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81.
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Rao Gurugubelli Krishna 《The journal of maternal-fetal & neonatal medicine》2018,31(19):2634-2640
Intrauterine growth restriction (IUGR) is a pregnancy specific disease characterized by decreased growth rate of fetus than the normal growth potential at particular gestational age. In the current scenario it is a leading cause of fetal and neonatal morbidity and mortality. In the last decade exhilarating experimental studies from several laboratories have provided fascinating proof for comprehension of molecular basis of IUGR. Atypical expression of enzymes governed by TGFβ causes the placental apoptosis and altered expression of TGFβ due to hyper alimentation causes impairment of lung function. Crosstalk of cAMP with protein kinases plays a prominent role in the regulation of cortisol levels. Increasing levels of NOD1 proteins leads to development of IUGR by increasing the levels of inflammatory mediators. Increase in leptin synthesis in placental trophoblast cells is associated with IUGR. In this review, we emphasize on the regulatory mechanisms of IUGR and its associated diseases. They may help improve the in-utero fetal growth and provide a better therapeutic intervention for prevention and treatment of IUGR. 相似文献
83.
Two Automated Techniques for Carotid Lumen Diameter Measurement: Regional versus Boundary Approaches
Tadashi Araki P. Krishna Kumar Harman S. Suri Nobutaka Ikeda Ajay Gupta Luca Saba Jeny Rajan Francesco Lavra Aditya M. Sharma Shoaib Shafique Andrew Nicolaides John R. Laird Jasjit S. Suri Fellow AIMBE 《Journal of medical systems》2016,40(7):182
The degree of stenosis in the carotid artery can be predicted using automated carotid lumen diameter (LD) measured from B-mode ultrasound images. Systolic velocity-based methods for measurement of LD are subjective. With the advancement of high resolution imaging, image-based methods have started to emerge. However, they require robust image analysis for accurate LD measurement. This paper presents two different algorithms for automated segmentation of the lumen borders in carotid ultrasound images. Both algorithms are modeled as a two stage process. Stage one consists of a global-based model using scale-space framework for the extraction of the region of interest. This stage is common to both algorithms. Stage two is modeled using a local-based strategy that extracts the lumen interfaces. At this stage, the algorithm-1 is modeled as a region-based strategy using a classification framework, whereas the algorithm-2 is modeled as a boundary-based approach that uses the level set framework. Two sets of databases (DB), Japan DB (JDB) (202 patients, 404 images) and Hong Kong DB (HKDB) (50 patients, 300 images) were used in this study. Two trained neuroradiologists performed manual LD tracings. The mean automated LD measured was 6.35 ± 0.95 mm for JDB and 6.20 ± 1.35 mm for HKDB. The precision-of-merit was: 97.4 % and 98.0 % w.r.t to two manual tracings for JDB and 99.7 % and 97.9 % w.r.t to two manual tracings for HKDB. Statistical tests such as ANOVA, Chi-Squared, T-test, and Mann-Whitney test were conducted to show the stability and reliability of the automated techniques. 相似文献
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Tobacco smoke, active or passive exposure was the major cause of preventable morbidity and mortality in the world during twentieth century and will continue to be the same in the twenty-first century also if the current trends continue. Both active and passive smoking are having significance in relation to child health. Exposure starts antenatally from placenta to the fetus and later phases through passive exposure to experimental and regular smoking and ultimately addiction and habitual smoking. Evidences are in favour of causal relationship with intrauterine growth restriction, sudden infant death syndrome, decreased pulmonary function, increased risk for respiratory tract infection, otitis media, wheeze, asthma, neurobehavioral disorders, cleft palate and triggering pathogenesis of fetal and childhood onset of adult diseases, especially pulmonary and cardio vascular diseases. All these facts stress the importance of behavioral changes in the population as well as stringent public health measures and legislation for ensuring smoke free work places, public places and households for children. M POWER- Package by WHO is a novel global initiative taking us closer to the target of achieving tobacco free environment for children in the near future. 相似文献
86.
Mohamed Rafiq Gollapalle Lakshminarayanashastry Viswanatha Dattatray Anturlikar Suryakanth Mohammed Azeemuddin Mahalingaiah Jagadeesh Krishna Dhanush Pralhad Sadashiv Patki 《Scientia pharmaceutica》2013,81(3):833-842
In the present study, the protective effect of Bresol® – a polyherbal formulation – was evaluated in an experimental model of cigarette smoke (CS)-induced COPD in rats. Ten minutes daily exposure to CS for 7 weeks caused significant elevation of TNF-α (p<0.01) and total protein (p<0.01) in the bronchoalveolar lavage fluid (BALF) of positive untreated control animals, indicating ongoing inflammatory process in the lungs. Further, histopathological findings have confirmed the presence of pathological lesions in the trachea and lungs. Five weeks of post-treatment with Bresol® (250 and 500 mg/kg, p.o.) showed significant and dose-dependent anti-inflammatory effects against CS-induced lung abnormalities by maintaining the TNF-α and total protein levels within the normal range. Additionally, Bresol®-treated animals showed normal cyto-architecture of the trachea and lungs. In conclusion, Bresol® showed dose-dependent protection against CS-induced lung and tracheal injury in rats, which further indicates, Bresol® is a useful healing agent, may help to decelerate the progression of COPD, and reduce the exacerbations in patients. 相似文献
87.
Krishna J. Rocha‐Singh MD FACC Victor Novack MD PhD Michael Pencina PhD Ralph D'Agostino PhD Gary Ansel MD FACC Kenneth Rosenfield MD FACC Michael R. Jaff DO FACC 《Catheterization and cardiovascular interventions》2011,78(5):779-789
Objective : To provide safety and performance goals for prospective single‐arm trials of bare metal renal artery stenting in patients with resistant hypertension associated with high grade atherosclerotic renal artery stenosis. Background : To date, there have been no US Pre‐Market Approval (PMA) bare metal renal stent device trials which have focused on improvement of blood pressure control as a primary effectiveness endpoint. Methods : Analysis of subject‐level data from three large industry sponsored pre‐market approval (PMA) trials was performed. Hypertensive patients (≥155 mmHg) with a ≥50% atherosclerotic renal artery stenosis were included. Thirty day and 9‐month systolic and diastolic blood pressure measurements, renal function and 9‐month duplex ultrasound assessment of renal artery patency were analyzed. Results : Initial data analysis of 600 patients from the 3 PMA trials identified 286 patients who met inclusion criteria. The mean baseline systolic blood pressure was 177.8 ± 19.3 mmHg with a mean 68.1% diameter renal artery stenosis. Nine months after successful stenting, the mean SBP was 156.7 ± 24.1 mmHg; the 9 month restenosis rate was 14.4%. Conclusion : Based on the statistical modeling of these data and a priori established performance criteria, the co‐primary endpoints of 9 month reduction in blood pressure and in‐stent restenosis are proposed. The reduction in blood pressure will be analyzed as a continuous variable and will be compared to this performance goal. © 2011 Wiley‐Liss, Inc. 相似文献
88.
Abstract: Atopic dermatitis (AD) is a common chronic inflammatory type of eczema. The underlying cause of AD has not been established. Several studies have shown initial epidermal barrier dysfunction with subsequent immune activation as the underlying mechanism. Recently, in addition to its classical role in calcium homeostasis, vitamin D has been recognized for its effect on immunomodulation. Animal studies, case reports, and randomized clinical trials have suggested that vitamin D, through various mechanisms, may alleviate the symptoms of AD. The majority of these studies indicate an inverse relationship between the severity of atopic dermatitis and vitamin D levels. Furthermore, studies have shown that, in individuals with AD who are deficient in vitamin D, repletion of vitamin D results in decreased severity of disease. We present a review of the present literature that suggests a potentially significant role for vitamin D in the treatment of AD. 相似文献
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90.
Krishna A Dani Celestine Santosh David Brennan Donald M Hadley Keith W Muir 《Journal of cerebral blood flow and metabolism》2012,32(12):2114-2117
Hyperoxia during T2*-weighted magnetic resonance imaging (oxygen challenge imaging (OCI)) causes T2*-weighted signal change that is dependent on cerebral blood volume (CBV) and oxygen extraction fraction (OEF). Crossed cerebellar diaschisis (CCD), where CBV is reduced but OEF is maintained, may be used to understand the relative contributions of OEF and CBV to OCI results. In subjects with large hemispheric strokes, OCI showed reduced signal change in the contralesional cerebellum (P=0.027, n=12). This was associated with reduced CBV in contralesional cerebellum (P=0.039, n=9). CCD may be a useful model to determine the relative contribution of CBV to signal change measured by OCI. 相似文献