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排序方式: 共有2118条查询结果,搜索用时 15 毫秒
21.
J L Broers S M Jensen W D Travis H Pass J A Whitsett G Singh S L Katyal A F Gazdar J D Minna R I Linnoila 《Laboratory investigation; a journal of technical methods and pathology》1992,66(3):337-346
Two markers for the progenitor cells of peripheral airways and their tumors are the 10 kilodalton (kd) Clara cell protein and the major surfactant associated protein-A (SP-A). We used the RNA-RNA in situ hybridization technique to study expression of the genes encoding these proteins at the cellular level in 19 pairs of non-neoplastic and neoplastic tissues from resected human lungs. Our results show that in non-neoplastic lung tissue, the Clara 10 kd protein gene was expressed in nonciliated cells of both bronchial and bronchiolar epithelium, indicating that, in contrast to previous assumptions, cells with Clara cell-like differentiation in humans may not be restricted to bronchiolar cells. The incidence of Clara 10 kd protein gene expression, as detected in lung carcinomas (1 out of 19 cases positive) was less than expected based on previous ultrastructural reports. The SP-A gene was strongly expressed in normal alveolar type II cells in non-neoplastic lung and, at higher levels, in hyperplastic cells. In addition, SP-A mRNA expression was observed in scattered bronchial and bronchiolar epithelial cells in 40% of the airways examined. Five out of 17 lung tumors, all of which were adenocarcinomas, were positive for SP-A expression, albeit generally less intense than type II cells. This expression was seen in carcinomas with papillolepidic as well as solid and glandular growth patterns. Our findings provide new insights into the peripheral airway cell differentiation. 相似文献
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23.
S L Spitalnik P F Spitalnik C Dubois J Mulshine J L Magnani F Cuttitta C I Civin J D Minna V Ginsburg 《Cancer research》1986,46(9):4751-4755
Several mouse monoclonal antibodies which recognize carbohydrate sequences distinguish between different types of human lung cancer immunohistologically. These antibodies bind to glycolipid antigens produced by the cancer cells. When these glycolipids are separated by thin-layer chromatography, immunostaining of the chromatograms yields complex patterns of antigen-positive bands. To determine whether glycolipid patterns are useful in the classification of lung cancer, 16 human lung cancer cell lines comprising the major histological types of primary lung cancer were studied. Neutral glycolipids and gangliosides were isolated and separated by thin-layer chromatography. Six anti-carbohydrate antibodies which recognize structurally related antigens were used for immunostaining. Neuraminidase treatment of the chromatograms was used to detect "cryptic" sialylated antigens. All the cell lines were unique with regard to the type, amount, and chromatography pattern of the glycolipid antigens produced. Small cell lung cancer cell lines synthesized the greatest variety of antigens, whereas cell lines with large cell cytology synthesized the least. Interestingly, there was an inverse relationship between expression of some glycolipid antigens and DNA amplification of the c-myc oncogene. This suggests that enhanced c-myc expression may influence the types of glycolipids expressed at the surface of lung tumor cells. 相似文献
24.
Mohan Srivarshini Cherukupalli Walcott-Sapp Sarah Lee Minna K. Srour Marissa K. Kim Sungjin Amersi Farin F. Giuliano Armando E. Chung Alice P. 《Annals of surgical oncology》2021,28(11):5907-5917
Annals of Surgical Oncology - Biomarker changes in patients with residual disease (RD) after neoadjuvant systemic therapy (NAT) have unclear consequences. This study examined the prevalence of... 相似文献
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The bioavailability and pharmacodynamic bioequivalence of a conventional and an experimental sustained-release formulation of 100 mg metoprolol tartrate were studied in a randomised cross-over study in seven healthy volunteers by assessing over 24 h the plasma kinetics of R,S-metoprolol, its 1-adrenoceptor binding component, and by determining the extent to which the active drug moiety in plasma occupied rabbit lung 1-and rat reticulocyte 2-adrenoceptors.The formulations differed markedly in their kinetic characteristics: the peak plasma concentration (Cmax) of R,S-metoprolol after administration of the conventional formulation was 140 ng·ml–1, (n=7) and it was approximately one-third of that after the sustained-release formulation, 49 ng·ml–1, (n=6); the AUC0–24 h-values for the formulations were 700 and 310 ng·h·ml–1, respectively. The Cmax for the 1-adrenoceptor binding component of metoprolol was 180 ng·ml–1 (n=7) after administration of the conventional, and 74 ng·ml–1 after administration of the sustained-release formulation. The corresponding AUC0–24 h-values for the receptor binding component were 920 and 470 ng·h·ml–1 (n=7).Thus, the kinetic differences between R,S-metoprolol and the 1-receptor binding component were considerable and they were affected by the type of formulation. In general, after administration of the sustained-release formulation, the percentage 1- and 2-adrenoceptor occupancy of metoprolol in plasma was 5–15% less than after administration of the conventional formulation. At 0.5–1.5 h after drug intake the average 1-adrenoceptor occupancy of the conventional formulation varied between 80–90% and that of the sustained release formulation between 20–76%. At these times the differences in receptor occupancy were significant; at 0.5–2 h after drug intake the average 2-adrenoceptor occupancy of the conventional formulation varied from 20–30%, and that of the sustained-release formulation was 2–17%. At other times the difference in receptor occupancy between the formulations was not significant.The results demonstrate that plasma concentration-kinetics were more discriminating than -adrenoceptor-binding in analysing bioequivalence. It was possible to determine the bioavailability of the active ingredient of metoprolol and to study pharmacodynamic bioequivalence by using receptor binding assays. 相似文献
27.
Striatal dopamine transporter density in major depression 总被引:4,自引:0,他引:4
Teijamari Laasonen-Balk Jyrki Kuikka Heimo Viinamäki Minna Husso-Saastamoinen Johannes Lehtonen Jari Tiihonen 《Psychopharmacology》1999,144(3):282-285
Rationale: There are no previous data available regarding [123I]β-CIT binding to the dopamine transporter sites in the basal ganglia in depressed patients. Objective: The present study tested the hypothesis that the brain DAT density in depressed patients is lower than that in matched healthy
controls. Methods: Fifteen drug-naive outpatients with major depression and 18 healthy controls were investigated using single photon emission
computerized tomography (SPECT) with a high-affinity dopamine transporter specific radioligand, 123I-labeled β-CIT (2β-carbomethoxy-3β-(4-iodophenyl)-tropane). Results: We found a significantly higher [123I]β-CIT uptake in both sides of the basal ganglia in patients with major depression than in the controls (Mann-Whitney U-test, P = 0.002 on the right and P = 0.003 on the left). Conclusions: The radioligand uptake reflecting the DAT density was significantly higher among the patients than in the controls. This
finding is unexpected, since it is generally believed that monoaminergic neurotransmission is lower in depression, and therefore
it could be assumed that a reduction in dopamine transmission would lead to secondary down-regulation of DAT density. However,
it is possible that up-regulation of the DAT may be the primary alteration, which leads to lower intrasynaptic dopamine concentration
and to lower dopamine neural transmission.
Received: 20 October 1998/Final version: 25 January 1999 相似文献
28.
良性肺结节HRCT的影像特征 总被引:2,自引:0,他引:2
目的:用HRCT评价良性肺结节。方法:35例经手术病理或临床治愈证实的良性肺结节行HRCT扫描,观察其CT表现。结果:18例结核瘤中15例呈圆形或椭圆形,有长、短毛刺及环蛋壳状钙化者分别为13和14例,10例周围有纤维条索影或卫星播散病灶,7例增强扫描4例呈无强化,3例呈典型的包膜样强化。9例炎性假瘤均发生在两肺上叶前段或下叶基底段,6例结节呈圆形或类圆形,边缘可见长毛刺和胸膜凹陷征,3例周边可见斑片影及血管集束征,7例增强扫描6例呈良性肺结节的动态强化。3例错构瘤2例检出结节边缘砂粒样钙化和中央脂肪密度。2例肺脓肿均表现为圆形或类圆形中央低密度结节,增强扫描呈典型的周边环状强化。1例硬化性血管瘤周围可见受压小血管。1例肺霉菌球呈不规则形,有长毛刺及多个小空腔,周围有血管集束征及胸膜凹陷征。1例纤维瘤呈圆形,边缘光滑,密度均匀。结论:常见及少见良性肺结节进行HRCT扫描有助其定性诊断。 相似文献
29.
Interlaboratory comparison of HER-2 oncogene amplification as detected by chromogenic and fluorescence in situ hybridization. 总被引:5,自引:0,他引:5
Jorma Isola Minna Tanner Amanda Forsyth Timothy G Cooke Amanda D Watters John M S Bartlett 《Clinical cancer research》2004,10(14):4793-4798
PURPOSE: Chromogenic in situ hybridization (CISH) is a new modification of the fluorescence in situ hybridization (FISH) technique for detection of oncogene amplification in archival tumor samples. In CISH, the oncogene probe is detected using a peroxidase reaction, allowing use of transmitted light microscopy. We compared detection of HER-2/neu amplification by CISH with a Food and Drug Administration-approved two-color FISH test in an interlaboratory setting. EXPERIMENTAL DESIGN: Formalin-fixed paraffin-embedded tumor samples from 197 breast cancers were analyzed for HER-2 amplification by CISH. Two-color FISH (PathVysion) CISH of 17 centromere was done if the observer considered it necessary to ascertain amplification status in tumors with borderline HER-2 CISH copy numbers. RESULTS: Paired CISH/FISH results were available from 192 (97%) of 197 cases, no clear difference in success rates of either method was observed. Centromere 17 CISH was considered necessary in seven tumors. CISH and two-color FISH results were concordant in 180 cases (93.8%). There were 92 and 88 tumors found HER-2 amplified and nonamplified, respectively, by both methods. Eight tumors were amplified by CISH but not by FISH, and four tumors exhibited the opposite condition (kappa coefficient 0.875). In 7 of 12 cases differences between the two methods could have related to a lack of CISH chromosome 17 information. The remaining cases were explained by difficult histology (ductal carcinoma in situ, poor representativity, dense lymphocytic infiltration, or intratumoral heterogeneity). CONCLUSIONS: These results indicate that CISH could provide an accurate and practical alternative to FISH for clinical diagnosis of HER-2/neu oncogene amplification in archival formalin-fixed breast cancer samples. 相似文献
30.
Asha Padar Ubaradka G Sathyanarayana Makoto Suzuki Riichiroh Maruyama Jer-Tsong Hsieh Eugene P Frenkel John D Minna Adi F Gazdar 《Clinical cancer research》2003,9(13):4730-4734
PURPOSE: Loss or abnormal expression of Cyclin D2, a crucial cell cycle-regulatory gene, has been described in human cancers; however, data for prostate tumors are lacking. We investigated the epigenetic silencing of Cyclin D2 gene in prostate cancers and correlated the data with clinicopathological features. EXPERIMENTAL DESIGN: Cyclin D2 promoter methylation was analyzed in 101 prostate cancer samples by methylation-specific PCR. In addition, we analyzed 32 nonmalignant prostate tissue samples, which included 24 samples of benign disease, benign prostatic hypertrophy, or prostatitis and 7 normal tissues adjacent to cancer. The methylation status of Cyclin D2 was correlated with the methylation of nine other tumor suppressor genes published previously from our laboratory on the same set of samples (R. Maruyama et al., Clin. Cancer Res., 8: 514-519, 2002). The methylation index was determined as a reflection of the methylated fraction of the genes examined. RESULTS: The frequency of methylation of Cyclin D2 promoter was significantly higher in prostate cancers (32%) than in nonmalignant prostate tissues (6%; P = 0.004), and it was not age related. Aberrant methylation was present at insignificant levels in peripheral blood lymphocytes (8%). We also compared methylation of cyclin D2 with methylation of nine tumor suppressor genes [published previously from our laboratory (R. Maruyama et al., Clin. Cancer Res., 8: 514-519, 2002)] studied in the same set of samples. The concordances between methylation of Cyclin D2 and the methylation of RARbeta, GSTP1, CDH13, RASSF1A, and APC were statistically significant, whereas methylation of P16, DAPK, FHIT, and CDH1 were not significant. The differences in methylation index between malignant and nonmalignant tissues for all 10 genes were statistically significant (P < 0.0001). Among clinicopathological correlations, the high Gleason score group had significantly greater methylation frequency of Cyclin D2 (42%; P = 0.004). Although the high preoperative serum prostate-specific antigen (PSA) group did not have significantly greater methylation frequency, methylation of Cyclin D2 had higher mean PSA value. Also, the prostate cancers in the high Gleason score group had high mean values of PSA. CONCLUSIONS: Our results indicate that methylation of Cyclin D2 in prostate cancers correlates with clinicopathological features of poor prognosis. These findings are of biological and potential clinical importance. 相似文献