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Objective

The main aim of this study was to assess whether a history of abuse, reported during pregnancy, was associated with an operative delivery. Secondly, we assessed if the association varied according to the type of abuse and if the reported abuse had been experienced as a child or an adult.

Design

The Bidens study, a cohort study in six European countries (Belgium, Iceland, Denmark, Estonia, Norway, and Sweden) recruited 6724 pregnant women attending routine antenatal care. History of abuse was assessed through questionnaire and linked to obstetric information from hospital records. The main outcome measure was operative delivery as a dichotomous variable, and categorized as an elective caesarean section (CS), or an operative vaginal birth, or an emergency CS. Non-obstetrically indicated were CSs performed on request or for psychological reasons without another medical reason. Binary and multinomial regression analysis were used to assess the associations.

Results

Among 3308 primiparous women, sexual abuse as an adult (≥18 years) increased the risk of an elective CS, Adjusted Odds Ratio 2.12 (1.28–3.49), and the likelihood for a non-obstetrically indicated CS, OR 3.74 (1.24–11.24). Women expressing current suffering from the reported adult sexual abuse had the highest risk for an elective CS, AOR 4.07 (1.46–11.3). Neither physical abuse (in adulthood or childhood <18 years), nor sexual abuse in childhood increased the risk of any operative delivery among primiparous women. Among 3416 multiparous women, neither sexual, nor emotional abuse was significantly associated with any kind of operative delivery, while physical abuse had an increased AOR for emergency CS of 1.51 (1.05–2.19).

Conclusion

Sexual abuse as an adult increases the risk of an elective CS among women with no prior birth experience, in particular for non-obstetrical reasons. Among multiparous women, a history of physical abuse increases the risk of an emergency CS.  相似文献   

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Conservation of valuable populations must be based on a thorough understanding of their genetic variation, especially for species negatively affected by human activities. We investigated the population of larch from the nature reserve in the Gorce Mountains, which was established to preserve a unique stand of Larix decidua subsp. polonica, a remnant of one of the largest native complexes of this species. The chloroplast marker ll-TaqI was used to investigate whether the gene pool of the analysed population was contaminated with the alien larch species. We used eleven nuclear DNA microsatellite markers (nSSRs) to examine this population’s genetic diversity and verify the hypothesis about historical use of the larch from the reserve as a source of reproductive material for the Tatra Mountains. The link between the reserve population and the European larch’s ancestral groups was also verified. No contamination of the studied pool of individuals by alien species was found. The study showed high genetic variability in larch from the Gorce Mountains (HE = 0.689, HO = 0.671). The differentiation between the Gorce and Tatra National Park populations was FST = 0.038 (p < 0.001). Trees from the reserve and the national park formed two distinct genetic groups. We rejected the hypothesis that the nature reserve was the source of the regeneration material used in the Tatra Mountains. The study proved the uniqueness of the reserve population, and confirmed the appropriateness of the protection measures taken.  相似文献   

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The need to understand natural climate variability and improve weather forecasts gave birth to the first tree-ring reconstructions more than a century ago in Europe and North America, and still defines a central motivation for modern paleoclimatology: learning from the past to prepare for the future.  相似文献   

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《Dendrochronologia》2014,32(1):90-96
In the present study, 208 furniture and 168 coopered vessels from three Austrian museums were examined. Dendrochronology was used to date objects and to extract further information such as the necessary time for seasoning, wood loss through wood-working and methods of construction. In most cases sampling was done by sanding the cross section and making digital photographs using a picture frame and measuring digitally.The dendrochronological dates of the sampled furniture range between 1524 and 1937. The group of furniture includes cupboards, chests, tables, benches, commodes and beds. In many cases furniture was artfully painted and sometimes even shows a painted year. With the help of dendrochronology it was proved that some objects had been painted for some time after construction, or had been over-painted. Most furniture, however, was painted immediately after completion. In this case, the seasoning and storage time of the boards and the wood loss due to shaping can be verified. As an average value, 14 years have passed between the dendrochronological date of the outermost ring and the painting. The time span includes time of seasoning and storage and the rings lost by wood-working. This leads, on the one hand to a short storage time of less than 10 years and on the other hand to very little wood loss due to manufacturing. Those boards being less shaped turned out to be back panels of cupboards, therefore they are recommended to be sampled for dating.Coopered vessels were dated between 1612 and 1940. There was evidence that staves were split and not sawn in many cases. The staves were often split out of the outermost part of the tree and hardly any wood was worked away which was proved by the close dendrochronological dates of the single staves of a vessel.Since there is a short time of storage and only little wood loss through wood-working, dating of objects without a waney edge becomes reasonable.  相似文献   

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The archaeological site of Sovjan is situated on the edge of the Korçë Basin, southeastern Albania. Its remarkably long and well investigated stratigraphic sequence, spanning from the Neolithic till the Iron Age, makes it an important type- and reference-site for the whole region. At different periods of prehistory it was located on the shores of the former Lake Maliq that once filled the Korçë Basin, but was definitely drained in the 1940′s. These permanent wetland conditions on the site allowed for a high degree of preservation of organic material, especially wood. Based on the current knowledge, level 8 of Sovjan contains the best-preserved wooden material of all the Early Bronze Age sites in the Balkans. Through the combination of dendrochronology and Bayesian modelling, i.e. wiggle-matching, a floating 269-years long tree-ring chronology was constructed, with an absolute end-date range falling between 2158 and 2142 cal BC (2σ). It was possible to establish that the dwellings and the trackway associated with the last occupation phase of level 8 are contemporaneous. Additionally, with the help of the new dendrochronological data and based on previously published charcoal dates, the absolute chronology of the subsequent level 7 is being narrowed-down to a range from the mid-22nd to mid-20th c. cal BC (2σ). The Early Bronze Age layers of the archaeological site of Sovjan, which are particularly pertinent for the 3rd millennium chronology of the southwestern Balkans, can now be dated with high precision for the first time and hence offer a major chronological reference point in the region.  相似文献   

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《Biomass》1983,3(1):1-42
In many parts of the world, alternative energy sources are already needed or will be needed to augment fossil fuel supplies. ‘Biogas’, methanol, ethanol and hydrogen are all potentially useful in this respect, as they can be obtained (biologically or thermochemically) from renewable resources like biomass (trees, crops, etc.) and organic wastes (sewage, domestic refuse, animal manure). Some aspects of biofuel research and development in Member States of the European Community are highlighted, and estimates of the contributions that these fuels might make to current and future energy demands are reviewed. Some of the potential uses of biogases and liquid biofuels in a gas industry context are described. In the author's opinion, production of biogases and other biofuels will ultimately play a significant but relatively small rôle in conserving supplies of natural gas and other fossil fuels, and in alleviating or preventing environmental pollution.  相似文献   

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Cephalopods are highly sensitive to environmental conditions and changes at a range of spatial and temporal scales. Relationships documented between cephalopod stock dynamics and environmental conditions are of two main types: those concerning the geographic distribution of abundance, for which the mechanism is often unknown, and those relating to biological processes such as egg survival, growth, recruitment and migration, where mechanisms are sometimes known and in a very few cases demonstrated by experimental evidence. Cephalopods seem to respond to environmental variation both ‘actively’ (e.g. migrating to areas with more favoured environmental conditions for feeding or spawning) and ‘passively’ (growth and survival vary according to conditions experienced, passive migration with prevailing currents). Environmental effects on early life stages can affect life history characteristics (growth and maturation rates) as well as distribution and abundance. Both large-scale atmospheric and oceanic processes and local environmental variation appear to play important roles in species–environment interactions. While oceanographic conditions are of particular significance for mobile pelagic species such as the ommastrephid squids, the less widely ranging demersal and benthic species may be more dependent on other physical habitat characteristics (e.g. substrate and bathymetry). Coastal species may be impacted by variations in water quality and salinity (related to rainfall and river flow). Gaps in current knowledge and future research priorities are discussed. Key research goals include linking distribution and abundance to environmental effects on biological processes, and using such knowledge to provide environmental indicators and to underpin fishery management.  相似文献   

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Introduced Rana ridibunda currentlyreplace the native waterfrogs R. lessonaeand R. esculenta in several areas ofcentral Europe. The unusual reproductive systemin waterfrogs of the Rana esculentacomplex suggests that this replacement may bedriven by a genetic mechanism: Ranaesculenta, a hybrid between R. ridibundaand R. lessonae, eliminates the lessonae genome from the germline and clonallytransmits the ridibunda genome(hybridogenesis). Hybrids form mixedpopulations with R. lessonae (L-E-system)in which they persist by backcrossing with theparental species. Matings between hybrids areunsuccessful, because their ridibundagenomes contain fixed recessive deleteriousmutations. When introduced into a L-E-system,R. ridibunda can mate with both nativetaxa, producing R. ridibunda offspringwith R. esculenta, and R. esculentaoffspring with R. lessonae (primaryhybridizations). If primary hybrids arehybridogenetic, they produce viable R.ridibunda offspring in matings with otherhybrids, because their clonal genomes areunlikely to share the deleterious allelespresent in the ancient clones. Thus, R.ridibunda will increase in the population atthe expense of both native taxa, eventuallyleaving a pure R. ridibunda population.We provide three lines of evidence for thisprocess from a currently invaded population inSwitzerland: (1) Primary hybridizations takeplace, as roughly 10% of hybrids in thepopulation possess ridibunda genomesderived from the introduced frogs. (2)Hybridogenesis occurs in primary hybrids,although at a low frequency. (3) Many hybrid ×hybrid matings in the population indeed produceviable offspring. Hence, the proposed geneticmechanism appears to contribute to the speciesreplacement, although its importance may belimited.  相似文献   

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Microbial degradation of tannins – A current perspective   总被引:26,自引:0,他引:26  
Tannins are water-soluble polyphenolic compounds having wide prevalence in plants. Hydrolysable and condensed tannins are the two major classes of tannins. These compounds have a range of effects on various organisms – from toxic effects on animals to growth inhibition of microorganisms. Some microbes are, however, resistant to tannins, and have developed various mechanisms and pathways for tannin degradation in their natural milieu. The microbial degradation of condensed tannins is, however, less than hydrolysable tannins in both aerobic and anaerobic environments. A number of microbes have also been isolated from the gastrointestinal tract of animals, which have the ability to break tannin-protein complexes and degrade tannins, especially hydrolysable tannins. Tannase, a key enzyme in the degradation of hydrolysable tannins, is present in a diverse group of microorganisms, including rumen bacteria. This enzyme is being increasingly used in a number of processes. Presently, there is a need for increased understanding of the biodegradation of condensed tannins, particularly in ruminants.  相似文献   

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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   

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Introduction

In orbital reconstruction, the optimal location of a predefined implant can be planned preoperatively. Surgical results can be assessed intraoperatively or postoperatively. A novel method for quantifying orbital implant position is introduced. The method measures predictability of implant placement: transformation parameters between planned and resulting implant position are quantified.

Methods

The method was tested on 3 human specimen heads. Computed Tomography scans were acquired at baseline with intact orbits (t0), after creation of the defect (t1) and postoperatively after reconstruction of the defect using a preformed implant (t2). Prior to reconstruction, the optimal implant position was planned on the t0 and t1 scans. Postoperatively, the planned and realized implant position were compared. The t0 and t2 scans were fused using iPlan software and the resulting implant was segmented in the fused t2 scan. An implant reference frame was created (Orbital Implant Positioning Frame); the planned implant was transformed to the reference position using an Iterative Closest Point approach. The segmentation of the resulting implant was also registered on the reference position, yielding rotational (pitch, yaw, roll) as well as translational parameters of implant position.

Results

Measurement with the Orbital Implant Positioning Frame proved feasible on all three specimen. The positional outcome provided more thorough and accurate insight in resulting implant position than could be gathered from distance measurements alone. Observer-related errors were abolished from the process, since the method is largely automatic.

Conclusion

A novel method of quantifying surgical outcome in orbital reconstructive surgery was presented. The presented Orbital Implant Positioning Frame assessed all parameters involved in implant displacement. The method proved to be viable on three human specimen heads. Clinically, the method could provide direct feedback intraoperatively and could improve postoperative evaluation of orbital reconstructive surgery.  相似文献   

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ObjectiveMeningioma of the cranio-cervical junction is a rare diagnosis and demand a thorough surgical planning as radical excision of these tumors is difficult. In this context recurrence is most likely due to regrowth of residual tumor. The aim of this study was to evaluate the clinical course of patients operated for craniocervical meningioma (CCM) and to investigate the histological features of these tumors and their impact on recurrence rate.MethodsAll patients who were operated for CCM at our institution between 2003 and 2012 were identified. Presenting symptoms, MRI findings, surgical approaches and recurrence rate were reviewed retrospectively using medical charts. Histological features of the included tumors were studied focusing on subtypes and MIB-1 immunoreactivity and compared with MIB-1 immunoreactivity in an age and gender-matched control group of patients with supratentorial meningioma.Results18 patients with CCM with a mean age of 56.2 years and median follow-up of 60 months were included in the study. Sensory or motor deficit was the most frequent presenting symptom followed by neck pain and lower cranial nerve palsy. Simpson grade II resection was achieved in 16 patients and Simpson grade III resection in two patients. Mortality, morbidity and recurrence rates were 16.7%, 5.5% and 5.5%, respectively. According to the WHO-grading all were found to be grade I meningiomas. Histological subtypes included meningotheliomatous (10), transitional (2), fibrillar (2), angiomatous (3) and secretory (1) meningioma. The mean MIB-1 labeling index in the study group was significantly higher than in the control group, (7.2% and 3.6%, respectively), p < 0.05. There was no correlation between MIB-1 levels and tumor recurrence.ConclusionsCCM seems to have a benign character. Despite a significantly higher MIB-1 index, a high rate of recurrence was not observed. Therefore, approaches with high morbidity are not justified. Nevertheless, in view of the challenging approaches with limited access to the lesion, CCM should be considered a distinctive clinical subgroup.  相似文献   

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Water pollution control is presently one of the major thrust areas of scientific research. While coloured organic compounds generally impart only a minor fraction of the organic load to wastewaters, their colour renders them aesthetically unacceptable. Stringent regulating measures are coaxing industries to treat their waste effluents to increasingly high standards. Colour removal, in particular, has recently become an area of major scientific interest as indicated by the multitude of related research reports. During the past two decades, several decolourization techniques have been reported, few of which have been accepted by some industries. There is a need to find alternative treatments that are effective in removing dyes and colourants from large volume of effluents, which are cost-effective, like the biological or integrated systems. This article reviews some of the widely used and most promising industrial wastewater decolourization methods. Data on decolourizing efficiencies of different causative agents, obtained by means of different physical, chemical and biological methods are discussed. Further a critical review is made on the various treatment methodologies and emerging technologies with a note on their advantages and disadvantages.  相似文献   

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PurposeHardly anything is known about the aetiology of thymoma. This paper presents data regarding tobacco smoking and alcohol consumption in relation to thymoma from the first case-control study performed on this rare tumour.MethodsA European multi-centre case-control study including incident cases aged 35–69 years with thymoma between 1995 and 1997, was conducted in seven countries. A set of controls, used in seven parallel case-control studies by the same research group was used, including population-based controls from five countries and hospital controls with colon cancer from two countries. Altogether 103 cases, accepted by a reference pathologist, 712 colon cancer controls, and 2071 population controls were interviewed.ResultsTobacco smoking was moderately related with thymoma (OR 1.4, 95% CI 0.9–2.2), and a tendency to dose-response was shown (p = 0.04), with an increased risk for heavy smokers defined as ≥41 pack-years (OR 2.1, 95% CI 1.1–3.9). A high consumption of spirits defined as ≥25 g of alcohol per day was associated with an increased risk of thymoma (OR 2.4, 95% CI 1.1–5.4), whereas no association was found with beer or wine.ConclusionsTobacco smoking and a high intake of spirits were indicated as risk factors for thymoma.  相似文献   

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A series of ureido and bis-ureido derivatives were prepared by reacting histamine with alkyl/aryl-isocyanates or di-isocyanates. The obtained derivatives were assayed as activators of the enzyme carbonic anhydrase (CA, EC 4.2.1.1), due to the fact that histamine itself has this biological activity. Although inhibition of CAs has pharmacological applications in the field of antiglaucoma, anticonvulsant, anticancer, and anti-infective agents, activation of these enzymes is not yet properly exploited pharmacologically for cognitive enhancement or Alzheimer’s disease treatment, conditions in which a diminished CA activity was reported. The ureido/bis-ureido histamine derivatives investigated here showed activating effects only against the cytosolic human (h) isoform hCA I, having no effect on the widespread, physiologically dominant isoform hCA II. This is the first report in which CA I-selective activators were identified. Such compounds may constitute interesting tools for better understanding the physiological/pharmacological effects connected to activation of this widespread CA isoform, whose physiological function is not fully understood.  相似文献   

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Another animal to human transmission of a coronavirus occurred in December 2019 on a live animal market in the Chinese city of Wuhan causing an epidemic in China, reaching now different continents. This minireview summarizes the research literature on the virological, clinical and epidemiological aspects of this epidemic published until end of February 2020.  相似文献   

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Cultivation of microalgae requires consideration of shear stress, which is generated by operations such as mixing, circulation, aeration and pumping that are designed to facilitate mass and heat transfer as well as light distribution in cultures. Excessive shear stress can cause increased cell mortality, decreased growth rate and cell viability, or even cell lysis. This review examines the sources of shear stress in different cultivation systems, shear stress tolerance of different microalgal species and the physiological factors and environmental conditions that may affect shear sensitivity, and potential approaches to mitigate the detrimental effects of shear stress. In general, green algae have the greatest tolerance to shear stress, followed by cyanobacteria, haptophytes, red algae, and diatoms, with dinoflagellates comprising the most shear-sensitive species. The shear-sensitivity of microalgae is determined primarily by cell wall strength, cell morphology and the presence of flagella. Turbulence, eddy size, and viscosity are the most prominent parameters affecting shear stress to microalgal cells during cultivation.  相似文献   

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