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101.

Background

Male circumcision (MC) has been shown to reduce the risk of male genital diseases. MC is not commonly practiced among Chinese males and little is known about the factors associated with their knowledge of and willingness for MC. This study was to explore the knowledge regarding the foreskin among Chinese males and to identify factors associated with their willingness to undergo circumcision.

Methods

A total of 237 patients with redundant prepuce/phimosis were interviewed through face-to-face interviews. The items on the questionnaire included: demographics, an objective scale assessing knowledge about the foreskin, willingness to have MC, the attitudes of sexual partners and doctors toward redundant prepuce/phimosis, and the approaches that patients used to acquire knowledge regarding the prepuce. Univariate analysis and multiple logistic regression analysis were performed to identify factors that are associated with willingness to be circumcised (WTC).

Results

A total of 212 patients completed the interview. Multivariable logistic regression showed that three factors were significantly associated with WTC: being married (OR = 0.43), perceiving redundant prepuce/phimosis as a disease (OR = 1.93), and if a patient’s partner supported MC (OR = 1.39). 58% (n = 122) had received information about the foreskin from another party: 18% (n = 37) from school, 8% (n = 17) from family, 17% (n = 36) from friends, 27% (n = 57) from health care providers. About 4% (n = 8) believed that their partners disliked their redundant prepuce/phimosis. 20% (n = 42) had received doctors’ advice to undergo circumcision.

Conclusion

Knowledge about the foreskin was low among Chinese males. Our study elucidates the factors associated with WTC and suggests that more education of the population about the foreskin can help improve the recognition of a correctible abnormality and help patients assess the potential role of MC in their health.  相似文献   
102.
【目的】研究和厚朴酚(HNK)抑制MRSA生物被膜(BF)形成的作用机制。【方法】使用TTC法测定了HNK对供试菌株BF的形成和成熟BF的抑制作用;刚果红平板法定性检测了HNK对PIA合成的影响;分光光度法测定了HNK对供试菌株eDNA释放量的影响;RT-PCR技术检测了HNK对供试菌株icaA、cidA以及agrA基因表达量的影响。【结果】HNK对MRSA 41573 BF的形成和成熟BF均有较强的抑制作用,其中,HNK抑制MRSA 41573 BF形成的MIC和MBC分别为10μg/mL和20μg/mL;抑制成熟BF的MIC和MBC分别为50μg/mL和100μg/mL。当用亚抑菌浓度的HNK与万古霉素联合作用后,可显著提高成熟BF对万古霉素的敏感性。HNK能显著抑制PIA的合成,且呈浓度剂量依赖。HNK能抑制供试菌株eDNA的释放量,其中1/8 MIC的HNK作用供试菌株16 h后,与对照组相比,e DNA的释放量降低了28.3%。HNK可抑制供试菌株BF形成的相关基因,其中1/2 MIC的HNK作用供试菌株16 h后,与对照相比,icaA的表达量降低了59.1%,cidA的表达量降低了56%,agrA的表达量降低了72.3%。【结论】HNK能显著抑制MRSA 41573 BF的形成,其作用机制主要是通过抑制icaA和cidA基因表达量,影响PIA和eDNA的合成,进而抑制BF的形成。此外HNK也可通过调控细菌的QS系统影响BF的形成。  相似文献   
103.
In this work, a simple electrochemical immunosensor was developed for the detection of carcinoembryonic antigen (CEA) based on rhombic dodecahedral Cu2O nanocrystals–graphene oxide–gold nanoparticles (rCu2O–GO–AuNPs). GO as the template and surfactant resulting in rCu2O exhibit improved rhombic dodecahedral structure uniformity and excellent electrochemical performance. Moreover, GO was found to be able to effectively improve the long stability of rCu2O on the electrode response. Under optimal conditions, the immunosensor showed a low limit of detection (0.004 ng ml−1) and a large linear range (0.01–120 ng ml−1). This work presents a potential alternative for the diagnostic applications of GO-supported special morphology materials in biomedicine and biosensors.  相似文献   
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105.
ADP‐ribosylation factors (ARFs) are small GTP‐binding proteins that regulate a wide variety of cell functions. Previously, we isolated a new ARF, ZmArf2, from maize (Zea mays). Sequence and expression characteristics indicated that ZmArf2 might play a critical role in the early stages of endosperm development. In this study, we investigated ZmArf2 function by analysis of its GTP‐binding activity and subcellular localization. We also over‐expressed ZmArf2 in Arabidopsis and measured organ and cell size and counted cell numbers. The expression levels of five organ size‐associated genes were also determined in 35S::ZmArf2 transgenic and wild‐type plants. Results showed that the recombinant ZmArf2 protein purified from Escherichia coli exhibited GTP‐binding activity. Subcellular localization revealed that ZmArf2 was localized in the cytoplasm and plasma membrane. ZmArf2 over‐expression in Arabidopsis showed that 35S::ZmArf2 transgenic plants were taller and had larger leaves and seeds compared to wild‐type plants, which resulted from cell expansions, not an increase in cell numbers. In addition, three cell expansion‐related genes, AtEXP3, AtEXP5 and AtEXP10, were upregulated in 35S::ZmArf2 transgenic lines, while the expression levels of AtGIF1 and AtGRF5, were unchanged. Collectively, our studies suggest that ZmArf2 has an active GTP‐binding function, and plays a crucial role in growth and development in Arabidopsis through cell expansion mediated by cell expansion genes.  相似文献   
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107.
Length‐weight relationships (LWRs) were determined for five endemic fish species from the Yalong and Wujiang rivers (tributaries of the Yangtze River, China): Folifer brevifilis (Peters, 1881), Pelteobagrus ussuriensis (Dybowski, 1872), Schistura fasciolata (Nichols & Pope, 1927), Triplophysa daqiaoensis (Ding, 1993) and Triplophysa orientalis (Herzenstein, 1888). Samples were obtained between April 2004 and July 2014 using various fishing gear (set nets, drift gill nets, fish cages, hook and electro fishing). For each specimen from each species the sample size was recorded, total length and weight were measured and the LWR determined. Further, the 95% confidence intervals of a and b, and coefficient of correlation were estimated. Prior to this study, the LWRs for these five species were unknown.  相似文献   
108.
Brassica napus (rapeseed) is a recent allotetraploid plant and the second most important oilseed crop worldwide. The origin of B. napus and the genetic relationships with its diploid ancestor species remain largely unresolved. Here, chloroplast DNA (cpDNA) from 488 B. napus accessions of global origin, 139 B. rapa accessions and 49 B. oleracea accessions were populationally resequenced using Illumina Solexa sequencing technologies. The intraspecific cpDNA variants and their allelic frequencies were called genomewide and further validated via EcoTILLING analyses of the rpo region. The cpDNA of the current global B. napus population comprises more than 400 variants (SNPs and short InDels) and maintains one predominant haplotype (Bncp1). Whole‐genome resequencing of the cpDNA of Bncp1 haplotype eliminated its direct inheritance from any accession of the B. rapa or B. oleracea species. The distribution of the polymorphism information content (PIC) values for each variant demonstrated that B. napus has much lower cpDNA diversity than B. rapa; however, a vast majority of the wild and cultivated B. oleracea specimens appeared to share one same distinct cpDNA haplotype, in contrast to its wild C‐genome relatives. This finding suggests that the cpDNA of the three Brassica species is well differentiated. The predominant B. napus cpDNA haplotype may have originated from uninvestigated relatives or from interactions between cpDNA mutations and natural/artificial selection during speciation and evolution. These exhaustive data on variation in cpDNA would provide fundamental data for research on cpDNA and chloroplasts.  相似文献   
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110.
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