Management of craniotomy in young rabbits

A safe and easy-to-manage technique for various craniotomy procedures in young rabbits has been developed. This technique, which minimizes the need for special instrumentation, has been tested in 90 animals with a minimal mortality and morbidity: one death perioperatively caused by sagittal sinus bleeding and one rabbit disclosing a brief period of postoperative illness, respectively. The technique, including postsurgical strategy, is described in detail.     

A conjugate of cellulase with fluorescein isothiocyanate: a specific stain for cellulose.

A fluorescent technique has been developed for in situ staining of cellulose. The staining agent in conjugate of cellulase and fluorescein isothiocyanate (FITC). Application of this agent does not disturb intercellular or intracellular substances. The technique depends on the specific binding of the fluorescent labeled enzyme to its substrate. The stain has been tested on cell-free noncellulose polysaccharides similar to cellulose and does not stain them. The technique has been used to localize cellulose during the life cycle of Dictyostelium discoideum with results that correspond to previous work using other methods.     

Incorporation of selenocysteine into proteins using peptide ligation

Expressed protein ligation has become a frequently used technique to insert non-standard amino acids into proteins. The technique has been adapted to insert selenocysteine residues in place of cysteine residue in proteins, taking advantage of the similarity in the chemistries of sulfur and selenium. This replacement can confer unique structural and catalytic properties to enzymes and proteins. The development of this technique also allows for naturally occurring selenoproteins to be produced semisynthetically.     

体细胞介导制备转基因动物的新途径

体细胞介导制备转基因动物的技术路线是在核移植技术的基础上建立起来的。它的问世不过只有四五年时间 ,但显示了其具有广泛的应用前景。本综述比较了不同制备转基因动物技术的优缺点 ,介绍了体细胞介导制备转基因动物的基本技术路线 ,着重阐述了体细胞转染和整合细胞的克隆 ,以及体细胞介导的转基因技术的局限性和应用前景     

Measurements of total body calcium by prompt-gamma neutron activation abalysis using a252Cf source

A clinical neutron activation instrument has been developed for in vivo elemental analysis. Utilizing the prompt-capture gamma ray technique, simultaneous total body (TB) measurements of primarily Ca, but also Cl, N, C, and H are routinely performed. This paper describes a technique for the measurement of TBCa (g) that relies on the use of TBCl as an internal standard. The method has been tested with four anthropomorphic phantoms covering a range of body habitus. The mean discrepancy between the measured and known Ca contents was 3.6%. The technique has been applied to two patient groups, and encouraging results were obtained.     

Direct visualization of collagens and procollagens in polyacrylamide gels.

This report describes a procedure that results in the rapid visual identification of collagens and procollagens in polyacrylamide gels. The technique results in a pink stain for collagenous proteins and a blue stain for all other proteins. The color difference has been evaluated spectrophotometrically. The absorbance maxima for collagen-Coomassie blue R250 complexes in gels is 520–535 nm, and the maxima for all other protein-Coomassie blue R250 complexes that we tested is 550–560 nm. This technique will facilitate the identification of collagenous proteins in complex mixtures of proteins derived from cell membranes, whole cell extracts, conditioned media, and extracellular matrices. We use the technique to detect procollagens in human diploid fibroblast conditioned media. The technique is simple, relatively rapid, has utility for proteins extracted by a variety of methods, and is applicable to all polyacrylamide gel systems in general use.     

应用PCR技术检测串珠镰刀菌

串珠镰刀菌(Fusarium moniliform)是一种危害严重、在世界各地广泛流行的植物病原真菌,当前对串珠镰刀菌的鉴定主要根据其菌丝体及再生菌丝的形态结构学特征及染病作物的病害症状来进行鉴定。这些鉴定方法相对简单并在很大程度上依赖于经验,受主观因素影响较大。采用串珠镰刀菌种特异性的寡聚核苷酸为引物,运用PCR技术对串珠镶刀菌进行检测是一种快速可靠的检测鉴定方法,它无需病原菌的分离培养纯化,能从感病的玉米组织中直接实现对串珠镰刀菌的快速检测。经对霉变玉米样品和玉米穗腐病组织的检测,证明该方法是一种快建、有效的方法,具有重要的实际应用价值。     

Using the operonic gene pairs for establishing the treshold for correlation coefficient of differently expressed genes

We developed an approach for effective estimating the correlations in the noise component of gene expression data. An efficent noise reduction technique has been suggested. The resulting technique has been applied to E. coli microarray data and tested on SOS response modulated genes.     

Dispelling the myths and misconceptions about transumbilical breast augmentation

Since its invention in 1991, the transumbilical breast augmentation (TUBA) technique has gained popularity, and it has been proven safe and effective. In addition, the technique has several advantages over other methods of breast augmentation. Nevertheless, the method has often been the subject of a great variety of criticisms. Careful examination of those criticisms reveals that most are, in fact, untrue; they are misconceptions at best and falsehoods at worst. In this article, the author examines the 20 most common misconceptions about this procedure, clarifies or corrects them as appropriate, and suggests possible reasons for their having arisen in the first place. In addition, the actual drawbacks of the technique are reviewed. The author also outlines what he considers to be the criteria necessary for a surgeon to criticize any technique being used successfully by others: the surgeon must have proper plastic surgical training and certification, have completed training in the specific technique, and have a personal experience with performing a minimum number of cases.     

实时定量PCR技术及应用

实时定量PCR(Real-tim e Quantitative Polym erase Chain Reaction,RQ-PCR),是20世纪90年代中期发展起来的基于PCR技术的利用不同的荧光检测来给核酸定量的技术。克服了传统PCR的许多不足,能准确敏感地检测模板浓度,DNA拷贝数和检测基因变异。综述了RQ-PCR技术的原理,RQ-PCR实时定量检测系统及应用。     

A collaborative investigation of a potency assay for adsorbed tetanus vaccines based on the protection of mice from tetanic paralysis

A quantal technique for the potency assay in mice of adsorbed tetanus vaccines which uses paralysis as the criterion of a failure of protection is described. The results of the technique are compared with those provided by the more orthodox technique which uses death as the criterion of a failure of protection. The paralytic technique provides results comparable with those provided by the lethal technique and has the advantage that it may be used in a way that almost wholly eliminates animal suffering.     

Bacteriosorption reaction on a smooth surface for detecting antibodies and antigens

The solid-phase technique for the detection of antibodies and antigens has been developed and named the bacteriosorption test. The test is based on binding staphylococci containing protein A with the Fc-regions of IgG-antibodies attached to antigens immobilized on polystyrene. The possibilities of this technique have been analyzed with the use of diphtheria toxoid, house-dust allergen and homologous rabbit antisera. In the detection of antibodies the proposed test is not inferior to the passive hemagglutination test, and its sensitivity in the detection of antigens by the sandwich technique reaches 0.05-0.1 micrograms/ml. The specificity of the technique has been experimentally confirmed by the inhibition of the reaction with soluble antigen and staphylococcal protein A. The variability factor of the technique does not exceed 10%.     

Densitometric analysis of dental implant placement between flapless technique and the two-stage technique--a pilot study

Flapless technique is a surgical approach of implant placement without raising a mucoperiosteal flap. Such approach has many advantages: shorter surgical treatment, minimal bleeding, postoperative discomfort for the patient is reduced; possibility of immediate loading of the inserted implant, faster procedure of implant placement and by that less time is needed for the complete implant-prosthetic restoration. Purpose of this pilot study was radiographic assessment of flapless technique and determination of its clinical values in comparison with two-stage dental implant technique through computerized densitometric analysis. The sample consisted of 10 patients with missing teeth in the premolar region in the upper jaw. An implant was placed in that position. In the first group of 5 patients the implants were inserted with the flapless technique, and in the other group of 5 patients implant insertion was done with a two-stage technique. All inserted implants were loaded with metal-ceramic crowns 3 months after placement. The patients were followed for 18 months through clinical follow-ups and radiovisiographical (RVG) images made after 3, 12 and 18 months. After comparing the average densities, the results showed similar decrease of density in both groups, conventional two-stage technique showed 3.24 and flapless technique 1.23. It can be concluded that flapless technique in everyday clinical usage has the same result as the two-stage dental implant technique.     

Nuclear corrosion monitoring—

Nuclear corrosion technique has been developed for the assay of various heavy metals released through corrosion and abrasion into electrolytes from various biomaterials like amalgams, chromium— cobalt and gold alloys, steel, and titanium. Application of the technique in measurement of selective release rates under static or dynamic conditions, i.e., during cyclic loading, is discussed. The elements chromium, cobalt, copper, gold, iron, mercury, molybdenum, silver, titanium, and zinc have been quantitatively assessed. In vivo corrosion measurements are further included. By combining the present nuclear tracer technique with ESCA technique, knowledge about reaction mechanisms occurring at the interface solid/liquid is obtained. Exposure of humans to various heavy metals from biomaterials, e.g., dental materials, can be estimated using the NCM technique. The technique also has a potential for selective release measurements of several nuclides possessing suitable radioanalytical properties from other types of alloys immersed in various liquid environments.     

A methodology for rapid detection of Salmonella typhimurium using label-free electrochemical impedance spectroscopy

A pathogen detection methodology based on Bayesian decision theory has been developed for rapid and reliable detection of Salmonella typhimurium. The methodology exploits principles from statistical signal processing along with impedance spectroscopy in order to analytically determine the existence of pathogens in the target solution. The proposed technique is validated using a cost-effective and portable immunosensor. This device uses label-free, electrochemical impedance spectroscopy for pathogen detection and has been demonstrated to reliably detect pre-infectious levels of pathogen in sample solutions. The detection process does not entail any pathogen enrichment procedures. The results using the proposed technique indicate a detection time of approximately 6min (5min for data acquisition, 1min for analysis) for pathogen concentrations in the order of 500CFU/ml. The detection methodology presented here has demonstrated high accuracy and can be generalized for the detection of other pathogens with healthcare, food, and environmental implications. Furthermore, the technique has a low computational complexity and uses a minimal data-set (only 30 data-samples) for data analysis. Hence, it is ideal for use in hand-held pathogen detectors.     

Simultaneous determination of specific antigen, antibody and immune complexes in the serum of patients with chronic schistosomiasis

The main steps of a sensitive and quantitative technique for the simultaneous determination, in the same microplate, of antigen, antibody and specific immune complexes has been described. The assay involved principles of the double sandwich technique used in the "Enzyme-Linked Immunosorbent Assay" (ELISA). The technique proved to be useful for the estimation of antigen, antibody and specific immune complexes in sera of patients with human chronic hepato-intestinal schistosomiasis.     

PCR-SSCP技术在微生物检测中的应用

聚合酶链式反应-单链构象多态性(PCR-SSCP)是一种能够检测DNA突变的分子生物学分析技术,具有快速、简便、灵敏与适于大样本筛选的特点,近年来被广泛应用于生命科学领域的研究。对PCR-SSCP技术在微生物检测研究领域的应用和发展作简要的介绍。     

Isolation of the equilibrium solution from a west soil or clay paste

Summary A technique is described for the isolation of the equalibrium solution of very small amounts of soil. The technique is a combination of the filter-paper and centrifugation techniques. The new technique has been compared with the saturation-extract method with good results.     

Cardiac output monitoring by echocardiography: should we pass on Swan-Ganz catheters?

Transesophageal echocardiography offers a noninvasive technique for the continuous monitoring of cardiac performance. The combination of 2-dimensional echocardiography and Doppler velocitometry provide assessment of cardiac anatomy, valve function and, ventricular loading conditions. Although transesophageal echocardiography has become accepted for perioperative monitoring, it is typically used in conjunction with Swan-Ganz catheterization. To supplant Swan-Ganz catheters, an echocardiographic technique to monitor cardiac output is necessary. Despite considerable effort to achieve this goal, a satisfactory technique has been difficult to realize. This paper discusses the role of cardiac output monitoring in perioperative care and critically examines echocardiographic techniques for cardiac output monitoring.