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1.
Breast cancer is one of the top three commonly caused cancers worldwide. Triple Negative Breast Cancer (TNBC), a subtype of breast cancer, lacks expression of the oestrogen receptor, progesterone receptor, and HER2. This makes the prognosis poor and early detection hard. Therefore, AI based neural models such as Binary Logistic Regression, Multi-Layer Perceptron and Radial Basis Functions were used for differential diagnosis of normal samples and TNBC samples collected from signal intensity data of microarray experiment. Genes that were significantly upregulated in TNBC were compared with healthy controls. The MLP model classified TNBC and normal cells with anaccuracy of 93.4%. However, RBF gave 74% accuracy and binary Logistic Regression model showed an accuracy of 90.0% in identifying TNBC cases. 相似文献
2.
Female C57BL/Tw mice were given 5 daily injection of 20 micrograms testosterone (T), 100 micrograms 4-hydroxy-4-androstene-3, 17-dione (4-HA), 100 micrograms 6-methylene-4-pregnene-3, 20-dione (6-MP), 4-HA + 6-MP, T + 4-HA, T + 6-MP, and T + 4-HA + 6-MP starting on the day of birth. The animals were ovariectomized at 30 days or 90 days of age and were killed at 150 days. The incidence of polyovular follicles (PF) at 30 days of age was significantly increased by neonatal treatment with T. By contrast, the PF incidence was significantly reduced by injections of 4-HA given simultaneously with T. Neonatally T- or T + 6-MP-treated 90-day-old mice had ovaries containing follicles and hypertrophied interstitial cells but no corpora lutea. By contrast, T + 4-HA (64%)- and T + 4-HA + 6-MP (82%)-treated mice had ovaries with corpora lutea. In the T + 4-HA + 6-MP (82%)-treated mice had ovaries with corpora lutea. In the T + 4-HA + 6-MP-treated, 150-day-old, ovariectomized mice, the number of mice showing vaginal epithelial stratification was significantly decreased as compared with T-treated mice. There were no significant differences in the number of layers, thickness, and mitotic rate of vaginal epithelium of T-treated mice compared with mice treated with T + 4-HA, T + 6-MP, or T + 4-HA + 6-MP. The present results indicate that development of PF and persistent anovulation are due to the direct action of estrogen (E) derived from T upon neonatal ovarian follicles and the neonatal hypothalamo-hypophysial system, and that T itself can induce ovary-independent vaginal changes, although 5 alpha-reduced androgen and estrogen derived from T seem to be more effective in this regard. 相似文献
3.
Aletaha D Nell VP Stamm T Uffmann M Pflugbeil S Machold K Smolen JS 《Arthritis research & therapy》2005,7(4):R796-R806
Introduction
Frequent assessments of rheumatoid arthritis (RA) disease activity allow timely adaptation of therapy, which is essential in preventing disease progression. However, values of acute phase reactants (APRs) are needed to calculate current composite activity indices, such as the Disease Activity Score (DAS)28, the DAS28-CRP (i.e. the DAS28 using C-reactive protein instead of erythrocyte sedimentation rate) and the Simplified Disease Activity Index (SDAI). We hypothesized that APRs make limited contribution to the SDAI, and that an SDAI-modification eliminating APRs – termed the Clinical Disease Activity Index (CDAI; i.e. the sum of tender and swollen joint counts [28 joints] and patient and physician global assessments [in cm]) – would have comparable validity in clinical cohorts. 相似文献4.
6-Methylene progesterone (6MP) is an irreversible in vitro kcat inhibitor of rat prostate 5 alpha-reductase, the enzyme which converts testosterone (T) to dihydrotestosterone (DHT). Treatment of adult rats with 6MP or diethylstilbestrol (DES) decreased the weight of the ventral prostate (VP) by 45%, while castration reduced it by 86%. Histologically, the 6MP-treated VP were indistinguishable from those of controls, while the VP from DES-treated rats showed fibrous stromal hypertrophy as in castrated rats. The prostatic hydroxyproline content, an index of collagen levels, was enhanced by castration or DES, but was not significantly increased by 6MP. Within 2 days of 6MP treatment, the 5 alpha-reductase activity was reduced by 46% and ornithine decarboxylase (ODC) activity was lowered by 27%. During this time the prostatic acid phosphatase activity increased 42% and remained elevated with continued exposure to 6MP up to 13 days. The castration-induced involution of the VP was accompanied by a reduction in serum T and an increase in serum luteinizing hormone (LH). 6MP had no effect on T and LH serum levels but reduced the DHT content within the VP by 64%. Our results indicate that the structure and secretory acid phosphatase activity of the VP are less sensitive to changes in the ratio of T:DHT than is cell proliferation. Thus, the relative amounts of DHT and T within the VP may prove to be more significant than the absolute amount of either androgen in controlling prostate growth or its attendant neoplasms. 相似文献
5.
Aim There has been considerable debate about pre‐settlement stand structures in temperate woodlands in south‐eastern Australia. Traditional histories assumed massive tree losses across the region, whereas a number of recent histories propose that woodlands were originally open and trees regenerated densely after settlement. To reconcile these conflicting models, we gathered quantitative data on pre‐settlement stand structures in Eucalyptus–Callitris woodlands in central New South Wales Australia, including: (1) tree density, composition, basal area and canopy cover at the time of European settlement; and (2) post‐settlement changes in these attributes. Location Woodlands dominated by Eucalyptus species and Callitris glaucophylla, which originally occupied approximately 100,000 km2 in central New South Wales, Australia. Methods We recorded all evidence of pre‐settlement trees, including stumps, stags and veteran trees, from 39 relatively undisturbed 1‐ha stands within 16 State Forests evenly distributed across the region. Current trees were recorded in a nested 900 m2 quadrat at each site. Allometric relationships were used to estimate girth over bark at breast height, tree basal area, and crown diameter from the girth of cut stumps. A post‐settlement disturbance index was developed to assess correlations between post‐settlement disturbance and attributes of pre‐settlement stands. Results The densities of all large trees (> 60 cm girth over bark at breast height) were significantly greater in current stands than at the time of European settlement (198 vs. 39 trees ha?1). Pre‐settlement and current stands did not differ in basal area. However, the proportional representation of Eucalyptus and Callitris changed completely. At the time of settlement, stands were dominated by Eucalyptus (78% of basal area), whereas current stands are dominated by Callitris (74%). On average, Eucalyptus afforded 83% of crown cover at the time of settlement. Moreover, the estimated density, basal area and crown cover of Eucalyptus at the time of settlement were significantly negatively correlated with post‐settlement disturbance, which suggests that these results underestimate pre‐settlement Eucalyptus representation in the most disturbed stands. Main conclusions These results incorporate elements of traditional and recent vegetation histories. Since European settlement, State Forests have been transformed from Eucalyptus to Callitris dominance as a result of the widespread clearance of pre‐settlement Eucalyptus and dense post‐settlement recruitment of Callitris. Tree densities did increase greatly after European settlement, but most stands were much denser at the time of settlement than recent histories suggest. The original degree of dominance by Eucalyptus was unexpected, and has been consistently underestimated in the past. This study has greatly refined our understanding of post‐settlement changes in woodland stand structures, and will strengthen the foundation for management policies that incorporate historical benchmarks of landscape vegetation changes. 相似文献
6.
There is increasing evidence for beneficial effects of early DMARD (disease-modifying antirheumatic drug) therapy over delayed
treatment in patients who present with arthritis of recent onset. However, no universal consensus exists concerning the choice
of initial drug or whether single drugs or combinations should be given as initial treatments. Recent studies have focused
on the benefits of various strategies in which treatments were tailored to achieve low levels of disease activity, as assessed
using validated response criteria. These studies demonstrated superiority of 'aggressive' over 'conventional' approaches.
Whether the inclusion of tumour necrosis factor antagonists or other biologic targeted therapies in such strategies confers
additional benefits in terms of improved long-term outcomes must be clarified by further studies. Assessment of risks in the
individual patient, allowing individual 'tailoring' of the initial treatment, would be desirable. 相似文献
7.
Nine white-rot fungal strains were screened for biodecolourization of brilliant green, cresol red, crystal violet, congo red and orange II. Dichomitus squalens, Phlebia fascicularia and P. floridensis decolourized all of the dyes on solid agar medium and possessed better decolourization ability than Phanerochaete chrysosporium when tested in nitrogen-limited broth medium. Journal of Industrial Microbiology & Biotechnology (2002) 28, 201–203 DOI: 10.1038/sj/jim/7000222 Received 12 July 2001/ Accepted in revised form 22 October 2001 相似文献
8.
The property of oxygen transport function was investigated in blood which had been stored in solutions of glugizir and zitroglucophosphate and in erythrocyte concentrates gained from it on the noughth, 7th, 14th und 21st day of storage at -4 +/- 2 degrees C. The parameters of the oxygen binding function (oxygen content of erythrocytes, half time of haemoglobin saturation with oxygen, concentration of organic phosphate [2.3 diphosphoglycerate and adenosine triphosphate] and those of inorganic phosphorus were determined in erythrocytes. During storage for more than 21 days no significant differences could be detected in the property of oxygen transfer between erythrocytes of stored blood and erythrocyte concentrate, with the values for storing in zitroglucophosphate being somewhat higher. Problems of applying all components of donor blood efficiently are discussed. In performing an adequate haemotherapy with blood components the importance of a functional condition of erythrocytes and oxygen balance in the organism of the receiver should be considered. The necessity of transfusing erythrocyte concentrate in the therapy of anaemias of different genesis is emphasized and the differences in applying concentrates in different plasma solutions are referred to. By transfusing concentrates the effectiveness of hemotherapy are elevated and the rate of complications and side-effects of whole blood are diminished. 相似文献
9.
Active and passive cation transport and L antigen hertogeneity in low potassium sheep red cells
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Several lines of experimental evidence are presented suggesting that the L antigens in low potassium (LK) sheep red cells are associated with separate Na(+)K(+) pump flux is distinct from the action of anti-L(l) on K(+) leak flux, implying that K(+) leak transport sites may not be converted into active pumps by the L antiserum. Treatment of LK red cells with trypsin completely abolished both the stimulation of K(+) pump flux and the enhancement of the rate of ouabain binding brought about by anti- L. That this effect is due to a total destruction of the L(p) determinant associated with the LK pump was evident from the complete failure of anti-L(p) to bind to trypsinized LK red cells. The L(p) antigen can be effectively protected against the trypsin attack by prior incubation with anti-L, indicating that the sites for antibody binding and trypsin action may be closely adjacent at the structural level. Trypsin treatment, however, did not interfere with anti-L(l) reducing ouabain insensitive K(+) leak influx, nor did it prevent binding of anti-L(ly), the hemolytically active L antibody which is probably identical with anti-L(l). The functional independence of the L(p) and L(l) sites was documented by the observation that anti-L(l) still reduced K(+) leak influx in LK cells with experimentally induced high potassium concentrations, at which K(+) pump flux is fully suppressed, whether or not anti-L(p) was binding to the L(p) antigen associated with the LK pump. 相似文献
10.
The molecular evolution of mammalian Y-linked DNA sequences is of special
interest because of their unique mode of inheritance: most Y- linked
sequences are clonally inherited from father to son. Here we investigate
the use of Y-linked sequences for phylogenetic inference. We describe a
comparative analysis of a 515-bp region from the male sex- determining
locus, Sry, in 22 murine rodents (subfamily Murinae, family Muridae),
including representatives from nine species of Mus, and from two additional
murine genera--Mastomys and Hylomyscus. Percent sequence divergence was
< 0.01% for comparisons between populations within a species and was
0.19%-8.16% for comparisons between species. Our phylogenetic analysis of
12 murine taxa resulted in a single most- parsimonius tree that is highly
concordant with phylogenies based on mitochondrial DNA and allozymes. A
total evidence tree based on the combined data from Sry, mitochondrial DNA,
and allozymes supports (1) the monophyly of the subgenus Mus, (2) its
division into a Palearctic group (M. musculus, M. domesticus, M.
spicilegus, M. Macedonicus, and M. spretus) and an Oriental group (M.
cookii++, M. cervicolor, and M. caroli), and (3) sister-group relationships
between M. spicilegus and M. macedonicus and between M. cookii and M.
cervicolor. We argue that Y- chromosome DNA sequences represent a valuable
new source of characters for phylogenetic inference.
相似文献