首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 9 毫秒
1.
2.
3.
4.
5.
A new technique to correct facial paralysis.   总被引:6,自引:0,他引:6  
In two cases of unilateral ficial paralysis, the advanced atrophy of the muscles forced us to try a new technique for dynamin reanimation. To our knowledge, this has not yet been reported in the literaturel. The technique combines a free nerve graft across the face with a free muscle graft or a muscle flap. The result in both our cases was good.  相似文献   

6.
7.
8.
Thulborn, T. 190: Dinosaur Tracks.
Gillette, D. D. & Lockley, M. G. (eds.) 1989: Dinosaur Tracks and Trores  相似文献   

9.
10.
11.
12.
13.
14.
Method agreement analysis: A review of correct methodology   总被引:2,自引:0,他引:2  
P.F. Watson  A. Petrie 《Theriogenology》2010,73(9):1167-1179
The correct approach to analyzing method agreement is discussed. Whether we are considering agreement between two measurements on the same samples (repeatability) or two individuals using identical methodology on identical samples (reproducibility) or comparing two methods, appropriate procedures are described, and worked examples are shown. The correct approaches for both categorical and numerical variables are explained. More complex analyses involving a comparison of more than two pairs of data are mentioned and guidance for these analyses given. Simple formulae for calculating the approximate sample size needed for agreement analysis are also given. Examples of good practice from the reproduction literature are cited, and common errors of methodology are indicated.  相似文献   

15.
16.
Inverted nipples are cosmetically unpleasing to the patient and can become inflamed due to mechanical difficulty with cleaning the nipple-areola complex. A surgical technique for the permanent repair of inverted nipples is described. The rationale for the surgical approach is that the major pathophysiologic basis for nipple inversion is shortened lactiferous ducts. Briefly outlined, under local anesthesia, the nipple is everted with a skin hook and held in gentle traction while a small incision is made on each side at the nipple-areola junction. Breast ducts are then divided by sharp dissection, and a drain is inserted through the tunnel under the nipple. The drain is removed in 7 to 10 days. The patient must be informed before the procedure that breast-feeding will not be possible afterward because breast ducts will be permanently divided. Advantages to the procedure are (1) no scars on the areola, (2) no stricture from sutures, (3) adequate blood and nerve supply to the nipple, and (4) decreased risk of hematoma.  相似文献   

17.
The chemosystematics ofRutaceae is reviewed on the basis of updated surveys of various secondary metabolites and their biosynthetic derivation. A comparison of these data with the morphological and geographical differentiation clearly shows that the current taxonomic arrangement of the family is to a large extent artificial and needs improvement. Starting from obviously natural groups of genera (or single genera) as basic taxonomic entities a new system with informal tribal names is suggested. In particular, the subfamilyToddalioideae is broken up altogether and its former members are rearranged among several of the 17 provisional tribes within the subfamilyRutoideae s. lat. Phylogenetic progressions can be recognized from parallel changes of morphological characters and biosynthetic pathways to secondary metabolites. As a general trend, a stepwise replacement of benzylisoquinolines by simple and complex anthranilic acid derived alkaloids, and eventually by coumarins and/or limonoids is confirmed. The available data are summarized in a discussion of the possible evolutionary relationships among theRutaceae, with theZanthoxylum- andEvodia-tribes in a central position.  相似文献   

18.
By assigning time-varying coordinates to all environmental stimuli, it has been possible to axiomatize psychoanalytic theory on the five principles of multiple causation, growth-aging influence, genetic influence, historic influence and conscious-unconscious activity. The theorems of summation of response and the inevitability of conscious-unconscious conflict with their corollaries follow directly from the axiomatic foundations, as does the existence of an adaptation-defense mechanism. The interpretation of the defense mechanism in terms of an ego-id feedback system provides the basis for the structural existence of conscious-conscious and unconscious-unconscious conflict.  相似文献   

19.
A genealogical interpretation of linkage disequilibrium   总被引:3,自引:0,他引:3  
McVean GA 《Genetics》2002,162(2):987-991
The degree of association between alleles at different loci, or linkage disequilibrium, is widely used to infer details of evolutionary processes. Here I explore how associations between alleles relate to properties of the underlying genealogy of sequences. Under the neutral, infinite-sites assumption I show that there is a direct correspondence between the covariance in coalescence times at different parts of the genome and the degree of linkage disequilibrium. These covariances can be calculated exactly under the standard neutral model and by Monte Carlo simulation under different demographic models. I show that the effects of population growth, population bottlenecks, and population structure on linkage disequilibrium can be described through their effects on the covariance in coalescence times.  相似文献   

20.
Almost all the information that is needed to specify thalamocortical and neocortical wiring derives from patterned electrical activity induced by the environment. Wiring accuracy must be limited by the anatomical specificity of the cascade of events triggered by neural activity and culminating in synaptogenesis. We present a simple model of learning in the presence of plasticity errors. One way to achieve learning specificity is to build better synapses. We discuss an alternative, circuit-based, approach that only allows plasticity at connections that support highly selective correlations. This circuit resembles some of the more puzzling aspects of thalamocorticothalamic circuitry.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号