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31.
The genusGlycine has had a stormy taxonomic history. Recent studies of herbarium specimens and cytological and morphological analyses of living collections, coupled with chemotaxonomic investigations, have made it necessary to revise the genus. In the first part of this paper the current taxonomic status of the genusGlycine is reviewed. The soybean was domesticated in China. It is unfortunate that the literature concerned with the antiquity and historical development of the soybean is obscured by legends and myths. In the second section of the paper, the archeological, historical, agricultural and botanical literature is summarized in order to present all the known evidence as to when, where and by whom the soybean was domesticated. The soybean is the world’s premier source of dietary vegetable oil and is nutritionally an excellent and inexpensive source of protein for use either as human food or animal feed. In addition, the soybean has numerous industrial uses. In the last section of this paper the traditional uses of fermented and nonfermented soybeans in the East as well as the high-technology-developed uses of soybeans in the West are summarized.  相似文献   
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Seed of the genusGlycine Willd. typically exhibits a muriculate appearance resulting from adherence to the true seed coat of the perisperm or inner pod wall layer. Thickened cell walls of the perisperm superimpose a reticulate network on the seed coat, the type of network ranging from alveolate to stellate depending on the shape of the perisperm cells. Tubercles distributed at intervals give the seed its roughened appearance. Seed lacking an attached perisperm appears smooth and shiny. Seed morphology of 62 collections representing the six species of the subgenusGlycine is examined in detail to elucidate inter-and intraspecific variability. Seed perisperm pattern appears to be characteristic for each species, but there are exceptions.Glycine canescens F. J. Herrn. andG. clandestina Willd. seeds possess a reticulate network and tubercles of irregular shape, the perisperm appearing granular inG. clandestina. Seeds ofG. latrobeana (Meissn.) Benth. andG. tabacina (Labill.) Benth. lack a distinct network and have stellate tubercles; the perisperm is granular inG. latrobeana and some plants ofG. tabacina. A few collections ofG. clandestina approachG. tabacina in seed appearance.Glycine tomentella Hayata seeds exhibit a regularly alveolate arrangement, while those ofG. falcata Benth. lack a perisperm layer altogether. Variation in seed coat within a species can usually be linked to differences in chromosome number or some aspect of gross morphology. Diploid collections ofG. tomentella (2n = 40) exhibit recognizable differences in seed morphology compared with tetraploids (2n = 80), coincident with other striking dissimilarities in gross morphology. An incompletely attached perisperm is accompanied by aneuploidy in severalG. tomentella accessions, while other 78 and 38 chromosome aneuploids produce normal seeds.  相似文献   
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Background

Gas trapping quantified on chest CT scans has been proposed as a surrogate for small airway disease in COPD. We sought to determine if measurements using paired inspiratory and expiratory CT scans may be better able to separate gas trapping due to emphysema from gas trapping due to small airway disease.

Methods

Smokers with and without COPD from the COPDGene Study underwent inspiratory and expiratory chest CT scans. Emphysema was quantified by the percent of lung with attenuation < −950HU on inspiratory CT. Four gas trapping measures were defined: (1) Exp−856, the percent of lung < −856HU on expiratory imaging; (2) E/I MLA, the ratio of expiratory to inspiratory mean lung attenuation; (3) RVC856-950, the difference between expiratory and inspiratory lung volumes with attenuation between −856 and −950 HU; and (4) Residuals from the regression of Exp−856 on percent emphysema.

Results

In 8517 subjects with complete data, Exp−856 was highly correlated with emphysema. The measures based on paired inspiratory and expiratory CT scans were less strongly correlated with emphysema. Exp−856, E/I MLA and RVC856-950 were predictive of spirometry, exercise capacity and quality of life in all subjects and in subjects without emphysema. In subjects with severe emphysema, E/I MLA and RVC856-950 showed the highest correlations with clinical variables.

Conclusions

Quantitative measures based on paired inspiratory and expiratory chest CT scans can be used as markers of small airway disease in smokers with and without COPD, but this will require that future studies acquire both inspiratory and expiratory CT scans.  相似文献   
38.

Background

The association of HIV with chronic morbidity and inflammatory markers (cytokines) in older adults (50+years) is potentially relevant for clinical care, but data from African populations is scarce.

Objective

To examine levels of chronic morbidity by HIV and ART status in older adults (50+years) and subsequent associations with selected pro-inflammatory cytokines and body mass index.

Methods

Ordinary, ordered and generalized ordered logistic regression techniques were employed to compare chronic morbidity (heart disease (angina), arthritis, stroke, hypertension, asthma and diabetes) and cytokines (Interleukins-1 and -6, C-Reactive Protein and Tumor Necrosis Factor-alpha) by HIV and ART status on a cross-sectional random sample of 422 older adults nested within a defined rural South African population based demographic surveillance.

Results

Using a composite measure of all morbidities, controlling for age, gender, BMI, smoking and wealth quintile, HIV-infected individuals on ART had 51% decreased odds (95% CI:0.26-0.92) of current morbidity compared to HIV-uninfected. In adjusted regression, compared to HIV-uninfected, the proportional odds (aPOR) of having elevated inflammation markers of IL6 (>1.56pg/mL) was nearly doubled in HIV-infected individuals on (aPOR 1.84; 95%CI: 1.05-3.21) and not on (aPOR 1.94; 95%CI: 1.11-3.41) ART. Compared to HIV-uninfected, HIV-infected individuals on ART had >twice partial proportional odds (apPOR=2.30;p=0.004) of having non-clinically significant raised hsCRP levels(>1ug/mL); ART-naïve HIV-infected individuals had >double apPOR of having hsCRP levels indicative of increased heart disease risk(>3.9ug/mL;p=0.008).

Conclusions

Although HIV status was associated with increased inflammatory markers, our results highlight reduced morbidity in those receiving ART and underscore the need of pro-actively extending these services to HIV-uninfected older adults, beyond mere provision at fixed clinics. Providing health services through regular community chronic disease screening would ensure health care reaches all older adults in need.  相似文献   
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Opportunities for associationist learning of word meaning, where a word is heard or read contemperaneously with information being available on its meaning, are considered too infrequent to account for the rate of language acquisition in children. It has been suggested that additional learning could occur in a distributional mode, where information is gleaned from the distributional statistics (word co-occurrence etc.) of natural language. Such statistics are relevant to meaning because of the Distributional Principle that ‘words of similar meaning tend to occur in similar contexts’. Computational systems, such as Latent Semantic Analysis, have substantiated the viability of distributional learning of word meaning, by showing that semantic similarities between words can be accurately estimated from analysis of the distributional statistics of a natural language corpus. We consider whether appearance similarities can also be learnt in a distributional mode. As grounds for such a mode we advance the Appearance Hypothesis that ‘words with referents of similar appearance tend to occur in similar contexts’. We assess the viability of such learning by looking at the performance of a computer system that interpolates, on the basis of distributional and appearance similarity, from words that it has been explicitly taught the appearance of, in order to identify and name objects that it has not been taught about. Our experiment tests with a set of 660 simple concrete noun words. Appearance information on words is modelled using sets of images of examples of the word. Distributional similarity is computed from a standard natural language corpus. Our computation results support the viability of distributional learning of appearance.  相似文献   
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