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1.
After the USSR: Ethnicity, Nationalism, and Politics in the Commonwealth of Independent States. Anatoly M. Khazanov. Madison: University of Wisconsin Press, 1995. 311pp.
Who Gets the Past? Competition for Ancestors among Non-Russian Intellectuals in Russia. Victor A. Shnirelman. Washington, DC: Woodrow Wilson Center Press; Baltimore, MD: Johns Hopkins University Press, 1966. 98 pp.
In the Soviet House of Culture:. Century of Perestroikas. Bruce Grant. Princeton, NJ: Princeton University Press, 1995. 225 pp.  相似文献   

2.
Deletions in the argD, crp, cysG genes (73-74 min of the Escherichia coli genetic map) were obtained by heat induction of the phage lambda c1857 b221 rex::Tn5 integrated previously into the cysG gene by homologous recombination in the cysG::Tn5 mutant. Properties of the deletions obtained suggest the gene order: argD-crp-cysG.  相似文献   

3.
Paraglucocorticoid- and paramineralocorticoid-binding cytosolic receptors (pGR, pMR) were demonstrated in the intestine and kidney of the frog, Rana catesbeiana and in the intestine of the turtle, Chrysemys picta, in the presence of sodium molybdate. These receptors were of high affinity and low capacity with the following binding parameters: pGR:Kd:frog intestine (FI), triamcinolone acetonide (TA): 3.3 nM, corticosterone (B): 3.4 nM; frog kidney (FK), TA:4.3 nM, B: 9.3 nM; turtle intestine (TI), TA: 4.8 nM; Nmax: FI, TA: 357, B: 371; FK, TA: 301, B: 157; TI, TA: 350 fmol/mg protein. pMR:Kd: FI, aldosterone: 0.9 and 90 nM (biphasic curves); FK, aldosterone: 0.6 and 36 nM (biphasic curves); Nmax: FI, 13 and 147 fmol/mg protein; FK, 78 and 109 fmol/mg protein. The receptor had the following ligand affinities: pGR: FI and FK: triamcinolone acetonide greater than DOC greater than 11 beta-hydroxyprogesterone greater than progesterone greater than corticosterone greater than cortisol greater than aldosterone greater than 11-dehydrocorticosterone greater than 17 alpha-hydroxyprogesterone greater than cortisone; TI: triamcinolone acetonide greater than corticosterone greater than progesterone greater than DOC greater than cortisol greater than aldosterone; pMR: FI and FK: corticosterone greater than 11 beta-hydroxyprogesterone greater than aldosterone greater than triamcinoline acetonide = cortisol greater than DOC greater than 11-dehydrocorticosterone greater than progesterone greater than 17 alpha-hydroxyprogesterone greater than cortisone. Androgens, estrogens or 18-hydroxycorticosterone did not compete for binding in either tissue. The heat activated frog receptors did not bind to naked DNA, though the turtle receptor did. It was possible to show that cytosol receptor-ligand complexes from all tissues were bound by nuclear acceptor sites. On linear sucrose gradients, the FI TA-receptor complex sediments with a single peak (7.5S), the FK TA-receptor complex gave two peaks (8.0 and 4.4S) and the TI TA-receptor complex showed a single peak (9.0S). The hydrodynamic parameters of the pGR's were determined by gel exclusion on Sephacel S-300. The following results were obtained: Mr: FI, 265, 80, 40 kDa (multiple proteins); FK, 280, 60, 20 kDa (multiple proteins); TI, 366 kDa; Rs: FI, 6.9, 3.9 nm; FK, 6.9, 2.9 nm; TI, 7.6 nm; f/f0: FI, 1.6; FK, 1.6; TI, 1.6. It is suggested on the basis of the binding and hydrodynamic parameters that non-mammalian epithelia corticosterone receptors have undergone biochemical evolution from one class of vertebrates to another.  相似文献   

4.
The four major sulfolipids in the non-photosynthetic marine diatom, Nitzschia alba, were isolated in pure form and their structures were established spectrometrically and by identification of their hydrolysis products as (a) 24-methylene cholesterol sulfate, (b) 1-deoxyceramide-1-sulfonate, (c) phosphatidyl sulfocholine (a sulfonium analogue of phosphatidylcholine) and (d) sulfoquinovosyl diglyceride. The major characteristic fatty acids of the sulfolipids were: for the deoxyceramide sulfonate, 16 : 0 (26%) and 16 : 1-delta3-trans (64%); for the sulfonium analogue, 14 : 0 (30%), 18 : 1 (12%), 18 : 2 (8%), 20 : 5 (27%) and 22 : 6 (4%); and for the sulfoquinovosyl diglyceride (two species, respectively), 14 : 0 (9%, 22%), 16 : 0 (16%, 28%), 18 : 1 (8%, 22%), 20 : 5 (42%, 23%) and 22 : 6 (14%, 2%). Traces of lyso-derivatives of sulfoquinovosyl diglyceride and phosphatidyl sulfocholine were also detected. The deoxyceramide sulfonate and the phosphatidyl sulfocholine represent novel membrane lipid components not previously detected in other organisms. They may however have a widespread distribution in marine diatoms and perhaps in marine organisms generally.  相似文献   

5.
Changes in the carbohydrate content of the KB cell during the growth cycle   总被引:1,自引:0,他引:1  
KB cells were grown in suspension culture and synchronized with a double thymidine block. Cells were removed at various times during the cell cycle and analyzed for sialic acid, fucose, mannose and galactose. The mannose, galactose, and fucose contents of the cells all showed a decrease during the mitotic phase. The content of sialic acid decreased, but later in the cycle. When the cell was not dividing the molar rations of sialic acid to fucose: mannose: galactose were approximately 2:5:3 when sialic acid was expressed as 1; the ratios dropped to approximately 1:3:1.5 throughout division. These results indicate that the glycoprotein and/or glycolipid contents of KB cells probably change throughout the cell cycle.  相似文献   

6.
Two sunflower (Helianthus annuus L.) mutants with high concentrations of saturated fatty acids in their seed oil have been identified and studied extensively. The mutant line CAS-5 has high concentrations of palmitic acid (C16:0) (>25% compared with 7% in standard sunflower seed oil) and low-C18:0 values (3%). CAS-3 is characterized by its high levels of stearic acid (C18:0) (>22% compared with 4% in standard sunflower seed oil) and a low-C16:0 content (5%). CAS-5 also possesses elevated levels of palmitoleic acid (C16:1) (>5%), which is absent in standard sunflower seed oil. The objective of this study was to determine the relationships between the loci controlling the high-C16:0 and the high-C18:0 traits in these mutants. Plants of both mutants were reciprocally crossed. Gas chromatographic analyses of fatty acids from the seed oil of F1, F2, F3 and the BC1F1 to CAS-5 generations indicated that the loci controlling the high-C16:0 trait exerted an epistatic effect over the loci responsible for the high-C18:0 character. As a result, the phenotypic combination containing both the high-C16:0 levels of CAS-5 and the high-C18:0 levels of CAS-3 was not possible. However, phenotypes with a saturated fatty acid content of 44% (34.5% C16:0+9.5% C18:0) were identified in the F3 generation. These are the highest saturated (C16:0 and C18:0) levels reported so far in sunflower seed oil. When F3 C16:0 segregating generations in both a high- and a low-C18:0 background were compared, the high-C16:1 levels were not expressed as expected in the high-C18:0 background (CAS-3 background). In this case, the C16:1 content decreased to values below 1.5%, compared with >5% in a low-C18:0 background. As the stearoyl-ACP desaturase has been reported to catalyze the desaturation from C16:0-ACP to C16:1-ACP, these results suggested that a decrease in its activity was involved in the accumulation of C18:0 in the high-C18:0 mutant CAS-3. Received: 10 March 1999 / Accepted: 16 June 1999  相似文献   

7.
This essay looks at the historical significance of three APS classic papers that are freely available online: Cannon WB and de la Paz D. Emotional stimulation of adrenal secretion. Am J Physiol 28: 64-70, 1911 (http://ajplegacy.physiology.org/cgi/reprint/28/1/64). Cannon WB. The emergency function of the adrenal medulla in pain and the major emotions. Am J Physiol 33: 356-372, 1914 (http://ajplegacy.physiology.org/cgi/reprint/33/2/356). Cannon WB. Studies on the conditions of activity in endocrine glands. V. The isolated heart as an indicator of adrenal secretion induced by pain, asphyxia and excitement. Am J Physiol 50: 399-432, 1919 (http://ajplegacy.physiology.org/cgi/reprint/50/3/399).  相似文献   

8.
1. Although single cones and double cones in the chicken retina had been documented for more than 30 years, the exact morphology of these cells had never been studied by the scanning electronmicroscopy. In this brief report, we present the evidence for the first time the existence of two types of single cones and three types of double cones (termed as types A, B, and C), each with distinct morphology.2. The proportion of type A:type B:type C double cones, as estimated from the midperipheral and central regions of our scanning specimens, was about 30%:50%:20%.3. Based on the literature data that red oil droplets reside in single cones and yellow oil droplets in chief cones of the double cones, the proportion of single to double cones was deciphered and the relative proportion was estimated to be 1:0.91 in the central region, 1:0.92 in the midperiphery, and 1:0.84 in the periphery.  相似文献   

9.

From the Heart of the WorldThe Elder Brothers’ Warning. Director: Alan Ereira; camera: Bill Broomfield; editor: Horacio Queiro; sound: John Wills. 1990, color, 87minutes VHS‐NTSC, VHS‐PAL. English narration and subtitles. Distributed by BBC Enterprises, 80 Wood Lane, London W12 OTT; or Mystic Fire Video, 225 Lafayette Street, Suite 1206, New York 10012; sale only, £12 or $29.95 + $4.00 postage. Ereira, Alan, The Heart of the World. London: Jonathan Cape, 1990, bibliography, index, 288 pp., £15.99.  相似文献   

10.
<正>活动节律和活动时间分配是动物行为学研究的两个重要方面,它们直接与动物的代谢和能量收支相关,但它们又会随环境不同不断调整。通过比较不同生态条件下动物的活动节律和活动时间分配,  相似文献   

11.
The green sulfur photosynthetic bacterium Chlorobaculum (Cba.) tepidum (previously known as Chlorobium tepidum), which grows at an optimal temperature of around 45 °C, biosynthesized unique disaccharide rhamnosylgalactosyldiacylglyceride (RGDG) having a methylene-bridged palmitoleyl (17:Cyc) and a palmitoyl group (16:0) as the two acyl chains in a molecule [RGDG(17:Cyc,16:0)], together with the corresponding monosaccharide monogalactosyldiacylglyceride (MGDG). Here, we report changes in the structure and composition of the glycolipids that are dependent upon the temperature and period of cultivation. With a decrease in temperature to 25 °C, the two major glycolipids were almost completely eliminated, and MGDG with a palmitoleyl (16:1) and a (16:0) group concomitantly became the major glycolipid. MGDG(16:1,16:0) corresponded to the removal of an α-rhamnosyl and a cyclopropyl methylene group from RGDG(17:Cyc,16:0) and the lack of the CH(2) group in MGDG(17:Cyc,16:0). The structural conversion was almost reversible when the Cba. tepidum adapted to low and high temperatures was cultured again at 45 and 25 °C, respectively. Moreover, during this cultivation, the structure and composition of glycolipids were sequentially changed: MGDG(16:1,16:0), MGDG(17:Cyc,16:0), and RGDG(17:Cyc,16:0) predominated in the exponential, stationary and late phases of the cultivation, respectively. On the basis of these time-dependent changes, the unique disaccharide RGDG(17:Cyc,16:0) was thought to be created by the site-specific transfer of an α-rhamnosyl group to MGDG(17:Cyc,16:0) after insertion of a methylene group into the precursor MGDG(16:1,16:0). These culturing temperature- and time-dependent changes in glycolipids at the molecular level allow us to discuss their biosynthesis as well as physiological function in green photosynthetic bacteria.  相似文献   

12.
The cloning and nucleotide sequence of the genes (idi, crtE, crtYB, crtl and crtS) controlling the astaxanthin biosynthesis pathway of the wild-type ATCC 24230 strain of Xanthophyllomyces dendrorhous in their genomic and cDNA version were obtained. The idi, crtE, crtYB, crtl and crtS genes were cloned, as fragments of 10.9, 11.5, 15.8, 5.9 and 4 kb respectively. The nucleotide sequence data analysis indicates that the idi, crtE, crtYB, crtl and crtS genes have 4, 8,4, 11, and 17 introns and 5, 9, 5, 12 and 18 exons respectively. In addition, a highly efficient site-directed mutagenesis system was developed by transformation by integration, followed by mitotic recombination (the double recombinant method). Heterozygote idi (idi+/idi-::hph), crtE (crtE+/crtE-::hph), crtYB (crtYB+/crtYB-::hph), crtI (crtI+/crtI-::hph) and crtS (crtS+/crtS-::hph) and homozygote mutants crtYB (crtYB-::hph/crtYB-::hph), crtI (crtI-::hph/crtI-::hph) and crtS (crtS-::hph/crtS-::hph) were constructed. All the heterozygote mutants have a pale phenotype and produce less carotenoids than the wild-type strain. The genetic analysis of the crtYB, crtl and crtS loci in the wild-type, heterozygote, and homozygote give evidence of the diploid constitution of ATCC 24230 strains. In addition, the cloning of a truncated form of the crtYB that lacks 153 amino acids of the N-terminal region derived from alternatively spliced mRNA was obtained. Their heterologous expression in Escherichia coli carrying the carotenogenic cluster of Erwinia uredovora result in trans-complementation and give evidence of its functionality in this bacterium, maintaining its phytoene synthase activity but not the lycopene cyclase activity.  相似文献   

13.
A method for the analysis of spatial pattern using quadrats of different sizes is developed on the basis of the relationship of mean crowding () to mean density (m). The -on-m regression obtained by successive changes in quadrat size in a single population (unit-size relation) shows a characteristic pattern according to the type of distribution. By aid of the ρ-index proposed here, we can distinguish the random, aggregated and uniform distributions of the basic components (individual or group of individuals). The ρ serves as an index of spatial correlation between neighbouring quadrats, and it also provides information on the approximate area occupied by clump (colony), distribution pattern of individuals within clumps, and possibly the distribution pattern of clumps themselves. Even in a specified type of distribution, the unit-size relation is not necessarily identical with the relation for a series of populations at a particular quadrat size (series relation). The changes in the series relationship with successive changes of quadrat sizes are also considered for some basic patterns of distributions. The combined use of the unit-size and the series relations for a set of populations of the species under study may provide a satisfactory picture of the spatial pattern characteristic of the species. Application of the method is illustrated by using distribution data of several species of animals and plants. The advantage of the present method over other methods are discussed, and the formulae for determining the optimum quadrat unit in sampling surveys are given.  相似文献   

14.
The rates of 3H-norepinephrine (3H-NE) uptake into isolated nuclei-free homogenates from diencephalon were examined in freely cycling female rats of all phases of the estrous cycle. Four time points were investigated in each phase: 12:00, 14:00, 16:00 and 18:00 h. The proestrus and estrus animals displayed no change in uptake rates across the four time points. However, the metestrus and diestrus groups were found to undergo hour to hour variations in uptake rates. In the diestrus group, a significant rise in uptake of 22% was observed from 12:00 to 16:00 h. This increase was followed by a decrease of 21% by 18:00 h as compared to 16:00 h levels. Similarly, a slight increase in uptake was observed in the metustrus animals from 12:00 to 16:00 h. At 18:00 h a 40% decrease from the 16:00 h value was observed. An average of the mean levels of uptake of all phases was calculated for each time point. At 16:00 h an increase in the mean uptake of about 20% was observed when compared to either the 12:00 or the 18:00 h values. Since transmitter reuotake is the major means of terminating receptor activation or inhibition, it is suggested that the above variations in NE uptake may modulate synaptic activity and play a role in the regulation of behavioral and physiological aspects of the estrous cycle.  相似文献   

15.
The molecular heterogeneity of platelet-activating factor (PAF) synthesized by unstimulated and Ca2+ ionophore (A23187)-stimulated PMN from rat, mouse, and guinea pig and by rat basophilic leukemia (RBL) cells was investigated by gas chromatography-negative ion chemical ionization mass spectrometry. Several molecular species of PAF ranging from C14:0 to C19:0 were detected in all of the cells studied. PAF produced by each cell type exhibited a unique pattern of molecular species distribution. Although C16:0 was the major PAF molecular species of rat PMN and RBL cells representing 96% and 85% of the total PAF, respectively, PAF from mice PMN contained 81% of C16:0, 10% of C18:1, and 6% of C18:0. Alternatively, A23187-stimulated guinea pig PMN yielded PAF molecular species 35% in C16:0, 35% in C17:0, 8% in C18:1, and 3% in C18:0. Small but significant differences in the PAF molecular species distribution of resting and ionophore stimulated cells were also observed. In contrast to the PAF molecular species composition, the precursor 1-O-alkyl-2-acyl-glycero-3-phosphocholine of all the cell types was predominantly hexadecyl (C16:0) alkyl chain in the sn-1 position, representing 60 to 80% of the total 1-O-alkyl-2-acyl-glycero-3-phosphocholine. Thus, these results not only indicate a high degree of selectivity for utilization of precursor substrates for PAF biosynthesis, but also demonstrate that the selectivity is species specific.  相似文献   

16.
We describe the otolith assemblage from the early Miocene (Burdigalian) exposures of the Castillo Formation at the Cerro La Cruz locality (Falcón Basin, Lara State, northwestern Venezuela). The samples were obtained through surface and bulk sampling at distinct stratigraphic levels of the study area. The otolith assemblage from Cerro La Cruz includes 14 families, 25 genera and 30 taxa, of which 20 are reported for first time from the Castillo Formation. These include two new sciaenid taxa, Ctenosciaena angusticaudata nov. sp. and Pareques laraensis nov. sp. The Castillo Formation otolith assemblage represent fishes typical of shallow and near-shore and coral reef associated environments as characterized primarily by a high taxonomic diversity and abundance of Sciaenidae, and the lack of mesopelagic families (Myctophidae). The faunal composition of Cerro La Cruz is similar to other chronological equivalent sedimentary units along the proto-Caribbean area (Pirabas and Cantaure formations; Brazil and Venezuela respectively), though the Castillo Formation fish fauna shows lower taxonomic diversity, suggesting some heterogeneity of the coastal and near shore marine environments along the southern portion of the proto-Caribbean.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:B79F51B8-BC35-4119-8957-84544286868D  相似文献   


17.
Capsule: There were up to 6348 Ring Ouzel territories in the UK in 2012.

Aims: To produce estimates of the size of the Ring Ouzel breeding population in the UK and its constituent countries.

Methods: A stratified random selection of tetrads was surveyed within the known breeding range, except for the remaining breeding areas on Dartmoor and historical sites elsewhere, which were surveyed in their entirety. The methods followed those devised for the first UK-wide survey in 1999, using playback of song at specific points along tetrad transect lines.

Results: The UK population estimate in 2012 was 5332 (95% confidence limits (CL), 4096–6875) territories, a non-significant decline of 29% since 1999. There were no significant differences in the population changes in England, Scotland and Wales between the two surveys. An estimation of survey efficiency found that 84% of territories were located by the national survey methods, suggesting that the UK population in 2012 could have been as many as 6348 (95% CL, 4825–8198) territories.

Conclusion: The results suggest that the UK Ring Ouzel population has continued to decline since 1999. Ongoing and future research should determine where the main threats to the population are: on the breeding or wintering grounds, or during migration.  相似文献   


18.
Extraordinary Bodies: Figuring Physical Disability in American Culture and Literature. Rosemarie Garland Thomson. New York: Columbia University Press, 1997. 200 pp.
Freakery: Cultural Spectacles of the Extraordinary Body. Rosemarie Garland Thomson. ed. New York: New York University Press, 1996. 400 pp.
Monster Theory: Reading Culture. Jeffrey Jerome Cohen. ed. Minneapolis: University of Minnesota Press, 1996.315pp.  相似文献   

19.
ABSTRACT Nineta pallida (Schneider) (Neuroptera: Chrysopidae) larvae were reared at 21CC under various stationary photoperiods. The duration of the first stadium varied with daylength. Long-day regimes (LD 18:6 and 16:8 h) induced the fastest development, whereas the first ecdysis was more or less delayed in LD 14:10 and 13:11 h. Medium days (LD 12:12 h) resulted in the longest duration of the first stadium and high mortality, and all shorter days (LD 10:14, 8:16 and 6:18 h) in a moderate delay in the first ecdysis in all individuals. The facultative delay in development is thought to be a diapause, and viewed as a factor contributing to the annual synchronization of the life cycle.  相似文献   

20.
The levels of prostaglandins (PGs) were measured by radioimmunoassay in the interimplantation and the implantation sites as well as in the implantation site without the blastocyst in the rabbit on day 7 of pregnancy (168h post coitum). The concentrations of PGs were also determined in the blastocyst (PGF:101.59+?4.33 and PGE-A:29.74+?3.11 ng/blastocyst, n=6) and the blastocel fluid (PGF:253.55+?39.56 and PGE-A:83.29+?6.60 ng/100 ul, n-4) on day 7. The levels of both PGF and PGE-A were significantly higher in the implantation site as compared to interimplantation site (PGF:73.63±6.68 vs. 0.59±0.21 and PGE-A:25.52±3.30 vs. 1.22±0.18 ng/100 mg wet weight n=8). The removal of the blastocyst from the implantation site drastically reduced the concentrations of PGs in this site (PGF:8.71±2.80 and PGE-A:1.64±0.12 ng/100 mg wet weight, n=8). The results provide evidence that the blastocyst is the major source of PGs which contribute to the hige concentration in the implantation site in the rabbit.  相似文献   

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