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31.
The objective of the present study was to compare two configurations of the hepatocyte model namely suspensions (SH) and conventional primary cultures (CPC) for their ability to predict the hepatic clearance in vivo in the rat and, to investigate the impact of serum on the prediction accuracy. The metabolic competences of several cytochrome P450 isoenzymes were investigated both in CPC and SH in the presence or absence of serum. Under the same conditions, the in vitro intrinsic clearance of six test compounds metabolised by a variety of phase I and phase II enzymes (antipyrine, RO-X, mibefradil, midazolam, naloxone and oxazepam) were derived from Vmax/Km scaled up to the corresponding in vivo hepatic metabolic clearance. CYP activities were shown to be stable in both CPC and SH for up to 6 h of incubation, except for the CYP 3A1 activity that decreased in CPC even in the presence of serum. Moreover, the clearances predicted from SH in the presence of serum were closer to the in vivo values than those obtained from CPC. SH represent a convenient model to assess the hepatic metabolism of xenobiotics, the presence of serum in the incubation medium significantly improved in several instances the quality of the predictions.  相似文献   
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To investigate the possibility that the epidermal growth factor (EGF) receptor functions as an oncogene product, we have determined the levels of EGF receptor protein and RNA in a variety of malignant and normal human cells, using a specific polyclonal antibody to the EGF receptor and a cDNA clone (plasmid pE7) that encodes the EGF receptor, respectively. Besides A431 epidermoid carcinoma cells, which are known to make large amounts of EGF receptor, cell lines from two ovarian cancers, two cervical cancers, and one kidney cancer were found to contain substantial amounts of receptor protein (11-22% of A431). Normal human fibroblasts (Detroit 551), a human lymphocyte line (IM-9), and a leukemic lymphocyte line (CEM) contained low or undetectable levels of EGF receptor. RNA blot analysis showed that among the human cell lines examined the levels of a 10- and a 5.6-kilobase species of pE7-specific RNA generally correlated with the amount of the EGF receptor protein. Genomic DNA blot analysis revealed that except for A431 none of these cell lines expressing high levels of EGF receptor protein possessed amplified receptor gene sequences. A431 cells are known to secrete a truncated form of the EGF receptor. An abundant 2.9-kilobase RNA is found only in A431 cells; it could encode the truncated form of the EGF receptor.  相似文献   
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Background:

There is currently no standard second-line treatment for metastatic pancreatic adenocarcinoma (MPA), and progression-free survival is consistently <4 months in this setting. The aim of this study was to evaluate the efficacy and tolerability of Nab-paclitaxel plus gemcitabine (A+G) after Folfirinox failure in MPA.

Methods:

From February 2013 to July 2014, all consecutive patients treated with A+G for histologically proven MPA after Folfirinox failure were prospectively enrolled in 12 French centres. A+G was delivered as described in the MPACT trial, until disease progression, patient refusal or unacceptable toxicity.

Results:

Fifty-seven patients were treated with Nab-paclitaxel plus gemcitabine, for a median of 4 cycles (range 1–12). The disease control rate was 58%, with a 17.5% objective response rate. Median overall survival (OS) was 8.8 months (95% CI: 6.2–9.7) and median progression-free survival was 5.1 months (95% CI: 3.2–6.2). Since the start of first-line chemotherapy, median OS was 18 months (95% CI: 16–21). No toxic deaths occurred. Grade 3–4 toxicities were reported in 40% of patients, consisting of neutropenia (12.5%), neurotoxicity (12.5%), asthenia (9%) and thrombocytopenia (6.5%).

Conclusions:

A+G seems to be effective, with a manageable toxicity profile, after Folfirinox failure in patients with MPA.  相似文献   
35.
Many individuals are motivated to improve their physical activity levels but often fail to act on their good intention. This study examines the roles of planning and self-efficacy in the prediction of physical activity. A total of 290 participants (77% women, mean age = 41.9 years) were surveyed three times. Intentions, planning, and physical activity were specified as a mediator chain. Results reveal that intentions were partly translated into physical activity by planning. Self-efficacy moderated this mediation, reflected by a planning × self-efficacy interaction (p < .05) on physical activity accounting for 16% of the variance in behavior. If a person is self-efficacious, planning seems more likely to be translated into physical activity.  相似文献   
36.
Although several reports suggest that bee venom may be an effective treatment for patients with multiple sclerosis (MS), patients may be subjected to real risks of serious allergic reactions as well as emotional and economic costs. This study was conducted to evaluate the safety of bee venom extract as a possible treatment for patients with progressive forms of MS. A total of nine bee venom nonallergic patients with progressive forms of MS, who were 21-55 years of age with no other illnesses, were entered into four groups (A, B, C, and D) on a structured 1-year immunization schedule. Hyperreactivity to bee venom was evaluated by questionnaire, physical examination, and a battery of hematologic, metabolic, and immunologic tests. Responses to therapy were evaluated by questionnaire, functional neurological tests, and changes in measurement of somatosensory-evoked potentials. Although no serious adverse allergic reactions were observed in any of the nine subjects, four experienced worsening of neurological symptoms, requiring termination in the study; this could not be ascribed to side effects of the therapy. Of the remaining five subjects, three felt that the therapy had subjective amelioration of symptoms and two showed objective improvement. Although this preliminary study suggests safety, because of the small numbers studied, there were no definite conclusions regarding efficacy and therefore there was little evidence to support the use of honeybee venom in the treatment of MS. Larger and more carefully conducted multicenter studies will be required to establish efficacy.  相似文献   
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Myelin basic protein (MBP)-reactive T cells have been implicated in the autoimmune pathogenesis of multiple sclerosis (MS). In this study, we examined the cytokine profile of 531 primary MBP-reactive T-cell lines and 72 independently established clones from 32 patients with MS and 18 healthy controls (NS) by using highly sensitive enzyme-linked immunosorbent assays. An increased number of primary T-cell lines producing interferon-γ (IFNγ) and/or interleukin-4 (IL-4) in response to MBP were found in patients with MS compared with controls. No distinct Th1 or Th2 subtypes could be demonstrated among the MBP-reactive clones. IL-4 was more frequently observed among MS-derived clones. Clones derived from MS patients produced increased levels of IL? 2, IL? 4, tumor necrosis factor-α (TNFα), IFNγ, and IL-10, but not IL-6. It is interesting that MBP-reactive T cells from MS patients expressing the disease-associated HLA-DRBI 15 allele produced increased quantities of TNFα, a cytokine suggested to play an important role in inflammation and demyelination. When challenged with either MBP or a bacterial superantigen, the clones expressed similar levels of the proinflammatory cytokine IFNγ. Our study suggests a functional difference in T-cell responses to MBP in patients with MS compared with healthy individuals, and provides further insights into the role of MBP-reactive T cells and their cytokine profile in the inflammatory processes of MS.  相似文献   
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