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1.
Candida lipolytica (strain ATCC 8662) was grown on a simple defined medium with n-hexadecane as the main carbon Source under batch fermentation conditions. The relative importance of the cells growing in the aqueous phase on the overall kinetics was studied. The effect of interfacial tension, unoccupied interfacial area, and pseudosolubility on the specific growth was also studied. Results are presented and discussed here. 相似文献
2.
Douglas W. Hoffman Richard A. Altschuler Joanne Gutierrez 《Journal of neurochemistry》1983,41(6):1641-1647
Abstract: The combined techniques of HPLC and radioimmunoassay were used to identify and quantitate enkephalin-related peptides in the guinea pig hippocampus. Both met- and leu-enkephalin were identified, in approximately a 2:1 ratio, as well as a third enkephalin-like molecule that is neither met- nor leu-enkephalin. The third enkephalin elutes earlier than met- or leu-enkephalin from a reversed-phase column, has a molecular weight similar to the other enkephalins, and is as active as these enkephalins are in inhibiting binding of labeled opiates to rat brain membranes. All regions of the hippocampus (dentate gyrus, CA1–2, CA3–4, and subiculum) contain all three immunoreactive peptides. Immunocytochemical techniques, using antisera raised against met-enkephalin, show with one antiserum immunoreactivity in the granule cell-mossy fiber system, and with the other scattered immunoreactive cells mostly in the CA2 region. Enkephalins are not confined to the mossy fiber system, as previously suggested, but may be a component of another hippocampal innervation. 相似文献
3.
The rumen ciliate Epidinium ecaudatum was cultured for 6 months in the presence of two strains of bacteria, starch, alfalfa, linseed oil meal, and buffered saline. The cultures required daily transfer and addition of fresh substrate. The protozoan degraded starch, soybean oil meal, linseed oil meal, and cottonseed oil meal, and the fermentation end products from the breakdown of starch were acetic and butyric acids with traces of formic, propionic, and lactic acids, carbon dioxide, and hydrogen. The relationship of E. ecaudatum to other species of rumen oligotrichs and bacteria is discussed. 相似文献
4.
Macrothrix mexicanus sp. nov. is described from central México, a transition zone between the nearctic and neotropics. All localities where it was found are over 1800 meters above sea level. It shows many resemblances with M. laticornis, M. camjatae and M. rosea but is characterized by a persistent dorsal tooth on the valve keel, a spinous papilla on the basipodite of the antenna, the second thoracic limb with a long conical sensillum between scraper 1 and the gnathobase, the endopod of trunk limb IV having two setae; the postabdomen with the dorsal margin bilobed, and the distal segment of the seta natatoria which is unusually long.Abbreviations used on figures EN
Endopodite
- EP
Epipodite
- EX
Exopodite
- IDL
Inner distal lobe
- ODL
Outer distal lobe
- GT
Gnatobase
- E1
Endite 1
- E2
Endite 2
- E3
Endite 3 相似文献
5.
J. F. Romero Collazos M. D. Marrodán E. Gutierrez Redomero 《International Journal of Anthropology》1996,11(1):11-19
Anthropometric characteristics of proportionality, body composition and somatotype have been determined in a group of 72 Spanish
judoists. The sample includes the junior male and female National Team, and seniors competitors in the last Olimpic Games
held in 1992, and participants in the National Championship of 1993. The methodology has been used according to Weiner and
Lourie(1981)and MOGAP procedures described by Borms et al. (1979). The obtained results show a similar proportionality profile
and mesoendomorphic mean somatotype in both male and female series. However, were found significant differences between sexes
as well as depending of weight categories. 相似文献
6.
Alfonso Pompella Caterina Cambiaggi Silvia Dominici Aldo Paolicchi Roberto Tongiani Mario Comporti 《Histochemistry and cell biology》1996,105(3):173-178
Confocal laser scanning fluorescence microscopy coupled to image analysis was employed in order to develop and evaluate procedures for the appraisal at the single-cell level of: (1) protein-bound 4-hydroxynonenal, the specific product of membrane peroxidation (by means of immunocytochemistry with biotin-avidin revelation); (2) protein oxidation (by reaction of protein carbonyls with 2,4-dinitrophenyl-hydrazine followed by immunocytochemistry of dinitrophenyl moieties); and (3) cellular protein thiols (by direct alkylation of sulfhydryl groups with thiol-specific fluorescent reagents possessing different cell permeabilities). The procedures proved able to reveal the subcellular distribution of cytochemical parameters useful as indices of oxidative stress conditions, and may allow redox phenotyping of isolated cells, which would provide an efficient tool in selected experimental models. 相似文献
7.
Four unusual Apiotrichum, isolated from decayed wood of Eucryphia cordifolia Cav., Nothofagus obliqua (Mirb.) Blume, and Laurelia sempervirens Wein., one of which was also isolated from the intestinal tract of Scaptomyza multispinosa Malloch (Diptera), are described and illustrated. These species differ from all the accepted Apiotrichum species (1–3) to warrant their establishment as four new species: Apiotrichum eucryphiae, Apiotrichum osvaldii, Apiotrichum futronensis and Apiotrichum nothofagi. 相似文献
8.
A deterministic predator-prey model is presented for describing the dynamics of a solid tumor in the presence of a specifically
reactive lymphocyte population which is stimulated by, and antagonistic to, the tumor. The qualitative behavior of the solutions
is developed and briefly compared to the results of transplantation experiments. Although the model is primitive, it leads
to predictions that are in general agreement with observation and intuitive expectations. In particular, it is found that:
(1) very low levels of transplanted tumor will not survive in the recipient. (2) At somewhat higher levels, tumor growth will
be uncontrolled in the syngeneic recipient. However, immune intervention if early enough, can lead to control and elimination
of the tumor. (3) At still higher levels of transplanted tumor, no amount of immune intervention will be effective in controlling
the tumor. (4) If the recipients immune system is suppressed prior to transplantation, or is debilitated for any reason, the
chance that the tumor will grow increases. (5) If the recipients immune system is stimulated prior to transplantation, the
chance of tumor survival decreases. (6) The survival of the tumor is much more sensitive to changes in tumor parameters (for
example, antigenicity) than in lymphocyte parameters. In addition it makes the unintuitive prediction that (7) There areisolated instances under which anincrease in the number of lymphocytes canincrease the chance of tumor survival. 相似文献
9.
General formulation of stochastic single- and multi-compartment reversible systems with time-dependent transitions is made.
The correspondence between the stochastic mean and the deterministic value is established in case of time-dependence and it
is shown how the consequence of this can be utilized to compute the distribution and the moments of each individual compartment
of the system. A two-compartment reversible system previously proposed by Cardenas and Matis (1975a) is analyzed on the basis
of the theory. 相似文献
10.
F J Hurtado A M Gutierrez N Silva E Fernandez A E Khan G Gutierrez 《Journal of applied physiology》1992,72(5):1895-1901
We compared the hemodynamic and metabolic alterations produced in rabbits by similar decreases in cardiac output created by inflating a balloon placed in the right ventricle (n = 6) with those produced by an intravenous bolus of Escherichia coli lipopolysaccharide (LPS; SEP group; n = 6). We measured O2 consumption (VO2), O2 transport (TO2), and O2 extraction ratio (ERO2) for the whole animal and also for the left hindlimb. Both groups experienced similar decreases in cardiac output, systemic TO2, and VO2 and similar increases in ERO2. For the hindlimb, TO2 was similar, but VO2 and ERO2 were lower for the SEP group 30 min after LPS administration (P less than 0.05); however, this difference disappeared during the remainder of the experiment. Arterial lactate concentration was greater (P less than 0.05) for the SEP group. There were no differences in skeletal muscle PO2, measured with a multiwire surface electrode, or in cardiac and skeletal muscle concentrations of high-energy phosphates. We hypothesize that a direct effect of LPS on cellular metabolism may have resulted in greater arterial lactate concentration for the SEP group. 相似文献