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111.
This review aims to describe changes in breastfeeding and summarise the breastfeeding rates, duration and reasons of discontinuing 'any breastfeeding' or 'exclusive breastfeeding' in P.R. China. Breastfeeding rates in China fell during the 1970s when the use of breast milk substitutes became widespread, and reached the lowest point in the 1980s. As a result many efforts were introduced to promote breastfeeding. The breastfeeding rate in China started to increase in the 1990s, and since the mid-1990s 'any breastfeeding' rates in the majority of cities and provinces, including minority areas, have been above 80% at four months. But most cities and provinces did not reach the national target of 'exclusive breastfeeding' of 80%. The 'exclusive breastfeeding' rates in minority areas were relatively lower than comparable inland provinces. The mean duration of 'any breastfeeding' in the majority of cities or provinces was between seven and nine months. The common reasons for ceasing breastfeeding, or introducing water or other infant food before four months, were perceived breast milk insufficiency, mother going to work, maternal and child illness and breast problems. Incorrect traditional perceptions have a strong adverse influence on 'exclusive breastfeeding' in less developed areas or rural areas. China is a huge country, geographically and in population size, and there is considerable ethnic diversity. Therefore breastfeeding rates in different parts of China can vary considerably.  相似文献   
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Molecular and Cellular Biochemistry - Prostate cancer (PC) is the most common reproductive cancer in men and the third leading cause of cancer death among men worldwide. Recently targeted therapy...  相似文献   
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Single‐layered organic solar cells (OSCs) using nonfullerene acceptors have reached 16% efficiency. Such a breakthrough has inspired new sparks for the development of the next generation of OSC materials. In addition to the optimization of electronic structure, it is important to investigate the essential solid‐state structure that guides the high efficiency of bulk heterojunction blends, which provides insight in understanding how to pair an efficient donor–acceptor mixture and refine film morphology. In this study, a thorough analysis is executed to reveal morphology details, and the results demonstrate that Y6 can form a unique 2D packing with a polymer‐like conjugated backbone oriented normal to the substrate, controlled by the processing solvent and thermal annealing conditions. Such morphology provides improved carrier transport and ultrafast hole and electron transfer, leading to improved device performance, and the best optimized device shows a power conversion efficiency of 16.88% (16.4% certified). This work reveals the importance of film morphology and the mechanism by which it affects device performance. A full set of analytical methods and processing conditions are executed to achieve high efficiency solar cells from materials design to device optimization, which will be useful in future OSC technology development.  相似文献   
115.
Conditionally replicative adenoviruses (CRAds) were promising approach for solid tumour treatment, but its oncolytic efficiency and toxicity are still not satisfactory for further clinical application. Here, we developed the CAIX promotor (CAIXpromotor)‐controlled CRAd armed with a tumour suppressor absent in melanoma 2 (AIM2) to enhance its oncolytic potency. The CAIXpromotor‐AIM2 adenoviruses (Ad‐CAIXpromotor‐AIM2) could efficiently express E1A and AIM2 in renal cancer cells. Compared with Ad‐CAIXpromotor, Ad‐CAIXpromotor‐AIM2 significantly inhibited cell proliferation and enhanced cell apoptosis and cell killing, thus resulting in the oncolytic efficiency in 786‐O cells or OSRC‐2 cells. To explore the therapeutic effect, various Ads were intratumourally injected into OSRC‐2‐xenograft mice. The tumour growth was remarkably inhibited in Ad‐CAIXpromotor‐AIM2‐treated group as demonstrated by reduced tumour volume and weight with a low toxicity. The inflammasome inhibitor YVAD‐CMK resulted in the reduction of anti‐tumour activity by Ad‐CAIXpromotor‐AIM2 in vitro or in vivo, suggesting that inflammasome activation response was required for the enhanced therapeutic efficiency. Furthermore, lung metastasis of renal cancer mice was also suppressed by Ad‐CAIXpromotor‐AIM2 treatment accompanied by the decreased tumour fossil in lung tissues. These results indicated that the tumour‐specific Ad‐CAIXpromotor‐AIM2 could be applied for human renal cancer therapy. The therapeutic strategy of AIM2‐based CRAds could be a potential and promising approach for the therapy of primary solid or metastasis tumours.  相似文献   
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Clinical observations have revealed a strong association between estrogen receptor alpha (ERα)-positive tumors and the development of bone metastases, however, the mechanism underlying this association remains unknown. We cultured MCF-7 (ERα-positive) on different rigidity substrates. Compared with cells grown on more rigid substrates (100 kPa), cells grown on soft substrates (10 kPa) exhibited reduced spreading ability, a lower ratio of cells in the S and G2/M cell cycle phases, and a decreased proliferation rate. Using stable isotope labeling by amino acids (SILAC), we further compared the whole proteome of MCF-7 cells grown on substrates of different rigidity (10 and 100 kPa), and found that the expression of eight members of chaperonin CCT increased by at least 2-fold in the harder substrate. CCT folding activity was increased in the hard substrate compared with the soft substrates. Amplified in breast cancer 1 (AIB1), was identified in CCT immunoprecipitates. CCT folding ability of AIB1 increased on 100-kPa substrate compared with 10- and 30-kPa substrates. Moreover, using mammalian two-hybrid protein-protein interaction assays, we found that the polyglutamine repeat sequence of the AIB1 protein was essential for interaction between CCTζ and AIB1. CCTζ-mediated AIB1 folding affects the cell area spreading, growth rate, and cell cycle. The expressions of the c-myc, cyclin D1, and PgR genes were higher on hard substrates than on soft substrate in both MCF-7 and T47D cells. ERα and AIB1 could up-regulate the mRNA and protein expression levels of the c-myc, cyclin D1, and PgR genes, and that 17 β-estradiol could enhance this effects. Conversely, 4-hydroxytamoxifen, could inhibit these effects. Taken together, our studies demonstrate that some ERα-positive breast cancer cells preferentially grow on more rigid substrates. CCT-mediated AIB1 folding appears to be involved in the rigidity response of breast cancer cells, which provides novel insight into the mechanisms of bone metastasis.  相似文献   
118.
? Premise of the study: Microsatellite primers were developed for a heterostylous herb, Hedyotis chrysotricha to investigate the effect of habitat fragmentation on its genetic diversity and population structure. ? Methods and Results: Twelve primer sets were developed and their polymorphisms were tested on 47 individuals from two island populations of H. chrysotricha in Thousand Island Lake of China. The number of alleles per locus ranged from five to 10, with an average of seven alleles. Expected heterozygosity per locus ranged from 0.284 to 0.821 and observed heterozygosity ranged from 0.191 to 0.851. ? Conclusions: We showed that all of the 12 microsatellite markers developed for H. chrysotricha are polymorphic within populations, which should provide a powerful tool for assessing population structure and genetic diversity across fragmented and continuous populations, and for studying the genetic effects of habitat fragmentation on this species.  相似文献   
119.
Thraustochytrium is a unicellular marine protist for the commercial production of very long-chain polyunsaturated fatty acids (VLCPUFAs). Biosynthesis of these VLCPUFAs in the protist is catalysed by a PUFA synthase comprising three subunits, each with multiple catalytic domains. Among these domains, two tandem FabA-like dehydratase domains (DH1 and DH2) in subunit-C together are responsible for introducing double bonds in VLCPUFAs. Domain swapping analysis in yeast showed that the defective phenotype of a Scfas1 mutant could be complemented by expressing an engineered ScFAS1 gene in which the DH domain was replaced by a single DH1 or mutated DH2 of the two. Heterologous expression of the PUFA synthase in E. coli showed that the mutation of DH1 of the two or deletion of DH1 or substitution of DH1 with DH2 resulted in the complete loss of activity in the biosynthesis of VLCPUFAs. Mutation of DH2 of the two or deletion of the DH2 domain produced a small amount of DPA, but not docosahexaenoic acid (DHA). These results indicate that each of the two FabA-like domains of the PUFA synthase possesses distinct function. DH1 domain is essential for the biosynthesis of VLCPUFAs, but DH2 domain is required for the biosynthesis of DHA.  相似文献   
120.
用于分化为多种类型细胞的多能干细胞(PSC)体外培养技术已被广泛应用于生物学领域中.由PSC分化而来的肾脏类器官可基本还原生物体内肾脏的组织结构和部分功能,在肾脏疾病模型研究和药物筛选中有重要作用,继续改善肾脏类器官的结构、功能和成熟度将会对肾脏再生治疗提供极大的帮助.研究肾脏类器官的重点在于体外准确模拟体内肾脏的发育...  相似文献   
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