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101.
The authors described 21 patients aged 37 to 83 with ossification of the posterior longitudinal ligament (10 with ischemic myelopathy, 6 with aftermaths of a trauma of the cervical spine, and 5 with the radicular syndrome on the basis of vertebral osteochondrosis. X-ray signs of three types of ossification of the posterior longitudinal ligament were defined and specified: linear, curved and mixed. The linear type was more frequently observed in the cervical spine whereas the curved type was more frequent in the lumbar spine. 相似文献
102.
Thyroid hormones are involved in copper and zinc distribution in rat tissues. We examined the influence of thyroparathyroidectomy
(TPTY) and of a replacement therapy by T4 on Cu and Zn organ distribution. MT levels were also measured both in basal conditions
and after induction by cadmium. The results confirm that a lack of T4 modified Cu and Zn in serum and tissues. In serum, TPTY
increased Cu (+15%) and ceruloplasmin (+18%), and decreased Zn (−18%). In tissues, Cu was altered in liver (+13%), kidney
(−24%), heart (−16%) duodenum (−18%), and Zn in liver (+25%) and kidney (−10%). The soluble fractions (100,000 g supernatant)
were mainly affected in liver and kidney, and the subcellular fractions in heart and duodenum. MT levels were modified in
basal conditions only in liver (+57%) and kidney (−36%). T4 administration partially prevented the effect of TPTY on both
elements and MT concentrations. Therefore, no evidence is provided for a direct role of T4 in the metabolism of MT in a way
comparable to the effects of glucocorticoids. However, MT could mediate the consequences of TPTY on metal distribution in
certain organs, such as liver and kidney. 相似文献
103.
104.
L Paturle-Lafanechère B Eddé P Denoulet A Van Dorsselaer H Mazarguil J P Le Caer J Wehland D Job 《Biochemistry》1991,30(43):10523-10528
Brain tubulin preparations contain an abundant type of tubulin which does not undergo the normal cycle of tyrosination-detyrosination, and whose nature is still unknown. We have used peptide sequence analysis and mass spectrometry combined with immunological procedures to show that this non-tyrosinatable tubulin has a specific primary structure. It differs from the tyrosinated isotype in that it lacks a carboxy-terminal glutamyl-tyrosine group on its alpha-subunit. Thus, non-tyrosinatable tubulin originates from a well-defined posttranslational modification of the tubulin primary structure which is located at the expected site of activity of tubulin tyrosine ligase. This probably accounts for the reason why it cannot be tyrosinated. The significance of this abundant brain isotubulin and the metabolic pathway involved in its formation remain to be elucidated. This should shed light on the relation between the structural diversity of the carboxy terminus of alpha-tubulin and the regulation of functional properties of microtubules. 相似文献
105.
A METHOD FOR ESTIMATING MASS OF LARGE PINNIPEDS 总被引:3,自引:1,他引:2
Fifty-two male elephant seals were weighed and photographed at Año Nuevo State Reserve, California, to establish a predictive relationship between photographically measured morphological variables (length, side area, and girth area) and body mass. Regression of mass on these variables revealed that side area, roughly equivalent to a longitudinal cross-section, was the most useful single variable for predicting mass, and that adding the other two variables to side area slightly improved the accuracy of the photogrammetric technique. Curvilinear regressions based on a power model provided the best predictive relationships. This technique may prove useful for estimating body mass of other pinnipeds. 相似文献
106.
James H. Resau Kosaku Sakamoto John R. Cottrell Eric A. Hudson Stephen J. Meltzer 《Cytotechnology》1991,7(3):137-149
Organ explant culture models offer several significant advantages for studies of patho-physiologic mechanisms like cell injury, secretion, differentiation and structure development. Organs or small explants/slices can be removed in vivo and maintained in vitro for extended periods of time if careful attention is paid to the media composition, substrate selection, and atmosphere. In the case of human tissues obtained from autopsy or surgery, additional attention must be paid to the postmortem interval, temperature, hydration, and cause of death. Explant organ culture has been effectively utilized to establish outgrowth cell cultures and characterize the histiotypic relationships between the various cell types within an organ or tissue.J. Resau is a visiting scientist at the NCI-LMO-DCE in Frederick, MD 21702, U.S.A.K. Sakamoto is a visiting scientist from the Department of Surgery, Gunma University School of Medicine, Maebashi, Japan 相似文献
107.
Maurizio Rossetto Kingsley W. Dixon Eric Bunn 《In vitro cellular & developmental biology. Plant》1992,28(4):192-196
Summary Aeration of tissue cultured rare Australian plantsConostylis wonganensis S.D. Hopper (Haemodoraceae);Diplolaena andrewsii Ostenf.;Drummondita ericoides Harvey (Rutaceae);Eremophila resinosa F. Muell. (Myoporaceae);Eucalyptus ‘graniticola’ (Myrtaceae);Lechenaultia pulvinaris C. Gardner (goodeniaceae); andSowerbaea multicaulis E. Pritzel (Liliaceae) has been found to reduce vitrification in sensitive species as well as significantly improving shoot
quality and transfer to soil in most study species. A simple 7-mm hole with a double-layer insert of filter paper in the polypropylene
screw lids of the culture vessel decreased shoot vitrification over a 4-wk culture period. The method has implications for
facilitating the tissue culture of other rare Australian plants and reducing the occurrence of this developmental abnormality. 相似文献
108.
Eric Thybaud 《Hydrobiologia》1990,190(2):137-145
Acute toxicity and bioconcentration capacities of lindane and deltamethrin were studied in Rana temporaria tadpoles and in mosquitofish. These studies show that the toxicity of deltamethrin is about 100 to 1 000 times greater than
that of lindane and bioconcentration factors are very different for these two insecticides. The bioconcentration factor of
lindane, a stable chemical, low volatility, hydrophobic and a poorly metabolized molecule is considerable in either static
or flow through contamination systems. For deltamethrin, an quickly metabolized molecule, this factor is weak or null.
Moreover a comparison of various methods of contamination (static or flow through systems) showed that the experimental conditions
of exposure to the insecticide strongly influence the concentration in the tested species.
Toxicité aigüe et bioconcentration du lindane et de la deltaméthrine par les tetards de Rana temporaria et les gambusies (Gambusia affinis)相似文献
109.
John E. Byfield Raquel Zerubavel Eric W. Fonkalsrud 《Cancer immunology, immunotherapy : CII》1982,14(2):117-123
Summary The in vitro and in vivo activity has been investigated of antisera prepared against a murine (C-1300) neuroblastoma line (MNB) capable of differentiation. An antibody-dependent cellular cytotoxicity (ADCC) reaction was employed using rat spleen cells (RSC). ADCC activity in vitro (using 51Cr-release) was shown, but a maximum of only 50% of the immunologically releasable 51Cr was achieved. Nevertheless, in vivo (syngeneic mouse-tumor flank assay) significant delays were obtained in tumor onset and lethality. Under ideal circumstances, i.e., coating of tumor cells prior to inoculation and high RSC effector cell ratios, a significant number of animals could be cured of substantial tumor burdens (106 cells). While close proximity of the site of injection of effector cells was required (ectopic injections of RSC were ineffective), the anti-MNB ADCC was shown to be quite active in vivo without external precoating of the cells with antisera. RCS obtained from BCG-treated rats were more numerous and slightly more effective. RSC obtained from -radiated animals retained normal activity. With appropriate antisera this approach could be useful under selected clinical circumstances. 相似文献
110.