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1.
Abstract

Geneticists have been able to demonstrate differences in the estimation of degrees of relationship in families as determined by genetic theory and by civil law computations which are based on the ancient concept of “blood lines.” Unfortunately, no systematic effort to clarify and resolve these discrepancies has yet been made. This work suggests a method for estimating the genetic relationship of individuals according to a given genetic family diagram and describes the differences between this system and that of civil law in most countries.  相似文献   

2.
Summary

Unfortunately the Atlantic oakwoods of Scotland have never been targeted by mycologists and information is very patchy. The best data lie in the lists of fungi from the Inner Hebridean oakwoods and it is on these records which go back to the end of the 19th century, and limited information from the mainland that a potential picture is offered. There appear to be no fungi specific to Western oakwoods and there are few differences between eastern and western oak communities in Scotland. Emphasis is placed on the need for more funding for those who can identify and recognise potential indicator species so that progress can be made.  相似文献   

3.
Abstract

Annual predictions of global deaths from civil war to the year 2001 have been made based on an earlier two‐stage cyclical model. In stage one three cycles (8.6, 17.4, and 34 yr) predict to changes in the global political system, while four cycles (5.6, 9.4, 20.5, and 54 yr) predict to changes in the global economic system. In stage two, changes in the political and economic systems predict to changes in the level of civil violence. Fifteen regression equations, four tables, and six diagrams are included with the text  相似文献   

4.
Ha  Kyong  Jang  Min-Ho  Joo  Gea-Jae 《Hydrobiologia》2003,491(1-3):221-239
Planktonic organisms exhibit diverse morphological, behavioural and life-history responses to the chemical presence of potential predators. Prey organisms have been found to sense such predators via predator-derived kairomones. The induced reactions are assumed to reduce predation risk and thus to be adaptive. Numerous studies have investigated various aspects of inducible defences in different crustaceans, in rotifers, planktonic ciliates and algae. As a first step, we summarise recent work on chemically induced anti-predator defences in morphology, life history and behaviour. Morphological defences have been found in a wide range of different plankton organisms and recent studies on predator-induced morphologies mainly addressed the question of costs for these changes. Life-history responses were mainly studied in cladocerans and several studies have recently addressed some novel topics, such as diapause induction and the influence of predator kairomones on hatching of resting stages. Behavioural anti-predator defences also have been found for several plankton species and are characterised by relatively fast induction times. We further identified four research directions in which substantial progress has been made recently: (I) The effects of simultaneous exposure to infochemicals from different predators and the consequences of a complex chemical environment. Some environmental contaminants, such as synthetic chemicals or heavy metals, have been found to potentially disturb natural chemical communication in aquatic predator-prey systems. (II) The influence of genetic variation on the reaction to infochemicals and its implications. Clonal differences have not only been found for the presence or absence of a certain trait but also with respect to the type of response. (III) The degree to which different types of responses to a specific kairomone are coupled. Recent studies underline the uncoupling of different anti-predator responses of which some have been considered to be coupled. (IV) Studies on the chemical properties and on the metabolic origin of predator kairomones. Substantial progress has been made recently, especially with respect to the identification of predator kairomones that are important for planktonic ciliates. The identification and isolation of kairomones are an important step towards studies addressing the consequences of predator-induced defences on the level of populations, communities and ecosystems. So far most studies have considered effects and consequences on the level of individual prey organisms and studies taking the consequences at higher ecological levels into account are rare.  相似文献   

5.
Summary

Thirty-four different taxa of larger fungi have been analysed for their content of caesium 137 over a 3 year period. The majority of the material has been collected from various sites in Central Scotland; 38% of the collections were from North Wales and Merseyside. Comparison has been made between the same species from different sites and different species from the same site. It has also been possible to analyse the same species from the same plot on two consecutive years. The levels of caesium 137 in the fungal species analysed were extremely low when compared with their counterparts in Central Europe and it is concluded that the Chernobyl incident had little effect on the accumulation by these fungi of this radionuclide. There is no evidence that edible species accumulate caesium 137 at levels considered to be dangerous for consumption.  相似文献   

6.
《Plains anthropologist》2013,58(64):146-148
Abstract

In an attempt to provide objective measures of the changes induced in chert by heat treatment, ten pairs of preforms were made, and one of each pair was heat treated, using a probable aboriginal technique. Paired bifaces were then chipped from the preforms. Differences in the flaking qualities of the heated and the unheated materials were noted. The bifaces made with the heat treated material were significantly thinner in cross-section than those made from raw material. Analysis of the debitage indicates that heat treatment fosters the removal of larger flakes.  相似文献   

7.
Chemical synthesis of two trisaccharides related to the triterpenoid saponins isolated from Solanum lycocarpum from commercially available d-Glc, d-Gal and l-Rha have been achieved by following concise and high-yielding route. The target trisaccharide 1 has been made by following a bis-glycosylation approach that has minimized the protecting group manipulations up to great extent. The trisaccharides have been synthesized in the form of their p-methoxyphenyl (OMP) glycosides to leave the scope for further glycoconjugates formation by the selective removal of the OMP glycoside and trichloroacetimidate chemistry. La(OTf)3 has been used successfully as the promoter for the NIS mediated activation of thioglycosides.  相似文献   

8.
Abstract

Corynebacterium glutamicum and its close relatives, C. flavum and C. lactofennentum, have been used for over 3 decades in the industrial production of amino acids by fermentation. Since 1984, several research groups have started programs to develop metabolic engineering principles for amino acid-producing Corynebacferium strains. Initially, the programs concentrated on the isolation of genes encoding (deregulated) biosynthetic enzymes and the development of general molecular biology tools such as cloning vectors and DNA transfer methods. With most of the genes and tools now available, recombinant DNA technology can be applied in strain improvement. To accomplish these improvements, it is critical and advantageous to understand the mechanisms of gene expression and regulation as well as the biochemistry and physiology of the species being engineered. This review explores the advances made in the understanding and application of amino acid-producing bacteria in the early 1990s.  相似文献   

9.
10.
《Plains anthropologist》2013,58(55):68-70
Abstract

The Cree of the Rocky Boy Indian Reservation, Montana, made a religious effigy called Män-to Kän to represent a supernatural spirit power to which gifts were made together with prayers. This secured some desired objective such as a cure for illness, to prevent illness or almost any other urgently desired end, or as an expression of gratitude for something perceived to have been granted by the supernatural.  相似文献   

11.
Abstract

According to advances in phytogeographic knowledge, a revision of boundaries for the Italian Ecoregions have been made. Main changes relate to the southern and eastern limits between Temperate and Mediterranean Divisions. The revision triggered a comprehensive update of Ecoregions for an improved support to biodiversity and sustainable management initiatives.  相似文献   

12.
ObjectivesTo compare the extent to which late 20th century patterns of mortality in London are predicted by contemporary patterns of poverty and by late 19th century patterns of poverty. To test the hypothesis that the pattern of mortality from causes known to be related to deprivation in early life can be better predicted by the distribution of poverty in the late 19th century than by that in the late 20th century.DesignData from Charles Booth''s survey of inner London in 1896 were digitised and matched to contemporary local government wards. Ward level indices of relative poverty were derived from Booth''s survey and the 1991 UK census of population. All deaths which took place within the surveyed area between 1991 and 1995 were identified and assigned to contemporary local government wards. Standardised mortality ratios for various causes of death were calculated for each ward for all ages, under age 65, and over age 65. Simple correlation and partial correlation analysis were used to estimate the contribution of the indices of poverty from 1896 and 1991 in predicting ward level mortality ratios in the early 1990s.SettingInner London.ResultsFor many causes of death in London, measures of deprivation made around 1896 and 1991 both contributed strongly to predicting the current spatial distribution. Contemporary mortality from diseases which are known to be related to deprivation in early life (stomach cancer, stroke, lung cancer) is predicted more strongly by the distribution of poverty in 1896 than that in 1991. In addition, all cause mortality among people aged over 65 was slightly more strongly related to the geography of poverty in the late 19th century than to its contemporary distribution.ConclusionsContemporary patterns of some diseases have their roots in the past. The fundamental relation between spatial patterns of social deprivation and spatial patterns of mortality is so robust that a century of change in inner London has failed to disrupt it.  相似文献   

13.
Summary

An account is given of the 5 lichens, 76 bryophytes, 40 angiosperms and the ‘sewage-fungus’ community recorded from a survey of the River Tweed, Scotland, together with historical and environmental data. For most of its length the river water is relatively soft and low in key nutrients, although phosphate levels in the past were probably higher due to the effluents from wool mills. The presence or absence of each macrophyte was recorded for successive 0.5 km lengths of the river, and histograms are included which summarise the distribution of individual species. In addition, a subjective estimate of the relative abundance within each length was made for each species, and some of these data have been included in an ordination table. Some comparison is also made with data from the literature on rivers in North-east England.  相似文献   

14.
Summary

Several examples are discussed of plants which have been exterminated from or introduced to Scotland as a result of human activities, and an attempt is made to draw lessons from these case histories. Four rare or threatened Scottish plants, Homogyne alpina, Mertensia maritima, Primula scotica, and Pteridium aquilinum ssy. latiusculum are considered to illustrate future plant conservation imperatives. Threats to the Scottish flora of a more “institutional” nature are discussed, and it is suggested that these point to the need for botanical societies to consider a more “campaigning” role.  相似文献   

15.
ObjectivesTo discover whether post-combat syndromes have existed after modern wars and what relation they bear to each other.DesignReview of medical and military records of servicemen and cluster analysis of symptoms.ResultsThree varieties of post-combat disorder were identified—a debility syndrome (associated with the 19th and early 20th centuries), somatic syndrome (related primarily to the first world war), and a neuropsychiatric syndrome (associated with the second world war and the Gulf conflict). The era in which the war occurred was overwhelmingly the best predictor of cluster membership.ConclusionsAll modern wars have been associated with a syndrome characterised by unexplained medical symptoms. The form that these assume, the terms used to describe them, and the explanations offered by servicemen and doctors seem to be influenced by advances in medical science, changes in the nature of warfare, and underlying cultural forces.

What is already known on this topic

Service in the Gulf war is associated with an increased rate of reported symptoms and worsening subjective healthPost-combat syndromes have been described after most modern conflicts from the US civil war onwards

What this study adds

There seems to be no single post-combat syndrome but a number of variations on a themeThe ever changing form of post-combat syndromes seems to be related to advances in medical understanding, the developing nature of warfare, and cultural undercurrentsBecause reported symptoms are subject to bias and changing emphasis related to advances in medical science or the discovery of new diseases, the characterisation of individual syndromes has to be treated with cautionAttributions by servicemen are generally consistent with symptom characteristics, though there seems to be a growing reluctance to consider the stress of military service as a cause  相似文献   

16.
Abstract

Many attempts have been made to design derivatives of analog nucleotides that might circumvent resistance due to deficiency of enzymes that convert analogs of purines, pyrimidines and nucleosides to nucleotides. None of these prodrugs that have been evaluated has been active against resistant tumor cells in vivo. The probable reason for this failure is that host cells, but not the resistant cells, have the capacity to form toxic nucleotides from bases or nucleosides resulting from degradation of the prodrugs. These considerations indicate that this strategy for circumvention of resistance will be successful only if the prodrug has some property, other than ability to enter the cell and be converted to toxic nucleotide, that will result in selective toxicity to resistant cells.  相似文献   

17.
《Endocrine practice》2012,18(4):611-615
ObjectiveTo provide information on molecular bio markers that can help assess cytologically indeterminate thyroid nodules.MethodsPublished studies on immunohistologic, somatic mutation, gene expression classifier, microRNA, and thyrotropin receptor messenger RNA biomarkers are reviewed, and commercially available molecular test pan els are described.ResultsThyroid nodules are common, and clinical guidelines delineate an algorithmic approach including serum thyroid-stimulating hormone measurement, diagnostic ultrasound examination, and, when appropriate, fine-needle aspiration (FNA) biopsy for determination of a benign versus malignant status. In clinical practice, approximately 20% of FNA-derived cytology reports are classified as “indeterminate” or follicular nodules that do not fulfill either benign or malignant criteria. In this set ting, the actual risk for malignancy of a cytologically indeterminate nodule ranges from approximately 15% to 34%. Research describing molecular biomarkers from thyroid cancer tissue has been applied to FNA-derived thyroid nodule material. There is also a serum molecular marker that has been reported with goals similar to those for the FNA-derived molecular markers: to enhance the preoperative diagnosis of thyroid cancer and reduce the large number of patients who have a diagnostic surgical procedure for benign thyroid nodules.ConclusionProgress toward the foregoing goals has been made and continues to evolve with the recent appearance of molecular biomarker tests that can be selectively applied for further assessment of cytologically indeterminate thyroid nodules. (Endocr Pract. 2012;18:611-615)  相似文献   

18.

The kiore, once common throughout New Zealand, had disappeared from most of the country by the end of the 19th century, and is now found only on certain offshore islands and in areas of Fiordland where at least one of the three introduced European rodent species is absent. It is usually accepted that the kiore was displaced by ship rats (Rattus r. rattus) and Norway rats (R. norvegicus). However, recent investigations on Stewart Island have revealed kiore, ship rats, and Norway rats living in close association, but in the absence of mice (Mus musculus). In the area studied the kiore seemed to inhabit mainly grassland. Re‐examination of possible reasons for the decline of the kiore strongly suggests that competition from mice has been a major contributing factor. It seems that in New Zealand a niche no longer exists for kiore once mice, ship rats, and Norway rats have all become established.  相似文献   

19.
Summary

A detailed study of the desmid flora of the area covered by the parish of Assynt, West Sutherland, has been made. Some 79 samples have been examined necessitating more than 1200 separate determinations of 291 taxa present. Amongst the desmids identified there are some extremely rare species and others newly recorded for the British Isles. The survey has shown that this sector of Sutherland is a prime area of the United Kingdom for the study of these fascinating and beautiful micro-algae.  相似文献   

20.
ABSTRACT

A new rule stipulates that wine made in Japan from grapes harvested in Japan be labeled as “Japan wine”. The main grape varieties for Japan Wine, Koshu for white wine and Muscat Bailey A for red, are unique to Japan. Koshu is native to Japan and its origin, long unknown, has recently been revealed through DNA analysis. Wine made from this variety suffered from a lack of characteristic aroma, but a recent study has demonstrated its potential for producing wine with a citrus scent. Muscat Bailey A was bred in Japan. Its characteristic sweet aroma has been identified as being due to furaneol. Another characteristic of its wine is that it has a low concentration of proanthocyanidins (condensed tannin), and the reason for this was revealed recently. These and other studies have been conducted in wine companies, universities, and research institutes in Japan and support the development of Japan Wine.

Abbreviations: SSR: simple sequence repeat; SNP: single nucleotide polymorphism; 3MH: 3-mercaptohexan-1-ol; 4-HDMF: 4-hydroxy-2,5-dimethyl-3(2H)-furanone; PCA: principal component analysis  相似文献   

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