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排序方式: 共有6239条查询结果,搜索用时 15 毫秒
31.
Maria Antonietta Sabatino Tina Colombo Cristina Geroni Sergio Marchini Massimo Broggini 《Clinical cancer research》2003,9(14):5402-5408
PURPOSE: Brostallicin (PNU-166196) is a alpha-bromoacrylic DNA minor groove binder, currently in clinical evaluation. This drug has the peculiarity of showing enhanced antitumor activity in cells with high glutathione S-transferase (GST)/glutathione content. The purpose of the study was to study multiple combinations of brostallicin with classical anticancer agents. EXPERIMENTAL DESIGN: The cis-dichloro-diammine-platinum (cDDP)/brostallicin combination was tested in the human colon carcinoma (HCT-116) model transplanted in nude mice. Two treatment schedules were tested: cDDP followed by brostallicin 48 h after or brostallicin followed by cDDP. These two schemes were selected from the observation that tumor cells in vitro show an increased activity of GST 48 h after cDDP treatment. The HCT-116 model was used also to test the irinotecan (cPT-11)/brostallicin combination. The effect of brostallicin in combination with doxorubicin (DX) was studied in the i.v. injected murine L1210 leukemia. Three administration schedules were tested. The antitumor activity of brostallicin and Taxotere was tested on the A549 lung cancer xenografts. RESULTS: In line with the increased GST activity observed after treatment with cDDP, the cDDP/brostallicin interaction was sequence-dependent, leading to a more than additive antitumor effect, without additional toxicity, only when cDDP was given before brostallicin. The antitumor effect of CPT-11 was enhanced significantly by brostallicin cotreatment. A more than additive antitumor effect, without additional toxicity, was observed when DX/brostallicin were sequentially administered in L1210-bearing mice. Finally, additivity was observed when brostallicin/Taxotere simultaneous combination was tested. CONCLUSIONS: Although the precise molecular mechanism of interaction between brostallicin and the other tested cytotoxics has not yet been identified, a clear therapeutic gain is observed in preclinical models when brostallicin is combined with anticancer agents such as cDDP, DX, CPT-11, and Taxotere. These results indicate the potential therapeutic value of brostallicin in cancer combination treatment therapy. 相似文献
32.
Herman Nys Sander Welie Tina Garanis-Papadatos Dimitris Ploumpidis 《Health care analysis》2004,12(4):329-337
The discriminatory effects of categorizing psychiatric patients into competent and incompetent, have urged lawyers, philosophers and health care professionals to seek a functional approach to capacity assessment. Dutch and English law have produced some guidelines concerning this issue. So far, most legal systems under investigation have concentrated on alternatives for informed consent by the patient in case of mental incapacity, notably substitute decision-making, intervention of a judge and advance directives. It is hard to judge the way in which the law may further adapt to a more functional assessment of capacity, because the nature of law shows that legal reforms usually take place only when new methods have been accepted by the field. This is not yet the case today. 相似文献
33.
BACKGROUND: Six patients known to have inoperable esophageal carcinoma presented with stridor due to both malignant tracheal stenosis (n = 6) and bilateral vocal cord paralysis. Two patients also had respiratory-digestive fistula. METHODS: Patency was restored by endotracheal stenting plus unilateral cordectomy. Four patients had immediate relief. Two patients required enlargement of the cord incision. One of them declined reoperation and underwent tracheotomy. RESULTS: Stent function was uneventful. There was no dislodgement or mucous impaction. Fistula seal was complete. There was no aspiration through the new-shaped glottic orifice. Peak expiratory flow increased from 24.4% +/- 9.7% predicted normal before to 40.5% +/- 13.7% after the procedure, whereas the dyspnea score decreased from 74.2 +/- 12.7 to 24.2 +/- 14.0. CONCLUSIONS: Restoration of airway continuity in serial laryngotracheal stenoses using a combined approach is a feasible technique in end-stage cancer patients. It effectively relieves respiratory distress and ensures voice preservation. In addition, it may avoid the risks of tracheotomy. 相似文献
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35.
Yue GG Fan JT Lee JK Zeng GZ Ho TW Fung KP Leung PC Tan NH Lau CB 《British journal of pharmacology》2011,164(7):1883-1898
BACKGROUND AND PURPOSE
Anti-angiogenic agents have recently become one of the major adjuvants for cancer therapy. A cyclopeptide, RA-V, has been shown to have anti-tumour activities. Its in vitro anti-angiogenic activities were evaluated in the present study, and the underlying mechanisms were also assessed.EXPERIMENTAL APPROACH
Two endothelial cell lines, human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (HMEC-1), were used. The effects of RA-V on the proliferation, cell cycle phase distribution, migration, tube formation and adhesion were assessed. Western blots and real-time PCR were employed to examine the protein and mRNA expression of relevant molecules.KEY RESULTS
RA-V inhibited HUVEC and HMEC-1 proliferation dose-dependently with IC50 values of 1.42 and 4.0 nM respectively. RA-V inhibited migration and tube formation of endothelial cells as well as adhesion to extracellular matrix proteins. RA-V treatment down-regulated the protein and mRNA expression of matrix metalloproteinase-2. Regarding intracellular signal transduction, RA-V interfered with the activation of ERK1/2 in both cell lines. Furthermore, RA-V significantly decreased the phosphorylation of JNK in HUVEC whereas, in HMEC-1, p38 MAPK was decreased.CONCLUSIONS AND IMPLICATIONS
RA-V exhibited anti-angiogenic activities in HUVEC and HMEC-1 cell lines with changes in function of these endothelial cells. The underlying mechanisms of action involved the ERK1/2 signalling pathway. However, RA-V may regulate different signalling pathways in different endothelial cells. These findings suggest that RA-V has the potential to be further developed as an anti-angiogenic agent. 相似文献36.
Pihl K Sørensen TL Nørgaard-Pedersen B Larsen SO Nguyen TH Krebs L Larsen T Christiansen M 《Prenatal diagnosis》2008,28(3):247-253
OBJECTIVE: To establish the relationship between the first-trimester screening markers [pregnancy-associated plasma protein A (PAPP-A), free human chorionic gonadotrophin-beta (beta-hCG), nuchal translucency (NT)], the Down syndrome (DS) risk estimate, and the adverse outcomes such as low birth weight, small for gestational age (SGA) and pre-term delivery. METHODS: A retrospective cohort study including 1,734 non-selected singleton pregnancies consecutively enrolled into the programme of first-trimester combined screening for DS in a 12-month period at a single centre. Data from the Prenatal Patient Registry in ASTRAIA were combined with the Danish National Newborn Screening Registry and Danish Birth Registry. RESULTS: There was a significant relation between low PAPP-A MoM, low beta-hCG MoM, increased risk estimate for DS and low birth weight and SGA. Low PAPP-A MoM and increased NT showed a significant relation to pre-term and spontaneous pre-term delivery. Low PAPP-A MoM showed a significant relation to early pre-term delivery. CONCLUSION: First-trimester screening markers exhibited a significant relation to low birth weight, SGA and to some extent, to pre-term and early pre-term delivery. The screening performance of individual markers was poor. 相似文献
37.
BACKGROUND: First-trimester maternal serum screening for Down syndrome (DS) can be improved by the use of additional serum markers. We examined whether progesterone (P), synthesized by placenta, might be a first-trimester maternal serum marker for fetal DS. MATERIALS AND METHODS: P was quantified in first-trimester maternal serum from 42 DS, six trisomy 18 and two trisomy 13 pregnancies and 115 controls. Log-regression of P versus gestational age in days was used to convert P concentrations into multiples of the median (MoM). RESULTS: The P concentrations in controls increased with gestational age (p = 9.5 x 10(-7)). The log10MoM P distribution in DS pregnancies was not significantly different from that in controls. However, from day 58-67, the log10MoM P was elevated in DS pregnancies (n = 10) with a mean (SD) of 0.1040 (0.0956), compared to a mean (SD) of - 0.0109 (0.1661) in controls (n = 24) (p = 0.05). Five out of six trisomy 18 and both trisomy 13 pregnancies had a P MoM < 1. CONCLUSION: P is not a useful marker for DS in first trimester, except perhaps in a narrow gestational age window from day 58 to 67. P is a trisomy 18/13 marker. 相似文献
38.
39.
Tomas V. Gonzalez Tiffany M. Sae-Kho Steven I. Robinson Tina J. Hieken Andrew L. Folpe Stephen M. Broski Amy C. Degnim Katrina N. Glazebrook 《Radiology Case Reports》2022,17(10):3624
Radiation-associated angiosarcoma of the breast (RAASB) is a rare and aggressive malignancy occurring after radiation therapy as part of breast cancer treatment. RAASB usually presents several years after prior radiation and typically involves the skin with or without involvement of the parenchyma. Most RAASB are detected as cutaneous changes on physical exam. Herein, we present a unique case of a clinically occult RAASB diagnosed as non-mass enhancement on annual surveillance breast MRI. 相似文献
40.