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排序方式: 共有2597条查询结果,搜索用时 15 毫秒
1.
Sarah Gilgunn Keefe Murphy Henning Stckmann Paul J. Conroy T. Brendan Murphy R. William Watson Richard J. OKennedy Pauline M. Rudd Radka Saldova 《International journal of molecular sciences》2020,21(23)
The diagnosis and treatment of prostate cancer (PCa) is a major health-care concern worldwide. This cancer can manifest itself in many distinct forms and the transition from clinically indolent PCa to the more invasive aggressive form remains poorly understood. It is now universally accepted that glycan expression patterns change with the cellular modifications that accompany the onset of tumorigenesis. The aim of this study was to investigate if differential glycosylation patterns could distinguish between indolent, significant, and aggressive PCa. Whole serum N-glycan profiling was carried out on 117 prostate cancer patients’ serum using our automated, high-throughput analysis platform for glycan-profiling which utilizes ultra-performance liquid chromatography (UPLC) to obtain high resolution separation of N-linked glycans released from the serum glycoproteins. We observed increases in hybrid, oligomannose, and biantennary digalactosylated monosialylated glycans (M5A1G1S1, M8, and A2G2S1), bisecting glycans (A2B, A2(6)BG1) and monoantennary glycans (A1), and decreases in triantennary trigalactosylated trisialylated glycans with and without core fucose (A3G3S3 and FA3G3S3) with PCa progression from indolent through significant and aggressive disease. These changes give us an insight into the disease pathogenesis and identify potential biomarkers for monitoring the PCa progression, however these need further confirmation studies. 相似文献
2.
GA Masters AM Mauer PC Hoffman D Wyka BL Samuels SA Krauss S Watson H Golomb EE Vokes 《Canadian Metallurgical Quarterly》1998,9(6):677-680
PURPOSE: We designed a phase I-II trial of three active agents, paclitaxel, ifosfamide, and vinorelbine, in advanced non-small-cell lung cancer (NSCLC) to: 1) define the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) of paclitaxel with filgrastim (G-CSF) support; and 2) determine the overall response rate and median survival of patients treated on this regimen. PATIENTS AND METHODS: We treated cohorts of patients with stage IIIB or IV NSCLC with ifosfamide 1.2-1.6 g/m2/day x 3 and vinorelbine 20-25 mg/m2/day x 3 and escalating doses of paclitaxel at 100-175 mg/m2 on day 2 with G-CSF support on a 21-day cycle. One prior experimental single-agent chemotherapy regimen was allowed. RESULTS: Fifty-six patients, were enrolled on this trial: 27 on the phase I portion of the study and an additional 29 at the recommended phase II dose (RPTD). Thirteen patients had received prior chemotherapy. Paclitaxel doses of 175 mg/m2 and 150 mg/m2 produced dose-limiting myelosuppression, and the RPTD was determined to be paclitaxel 135 mg/m2 with ifosfamide 1.2 g/m2/day on days 1-3 and vinorelbine 20 mg/m2/ day on days 1-3 with G-CSF support. The overall response rate was 18%, with a median survival of 6.1 months. Six of 35 patients (17%) treated at the RPTD achieved a partial response to therapy. Grade IV neutropenia was observed in 19 of 35 patients at this dose, with eight patients suffering febrile neutropenia. CONCLUSIONS: This non-cisplatin-containing three-drug regimen has substantial toxicity and low activity in advanced NSCLC, and does not seem to improve on prior regimens. It is unclear whether the lack of efficacy relates to an antagonistic reaction between the specific drugs, administration schedule, or to subtherapeutic doses of the individual agents. 相似文献
3.
14 medicated hypertensive, 15 nonmedicated mild hypertensive, 39 normotensive, and 13 hypotensive adults participated in a 1–2 hr laboratory experiment that assessed each S's symptoms, moods, and estimates of systolic blood pressure (SBP) relative to actual SBP levels. Several self-reports and autonomic measures were collected during and after each of 22 tasks. Within-S correlations indicated that all Ss could estimate SBP at levels greater than chance. Further, 68% of the Ss evidenced at least 1 significant symptom–SBP correlation. Although medicated hypertensives believed they could estimate their BP more accurately than other groups, they were actually no more accurate than the other Ss. They also evidenced far fewer empirically derived symptom–SBP and emotion–SBP correlations than any other group. Overall, blood pressure (BP) beliefs were largely inaccurate. If these erroneous beliefs can be eliminated, Ss may be able to estimate BP fluctuations more accurately. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
For users of an executive information system (EIS), the EIS interface is the system and is crucial to the EIS's success. These guidelines for designing EIS interfaces are based on studies of actual EIS interfaces that meet the unique information needs of executives. 相似文献
5.
Many current implementations of protocols such as the Transmission Control Protocol/Internet Protocol (TCP/IP) are inefficient because data are often accessed more frequently than necessary. Three techniques that reduce the need for memory bandwidth are proposed. The techniques are copy-on-write, page remapping, and single-copy. Afterburner, a network-independent card that provides the services that are necessary for a single-copy protocol stack, is described. The card has 1 MByte of local buffers and provides a simple interface to a variety of network link adapters, including HIPPI and asynchronous transfer mode (ATM). Afterburner can support transfers to and from the link adapter card at rates up to 1 Gbit/s. An implementation of TCP/IP that uses the features provided by Afterburner to reduce the movement of data to a single copy is discussed. Measurements of the end-to-end performance of Afterburner and the single-copy implementation of TCP/IP are presented 相似文献
6.
The mass childhood immunization programme has traditionally been viewed as a safe and effective preventative measure by health promoters, primary health care professionals and governments. This consensus has meant that immunization has rarely been viewed as ethically problematic. A number of recent changes in the context of the delivery of health care, particularly the emphasis on consumerism and the effect of the marketization of services, makes timely an examination of ethical, social and political issues. This article examines four main grounds for problematizing the mass childhood immunization programme. These are: clinical research evidence about the safety and efficacy of vaccines; the masking of wider social and political determinants of ill health; the contradictory strictures about collective and individual rights in relation to immunization; and the uniqueness of childhood immunization as a physical intrusion into a healthy body. The implications of these ethical issues are discussed in relation to informed consent and the need for a 'greenfield' review that includes the views of dissenting parents, lawyers and moral philosophers, as well as health professionals. 相似文献
7.
LT Seery DR Schoenberg ME Canning AS Whitehead 《Canadian Metallurgical Quarterly》1994,150(2):331-333
LY171883, a peroxisome proliferator and leukotriene D4-antagonist, induced a statistically significant increase in the number of hepatic lesions in B6C3F1 female mice in a 2 year oncogenicity study at dietary doses of 0.0225% and 0.075%. The mutation frequency and spectrum of the 61st codon of H-ras was determined for 64 independent, archived lesions from the LY171883 2 year oncogenicity study using the polymerase chain reaction (PCR), allele specific oligo hybridization (ASO) and DNA sequencing. Results showed 41 (64%) of these lesions had mutations at the 61st codon (16/21 hepatocellular carcinomas, 4/10 hepatocellular adenomas, 19/26 focal hepatocellular hyperplasias and 2/7 focal hepatocellular atypia). These mutations consisted of 18 C-A transversions, 16 A-G transitions and seven A-T transversions. Compared to the mutation frequency for spontaneously occurring archival B6C3F1 hepatic lesions (41%), the frequency of LY171883 lesions (64%) was significantly higher (P < 0.01). The frequencies of H-ras 61st codon mutations among the LY171883 lesion types (hepatocellular carcinomas 76%, hepatocellular adenomas 40%, focal hepatocellular hyperplasias 73% and hepatocellular atypia 29%) were also significantly different (P = 0.035). In contrast, spontaneous lesions showed no statistical difference in the frequencies of mutation among lesion types (P > 0.5). The mutation spectrum of the LY171883 lesions was not significantly different from the spontaneous spectra. It may be concluded that based on the similarity in mutation spectrum and the increase in mutation frequency, LY171883 may selectively promote spontaneous hepatic lesions containing H-ras 61st codon mutations. In addition, the difference in mutation frequency among lesion types does not support a linear progression of all LY171883 lesions through focal atypia, focal hepatocellular hyperplasias, hepatocellular adenomas and hepatocellular carcinomas. 相似文献
8.
JH Meador-Woodruff KY Little SP Damask A Mansour SJ Watson 《Canadian Metallurgical Quarterly》1993,34(6):348-355
The effects of chronic cocaine exposure on dopamine D1 and D2 receptor gene expression in the human brain were studied in postmortem samples from chronic cocaine abusing and matched control subjects. Using in situ hybridization of receptor autoradiography to examine messenger ribonucleic acid (RNA) and binding sites, respectively, neither D1 nor D2 receptor expression was found to be changed in the nucleus accumbens, caudate, putamen, or substantia nigra of the cocaine-exposed subjects. Although chronic cocaine exposure can produce alterations in dopaminergic neurotransmission, sustained compensatory changes in dopamine receptor expression do not appear to occur in the human. 相似文献
9.
R. Watson 《Measurement》1994,13(4):267-271
The instrumentation described in this paper is designed to provide a relatively cheap and simple method of recording the changing water level during the operation of a laboratory surge tank. The method detects the passage of the water surface past a number of pairs of electrodes fitted into the side of the surge tank. One of each pair is supplied with a low D.C. voltage, so that when the pair is immersed in water, a small current flows. This signal is amplified and encoded before being used by a VELA datalogger acting as a timing device. The data is later transferred to a microcomputer for presentation in graphical and printed form. The method copes accurately both with the initial rapid large change in water level and the subsequent slowly decaying oscillations. It can also be used for automatic calibration of other methods of recording changing water levels. 相似文献
10.