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21.
Genetic diversity of seven Rhus L. species was assessed using random amplified polymorphic DNA (RAPDs) markers. Initially, 90 primers were screened, of which 25 produced reproducible amplification products. These primers generated a total of 296 bands, with an average of 11.8 bands per primer. Out of 296 bands scored, 236 (80%) were polymorphic and 62 (20%) were monomorphic. Primers OPC-05 and OPD-05 generated 100% polymorphic bands. The resolving power of primers ranged from 9.4 to 26.8. Similarity matrix values ranged from 0.45 to 0.63. The dendrogram generated using Unweighted Pair Group Method using Arithmetic Averages (UPGMA) grouped all the species of Rhus in one major group with two sister groups, whilst R. pyroides Burch. and R. dentata Thunb. were outliers. R. gerrardii (Harv. ex Engl.) Diels, R. glauca Thunb. and R. pentheri Zahlbr. constituted one sister group, while R. natalensis Bernh. ex C. Krauss and R. gueinzii Sond. were included in the other. The degree of genetic diversity observed between seven species of Rhus with RAPD markers suggest that this approach could be used for studying the phylogeny of the genus. 相似文献
22.
McPherson JP Lemmers B Chahwan R Pamidi A Migon E Matysiak-Zablocki E Moynahan ME Essers J Hanada K Poonepalli A Sanchez-Sweatman O Khokha R Kanaar R Jasin M Hande MP Hakem R 《Science (New York, N.Y.)》2004,304(5678):1822-1826
Mus81-Eme1 endonuclease has been implicated in the rescue of stalled replication forks and the resolution of meiotic recombination intermediates in yeast. We used gene targeting to study the physiological requirements of Mus81 in mammals. Mus81-/- mice are viable and fertile, which indicates that mammalian Mus81 is not essential for recombination processes associated with meiosis. Mus81-deficient mice and cells were hypersensitive to the DNA cross-linking agent mitomycin C but not to gamma-irradiation. Remarkably, both homozygous Mus81-/- and heterozygous Mus81+/- mice exhibited a similar susceptibility to spontaneous chromosomal damage and a profound and equivalent predisposition to lymphomas and other cancers. These studies demonstrate a critical role for the proper biallelic expression of the mammalian Mus81 in the maintenance of genomic integrity and tumor suppression. 相似文献
23.
Tumor suppression with a combination of alpha-difluoromethyl ornithine and interferon 总被引:1,自引:0,他引:1
alpha-Difluoromethyl ornithine and mouse type 1 interferon, when administered simultaneously, were highly toxic to B16 melanoma cells in culture. Oral administration of alpha-difluoromethyl ornithine suppressed B16 melanoma development in mice 85 percent whereas interferon given subcutaneously inhibited tumor growth only 24 percent. Total or near total suppression of tumor growth was observed in mice receiving both treatments. 相似文献
24.
We demonstrate universal computation in an all-fluidic two-phase microfluidic system. Nonlinearity is introduced into an otherwise linear, reversible, low-Reynolds number flow via bubble-to-bubble hydrodynamic interactions. A bubble traveling in a channel represents a bit, providing us with the capability to simultaneously transport materials and perform logical control operations. We demonstrate bubble logic AND/OR/NOT gates, a toggle flip-flop, a ripple counter, timing restoration, a ring oscillator, and an electro-bubble modulator. These show the nonlinearity, gain, bistability, synchronization, cascadability, feedback, and programmability required for scalable universal computation. With increasing complexity in large-scale microfluidic processors, bubble logic provides an on-chip process control mechanism integrating chemistry and computation. 相似文献
25.
Neutron stars are some of the densest manifestations of massive objects in the universe. They are ideal astrophysical laboratories for testing theories of dense matter physics and provide connections among nuclear physics, particle physics, and astrophysics. Neutron stars may exhibit conditions and phenomena not observed elsewhere, such as hyperon-dominated matter, deconfined quark matter, superfluidity and superconductivity with critical temperatures near 10(10) kelvin, opaqueness to neutrinos, and magnetic fields in excess of 10(13) Gauss. Here, we describe the formation, structure, internal composition, and evolution of neutron stars. Observations that include studies of pulsars in binary systems, thermal emission from isolated neutron stars, glitches from pulsars, and quasi-periodic oscillations from accreting neutron stars provide information about neutron star masses, radii, temperatures, ages, and internal compositions. 相似文献
26.
S. Kundu Ranjan Bhattacharyya Ved Prakash B.N. Ghosh H.S. Gupta 《Soil & Tillage Research》2007,92(1-2):87-95
Soil organic matter (SOM) contributes to the productivity and physical properties of soils. Although crop productivity is sustained mainly through the application of organic manure in the Indian Himalayas, no information is available on the effects of long-term manure addition along with mineral fertilizers on C sequestration and the contribution of total C input towards soil organic C (SOC) storage. We analyzed results of a long-term experiment, initiated in 1973 on a sandy loam soil under rainfed conditions to determine the influence of different combinations of NPK fertilizer and fertilizer + farmyard manure (FYM) at 10 Mg ha−1 on SOC content and its changes in the 0–45 cm soil depth. Concentration of SOC increased 40 and 70% in the NPK + FYM-treated plots as compared to NPK (43.1 Mg C ha−1) and unfertilized control plots (35.5 Mg C ha−1), respectively. Average annual contribution of C input from soybean (Glycine max (L.) Merr.) was 29% and that from wheat (Triticum aestivum L. Emend. Flori and Paol) was 24% of the harvestable above-ground biomass yield. Annual gross C input and annual rate of total SOC enrichment were 4852 and 900 kg C ha−1, respectively, for the plots under NPK + FYM. It was estimated that 19% of the gross C input contributed towards the increase in SOC content. C loss from native SOM during 30 years averaged 61 kg C ha−1 yr−1. The estimated quantity of biomass C required to maintain equilibrium SOM content was 321 kg ha−1 yr−1. The total annual C input by the soybean–wheat rotation in the plots under unfertilized control was 890 kg ha−1 yr−1. Thus, increase in SOC concentration under long-term (30 years) rainfed soybean–wheat cropping was due to the fact that annual C input by the system was higher than the required amount to maintaining equilibrium SOM content. 相似文献
27.
Four-week old plants of pepper (Capsicum annuum L.) cultivar ‘Jawala’ were sprayed with an aqueous solution of chlorflurenol at concentrations of 50, 100, 150 or 200 mg/l. Chlorflurenol reduced the growth of the main shoot and the area of the leaf, weakened apical dominance, increased the growth and number of lateral branches, and reduced the growth and number of stamens. Induction of stamenless (pistillate) flowers was an interesting effect. The size, viability and germination of pollen grains were reduced by chlorflurenol. It caused an appreciable promotion in fruit-set up to a concentration of 150 mg/l and a drastic reduction at 200 mg/l, accompanied by increase and decrease of yield, respectively. Parthenocarpy was observed at 100, 150 and 200 mg/l. 相似文献
28.
29.
P Prakash 《The Indian veterinary journal》1969,46(6):493-497
30.
For studying the effect of dietary supplementation of guduchi (Tinospora cordifolia) peripartum on lactation an investigation was conducted on 15 pregnant Karan Fries crossbred cows which were divided into two groups: treatment group of eight cows which were supplemented with guduchi at 60 g/day for 45 days prepartum and 120 g/day for 45 days postpartum; control group of seven pregnant cows which were not supplemented with guduchi. Jugular blood samples were collected from all cows during the periparturient period for analysis of various blood cell and plasma parameters. A significantly higher total leukocyte count, lymphocyte count, neutrophil count and neutrophil/lymphocyte ratio was recorded in the guduchi supplemented treatment group in comparison to untreated control cows throughout the experimental period. The increase of milk production over 305 days of lactation due to guduchi supplementation was significant (p < 0.05). A significant (p < 0.05) reduction in somatic cell count was also observed during the experimental period. Milk composition (fat, protein, lactose and SNF) was similar (p > 0.05) for both the groups. Plasma non esterified fatty acid (NEFA) concentrations were significantly higher (p < 0.01) in cows supplemented with guduchi throughout the course of study. Plasma concentration of growth hormone in the treated cows was also significantly higher beginning on the day of parturition up to 3 weeks postpartum (p < 0.05) in comparison to unsupplemented group. 相似文献