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71.
CD40 stimulation can synergize with interleukin (IL)-2 for antitumor responses against mouse metastatic renal cell carcinomas, with coincident increases in tumor-specific CD8+ T-cell responses and dendritic cell numbers in both the spleen and liver. Because CD40 is present on various hematopoietic-derived cells, endothelial cells, and some tumors themselves, this study was performed to determine whether the antitumor effects of CD40 stimulation and IL-2 were primarily mediated by CD40+ hematopoietic-derived cells. Bone marrow chimeras were created by reconstituting lethally irradiated CD40+/+ recipients with bone marrow from CD40-/- or CD40+/+ mice. Chimeric mice were then implanted orthotopically with renal cancer cells, followed by treatment with anti-CD40 agonist monoclonal antibodies and IL-2. Immune parameters of the spleen and liver were assessed after therapy and correlated with antitumor responses. The antitumor effects in the CD40-/- bone marrow transplantation chimeras were almost completely abrogated after treatment, and this shows that hematopoietically derived CD40+ cells are the principal targets for CD40 stimulation in this model. Although both spleen and liver showed reductions in CD8+ T-cell and dendritic cell expansion in the CD40-/- versus CD40+/+ chimeras after therapy, only the liver exhibited no significant increases in either CD8+ T cells or dendritic cells after treatment. CD40 cells on hematopoietic cells are the primary target for anti-CD40 and IL-2 therapy. The results also suggest that the immunologic events in the liver may be more revealing that those in lymphoid organs with regard to critical events related to responses after therapy.  相似文献   
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73.
We describe a novel test-strip immunoassay for quantifying drugs in biological fluids. This enzyme immunochromatographic ("immunograph") method combines many features of the enzyme-channeling homogeneous immunoassay with immunochromatography and capillary migration to provide a non-separation, non-instrumental assay for theophylline in which quantification is based on the spatial distribution of enzyme label rather than on the modulation of enzyme activity. Sample antigen and hapten-enzyme conjugate are combined and moved by capillary action up a paper strip on which specific antibody has been immobilized. After color development, the assay result is evaluated by measuring the height of the colored zone on the test strip. Quantification is not a function of enzyme activity, so the method is relatively insensitive to sample matrix effects, enzyme instability, temperature, and incubation timing. Either whole blood or plasma can be used as sample. Results correlate well with those by established instrumental methods. The simple, rapid (15 min), two-incubation protocol is well suited for on-site testing in non-laboratory environments.  相似文献   
74.
Between 1979 and 1985, 166 patients with diffuse large cell (histiocytic) lymphoma were randomized to receive therapy with 3 courses of cyclophosphamide, doxorubicin (Adriamycin), vincristine, and prednisone (CAVP), with or without low-dose bleomycin, by continuous iv infusion. Responders were further randomized to 3 weeks of therapy with either high-dose methotrexate (3 g/m2 iv weekly with leukovorin rescue) or low-dose methotrexate (30 mg/m2 orally weekly without rescue). Therapy was concluded with 3 additional courses of CAVP. No significant differences among the 4 treatment programs were observed in complete response rates (ranging from 46% to 51%) or in failure-free survival. Of the 38 relapses that have occurred in patients treated with low-dose methotrexate, 5 included relapse in the central nervous system in conjunction with systemic relapse. However, none of 31 relapses observed in patients receiving high-dose methotrexate have occurred with involvement of the central nervous system. Patients entering this study with "B" symptoms had significantly poorer treatment results than those patients entering study without "B" symptoms.  相似文献   
75.
Advances in Health Sciences Education - Critical reflection supports enactment of the social roles of care, like collaboration and advocacy. We require evidence that links critical teaching...  相似文献   
76.
Ketogenic diets (KDs) often contain high levels of saturated fat, which may increase liver fat, but the lower carbohydrate intake may have the opposite effect. Using a controlled feeding design, we compared liver fat responses to a hypocaloric KD with a placebo (PL) versus an energy-matched low-fat diet (LFD) in overweight adults. We also examined the added effect of a ketone supplement (KS). Overweight adults were randomized to a 6-week KD (KD + PL) or a KD with KS (KD + KS); an LFD group was recruited separately. All diets were estimated to provide 75% of energy expenditure. Weight loss was similar between groups (p > 0.05). Liver fat assessed by magnetic resonance imaging decreased after 6 week (p = 0.004) with no group differences (p > 0.05). A subset with nonalcoholic fatty liver disease (NAFLD) (liver fat > 5%, n = 12) showed a greater reduction in liver fat, but no group differences. In KD participants with NAFLD, 92% of the variability in change in liver fat was explained by baseline liver fat (p < 0.001). A short-term hypocaloric KD high in saturated fat does not adversely impact liver health and is not impacted by exogenous ketones. Hypocaloric low-fat and KDs can both be used in the short-term to significantly reduce liver fat in individuals with NAFLD.  相似文献   
77.
Background. Foods rich in saturated fatty acids (SFAs) have been discouraged by virtue of their cholesterol-raising potential, but this effect is modulated by the food source and background level of carbohydrate. Objective. We aimed to compare the consumption of palm stearin (PS) versus butter on circulating cholesterol responses in the setting of both a low-carbohydrate/high-fat (LC/HF) and high-carbohydrate/low-fat (HC/LF) diet in healthy subjects. We also explored effects on plasma lipoprotein particle distribution and fatty acid composition. Methods. We performed a randomized, controlled-feeding, cross-over study that compared a PS- versus a Butter-based diet in a group of normocholesterolemic, non-obese adults. A controlled canola oil-based ‘Run-In’ diet preceded the experimental PS and Butter diets. All diets were eucaloric, provided for 3-weeks, and had the same macronutrient distribution but varied in primary fat source (40% of the total fat). The same Run-In and cross-over experiments were done in two separate groups who self-selected to either a LC/HF (n = 12) or a HC/LF (n = 12) diet track. The primary outcomes were low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein (HDL)-C, triglycerides, and LDL particle distribution. Results. Compared to PS, Butter resulted in higher LDL-C in both the LC/HF (13.4%, p = 0.003) and HC/LF (10.8%, p = 0.002) groups, which was primarily attributed to large LDL I and LDL IIa particles. There were no differences between PS and Butter in HDL-C, triglycerides, or small LDL particles. Oxidized LDL was lower after PS than Butter in LC/HF (p = 0.011), but not the HC/LF group. Conclusions. These results demonstrate that Butter raises LDL-C relative to PS in healthy normocholesterolemic adults regardless of background variations in carbohydrate and fat, an effect primarily attributed to larger cholesterol-rich LDL particles.  相似文献   
78.
Journal of Immigrant and Minority Health - Over 8100 people living with HIV (PLWH) in Oregon are at risk of acquiring COVID-19, and communities of color are disproportionately impacted by both...  相似文献   
79.

To examine the health status of Hispanic agricultural workers in Florida and Georgia. Health data from agricultural workers in the Farm Worker Family Health Program (June 2019) and research studies in Florida (May 2015 and May 2019) were examined. Data from 728 agricultural workers were collected through sociodemographic questionnaire and clinical data. In the Florida sample, 83% were overweight or obese, 70% elevated blood pressure, 60% met the definition of prediabetes. In Georgia, 64% were overweight or obese and 67% had elevated blood pressure. Weak correlations were observed between BMI and systolic blood pressure (unadjusted r?=?0.20), diastolic blood pressure (unadjusted r?=?0.19), and glucose (unadjusted r?=?0.14). Adjusting for age and gender did not show statistically significant correlation between BMI and systolic and diastolic blood pressure or glucose. While BMI has been shown to be strongly associated with high blood pressure and impaired glucose, we found a weak correlation among agricultural workers. Given the common and high use of pesticides and elevated rates of hypertension, impaired glucose, and adiposity in agricultural workers, the public health impact of this relationship may require and lead to occupational reform that protects the health of agricultural workers. Future studies should assess occupational and environmental factors and lifestyle differences between agricultural workers and the general population to better understand these discrepancies in health status.

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80.
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