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The placenta of a pangolin, Manis tetradactyla, was examined grossly and histologically. The placenta was arranged in longitudinal bands of 2–3 mm width. Microscopically there was a deep labyrinth and an underlying layer of distended endometrial glands. A narrow junctional zone was present containing syncytiotrophoblast. Thoughout the labyrinth cytotrophoblast and syncytiotrophoblast were observed in contact with maternal capillaries. The placentation was considered to be endotheliochorial in type.  相似文献   
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When airways constrict, the surrounding parenchyma undergoesstretch and distortion. Because of the mechanical interdependence between airways and parenchyma, the material properties of the parenchyma are important factors that modulate the degree ofbronchoconstriction. The purpose of this study was to investigate theeffect of changes in transpulmonary pressure (Ptp) and inducedconstriction on parenchymal bulk (k)and shear (µ) moduli. In excised rat lungs, pressure was measured atthe airway opening, and pressure-volume curves were obtained byimposing step decreases in volume with a calibrated syringe from totallung inflation. Calculation was made ofk during small-volume oscillations (1 Hz). Absolute lung volume at 0 cmH2O Ptp was obtained bysaline displacement. To calculate µ, a lung-indentation test wasperformed. The lung surface was deformed with a cylindrical punch(diameter = 0.45 cm) in 0.25-mm increments, and the force required toeffect this displacement was measured by a weight balance. Measurementsof k and µ were obtained at 4 and 10 cmH2O Ptp, and again at 4 cmH2O Ptp, after delivery ofmethacholine aerosol (100 mg/ml) into the trachea. Values ofk and µ in rat lungs were similar tothose reported in other species. In addition, k and µ were dependent on Ptp. Afterinduced constriction, k and µ increased significantly. That k and µ can increase after induced constriction has important implicationsvis a vis the factors modulating airway narrowing.

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To meet product quality and cost parameters for therapeutic monoclonal antibody (mAb) production, cell lines are required to have excellent growth, stability, and productivity characteristics. In particular, cell line generation stability is critical to the success of a program, especially where high cell line generation numbers are required for large in‐market supply. However, a typical process for developing such cell lines is laborious, lengthy, and costly. In this study, we applied a FLP/FRT recombinase‐mediated cassette exchange (RMCE) system to build a site‐specific integration (SSI) system for mAb expression in the commercially relevant CHOK1SV cell line. Using a vector with a FRT‐flanked mAb expression cassette, we generated a clonal cell line with good productivity, long‐term production stability, and low mAb gene‐copy number indicating the vector was located in a ‘hot‐spot.’ A SSI host cell line was made by removing the mAb genes from the ‘hot‐spot’ by RMCE, creating a ‘landing pad’ containing two recombination cassettes that allow targeting of one or two copies of recombinant genes. Cell lines made from this host exhibited excellent growth and productivity profiles, and stability for at least 100 generations in the absence of selection agents. Importantly, while clones containing two copies had higher productivity than single copy clones, both were stable over many generations. Taken together, this study suggests the use of FLP‐based RMCE to develop SSI host cells for mAb production in CHOK1SV offers significant savings in both resources and overall cell line development time, leading to a shortened ‘time‐to‐clinic’ for therapeutic mAbs. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1645–1656, 2015  相似文献   
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The role of chemokines has been extensively analyzed both in cancer risk and tumor progression. Among different cytokines, CXCR4 and its ligand CXCL12 have been recently subjected to a closer examination. The single-nucleotide polymorphism (SNP) rs1801157 (previously known as CXCL12-A/SDF1-3'A) in the CXCL12 gene and the relative expression of mRNA CXCL12 in peripheral blood were assessed in breast cancer patients, since the chemokine CXCL12 and its receptor CXCR4 regulate leukocyte trafficking and many essential biological processes, including tumor growth, angiogenesis and metastasis of different types of tumors. Genotyping was performed by PCR-RFLP (polymerase chain reaction followed by restriction fragment length polymorphism) using MspI restriction enzyme and the expression analyses by quantitative RT-PCR. No difference in GG genotype and allele A carrier frequencies were observed between breast cancer patients and healthy blood donors and nor when CXCL12 mRNA expression was assessed among patients with different tumor stages. However a significant difference was observed when CXCL12 mRNA relative expression was analyzed in breast cancer patients in accordance to the presence or absence of the CXCL12 rs1801157 allele A. Allele A breast cancer patients presented a mRNA CXCL12 expression about 2.1-fold smaller than GG breast cancer patients. Estrogen positive patients presenting CXCL12 allele A presented a significantly lower expression of CXCL12 in peripheral blood (p=0.039) than GG hormone positive patients. Our findings demonstrated that allele A is associated with low expression of CXCL12 in the peripheral blood from ER-positive breast cancer patients, which suggests implications on breast cancer clinical outcome.  相似文献   
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