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951.
952.
Summary The effect of feeding S. obliquus on two freshwater fishes Puntius ticto and Trichogaster fasciatus has been studied. It is observed that there is overall improvement in the conditions of the fishes and a marked increase in weight, volume and measurements has been observed as compared to control.  相似文献   
953.
Smoking among Malaysian adolescents remains a public health concern despite concerted efforts in tobacco control. The aims of this study were to examine the prevalence and determinants of current-smoking status in young adolescents. This cross sectional study used the first round of the Malaysian Health and Adolescents Research Team’s prospective cohort study. It was conducted in three States of the Central and Northern regions of Peninsular Malaysia between March and May 2012. The study used the multistage stratified sampling design. A total of 1,342 adolescents of both sexes, aged 12-13 years, were sampled from randomly selected urban and rural national schools. Information on current smoking status and associated factors were collected by a self-administered, pre-tested, validated, structured questionnaire. Seven percent of the samples were current-smokers; the majority (62%) of them started smoking at the age of 11 years or below. The prevalence of current smoking was significantly higher in males (odds ratio [OR] = 2.37; 95% CI: 1.46, 3.84), those who were influenced by smoker friends (OR = 8.35; 95% CI: 4.90, 14.25), who were unaware of the health risks of smoking (OR =1.85; 95% CI: 1.02, 3.36) and who reported a lack of satisfaction about their overall life (OR =3.26; 95% CI: 1.73, 6.12). The study findings provide valuable information to strengthen the existing school-based smoking prevention program through integration of social competence and social influence curricula. The program should empower the young adolescents to refuse tobacco offers, to overcome social influences and to resist peer pressure to avoid starting smoking. Particular focuses to include mental health service to prevent both emotional and behavioural problems are needed.  相似文献   
954.
Series of experiments were undertaken to investigate whether application of Precocene II (PII) to parasitized S. littoralis larvae can influence their THCs and DHCs. PII was applied in single dose treatments (70μg/5 μl/dose). Haemolymph samples were taken at daily intervals from day 3 to day 8 post‐treatments. Two distinct alterations were noted; first, PII‐treatments caused significant decrease in THCs. Once the parasitoid larvae emerge from either treated or untreated hosts, a sharp decline in THCs was observed. The second effect was changes in DHCs of S. littoralis larvae. In controls, haemocyte types could be arranged in descending order due to their relative occurrence into plasmatocytes (PLs), prohaemocytes (PRs), spherule cells (SPs), granular cells (GRs) and oenocytoids (OEs). This order changed in treated hosts to PLs, GRs, PRs, SPs and OEs, i.e., GRs that were less prevalent in the haemolymph of control larvae increased significantly in PII‐treated hosts. In the latters, sharp rise in GRs levels followed parasitoid emergence. OEs cells were scarce in both treated and untreated hosts. No significant difference was observed between the overall means of PLs in both types of host larvae. But GRs‐PRs was markedly altered in treated larvae.  相似文献   
955.
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Mycobacterium tuberculosis complex (MTBC) is notorious for causing diseases, such as tuberculosis. Tuberculosis caused by M. tuberculosis remains a global public health concern. Two prophages, phiRv1 and phiRv2, can be found among most MTBC genomes. However, no precise functions have been assigned for the two prophages. In this paper, to find out the function of these two prophages, the distribution and function of phiRv1 and phiRv2 in MTBC genomes were analyzed from multiple omics data. We found that complex insertion, deletion, and reorganization appeared on the locus of two prophages in MTBC genomes; some genes of the two prophages can be translated and are functional from proteomic data; the expression of other prophage genes, such as Rv1577c, Rv2650c, Rv2652c, Rv2659c, and Rv2658c, can vary with environmental stresses and might enhance the fitness of MTBC. These data will facilitate our in-depth understanding of their function.  相似文献   
958.
Biomechanics and Modeling in Mechanobiology - In this paper, the material length scale parameter of the modified couple stress theory for trabecular bones is studied. For this reason, experimental...  相似文献   
959.
An essential aspect of stem cell culture is the successful maintenance of the undifferentiated state. Many types of stem cells are FGF2 dependent, and pluripotent stem cells are maintained by replacing FGF2-containing media daily, while tissue-specific stem cells are typically fed every 3rd day. Frequent feeding, however, results in significant variation in growth factor levels due to FGF2 instability, which limits effective maintenance due to spontaneous differentiation. We report that stabilization of FGF2 levels using controlled release PLGA microspheres improves expression of stem cell markers, increases stem cell numbers and decreases spontaneous differentiation. The controlled release FGF2 additive reduces the frequency of media changes needed to maintain stem cell cultures, so that human embryonic stem cells and induced pluripotent stem cells can be maintained successfully with biweekly feedings.  相似文献   
960.

Iron deficiency is one of the most prevailing micronutrient deficiencies throughout the globe. Iron malnutrition affects billions of people around the world especially children and pregnant women. Its deficiencies can be overcome through microbial biofortification: a process of deliberately increasing desirable nutrients in crop plants. Plant growth-promoting rhizobacteria (PGPR) can improve iron content in edible plant tissues through different direct and indirect mechanisms. Adding plant growth regulators along with rhizobacteria makes it a novel fortification approach. In the current experiment, the interactive effect of two bacterial isolates (O-13 & K-10) alone and in consortium with l-tryptophan in the presence of iron sulfate was evaluated on growth, physiology, tuber characteristics, and iron concentration in potato (Solanum tuberosum L.). Results revealed that inoculation with PGPR and plant growth regulator (PGR) significantly improved the plant height, straw yield, and the number of tubers per plant. Potato (Solanum tuberosum L.) tuber characteristics (starch content, vitamin-C, relative water content) were also improved significantly. O-13, K-10, and l-tryptophan had significantly improved the iron concentration up to 20.59, 33.12, and 28.95%, respectively. However, inoculation with the microbial consortium and l-tryptophan showed a significant increase of up to one-fold in the iron concentration of potato (Solanum tuberosum L.) as compared with uninoculated control. The results suggest that rhizobacteria can help the plant to uptake nutrients from the soil. These findings concluded on the fact that the interactive effect of microbial assisted biofortification and plant growth regulator is a novel, promising, and cost-effective approach to mitigate micronutrient deficiencies especially in resource-limited countries.

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