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Plasmodium vivax research has been hampered by the lack of technology for culturing this parasite. Culturing P. vivax is difficult because the parasite selectively invades reticulocytes. Here we describe a modified procedure to establish and maintain short-term cultures of freshly collected P. vivax parasites using reticulocyte-enriched cord blood. Using this method, parasites could be cultured for a month. Manipulation of the culture allowed procurement of synchronized stages of the parasite. This short-term culture method can be easily adapted to study various aspects of the parasite biology.  相似文献   
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本文根据营养动力学理论,建立了一类种间竞争的新的数学模型:它是单种群增长的Cui-Lawson模型,在种间竞争上的推广。新的种间竞争模型克服了经典的种间竞争的Lotka-Volteira方程的局限与不足,具有更广泛和复杂的行为,并在特殊条件下以Lotka-Volterra竞争方程为其特例。因此,新的种间竞争的数学模型是更一般的解释性模型,是对经典的Lotka-Voterra竞争方程的扩充。  相似文献   
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Despite the fact that long noncoding RNAs (lncRNAs) play roles in almost all biological processes, little is known about their biological function in the endometrium during the formation of endometrial receptivity. In this study, a comprehensive analysis of lncRNAs in goat endometrial tissues on Day 5 (prereceptive endometrium, PE) and Day 15 (receptive endometrium, RE) of pregnancy was performed by using RNA-Seq. As a result, 668 differentially expressed lncRNAs (DELs) were found between the PE and RE. Further study showed that lncRNA882, regulated by estrogen (E2) and progestin (P4), could act as competing endogenous RNAs (ceRNAs) for miR-15b, which inhibited the expression of transforming growth factor-b-activated kinase 1 binding protein 3 (TAB3) and then indirectly regulated the level of leukemia inhibitory factor (LIF). This was helpful for the formation of endometrial receptivity in dairy goats. In conclusion, we elucidated the endometrium lncRNA profiles of PE and RE in dairy goats; lncRNA882 acted as a ceRNA for miR-15b and then indirectly regulated the level of LIF in goat endometrial epithelium cells. Thus, this study helped us to better understand the molecular regulation of endometrial receptivity in dairy goats.  相似文献   
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Fast developments and substantial achievements have been shaping the field of wearable electronic devices, resulting in the persistent requirement for stretchable lithium‐ion batteries (LIBs). Despite recent progress in stretchable electrodes, stretching full batteries, including electrodes, separator, and sealing material, remains a great challenge. Here, a simple design concept for stretchable LIBs via a wavy structure at the full battery device scale is reported. All components including the package are capable of being reversibly stretched by folding the entire pouch cell into a wavy shape with polydimethylsiloxane filled in each valley region. In addition, the stretchable, sticky, and porous polyurethane/poly(vinylidene fluoride) membrane is adopted as a separator for the first time, which can maintain intimate contact between electrodes and separator to continuously secure ion pathway under dynamic state. Commercial cathode, anode, and package can be utilized in this rationally designed wavy battery to enable stretchability. The results indicate good electrochemical performances and long‐term stability at repeatable release–stretch cycles. A high areal capacity of 3.6 mA h cm?2 and energy density of up to 172 W h L?1 can be achieved for the wavy battery. The promising results of the cost‐effective wavy battery with high stretchability shed light on the development of stretchable energy storages.  相似文献   
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Background

Multiple primary cancers (MPC) have been identified as two or more cancers without any subordinate relationship that occur either simultaneously or metachronously in the same or different organs of an individual. Lynch syndrome is an autosomal dominant genetic disorder that increases the risk of many types of cancers. Lynch syndrome patients who suffer more than two cancers can also be considered as MPC; patients of this kind provide unique resources to learn how genetic mutation causes MPC in different tissues.

Methods

We performed a whole genome sequencing on blood cells and two tumor samples of a Lynch syndrome patient who was diagnosed with five primary cancers. The mutational landscape of the tumors, including somatic point mutations and copy number alternations, was characterized. We also compared Lynch syndrome with sporadic cancers and proposed a model to illustrate the mutational process by which Lynch syndrome progresses to MPC.

Results

We revealed a novel pathologic mutation on the MSH2 gene (G504 splicing) that associates with Lynch syndrome. Systematical comparison of the mutation landscape revealed that multiple cancers in the proband were evolutionarily independent. Integrative analysis showed that truncating mutations of DNA mismatch repair (MMR) genes were significantly enriched in the patient. A mutation progress model that included germline mutations of MMR genes, double hits of MMR system, mutations in tissue-specific driver genes, and rapid accumulation of additional passenger mutations was proposed to illustrate how MPC occurs in Lynch syndrome patients.

Conclusion

Our findings demonstrate that both germline and somatic alterations are driving forces of carcinogenesis, which may resolve the carcinogenic theory of Lynch syndrome.
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Recent studies have suggested that growth factors and hormones play important roles in cell prolif-eration and differentiation during early embryonic development. In the present study, we examined the expression and localization of insulin in the mouse oocytes and one-cell stage embryos by quantitative ELISA, RT-PCR, Western blot and immunofluorescence. In the mouse oocytes and one-cell stage em-bryos, expression of insulin was uniformly distributed in the cytoplasm. We also examined the expres-sion, activity and localization of mTOR (mammalian target of rapamycin) and p70S6K. The expression of mTOR and p70S6K was not significantly different at the cell cycle of mouse one-cell stage embryos. mTOR and S6K were distributed evenly in the cytoplasm at G1, G2 and M phase phase, but at S phase, the distribution of mTOR and S6K was around the pronucleus. At different phases, the activity of mTOR fluctuated. We also used the PI3K specific inhibitor-Wortmannin to investigate the cleavage rate of eggs. The result showed that the rate obviously decreased. When the mTOR specific inhibitor Rapa-mycin was used, the first mitotic division of the mouse one-cell stage embryo was delayed. These re-sults suggested that insulin was expressed both in mouse oocytes and one-cell stage embryos, and may play functional roles in regulation of mouse early embryogenesis by activating the signal pathway of PI3K/PKB/mTOR/S6K.  相似文献   
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