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排序方式: 共有178条查询结果,搜索用时 31 毫秒
1.
Detection of urinary TNF, IL 1, and IL 2 after local BCG immunotherapy for bladder carcinoma 总被引:2,自引:0,他引:2
Intravesical application of bacillus Calmette-Guérin (BCG) is highly active against recurrences of superficial urothelial bladder carcinoma. In an attempt to monitor the immunological effects of this therapy, we analyzed the urine of patients following the sixth intravessical instillation, to show the presence of the monokines TNF and IL 1 and the lymphokine IL 2. Within 24 hours following the instillation, all (n = 10) patients exhibited a strong increase in urinary cytokine secretion, which was significantly different from the control group (n = 10), with respect to TNF L929 biological assay (P less than 0.01), TNF sandwich-ELISA (P less than 0.01), IL 2 CTL 6 biological assay (P less than 0.05), IL 2 sandwich-ELISA (P less than 0.005), and IL 1 sandwich-ELISA (P less than 0.05), but not to the IL 1 fibroblast biological assay. The maximum urinary secretion varied between individual patients and different cytokines, but was generally found within 2 to 8 hr after the instillation. A persistent high urinary activity was demonstrated in BCG-treated patients for IL 2 in sandwich-ELISA. These results reflect the local inflammatory response to BCG and suggest an immunomodulatory mode of action against urothelial carcinoma cells. Elucidation of the possible role of each urinary cytokine against this cancer warrants further investigations. 相似文献
2.
Crouch Connor D. Grady Amanda M. Wilhelmi Nicholas P. Hofstetter Richard W. DePinte Daniel E. Waring Kristen M. 《Biological invasions》2021,23(9):2893-2912
Biological Invasions - Oystershell scale (OSS; Lepidosaphes ulmi) is an emerging invasive insect that poses a serious threat to conservation of quaking aspen (Populus tremuloides) in the... 相似文献
3.
D Wang CR Stockard L Harkins P Lott C Salih K Yuan 《Biotechnic & histochemistry》2013,88(3-4):179-189
Angiogenesis, or neovascularization, is known to play an important role in the neoplastic progression leading to metastasis. CD31 or Factor VIII-related antigen (F VIII RAg) immunohistochemistry is widely used in experimental studies for quantifying tumor neovascularization in immunocompromised animal models implanted with transformed human cell lines. Quantification, however, can be affected by variations in the methodology used to measure vascularization including antibody selection, antigen retrieval (AR) pretreatment, and evaluation techniques. To examine this further, we investigated the microvessel density (MVD) and the intensity of microvascular staining among five different human tumor xenografts and a mouse syngeneic tumor using anti-CD31 and F VIII RAg immunohistochemical staining. Different AR methods also were evaluated. Maximal retrieval of CD31 was achieved using 0.5 M Tris (pH 10) buffer, while maximum retrieval of F VIII RAg was achieved using 0.05% pepsin treatment of tissue sections. For each optimized retrieval condition, anti-CD31 highlighted small vessels better than F VIII RAg. Furthermore, the MVD of CD31 was significantly greater than that of F VIII RAg decorated vessels (p<0.001). The choice of antibody and AR method has a significant affect on immunohistochemical findings when studying angiogenesis. One also must use caution when comparing studies in the literature that use different techniques and reagents. 相似文献
4.
Lengthened circadian period of locomotor activity is a characteristic of a congenic strain of mice carrying a nonsense mutation in exon 5 of the carbonic anhydrase II gene, car2. The null mutation in car2 is located on a DBA/2J inbred strain insert on proximal chromosome 3, on an otherwise C57BL/6J genomic background. Since reducing the size of the congenic region would narrow the possible candidate genes for period, two recombinant congenic strains (R1 and R2) were developed from the original congenic strain. These new congenic strains were assessed for period, genetic composition, and the presence of immunoreactive carbonic anhydrase II. R1 mice were homozygous DBA/2J for the distal portion of the original DBA/2J insert, while R2 mice were homozygous DBA/2J for the proximal portion. R1 mice had a significantly lengthened period compared to R2 mice and wild-type C57BL/6J mice, indicating that the gene(s) affecting period is likely found within the reduced DBA/2J insert (~1 cM) in the R1 mice. The R1 mice also possessed the null mutation in car2. This study confirmed the presence of a gene(s) affecting period on proximal chromosome 3 and significantly reduced the size of the congenic region and the number of candidate genes. Future studies will focus on identifying the gene influencing period. 相似文献
5.
Tenzer A Hofstetter B Sauser C Bodis S Schubiger AP Bonny C Pruschy M 《Proteomics》2004,4(9):2796-2804
Proteolytic activation of zymogens or controlled degradation of inhibitory factors is part of a major regulatory system on the post-translational level to regulate treatment induced cellular stress responses. The identification of differential activity based substrates is thus of high interest to prioritize and validate candidate targets for drug discovery. Here we present a novel subtractive substrate phage display screening method for the selection of treatment induced post-translational peptide modifications in complex proteomes. We investigated this approach with tumor cells in response to a protease activating anticancer treatment modality using subtractive and iterative screening of cellular extracts derived from control and treated cells. Specific phage were identified that served as substrates for proteolytic activities in response to treatment related activity changes and could be distinguished from substrates for unspecific proteolytic background activities. Novel, selected peptide substrates were investigated in vitro and in vivo and showed high substrate specificity and functional biological significance. 相似文献
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Stefanie?HellwegEmail author Thomas?B.?Hofstetter Konrad?Hungerbuhler 《The International Journal of Life Cycle Assessment》2003,8(1):8-18
Background In Life-Cycle Assessment (LCA), decision makers are often faced with tradeoffs between current and future impacts. One typical
example is waste incineration, where immediate emissions to the air from the incineration process have to be weighted against
future emissions of slag landfills. Long-term impacts are either completely taken into account or they are entirely disregarded
in case of a temporal cut-off. Temporal cutoffs are a special case of discounting.
Objective In this paper, discounting is defined as valuing damages differently at different points of time using a positive or negative
discount rate. Apart from temporal cut-offs, discounting has rarely been applied in LCA so far. It is the goal of this paper
to discuss the concept of discounting and its applicability in the context of LCA.
Methods For this purpose, we first review the arguments for discounting and its principles in economic sciences. Discounting in economics
can be motivated by pure time preference, productivity of capital, diminishing marginal utility of consumption, and uncertainties.
The nominal discount rate additionally includes changes in the price level. These arguments and their justification are discussed
in the context of environmental impacts harming future generations.
Results and Discussion It is concluded that discounting across generations because of pure time preference contradicts fundamental ethical values
and should therefore not be applied in LCA. However, it has to be acknowledged that in practice decision makers often use
positive discount rates because of pure time preference — either because they might profit from imposing environmental damage
on others instead of themselves or because people in the far future are not of immediate concern to them. Discounting because
of the productivity of capital assumes a relationship between monetary values and environmental impact. If such a relationship
is accepted, discounting could be applied. However, future generations should be compensated for the environmental damage.
It is likely that they would demand a higher compensation if the real per capita income increases. As both the compensation
and the discount rate are related to economic growth, the overall discount rate might be close to zero. It is shown that the
overall discount rate might even be negative considering that the required compensation could increase (even to infinite)
if natural assets remain scarce, whereas the utility of consumption diminishes with increasing income. Uncertainties could
justify both positive and negative discount rates. Since the relationship between uncertainties and the magnitude of damage
is generally not exponential, we recommend to model changes in the magnitude of damage in scenario analysis instead of considering
it in discounting (which requires an exponential function of time in the case of a constant discount rate). We investigated
the influence of discounting in a case study of heavy metal emissions from slag landfills. It could be shown that even small
discount rates of less than 1 % lead to a significant reduction of the impact score, whereas negative discount rates inflate
the results.
Conclusions and Recommendations Discounting is only applicable when temporally differentiated data is available. In some cases, such a temporal differentiation
is necessary to take sound decisions, especially when long emission periods are involved. An example is the disposal of nuclear
or heavy metal-containing waste. In these cases, the results might completely depend on the discount rate. This paper helps
to structure arguments and thus to support the decision about whether or not discounting should be applied in an LCA. 相似文献
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10.
Chris CR Smith Lisa K Snowberg J Gregory Caporaso Rob Knight Daniel I Bolnick 《The ISME journal》2015,9(11):2515-2526
To explain differences in gut microbial communities we must determine how processes regulating microbial community assembly (colonization, persistence) differ among hosts and affect microbiota composition. We surveyed the gut microbiota of threespine stickleback (Gasterosteus aculeatus) from 10 geographically clustered populations and sequenced environmental samples to track potential colonizing microbes and quantify the effects of host environment and genotype. Gut microbiota composition and diversity varied among populations. These among-population differences were associated with multiple covarying ecological variables: habitat type (lake, stream, estuary), lake geomorphology and food- (but not water-) associated microbiota. Fish genotype also covaried with gut microbiota composition; more genetically divergent populations exhibited more divergent gut microbiota. Our results suggest that population level differences in stickleback gut microbiota may depend more on internal sorting processes (host genotype) than on colonization processes (transient environmental effects). 相似文献