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51.
从假细锥香茶菜(Rabdosia coetsoides C.Y.Wu)叶分离得到新二萜成分,根据紫外光谱、红外光谱、质谱、核磁共振氢谱及碳谱等分析,推定了化学结构,并经X-射线衍射确证,命名为假细锥甲素。  相似文献   
52.
Epling-Burnette  PK; Wei  S; Blanchard  DK; Spranzi  E; Djeu  JY 《Blood》1993,81(11):3130-3137
Human monocytes express interleukin-2 receptor beta (IL-2R beta) constitutively; however, the function of these receptors has not been fully delineated. We discovered that IL-2R beta directs two biologic activities in human monocytes, the release of granulocyte-macrophage colony-stimulating factor (GM-CSF) and increased susceptibility to lysis by lymphokine-activated killer cells (LAK) cells. Human monocytes were purified from peripheral blood mononuclear cells by plastic adherence and anti-CD2 plus complement lysis. By a 5-hour 51Cr-release assay, monocytes cultured in IL-2 were found to gain increasing susceptibility to LAK cells with time and this effect was dose dependent. Maximal susceptibility was obtained with a 4-day culture in 1,000 U/mL of IL-2. Monocytes were also found to release GM-CSF in response to IL-2 using a CSF-dependent cell line, Mo7e. Because IL-2- induced GM-CSF release coincides with LAK lysis of IL-2-cultured monocytes, we treated monocytes with anti-GM-CSF and anti-IL-2R beta to determine whether GM-CSF release and LAK susceptibility were dependent or independent events. We found that both phenomena were inhibited by either antibody. Therefore, we conclude that IL-2-induced release of GM- CSF is mediated by IL-2R beta, which then acts to modulate the susceptibility of monocytes to lysis by LAK cells.  相似文献   
53.
Clinical Rheumatology - The data concerning the association between dengue viruses (DV) infection and autoimmune diseases (ADs) remain unclear and are scarce. This nationwide population-based...  相似文献   
54.
This study investigated the pharmacokinetics, safety, and tolerability of aliskiren administered alone or in combination with either the loop diuretic furosemide or an oral extended‐release formulation of isosorbide‐5‐mononitrate (ISMN). In separate studies, 22 healthy subjects (ages 18–45 years) received either ISMN 40 mg or furosemide 20 mg once‐daily for 3 days followed by a 3‐day washout. Subjects then received aliskiren 300 mg once‐daily for 7 days followed by combination therapy for 3 days. Pharmacokinetic assessments were taken at regular intervals over 24 h after dosing on the last day of each treatment period. At steady state, aliskiren AUCτ was decreased by 7% (geometric mean ratio [90% CI], 0.93 [0.84, 1.04]), and Cmax by 20% (0.80 [0.65, 0.97]) with furosemide coadministration compared with aliskiren administration alone. Aliskiren coadministration reduced furosemide AUCτ by 28% (0.72 [0.64, 0.81]) and Cmax by 49% (0.51 [0.39, 0.66]) compared with furosemide alone. Coadministration of aliskiren and ISMN was associated with only minor changes in the pharmacokinetic parameters of aliskiren (AUCτ 1.03 [0.90, 1.18]; Cmax 0.94 [0.69, 1.29]) and ISMN (AUCτ 0.88 [0.71, 1.10]; Cmax 0.94 [0.79, 1.13]). Headache and dizziness were the most common adverse events in both studies; dizziness and BP values below normal (SBP <90 and/or DBP <50 mmHg) were more frequent with aliskiren and ISMN coadministration than with either agent alone. Coadministration of aliskiren and ISMN had no clinically relevant effect on either aliskiren or ISMN pharmacokinetics. In conclusion, coadministration of aliskiren and furosemide reduced furosemide exposure and had a minor effect on aliskiren pharmacokinetics. The clinical significance of reduced systemic exposure to furosemide during coadministration of aliskiren is uncertain.  相似文献   
55.
A phase III prospective randomized multicenter study was performed to determine whether quinine could improve the response rate of poor-risk acute leukemias (ALs) to standard chemotherapy including a multidrug resistance (MDR)-related cytotoxic agent. The rationale of the study was based on the negative prognostic value of MDR phenotype in ALs and the ability of quinine to reverse this phenotype both in vitro and ex vivo. Three hundred fifteen patients (median age, 49 years; range, 16 to 65) with relapsed (n = 108) or refractory (n = 32) acute myeloblastic leukemia (AML), relapsed (n = 27) or refractory (n = 9) acute lymphoblastic leukemia (ALL), secondary AL (n = 22) or blastic transformation of myelodysplastic syndrome ([MDS] n = 74) or myeloproliferative syndrome ([MPS] n = 43) were randomly assigned to receive mitoxantrone ([MXN] 12 mg/m2/d, days 2 to 5) and cytarabine ([Ara-C] 1 g/m2/12 h, days 1 to 5) alone or in combination with quinine (30 mg/kg/d, days 1 to 5; continuous intravenous infusion beginning 24 hours before MXN infusion). Side effects of quinine were observed in 56 of 161 quinine-treated patients and disappeared in all but four cases after one or two 20% dose decreases. Sera from quinine-treated patients showed increased MXN uptake in an MDR-positive cell line compared with matched sera obtained before quinine infusion. Quinine induced a significant increase in the incidence of nausea, vomiting, mucositis, and cardiac toxicity. A complete response (CR) was observed in 85 of 161 patients (52.8%) from the quinine-treated group versus 70 of 154 patients (45.5%) in the control group (P = .19). The most important differences between quinine and control group CR rates were observed in patients with refractory AMLs and blastic transformation of MDS and MPS. The CR rate was higher in P-glycoprotein-positive cases, although the difference was not significant. Failure of the regimen due to blastic persistence or blast number increase was higher in the control group (61 of 154 patients) than in the quinine group (45 of 161, P = .04). Early death was observed in eight cases (four in each arm) and death in aplasia in 27 cases (20 in quinine group v seven in control group, P = .01). The significant increase of toxicity in the quinine arm could have masked the clinical benefit of MDR reversion in poor- risk ALs.  相似文献   
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Although the Dexamethasone Suppression Test (DST) plays an important role in psychosomatic research, confounding factors limit the sensitivity and specificity of the DST. The aim of this study was to investigate the relationship between the intensity of daily life stressors and DST results in healthy participants after controlling the confounding factors. The subjects of this study consisted of 75 healthy volunteers. The intensity of daily life events was assessed using the Taiwanese version of the Recent Life Change Questionnaire (RLCQ). Neuroticism was assessed using the Maudsley Personality Inventory (MPI). The Dexamethasone Suppression Test (DST) was also performed. The regression model showed that daily life events (RLCQ score) were correlated significantly with cortisol level on day 1 and D% only in women. This finding implies that daily life events should be considered as an independent variable in women in further studies when the DST is applied.  相似文献   
58.
Toxoplasma gondii infects all warm-blooded animals including humans, causing serious public health problems and great economic loss in the food industry. Commonly used serological tests involve preparation of whole Toxoplasma lysate antigens from tachyzoites which are costly and hazardous. An alternative method for better antigen production involving the prokaryotic expression system was therefore used in this study. Recombinant dense granular protein, GRA2, was successfully cloned, expressed, and purified in Escherichia coli, BL21 (DE3) pLysS. The potential of this purified antigen for diagnosis of human infections was evaluated through western blot analysis against 100 human serum samples. Results showed that the rGRA2 protein has 100 and 61.5 % sensitivity towards acute and chronic infection, respectively, in T. gondii-infected humans, indicating that this protein is useful in differentiating present and past infections. Therefore, it is suitable to be used as a sensitive and specific molecular marker for the serodiagnosis of Toxoplasma infection in both humans and animals.  相似文献   
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