA information with PA behaviors. A series of questions related to the source and quality of PA information were added to a baseline survey distributed to the participants (N = 244) of the Canadian Aerobic and Resistance Training in Diabetes (CARED) study. Physicians and television were found to be the main sources of PA-related information. In our cross-sectional model, sources of PA-related information other than that from health care professionals explained 14% (p = .05) and 16% (p < .05) of the variance for aerobic-based and resistance training behaviors and 22% (p < .01) and 15% (p < .05) for these behaviors in our longitudinal model. Physical activity (PA)-related information is widely available to adults with type 2 diabetes. Neither the quantity nor the quality of the PA information provided by health care professionals predicted PA behavior. These data provide further insight into the modes with which PA can be promoted to adults with type 2 diabetes. 相似文献
680.
Arun K. Sinha Upendra K. Sharma Nandini Sharma 《International journal of food sciences and nutrition》2013,64(4):299-326
Vanilla, being the world's most popular flavoring materials, finds extensive applications in food, beverages, perfumery and pharmaceutical industry. With the high demand and limited supply of vanilla pods and the continuing increase in their cost, numerous efforts of blending and adulteration in natural vanilla extracts have been reported. Thus, to ensure the quality of vanilla extracts and vanilla-containing products, it is important to develop techniques to verify their authenticity. Quantitatively, vanillin is the major compound present in the vanilla pods and the determination of vanillin is a vital consideration in natural vanilla extracts. This paper provides a comprehensive account of different extraction processes and chromatographic techniques applied for the separation, identification and determination of chemical constituents of vanilla. The review also provides an account of different methods applied for the quantification and the authentification of chemical constituents of vanilla extract. As the various properties of vanilla are attributed to its main constituent vanillin, its physico-chemical and bioactive properties have also been outlined. 相似文献