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1.
Free tongue composite graft for correction of a vermilion defect 总被引:1,自引:0,他引:1
A case report of hemangioma of the vermilion border treated with excision and free composite tongue graft is presented. A technique of lip reconstruction utilizing a composite tongue graft in one step has been described. It constitutes an improvement over the tongue pedicle flap technique, which has been hitherto used and requires two stages. The indications and limitations of the technique have been discussed. 相似文献
2.
RNAi技术在昆虫功能基因研究中的应用进展 总被引:5,自引:1,他引:4
RNA干扰(RNA interference,RNAi)是指外源或内源的双链RNA(dsRNA)特异性地引起基因表达沉默的现象,它作为一种有效的工具用来产生转录后沉默,从而抑制特定基因的表达,成为基因功能研究的一种新方法,除了在模式昆虫如果蝇Drosophila中广泛应用之外,也在非模式昆虫中得到成功应用。近年来,RNAi技术在导入方法和基因功能分析方面都取得了飞速发展,且与转基因技术相结合成功应用于害虫防治领域。本文综述了RNAi技术在导入方法、昆虫功能基因组功能分析及害虫防治等领域新近的研究成果,并展望了该技术的应用前景。 相似文献
3.
The bacterial sensing system has been studied on three levels. First, a quantitative method has been devised for measuring the “action spectrum” of the bacterium in response to a sudden addition of attractant. Second, a technique has been developed for the rapid isolation of mutants defective in the transmission part of the sensing system. Third, a study of the effects of light on the transmission system reveals two components, one which generates tumbling and another which inhibits it. 相似文献
4.
The use of the "saline float" technique has enabled us to more easily position the foam-covered breast implants through a short aesthetic incision. Of 34 patients in whom this has been used, one breast has been complicated by wrinkling of the prosthesis noted early after surgery. At 6 months this is no longer evident. Retained saline has caused no problems, and no infections have been encountered. This technique offers a safe and simple solution to overcome the tissue friction associated with use of the polyurethane foam-covered prosthesis. 相似文献
5.
Although many age determination techniques have been developed for four of the five vertebrate classes, none has been developed to determine ages of adult birds. Here we report a technique, involving counting endosteal layers in the tibia, that has allowed us accurately to determine the age (in years) of 12 dead birds of species in four different families, Fulmar Fulmarus glacialis, Shag Phalacrocorax aristotelis, Redshank Tringa totanus and Great Skua Catharacta skua, all of which had been ringed as chicks and so were of known ages up to 16 years old, but provided inaccurate results for one species, the Common Guillemot Uria aalge. Since other bird species have been found to possess endosteal layers and no species has yet been found to lack such layers, this would appear to be a technique of general applicability which could permit invaluable new work in both pure and applied fields of ornithology. 相似文献
6.
In this, a preliminary report, the advantages and disadvantages of upper lobe lobectomy and concomitant thoracoplasty in tuberculosis have been summarized. There has been no undue increase in the operative hazard, there have been no complications, and the immediate results have been entirely satisfactory.Twenty-six patients were subjected to a combined operation (17 upper lobectomy-thoracoplasty and nine pneumonectomy-thoracoplasty) with one postoperative death. Indications for primary lobectomy have been discussed. The technique of resection and concomitant thoracoplasty has been briefly described. 相似文献
7.
In this, a preliminary report, the advantages and disadvantages of upper lobe lobectomy and concomitant thoracoplasty in tuberculosis have been summarized. There has been no undue increase in the operative hazard, there have been no complications, and the immediate results have been entirely satisfactory.Twenty-six patients were subjected to a combined operation (17 upper lobectomy-thoracoplasty and nine pneumonectomy-thoracoplasty) with one postoperative death.Indications for primary lobectomy have been discussed.The technique of resection and concomitant thoracoplasty has been briefly described. 相似文献
8.
I. A. Popov N. L. Starodubtseva M. I. Indeikina Yu. I. Kostyukevich A. S. Kononikhin M. I. Nikolaeva E. N. Kukaev S. A. Kozin A. A. Makarov E. N. Nikolaev 《Molecular Biology》2013,47(6):885-893
Transthyretin, one of the major blood proteins, displays a variety of posttranslational modifications, including those related to the development of grave diseases, such as Alzheimer’s disease, and familial amyloid polyneuropathy. A combined analytical technique based on the use of two mass spectrometric approaches (bottom-up and top-down) has been developed in the present study to determine the role of the modified forms of transthyretin in the progression of Alzheimer’s disease. The high efficiency of this technique has been demonstrated for ten serum samples obtained from patients diagnosed with Alzheimer’s disease and healthy volunteers. 相似文献
9.
在MR技术被临床应用的数十年其间,不断出现的新技术使信号采集速度和图象质量得到了很大的提高,其中之一的并行采集技术对信号采集速度的提高起了十分重要的作用。介绍了MR并行采集技术研究现状及临床应用情况,并对其存在的问题和发展前景进行了探讨。 相似文献
10.
Witch's chin is an unpleasant aesthetic defect characterized by ptosis of premental tissue and a deep submental fold, which may be exaggerated by hyperprojection of the mandible. These three elements determine the different degrees of deformity; therefore, the ideal treatment should be directed to one, two, or all three of them. Despite unanimity on the surgical approach of the defect, a large variety of techniques have been proposed by various authors. The need to use a technique suitable for different clinical pictures, characterized by a progressive surgical aggression, as usually performed in this practice, has led to standardize a technique to correct witch's chin, by means of three progressive steps, depending on the degree of deformity. The advantage of this procedure is that once a good result has been achieved, the subsequent steps may be omitted. The technique has been successfully performed in five patients, and the mean follow-up is 12 months. Figures from two representative cases are presented. 相似文献
11.
生物芯片技术及其应用 总被引:5,自引:0,他引:5
生物芯片是指包被在固相载体上的高密度DNA、抗原、抗体、细胞或组织的微点阵,它是微电子学和分子生物学结合产生的新技术。该技术被评为1998年度世界十大科技进展之一。本文讨论了生物芯片技术的发展、技术参数、相关仪器的发展和在DNA序列测定、基因表达分析、基因分型、基因多态性分析、疾病的诊断、突变分析、药物筛选和微生物的鉴定等方面的应用。 相似文献
12.
The aim of this literature review, which considers 47 articles published between 1989 and 2015, is to ascertain the current status of the active biomonitoring technique for assessing water quality and to evaluate the degree to which different aspects of the method have been standardized. Use of the tool is largely limited to Europe (83% of the articles reviewed). The technique has been used to biomonitor inorganic contaminants (in 96% of the studies) and, to a lesser extent, organic contaminants (4% of the studies). Only 25% of the articles concern methodological aspects of the technique. Moreover, most authors (78%) have only published one article on the topic, and many different protocols have been used in the various studies. As a result, the technique is not standardized, which hampers comparison of the results of different studies. We propose a protocol that would facilitate use of the technique for routine monitoring of the quality of river waters. 相似文献
13.
A method of energy minimization for conformational energy calculations using the least-squares technique has been reported. The method has been tested in the simple case of a pair of alanyl peptide units using the non-bonded potential energy. Starting from any point in the (φ, ψ) energy map (not necessarily near a minimum), convergence to one of the energy minima is achieved rapidly, within a few cycles of iteration. 相似文献
14.
15.
A charge pulse technique applied to the study of charge transfer at metal-solution interfaces has been used to determine the capacity and the conductance of a membrane bilayer at both zero time and zero voltage. The transport of hydrophobic ion across a glycerol-monooleate bilayer (tetraphenyl borate, picrate, dipicrylamine and tetraphenyl arsonium) has been investigated by this method. A theoretical approach to the problem has been proposed based on one analogous to that used for the compact double layer at metallic electrodes. 相似文献
16.
The replication pattern of a human inactive X chromosome reactivated for one to four genes by 5-azacytidine has been studied by the BrdU-33258-Hoechst-Giemsa technique in four subclones of a somatic hamster-human hybrid. In one of them the pattern was clearly modified. In the three others the changes were not significant. No correlation was found between expression and replication. 相似文献
17.
A charge pulse technique applied to the study of charge transfer at metal-solution interfaces has been used to determine the capacity and the conductance of a membrane bilayer at both zero time and zero voltage. The transport of hydrophobic ions across a glycerol-monooleate bilayer (tetraphenyl borate, picrate, dipicrylamine and tetraphenyl arsonium) has been investigated by this method. A theoretical approach to the problem has been proposed based on one analogous to that used for the compact double layer at metallic electrodes. 相似文献
18.
Rebecca A. Teeter 《Biometrical journal. Biometrische Zeitschrift》1985,27(7):759-773
In many situations one wishes to fit a piecewige regression which enables one to obtain estimates of the join points as well as the slopes and intercepts of the fitted submodels. This study developes a technique for fitting piecewise models to data which contain measurement error in an independent variable. The technique developed here combines the HUDSON (1966) procedure for estimating parameters in piecewise regression and the WALD (1940) Grouping Technique which obviates the problem of measurement error. If one assumes some knowledge of the position of the join point in relation to the data, methodology has been developed to estimate the parameters and study the asymptotic properties of the means and variances of the parameter estimates. However, in the more realistic case, when additional knowledge is limited, it is only possible to obtain the parameter estimates using an iterative technique (TEETER, 1982). The general technique for obtaining the join point estimate in the presence of measurement error is presented here and an example is given using data on women's basal body temperature during menstrual cycles. 相似文献
19.
Vihinen Mauno; Euranto Antti; Luostarinen Petri; Nevalainen Olli 《Bioinformatics (Oxford, England)》1992,8(1):35-38
An algorithm for multiple sequence comparison was implementedin FORTRAN 77 for VAX/VMS in GCG-atible format. The MULTICOMPprogram package includes several procedures with which one querysequence can be compared simultaneously to several DNA, RNAor amino acid sequences. The same technique was also introducedfor comparing propensities of secondary structural features,which can be predicted on the basis of amino acid sequences.The technique has been applied to a wide range of sequence andstructural analyses. 相似文献
20.
《Journal of molecular graphics》1990,8(1):45-51
A novel molecular mechanics technique, which is both computationally efficient and robust, for calculation of relative stability of macromolecules and binding energies is presented. The technique delivers exact results for a number of hypothetical systems; the technique can be used to energy minimize a number of similar macromolecules simultaneously; simultaneous minimization of many structures requires computer time only fractionally over that needed to energy minimize one such structure. The method has been used to successfully calculate the relative stability and binding of two avion lysozymes to the monoclonal antibody D1.3. 相似文献