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排序方式: 共有1147条查询结果,搜索用时 70 毫秒
81.
82.
V. I. Guz’ V. I. Markov A. A. Zaitsev V. A. Martynov A. B. Filonenko 《Radioelectronics and Communications Systems》2007,50(1):31-34
The paper presents a classification of contemporary methods for measurement of PAA characteristics, potentialities of their development and hardware implementation. The emphasis is made on diagnostic of PAA technical state, on determination of amplitude-phase distribution (APD) over the aperture, and on PAA adjustment procedures. The paper considers technical characteristics of automated measurement systems (AMS) and of the relevant equipment. Examples of AMS application for PAA parameter determination are included. 相似文献
83.
Fluorescent in situ hybridisation (FISH) is a powerful tool for the evaluation of chromosomal alterations in formalin fixed paraffin wax embedded sections of colorectal cancer. However, initial experiments using a two-step detection system for digoxigenin labelled chromosome specific centromeric probes resulted in a complete lack of hybridisation signal from a number of colorectal tumour sections. This was due to high levels of background autofluorescence observed in this tissue, which masked any relatively weak hybridisations present. To overcome this problem, a biotinylated tyramide mediated amplification system was incorporated into the FISH detection protocol. This involves the use of horseradish peroxidase to activate the biotinylated tyramide, resulting in the deposition of a large number of biotin molecules at the site of bound peroxidase, which corresponds directly to the location of hybridised probe. Final detection was by means of a streptavidin-FITC conjugate. Using this technique, a panel of 11 colorectal tumour samples studied to date have shown strong, specific hybridisation signals to the nucleus of tumour cells. Amplification of FISH signals by biotinylated tyramide has the potential to improve weak hybridisation signals in cells from numerous sources, using a variety of probe types, including single copy gene probes as well as centromere specific probes. 相似文献
84.
The asynchronous development of structural and metabolic disorders of aponeurosis, leading to the development of defects in sheath of the rectus abdominis is the major factor of hernia of linea alba formation. Development of diastasis of m. rectus abdominis is caused by primary structural and metabolic changes of myocytes caused by the extreme overload. The important factor of the operation is restoration of anatomic and physiologic parameters of the abdominal wall by bringing mm. rectus abdominis together, shortening and enforsing of aponeurosis makes it possible to distribute regularly the load on the aponeurotic sheath of musculi recti. 相似文献
85.
S ten Wolde F Engels AM Miltenburg EA Kuijpers GI Struijk-Wielinga BA Dijkmans 《Canadian Metallurgical Quarterly》1997,36(9):1012-1015
To investigate the potential anti-inflammatory effects of sesame oil, which is present in the injectable gold preparation Auromyose, the synthesis of tumour necrosis factor alpha (TNF-alpha), prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) by in vitro stimulated blood cells was measured before, during and after 12 weeks of dietary supplementation with 18 g of sesame oil daily in 11 healthy male volunteers. Neither TNF-alpha, PGE2 nor LTB4 production levels showed statistically significant changes during the 12 weeks of dietary supplementation with sesame oil. These results do not suggest an anti-inflammatory effect of sesame oil as present in injectable gold preparations which are used in the treatment of rheumatoid arthritis. 相似文献
86.
IV Ga?voronski? LP Tikhonova SV Chepur GI Nichiporuk 《Canadian Metallurgical Quarterly》1997,112(6):33-37
An original quantitative examination of oxidation-reduction enzymes activity in endotheliocytes of hemomicroclrculatory vessels of jejunum and rectum submucosal base in normal state and in portal hypertension was performed by the authors. Comparative analysis of the activity of the enzymes studied revealed different metabolic processes intensity in these organs, dependent on current hemodynamic conditions. Cytochemical changes in hemomicrocirculatory bed are consistent with structural reorganizations that arise in the wall of vessels studied, consist of several phases and may be used as an assessment criterion for defining the portal hypertension stage. 相似文献
87.
A. P. Amosov G. V. Bichurov Yu. M. Markov A. G. Makarenko 《Refractories and Industrial Ceramics》1997,38(11-12):431-434
The paper sums up studies into the production of nitride and carbonitride powders from inorganic azides by self-propagating high-temperature synthesis. Due to the high purity of such powders and the anisotropic or branched structure of their particles, it was possible to make a pore-free ceramic material withK lc=8–12 MPa·m1/2 without sintering activators. 相似文献
88.
V. G. Petrov A. Yu. Malyshev A. A. Petrov V. K. Markov 《Instruments and Experimental Techniques》2011,54(4):596-597
An instrument for fringe-jumps free measurements of the electron concentration and estimations of the peaking factor of density
distributions in magnetic confinement plasma devices with probing at frequencies close to the cutoff is described. The instrument
is intended to perform measurements in a 5 × 1018–1020 m−3 density range (while probing by the extraordinary wave) with time resolution ∼10 μs. 相似文献
89.
V. Ph. Markov H. N. Mukhamedzyanov L. N. Maskaeva Z. I. Smirnova 《Semiconductors》2011,45(11):1404-1407
Photoelectric characteristics of films of the Pb0.902Sn0.098Se solid solution based on the four-layer (SnSe-PbSe)2 composition obtained by layer-by-layer hydrochemical synthesis with subsequent heat treatment in air within the temperature
range 523–700 K are investigated. The measurements are performed in the temperature range 220–300 K. The thermal and optical
band gaps, temperature coefficient of the optical band gap, dark resistance, volt-watt sensitivity, and spectral characteristics
are determined. It is established that, at heat treatment temperatures below 573 K, the conductivity of the four-layer (SnSe-PbSe)2 compositions is characteristic of metals, while at higher temperatures, it is characteristic of p-type semiconductors. 相似文献
90.
GI Cubero JJ Reguero A Batalla E Simarro IS Posada S Braga JL Negrete 《Canadian Metallurgical Quarterly》1998,53(5):269-273
Therapeutic interventions in the skeletal system are an essential part of interventional radiology. Although in terms of figures these procedures are applied less frequently, they are very effective. Percutaneous transarterial embolization of a spinal tumor is well-established interventional treatment. It is primary treatment for preoperative devascularization, but also for palliation of pain and for reduction of tumor volume. As an alternative access for embolization, direct percutaneous puncture of a vertebra is used. A new and promising technique is vertebroplasty, the percutaneous injection of acrylic surgical cement in destroyed vertebrae. The present paper discusses indications, technique, results and complications of these interventional therapeutic modalities in the treatment of primary and secondary spinal tumors. 相似文献