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1.
Electrocardiogram (ECG) signal gives a lot of information on the physiology of heart. In reality, noise from various sources interfere with the ECG signal. To get the correct information on physiology of the heart, noise cancellation of the ECG signal is required. In this paper, the effectiveness of extended Kalman smoother (EKS) with the differential evolution (DE) technique for noise cancellation of the ECG signal is investigated. DE is used as an automatic parameter selection method for the selection of ten optimized components of the ECG signal, and those are used to create the ECG signal according to the real ECG signal. These parameters are used by the EKS for the development of the state equation and also for initialization of the parameters of EKS. EKS framework is used for denoising the ECG signal from the single channel. The effectiveness of proposed noise cancellation technique has been evaluated by adding white, colored Gaussian noise and real muscle artifact noise at different SNR to some visually clean ECG signals from the MIT-BIH arrhythmia database. The proposed noise cancellation technique of ECG signal shows better signal to noise ratio (SNR) improvement, lesser mean square error (MSE) and percent of distortion (PRD) compared to other well-known methods.  相似文献   
2.
The role that free radicals in general and oxygen radicals in particular play in carcinogenesis has attracted considerable attention in recent years. The oxygen radicals are undesirable but inevitable products of aerobic metabolism in the normal living cell. The cellular antioxidant defense system maintains an appropriate balance between necessary oxidative events and those that are excessive. When this critical balance cannot be maintained because of the overloading of the cellular redox system, oxygen radicals can induce cell damage. They can influence carcinogenesis by inducing DNA damage from direct oxidation or indirectly from DNA-binding products of lipid peroxidation. Oxygen radicals can induce conformational changes in the plasma membrane by lipid peroxidation and protein degradation, thus influencing membrane-associated cellular activities. They are capable of affecting membrane-bound protein kinases, growth factors and their receptors, and, therefore, signal transduction and oncogene activation. Thus, the oxygen radicals can have a major influence on oncogenes and oncogenesis.  相似文献   
3.
Recent evidence suggests that a variety of hypothalamic neuropeptides may mediate interneuronal communication to coordinate diverse neuroendocrine and behavioral functions. In this work, we describe the effects of neuropeptide Y (NPY) on feeding and sexual behaviors. We observed that central administration of bolus NPY stimulated a robust, dose-related feeding response in satiated male and female rats. Continuous NPY receptor activation also evoked dose-related, intermittent feeding in a manner normally observed during nocturnal feeding. It appears that the paraventricular nucleus in the hypothalamus may be the primary site of NPY action because the anticipated reciprocal changes in NPY concentrations, in response to food deprivation followed by ad libitum food intake, occurred only in this site. Additional findings revealed that NPY-induced feeding may follow either substantial reduction or complete restraint of an inhibitory influence on feeding mediated by alpha 2-adrenoreceptor systems in satiated rats. Further, NPY was found to suppress male and female sexual behaviors. The suppressive effects on sexual behavior were apparent prior to or at the time of the onset of feeding after NPY administration. These observations may provide a neurochemical basis for clinical and animal studies on disorders of feeding associated with diminished reproductive functions.  相似文献   
4.
Vegetarians may have subtle nutritional deficiencies which have been related to the occurrence of an unrecognized malabsorption syndrome. The excess phytate content in cereals, nuts, legumes and oilseeds which represent the mainstay of their food intake, seems to play a central role in the pathogenesis of this malabsorption syndrome as an inverse relationship has been shown to link the phytate content of the diet with the intestinal absorption of trace minerals and proteins. We postulate that manipulating the endogenous digestive microflora of subjects on a vegetarian diet through administering probiotic lactic bacteria would represent an innovative tool to counteract the occurrence of the malabsorption syndrome dependent on the high phytate content of their diet. Even though there are no data about the composition of endogenous digestive microflora in subjects on a vegetarian diet, we expect that probiotic lactobacilli can interact with or affect distinct yet interrelated components within the intestinal milieu, such as epithelial cells, enteric flora, and/or mucosal immune cells. This would ultimately translate into the correction of the unregulated mechanisms implicated in the altered intestinal absorption of trace metals and proteins commonly seen in vegetarians. Clinical experience with probiotic therapy of patients with inflammatory bowel disease fully agrees with this view. One additional point of interest is that probiotic lactobacilli, and other species of the endogenous digestive microflora as well, are an important source of the enzyme phytase which catalyses the release of phosphate from phytate and hydrolyses the complexes formed by phytate and metal ions or other cations, rendering them more soluble ultimately improving and facilitating their intestinal absorption. The regular intake of probiotic preparation, may represent a cheap and safe tool in order to convert a diet with a low potential for bioavailability of trace minerals and proteins, such as the vegetarian diet, into a diet with a high bioavailability potential. The benefit of such an approach would not be restricted to vegetarians.  相似文献   
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6.
This issue reports selected results from a comprehensive study of infant and child mortality based on the National Family Health Survey data. The analysis distinguishes between neonatal, postneonatal, infant and child mortality since mortality and its causes vary considerably among children of different ages. Hazard regression analysis was used to estimate the effects of each individual variable as the factors that affect infant and child mortality tend to be correlated with each other. The study involves adjusted effects of selected socioeconomic and demographic characteristics on neonatal, postneonatal, infant, and child mortality for children born during the survey. Short birth intervals have a great effect on infant and child mortality. A previous birth interval of less than 24 months increases child mortality by about 67%. Neonatal mortality is highest among children of very young mothers. Child mortality is higher for girls in all states except Tamil Nadu, Kerala, and Goa. Seven groups of children who are especially vulnerable to infant and child mortality were identified. Thus, intervention programs, such as efforts to provide supplemental nutrition and basic immunization to pregnant mothers, infants and young children need to focus on these high-risk groups. Results for many states show elevated mortality rates for girls after the neonatal period. Family health programs aimed at overall improvement in mortality levels should pay attention to providing basic health care and supplemental nutrition to girls.  相似文献   
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8.
Exposure to nanosilver found in food‐ and cosmetics‐related consumer products is of public concern because of the lack of information about its safety. In this study, two widely used in vitro cell culture models, human liver HepG2 and colon Caco2 cells, and the flow cytometric micronucleus (FCMN) assay were evaluated as tools for rapid predictive screening of the potential genotoxicity of nanosilver. Recently, we reported the genotoxicity of 20 nm nanosilver using these systems. In the current study presented here, we tested the hypothesis that the nanoparticle size and cell types were critical determinants of its genotoxicity. To test this hypothesis, we used the FCMN assay to evaluate the genotoxic potential of 50 nm nanosilver of the same shape, composition, surface charge and obtained from the same commercial source using the same experimental conditions and in vitro models (HepG2 and Caco2) as previously tested for the 20 nm silver. Results of our study show that up to the concentrations tested in these cultured cell test systems, the smaller (20 nm) nanoparticle is genotoxic to both the cell types by inducing micronucleus (MN). However, the larger (50 nm) nanosilver induces MN only in HepG2 cells, but not in Caco2 cells. Also in this study, we evaluated the contribution of ionic silver to the genotoxic potential of nanosilver using silver acetate as the representative ionic silver. The MN frequencies in HepG2 and Caco2 cells exposed to the ionic silver in the concentration range tested are not statistically significant from the control values except at the top concentrations for both the cell types. Therefore, our results indicate that the ionic silver may not contribute to the MN‐forming ability of nanosilver in HepG2 and Caco2 cells. Also our results suggest that the HepG2 and Caco2 cell cultures and the FCMN assay are useful tools for rapid predictive screening of a genotoxic potential of food‐ and cosmetics‐related chemicals including nanosilver. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.  相似文献   
9.
Purpose In women the relationship between myotonic dystrophy type I and fertility remains controversial. The objective of this study was to evaluate the ovarian reserve, ovarian response to stimulation and oocyte quality in these patients. Materials and methods We compared 15 myotonic dystrophy type I patients with 39 age matched controls with isolated male factor infertility necessitating ICSI. Results All parameters of ovarian reserve (day 3 FSH and E2, antral follicle count and delta E2) were significantly better in the controls. Despite having significantly lower doses of gonadotrophin, the control group attained a higher number of retrieved oocyte–cumulus complexes (p < 0.04). Analysis of cytoplasmic and extracytoplasmic dysmorphism did not reveal any difference between the two groups. Fertilisation rate and top grade embryos on day 3 were similar in both groups. Conclusion The present study suggests that though women with myotonic dystrophy type I have a reduced ovarian reserve and respond poorly to controlled ovarian stimulation, there is no impact on oocyte and embryo quality. Hence suggesting that successful ART is feasible with appropriate selection in women with mild myotonic dystrophy. Capsule Women with myotonic dystrophy type I have reduced ovarian reserve and respond poorly to controlled ovarian stimulation, though there is no impact on oocyte quality.  相似文献   
10.
Objective To determine the frequency of cervical pathology and the incidence of cervical neoplasia in women presenting with PCB at the colposcopy clinic with negative cytology. Design A retrospective study. Setting A district general hospital. Population Eighty-seven women with postcoital bleeding and negative cytology were seen in the colposcopy unit during 1 January 2003 to 31 December 2005. Methods Women were identified from computer records and details were extracted from the case notes. Main outcome measure Histopathological diagnosis. Results Six women (6.9%) had cervical intraepithelial neoplasia. There were no cases of invasive cancer. Thus in our study 6.9% women with postcoital bleeding had abnormal histology even though they had normal smears. Other identifiable causes were cervical polyp (12.5%), ectopy (33.6%) and Chlamydia (2.3%). No pathology was found in 50% of women. Conclusion Women with postcoital bleeding even with normal smears appear to be at much greater risk of cervical neoplasia than the general population. Unfortunately there is no general consensus for management of these patients. Hence further research is needed to standardise the management of women with PCB. Patients should be reassured that in vast majority of cases no serious pathology is detected.  相似文献   
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