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排序方式: 共有80条查询结果,搜索用时 16 毫秒
1.
2.
DC Chhieng AR Frost S Niwas H Weiss WE Grizzle S Beeken 《Biotechnic & histochemistry》2013,88(1):25-36
Small biopsy samples are used increasingly to assess the biomarker expression for prognostic information and for monitoring therapeutic responses prior to and during neoadjuvant therapy. The issue of intratumor heterogeneity of expression of biomarkers, however, has raised questions about the validity of the assessment of biomarker expression based on limited tissue samples. We examined immunohistochemically the expression of HER-2neu (p185erbB-2), epidermal growth factor receptor (EGFR), Bcl-2, p53, and proliferating cell nuclear antigen (PCNA) in 30 breast carcinomas using archived, paraffin embedded tissue and determined the extent of intratumor heterogeneity. Each section was divided into four randomly oriented discrete regions, each containing a portion of the infiltrating carcinoma. For each tumor, the entire lesion and four regions were analyzed for the expression of these markers. Scores of both membrane and cytoplasmic staining of HER-2neu and EGFR, scores of cytoplasmic staining of Bcl-2, and scores of nuclear staining of both p53 and PCNA were recorded. The intensity of staining and the proportion of immunostained cells were determined. A semiquantitative immunoscore was calculated by determining the sum of the products of the intensity and corresponding proportion of stained tumor cells. We analyzed both invasive (IDC) and in situ (DCIS) carcinomas. The Wilcoxon signed-rank test was used for paired comparisons between overall and regional immunoscores and between overall and regional percentages of stained cells. Spearman's correlation coefficients were used to assess the level of agreement of overall biomarker expression with each of the regions. Generalized linear models were used to assess overall and pair-wise differences in the absolute values of percent changes between overall and regional expression of biomarkers. For IDCs, there were no statistically significant differences in the expression of the biomarkers in terms of either the percentage of cells staining or the immunoscores when comparing the entire tumor with each region except for the lower EGFR expression of arbitrarily selected region 1 and lower p53 expression of region 1 compared to that of the entire tumor section. For DCIS, there were no statistically significant differences in the expression of the biomarkers between the entire tumor and each region except in PCNA of region 2 compared to that of entire tumor section. Positive correlation of immunoscores was observed between the entire tumor and each region as well as across all four regions for IDC. Similar observations were noted with DCIS except for HER-2neu and PCNA. No statistically significant differences were observed in the absolute values of percent changes of biomarker expression between overall and the four regions for both DCIS and IDC. Therefore, no significant intratumor heterogeneity in the expression of HER-2neu, Bcl-2, and PCNA was observed in IDC. Minor regional variations were observed for EGFR and p53 in IDC. Similarly, no significant regional variation in the expression of markers was observed in DCIS except for PCNA. 相似文献
3.
4.
SHARPE WE 《California medicine》1950,73(5):391-393
The virus of human poliomyelitis has been demonstrated in excretions before onset of the disease, during the disease, and in convalescence. It may be confused with different viruses likely to be found in the same sources in clinical conditions resembling poliomyelitis.Immunologic differences between strains of poliomyelitis virus have been detected so that three types are now evident. The distribution of these types and their importance as causes of epidemics are not known. This multiplicity of immunologic types is an important factor in considering immunization of humans. Commercial manufacture of vaccines faces many technical problems. Recently the Coxsackie virus has been demonstrated in humans with a disease closely resembling poliomyelitis. 相似文献
5.
STAPHYLOCOCCI AND MICROCOCCI ASSOCIATED WITH DAIRYING 总被引:6,自引:6,他引:0
6.
P.I. PETERKIN C.F. LANGFORD J.R. CHAMBERS A.N. SHARPE 《Journal of Rapid Methods and Automation in Microbiology》1992,1(3):173-178
An electronic counting system using hydrophobic grid-membrane filters (HGMF) and the HGMF Interpreter was evaluated for its usefulness in enumerating nalidixic acid resistant Salmonella in frozen chicken caeca. Salmonella recovery was equivalent on both Hektoen Enteric and EF-18 agars. However, the color of the Salmonella growth on EF-18 agar was more easily differentiated by the HGMF Interpreter electronic counting system. the study showed that a 4 h resuscitation on a nonselective medium was required in order to maximize the subsequent recovery on Hektoen Enteric agar, though not on EF-18 agar. Using the EF-18 agar as the Salmonella selective medium, a method was established that recorded counts of nalidixic acid resistant Salmonella rapidly and easily in electronic data files, for subsequent retrieval and manipulation. 相似文献
7.
GREGORY D. D. HURST ROSIE G. SHARPE ANGELA H. BROOMFIELD LINDA E. WALKER TAMSIN M. O. MAJERUS ILIA A. ZAKHAROV MICHAEL E. N. MAJERUS 《Ecological Entomology》1995,20(3):230-236
Abstract.
- 1 Sexually transmitted diseases (STDs) have rarely been reported in insects and other invertebrates. The majority of those reported involve organisms where sexual transmission is augmented by either vertical (i.e. inherited) transmission, or horizontal transmission, independent of host sexual activity.
- 2 We here demonstrate the existence of an STD in the coccinellid beetle Adalia bipunctata. This species bears a parasitic mite of the genus Coccipolipus. We show that, like many other podapolipid mites, this mite is transmitted between host individuals at a high rate during copulation. It also appears to be transmitted at a low rate between non-copulating individuals.
- 3 We show that infected female A.bipunctata produced eggs at a reduced rate, and that the eggs produced by infected females have highly decreased viability. However, no effect of infection upon host longevity was observed.
- 4 The results are discussed in relation to the incidences of sexually transmitted disease in invertebrates in general, the causes of disease symptoms, and the importance of this disease in the evolution of A.bipunctata.
8.
Early evolution of metazoan serine/threonine and tyrosine kinases: identification of selected kinases in marine sponges 总被引:14,自引:1,他引:13
The phylum Porifera (sponges) was the first to diverge from the common
ancestor of the Metazoa. In this study, six cDNAs coding for protein-
serine/threonine kinases (PS/TKs) are presented; they have been isolated
from libraries obtained from the demosponges Geodia cydonium and Suberites
domuncula and from the calcareous sponge Sycon raphanus. Sequence
alignments of the catalytic domains revealed that two major families of
PS/TK, the "conventional" (Ca(2+)-dependent) protein kinase C (PKC), the
cPKC subfamily, as well as the "novel" (Ca(2+)- independent) PKC (nPKC),
form two separate clusters. In each cluster, the sequence from S. raphanus
diverges first. To approach the question about the origin of
protein-tyrosine kinases (PTK), which are found only in Metazoa, we
analyzed two additional PS/TKs which have been cloned from S. domuncula:
the stress-responsive protein kinase (KRSvSD) and the
protein-kinase-C-related kinase (PRKvSD). The construction of the
phylogenetic tree, comprising the eight PS/TKs and the PTK cloned
previously from G. cydonium, revealed that the PTK derived from the branch
including the KRSvSD kinase. These data facilitate the first molecular
approach to elucidate the origin of metazoan PTK within the PS/TK
superfamily.
相似文献
9.
A cultured rat ovarian cell line (31 A-F(2)) was used to study the effect of growth factors (epidermal growth factor [EGF] and fibroblast growth factor [FGF]), a survival factor (ovarian growth factor [OGF]), a hormone (insulin), and an iron-binding protein (transferring) on cell proliferation and steroid production under defined culture conditions. EGF and insulin were shown to be mitogenic (half-maximal response at 0.12 nM and 0.11 muM, respectively) for 31A-F(2) cells incubated in serum-free medium. EGF induced up to three doublings in the cell population, whereas insulin induced an average of one cell population doubling. FGF, OGF, and transferrin were found not to have any prominent effect on cell division when incubated individually with 31A-F(2) cells in serum-free medium. However, a combination of EGF, OGF, insulin, and transferrin stimulated cell division to the same approximate extent as cells incubated in the presence of 5 percent fetal calf serum. EGF or insulin did not significantly affect total cell cholesterol levels (relative to cells incubated in serum-free medium) when incubated individually with 31A-F(2) cells. However, cell cholesterol levels were increased by the addition of OGF (250 percent), FGF (370 percent), or a combination of insulin and EGF (320 percent). Progesterone secretion from 31A-F(2) cells was enhanced by EGF (25 percent), FGF (80 percent), and insulin (115 percent). However, the addition of a mitogenic mixture of EGF, OGF, insulin, and transferrin suppressed progesterone secretion 150 percent) below that of control cultures. These studies have permitted us to determine that EGF and insulin are mitogenic factors that are required for the growth of 31A-F(2) cells and that OGF and transferrin are positive cofactors that enhance growth. Also, additional data suggest that cholesterol and progesterone production in 31A-F(2) cells can be regulated by peptide growth factors and the hormone insulin. 相似文献
10.
A MEDIUM FOR THE CULTIVATION OF LACTOBACILLI 总被引:9,自引:0,他引:9
SUMMARY: An improved growth medium for lactobacilli is described. It supports good growth of lactobacilli generally and also is particularly useful for a number of fastidious strains which grow only poorly in other general media. In addition, tomato juice, a highly variable material, is not required. In a slightly modified form, it can also be used as a basal medium for fermentation tests. 相似文献