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False negative cytologic diagnosis of breast carcinoma. 总被引:4,自引:0,他引:4
OBJECTIVE: To study the reasons for interpretive errors in false negative diagnosis of breast carcinoma on fine needle aspiration cytology material. STUDY DESIGN: We reviewed only those histologically proved malignant cases where the cytologic material was abnormal and to some extent misinterpreted. RESULTS: There were four lobular carcinomas and one each case of in situ, infiltrating duct, medullary and tubular carcinoma. Smears of lobular carcinomas were hypocellular overall, and the cells showed minimal nuclear pleomorphism. In situ, medullary and tubular carcinoma were associated with fibrocystic changes. The presence of bipolar cells and stromal fragments was misleading in cases of infiltrating duct carcinoma. CONCLUSION: The presence of associated fibrocystic disease may be a misleading factor since it may mask a malignancy. Hypocellularity and relatively nuclear monomorphism were the most common reasons for failure to diagnose malignant breast lesions. Careful attention should be paid to extreme nuclear monomorphism and absence of naked bipolar cells. A cytologically atypical or suspicious diagnosis together with radiologic suspicion should suggest a diagnosis of malignancy. 相似文献
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The levels of prostaglandins (PGs) were measured by radioimmunoassay in the interimplantation and the implantation sites as well as in the implantation site without the blastocyst in the rabbit on day 7 of pregnancy (168h ). The concentrations of PGs were also determined in the blastocyst (PGF:101.59+?4.33 and PGE-A:29.74+?3.11 ng/blastocyst, n=6) and the blastocel fluid (PGF:253.55+?39.56 and PGE-A:83.29+?6.60 ng/100 ul, n-4) on day 7. The levels of both PGF and PGE-A were significantly higher in the implantation site as compared to interimplantation site (PGF:73.63±6.68 vs. 0.59±0.21 and PGE-A:25.52±3.30 vs. 1.22±0.18 ng/100 mg wet weight n=8). The removal of the blastocyst from the implantation site drastically reduced the concentrations of PGs in this site (PGF:8.71±2.80 and PGE-A:1.64±0.12 ng/100 mg wet weight, n=8). The results provide evidence that the blastocyst is the major source of PGs which contribute to the hige concentration in the implantation site in the rabbit. 相似文献
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Phosphatidyl inositol has been found to inhibit strongly the activity of a cyclic AMP-independent protein kinase located on the external surface of goat epididymal intact spermatozoa. Phosphatidyl inositol at a concentration as low as 10 micrograms/ml inhibited nearly 50% of the ecto-kinase activity for the phosphorylation of the exogenous protein substrate: casein. Phosphatidyl ethanolamine at a relatively high concentration (125 micrograms/ml) inhibited slightly (approx 25%) the activity of the enzyme whereas other phospholipids: phosphatidyl serine and choline, diacyl glycerol, phosphatidic acid and myo-inositol-2-phosphate had no appreciable effect on the kinase activity. Phosphatidyl inositol has also served as a potent inhibitor of the phosphorylation of sperm ecto-phosphoproteins by the endogenous kinase activity of intact spermatozoa. By thin layer chromatography it has been shown that the observed inhibitory effect of the phospholipid was not due to any impurities or degraded products of phosphatidyl inositol. Phosphatidyl inositol inhibited the kinase activity noncompetitively with respect to casein and Mg2+ but uncompetitively with respect to ATP. The results raised the possibility that phosphatidyl inositol-mediated high affinity inhibition of protein kinase(s), may constitute a novel mechanism for the regulatory actins of the phospholipid in mammalian cells. 相似文献
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Summary A rapid exchange procedure using ammonium acetate as an extractant was developed for measurement of cation exchange capacity
(CEC) of plant roots. The CEC values obtained with 1∶100 and 1∶200 root/solution ratios were almost equal, though the values
increased with length of the time of immersion in both the root/solution ratios. The method gave higher CEC values with fresh
roots as compared to dried roots. However, dried milled and dried unmilled roots gave identical values. 相似文献
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Joydip Karmakar Rajib Roychowdhury Rup Kumar Kar Debal Deb Narottam Dey 《Physiology and Molecular Biology of Plants》2012,18(2):125-132
A total of ten rare indigenous rice landraces of West Bengal were screened for germination potential and seedling growth under varying concentrations of sodium chloride (NaCl) and polyethylene glycol (PEG) solutions as osmotic stress inducing agents. Among the studied rice landraces Kelas and Bhut Moori showed highest degree of tolerance to induced osmotic stresses. Proline content of the studied lines was also determined. Genetic relationship among the studied rice landraces was assessed with 22 previously reported osmotic stress tolerance linked Simple Sequence Repeat (SSR) markers. The identified allelic variants in form of amplified products size (molecular weight) for each SSR marker were documented to find out allele mining set for the linked markers of the studied genotypes in relation to osmotic stress tolerance. A Microsatellite Panel was constructed for the different allelic forms (size of amplified products) of each used marker. Among 22 SSR markers, ten showed unique alleles in form of single specific amplified product for the studied four genotypes which can be used for varietal identification. Genetic relationship among the studied rice lines was determined and a dendrogram was constructed to reveal their genetic inter-relationship. Polymorphism Information Content (PIC) for each used marker was also calculated for the studied rice lines. 相似文献
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Nirmalya Dey D.J. Chattopadhyay 《Archives Of Phytopathology And Plant Protection》2013,46(9):1026-1038
Rice necrosis mosaic virus-inoculated jute plants looked more juvenile with enhanced leaf size than control ones. Such enlarged leaves and those from control ones were collected separately and extracted in chilled methanol. The crude tissue extract in case of inoculated ones showed three times higher activity in bioassay for cytokinin over control. Biological assay with fractions of crude extract separated by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) was ascertained, and one fraction from inoculated sample showing higher activity in terms of growth over respective control was selected. Ultraviolet/visible absorbance spectra of TLC-separated fractions revealed the presence of different quantities of similar kind of compounds in both control and inoculated samples. A major compound with same m/z value of 217.1 was found in both cases as revealed through electrospray ionisation mass spectrophotometry analysis along with some other minor compounds. Different proton–proton coupling and a molecular structure of the highly substituted aliphatic groups were found in the material from inoculated sample having higher cytokinin-like activity than the control one, which was noticed through 1H one-dimensional nuclear magnetic resonance analysis. 相似文献