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Background

Transcranial Doppler Ultrasound (TCD) is a sensitive, real time tool for monitoring cerebral blood flow velocity (CBFV). This technique is fast, accurate, reproducible and noninvasive. In the setting of congenital heart surgery, TCD finds application in the evaluation of cerebral blood flow variations during cardiopulmonary bypass (CPB).

Methodology

We performed a search on human studies published on the MEDLINE using the keyword "trans cranial Doppler" crossed with "pediatric cardiac surgery" AND "cardio pulmonary by pass", OR deep hypothermic cardiac arrest", OR "neurological monitoring".

Discussion

Current scientific evidence suggests a good correlation between changes in cbral blood flow and mean cerebral artery (MCA) blood flow velocity. The introduction of Doppler technology has allowed an accurate monitorization of cerebral blood flow (CBF) during circulatory arrest and low-flow CPB. TCD has also been utilized in detecting cerebral emboli, improper cannulation or cross clamping of aortic arch vessels. Limitations of TCD routine utilization are represented by the need of a learning curve and some experience by the operators, as well as the need of implementing CBF informations with, for example, data on brain tissue oxygen delivery and consumption.

Conclusion

In this light, TCD plays an essential role in multimodal neurological monitorization during CPB (Near Infrared Spectroscopy, TCD, processed electro encephalography) that, according to recent studies, can help to significantly improve neurological outcome after cardiac surgery in neonates and pediatric patients.  相似文献   

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Lower screening uptake could impact cancer survival in rural areas. This systematic review sought studies comparing rural/urban uptake of colorectal, cervical and breast cancer screening in high income countries. Relevant studies (n = 50) were identified systematically by searching Medline, EMBASE and CINAHL. Narrative synthesis found that screening uptake for all three cancers was generally lower in rural areas. In meta-analysis, colorectal cancer screening uptake (OR 0.66, 95 % CI = 0.50−0.87, I2 = 85 %) was significantly lower for rural dwellers than their urban counterparts. The meta-analysis found no relationship between uptake of breast cancer screening and rural versus urban residency (OR 0.93, 95 % CI = 0.80–1.09, I2 = 86 %). However, it is important to note the limitation of the significant statistical heterogeneity found which demonstrates the lack of consistency between the few studies eligible for inclusion in the meta-analyses. Cancer screening uptake is apparently lower for rural dwellers which may contribute to poorer survival. National screening programmes should consider geography in planning.  相似文献   

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Abstract

This systematic review aimed to discuss the effects of arginine on caries-related microorganisms in different in vitro biofilm models. The eligibility criteria were in vitro studies that evaluated the effect of arginine at different concentrations on caries-related microorganisms using biofilm models. Eighteen studies published between 2012 and 2019 were included. Different bacterial species were studied. Seventeen studies (94.4%) achieved a low risk of bias and only one showed a medium risk of bias. The studies showed that arginine is a promising approach for the ecological management of dental caries. The focus of this review was to evaluate the effects of arginine on microorganisms involved in the mechanism of dental caries.  相似文献   

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Paraneoplastic cerebellar degeneration is part of a rare spectrum of neurological syndromes whereby gynaecological, lung or breast cancers present primarily with neurological manifestations. The presence of onconeural antibodies and PET scanning help in the challenging diagnosis of these conditions but despite the treatment of the primary cancer, the prognosis for the neurological symptoms is poor.  相似文献   

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Worldwide, food waste is one of the prime issues threatening food security and the Kingdom of Saudi Arabia (KSA) is not an exception. With 427 kg of food wasted per capita per year, the country ranks among the top food wasters. Ironically, the Kingdom has limited arable lands and scarce water resources to support mass-scale agriculture and to feed its increasing population, KSA relies heavily on imports and subsidized food to meet needs. Yet, food is wasted at restaurants, caterers, cafeterias and, especially, by households such that food waste is the single-largest component of the landfills. The review article is based on the grey and scientific literature published in the English and Arabic languages on the issue of food waste in Saudi Arabia. Information sources like Web of knowledge, online resources and the databases available through the King Saud University, Saudi Arabia were accessed and used to collect information on food waste, its social, cultural, economic and environmental impacts and related topics. Since food items and groceries are abundantly available to all living in KSA and they are highly subsidized, the residents take food for granted. According to a recent survey, about 78% of food purchased in KSA is discarded each week in order to make room for new groceries. The factors responsible for food waste include: lack of awareness; and insufficient and inappropriate planning when shopping. Food waste in restaurants, celebrations, social events and occasions are enormous. Waste is common in festivals and special events where the customs is to provide more food than required. There is a need to change society’s food culture, particularly among the women and the youth, as they are largest segment of the society and the prime food wasters. The analysis of the factors responsible for food waste, identified in this article suggests a “Stop Wasting Food” campaign should be launched. It is also recommended to determine and activate the role of extension education to reduce food waste in the KSA through vibrant capacity building programs for youth and women, in particular, and society in general.  相似文献   

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On the south west coast of India, there is an extensiveestuarine system of backwaters, of which Vembanad Lake is the largest. The backwaters of Kerala support as much biological productivity and diversity as tropical rain forests. They are responsible for the rich fisheries potential of Kerala. Cochin backwaters situated at the tip of the northern Vembanad lake is a tropical positive estuarine system extending between 9° 40 and 10° 12N and 76° 10' and 76° 30 E with its northern boundary at Azheekode and southern boundary at Thannirmukham bund. The lake has a length of 80 km and the width varies between 500 and 4000 m. A channel, about 450 m wide at Cochin gut and another at Azheekode, make permanent connections with the Arabian Sea. The depth of the estuary varies considerably. While the shipping channels are maintained at a depth of 10–13 m, the major portion of the estuary has a depth range of 2–7 m. Water from two major rivers viz., Periyar and Muvattupuzha drain into this estuary. During south west monsoon, the estuary is virtually converted into a freshwater basin even in areas around barmouth where salt water penetration occurs below 5 m depth only. The major hydrological variable in the Cochin backwaters is salinity, similar to the situations encountered in estuaries with a gradual declension of salinity from 30 at the entrance of the estuary to 0.2 at the point of entry of the rivers. Salinity gradient in the Cochin backwaters supports diverse species of flora and fauna depending on their capacity to tolerate oligohaline, mesohaline or marine conditions. Low lying swamps and tidal creeks, dominated by sparse patches of mangroves with their nutrient rich physical environment, support larvae and juveniles of many economically important species. Backwaters also act as nursery grounds of commercially important prawns and fishes. The fields around the backwater are suitable for aquaculture. These areas support traditional, seasonal and perennial prawn fishery. The changes in the hydrology controlled by the seasons play an important role in regulating the migrant fauna of the estuary. The Cochin backwater supports a well established endemic fauna. The nutrients and pollutants introduced into the estuary control to a great extent the distribution and abundance of less tolerant species in ecologically sensitive areas in the backwaters. Cochin backwaters, widely regarded as one of the polluted estuaries in India, receive contaminated freshwater inputs and discharges of effluents and partially treated sewage from many points throughout its tidally mixed zone. Recently, changes brought about in the estuary like reclamation and consequent shrinkage of the backwaters and the discharge of pollutants have made an adverse impact on the potential of aquatic ecosystems that used to support high levels of bioproductivity and biodiversity. The construction of Thannirmukham bund and Thottapally spillway to prevent salt water penetration into the paddy fields during pre-monsoon has led to serious ecological problems by interrupting the natural ebb and flow of tides. The hydrography, floral and faunal composition – its spatial and temporal variation plus assessments of the impact of the anthropogenic activities are presented in this review. An attempt to critically evaluate the status of the estuary from the biological and pollutional stand point is also done.  相似文献   

8.
Ne'eman  Gidi  Goubitz  Shirrinka  Nathan  Ran 《Plant Ecology》2004,171(1-2):69-79

Fire is known to be a major factor in shaping plants and vegetation worldwide. Many plant traits have been described as adaptations for surviving fire, or regenerating after it. However, many of the traits are also advantageous for overcoming other disturbances. The fact that fire in the Mediterranean Basin has been almost exclusively of anthropogenic origin, and thus is of short duration in an evolutionary time scale, cast doubt on the possibility that fire can act as a selective force in the Mediterranean Basin. Our aim here is to review the ecological advantages of Pinus halepensis traits and their possibility to be selected by fire. The non-self pruning of cones and branches, and the high resin content increase the probability of canopy fires and consequent death of P. halepensis trees. Post-fire regeneration of P. halepensis depends totally upon its canopy-stored seed bank. The seedlings grow quickly and they first reproduce at an early age. Young reproductive trees function first as females with a high percentage of serotinous cones. Thus, young P. halepensistrees allocate many resources to seed production, reducing their `immaturity risk' in a case of an early successive fire. The proportion of serotinous cones is higher in post-fire naturally regenerating stands than in unburned stands, and seeds from serotinous cones germinate better under simulated post-fire conditions. The extremely high pH of the ash-bed under the burned canopies creates the post-fire regeneration niche of P. halepensis exactly under their parent trees. All these traits are advantageous for post-fire regeneration, but could they also be selected during the time scale of anthropogenic fires in the Mediterranean Basin? Pinus halepensis is a relatively short living tree with almost no recruitment under forest canopy. The longest estimated fire-return interval and generation length are about 125 years. The earliest solid evidence for the first hominid-controlled fire in the Mediterranean basin is 780,000 years ago, and thus the estimated number of post-fire generations is 6240. We suggest that such a number of generations is sufficient for the selection and radiation of fire adaptive traits in P. halepensis.

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A comprehensive knowledge of the thoracic shape and kinematics is essential for effective risk prevention, diagnose and proper management of thoracic disorders and assessment of treatment or rehabilitation strategies as well as for in silico and in vitro models for realistic applications of boundary conditions.After an extensive search of the existing literature, this study summarizes 45 studies on in vivo thoracic kyphosis and kinematics and creates a systematic and detailed database. The thoracic kyphosis over T1–12 determined using non-radiological devices (34°) was relatively less than measured using radiological devices (40°) during standing. The majority of kinematical measurements are based on non-radiological devices. The thoracic range of motion (RoM) was greatest during axial rotation (40°), followed by lateral bending (26°), and flexion (21°) when determined using non-radiological devices during standing. The smallest RoM was identified during extension (13°). The lower thoracic level (T8–12) contributed more to the RoM than the upper (T1–4) and middle (T4–8) levels during flexion and lateral bending. During axial rotation and extension, the middle level (T4–8) contributed the most. Coupled motion was evident, mostly during lateral bending and axial rotation. With aging, the thoracic kyphosis increased by about 3° per decade, whereas the RoM decreased by about 5° per decade for all load directions. These changes with aging mainly occurred in the lower region (T6–12). The influence of sex on thoracic kyphosis and the RoM has been described as partly contradictory. Obesity was found to decrease the thoracic RoM. Studies comparing standing, sitting and lying reported the effect of posture as significant.  相似文献   

11.
ObjectiveThe prevalence of depression in oncological patients is 3, 4-fold compared to the general population. However, the specific risk factors for these prevalence rates are not fully understood.MethodsA systematic literature review was conducted in nine electronic databases between 2005 and 2020. The quality of the eligible studies was appraised by two persons using the adapted 11-items Downs and Black checklist.ResultsAmong 2010 potentially relevant articles, 40 studies were eligible, with 27 studies of high quality and 13 studies of moderate quality. A total of 156 factors associated with depression were identified which were clustered into somatic, psychological, social and sociodemographic factors. Pre-existing depression and personality factors were the most consistent associated factors with depression in cancer patients, while for most somatic and treatment-related factors only modest associations were found.ConclusionsGrouped as bio-psycho-social associated factors, somatic factors showed a modest influence, whereas social relationship (support) and previous depression are unequivocally significantly associated with depression.  相似文献   

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Water homeostasis during fetal development is of crucial physiologic importance. It depends upon maternal fetal fluid exchange at the placenta and fetal membranes, and some exchange between fetus and amniotic fluid can occur across the skin before full keratinization. Lungs only grow and develop normally with fluid secretion, and there is evidence that cerebral spinal fluid formation is important in normal brain development. The aquaporins are a growing family of molecular water channels, the ontogeny of which is starting to be explored. One question that is of particular importance is how well does the rodent (mouse, rat) fetus serve as a model for long-gestation mammals such as sheep and human? This is particularly important for organs such as the lung and the kidney, whose development before birth is very much less in rodents than in the long-gestation species.  相似文献   

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BACKGROUND: Primary central mucoepidermoid carcinoma of jaws is a rare lesion comprising 2-3% of all mucoepidermoid carcinomas reported in literature. CASE PRESENTATION: The case presented here illustrates the hypothesis that its specific pathogenesis is unknown. CONCLUSIONS: Mucoepidermoid carcinoma of the jaw is a rare tumour of unknown aetiology. Although about a 100 cases has been reported in literature, the speculation on its aetiopathogenesis has mainly centred on the pluripotential capabilities of the epithelial lining of odontogenic cysts.  相似文献   

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Water contamination by various recalcitrant organic aromatic compounds is an emerging environmental issue that is increasingly attracting the attention of environmental scientists. A great majority of these recalcitrant pollutants are industrial wastes, textile dyes, pharmaceuticals, hormones, and personal care products that are discharged into wastewater. Not surprisingly, various chemical, physical, and biological strategies have been proposed and developed to remove and/or degrade these pollutants from contaminated water bodies. Biological approaches, specifically using oxidoreductase enzymes (such as peroxidases and laccases) for pollutant degradation are a relatively new and a promising research area that has potential advantages over other methods due to their higher efficiency and the ease of handling. This review focuses on the application of different classes of oxidoreductase enzymes to degrade various classes of organic pollutants. In addition to classifying these enzymes based on structural differences, the major factors that can affect their remediation ability, such as the class of peroxidases employed, pH, molecular structure of the pollutant, temperature, and the presence of redox mediators are also examined and discussed. Interestingly, a literature survey combined with our unpublished data suggests that “peroxidases” are a very heterogeneous and diverse family of enzymes and have different pH profiles, temperature optima, thermal stabilities, requirements for redox mediators, and substrate specificities as well as varying detoxification abilities. Additionally, remediation of real-life polluted samples by oxidoreductases is also highlighted as well as a critical look at current challenges and future perspectives.  相似文献   

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Metastasis to the internal auditory canal from breast carcinoma is extremely rare and difficult to diagnose. It radiologically mimics vestibular schwannoma and can occur as a first manifestation of systemic relapse after a long disease-free interval in patients previously treated for early breast cancer. The diagnosis is usually made retrospectively and the optimal management of such metastasis following complete resection remains undefined.  相似文献   

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Fermenter control has been an active area of research and has attracted more attention in recent years. This is due to the new developments in other related areas which can be exploited to overcome the inherent difficulties in fermenter control. Beginning with conventional regulatory control of operating variables such as temperature, pH and dissolved oxygen concentration, research in fermenter control has undergone significant changes including the recent neural network based approaches. The objective of the paper is to focus the attention of the researchers to the developments in the control of batch, fed-batch and continuous fermenters over the past few years.  相似文献   

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Global pollinator declines and land-use change can lead to pollination limitation with implications for agricultural productivity. Hand pollination is used in agricultural production as a technique to manually pollinate crops. But the prevalence of hand pollination, as well as benefits and costs, remain unknown. We systematically reviewed the literature for examples, methods, drivers, and economic motivations of hand pollination. Furthermore, we discuss the risks, constraints, and opportunities of hand pollination. We found evidence for 20 hand-pollinated crops, including minor but also economically important crops (e.g. apple, oil palm, cacao). The lack of pollinators was the most important reason for the application of hand pollination (50% of crops), while insufficient proportion or proximity of pollinizers (8% of crops) and skewed sex ratio or dichogamy (8% of crops) were second most important. The main economic motivations for practicing or recommending hand pollination were to increase fruit set, and/or fruit quality (78% of crops). Hand pollination is practiced in large- and small-scale farming, home gardens, and greenhouses. Opportunities of hand pollination are the control of pollen origin and quantity, pollination timing and frequency as well as independence from environmental fluctuations. Farmers can increase yields, improve fruit quality, avoid fruit abortion, increase employment, and secure subsistence food. The main constraints of hand pollination are high labor inputs, high material costs, and required skills. Major risks of hand pollination include management ignoring pollinator conservation, high food prices, over-pollination, labor accidents, and unfair labor. We conclude that in the face of global change, hand pollination allows improved control of pollination and is likely to increase in importance. The benefits of hand pollination need to outweigh the costs and fair labor is essential. Altogether, hand pollination can be a valuable tool for crop systems where pollinators are absent or are not reliable for sustaining high-quality crop production.  相似文献   

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PurposeTo review the methodologies used to assess muscle co-contraction (MCo) with surface electromyography (sEMG) during gait in people with neurological impairment.MethodsThe Scopus (1995–2013), Web of Science (1970–2013), PubMed (1948-2013) and B-on (1999–2013) databases were searched. Articles were included when sEMG was used to assess MCo during gait in people with impairment due to central nervous system disorders (CNS).ResultsNineteen articles met the inclusion criteria and most studied people with cerebral palsy and stroke. No consensus was identified for gait assessment protocols (surfaces, speed, distance), sEMG acquisition (electrodes position), analysis of sEMG data (filters, normalisation techniques) and quantification of MCo (agonist-antagonist linear envelopes overlapping or agonist-antagonist overlapping periods of muscles activity, onset delimited).ConclusionGiven the wide range of methodologies employed, it is not possible to recommend the most appropriate for assessing MCo. Researchers should adopt recognized standards in future work. This is needed before consensus about the role that MCo plays in gait impairment in neurological diseases and its potential as a target for gait rehabilitation can be determined.  相似文献   

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