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Hamdan MH Barbera S Kowal RC Page RL Ramaswamy K Joglar JA Karimkhani V Smith ML 《The American journal of cardiology》2002,89(9):1047-1051
This study assesses the effect of biventricular pacing on sympathetic nerve activity (SNA) in patients with depressed ejection fraction and intraventricular conduction delay (IVCD). Biventricular pacing has been shown to result in hemodynamic improvement in patients with depressed ejection fraction and IVCD. The effect of biventricular pacing on SNA, however, remains unclear. A total of 15 men with a mean ejection fraction of 25 +/- 4% were enrolled. Arterial pressure, central venous pressure and SNA were recorded during 3 minutes of right atrial (RA) pacing and RA-biventricular pacing. Pacing was performed at a rate 5 to 10 beats faster than sinus rhythm, with an atrioventricular interval equal to 100 ms during RA-biventricular pacing. RA-biventricular pacing resulted in greater arterial pressures (p <0.05) than RA pacing (146 +/- 15/83 +/- 11 vs 141 +/- 15/80 +/- 10 mm Hg). There were no differences in central venous pressures between the 2 pacing modes (p = 0.76). SNA was significantly less during RA-biventricular pacing (727 +/- 242 U) than during RA pacing (833 +/- 332 U) (p <0.02). Furthermore, there was a positive correlation between baseline QRS duration and the decrease in SNA noted with RA-biventricular pacing (r = 0.58, p = 0.03). Biventricular pacing results in improved hemodynamics and a decrease in SNA compared with intrinsic conduction in patients with left ventricular dysfunction and IVCD. If the current findings are also present with chronic biventricular pacing, then this form of therapy may have a positive impact on mortality. 相似文献
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Annamalai?AsaikkuttiEmail author Periyakali?Saravana?Bhavan Karuppaiya?Vimala Madhayan?Karthik 《Proceedings of the National Academy of Sciences, India. Section B.》2018,88(2):477-486
A 12- week feeding trial was conducted to determine the effects of dietary vitamin C levels on the growth performance, antioxidant ability, muscle composition and enzyme activity in freshwater prawn, Macrobrachium rosenbergii. The experimental basal diets were supplemented with M. rosenbergii at the rates of 0 (control), 25, 50, 75, 150 and 300 mg/kg dry feed weight and the assays were in triplicate. Growth performance, body composition, antioxidant activity and serum biochemistry parameters were determined. However, the present investigation revealed that prawns fed with diet supplemented with 25–150 mg/kg of vitamins C shows enhanced (P < 0.05) growth performance, including final weight and weight gain. Additionally, prawns fed with 25–150 mg/kg of vitamins C supplemented diets achieved significant (P < 0.05) improvement in growth performance, digestive enzyme activities, and muscle biochemical composition, while, the prawns fed with 150 mg/kg of vitamin C showed enhanced performance respectively. However, the prawns fed with above 150–300 mg/kg showed poor performance. The antioxidant enzymatic activity (SOD, CAT) metabolic enzyme status in muscle showed no significant (P > 0.05) alterations in prawns fed with 25–150 mg/kg of vitamin C supplemented diets. Therefore, the present findings suggested that 150 mg/kg of vitamin C could be supplemented for flexible enhanced survival, growth, antioxidant defense system and production of M. rosenbergii. 相似文献
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Swatantra Pratap Singh Karthik Rathinam Roni Kasher Christopher J. Arnusch 《RSC advances》2018,8(48):27027
Sericin, a protein waste product of the silk industry, was crosslinked with chitosan, and a chitosan–sericin conjugate (CS) was prepared, characterized and used to remove hexavalent chromium (Cr(vi)) ions and methyl orange (MO) dye from aqueous solutions. The CS was shown to effectively remove Cr(vi) ions and MO dye at maximum adsorption capacities (Langmuir) of 139 mg g−1 for Cr(vi) ions and 385 mg g−1 for MO dye. Moreover, the adsorption of both Cr(vi) ions and MO dye was highly pH dependent and varied under different experimental conditions. Cr(vi) ion and MO dye uptake by the CS was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometry analysis. Additionally, XPS analysis of the Cr(vi)-loaded CS revealed that Cr(vi) was reduced to the less toxic Cr(iii). The CS was shown not only to be highly amenable to regeneration, but also to be able to effectively remove MO dye and Cr(vi) ions from a binary mixture.Sericin, a protein waste product of the silk industry, was crosslinked with chitosan, and a chitosan–sericin conjugate (CS) was prepared, characterized and used to remove hexavalent chromium (Cr(vi)) ions and methyl orange dye from aqueous solutions. 相似文献
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Cynthia Scott Karthik Ramakrishnan Narayanan Vivek Chandran Saravanan Gurram Prashanthi 《Journal of oral and maxillofacial surgery》2021,79(6):1330.e1-1330.e12
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Karthik Ramakrishnan Cynthia Scott Pavithra Sarda. K Narayanan Vivek Chandran Saravanan 《Journal of cranio-maxillo-facial surgery》2021,49(6):488-493
This retrospective study aims to evaluate the correlation between the shape of the mandibular condylar head and the incidence of unilateral condylar fracture using computed tomography.Medical records of patients diagnosed with unilateral condylar fractures from the year 2012–2019 were reviewed. The shape of the condylar head on the non - fractured side was analysed using a Radiant Dicom Viewer. The analysis was done using both visual and analytical methods. In the analytical method, a horizontal line was drawn at the base of the curvature of the condylar head. The highest peak point of the head was marked, and a perpendicular line was drawn connecting the highest point to the horizontal line. The shape was categorized into four types as convex, flat, angled, and round based on these lines.201 CT scans were examined, of which 69 were excluded as they did not meet the inclusion criteria. The remaining 132 were included in our study. On examining the shape, flat-shaped condyle was seen in 57 scans (43.2%), followed by convex in 31 scans (23.4%), angled in 30 (22.7%) and round in 14 scans (10.6%). The relationship between the shape of the mandibular condylar head and the incidence of unilateral condylar fracture was analysed using a chi-square test, which showed high statistical significance (p value 0.0001). The flat-shaped condylar head was more prone to fracture, and the round-shaped condylar head was least prone to fracture.In conclusion, the shape of the mandibular condylar head had a statistically significant association with the incidence of unilateral condylar fracture. The assessment of the shape of the condylar head can be taken as a guide to suspect condylar fractures and other associated mandibular fractures. 相似文献
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Sean Molloy Maggie Lai Guy Pratt Karthik Ramasamy David Wilson Nasir Quraishi Martin Auger David Cumming Maqsood Punekar Michael Quinn Debo Ademonkun Fenella Willis Jane Tighe Gordon Cook Alistair Stirling Timothy Bishop Cathy Williams Bronek Boszczyk Jeremy Reynolds Mel Grainger Niall Craig Alastair Hamilton Isobel Chalmers Sam Ahmedzai Susanne Selvadurai Eric Low Charalampia Kyriakou the UK Spinal Myeloma Working Group 《British journal of haematology》2015,171(3):332-343
Myeloma is one of the most common malignancies that results in osteolytic lesions of the spine. Complications, including pathological fractures of the vertebrae and spinal cord compression, may cause severe pain, deformity and neurological sequelae. They may also have significant consequences for quality of life and prognosis for patients. For patients with known or newly diagnosed myeloma presenting with persistent back or radicular pain/weakness, early diagnosis of spinal myeloma disease is therefore essential to treat and prevent further deterioration. Magnetic resonance imaging is the initial imaging modality of choice for the evaluation of spinal disease. Treatment of the underlying malignancy with systemic chemotherapy together with supportive bisphosphonate treatment reduces further vertebral damage. Additional interventions such as cement augmentation, radiotherapy, or surgery are often necessary to prevent, treat and control spinal complications. However, optimal management is dependent on the individual nature of the spinal involvement and requires careful assessment and appropriate intervention throughout. This article reviews the treatment and management options for spinal myeloma disease and highlights the value of defined pathways to enable the proper management of patients affected by it. 相似文献