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261.
Primary malignant melanoma of uterine cervix is a rare neoplasm. Its diagnosis on cervical fine needle aspiration cytology, a first of its kind in the literature, has been reported. Although cervix is a rare site for melanoma, cytopathologists should be familiar with it and be able to diagnose this entity on cervical cytology when pigment containing tumour cells are present. In a patient with visible growth on cervix, fine needle aspiration cytology may prove to be a useful diagnostic tool, especially when cervical smear/scrape cytology is non-diagnostic.  相似文献   
262.
The aim of this study was to evaluate the diagnostic value of fine needle aspiration cytology (FNAC) in the assessment of palpable supraclavicular lymph nodes. The material was analysed in 218 cases with enlarged supraclavicular lymph nodes in which FNAC was performed by the conventional method. In all cases cytological examination was performed on-site after staining the smears by the Papanicolaou method. In addition, air-dried smears, fixed smears, filter preparations from needle washings and cell blocks were studied. The FNAC diagnosis was supported by examining cell blocks which added the reliability of histological architecture; further support was obtained by tissue biopsy and/or comparison with the primary tumour in some of the cases. Eleven cases were diagnosed as inflammatory lesions and 41 cases were unsatisfactory because of scanty/acellular samples (despite two to three repeat samplings). However, in five of these, malignant tumours were later found on biopsy, which was done for persistent enlargement of the supraclavicular lymph node(s). Fifty-three cases were diagnosed as negative for malignancy (normal cellular elements, n=15; reactive elements, n=38) and 12 cases were suspicious of malignancy. In 11 cases a diagnosis of lymphoma was made on histology and in 90 cases metastatic tumours were diagnosed. The overall sensitivity was 92.7%, specificity 98.5%, positive predictive value 97.3% and the negative predictive value was 94.8%. Based on our study we feel that FNAC of palpable supraclavicular lymph nodes as a first line of investigation is a cost-effective procedure and is not only useful in the diagnosis of various lesions but can also help in deciding on appropriate management. Furthermore, the histological architecture from cell blocks can be correlated with cytology, and such material can be used for appropriate histochemical and immunomarker studies, which can be useful in enhancing the diagnosis.  相似文献   
263.
264.
The syntheses of (±) 2α,6β-diethyl-7α-ethynyl-3α-(p-hydroxyphenyl)-trans-bicyclo[4.3.0]nonan-7β-ol (8), (±)2β,6β-diethyl-7α-ethynyl-3β-(p-methoxyphenyl)-trans-bicyclo[4.3.0]nonan-7β-ol (12) and (±) 2α,6β-diethyl-7α-ethynyl-3β-(p-hydroxyphenyl)-trans-bicyclo[4.3.0]nonan-7β-ol (18) and their derivatives, which are essentially B-seco-steroids having cis-anti-trans, cis-syn-trans and trans-anti-trans geometries have been carried out. A study of their antiimplantation activities (AI) and receptor binding affinities (RBA) show that trans-anti-trans compounds are biologically most potent, followed by the corresponding cis-anti-trans and cis-syn-trans compounds. The most potent compound 18 is active at 1 mg/kg in rats. Introduction of 7α-ethynyl group increases their AI activity; however, no significant effect on their RBA is observed.  相似文献   
265.
-Galactosidase and streptokinase expression was tested under the control of the T7 promoter in batch and fed-batch cultures. An Escherichia coli host GJ1158, which contained the T7 RNA polymerase gene under the osmo-responsive proUp promoter, was used for expression studies. -Galactosidase expression was enhanced from 26 mg l–1 to 127 mg l–1 in batch culture when a combination of sucrose and sorbitol was used instead of salt as an inducer. Similarly in fed-batch cultures 140 mg streptokinase l–1 was formed with sucrose and sorbitol induction which was higher than that achieved with IPTG induced cultures.  相似文献   
266.
The innate immune system recognizes microorganisms through a series of pattern recognition receptors that are highly conserved in evolution. Insects have a family of 12 peptidoglycan recognition proteins (PGRPs) that recognize peptidoglycan, a ubiquitous component of bacterial cell walls. We report cloning of three novel human PGRPs (PGRP-L, PGRP-Ialpha, and PGRP-Ibeta) that together with the previously cloned PGRP-S, define a new family of human pattern recognition molecules. PGRP-L, PGRP-Ialpha, and PGRP-Ibeta have 576, 341, and 373 amino acids coded by five, seven, and eight exons on chromosomes 19 and 1, and they all have two predicted transmembrane domains. All mammalian and insect PGRPs have at least three highly conserved C-terminal PGRP domains located either in the extracellular or in the cytoplasmic (or in both) portions of the molecules. PGRP-L is expressed in liver, PGRP-Ialpha and PGRP-Ibeta in esophagus (and to a lesser extent in tonsils and thymus), and PGRP-S in bone marrow (and to a lesser extent in neutrophils and fetal liver). All four human PGRPs bind peptidoglycan and Gram-positive bacteria. Thus, these PGRPs may play a role in recognition of bacteria in these organs.  相似文献   
267.
A reversed-phase high-performance liquid chromatographic method using a mobile phase of acetonitrile-methanol-trifluoroacetic acid-water (16.1:7.2:0.1:76.6, v/v/v/v) at a flow rate of 1.0 ml min(-1) on a LiChrospher RP-18 column with UV (254 nm) detection has been developed for the separation of sulfadoxine and its metabolite N-acetyl sulfadoxine in plasma. No interferences due to endogenous compounds or common antimalarial drugs were noticed. The limit of detection for sulfadoxine and N-acetyl sulfadoxine was 0.01 microg ml(-1) with a signal-to-noise ratio of 5:1 while the limit of quantification was 2.5 microg ml(-1). Intra-day mean relative standard deviations (RSD's) for sulfadoxine and N-acetyl sulfadoxine were 2.6 and 2.8%, respectively, while mean inter-day RSD's for sulfadoxine and N-acetyl sulfadoxine were 2.4 and 2.8%, respectively. Extraction recoveries averaged 90.6% for sulfadoxine and 86.9% for N-acetyl sulfadoxine. The method was applied for the assay of sulfadoxine and its metabolite N-acetyl sulfadoxine in plasma from Plasmodium falciparum malaria patients. Mean plasma sulfadoxine concentrations on day 2 (51 h) from samples collected from sensitive and resistant P. falciparum patients treated with three tablets of Fansidar were 62.8 and 60.5 microg ml(-1), respectively. Mean ratio of N-acetyl sulfadoxine to sulfadoxine was 9.1% for responders and 13.9% for non-responders which revealed that higher amounts of the metabolite N-acetyl sulfadoxine were present in non-responders. The method described should find an application in the therapeutic monitoring of malaria patients.  相似文献   
268.
Inappropriate disposal of municipal sludge (MS) results in the leaching of toxic metals and organic chemicals, which can contaminate the surface and ground water leading to the serious health hazards. In this study, the genotoxic potential of the leachate prepared from MS sample was examined in mouse bone marrow cells through chromosomal aberrations (CA), micronucleus test (MT) and comet assay. Analysis of metals and physicochemical parameters of the leachate was also carried out to correlate the genotoxic results. The dried sludge showed high concentrations of heavy metals, viz. Cr, Cu, Pb and Ni. However, in 10% leachate, concentrations of these metals were manifold lower than that of obtained in dried sludge. Male mice orally gavaged to leachates (0.1-0.4 ml/mouse/day) for 15 days revealed significant (P<0.01, P<0.001) inhibition of mitotic index (MI) and induction of chromatid/chromosome fragments and breaks in all the treatment groups. The effect was observed to be dose-dependent. Treatment of mice with leachates also induced significant (P<0.001) frequencies of micronucleated polychromatic erythrocytes (MNPCE). The results of comet assay revealed a statistically significant (P<0.05 and <0.01) DNA damage in bone marrow cells exposed to 0.2-0.4 ml/mouse/day. Findings of the present study indicate that the constant exposure of MS leachate can cause genotoxic effects in mammals and suggest risks in human population.  相似文献   
269.
Various measurements are still considered to be important for making decisions regarding the approach in reduction mammaplasty, even though the vast majority of techniques used are based on an inferior pedicle. This study was performed to analyze the variability of the suprasternal notch-to-nipple and nipple-to-inframammary fold distance measurements when using the inferior pedicle technique. In 92 patients, 184 breasts having various volumes were measured preoperatively, and the variability of the measurements of the suprasternal notch-to-nipple and nipple-to-inframammary fold distance was analyzed. The values of the distance from the suprasternal notch to nipple were dispersed over a wide range with a trimodal distribution, with peaks at the intervals of 23 to 27 cm, 28 to 33 cm, and 34 to 45 cm. In contrast, the values of the nipple-to-inframammary fold distance showed a normal distribution pattern, with the peak at 14 cm. The distance from the suprasternal notch to nipple has a fair relationship to the inframammary fold-to-nipple distance, the latter being concentrated in a smaller range (r = 0.51). The former is often used to decide whether a free-nipple graft should be performed. However, the relative consistency of the latter measurement has led to the conclusion that the free-nipple graft technique need never be considered.  相似文献   
270.
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