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1.
《Chronobiology international》2013,30(10):1146-1151
Diabetes mellitus is a chronic disease, which has an increasing trend all over the world. Type 2 diabetes constitutes 90% of all diabetes. It is associated with weight gain and insulin resistance. Research during recent years has suggested that shift work could be a risk factor of type 2 diabetes. Since shift work is becoming more common, it could contribute to the increasing trend of diabetes. In this systematic review, we have studied the potential association between shift work and type 2 diabetes. We have also reviewed studies on control of diabetes in relation to shift work.  相似文献   

2.
Alanine dehydrogenase (AlaDH) (E.C.1.4.1.1) is a microbial enzyme that catalyzes a reversible conversion of L-alanine to pyruvate. Inter-conversion of alanine and pyruvate by AlaDH is central to metabolism in microorganisms. Its oxidative deamination reaction produces pyruvate which plays a pivotal role in the generation of energy through the tricarboxylic acid cycle for sporulation in the microorganisms. Its reductive amination reaction provides a route for the incorporation of ammonia and produces L-alanine which is required for synthesis of the peptidoglycan layer, proteins, and other amino acids. Also, AlaDH helps in redox balancing as its deamination/amination reaction is linked to the reduction/oxidation of NAD+/NADH in microorganisms. AlaDH from a few microorganisms can also reduce glyoxylate into glycine (aminoacetate) in a nonreversible reaction. Both its oxidative and reductive reactions exhibit remarkable applications in the pharmaceutical, environmental, and food industries. The literature addressing the characteristics and applications of AlaDH from a wide range of microorganisms is summarized in the current review.  相似文献   

3.
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Massive anthropogenic land use changes are taking place in the tropics. These changes have not only jeopardized native biodiversity but also people. Environmental apathy, corruption, poor natural resource governance, poverty and lack of conservation funding remain formidable challenges for conservation biologists. Any meaningful success in tropical conservation will, hence, need active collaboration by the civil society, biologists, social scientists, lawyers, funding agencies, national and multinational corporations, governments and non-governmental organizations. Concerted research efforts are urgently needed to understand the imperiled tropical biodiversity.  相似文献   

4.
The ability of microorganisms to use polyethylene as a carbon source has only been recently established. This result has significance both from an environmental point of view, due to the accumulation of millions of tons of waste plastics every year, but also regarding the conservation of integrity for infrastructures incorporating this plastic. A number of microorganisms with the ability to grow on polyethylene have been isolated. The effects of these microorganisms on the physiochemical properties of this polymer have been described; these include changes in crystallinity, molecular weight, topography of samples and the functional groups found on the surface. Although the bio-degradation and bio-deterioration of polyethylene has been demonstrated by several researchers, the enzymes involved and mechanisms associated with these phenomena are still unclear. Nevertheless, it is recognized that both enzymatic and abiotic factors (such UV light) can mediate the initial oxidation of polyethylene chains, and given the chemical similarity between polyethylene and olefins it has been suggested that the metabolic pathways for degradation of hydrocarbons can be used once the size of polyethylene molecules decrease to an acceptable range for enzyme action (typically from 10 to 50 carbons). The long-range structure and morphology of polyethylene have shown important roles, with amorphous regions being more prone to microbial attack than crystalline ones. This review focuses on the recent hypotheses and experimental findings regarding the biodegradation of polyethylene.  相似文献   

5.
Polyomavirus inactivation has been studied since the 1950s when it became apparent that certain polio vaccines were contaminated with SV40. Relatively high temperatures (≥70 °C) are required to effect thermal inactivation of the polyomaviruses. The chemical inactivants that are effective (β-propiolactone, ethanol, sodium hydroxide, and formaldehyde) are those that have displayed efficacy for other small, non-enveloped viruses, such as the circoviruses. Low pH inactivation can be effective, especially at pH at or below 3 and at higher temperatures. Polyomaviruses are more resistant to UV-C irradiation than are other small non-enveloped viruses such as the parvoviruses and caliciviruses. The efficacy of photodynamic inactivation of polyomaviruses is very much dye-dependent, with toluidine blue, acridine orange, and methylene blue dyes being effective photosensitizers. Ionizing radiation can be effective, depending on the conditions employed and the inactivation matrix. Inactivation of the oncogenic properties of the polyomaviruses may require higher doses of inactivant than those required to inactivate infectivity. While the polyomaviruses are considered to be highly resistant to inactivation, the degree of resistance is dependent upon the specific approach under consideration. For certain approaches, such as UV-C and gamma-irradiation, the polyomaviruses appear to be more resistant than other small non-enveloped viruses.  相似文献   

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7.
Nanotechnology is the formation, running and use of operation at the nanomaterial size scale (1–100 nm). Nanoscale materials can also be obtained by biological synthesis materials via eco-friendly green chemistry based technique. Current development and numerous strategies involved in the green synthesis of nanoparticles were focussed. This review mainly focused on plants which include scientific name, family name, common name, plant parts, its characterization, size and shape of the nanoparticles. Plant extract which was done experimentally gives its various characterization which leads to the identification of compounds of different nano size and shape. Biosynthesis of gold nanoparticles is in different shapes like spherical, rod, cubic, triangle and also in different sizes. Various application and importance of gold nanoparticles in numerous fields were discussed. The mark of the review is to provide an overview of recent learning in biosynthesized nanoparticles, its characterization and their potential applications.  相似文献   

8.
Automation of the measurement of the physiological and behavioural parameters of livestock has become an important goal for both scientists and farmers. Accurate data and knowledge about farmed animals, especially in cattle breeding, are needed. Proper early diagnosis of a cow's health status in real time allows for preventing the development of infection, oestrus detection and leads to reduced environmental stress. Thus, it contributes to more effective herd management. Among the physiological parameters, body temperature and its fluctuations are key indicators of health and well-being in animals. Currently, along with the development of technical solutions and their implementation, increasingly more attention is being paid to the continuously measurement of body core and peripheral temperature in animals. Recently there has been an increased number of publications devoted to this subject. However, there is a need to systematise this knowledge as these studies have had different purposes, have been performed in various environmental conditions, and the measurements were taken using different methods and equipment. As such, the results obtained by the different authors often may not be comparable. For this reason, this paper has two main purposes: to present the most widely used continuous methods of peripheral and body core temperature measurement, and to show its references values which characterise the individual locations of the cattle body in thermoneutral ambient. An analysis of the professional publications regarding measurements of peripheral and deep body temperature led to the conclusion that these methods have high research and diagnostic potential. However, it is necessary to standardised research to enable better and more comparable results, including among others; different cattle groups, animal age, health and environmental conditions.  相似文献   

9.
Brassica species display enormous diversity and subsequently provide the widest assortment of products used by man from a single plant genus. Many species are important for agriculture, horticulture, in bioremediation, as medicines, soil conditioners, composting crops, and in the production of edible and industrial oils such as liquid fuels and lubricants. Many wild Brassica relatives possess a number of useful agronomic traits, including beneficial microbial endophytes that could be incorporated into breeding programs. Endophytes of Brassica, and/or their metabolites, have been demonstrated to improve and promote plant growth; increase yield; reduce disease symptoms caused by plant pathogens; reduce herbivory from insect pests; remove contaminants from soil; improve plant performance under extreme conditions of temperature and water availability; solubilise phosphate and contribute assimilable nitrogen to their hosts. Brassica napus (oilseed rape) and Brassica oleracea var. botrytis (broccoli and cauliflower) are the most economically important species of Brassica worldwide. These commercial crops are attacked by a wide range of pathogens and insect pests that are responsible for millions of dollars in lost revenue, with current control options offering little mitigation. No alternative control products are available for the Brassica industry, although it has been well documented in the literature that the use of endophytic microorganisms can offer beneficial traits to their host plants, including pest and disease resistance. The aim of this review is to describe the literature concerning beneficial microbial endophytes and their prospects to enhance or provide additional traits to their Brassica host species.  相似文献   

10.
Jong Won Yun 《Phytochemistry》2010,71(14-15):1625-1641
Obesity is associated with many diseases, particularly diabetes, hypertension, osteoarthritis, and heart disease. The obesity incidence has increased at an alarming rate in recent years, becoming a worldwide health problem, with incalculable social costs. Two different obesity-treatment drugs are currently on the market: orlistat, which reduces intestinal fat absorption via inhibiting pancreatic lipase; and sibutramine, an anorectic or appetite suppressant. Both drugs have hazardous side-effects, including increased blood pressure, dry mouth, constipation, headache, and insomnia. For this reason, a wide variety of natural materials have been explored for their obesity treatment potential. These are mainly complex products having several components with different chemical and pharmacological features. This review aimed to survey the literature covering natural products with anti-obesity activity and to review the scientific data, including experimental methodologies, active components, and mechanisms of action against obesity.  相似文献   

11.
Insight into the magnitude of muscle forces is important in biomechanics research, for example because muscle forces are the main determinants of joint loading. Unfortunately muscle forces cannot be calculated directly and can only be measured using invasive procedures. Therefore, estimates of muscle force based on surface EMG measurements are frequently used. This review discusses the problems associated with surface EMG in muscle force estimation and the solutions that novel methodological developments provide to this problem. First, some basic aspects of muscle activity and EMG are reviewed and related to EMG amplitude estimation. The main methodological issues in EMG amplitude estimation are precision and representativeness. Lack of precision arises directly from the stochastic nature of the EMG signal as the summation of a series of randomly occurring polyphasic motor unit potentials and the resulting random constructive and destructive (phase cancellation) superimpositions. Representativeness is an issue due the structural and functional heterogeneity of muscles. Novel methods, i.e. multi-channel monopolar EMG and high-pass filtering or whitening of conventional bipolar EMG allow substantially less variable estimates of the EMG amplitude and yield better estimates of muscle force by (1) reducing effects of phase cancellation, and (2) adequate representation of the heterogeneous activity of motor units within a muscle. With such methods, highly accurate predictions of force, even of the minute force fluctuations that occur during an isometric and isotonic contraction have been achieved. For dynamic contractions, EMG-based force estimates are confounded by the effects of muscle length and contraction velocity on force producing capacity. These contractions require EMG amplitude estimates to be combined with modeling of muscle contraction dynamics to achieve valid force predictions.  相似文献   

12.
《Gene》1997,192(1):135-140
An extensive and representative strain collection of serogroup A Neisseria meningitidis was established. These bacteria were obtained from different endemic and epidemic/pandemic sources and include strains from diseased patients and healthy carriers. The genetic relationships of the bacteria were defined by multi-locus enzyme electrophoresis and sequence polymorphisms of genetically variable antigens have been analyzed in closely-related groupings. The results are interpreted as reflecting a balance of recombination events, which disrupt clonal relationships, and sequential bottlenecks, which purify the bacterial population of genetic variants during epidemic spread.  相似文献   

13.
Milk-derived bioactive peptides have been identified as potential ingredients of health-promoting functional foods. These bioactive peptides are targeted at diet-related chronic diseases especially the non-communicable diseases viz., obesity, cardiovascular diseases and diabetes. Peptides derived from the milk of cow, goat, sheep, buffalo and camel exert multifunctional properties, including anti-microbial, immune modulatory, anti-oxidant, inhibitory effect on enzymes, anti-thrombotic, and antagonistic activities against various toxic agents. Majority of those regulate immunological, gastrointestinal, hormonal and neurological responses, thereby playing a vital role in the prevention of cancer, osteoporosis, hypertension and other disorders as discussed in this review. For the commercial production of such novel bioactive peptides large scale technologies based on membrane separation and ion exchange chromatography methods have been developed. Separation and identification of those peptides and their pharmacodynamic parameters are necessary to transfer their potent functional properties into food applications. The present review summarizes the preliminary classes of bioactive milk-derived peptides along with their physiological functions, general characteristics and potential applications in health-care.  相似文献   

14.
X.F. Lou  J. Nair 《Bioresource technology》2009,100(16):3792-3798
Municipal solid waste is a significant contributor to greenhouse gas emissions through decomposition and life-cycle activities processes. The majority of these emissions are a result of landfilling, which remains the primary waste disposal strategy internationally. As a result, countries have been incorporating alternative forms of waste management strategies such as energy recovery from landfill gas capture, aerobic landfilling (aerox landfills), pre-composting of waste prior to landfilling, landfill capping and composting of the organic fraction of municipal solid waste. As the changing global climate has been one of the major environmental challenges facing the world today, there is an increasing need to understand the impact of waste management on greenhouse gas emissions. This review paper serves to provide an overview on the impact of landfilling (and its various alternatives) and composting on greenhouse gas emissions taking into account streamlined life cycle activities and the decomposition process. The review suggests greenhouse gas emissions from waste decomposition are considerably higher for landfills than composting. However, mixed results were found for greenhouse gas emissions for landfill and composting operational activities. Nonetheless, in general, net greenhouse gas emissions for landfills tend to be higher than that for composting facilities.  相似文献   

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16.
The reaction of LiCCMe with [(Dipnacnac)MgI(OEt2)] (Dipnacnac = [(DipNCMe)2CH], Dip = 2,6-diisopropylphenyl) afforded [{(Dipnacnac)MgCCMe}2] 1 in good yield. Treatment of 1 with AlH3·NMe3 in toluene under reflux afforded a low yield of the novel imido aluminium magnesium hydride compound [{(AlH)(AlH2)3(NDip)3}2Mg] 2. The latter compound features a central Mg2+ ion that is coordinated via hydride ligands to two monoanionic [(AlH)(AlH2)3(NDip)3] fragments. The compounds have been characterised by 1H and 13C NMR spectroscopy, IR spectroscopy and the crystal structures of 1 and 2·4C7H8 have been determined.  相似文献   

17.
This article reviews recent advances achieved during recent years on various aspects of antibody humanization theories and techniques. Common methods for producing humanized antibodies including framework-homology-based humanization, germline humanization, complementary determining regions (CDR)-homology-based humanization and specificity determining residues (SDR) grafting, as well as advantages and disadvantages of each of these methods and their applications are discussed.  相似文献   

18.
This paper reviews the interactions of insects with food packaging, and measures which may be taken to limit damage.  相似文献   

19.
BackgroundTesticular cancer (TC) is the most common cancer in the 25–40 age group, with peak morbidity at around 30 years of age. It is a period of highest productivity, when sexual sphere is an important aspect of life. The disease, invasive treatment and its consequences interfere with this sphere.AimThe aim of this paper was to review the most recent studies on the sexual functioning of patients treated for testicular cancer and their partners published in English language scientific journals in the period of 1989–2010.ResultsNumerous studies report that men cured from testicular cancer are at risk of sexual disorders. Agents of psychological nature play an important role in the occurrence and persistence of sexual dysfunctions. Being in permanent relationship is a protective factor, while single persons are marked with particular predisposition to such dysfunctions. Sexual and marital satisfaction of TC survivors and their partners are mutually correlated.ConclusionWith a growing number of TC survivors, a thorough investigation is required into their sexuality, both in an individual and dyadic dimension, so as to improve the quality of life of the affected young men, who take on their new social and professional roles in the period of highest reproductiveness.  相似文献   

20.
Lignans are a group of compounds consisting of dimers of phenyl propane units. They are found in diverse forms distributed in a variety of plants. Sesame lignans in particular are obtained from Sesamum indicum, a highly prized oilseed crop cultivated widely in many countries in the east. The plant is the main source of clinically important antioxidant lignans such as sesamin, sesamolin, sesaminol and sesamol. These lignans exhibit antihypertensive, anticancerous and hypocholesterolemic activities as well especially in humans due to which they have become compounds of tremendous research interest in recent times. Sesamin is synthesized from shikimic acid through phenylpropanoid pathway and metabolised into enterolignans which play a pivotal role in protection against several hormone related diseases. In this paper we present an overview of current status of research on sesame lignans with respect to the analytical methods employed, the biological activities and biosynthesis of sesame lignans.  相似文献   

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