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1.
Capillary electrophoresis (CE) is an extremely sensitive technique, which has been used in the clinical laboratory for almost 10 yr. The components of CE instrumentation are described, as are injection modes, buffers, and effects of electroosmotic flow. The modes of separation used in CE, namely, capillary zone electrophoresis, capillary isoelectric focusing, capillary isotachophoresis, and micellar electrokinetic capillary chromatography, are explained. References for 26 different clinical applications of CE are included, among them assays that are used routinely as well as niche assays for specialized applications of CE. Verification of CE assays, current instrumentation, and future development of CE in the clinical laboratory are addressed.  相似文献   

2.
This paper describes a finite element scheme for realistic muscle-driven simulation of human foot movements. The scheme is used to simulate human ankle plantar flexion. A three-dimensional anatomically detailed finite element model of human foot and lower leg is developed and the idea of generating natural foot movement based entirely on the contraction of the plantar flexor muscles is used. The bones, ligaments, articular cartilage, muscles, tendons, as well as the rest soft tissues of human foot and lower leg are included in the model. A realistic three-dimensional continuum constitutive model that describes the biomechanical behaviour of muscles and tendons is used. Both the active and passive properties of muscle tissue are accounted for. The materials for bones and ligaments are considered as homogeneous, isotropic and linearly elastic, whereas the articular cartilage and the rest soft tissues (mainly fat) are defined as hyperelastic materials. The model is used to estimate muscle tissue deformations as well as stresses and strains that develop in the lower leg muscles during plantar flexion of the ankle. Stresses and strains that develop in Achilles tendon during such a movement are also investigated.  相似文献   

3.
This article presents a prototype of a surface-enhanced Raman spectroscopy (SERS)-encoded magnetic bead of 8 μm diameter. The core part of the bead is composed of a magnetic nanoparticle (NP)-embedded sulfonated polystyrene bead. The outer part of the bead is embedded with Ag NPs on which labeling molecules generating specific SERS bands are adsorbed. A silica shell is fabricated for further bioconjugation and protection of SERS signaling. Benzenethiol, 4-mercaptotoluene, 2-naphthalenethiol, and 4-aminothiophenol are used as labeling molecules. The magnetic SERS beads are used as substrates for protein sensing and screening with easy handling. As a model application, streptavidin-bound magnetic SERS beads are used to illustrate selective separation in a flow cytometry system, and the screened beads are spectrally recognized by Raman spectroscopy. The proposed magnetic SERS beads are likely to be used as a versatile solid support for protein sensing and screening in multiple assay technology.  相似文献   

4.
This paper describes a finite element scheme for realistic muscle-driven simulation of human foot movements. The scheme is used to simulate human ankle plantar flexion. A three-dimensional anatomically detailed finite element model of human foot and lower leg is developed and the idea of generating natural foot movement based entirely on the contraction of the plantar flexor muscles is used. The bones, ligaments, articular cartilage, muscles, tendons, as well as the rest soft tissues of human foot and lower leg are included in the model. A realistic three-dimensional continuum constitutive model that describes the biomechanical behaviour of muscles and tendons is used. Both the active and passive properties of muscle tissue are accounted for. The materials for bones and ligaments are considered as homogeneous, isotropic and linearly elastic, whereas the articular cartilage and the rest soft tissues (mainly fat) are defined as hyperelastic materials. The model is used to estimate muscle tissue deformations as well as stresses and strains that develop in the lower leg muscles during plantar flexion of the ankle. Stresses and strains that develop in Achilles tendon during such a movement are also investigated.  相似文献   

5.
Transcription of nucleosomes from human chromatin.   总被引:3,自引:3,他引:0       下载免费PDF全文
  相似文献   

6.
The powerful concept of bioisosterism is presented as a method for selecting molecular groups for drug design and lead-compound development. Three group-structure characteristics are described for this purpose. The E-State value for an attached atom is used as a measure of electrotopological group impact. The volume of the group is estimated from counts of sigma, pi, and lone-pair n electrons, as embodied in the valence and simple connectivity delta values for atoms in the group. Polarity is described in terms of the polarity index Q(v). Specific examples are given for commonly used groups. Parameter spaces encoding these three attributes are presented as examples that may be used to guide bioisostere selection in late-stage drug-design procedures. The method presented here is of practical value in the decision processes of molecular modification.  相似文献   

7.
Hollow fibres with a symmetrical pore structure as used in artifical kidneys are tested for other purposes. The modules are shown to be suitable for the processing of enzymes such as thermitase, penicillin acylase, uratoxidase, and phosphatase by means of ultrafiltration and diafiltration. These hollow fibre modules are compared with other modules used in laboratory or in small technical devices. Similar values and material transfer coefficients are calculated.  相似文献   

8.
赵日瑾  胡笙 《昆虫知识》1992,29(3):184-186
<正> 在60年代以前,我国的螨类问题并不严重,由于广泛地应用有机氯,有机磷杀虫剂防治害虫,导致螨危害,在60~70年代逐步严重起来,使得害螨成为果树、棉花生产上的重要害虫。尤其是拟除虫菊酯在我国应用以来,因其高效、广谱,几乎可以杀死一切害虫,在我国应用发展很快。结果使得螨类危害问题更加严重,其主要原因是因为有机氯、有机磷、拟除虫菌酯类杀虫剂在防治植食性害虫的同时也大量的杀伤于各种天  相似文献   

9.
The techniques used for laparoscopic observation of reproductive systems in 23 species are described. The application of various techniques to biomedical research is examined, and the methods used for laparoscopic follicular aspiration and injection, as well as the techniques for uterine flushing collection from swine and nonhuman primates, and oviductal deposition of test solutions are described.  相似文献   

10.
四妙勇安汤加减治疗下肢脱疽的临床观察   总被引:1,自引:0,他引:1  
许德坚  李强  蒋三员 《蛇志》2006,18(2):98-99
目的总结中西医结合治疗下肢脱疽病的临床经验。方法应用四妙勇安汤加减内服,红萝卜加马齿苋水煎浸泡外洗患处;蚕食法清除坏死组织,外敷呋喃西林纱布保护伤口的综合治疗方法。结果36例中治愈27例,好转6例,无效3例。结论以四妙勇安汤加减内服为主的综合疗法是一种有效治疗方法,值得推广应用。  相似文献   

11.
This article presents an overview of the methods of bioanalysis of oxazaphosphorines, in particular, cyclophosphamide, ifosfamide, and trofosfamide as well as their metabolites. The metabolism of oxazaphosphorines is complex and leads to a large variety of metabolites and therefore the spectrum of methods used is relatively broad. The various methods used are shown in a table and the particularly important assays are described.  相似文献   

12.
研究维吾尔人利用植物的传统知识和经验,在社会经济发展和资源保护等方面具有潜在的应用价值。胡杨(Populus euphratica Oliv.)和灰叶胡杨(P.pruinosa Schrenk)是新疆沙漠生态系统的主要植物类群,研究采用关键人物访谈法,对胡杨和灰叶胡杨在新疆尉犁县维吾尔族民间的植物文化进行了研究。结果表明:胡杨和灰叶胡杨的胡杨碱白色结晶体在治疗胃胀、咽喉肿痛、胃溃疡、十二指肠溃疡及消化不良等方面有作用;胡杨碱黑色结晶体用于治疗腰疼、腿疼,有消肿及止痛等疗效;胡杨碱加工后作洗发膏和洗衣粉使用;胡杨水不仅治疗神经衰弱,有延缓衰老、降低高血压及高血脂的功效,还能降低心脏病发病率;胡杨和灰叶胡杨枝叶具有治疗家畜胃胀和肌胃腐烂病的作用。当地罗布人利用胡杨树来建设沙漠生态园及控制土壤沙漠化。研究初步揭示了两种胡杨植物与维吾尔人的植物文化体系,维吾尔族植物传统知识的研究,将对我国民族植物学的发展及多样性产生影响。  相似文献   

13.
The study on traditional knowledge and experience of using plants by Uyghurs folk people has a potential application in socio economic development and resource protection. Populus euphratica Oliv and Ppruinosa Schrenk are major plants in Taklimakan desert ecosystem of Xinjiang. This study aims to ascertain the Lopnur Uyghurs traditional knowledge on two Populus species and their cultural system related to these species. We investigated the key informants for interviews on using Populus plants. The Populus plants were used for various purposes. The white alkali crystals are using for the treatment of bloating, sore throat, stomach ulcers, duodenal ulcers and indigestion and also in soda, while black crystal is used for the treatment of back pain, leg pain, swelling and relieve pain. Alkali crystals are even used as shampoo after a simple processing and also as a laundry detergent. Populus plants water is applied as a treatment of neurasthenia. It is also used for anti aging, reducing blood pressure, high cholesterol and heart morbidity. Plants foliages are used as veterinary medicine such as bloating and rot of muscular and stomach of livestock. In addition, Lopnur people used the plants to build the Desert Ecological Park and controlling desertification. This article ascertained the two Populus speceis and Lopnur Uyghurs cultural system. Present study will improve the conservation of Lopnur Uyghurs folk indigenous/ traditional knowledge on Populus plants and to promote the sustainable development in the socio economic diversity.  相似文献   

14.
Efficient siRNA selection using hybridization thermodynamics   总被引:1,自引:1,他引:0       下载免费PDF全文
Small interfering RNA (siRNA) are widely used to infer gene function. Here, insights in the equilibrium of siRNA-target hybridization are used for selection of efficient siRNA. The accessibilities of siRNA and target mRNA for hybridization, as measured by folding free energy change, are shown to be significantly correlated with efficacy. For this study, a partition function calculation that considers all possible secondary structures is used to predict target site accessibility; a significant improvement over calculations that consider only the predicted lowest free energy structure or a set of low free energy structures. The predicted thermodynamic features, in addition to siRNA sequence features, are used as input for a support vector machine that selects functional siRNA. The method works well for predicting efficient siRNA (efficacy >70%) in a large siRNA data set from Novartis. The positive predictive value (percentage of sites predicted to be efficient for silencing that are) is as high as 87.6%. The sensitivity and specificity are 22.7 and 96.5%, respectively. When tested on data from different sources, the positive predictive value increased 8.1% by adding equilibrium terms to 25 local sequence features. Prediction of hybridization affinity using partition functions is now available in the RNAstructure software package.  相似文献   

15.
16.
Multivariate measures of similarity and niche overlap   总被引:1,自引:0,他引:1  
Niche overlap measures are used to assess the similarity in resource use by two species. Recently researchers have used niche overlap measures as summary measures and for making inferences, typically about competition for resources. The problem of estimating niche overlap when the niches are multivariate normal distributions with equal covariance matrices has previously been studied. In this work, the assumption of equal covariance matrices is relaxed. Two general measures of similarity are evaluated assuming general multivariate normal distributions. Commonly used measures of overlap are given as special cases of these two general measures. The question of bias in estimating these measures is discussed and shown to be a potential problem, especially when there are many redundant variables or if sample sizes are small.  相似文献   

17.
Gessner R  Rösch P  Kiefer W  Popp J 《Biopolymers》2002,67(4-5):327-330
The results for surface enhanced Raman scattering (SERS) studies on biological samples are reported. Etched and silver coated glass fiber tips were used as a SERS substrate. This method enabled the recording of spectra of biological samples, such as plant tissue or microbiological cells, with a high spatial resolution. Because of the low laser power used with the fiber tips, it was even possible to investigate tissues that are very sensitive toward laser power as it is used in a common micro-Raman setup.  相似文献   

18.
This article presents a brief history of masturbation. In particular, subjects such as masturbation in antiquity and the attitude of the church towards this practice are described, along with certain accessories used to facilitate masturbation. Preventive measures used in the past against masturbation are also described, as well as the various cures for the consequences of this vice. The two famous publications Onania and Onanism justifying the polemic against masturbation are also presented.  相似文献   

19.
Conjugated polymers (CPs) with large, delocalised molecular structures exhibit unique optical and electrochemical characteristics that can be used as excellent sensing elements. Recently, research on chemical and biological sensors that use water-soluble CPs as transducers has generated intense interest. Two main sensing mechanisms are used for the detection of DNA-related events, such as hybridisation, mismatch, single nucleotide polymorphism (SNP), SNP genotyping, conformational changes, and cleavage of the nucleic acids. One mechanism takes advantage of the fluorescence resonance energy transfer (FRET) between CPs and a chromophore label on the nucleic acid probes in which a series of cationic polyfluorene, polythiophene and polyarylene derivatives are frequently used. The other mechanism relies on the conformational effects of CPs, which is induced by combination of the specific targets in which cationic polythiophene derivatives are often used. The electron transfer property of CPs are always used to design high sensitive electrochemical DNA biosensors. Here we review recent progress in the development of optical and electrochemical DNA biosensors based on water-soluble CPs.  相似文献   

20.
Ferocactus histrix and Echinocactus platyacanthus are two common barrel cacti of the semiarid highlands of Central Mexico. In pre-Columbian times, these plants were sacred, used for sacrifices, food and medicine. Today, these cacti are used in the candy industry, as medicine, as a source of food and water for goats and as ornamental plants. The floral buds and fruits ofF. histrix are consumed by the local people; the latter are sold in local markets. Until recently, the apical indument ofE. platyacanthus was used for padding and weaving. The importance of these species increases with the aridity of the land and its inadequacy for agriculture. Habitat protection and artificial propagation are needed to avoid the extinction of these species.  相似文献   

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