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881.
882.
Markusova Valentina Minin Valdimir Libkind Alexandr Arapov Michael 《Scientometrics》2001,50(3):541-551
This paper describes results of a survey conducted among the Russian Foundation for Basic Research (RFBR) grant-holders. The
aim of this paper is to examine the attitude of grant holders to new multi-channel funding system and to assess its significance
for Russian scientists involved in research in natural and applied sciences. It is a first attempt to get a fair and general
picture of what scientists think about competitive funding. In 1999, 1440 questionnaires were distributed by mail. The response
rate was 31.8%. The results of the survey clearly show that proposal writing has become a substantial part of research activity
in Russia. Each respondent received more than 5 grants during 1993-1997. The RFBR and foreign funding agencies, particularly
ISF, INTAS, and the Civilian Research and Development Foundation equally evaluated Russian scientists' performance: about
69.% of RFBR grant-holders were awarded a grant from foreign agencies. The present findings are being used, as a practical
matter, to guide and inform the Ministry of Science and Technology Policy which is responsible for the promotion R in Russia
to organize a special training for students and post docs on proposal writing.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
883.
884.
AL Muliukin KA Lusta MN Griaznova AN Kozlova MV Duzha VI Duda GI El'-Registan 《Canadian Metallurgical Quarterly》1996,65(6):782-789
Under certain cultivation conditions, the bacteria Bacillus cereus and Micrococcus luteus form cystlike refractive cells (up to 60% of the total number) that retain viability over a long time, are metabolically inactive and thermotolerant and possess specific ultrastructure. These properties allow them to be attributed to a new type of resting forms of microorganisms. 相似文献
885.
886.
A patient is described, who was examined 1 year after surgery for mandibular cyst diagnosed as radicular near the !5 tooth and for plasty of the secondary osseous cavity with hydroxyapatite granulate. X-Ray examination revealed a cystic cavity near the roots of teeth !234. Histologic examination of tissue fragments and the remainder of hydroxyapatite granulate, obtained by cystectomy, helped diagnose a primordial cyst. Intensive bone regeneration was observed at the site of hydroxyapatite granule accumulation and fusion of the new bone with the granules to form a solid osseogranular complex. The authors recommend hydroxyapatite ceramic granules for surgical treatment of minor and medium bone defects and for corrective bone plasty. 相似文献
887.
LB Son AP Kaplun AA Spilevski? IuE Andiia-Pravdivy? SG Alekseeva VB Gribor'ev VI Shvets 《Canadian Metallurgical Quarterly》1998,24(10):787-793
A method for betulinic acid synthesis from betulin was developed. Betulin was oxidized with chromium oxide (VI) into betulonic acid, which was reduced with sodium borohydride to yield a mixture of 3-hydroxy epimers containing 85% of the natural beta-epimer. Studying changes in light scattering by dispersions of liposomes with different contents of betulinic acid revealed that up to 10 mol % of this compound may be entrapped in liposomes. The dependence of the efficiency of the betulinic acid entrapment on liposome composition was studied. The presence of polyvinylpyrrolidone or Proxanol increased the resistance of betulinic acid-containing liposomes to aggregation. These polymers solubilized betulinic acid with the same efficiency as liposomes. 相似文献
888.
VI Bystritskii 《Canadian Metallurgical Quarterly》1996,112(4):28-30
By an unsophisticated experiment, published data on the anatomy of the eye, wave theory of light, and the laws of geometrical optics the author tries to prove that a spherical concave screen is the optimal variant of a screen on which spherical wave front is projected, formed by a single lens. The shape of the wave front and of the concave screen are in complete agreement. Such optical imperfections as the field curvature, distortion, coma (partially), and astigmatism of the oblique light beams are compensated for. These optical drawbacks are undetectable on a concave screen, and hence they are proposed to be the shortcomings of a flat screen. The author compares this to a spherical shape of the eye, the posterior wall of which represents a concave screen, an indisputable fact, and assumes that the before-named optic imperfections are completely compensated for in human eye due to concavity of the posterior optic wall. Based on the anatomy and practical results of using aspherical refracting surfaces in artificial optic devices, the author draws a parallel with the anatomical structures of the eye possessing aspherical refracting surfaces in order to demonstrate that higher and lower-order spherical aberrations (Zeidel's aberrations) are fully compensated for in human eye, as are the position and enlargement chromatism. Analysis of published data permitted the author to assert that the eye of man is characterized by a method for compensation of spherical aberrations, which has no analogs in man-made practice. Hence, the Nature has imparted the eye with such a collection of compact, universal, and highly effective methods for compensation of optic imperfections, which is not to be found in any of the man-made devices of today. 相似文献
889.
VS Baranov T Ivaschenko B Bakay M Aseev R Belotserkovskaya H Baranova P Malet J Perriot P Mouraire VN Baskakov GA Savitskyi S Gorbushin SI Deyneka E Michnin A Barchuck V Vakharlovsky G Pavlov VI Shilko T Guembitzkaya L Kovaleva 《Canadian Metallurgical Quarterly》1996,97(4):516-520
A homozygous gene deletion at the glutathione S-transferase M1 (GSTM1) locus of genomic DNA from blood spots was studied by PCR in the group of Slavic populations from the north-western and central-eastern regions of European Russia and in patients with lung cancer (LC), other tumors (OT), endometriosis (E), alcoholic cirrhosis (AC), cystic fibrosis (CF) and chronic bronchitis (CB). The frequencies of the GSTM1 0/0 genotype were 38.8% and 67.5% for both population groups, respectively. The proportion of the GSTM1 gene deletion genotype was estimated as significantly increased in LC (81%), OT (65%), E (81%), AC (77.3%), and in CB (73.6%) patients with symptoms of CB confirmed by X-ray but not in CB patients without X-ray evidence of disease (40.9%). A definite preponderance of GSTM1-0 homozygotes (51.1%) has been registered in CF patients of the pancreatic sufficient group with clear-cut pulmonological manifestations but not in those of the pancreatic insufficient group with predominantly intestinal or mixed clinical symptoms (41.2% and 37.5%, respectively). Earlier clinical manifestations and death before the age of 5 years are typical for GSTM1-deleted CF patients. These data support the notion that GSTM1 deletion should be considered as a convenient genetic marker for the early detection of groups at higher risk of many diseases caused by environmental and genetic factors, where manifestation depends on the lack of detoxification. High levels of GSTM1 0/0 genotypes in E patients favor the substantial contribution of certain environmental toxins in the pathogenesis of this widespread disease. 相似文献
890.