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41.
Lou TF  Gray CW  Gray DM 《Oligonucleotides》2003,13(5):313-324
Two sets of 20-mer phosphorothioate-modified oligodeoxynucleotide DNAs (sODN) and 21-mer or 22-mer small interfering RNAs (siRNAs), targeted to the same coding sites in raf-1 mRNA, were compared for their abilities to reduce the amount of endogenously expressed Raf-1 protein in T24 cells. The amount of Raf-1 protein was monitored by careful quantitation of Western blots. We found that the siRNAs were somewhat less effective than the S-ODNs in reducing the Raf-1 protein level 20 hours after a 4-hour transfection. The siRNA duplexes were characterized by circular dichroism (CD) spectra, and melting temperatures (Tm) were obtained for the siRNA duplexes and DNA x RNA hybrids formed by the S-ODNs. The S-ODNs differed in their effectiveness, the S-ODN that formed the more stable hybrid being the more effective in reducing the Raf-1 protein level, but the two siRNAs were equally effective despite a difference in Tm of about 20 degrees C. Finally, the siRNAs and S-ODNs had a comparable nonspecific effect on a nontargeted (Bcl-2) protein. Our data add to others in the literature that show it can be difficult to select siRNAs that are more effective than antisense ODNs in downregulating endogenously expressed proteins.  相似文献   
42.

Background

Poor nutrition is harmful to one’s health as it can lead to overweight and obesity and a number of chronic diseases. Understanding consumer perceptions toward diet and nutrition is critical to advancing nutrition-related population health interventions to address such issues. The purpose of this paper was to examine Canadians’ perceived health and diet status, compared to their actual health status, and general concern about their own diet and beliefs about health. Also analyzed were some of the perceived barriers to eating “healthy” foods, with a focus on the availability of “healthy” processed foods.

Methods

Two surveys were administered online to a group of Canadian panelists from all ten provinces during May 2010 to January 2011. Thirty thousand were invited; 6,665 completed the baseline survey and 5,494 completed the second survey. Panelists were selected to be nationally representative of the Canadian adult population by age, sex, province and education level, according to 2006 census data.

Results

Approximately one third of Canadians perceived their health or diet to be very good while very few Canadians perceived their health or diet to be very poor. While the majority of Canadians believed food and nutrition to be very important for improving one’s health, fewer Canadians were concerned about their own diets. The majority of Canadians reported difficulty finding “healthy” processed foods (low in salt and sugar and with sufficient vitamins and minerals). Many also reported difficulty finding healthy foods that are affordable.

Conclusion

Although consumers believe that nutrition is one of the most important factors for maintaining health, there are still a number of attitudinal and perceived environmental barriers to healthy eating.  相似文献   
43.
Y Tang  F Lou  J Wang  Y Li  S Zhuang 《Phytochemistry》2001,58(8):1251-1256
Two coumaroyl flavonol glycosides, isorhamnetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], and kaempferol 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside]-7-O-beta-D-glucopyranoside, were isolated from the n-BuOH extract of Ginkgo biloba leaves. These two, together with six other flavonol glycosides, kaempferol 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], quercetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], quercetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside]-7-O-beta-D-glucopyranoside, quercetin 3-O-beta-D-glucopyranosyl-(1-2)-alpha-L-rhamnopyranoside, quercetin 3-O-beta-rutinoside, and quercetin 3-O-beta-D-glucopyranoside, showed profound antioxidant activities in DPPH and cytochrome-c reduction assays using the HL-60 cell culture system.  相似文献   
44.
The age-related decline in immunity reduces the effectiveness of vaccines in older adults. Immunosenescence is associated with chronic, low-grade inflammation, and the accumulation of senescent cells. The latter express Bcl-2 family members (providing resistance to cell death) and exhibit a pro-inflammatory, senescence-associated secretory phenotype (SASP). Preexisting senescent cells cause many aging-related disorders and therapeutic means of eliminating these cells have recently gained attention. The potential consequences of senescent cell removal on vaccine efficacy in older individuals are still ignored. We used the Bcl-2 family inhibitor ABT-263 to investigate the effects of pre-vaccination senolysis on immune responses in old mice. Two different ovalbumin (OVA)-containing vaccines (containing a saponin-based or a CpG oligodeoxynucleotide adjuvant) were tested. ABT-263 depleted senescent cells (apoptosis) and ablated the basal and lipopolysaccharide-induced production of SASP-related factors in old mice. Depletion of senescent cells prior to vaccination (prime/boost) had little effect on OVA-specific antibody and T-cell responses (slightly reduced and augmented, respectively). We then used a preclinical melanoma model to test the antitumor potential of senolysis before vaccination (prime with the vaccine and OVA boost by tumor cells). Surprisingly, ABT-263 treatment abrogated the vaccine's ability to protect against B16 melanoma growth in old animals, an effect associated with reduced antigen-specific T-cell responses. Some, but not all, of the effects were age-specific, which suggests that preexisting senescent cells were partly involved. Hence, depletion of senescent cells modifies immune responses to vaccines in some settings and caution should be taken when incorporating senolytics into vaccine-based cancer therapies.  相似文献   
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47.
为了解荒漠地表甲虫的多样性特点及其与环境的关系,明确其环境指示作用,评估沙漠工程对荒漠地表甲虫多样性的影响,作者于2010年5-7月采用陷阱法调查了占尔班通古特沙漠南缘从沙漠腹地到沙漠绿洲交错区不同生境的地表甲虫物种多样性,其中包括沙漠腹地公路防护体系的干扰生境.结果如下:(1)共捕获地表甲虫54,527头,隶属于14...  相似文献   
48.
A novel HPLC-UV method with pre-column derivatization by using 2-mercaptoethanol was established for determination of 1,2-[bis(1,2-benzisoselenazolone-3(2H)-ketone)]-ethane (BBSKE) in dog plasma. The derivatives were identified by mass spectrometry. The method had a good linear range of 0.05-2 microg/ml (r(2)=0.9995). The lower limit of quantification (LOQ) was 0.05 microg/ml. The precision and accuracy were less than 7%. After dosing of BBSKE (30 mg/kg, p.o. and 0.79 mg/kg, i.v.) in dogs, AUC(0-t) were 5.72+/-2.42 and 1.35+/-0.41 microg h/ml; t(1/2) were 4.6+/-2.1 and 1.7+/-0.6h, respectively. The method was successfully applied to the pharmacokinetic study in dogs.  相似文献   
49.
Jiang J  Li J  Xu Y  Han Y  Bai Y  Zhou G  Lou Y  Xu Z  Chong K 《Plant, cell & environment》2007,30(6):690-699
Jasmonic acid (JA) is a well-known defence hormone, but its biological function and mechanism in rice root development are less understood. Here, we describe a JA-induced putative receptor-like protein (OsRLK, AAL87185) functioning in root development in rice. RNA in situ hybridization revealed that the gene was expressed largely in roots, and a fusion protein showed its localization on the plasma membrane. The primary roots in RNAi transgenic rice plants meandered and curled more easily than wild-type (WT) roots under JA treatment. Thus, this gene was renamed Oryza sativa root meander curling (OsRMC). The transgenic primary roots were shorter, the number of adventitious roots increased and the number of lateral roots decreased as compared to the WT. As well, the second sheath was reduced in length. Growth of both primary roots and second sheaths was sensitive to JA treatment. No significant change of JA level appeared in the roots between the transgenic rice line and WT. Expression of RSOsPR10, involved in the JA signalling pathway, was induced in transgenic rice. Western blotting revealed OsRMC induced by JA. Our results suggest that OsRMC of the DUF26 subfamily involved in JA signal transduction mediates root development and negatively regulates root curling in rice.  相似文献   
50.
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