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991.
992.
The climbing habit has evolved independently in many plant taxa, offering vines the ability to compete with non-climbing vegetation
for resources such as light, nutrients, and water. This review examines the structural and functional characteristics that
allow climbing plants to (1) achieve widespread dispersal, (2) transport large amounts of water throughout vessels, (3) maintain
high photosynthesis levels through a large leaf area to biomass ratio, (4) achieve rapid vertical and horizontal expansion
by fast growth rates and various climbing mechanisms and (5) survive and recover from disturbances. Due to the competitive
effects of vines on trees, management of vine growth is used to preserve tropical timber plantations, combat invasive weeds,
and promote rainforest recovery. In order to sustainably manage the vines into the future, it is necessary to understand the
mechanisms by which they can alter tropical forest succession and the impacts of various management techniques. 相似文献
993.
994.
Zh T A?tbaeva P N Deriabin B V Karal'nik K G Kaverina 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1989,(5):16-20
Highly sensitive and specific erythrocyte diagnostic agents (ED) for the determination of antibodies to Proteus O-antigens have been obtained by the sensitization of formolated sheep red blood cells (SPBC) with activated lipopolysaccharides (LPS) without the use of mediators. The tannin treatment of formolated SRBC and/or the increase of temperature from 45 degrees C to 100 degrees C in the process of the preparation of ED have been found to produce no increase in effectiveness. Antibody ED permitting the detection of Proteus O- and H-antigens has been obtained by the sensitization of formolated chick red blood cells with immunoglobulin preparations to Proteus hydroxylamine antigens, carried out with the use of amidol. The experiments have shown the possibility of using this antibody ED for the determination of O-antibodies in the antigen neutralization test with nonactivated LPS used as an agglutinating agent. The passive hemagglutination test with antibody ED has proved to be a more sensitive method for the detection of O-antibodies than the antigen neutralization test with antigenic ED. The determination of Proteus etiology in the passive hemagglutination test with the use of antigenic ED has been shown to be highly effective in the examination of patients with chronic osteomyelitis at the stage of exacerbation. 相似文献
995.
S V Revenko V V Ermishkin L Ia Selektor 《Biulleten' eksperimental'no? biologii i meditsiny》1989,107(4):395-396
Direct electric current of 3 microA applied through platinum electrode during 10 s to a fine strand teased mechanically from saphenous nerve, inhibits selectively C-fibre spikes in the strand and does not inhibit A-fiber spikes. The selective inhibition of C-fibers spikes in a fine strand is proposed as a method to identify a type of a single nerve fiber. 相似文献
996.
Multiple aligned sequence editor (MASE) 总被引:24,自引:0,他引:24
997.
Phenylalanine hydroxylase (PH) activity was discovered in the liver of 7-12 week old human embryos. Embryonic and adult PHs were identical, as shown by immunoelectrophoresis. Unlike the adult liver PH, the PH content of the extract of cytoplasmic proteins of embryonic liver was reduced but the specific activity was increased more than by one order of magnitude. H (57,000 D) and L (55,000 D) subunits were detected by immunoblotting. The L subunit predominates in the extract of membrane proteins of embryonic liver. Hence, the major part of phenylalanine oxidizing activity in the embryonic liver is related to the enzyme immunochemically identical with the PH of adult liver but differing from it in some structural and functional properties. 相似文献
998.
Immunoperoxidase labeling of fibronectin in one-day-old mouse first lower molars allowed to visualize a striking redistribution of this glycoprotein during terminal cytodifferentiation of odontoblasts. The modifications involved both extracellular and cell surface localizations. The possible roles of these modifications in terminal differentiation of odontoblasts are discussed. 相似文献
999.
V V Vlodavets I I Kolker G M Trukhina N S Bolovacheva T I Grafova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1980,(4):97-100
The possibility of detecting Pseudomonas aeruginosa and other Gram-negative bacteria in the air of the burn department at the Institute of Surgery was studied. The investigation of large volumes of air (0.5-1 m3) in the wards and the corridor with the use of a new bacteriological aerosol sampler, model IIAB-5, resulted in the detection of Pseudomonas aeruginosa. Besides, in a number of other rooms Klebsiella, Proteus, Citrobacter and Enterobacter were detected in the air. The possibility of the spread of Gram-negative opportunistic bacteria through the air in hospital conditions is discussed. 相似文献
1000.
Previous studies by us and others established that cell-cell adhesion is mediated by specific carbohydrate-to-carbohydrate
interaction (CCI). Those previous studies were based on various biochemical and biophysical approaches, including the use
of labeled glycosyl epitopes with fluorescent tag. However, these methods ideally require that the glycosyl epitope must be
fixed to a solid phase molecule, preferably with multivalency. The purpose of the present study is to establish a CCI process
using specific glycosyl residues conjugated to biotinylated diaminopyridine (BAP), and to observe: (i) clear occurrence of
homotypic CCI between “Os Fr.B” having 5–6 GlcNAc termini, vs. absence of such homotypic CCI between “Os Fr.1” having 2 GlcNAc termini; (ii) occurrence of heterotypic CCI between GM3
ganglioside and Os Fr.B, vs. absence of such heterotypic CCI between GM3 and Os Fr.1. Interaction between Os Fr.B-BAP conjugate and Os Fr.B-ceramide
mimetic (Os Fr.B-mCer) was demonstrated based on two experiments: (i) dose-dependent binding of Os Fr.B-BAP conjugate to polystyrene
plates coated with Os Fr.B-mCer was observed in the presence of bivalent cation, a prerequisite for all CCI processes, and
such binding was abolished by EDTA; (ii) binding between equal nanomolar Os Fr.B-BAP and Os Fr.B-mCer was inhibited by mM
concentration Os Fr.B without conjugate, in dose-dependent manner. Thus, cell adhesion processes based on homotypic CCI between
N-linked glycans having multiple GlcNAc termini, and heterotypic CCI between GM3 and such glycans, were clearly observed using
BAP conjugates of glycosyl epitopes. 相似文献