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71.
目的:研究铼.188标记生物分子在肿瘤治疗中的应用。方法:选取小白鼠作为实验的研究对象,将荷瘤鼠的肉瘤切成小块接种到小白鼠身上,达到试验条件时使用,即将没有明显差异的小白鼠16只随机分为4组,每组4只,注射含有铼一188的药物后分别在不同的时间将其处死,之后取出重要器官进行测量分析,进而得出铼一188的应用效果。结果:瘤内注射的要去在不同时间放射性在瘤内的保持率分别为(90.5±7.7)D%(1h),(92.2±8.6)D%(24h),(88.3±10.9)D%(48h)和(91.5±7.6)D%(72h),在荷瘤鼠内注入生理盐水、非放硫化铼和188Re.硫化铼混悬液,肿瘤质量分别为2885.3±1241.3、2839.9±1965.2和98.4±45.5mg。188Re-硫化铼混悬液在生理盐水、磷酸盐缓冲液和小牛血清中均可稳定72h,而且188W-188Re发生器的应用还可以降低188Re-硫化铼混悬液的价格。随着处死时间的延迟,小鼠肿瘤质量和体积逐渐减小,相临两组比较,后组测定值均明显小于前组,数据经统计学比较具有显著差异(P〈0.05)。结论:188Re-硫化铼混悬液是一种适宜的肿瘤治疗剂。  相似文献   
72.
Pentastiridius leporinus is an important vector of sugar beet pathogens in eastern France. An electron microscope survey on the insect-associated microflora revealed the occurrence of intranuclear prokaryotic cells in every internal organ analysed. These bacteria, which could also be found in the cytoplasm surrounding the nucleus, had a homogeneous coccoid (ca. 0.45 microm) or rod (0.45-1 microm) shape. The presence of three membrane layers was observed, the outermost forming a kind of vacuole containing generally a single microorganism. No cytopathological abnormalities were detected in the infected cells. To our knowledge, this is the first report of a hemipteran species infected by intranuclear bacteria. The possible identity of this microorganism is discussed.  相似文献   
73.

Background  

In August 2006 a major epidemic of bluetongue virus serotype 8 (BTV8) started off in North-West Europe. In the course of 2007 it became evident that BTV8 had survived the winter in North-West Europe, re-emerged and spread exponentially. Recently, the European Union decided to start vaccination against BTV8. In order to improve the understanding of the epidemiological situation, it was necessary to execute a cross-sectional serological study at the end of the BT vector season. Cattle were the target species for cross-sectional serological studies in Europe at the end of 2006 and 2007. However, there was no information on the BTV8-seroprevalence in sheep and goats.  相似文献   
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75.
It has been suggested that in a socially monogamous system where fathers invest in their mate's offspring but paternity is far from certain, it will be adaptive on the part of infants to conceal their father's identity; but the opposite claim has also been made that this is against the genetic interests of the fathers, and a high frequency of adulterine births will select instead for paternal resemblance. In this article, I present a simple theoretical model that suggests that neonatal anonymity benefits fathers, mothers, and children. Once anonymity becomes established, however, all babies start paying the cost of paternity uncertainty, that is, the reduction in paternal care due to fathers not knowing whether they have truly sired their mate's offspring. By diminishing the fitness of babies, such a cost bounces back as lowered fitness for parents as well. We should then expect the evolution of maternal strategies directed to decrease paternity uncertainty, in the form of instinctive and unsolicited comments on babies' resemblance to their putative fathers. In contradiction to the widespread belief that it would be in fathers' interest to be skeptical of these allegations, the model suggests that, under conditions of infant anonymity, fathers will actually promote their own fitness by believing their spouses. Received in revised form: 5 September 2001 Electronic Publication  相似文献   
76.
G Bressan  R Rampone  E Bianchi  A Ciferri 《Biopolymers》1974,13(11):2227-2240
Optical density, viscosity, and light scattering measurements for calf thymus DNA in water–N,N dimethyl formamide (DMF) solutions are presented. DMF content varied between 0 and 60% (v/v) and DNA molecular weight varied between 15 × 106 and 0.5 × 106. Complementary measurements of the solubility of adenine, thymine, guanine, and cytosine in H2O–DMF mixtures are presented. The denaturation temperature of DNA, manifested by about a 35% increase of optical density, is gradually depressed by increasing DMF content. However, a significant increase of OD occurs even before (and even after) the denaturation point, when DMF content is increased isothermally. The intrinsic viscosity also exhibits a large decrease when DMF content is increased both before and after the denaturation point. Light scattering data for high-molecular-weight DNA in the predenaturation range indicate a decrease of the mean-square radius and a constant molecular weight on increasing DMF content. The results, interpreted in terms of the wormlike chain of Kratky and Porod, indicate a large decrease of the persistence length of DNA. For low-molecular-weight DNA, radius and molecular weight increase with DMF content, indicating intermolecular aggregation. The formation of compact structures of native DNA is discussed in terms of an increased solubility of uncharged bases, and a decreased solubility of phosphate and deoxyribose groups, when a less polar environment is provided by the addition of DMF.  相似文献   
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78.
The main aim of this investigation was to study the regulatory roles of let-7b and miR-155-3p on the expression of inflammation-associated genes in monocytes, macrophages, and lipopolysaccharide (LPS)-activated macrophages (AcM). A second goal was to analyze the potential modulatory roles of different fatty acids, including oleic, palmitic, eicosapentaenoic (EPA), and docosahexaenoic (DHA), on the expression of these miRNAs in the three cell types. This hypothesis was tested in human acute monocytic leukemia cells (THP-1), which were differentiated into macrophages with 2-O-tetradecanoylphorbol-13-acetate (TPA) and further activated with LPS for 24 h. Monocytes, macrophages, and AcM were transfected with a negative control, or mimics for miR-155-3p and miR-let-7b-5p. The expression of both miRNAs and some proinflammatory genes was analyzed by qRT-PCR. Interestingly, let-7b mimic reduced the expression of IL6 and TNF in monocytes, and SERPINE1 expression in LPS-activated macrophages. However, IL6, TNF, and SERPINE1 were upregulated in macrophages by let-7b mimic. IL6 expression was higher in the three types of cells after transfecting with miR-155-3p mimic. Similarly, expression of SERPINE1 was increased by miR-155-3p mimic in monocytes and macrophages. However, TLR4 was downregulated by miR-155-3p in monocytes and macrophages. Regarding the effects of the different fatty acids, oleic acid increased the expression of let-7b in macrophages and AcM and also increased the expression of miR-155 in monocytes when compared with DHA but not when compared with non-treated cells. Overall, these results suggest anti- and proinflammatory roles of let-7b and miR-155-3p in THP-1 cells, respectively, although these outcomes are strongly dependent on the cell type. Noteworthy, oleic acid might exert beneficial anti-inflammatory effects in immune cells (i.e., non-activated and LPS-activated macrophages) by upregulating the expression of let-7b.  相似文献   
79.
We analyzed whether global and inflammatory genes methylation can be early predictors of metabolic changes and their associations with the diet, in a cross-sectional study (n?=?40). Higher global methylation was associated to adiposity, insulin resistance, and lower quality of the diet. Methylation of IL-6, SERPINE1 and CRP genes was related to adiposity traits and macronutrients intake. SERPINE1 hypermethylation was also related to some metabolic alterations. CRP methylation was a better predictor of insulin resistance than CRP plasma concentrations. Global and inflammatory gene promoter hypermethylation can be good early biomarkers of adiposity and metabolic changes and are associated to the quality of the diet.  相似文献   
80.
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