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31.
Intranuclear cytoplasmic inclusions in aspirates of follicular neoplasms of the thyroid. A report of two cases 总被引:1,自引:0,他引:1
Two cases are reviewed in which the presence of intranuclear cytoplasmic inclusions in fine needle aspiration biopsy specimens of the thyroid suggested a diagnosis of papillary carcinoma. Subsequent surgical specimens were consistent with diagnoses of microfollicular adenoma and follicular carcinoma. These cases suggest that the presence of intranuclear inclusions in epithelial thyroid cells is not limited to papillary and medullary carcinoma, as some authors have suggested. 相似文献
32.
Human serum was fractionated by high resolution agarose isoelectricfocusing and the galactosyltransferase activity profile was determined using the ovalbumin, mucin, glucose and N-acetylglucosamine acceptor assays. The four acceptors gave very similar activity profiles. There were minor quantitative differences in some of the 12 or more peaks of activity detected and the only qualitative difference between them was a minor peak at pH 3.90 (2% of the total activity) which reacted only with the mucin acceptor. This suggests that most of the isoenzymes of human serum galactosyltransferase have broad and similar acceptor specificities and that the heterogeneity seen in serum cannot be accounted for by acceptor-specific forms of the enzyme. 相似文献
33.
Summary Laboratory prescreening ofRhizobium trifolii for acid tolerance, based upon the ability of rhizobia to grow in acid media (pH 4.2) containing Al (15 M), was successful for the selection of strains capable of survival in acid soil.Both sterile and non-sterile soils of varying acidity were inoculated with several strains ofR. trifolii.Acid tolerant strains generally had significantly higher populations at every sample period than an acid sensitive strain. Amelioration of soil acidity by liming improved persistence of all strains. Soil sterilization by autoclaving adversely affected survival of all strains at each soil acidity level.Paper Number 8766 of the Journal Series, North Carolina Agricultural Research Service, Raleigh, NC 27650, USA. 相似文献
34.
Movements and associations of ribosomal subunits in a secretory cell during growth inhibition by starvation
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In Chironomus tentans salivary gland cells, the cytoplasm can be dissected into concentric zones situated at increasing distances from the nuclear envelope. After RNA labeling, the newly made ribosomal subunits are found in the cytoplasm mainly in the neighborhood of the nucleus with a gradient of increasing abundance towards the periphery of the cell. The gradient for the small subunit lasts for a few hours and disappears entirely after treatment with puromycin. The large subunit also forms a gradient but one which is only partially abolished by puromycin. The residual gradient which which is resistant to the addition of the drug is probably due to the binding of some large ribosomal units to the membranes of the endoplasmic reticulum (J.-E. Edstrom and u. Lonn. 1976. J. Cell Biol. 70:562-572, and U. Lonn and J.-E. Edstrom. 1976. J. Cell. Biol. 70:573-580). If growth is inhibited by starvation, only the puromycin-sensitive type gradient is observed for the large subunit, suggesting that the attachment of these newly made subunits to the endoplasmic reticulum membranes will not occur. If, on the other hand, the drug-resistant gradient is allowed to form in feeding animals, it is conserved during a subsequent starvation for longer periods than in control feeding animals. This observation provides a further support for an effect of starvation on the normal turnover of the large subunits associated with the endoplasmic reticulum. These results also indicate a considerable structural stability in the cytoplasm of these cells worth little or no gross redistribution of cytoplasmic structures over a period of at least 6 days. 相似文献
35.
Davey K. G., Sommerville R. I. and Rogers W. P. 1982. The effect of ethoxyzolamide, an analogue of insect juvenile hormone, nor-adrenaline and iodine on changes in the optical path difference in the excretory cells and oesophagus during exsheathment in Haemonchus contortus. International Journal for Parasitology12: 509–513. Ethoxyzolamide, an inhibitor of carbonic anhydrase, markedly inhibits exsheathment of Haemonchus when the larvae are subsequently exposed to an exsheathing stimulus of CO2 at 38.5°C. Ethoxyzolamide at 2 × 10?5M does not prevent the increase in optical path difference in the oesophageal region which normally accompanies exsheathment, but markedly inhibits the increase in optical path difference in the excretory cells. An analogue of juvenile hormone (JHA; the methyl ester of 3,7,11 trimethyl-7,11-dichloro-2-dodecenic acid) does not affect the optical path difference in either the oesophagus or the excretory cells of ensheathed worms. When worms are artificially desheathed by exposure to NaOCl, a procedure which mimics the effect of CO2 upon the oesophagus, but which does not affect the excretory cells, subsequent exposure to JHA at room temperature increases the optical path difference in the excretory cells. This increase is enhanced by subsequent incubation of the worms at 38.5°C at 30–60 min and further enhanced when CO2 is present during the incubation at 38.5°C. The stimulation of the excretory cells by JHA is inhibited by ethoxyzolamide at 2 × 10?5M. Noradrenaline at 10?3M has no effect on ensheathed larvae, but causes an increase in optical path difference in the excretory cells of larvae desheathed with NaOCl. This increase is inhibited by ethoxyzolamide. A brief exposure to I2 blocks the response of the excretory cells of both CO2 and JHA, but does not significantly reduce the effect of nor-adrenaline. On the basis of these and previous results, it is proposed that both CO2 and JHA stimulate a hypothetical CO2 receptor which leads to the release of nor-adrenaline. The noradrenaline in turn stimulates, either directly or indirectly, the excretory cells. 相似文献
36.
In juvenile wild rats, bronchus-associated lymphoid tissue (BALT) development was similar to that seen in adult specified-pathogen-free rats. In adult wild rats the BALT was widespread. In one animal infected with a mycoplasma-like organism, a region of bronchoepithelium overlying a large BALT nodule was seen, through which lymphocytes appeared able to pass to make direct contact with the bronchial lumen: the significance of this observation is discussed. There was no evidence of infection in lungs from any of the specified-pathogen-free animals, where small foci of BALT were seen. 相似文献
37.
38.
A total of 203 samples of faeces from 124 cows was examined for the presence of Yersinia enterocolitica and related species by a variety of isolation procedures. Cold enrichment at 5°C for three weeks, followed by plating on cefsulodin-irgasannovobiocin agar yielded Yersinia species most frequently. Yersinia enterocolitica or related species were isolated from 50% of the cows. 相似文献
39.
Glycine argyrea accession G1420 was evaluated for its response to inoculation with Agrobacterium rhizogenes strains LBA9402 and A4T, carrying wild type Ri plasmids, and by strains R1601 and A4TIII with engineered plasmids. Hypocotyls from young seedlings were the most responsive in producing roots at inoculation sites. Root production was also dependent on bacterial concentration. Excised, cultured roots produced green nodular callus which regenerated shoots on SC2 medium containing 1.1 mg l–1 6-benzylaminopurine and 0.005 mg l–1 indole-3-butyric acid. The transformed nature of the roots and of callus regenerating shoots was confirmed by the presence of opines and by dot blot analysis for Ri TL-DNA. Tissues regenerated from roots transformed by A. rhizogenes strains R1601 and A4TIII exhibited NPTII enzyme activity, confirming the stable integration and expression of the chimaeric kanamycin resistance gene in transgenic tissues.Abbreviations BAP
6-benzylaminopurine
- IBA
indole-3-butyric acid
- NPTII
neomycin phosphotransferase II
- SDS
sodium dodecyl sulphate 相似文献
40.
K R Davey 《Applied microbiology》1990,56(2):566-568
A theoretical model was developed and used to estimate quantitatively the "worst case", i.e., the longest, time to reach equilibrium temperature in the center of a clump of bacteria heated in fluid. For clumps with 10 to 10(6) cells heated in vapor, such as dry and moist air, and liquid fluids such as purees and juices, predictions show that temperature equilibrium will occur with sterilization temperatures up to 130 degrees C in under 0.02 s. Model development highlighted that the controlling influence on time for heating up the clump is the surface convection thermal resistance and that the internal conduction resistance of the clump mass is negligible by comparison. The time for a clump to reach equilibrium sterilization temperature was therefore decreased with relative turbulence (velocity) of the heating fluid, such as occurs in many process operations. These results confirm widely held suppositions that the heat-up time of bacteria in vapor or liquid is not significant with usual sterilization times. 相似文献