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1.
The classical degree function constructed earlier for pseudomonotone mappings has been used to develop a broader degree theory of classical type for the sum of a maximal monotone map from a reflexive Banach space to its dual together with a bounded pseudomonotone map. The proof uses the generalized Yosida approximation of the maximal monotone mapping.  相似文献   

2.
A classical degree function is constructed for pseudomonotone mappings from a reflexive Banach space to its dual, using Galerkin approximations. This generalizes the Leray-Schauder degree when the Banach space is a Hilbert space and yields a flexible analytical tool for the study of nonlinear elliptic problems of higher order in divergence form.  相似文献   

3.
We have used a modified linking clone strategy and pulsed-field gel electrophoresis to derive a map of the 29 Sfi I and 4 Not I sites in the 10 million base pair genome of the protozoan parasite Theileria parva. This was achieved in the absence of classical genetic information. The map reveals four chromosomes. Several genes, including those for parasite antigens, have been located on the map, as has the single locus carrying the major repetitive sequence in this organism. The map forms the basis for a study of sexual recombination in T. parva, which will be of importance in the application of present methods of immunization. Aspects of the mapping strategy may be useful in the study of other small eukaryotic genomes.  相似文献   

4.
5.
A population of Arabidopsis thaliana recombinant inbred lines was constructed and used to develop a high-density genetic linkage map containing 252 random amplified polymorphic DNA markers and 60 previously mapped restriction fragment length polymorphisms. Linkage groups were correlated to the classical genetic map by inclusion of nine phenotypic markers in the mapping cross. We also applied a technique for local mapping that allows targeting of markers to a selected genome region by pooling DNA from recombinant inbred lines based on their genotype. We conclude that random amplified polymorphic DNAs, used in conjunction with a recombinant inbred population, can facilitate the genetic and physical characterization of the Arabidopsis genome and that this method is generally applicable to other organisms for which appropriate populations either are available or can be developed.  相似文献   

6.
ST-T isointegral analysis of body surface mapping was used in an attempt to localize ischemic areas on exercise tests. In 28 patients with angina pectoris and 10 healthy subjects, body surface potential was recorded with 87 leads, and ST isopotential and ST-T isointegral maps were constructed. In all 10 healthy subjects, the basic pattern of the ST-T isointegral map showed no significant change after exercise. In 23 of 28 patients with angina pectoris (82%), alterations in the ST-T isointegral map after exercise were observed. They were divided into four types (anterior, inferoposterior, lateral, and global) according to the distribution of negative values, which were well correlated with the extent of ischemic area determined by thallium myocardial scintigraphy and coronary angiography. The postexercise ST-T isointegral map was normalized after administration of nitroglycerin in four of five patients. In five patients (18%) who did not show abnormalities on the postexercise ST-T isointegral map, the magnitude of maximal ST depression was significantly smaller than that observed in the other 23 patients with angina pectoris (0.14 vs 0.23 mV on the average, p less than 0.05). It was concluded that the exercise test with ST-T isointegral mapping is a new method for noninvasive detection of location and severity of ischemic regions.  相似文献   

7.
Electrocardiographic body surface mapping on admission to coronary care has been shown to predict prognosis in a previous study of 100 patients with inferior wall acute myocardial infarction (AMI). A further 98 patients with first inferior wall AMI were now studied by body surface mapping on admission to coronary care to confirm that both the spatial distribution or map pattern of ST-segment potentials and the precise measurement of the maxima and minima are of prognostic significance. Each ST-segment map was compared by correlation coefficient to the average map pattern of the 4 groups derived in a previous study and placed in the group with the highest correlation coefficient. Analysis of these groups against outcome confirmed that the group dominated by a large area of marked anterior ST depression was associated with a high rate of complications and a significantly lower survival free of coronary artery bypass grafting (p less than 0.01). Patients in this group had more extensive and severe coronary artery disease than patients in the other groups. Increasing values of maximal ST depression correlated with mortality and complication rates. The extent by which the magnitude of ST-segment depression exceeded the magnitude of ST-segment elevation correlated with mortality and incidence of left ventricular failure. The results confirm the findings of the original study. Body surface mapping is of prognostic significance in inferior wall AMI.  相似文献   

8.
OBJECTIVES: This study was directed at developing spatial 62-lead electrocardiogram (ECG) criteria for classification of counterclockwise (CCW) and clockwise (CW) typical atrial flutter (Fl) in patients with and without structural heart disease. BACKGROUND: Electrocardiographic classification of CCW and CW typical atrial Fl is frequently hampered by inaccurate and inconclusive scalar waveform analysis of the 12-lead ECG. METHODS: Electrocardiogram signals from 62 torso sites and multisite endocardial recordings were obtained during CCW typical atrial Fl (12 patients), CW typical Fl (3 patients), both forms of typical Fl (4 patients) and CCW typical and atypical atrial Fl (1 patient). All the Fl wave episodes were divided into two or three successive time periods showing stable potential distributions from which integral maps were computed. RESULTS: The initial, intermediate and terminal CCW Fl wave map patterns coincided with: 1) caudocranial activation of the right atrial septum and proximal-to-distal coronary sinus activation, 2) craniocaudal activation of the right atrial free wall, and 3) activation of the lateral part of the subeustachian isthmus, respectively. The initial, intermediate and terminal CW Fl wave map patterns corresponded with : 1) craniocaudal right atrial septal activation, 2) activation of the subeustachian isthmus and proximal-to-distal coronary sinus activation, and 3) caudocranial right atrial free wall activation, respectively. A reference set of typical CCW and CW mean integral maps of the three successive Fl wave periods was computed after establishing a high degree of quantitative interpatient integral map pattern correspondence irrespective of the presence or absence of organic heart disease. CONCLUSIONS: The 62-lead ECG of CCW and CW typical atrial Fl in man is characterized by a stereotypical spatial voltage distribution that can be directly related to the underlying activation sequence and is highly specific to the direction of Fl wave rotation. The mean CCW and CW Fl wave integral maps present a unique reference set for improved clinical detection and classification of typical atrial Fl.  相似文献   

9.
To evaluate the spatial distribution of flow velocities, turbulence and spatial acceleration in serial tunnel-valve obstruction, Doppler color flow mapping was performed in a pulsatile flow model with a tunnel obstruction (1.0 or 1.5 cm2) inserted at 2, 20 and 40 mm proximal to a mildly stenotic bioprosthetic valve studied at flow rates of 1, 2.7 and 4.9 liters/min. Measured pressure gradients were consistently higher across the tunnel (mean +/- SD 32.7 +/- 26.5 mm Hg) than across the tunnel plus valve (28.8 +/- 26.9 mm Hg, p less than 0.01). Doppler color flow map images were analyzed using a Sony RGB video-digitizing computer, providing numerical velocity assignments for the blue, red and green (variance) pixel components to allow the flow maps to be constructed into digital velocity maps and pseudo three-dimensional velocity maps. The maximal velocity stream extended distal to the tunnel (2 to 19 mm), and the length of this extension correlated well with the pressure gradient measured across the tunnel (r = 0.89), with a rapidly decelerating and turbulent spray area seen immediately distal to the valve. Pressure gradient calculated from the maximal velocity derived from the color flow map, which could only be estimated from the velocity maps for the 1.5 cm2 tunnel, correlated well with the gradient measured across the tunnel (18.0 +/- 14.1 versus 19.2 +/- 14.5 mm Hg, respectively, r = 0.98). Acceleration was seen proximal to both tunnels.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
A whole genome cattle-hamster radiation hybrid cell panel was used to construct a map of 54 markers located on bovine chromosome 5 (BTA5). Of the 54 markers, 34 are microsatellites selected from the cattle linkage map and 20 are genes. Among the 20 mapped genes, 10 are new assignments that were made by using the comparative mapping by annotation and sequence similarity strategy. A LOD-3 radiation hybrid framework map consisting of 21 markers was constructed. The relatively low retention frequency of markers on this chromosome (19%) prevented unambiguous ordering of the other 33 markers. The length of the map is 398.7 cR, corresponding to a ratio of approximately 2.8 cR(5,000)/cM. Type I genes were binned for comparison of gene order among cattle, humans, and mice. Multiple internal rearrangements within conserved syntenic groups were apparent upon comparison of gene order on BTA5 and HSA12 and HSA22. A similarly high number of rearrangements were observed between BTA5 and MMU6, MMU10, and MMU15. The detailed comparative map of BTA5 should facilitate identification of genes affecting economically important traits that have been mapped to this chromosome and should contribute to our understanding of mammalian chromosome evolution.  相似文献   

11.
The zebrafish is an excellent genetic system for the study of vertebrate development and disease. In an effort to provide a rapid and robust tool for zebrafish gene mapping, a panel of radiation hybrids (RH) was produced by fusion of irradiated zebrafish AB9 cells with mouse B78 cells. The overall retention of zebrafish sequences in the 93 RH cell lines that constitute the LN54 panel is 22%. Characterization of the LN54 panel with 849 simple sequence length polymorphism markers, 84 cloned genes and 122 expressed sequence tags allowed the production of an RH map whose total size was 11,501 centiRays. From this value, we estimated the average breakpoint frequency of the LN54 RH panel to correspond to 1 centiRay = 148 kilobase. Placement of a group of 235 unbiased markers on the RH map suggests that the map generated for the LN54 panel, at present, covers 88% of the zebrafish genome. Comparison of marker positions in RH and meiotic maps indicated a 96% concordance. Mapping expressed sequence tags and cloned genes by using the LN54 panel should prove to be a valuable method for the identification of candidate genes for specific mutations in zebrafish.  相似文献   

12.
In this note we present two new theorems concerning the solvability of nonlinear equations in normed linear spaces involving either K-coercive pseudo-A-proper mappings (Theorem 1) or their uniform limits (Theorem 2). These theorems are then used to obtain certain known as well as new existence results for various special classes of equations involving, for example, A-proper and P-compact operators; K-monotone, quasi-K-monotone and pseudo-K-monotone operators; monotone and others.  相似文献   

13.
Proteomic mapping provides powerful insights into functional myelin biology   总被引:1,自引:0,他引:1  
Myelin is a dynamic, functionally active membrane necessary for rapid action potential conduction, axon survival, and cytoarchitecture. The number of debilitating neurological disorders that occur when myelin is disrupted emphasizes its importance. Using high-resolution 2D gel electrophoresis, mass spectrometry, and immunoblotting, we have developed an extensive proteomic map of proteins present in myelin, identifying 98 proteins corresponding to at least 130 of the approximately 200 spots on the map. This proteomic map has been applied to analyses of the localization and function of selected proteins, providing a powerful tool to investigate the diverse functions of myelin.  相似文献   

14.

Purpose

Conventional electroanatomical mapping systems employ roving catheters with one or a small number of electrodes. Maps acquired using these systems usually contain a small number of points and take a long time to acquire. Use of a multielectrode catheter could facilitate rapid acquisition of higher-resolution maps through simultaneous collection of data from multiple points in space; however, a large multielectrode array could potentially limit catheter maneuverability. The purpose of this study was to test the feasibility of using a novel, multielectrode catheter to map the right atrium and the left ventricle.

Methods

Electroanatomical mapping of the right atrium and the left ventricle during both sinus and paced rhythm were performed in five swine using a conventional mapping catheter and a novel, multielectrode catheter.

Results

Average map acquisition times for the multielectrode catheter (with continuous data collection) ranged from 5.2 to 9.5 min. These maps contained an average of 2,753 to 3,566 points. Manual data collection with the multielectrode catheter was less rapid (average map completion in 11.4 to 18.1 min with an average of 870 to 1,038 points per map), but the conventional catheter was slower still (average map completion in 28.6 to 32.2 min with an average 120 to 148 points per map).

Conclusions

Use of this multielectrode catheter is feasible for mapping the left ventricle as well as the right atrium. The multielectrode catheter facilitates acquisition of electroanatomical data more rapidly than a conventional mapping catheter. This results in shorter map acquisition times and higher-density electroanatomical maps in these chambers.  相似文献   

15.
A fast random cost algorithm for physical mapping.   总被引:3,自引:0,他引:3       下载免费PDF全文
Ordering clones from a genomic library into physical maps of whole chromosomes presents a central computational/statistical problem in genetics. Here we present a physical mapping algorithm for creating ordered genomic libraries or contig maps by using a random cost approach [Berg, A. (1993) Nature (London) 361, 708-710]. This random cost algorithm is 5-10 times faster than existing physical mapping algorithms and has optimization performance comparable to existing procedures. The speedup in the algorithm makes practical the widespread use of bootstrap resampling to assess the statistical reliability of links in the physical map as well as the use of more elaborate physical mapping criteria to improve map quality. The random cost algorithm is illustrated by its application in assembling a physical map of chromosome IV from the filamentous fungus Aspergillus nidulans.  相似文献   

16.
We have constructed a map of the "protein structure space" by using the pairwise structural similarity scores calculated for all nonredundant protein structures determined experimentally. As expected, proteins with similar structures clustered together in the map and the overall distribution of structural classes of this map followed closely that of the map of the "protein fold space" we have reported previously. Consequently, proteins sharing similar molecular functions also were found to colocalize in the protein structure space map, pointing toward a previously undescribed scheme for structure-based functional inference for remote homologues based on the proximity in the map of the protein structure space. We found that this scheme consistently outperformed other predictions made by using either the raw scores or normalized Z-scores of pairwise DALI structure alignment.  相似文献   

17.
目的 用体表心电标测时空图法探讨复极离散空间分布和临床价值。方法 采用体表心电标测时空图法及12导联心电图 ,分别测定 6 8例急性心肌梗死 (AMI)患者的QT间期及QT离散度 (QTd) ,并与 5 8例正常对照者进行对比。结果  (1)在正常人及AMI患者时空图法测得QTd均大于 12导联心电图 ,两种方法均表明AMI后QTd增加。 (2 )正常人时空图分布 :T波呈单群、结束时间相对较一致 ;AMI后时空图分布发生明显变化 :梗死区对应体表部位T波结束延长 ,大致分 3型 ,部分患者可见零线垂直偏斜 ,ST T复极过程中分群现象 ,T波结束离散增大。 (3)AMI患者死亡及合并室性心律失常者时空图法测得QTd较无心律失常者增加、分布主要表现第Ⅰ、Ⅲ型 (18/ 2 1) ,12导联心电图未发现两组间差异。 (4 )时空图尚可展示相邻部位的复极离散和U波分布。结论 时空图法可直观反映QT间期空间分布及离散 ,并能有效鉴别U波 ,可能会成为QTd研究中一项有前途的方法  相似文献   

18.
Deletion mapping of HLA and chromosome 6p genes.   总被引:5,自引:3,他引:2       下载免费PDF全文
We have analyzed a set of heterozygous mutants with deletions that encompass parts of HLA and surrounding regions of chromosome 6p. By a combination of Southern blotting, serologic, enzymatic, and cytogenetic analyses, we have ordered eight independent deletion break points into a sequence that divides chromosome 6p into six regions. The deletion mutants have been used in conjunction with the Southern blot technique to map HLA and other 6p gene probes into those regions. On the basis of these and other data we propose a genetic and physical map of HLA and surrounding regions of chromosome 6p. We find that for HLA probes, most of which hybridize with more than one gene, the multiple copies recognized by single probes map to single regions. Any chromosome 6p gene can now be regionally mapped by using these mutants.  相似文献   

19.
The development of saturated linkage maps using transferable markers, restriction fragment length polymorphisms, and micro-satellites has provided a foundation for fruit tree genetics and breeding. A Prunus reference map with 562 such markers is available, and a further set of 13 maps constructed with a subset of these markers has allowed genome comparison among seven Prunus diploid (x = 8) species (almond, peach, apricot, cherry, Prunus ferganensis, Prunus davidiana, and Prunus cerasifera); marker colinearity was the rule with all of them. Preliminary results of the comparison between apple and Prunus maps suggest a high level of synteny between these two genera. Conserved genomic regions have also been detected between Prunus and Arabidopsis. By using the data from different linkage maps anchored with the reference Prunus map, it has been possible to establish, in a general map, the position of 28 major genes affecting agronomic characters found in different species. Markers tightly linked to the major genes responsible for the expression of important traits (disease/pest resistances, fruit/nut quality, self-incompatibility, etc.) have been developed in apple and Prunus and are currently in use for marker-assisted selection in breeding programs. Quantitative character dissection using linkage maps and candidate gene approaches has already started. Genomic tools such as the Prunus physical map, large EST collections in both Prunus and Malus, and the establishment of the map position of high numbers of ESTs are required for a better understanding of the Rosaceae genome and to foster additional research and applications on fruit tree genetics.  相似文献   

20.
INTRODUCTION: Atrial arrhythmias have emerged as a topic of great interest for clinical electrophysiologists. Noninvasive imaging of electrical function in humans may be useful for computer-aided diagnosis and treatment of cardiac arrhythmias, which can be accomplished by the fusion of data from ECG mapping and magnetic resonance imaging (MRI). METHODS AND RESULTS: In this study, a bidomain-theory-based surface heart model activation time (AT) imaging approach was applied to paced rhythm data from four patients. Pacing sites were the right superior pulmonary vein, left inferior pulmonary vein, left superior pulmonary vein, coronary sinus, posterior wall of right atrium, and high right atrium. For coronary sinus pacing, the AT pattern of the right atrium was compared with a CARTO map. The root mean square error between CARTO geometry (85 nodal points) and the surface model of the right atrium was 8.6 mm. The correlation coefficient of the noninvasively obtained AT map of the right atrium and the CARTO map was 0.76. All pulmonary vein pacing sites were identified. The reconstructed pacing site of right posterior atrial pacing correlates with the invasively determined pacing catheter position with a localization distance of 4 mm. CONCLUSION: The individual anatomic model of the atria of each patient enables accurate noninvasive AT imaging within the atria, resulting in a localization error for the pacing sites within 10 mm. Our findings may have implications for imaging of atrial activity in patients with focal arrhythmias or focal triggers.  相似文献   

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