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Throughout the last century the increasing human activities in Antarctic region, particularly research expeditions, fishing, and tourism amplified the risk of oils spills at these high latitudes of the meridional hemisphere. A number of studies have been focused on chronic hydrocarbon contamination near Antarctic research stations revealing the presence and persistence of these human-derived contaminants. Marine ship-source oil spills in Antarctic region can have significant impacts on the marine environment. The key factors to effectively fight oil spills are a careful selection and proper use of the equipment and materials best suited to the critical local conditions. Despite the significant advances in the field of environmental recovery after an “oil spill” episode, research has recently shown that the usual techniques are often less effective than expected. This issue become much more relevant in the Antarctic case, not only for the incomparable environmental value of the Antarctic region but also for the extreme environmental conditions and the great distances from properly equipped centers, that make unfeasible sending naval vessels. Scope of the STRANgE Project is the preliminary design of a prototype floating platform, parachutable by plane, able to intervene as quickly as possible for the containment, removal and treatment/storage of the oil slick. New sorbent nanostructured materials and specialized Antarctic bacteria applications constitute the main innovations of this Project.  相似文献   

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The resurgence and spread of antimalarial drug resistance is one of the causes of the worldwide increase of malaria. In Colombia, uncomplicated Plasmodium falciparum malaria has been treated with a combination of amodiaquine (AQ) and sulfadoxine/pyrimethamine (SP) since 2000. The efficacy of these two antimalarials was evaluated after the implementation of the new malaria treatment scheme. In the municipalities of El Charco and Tumaco (Nari?o) on the Pacific Coast region, the standard PAHO protocol was used to evaluate antimalarial efficacy in areas of low to moderate malaria transmission. Patients were randomly allocated to treatment regime in two cities of Nari?o, El Charco (n = 48) and Tumaco (n = 50). After 14 days none of El Charco patients presented therapeutic failure to either antimalarial. However, in Tumaco after 28 days, 12 of 24 (95% CI: 30.6-69.4) patients presented AQ treatment failure while 4 of 26 (95% CI: 5.1-33.1) patients had SP treatment failure. The high level of AQ treatment failure in Tumaco was unexpected because it had been introduced only recently as an antimalarial treatment in Colombia. The results suggest that the use of the current dose of AQ in combination with SP will be therapeutically useful for less time than expected. Use of combined therapies is a key strategy to delay antimalarial resistance. Unfortunately, its success depends on the efficacy of antimalarial drugs individually.  相似文献   

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Niosomes have been claimed to enhance intestinal absorption and to widen the absorption window of acidic drugs. This was reported after monitoring the intestinal absorption in situ. Accordingly, the aim of this work was to investigate the effect of niosomal encapsulation on intestinal absorption and oral bioavailability of nateglinide. This was conducted with the goal of correlation between in situ intestinal absorption and in vivo availability. The drug was encapsulated into proniosomes. The niosomes resulting after hydration of proniosomes were characterized with respect to vesicle size and drug entrapment efficiency. The in situ rabbit intestinal absorption of nateglinide was monitored from its aqueous solution and niosomes. Streptozotocin was used to induce diabetes in albino rats which were then used to assess the hypoglycemic effect of nateglinide after oral administration of aqueous dispersion and niosomal systems. The prepared vesicles were in the nanoscale with the recorded size being 283?nm. The entrapment efficiency depended on the pH of the formulation. The in situ intestinal absorption reflected non-significant alteration in the membrane transport parameters of the drug after niosomal encapsulation compared with the free drug solution. In contrast, niosomes showed significant improvement in the rate and extent of the hypoglycemic effect compared with the unprocessed drug. This discrepancy can be attributed to different transport pathway for the drug after niosomal inclusion with the vesicles undergoing translymphatic transport which can minimize presystemic metabolism. However, this requires confirmatory investigations. In conclusion niosomes can enhance oral bioavailability of nateglinide with the absorption being through nontraditional pathway.  相似文献   

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正Dear Editor,Here,we report the risk factors for severe hand-foot-mouth disease(HFMD)determined by our case-controlstudy.Our findings could help disease prevention and in-tervention initiatives.Patients with severe HFMD displayfatal clinical manifestations with sequelae,requiring≥7days of hospitalization.A tota1 of 249 severe cases treat-ed at Yuxi Children’s Hospital were included in the case  相似文献   

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As bald eagle populations recover, defining major sources of mortality provides managers important information to develop management plans and mitigation efforts. We obtained data from necropsies on 1,490 dead bald eagles (Haliaeetus leucocephalus) collected in Michigan, USA, conducted from 1986 to 2017 to determine causes of death (COD). Trauma and poisoning were the most common primary COD categories, followed by disease. Within trauma and poisoning, vehicular trauma (n = 532) and lead poisoning (n = 176) were the leading COD subcategories, respectively. Females comprised a greater number of carcasses for most COD diagnoses. The proportion of trauma and poisoning CODs significantly increased in the last few years of the study in comparison to a select few years at the beginning. Trauma CODs were greater in autumn months during whitetail deer (Odocoileus virginianus) breeding and hunting seasons and in February, when aquatic foraging is unavailable and eagles are likely forced to scavenge along roadsides. Poisoning CODs were greatest in late winter and early spring months, when deer carcasses containing lead ammunition, which are preserved by the cold weather, also become a supplemental food source. The major infectious disease CODs, West Nile virus and botulism (Clostridium botulinum type E), were more prevalent during summer months. We recommend moving road-killed carcasses, especially white-tailed deer, from the main thoroughfare to the back of the right-of-way, and the transition from lead ammunition and fishing tackle to non-toxic alternatives to decrease these main anthropogenic sources of mortality for bald eagles, and other scavenger species. © 2020 The Wildlife Society.  相似文献   

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There has been little evidence of a decline in the global burden of cholera in recent years as the number of cholera cases reported to WHO continues to rise. Cholera remains a global threat to public health and a key indicator of lack of socioeconomic development. Overall socioeconomic development is the ultimate solution for control of cholera as evidenced in developed countries. However, most research has focused on cross-county comparisons so that the role of individual- or small area-level socioeconomic status (SES) in cholera dynamics has not been carefully studied. Reported cases of cholera in Matlab, Bangladesh have fluctuated greatly over time and epidemic outbreaks of cholera continue, most recently with the introduction of a new serotype into the region. The wealth of longitudinal data on the population of Matlab provides a unique opportunity to explore the impact of socioeconomic status and other demographic characteristics on the long-term temporal dynamics of cholera in the region. In this population-based study we examine which factors impact the initial number of cholera cases in a bari at the beginning of the 0139 epidemic and the factors impacting the number of cases over time. Cholera data were derived from the ICDDR,B health records and linked to socioeconomic and geographic data collected as part of the Matlab Health and Demographic Surveillance System. Longitudinal zero-inflated Poisson (ZIP) multilevel regression models are used to examine the impact of environmental and socio-demographic factors on cholera counts across baris. Results indicate that baris with a high socioeconomic status had lower initial rates of cholera at the beginning of the 0139 epidemic (γ01 = −0.147, p = 0.041) and a higher probability of reporting no cholera cases (α01 = 0.156, p = 0.061). Populations in baris characterized by low SES are more likely to experience higher cholera morbidity at the beginning of an epidemic than populations in high SES baris.  相似文献   

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The Tamm–Horsfall glycoprotein prepared by salt precipitation from urine was found to comprise a heterogeneous collection of aggregates. These could be disaggregated with 8m-urea, following which chromatography on a column of Bio-Gel A.15m yielded a homogeneous glycoprotein of mol.wt. 73000 together with several unidentified impurities. Gel filtration of normal plasma showed the glycoprotein to exist predominantly in a form that is eluted identically with the purified preparation. In one case, material of higher molecular weight was also detected. The purified glycoprotein was used to develop a rapid specific radioimmunoassay for its measurement in human serum or plasma by the use of the Tamm–Horsfall glycoprotein, labelled with 125I by the chloramine-t method as the tracer, an antiserum raised in rabbits, and separation of the bound and free fractions by a second antibody covalently linked to magnetizable particles. Parallelism was demonstrated between the standard preparation and samples. Recovery of added standard to serum varied between 99 and 109%. Total assay time was less than 4h with an intra-assay and inter-assay coefficient of variation of less than 10%. There were no significant differences in the ranges covered with regard to either age or sex, and no circadian rhythm was observed in normal subjects. A physiological range of 70–540ng/ml was established based on serum samples from 95 subjects with normal renal function, as defined by their serum creatinine and urea concentrations. No Tamm–Horsfall glycoprotein was detected in the serum of six anephric patients.  相似文献   

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BackgroundIn Taiwan, around 1,500 cases of dengue fever are reported annually and incidence has been increasing over time. A national web-based Notifiable Diseases Surveillance System (NDSS) has been in operation since 1997 to monitor incidence and trends and support case and outbreak management. We present the findings of an evaluation of the NDSS to ascertain the extent to which dengue fever surveillance objectives are being achieved.MethodologyWe extracted the NDSS data on all laboratory-confirmed dengue fever cases reported during 1 January 2010 to 31 December 2012 to assess and describe key system attributes based on the Centers for Disease Control and Prevention surveillance evaluation guidelines. The system’s structure and processes were delineated and operational staff interviewed using a semi-structured questionnaire. Crude and age-adjusted incidence rates were calculated and key demographic variables were summarised to describe reporting activity. Data completeness and validity were described across several variables.Conclusions/SignificanceThe NDSS for dengue fever surveillance is a robust, well maintained and acceptable system that supports the collection of complete and valid data needed to achieve the surveillance objectives. The simplicity of the system engenders compliance leading to timely and accurate reporting. Completeness of hospitalization information could be further improved to allow assessment of severity of illness. To minimize misclassification, an algorithm to accurately classify travel cases should be established.  相似文献   

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Soybean is a leading agronomic crop and contributes to food and agricultural security with expanding production areas in diverse regions around the world. Although soybean is challenged by several diseases and pests and progress has been made in understanding and managing some of these pathogens and pests, charcoal rot, incited by the soil-borne fungal pathogen Macrophomina phaseolina, has received little attention. M. phaseolina has a broad host range and is capable of attacking and infecting several groups of plant species, including soybean. Charcoal rot symptoms on soybean appear more commonly during hot and dry weather conditions, and are associated with drought stress. In recent years, it has become more important to develop management strategies to control charcoal rot in soybean fields. Understanding the genetics of this pathogen as well as its interactions with plant hosts will help in developing effective control and management strategies. The biology of M. phaseolina, its genetics, and plant–fungal relationships are reviewed herein. In addition, a discussion of potential opportunities utilizing modern tools to enhance genetic resistance against charcoal rot is also presented.  相似文献   

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Although targeted mutagenesis of Streptococcus pneumoniae is readily accomplished with the aid of natural genetic transformation and chimeric donor DNA constructs assembled in vitro, the drug resistance markers often employed for selection of recombinant products can themselves be undesirable by-products of the genetic manipulation. A new cassette carrying the erythromycin-resistance marker ermAM that can be used as a temporary marker for selection of desired recombinants is described. The cassette may subsequently be removed at will by virtue of an embedded fucose-regulated Cre recombinase gene and terminal lox66 and lox71 Cre recognition sites, with retention of 34 bp from the cassette as an inert residual double-mutant lox72 site.  相似文献   

14.
Identification of marker?Ctrait associations in germplasm relevant to a breeding program can be an effective way to identify quantitative trait loci (QTL) useful for selection and is critical to the success of genome-wide selection strategies. This approach is most cost-effective if phenotypic data routinely collected by breeding programs is used, necessitating only addition of genotypic data. The objective of this work was to evaluate such an approach using unbalanced phenotypic data from durum wheat (Triticum turgidum L. var. durum) registration trials genotyped with diversity arrays technology (DArT) markers. Plant height, grain cadmium concentration and yellow colour loss during pasta manufacture were chosen as example traits because all are influenced by major genes associated with known QTL. A further evaluation was performed on semolina yellow pigment concentration, a more complexly-inherited trait, but with numerous QTL identified. In total, 870 informative DArT markers were used to detect marker?Ctrait associations. The genome coverage of markers was uneven, with low coverage of chromosomes 4B and 5A. The DArT coverage of chromosome 4B was too sparse to identify markers strongly associated with the semidwarf height locus Rht-B1 and the lipoxygenase locus Lpx-B1, both known to reside on 4B. The 20 DArT markers associated with pigment concentration localized to chromosomes 1B, 2A, 5B, 6A, 7A and 7B, linked to the trait in other studies. One DArT clone showed sequence identity to a single wheat expressed sequence tag that maps to the same deletion bin as Psy1-A1, a gene previously associated with yellow pigment concentration in durum wheat. Three markers were associated with grain cadmium and explained similar proportions of the phenotypic variance as the Xusw14 marker known to be physically linked to Cdu-B1, a major locus on 5B regulating cadmium accumulation. The sequences of these three DArT markers were 98?% identical, and were used to identify a single gene in rice that is physically linked to other rice genes that co-localize with Cdu-B1 in durum wheat. The results suggest that this historical phenotypic dataset is useful for QTL discovery and would potentially be a ??training population?? for genomic selection when a high-density, low-cost marker platform becomes available.  相似文献   

15.
Japanese encephalitis (JE) is arguably one of the most serious viral encephalitis diseases worldwide. China has a long history of high prevalence of Japanese encephalitis, with thousands of cases reported annually and incidence rates often exceeding 15/100,000. In global terms, the scale of outbreaks and high incidence of these pandemics has almost been unique, placing a heavy burden on the Chinese health authorities. However, the introduction of vaccines, developed in China, combined with an intensive vaccination program initiated during the 1970s, as well as other public health interventions, has dramatically decreased the incidence from 20.92/100,000 in 1971, to 0.12/100,000 in 2011. Moreover, in less readily accessible areas of China, changes to agricultural practices designed to reduce chances of mosquito bites as well as mosquito population densities have also been proven effective in reducing local JE incidence. This unprecedented public health achievement has saved many lives and provided valuable experience that could be directly applicable to the control of vector-borne diseases around the world. Here, we review and discuss strategies for promotion and expansion of vaccination programs to reduce the incidence of JE even further, for the benefit of health authorities throughout Asia and, potentially, worldwide.  相似文献   

16.

Background

The epidemiology of pneumococcal meningitis in the African ‘meningitis belt’ is poorly studied. In order to ensure an effective vaccination strategy and post-vaccination surveillance, we examined the serotype distribution patterns of pneumococcal meningitis in Niger over the period 2003–2011.

Methods

Cerebrospinal fluid (CSF) samples were collected from different health facilities throughout Niger in the frame of the national microbiological surveillance of meningitis. Determination of the serotype of CSF positive for pneumococci was performed using a sequential multiplex PCR method (SM-PCR) adapted with a national algorithm in which 32 different serotypes were covered and grouped into eight consecutive PCR.

Results

The SM-PCR assay could predict the Sp serotype for 779 CSF (88.7%), 98 CSF (11.3%) were not-typeable in our national-adapted algorithm. In total, 26 different serotypes were identified. Serotype 1 (n = 393) was the most prevalent and accounted for 45.3% of infections, followed by serogroups/serotypes 12F/(12A)/(44)/(46) (7.3%), 6/(6A/6B/6C/6D) (5.4%), 14 (5.2%), 5 (4.6%), 23F (4.2%), 45 (3.6%), 2 (3.1%), 18/(18A/18B/18C/18F) (2.9%) and 17 others serotypes with a prevalence of less than 2%. The proportion of serotype 1 in infants(<2 years old) represented only 4.3% of the cases affected by this serotype. In contrast, serotypes 5, 6, 14, 19A and 23F were only detected in very young children.

Conclusions

The proportion of serotype 1 in the pneumococcal meningitis cases and the theoretical vaccine coverage across all age groups advocates for the introduction of a conjugate vaccine (PCV10 or 13) into the Expanded Programme on Immunization (EPI) in Niger. Post-vaccine introduction surveillance supported by molecular approaches will be essential to provide a comprehensive picture of the impact of the vaccine on the burden reduction of pneumococcal meningitis and on pneumococcal serotype distribution.  相似文献   

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A fast and efficient multi-residue extraction–purification procedure was developed for 12 corticosteroids in biological matrices (hair, urine and meat), in order to control their illegal use as growth promoters in cattle. Detection and identification of the analytes were achieved using a previously described LC–MS–MS method based on negative electrospray ionisation and a triple quadrupole analyser. The presented procedures included acid (hair) or enzymatic (urine and meat) hydrolysis, C18 reversed-phase SPE, Na2CO3 liquid–liquid clean-up and SiOH normal-phase SPE. The detection limits of the developed methods were between 2.9 and 9.3 pg/mg (ppb) for hair samples and in the 40 – 70 pg/g (ppt) range for the urine or meat samples. The acid hydrolysis used for corticosteroid extraction in hair was optimised using an experimental design and response surface methodology. Achieved performances were linked to a physico–chemical approach based on the corticosteroids specific C17 side-chain. This original multi-residue and multi-matrices analytical methodology will be used for further metabolism studies.  相似文献   

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Insertion–deletion polymorphism at the angiotensin I-converting enzyme (ACE) gene in populations of the Volga–Ural region was examined by means of polymerase chain reaction. The populations studied belong to the Finno-Ugric (Komis, Maris, Mordovians, and Udmurts), Turkic (Chuvashes, Tatars, and Bashkirs), and Eastern-Slavic (Russians) ethnic groups. Distribution patterns of allele and genotype frequencies of this polymorphic system in the examined region were characterized. Comparison of the obtained results with the literature data on the ACE gene polymorphism in other Caucasoid and Mongoloid populations revealed some trends in the ACE genotype frequency dynamics depending on the ethnicity of the populations.  相似文献   

19.
IntroductionMauritius, a small state, is among the few African countries where cancer registration is population based and nationwide. We reported trends in cancer incidence for twenty five years as well as the mortality to incidence ratio (MIR) as main quality indicator of the Mauritius National Cancer Registry (MNCR).Materials and methodsWe calculated age standardised incidence rates (ASRs) of cancers by sex and by 5 year age group for five successive year periods from 1991 to 2015. The average annual percentage change (AAPC) were determined by sex and cancer sites. MIRs were compared for the period 2001–2004 and 2012–2015.ResultsIn males, the most common cancer sites (in terms of ASRs per 100,000) were those of the colon-rectum (17.0), prostate (16.5), trachea-bronchus-lung (13.0), stomach (8.4) and lip-oral cavity-pharynx (7.7). The AAPC were +3.9%, +4.2%, +0.5%, -0.1% and -1.3% respectively. In females, the most frequent sites were breast (53.7), colon-rectum (13.2), cervix uteri (11.2), corpus uteri (7.7) and ovary (5.7). The AAPC were +3.4%, +4.4%, -2%, +5.2% and -0.1% respectively. The most significant decrease in MIRs among males were liver (1.9 to 1.0), stomach (1.3 to 0.8) and lung (1.7 to 1.2) cancers while among females, they were pancreas (3.4 to 1.3), liver (1.8 to 1.2) and stomach (1.5 to 0.8) cancers.ConclusionThe most common cancers were those associated with 'westernisation' of lifestyle. Our figures contrast with other Sub-Saharan Africa countries where infection related cancers are most predominant. The MNCR has also improved its data quality over time.  相似文献   

20.
Fluoride (F) pollution is a serious environmental problem in some areas of China, but it has yet to be reported in a soil–water–plant system in Shihezi, Xinjiang. This study was undertaken to investigate the distribution and migration rule of F in soil, water, and plants, and to evaluate F pollution of soil. Results showed that the average concentration of total F (T-F) in the topsoil in the northwest, north, and southeast of Shihezi was higher than the national average T-F (478 mg/kg), while it was lower in southwest. The highest T-F contents of the soil profile were detected in the depth of 20 cm. The F content in groundwater in the northwest region was higher than the GB/T 14848–93 (1.0 mg/L), whereas the F contents in other water samples were within the standard. The F contents (1.75?2.81 mg/kg) in plant leaves were higher than the food limits (1.0 mg/kg). The obtained comprehensive pollution index of the soil was 1.86, which means a mild concentration of F in Shihezi. This research has reference value for the study of F pollution and comprehensive control in the northwest oasis with the typical arid and saline conditions.  相似文献   

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