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排序方式: 共有325条查询结果,搜索用时 9 毫秒
61.
Mouyu Yang Dun Y. Sun Dietmar Zinner Christian Roos 《American journal of primatology》2009,71(3):266-270
In this study, we present data on reproductive parameters and birth seasonality of Guizhou snub‐nosed monkeys (Rhinopithecus brelichi). Our analyses are based on data from a small captive population collected over 15 years and on 5 years of observations of free‐ranging snub‐nosed monkeys. Captive females (n=4) mature at an age of 70.8±6.7 months and reproduce for the first time at 103.4±7.5 months. The mean interbirth interval was 38.2±4.4 months if the infant survived more than 6 months, which is longer than that in R. roxellana and R. bieti. In the wild and in captivity, births are very seasonal and occur only in a period from the end of March to the end of April. Our data suggest that population growth in Guizhou snub‐nosed monkeys is slow compared with the other two Chinese snub‐nosed monkey species. The risk of extinction is therefore particularly high in this species, given the small overall population size and slow population recovery potential. Am. J. Primatol. 71:266–270, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
62.
YenDun Tony Tzeng KuanHao Tsui LingMing Tseng MingFeng Hou PeiYi Chu Jim JinnChyuan Sheu ChiaJung Li 《Journal of cellular and molecular medicine》2022,26(14):4007
The discovery of early diagnosis and prognostic markers for breast cancer can significantly improve survival and reduce mortality. LSM1 is known to be involved in the general process of mRNA degradation in complexes containing LSm subunits, but the molecular and biological functions in breast cancer remain unclear. Here, the expression of LSM1 mRNA in breast cancer was estimated using The Cancer Genome Atlas (TCGA), Oncomine, TIMER and bc‐GenExMiner databases. We found that functional LSM1 inactivation caused by mutations and profound deletions predicted poor prognosis in breast cancer (BRCA) patients. LSM1 was highly expressed in both BRCA tissues and cells compared to normal breast tissues/cells. High LSM1 expression is associated with poorer overall survival and disease‐free survival. The association between LSM1 and immune infiltration of breast cancer was assessed by TIMER and CIBERSORT algorithms. LSM1 showed a strong correlation with various immune marker sets. Most importantly, pharmacogenetic analysis of BRCA cell lines revealed that LSM1 inactivation was associated with increased sensitivity to refametinib and trametinib. However, both drugs could mimic the effects of LSM1 inhibition and their drug sensitivity was associated with MEK molecules. Therefore, we investigated the clinical application of LSM1 to provide a basis for sensitive diagnosis, prognosis and targeted treatment of breast cancer. 相似文献
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66.
Marianna Giannini Martina Giannaccini Teresa Sibillano Cinzia Giannini Dun Liu Zhigang Wang Andrea Baù Luciana Dente Alfred Cuschieri Vittoria Raffa 《PloS one》2014,9(12)
All biomaterials initiate a tissue response when implanted in living tissues. Ultimately this reaction causes fibrous encapsulation and hence isolation of the material, leading to failure of the intended therapeutic effect of the implant. There has been extensive bioengineering research aimed at overcoming or delaying the onset of encapsulation. Nanotechnology has the potential to address this problem by virtue of the ability of some nanomaterials to modulate interactions with cells, thereby inducing specific biological responses to implanted foreign materials. To this effect in the present study, we have characterised the growth of fibroblasts on nano-structured sheets constituted by BaTiO3, a material extensively used in biomedical applications. We found that sheets of vertically aligned BaTiO3 nanotubes inhibit cell cycle progression - without impairing cell viability - of NIH-3T3 fibroblast cells. We postulate that the 3D organization of the material surface acts by increasing the availability of adhesion sites, promoting cell attachment and inhibition of cell proliferation. This finding could be of relevance for biomedical applications designed to prevent or minimize fibrous encasement by uncontrolled proliferation of fibroblastic cells with loss of material-tissue interface underpinning long-term function of implants. 相似文献
67.
巴旦杏花物候学与形态学研究 总被引:11,自引:3,他引:11
观察研究了喀什地区4个巴旦杏主栽品种的开花物候期,开花习性,花及花粉的形态特征等内容,结果表明:巴旦杏花期始于3月下旬或4月上旬,花期持续约10-20d,4个主栽品种花期相遇;品种间花的形态丰在差异,早开的花花质较好,晚开的花畸形花百分率较高,供试品种的花粉粒在扫描电镜下存在微形态上的差异。 相似文献
68.
The Helicoverpa armigera nucleopolyhedrovirus (HearNPV) ORF80 (ha80) has 765 bp encoding a protein with approximately 254 amino acids and a predicted molecular weight of 30.8 kDa. Homologues of ha80 are found in most baculovirus sequences, including those from lepidopteran NPVs, lepidopteran granuloviruses (GVs), hymenopteran baculoviruses, and one dipteran baculovirus, yet their functions remain unclear. In this study we characterized ha80, and showed that it was transcribed late in infected host cells (HzAM1). The product of ha80 was a 31 kDa protein that was not a structural protein of budded virus (BV) or occlusion-derived virus (ODV) particles. Ha80 was first detected in the cytoplasm of infected HzAM1 cells at 12 h p.i., and was observed in the nucleus at later stages of infection, suggesting that it may be involved in transporting viral proteins into the host cell nucleus or play its roles in the nucleus. 相似文献
69.
Dunér K Bäckström J Magnell N Svennberg H Ahnoff M Logren U 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,852(1-2):317-324
An analytical method was developed for the determination of ximelagatran, an oral direct thrombin inhibitor, its active metabolite melagatran, and the two intermediate metabolites, OH-melagatran and ethyl-melagatran in human plasma. Extraction of plasma was carried out on a mixed mode bonded sorbent material (C8/SO(3)(-)). All four analytes, including their isotope-labelled internal standards, were eluted at high ionic strength with a mixture of 50% methanol and 50% buffer (0.25 M ammonium acetate and 0.05 M formic acid, pH 5.3) with an extraction recovery above 80%. The extracts were demonstrated to be clean in terms of a low concentration of albumin and lysoPC. The sample extraction was fully automated and performed in 96-well plates using a Tecan Genesis pipetting robot. Analysis of the extracts were performed with liquid chromatography followed by positive electrospray ionization mass spectrometry. The low organic content and the low pH of the extracts allowed for, after dilution 1:3 with buffer, direct injection onto the LC-column. The four analytes were separated on a C18 analytical LC-column using gradient elution with the acetonitrile concentration varying from 10 to 30% (v/v) and the ammonium acetate and acetic acid concentration kept constant at 10 and 5 mmol/L, respectively, at a flow rate of 0.75 mL/min. Linearity was achieved over the calibrated range 0.010-4.0 micromol/L with accuracy and relative standard deviation in the range 96.9-101.2% and 6.6-17.1%, respectively at LLOQ, and in the range 94.7-102.6% and 2.7-6.8%, respectively at concentrations above 3 x LLOQ. The method replaces a manual method, and displays the advantages of having a fully automated sample clean-up, no evaporation/reconstitution step, high recovery, and complete LC-separation of all four analytes. 相似文献
70.
Dun Y Mysona B Van Ells T Amarnath L Ola MS Ganapathy V Smith SB 《Cell and tissue research》2006,324(2):189-202
The cystine-glutamate exchanger, system xc
−, mediates the Na+-independent exchange of cystine into cells, coupled to the efflux of intracellular glutamate. System xc
− plays a critical role in glutathione homeostasis. Early studies of brain suggested that system xc
− was present primarily in astrocytes but not neurons. More recent work indicates that certain brain neurons have an active system xc
−. In the retina, system xc
− has been demonstrated in Müller and retinal pigment epithelial cells. We have recently suggested that two protein components of system xc
−, xCT and 4F2hc, are present in ganglion cells of the intact retina. Here, we have used (1) molecular and immunohistochemical assays to determine whether system xc
− is present in primary ganglion cells isolated from neonatal mouse retinas and (2) functional assays to determine whether its activity is regulated by oxidative stress in a retinal ganglion cell line (RGC–5). Primary mouse ganglion cells and RGC–5 cells express xCT and 4F2hc. RGC–5 cells take up [3H]glutamate in the absence of Na+, and this uptake is blocked by known substrates of system xc
− (glutamate, cysteine, cystine, quisqualic acid). Treatment of RGC–5 cells with NO and reactive oxygen species donors leads to increased activity of system xc
− associated with an increase in the maximal velocity of the transporter with no significant change in the substrate affinity. This is the first report of system xc
− in primary retinal ganglion cells and RGC–5 cells. Oxidative stress upregulates this transport system in RGC–5 cells, and the process is associated with an increase in xCT mRNA and protein but no change in 4F2hc mRNA or protein. This work was supported by National Institutes of Health grants EY014560 and EY012830. 相似文献