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1.
The "AACHEN 3D Finger" is a three-dimensional measuring system for use in all fields of dentistry. The system can equally as well be installed on a plane table, as fixed to the head of a patient. The measuring device is computer-assisted, and is able to localize, register and calculate any combination of points in the oral and maxillofacial area. The reference system can be changed at any time. The "AACHEN 3D Finger" can be used as a computer-a ded system in dentistry as well as in implantology or dental and maxillofacial surgery.  相似文献   

2.
Utilization of dermatoglyphics for population studies is apparently increasing, but methods vary widely among investigators. We investigate how different types of dermatoglyphic data can affect estimates of biological distance among Finno-Ugric speaking populations. Dermatoglyphic distances were calculated using the following categories of traits: 1) Finger ridge-counts (radial and ulnar count for each digit), 2) finger ridge-counts (largest count for each digit), 3) finger pattern types, 4) palm ridge-counts, 5) palm patterns, and 6) main-line terminations. In addition, we compare our distances with those of Heet, which rely heavily on summary characters. Distances are evaluated by comparing them to each other and to language and geographic distances. There is considerable variation in the pattern of relationships resulting from the different variable sets. Finger variables, whether ridge-counts or pattern classifications, agree well with each other. Palm patterns, main-lines, and finger variables show moderate agreement with each other, while palm ridge-counts agree poorly with all variable sets except main-lines. Heet's distances agree poorly with all other dermatoglyphic distances. Finger patterns and main-lines are most closely related to language distances, after controlling for geography, while correlations with geography generally disappear after controlling for language. Heet's distances have weak associations with language and geography. Finger variables and palm main-lines yield results which agree best with historical relationships among Finno-Ugric populations. Our results make it very clear that utilization of dermatoglyphics in population studies requires careful consideration of methods, and that summary measures of quantitative or qualitative data should be used with caution.  相似文献   

3.
Dr. W. F. H. Ströer 《Genetica》1935,17(3-4):299-312
Zusammenfassung Eine Familie mit hereditären Hand- und Fussabweichungen in fünf Generationen (vergl. Abb. 6. Taf. XIV) wurde beschrieben. An den Händen ist nur ein normaler Finger konstant vorhanden, der Zeigefinger (II). Die ulnare Fingergruppe ist charakterisiert durch das Vorhandensein eines überzähligen, metakarpallosen sechsten Fingers, welcher syndaktyl mit zwei (IV und V), oder drei (III, IV und V) ulnaren Fingern verbunden ist. Im ersten Fall sind zwei normale Finger (II und III) vorhanden. Die Glieder, die sich radialwärts vom Zeigefinger befinden, zeigen eine gewisse Variation. Im einfachsten Fall ist hier nur ein Finger mit drei Phalangen vorhanden; im extremsten zwei solcher Finger, wovon der radiale am Ende verdoppelt ist; dazwischen gibt es eine Reihe von Übergangsformen. Die Handabweichungen bestanden aus einer Polydaktylie mit einer Fingerzahl von 6 bis 8 Fingern; wobei eine partielle Syndaktylie vorlag. Eine Reihe von Übergangsformen, von welchen einige schöne Verknöcherungsstadien zeigten, wurde beschrieben.Die Fussabweichungen bestanden aus einer partiellen Syndaktylie.Ein einfacher vollkommen oder unvollkommen dominanter Mendelfaktor mit modifizerendem Einfluss der Umwelt wurde als Erklärung angenommen.Mit 3 Tafeln  相似文献   

4.
指(趾)骨异常是人群中较为常见的一种遗传缺陷,一般为常染色体显性遗传,也有少数以常染色体隐性遗传的方式传递,包括四肢大范围的缺失缺陷,也包括细微的指(趾)数目、长度、解剖形态结构的变化,是由于遗传进化过程中的变异或发育过程中的不良因素(如异常子宫内环境)所致.指(趾)骨异常可以分为多指(趾)并指(趾)症(Synpolydactyly,SPD)、手足裂畸形(split-hand/split-foot malformation,SHFM)和短指(趾)(Brachydactyly,BD).本文综述了指(趾)骨异常的分类及其遗传特点,总结了指(趾)骨异常畸形相关基因的研究进展.  相似文献   

5.
Aim Climate, topography and soils drive many patterns of plant distribution and abundance across landscapes, but current plant communities may also reflect a legacy of past disturbance such as agricultural land use. To assess the relative influences of environmental conditions and disturbance history on vegetation, it is important to understand how these forces interact. This study relates the geographical distribution of land uses to variation in topography and soils; evaluates the consequences of land‐use decisions for current forests; and examines the effects of agricultural land use on the chemical properties of forest soils. Location Tompkins County occupies 1250 km2 in central New York's Finger Lakes region. Like much of eastern North America, this area underwent forest clearance for agriculture during the 1800s and widespread field abandonment and forest recovery during the 1900s. The current landscape consists of a patchwork of forests that were never cleared, forests that developed on old fields and active agricultural lands. Methods We investigated relationships among topography, soils and land‐use decisions by gathering information about land‐use history, slope, aspect, elevation, soil lime content, soil drainage and accessibility in a geographic information system (GIS). To assess the effects of agriculture on forest soil chemistry, we measured pH, organic matter content and extractable nutrient concentrations in field‐collected soil samples from 47 post‐agricultural and uncleared forests. Results Steeper slopes, less accessible lands and lower‐lime soils tended to remain forested, and farmers were more likely to abandon fields that were steeper, farther from roads, lower in lime and more poorly drained. Slope had by far the greatest impact on patterns of clearance and abandonment, and accessibility had a surprisingly strong influence on the distribution of land uses. The effects of other factors varied more, depending for example on location within the county. Current forest types differed accordingly in topography and soil attributes, particularly slope, but they also showed much overlap. Post‐agricultural and uncleared forest soils had similar chemical properties. Forests on lands abandoned from agriculture 80–100 years before had slightly higher pH and nutrient concentrations than adjacent, uncleared forests, but these changes were small compared to environmental variation across the county. Main conclusions Despite differential use of lands according to their topography and soils, the substantial influence of accessibility and the relatively small scale of land‐use decisions allowed for broad similarity among forest types. Thus, the topography and soil differences created by land‐use decisions probably contribute little to landscape‐level patterns of diversity. Subtle changes in forest soil chemistry left from past agriculture may nevertheless affect plant distribution and abundance at finer scales.  相似文献   

6.
Efficacy and phytotoxicity of lime sulphur in organic apple production   总被引:3,自引:0,他引:3  
Curative and preventive efficacy and phytotoxicity of lime sulphur spray schedules, based on a warning system, were evaluated in the Netherlands during two growing seasons under field conditions. In most cases, lime sulphur treatments applied either curatively or preventively resulted in significantly lower scab damage on both the leaves and fruits compared to wettable sulphur treatments. However, all lime sulphur treatments showed high phytotoxicity values, reduced leaf size and had a tendency to a reduced yield quality compared to all other treatments. For curative schedules of lime sulphur on scab control, phytotoxicity and yield did not differ significantly from preventive schedules of lime sulphur. However, the use of a warning system combined with curative schedules of lime sulphur saved one and two lime sulphur sprays in 2000 and 2001, respectively, compared to the preventive treatments of lime sulphur. Our results demonstrated that a curative spray programme with lime sulphur at 0.75–2%, applied 35–45 h after predicted infection periods, can provide effective primary apple scab control, but no benefit in either yield or fruit quality was reached under organic growing conditions. Moreover, research herein clearly showed that organic growers are forced to find a balance between good efficacy and phytotoxic effects of lime sulphur.  相似文献   

7.
以“碳失汇”科学之谜和碳捕集与封存技术发展为背景,从石灰碳化原理、影响因素和石灰在化工、冶金、建筑以及石灰窑灰处理等领域的利用方式,综述了石灰物质流动过程的碳汇研究.结果发现: 石灰材料和环境条件是影响碳化的主要因素;石灰碳汇主要集中在化工、冶金和建筑领域;已有研究侧重分析石灰碳汇的机理、影响因素,但缺乏系统的碳汇核算方法.今后的研究工作应从以下几方面加强: 从物质流动的角度出发,建立系统完整的石灰碳汇核算方法;量化我国乃至全球的石灰碳汇量,阐明石灰生产过程中排放的CO2抵消比例;分析石灰碳汇对碳失汇的贡献比例,明晰部分失踪碳汇;推动石灰碳捕集与封存技术发展,为我国应对气候变化国际谈判提供科学依据.  相似文献   

8.
石灰碳汇综述   总被引:1,自引:1,他引:0  
以“碳失汇”科学之谜和碳捕集与封存技术发展为背景,从石灰碳化原理、影响因素和石灰在化工、冶金、建筑以及石灰窑灰处理等领域的利用方式,综述了石灰物质流动过程的碳汇研究.结果发现: 石灰材料和环境条件是影响碳化的主要因素;石灰碳汇主要集中在化工、冶金和建筑领域;已有研究侧重分析石灰碳汇的机理、影响因素,但缺乏系统的碳汇核算方法.今后的研究工作应从以下几方面加强: 从物质流动的角度出发,建立系统完整的石灰碳汇核算方法;量化我国乃至全球的石灰碳汇量,阐明石灰生产过程中排放的CO2抵消比例;分析石灰碳汇对碳失汇的贡献比例,明晰部分失踪碳汇;推动石灰碳捕集与封存技术发展,为我国应对气候变化国际谈判提供科学依据.  相似文献   

9.
Aphids can cause major environmental problems in urban areas. One important problem is the annual outbreaks of lime aphid, Eucallipterus tiliae (L.) (Hemiptera: Aphididae), which spoil the surroundings of lime trees by depositing honeydew. To date no environmentally friendly method has been demonstrated to yield effective control of lime aphids. Attempts are made in some cities to control lime aphids by releasing larvae of the native two-spot ladybird beetle, Adalia bipunctata (L.) (Coleoptera: Coccinellidae). However, it is known that adult ladybird beetles disperse soon after release, and there is little indication they provide control of the aphids. Here, we demonstrate experimentally that releases of a flightless strain of A. bipunctata, obtained from natural variation in wing length, can reduce the impact of honeydew from lime aphid outbreaks on two species of lime in an urban environment. Both larvae and adult beetles were released, and we discuss the contribution of the flightless adults to the decline in honeydew.  相似文献   

10.
In this paper the dermatoglyphics of an Eastern Andalusia series were analysed. The obtained data consists of 204 students (101 males and 103 females) from the University of Granada. According to their ancestors and the geographical position of this university, the sample can be considered as representtive of the Oriental Andalusia. The following traits were studied: Finger pattern types, Pattern intensity, Finger ridge-count, Main lines terminations, Axial triradius and Patterns of the five cofigurational areas of the palm. For every trait, the general values, as well as, the bimanual and sexual differences were calculated. This study, joined to a global consideration of the traits in several populations, allow us to conclude that the Andalusians are clearly placed whitin the spanish variability.  相似文献   

11.
Lignocellulosic biomass was pretreated with lime, and used for the production of VFA (volatile fatty acid) through batch anaerobic digestion. About 0.34 g VFA yield was obtained using 10 g/L reed, after 3 days of fermentation with lime treatment; however, a higher VFA yield (more than 0.5 g/g biomass) was achieved with a modified lime treatment. Overall, our study showed that that the modified lime treatment is better suited for VFA production. VFAs can be widely used in platforms for fuels and chemicals from biomass.  相似文献   

12.
We discovered a new species of the genus Gracixalus,Gracixalus tianlinensis sp.nov.which is morphologically almost similar to G.jinggangensis,G.jinxiuensis and G.sapaensis,but is distinguished from these species and all other rhacophorids in China and adjoining countries by a combination of the following characters:(1)SVL 30.3-35.9 mm in male,35.6-38.7 mm in female,(2)head length less than head width,(3)vomerine teeth absent,(4)supratympanic fold distinct,(5)axilla and posterior surface of flanks pale yellow,(6)nuptial pads distinct on Finger I and slightly visible on Finger II,(7)dorsum brown to beige,with an inverse Y-shaped dark brown marking,(8)single subgular vocal sac.Our preliminary phylogenetic analyses implied G.tianlinensis sp.nov.is sister to G.sapaensis with well-supported values.Currently,this new species is known to be distributed in montane evergreen forests in association with montane bamboo in Cenwanglaoshan National Nature Reserve,Tianlin County,Guangxi,China.  相似文献   

13.
赫哲族掌指纹特征研究   总被引:9,自引:5,他引:4  
本文对166名健康赫哲族人的掌指纹进行了研究,其中男性86名,女性80名。本文列出了58个赫哲族掌指纹参数,将其中52个掌指纹特征输入电子计算机,进行了相关及主成份分析。并且,将赫哲族的掌指纹特征与汉族的掌指纹特征进行了比较。 结果表明:赫哲族的掌指纹特征是与汉族相似的,并且有自己的特征;双手同名指的相关系数大于非同名指,单手相邻指的相关系数大于相隔指;在有关掌指纹特征的研究中,指纹的重要性大于掌纹。  相似文献   

14.
Iran has a long history of acid lime cultivation and propagation. In this study, genetic variation in 28 acid lime accessions from five regions of south of Iran, and their relatedness with other 19 citrus cultivars were analyzed using Simple Sequence Repeat (SSR) and Inter-Simple Sequence Repeat (ISSR) molecular markers. Nine primers for SSR and nine ISSR primers were used for allele scoring. In total, 49 SSR and 131 ISSR polymorphic alleles were detected. Cluster analysis of SSR and ISSR data showed that most of the acid lime accessions (19 genotypes) have hybrid origin and genetically distance with nucellar of Mexican lime (9 genotypes). As nucellar of Mexican lime are susceptible to phytoplasma, these acid lime genotypes can be used to evaluate their tolerance against biotic constricts like lime “witches’ broom disease”.  相似文献   

15.
Finger and palm prints were collected from 306 Nepalese males belonging to the Kiranti, Gurung and Mangar tribes of Nepal. The dermatoglyphic characteristics show affinities with other Asiatic Mongoloid populations especially those residing in the southern Himalayas.  相似文献   

16.
A. F. G. Dixon 《Oecologia》1973,13(3):205-210
Summary Both sycamore and lime aphids live on the leaves of their respective host trees. The sycamore aphid unlike the lime aphid has the ability to adapt metabolically to changes in temperature. The difference in ability of these two tree-dwelling aphids to adapt metabolically to changes in temperature can be related to their mode of life. The sycamore aphid lives on sycamore which is native to the mountainous areas of southern and central Europe where conditions are cool. Sycamore also has a longer growth period than lime as its buds burst earlier and it sheds its leaves later. Sycamore aphids are therefore naturally exposed to a wider range of temperatures than lime aphids.  相似文献   

17.
Finger and a-b palmar ridge-count dermatoglyphic features were studied in schizophrenics with and without a positive family history of schizophrenia. Associations are reported for low quantitative dermatoglyphic values in schizophrenia. The differences found between the two subgroups of patients support the genetic heterogeneity of schizophrenia and stress the existence of congenital factors when there is no family history, that is, a genetic background.  相似文献   

18.

1. The aim of this study was to investigate if finger temperature or finger blood flow is the critical factor for maintenance of finger dexterity during cold exposure.

2. Subjects were exposed twice to −25°C air for 3 h by using a Torso Heating Test (THT) where the torso was maintained to 42°C with a heating vest while the hands were bare, and a Hand Heating Test (HHT) where the hands were heated with heated gloves.

3. Despite similar finger temperatures, finger blood flow was eight times lower and finger dexterity was decreased in HHT as compared to THT.

4. It is concluded that finger blood flow is the critical factor to maintain finger dexterity in the cold.

Author Keywords: Finger dexterity; Finger temperature; Auxiliary heating; Cold exposure; Heating gloves; Torso heating; Comfort of extremities  相似文献   


19.
1. The main focus of this study was to investigate the effects of single and multiple moderate doses of lime (slaked lime, Ca(OH)2, and/or calcite, CaCO3) on eutrophic hardwater lakes. This information would contribute to strategies to manage phytoplankton and macrophyte biomass in eutrophic lakes.
2. Water chemistry and biota were monitored for up to 7 years after initial lime treatment and results were compared with reference systems.
3. Complementary studies investigated the effect of lime on macrophytes in ponds, irrigation canals and microcosm experiments.
4. When water pH was kept within its natural range (≤ 10), single and multiple lime applications to lakes and ponds controlled macrophyte biomass, without negatively affecting invertebrate communities.
5. Single lime treatments at moderate dosages of lakes and ponds resulted in variable and mostly temporary changes in chlorophyll a (chl a ) and phosphorus (P) concentration. Although sediment P release was reduced in single-dose lakes during the first winter following treatment, reductions appeared temporary.
6. Multiple treatments of lakes and ponds were effective at reducing both chl a and P concentrations over longer periods. Mean winter P release rate was also reduced after initial treatment.
7. In laboratory studies, sediment cores were incubated with eight different treatments to assess P release. Redox-sensitive treatments were no more effective at lowering total P concentration in overlying water than some redox-insensitive treatments. Lime reduced total P concentrations, but was not as effective as treatments with alum.
8. The use of lime in managing macrophyte and phytoplankton biomass in shallow, hardwater lakes and ponds may be preferable over other treatments, because lime is economical and non-toxic as long as pH is kept within a natural range.  相似文献   

20.
Finger clubbing, measured objectively by using the hyponychial angle, was present in 75 out of 200 (38%) patients with Crohn''s disease, 15 out of 103 (15%) with ulcerative colitis, and two out of 24 (8%) with proctitis. In Crohn''s disease and ulcerative colitis the hyponychial angle was significantly correlated with both disease activity and the extent of fibrosis in the resected specimens from 47 surgically treated patients. The prevalence of finger clubbing in patients with macroscopic disease within the area of the gut innervated by the vagus nerve was significantly higher than that in patients in whom the disease was confined to the distal colon and rectum. Finger clubbing in patients with Crohn''s disease tended to regress after resection of macroscopic disease. It is concluded that finger clubbing is significantly commoner in Crohn''s disease than ulcerative colitis. The focal stimuli for finger clubbing include mucosal inflammatory change and fibrosis mediated by the vagus and possibly other autonomic pathways acting as the afferent arc of a finger-clubbing reflex.  相似文献   

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