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991.
We isolated and characterized the highly polymorphic tetra-nucleotide microsatellite S0719 on SSC7q14-q15 adjacent to the porcine testis-specific phosphoglycerate kinase 2 (PGK2) gene and assigned it to the USDA-MARC linkage map on SSC7 position 77.5 cM closely linked to markers SW859 (76.3 cM) and SWR2036 (79.0 cM). In a panel of 344 individuals representing 11 pig breeds (European, Chinese, and North American), a total of 32 alleles were observed, and the overall breeds' calculated PIC (polymorphism information content), HE (heterozygosity), and NE (effective allele number) were 0.94, 0.94, and 16.41. Breed-specific PIC and HE ranged from 0.66 to 0.87, whereas NE was as low as 2.95 and as high as 7.96. Considering the high allelic variation of S0719 within and among pig breeds (79% of the genotyped animals were heterozygous), the marker is useful for individual animal identification and parentage determination. Finally, S0719 is also a valuable STS marker for fine-mapping QTL on SSC7 as position 77.5 cM is located in 25 QTL intervals (http://www.animalgenome.org/QTLdb/).  相似文献   
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993.
The receptor for the globular heads of C1q, C1qBP/gC1qR/p33, is a multicompartmental, multifunctional cellular protein with an important role in infection and in inflammation. In the present study, we identified and characterized the complement component 1q subcomponent binding protein (C1qBP) from the tiger shrimp Penaeus monodon (designated as PmC1qBP). The open reading frame of PmC1qBP encodes 262 amino acid residues with a conserved MAM33 domain, an arginine-glycine-aspartate cell adhesion motif, and a mitochondrial targeting sequence in the first 53 amino acids. PmC1qBP shares 32%–81% similarity with known C1qBPs and clusters with lobster gC1qR under phylogenetic analysis. The temporal PmC1qBP mRNA expression in the hepatopancreas was significantly enhanced at 9 h after Vibrio vulnificus challenge. The native PmC1qBP was expressed in the gills, hepatopancreas, ovaries, and intestines as a precursor (38 kDa) and the active peptide (35 kDa). The recombinant PmC1qBP protein was expressed in Escherichia coli BL21, and was purified using nickel–nitrilotriacetic acid agarose. A complement 1q binding assay indicated that the rC1qBP protein competitively binds to C1q in mouse serum. The data reveal that PmC1qBP is not only involved in shrimp immune responses to pathogenic infections, but also cross-binding to the mouse C1q.  相似文献   
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996.

Background

Wound healing is a complex biologic process that involves the integration of inflammation, mitosis, angiogenesis, synthesis, and remodeling of the extracellular matrix. However, some wounds fail to heal properly and become chronic. Although some simulated chronic wound models have been established, an efficient approach to treat chronic wounds in animal models has not been determined. The aim of this study was to develop a modified rat model simulating the chronic wounds caused by clinical radiation ulcers and examine the treatment of chronic wounds with adipose-derived stem cells.

Results

Sprague–Dawley rats were irradiated with an electron beam, and wounds were created. The rats received treatment with adipose-derived stem cells (ASCs), and a wound-healing assay was performed. The wound sizes after ASC treatment for 3 weeks were significantly smaller compared with the control condition (p < 0.01). Histological observations of the wound edge and immunoblot analysis of the re-epithelialization region both indicated that the treatment with ASCs was associated with the development of new blood vessels. Cell-tracking experiments showed that ASCs were colocalized with endothelial cell markers in ulcerated tissues.

Conclusions

We established a modified rat model of radiation-induced wounds and demonstrated that ASCs accelerate wound-healing.  相似文献   
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998.
Vertebrate-type steroids, such as progesterone, have been identified in crustaceans. The physiological activity of progesterone during vitellogenesis is still not well understood. In this study, progesterone levels in the female mud crab, Scylla paramamosain, were determined by enzyme-linked immunosorbent assay. Peak levels of progesterone were detected during the previtellogenic stage in the hemolymph, ovary, and hepatopancreas, whereas the progesterone level decreased significantly in vitellogenic stage I. During vitellogenic stage II, progesterone levels rose again in the hemolymph and ovary, but continued to decrease in the hepatopancreas. By using western blotting, progesterone receptor (PR), with an apparent molecular weight of 70 kDa, was identified in the ovary during both vitellogenic stages I and II. By means of immunohistochemistry, PR was detected mainly in the follicle cells during vitellogenic stage I and in the nuclei of oocytes in vitellogenic stage II. Our results strongly suggest that progesterone promotes vitellogenesis in the mud crab, S. paramamosain via a classical genomic mechanism.  相似文献   
999.
In this paper, an automated method to localise the right superficial femoral artery (SFA) and identify its boundary on magnetic resonance imaging (MRI) sequences without contrast medium injection is proposed. Some anatomical knowledge combined with the mathematical morphology is used to distinguish SFA from other vessels. Afterwards, the directional gradient, continuity and the local contrast are applied as features to identify the artery's boundary using dynamic programming. The accuracy analysis shows that the system has average unsigned errors 3.1 ± 3.1% on five sequences compared to experts' manual tracings.  相似文献   
1000.
Synthesis of (R)-2-trimethylsilyl-2-hydroxyl-propionitrile via asymmetric transcyanation of acetyltrimethylsilane with acetone cyanohydrin in an aqueous/organic biphasic system catalyzed by (R)-hydroxynitrile lyase from Prunus japonica seed meal was successfully carried out for the first time. The optimal volume ratio of aqueous to organic phase, buffer pH value and reaction temperature were 15% (v/v), 5.0 and 30°C, respectively, under which both substrate conversion and product enantiomeric excess (ee) were 99%. Silicon atom in the substrate showed great effect on the reaction. Acetyltrimethylsilane was a much better substrate for (R)-hydroxynitrile lyase from Prunus japonica than its carbon analogue.  相似文献   
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