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91.
Colloid carcinoma of the breast with concomitant metastasis and a tuberculous lesion in the axillary lymph nodes. A case report. 总被引:1,自引:0,他引:1
A 30-year-old woman presented with a lump in the left breast and left axillary lymphadenopathy that, on fine needle aspiration cytology (FNAC), proved to be duct cell carcinoma with metastasis. Histology of the radical mastectomy specimen showed a mixed colloid carcinoma. Axillary lymph nodes revealed a variety of pathologic changes consisting of reactive hyperplasia, tuberculosis and metastasis. A combination of a tuberculous lesion and metastasis in the same lymph nodes was also found. During follow-up, after radiotherapy, the patient developed left supraclavicular and right cervical lymphadenopathy that, on FNAC, revealed a tuberculous lesion and metastasis, respectively. The rarity of this condition with double pathology is highlighted, and the reason behind the limitations of FNA in subtyping the primary malignancy and its failure to detect the tuberculous lesion in the axillary lymph node are discussed. 相似文献
92.
The genomic organization and chromosomal location of theβ-tubulin isogenes inLeishmania donovani promastigotes has been studied by nucleic acid hybridization techniques using a cloned β-tubulin gene. We have cloned aβ-tubulin gene fragment, 3.3 kbp long, from genomic DNA ofLeishmania donovani using a heterologousβ-tubulin DNA as probe. Restriction maps of this clone have been prepared. It has been estimated that there are approximately
11–15 copies of theβ-tubulin genes per haploid genome. The majority of these isogenes are arranged in a tandem repeat with a length of 3.5 kbp
on a single chromosome. In addition a few dispersed gene copies at different chromosomal loci were detected by pulse field
gradient gel electrophoresis. Part of the internal coding region of the gene has been sequenced to confirm the identity of
theβ-tubulin clone and is found to be nearly identical to that ofLeishmania mexicana amazonensis. 相似文献
93.
94.
Microbial production of methionine is reviewed with 71 references. The review describes different methionine-producing organisms,
as well as analog-resistant regulatory mutants, their optimum cultural conditions and yields. The pathways of methionine biosynthesis
and their regulation are discussed. 相似文献
95.
VirE1 protein mediates export of the single-stranded DNA-binding protein VirE2 from Agrobacterium tumefaciens into plant cells. 总被引:10,自引:5,他引:5 下载免费PDF全文
Agrobacterium tumefaciens transfers single-stranded DNAs (T strands) into plant cells. VirE1 and VirE2, which is a single-stranded DNA binding protein, are important for tumorigenesis. We show that T strands and VirE2 can enter plant cells independently and that export of VirE2, but not of T strands, depends on VirE1. 相似文献
96.
The larvae of the dipteran insect, Chironomus ramosus, found in Shillong, India, contain eleven (11) hemoglobin (Hb) components of which three are monomers (CI, CIV and CVI) and seven are dimers (CIII, CV, CVII, CVIII, CIX, CX and CXI), while one (CII) exists in both monomeric and dimeric states.Four monomeric components were isolated, purified and partially characterized. The N-terminal amino acids were determined and showed glycine for CI and leucine for the other components (CII, CIV and CVI).Three hemoglobin components were found to be present in all stages of larval development, except the first instar larvae. Some Hb components were synthesized in a particular instar, as revealed by electrophoretic appearance.Electrophoretic mobilities of seven components and N-terminal amino acid residues of two components of Hb were similar in both Chironomus ramosus and Chironomus thummi thummi. 相似文献
97.
98.
Echinochloa colona regeneration via organogenesis in callus cultures derived from leaf base and mesocotyl expiants andin vitro flowering were achived. Shoot bud regeneration was achieved on Murashige and Skoog’s (MS) basal medium supplemented with
6.66 μM 6-benzylaminopurine (BAP), 2.68 μM 1-naphthalene acetic acid (NAA) and 3 % (m/v) saccharose. Regenerated shoots were
rooted on half strength basal MS medium with 2 % (m/v) saccharose devoid of growth regulators. About 90 -95 % of rooted plantlets
survived in the greenhouse.In vitro flowering was induced in the regenerated shoots derived from callus on half strength MS medium supplemented with 4.4 μM BAP,
74.07 μM adeninesulphate, 0.72 μM gibberellic acid, and 3 % (m/v) saccharose. The frequency ofin vitro flowering was 80 – 90 % in three repeated experiments. Fertile seeds were recovered fromin vitro grown plantlets which were subsequently germinated into plants.
Acknowledgement: The authors wish to thank to the Department of Environment and Forests, Government of India for financial
assistance to undertake this investigation. 相似文献
99.
The stem of the peanut plant contains two lectins, a methyl -mannoside specific lectin (SL-I) and a lactose/cellobiose specific lectin (SL-II). These lectins are found to be developmentally regulated and maximum activites are observed in 3–4-weeks-old plants. The two lectins SL-I and SL-II have been purified from 3-week-old stem by affinity chromatography on Sephadex G-50 and guar gum matrices respectively. Both are glycosylated lectins and have the identical subunit molecular weight of 31 kDa. 相似文献
100.
The effect of the antiarrhythmic drugs lidocaine, quinidine and procainamide on macrophage function was investigated in RAW 264.7 mouse monocytic macrophage cell. Cells stimulated by either zymosan or phorbol ester were found to generate both superoxide (O
2
–
) and H2O2. The production of O2 was detected as superoxide dismutase inhibitable ferricytochrome c reduction. H2O2 production was monitored in both chemical and flow cytometric fluorescent assays. Although all three drugs inhibited both O2 and H2O2 release in a dose dependent manner, only quinidine was found to have significant inhibitory effects. The amounts of quinidine required to cause a 50% inhibition in O2 production in zymosan and phorbol ester stimulated cells were found to be 250 M and 300 M, respectively and the amounts required to cause one-half optimum levels of H2O2 production in these cells were found to be 50 M and 100 M, respectively. The effect of these drugs on O2 producing NADPH oxidase was investigated and only procainamide was found to have a significant effect (p<0.001) in inhibiting the oxidase activity. Lidocaine and quinidine had no significant effect on the activation of the respiratory burst oxidase. A sensitive and convenient differential phagocytosis assay was devised on the basis of number of particles engulfed by individual phagocytes using flow cytometric techniques. It appears to be remarkably free of interference and was applied to investigate the role of antiarrhythmic drugs on the phagocytosis of fluorescent latex beads. All three antiarrhythmic drugs inhibited phagocytosis of latex beads in a dose dependent manner irrespective of the number of particles phagocitized by the cells. The results of these studies do not conclusively establish a mechanism of action of these drugs on the generation of O2 and H2O2 by stimulated macrophages; nevertheless, it is interesting that all three drugs inhibited the phagocytic activity. 相似文献