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992.
CC Cheng N Lu CL Peng CC Chang FD Mai LY Chen MH Liao WM Wang J Chang 《Proteomics》2012,12(15-16):2584-2597
The survivals of gastric cancer (GC) patients are associated with early diagnosis and effective treatments. Therefore, it is urgent for the discovery of early GC biomarkers and tumor-targeting therapeutics. The aim of this study was to uncover putative tissue biomarkers of GC using 2D DIGE and then apply one of these specific markers in GC treatment. We found three putative biomarkers of GC with significant differences in expression level compared to adjacent normal tissue, including glucose-regulated protein 78 (GRP78) and glutathione s-transferase pi (GSTpi) with increased expression level, and alpha-1 antitrypsin (A1AT) with reduced expression level. The overexpressed GRP78 was used as a targeted protein for guiding the drugs to tumor cells, leading to more effective treatment for GC xenografts. Our results demonstrated that the designated GRP78-binding peptide based on the sequence, WIFPWIQL, was selectively prone to recognize and bind to GC MKN45 cells in vitro, and also improve the delivery efficiency of polymeric micelles-encapsulated drugs into tumor cells and displayed better therapeutic outcome in experimental animals. This strategy of GRP78-mediated drug targeting system may bring chemotherapeutic drugs with more precise targeting to tumor cells, leading to minimize side effects on patients after chemotherapy. 相似文献
993.
Self-assembly reaction of Cd(ClO4)2 · 6H2O with Norfloxacin (H-Norf) affords a novel 2D rectangular grid framework [Cd(Norf)(ClO4)(H2O)] (1) with strong blue luminescent emission (λem=425 nm), while Norf− acts as a tetradentate bridging linker to connect three Cd centers and ClO4 − completes Cd center octahedron coordination geometry. The compound 1 has crystallographic data of triclinic, space group , a=9.4577(1) Å, b=9.5012(2) Å, c=12.2805(1) Å, V=3624.4(3) Å3, Z=2. 相似文献
994.
Liu Zhensheng Wang Xiaoming Li Zhigang Cui Duoying Li Xinqing 《Frontiers of Biology in China》2007,2(1):100-107
The feeding habitat selection of blue sheep (Pseudois nayaur) was studied by direct observation method in the Helan Mountains, China during winter (from November to December) and spring
(from April to June) from 2003 to 2004. We established 25 line transects to collect information on feeding habitats used by
blue sheep. Blue sheep in the study area preferred mountain savanna forests, a habitat dominated by Ulmus glaucescens, with medium tree density (<4 individuals / 400 m2), moderate tree height (4–6 m), higher shrub density (> 5 individuals / 100 m2), higher shrub (> 1.3 m), higher food abundance (> 50 g), moderate distance to human disturbance (< 500 m), and mild distance
to bare rock (< 2 m). Such habitats characterized by 12 ecological factors were preferred as feeding areas by blue sheep during
winter. Similar to habitat selection by the species during winter, blue sheep also showed a preference for mountain savanna
with tree dominated by Ulmus glaucescens and medium tree density (< 4 individuals / 400 m2) during spring. Nevertheless, blue sheep preferred medium tree height (< 6 m), moderate tree density (5–10 individuals /
100 m2), medium shrub height (1.3–1.7 m), higher food abundance (> 100 g), moderate altitude (< 2 000 m), moderate distance to water
resource (< 500 m), and medium hiding cover (50%–75%) during spring. Selection of the feeding habitats by sheep showed a significant
difference in vegetation type, landform feature, dominant tree, tree height, shrub density, distance to the nearest shrub,
food abundance, slope direction, slope degree, distance to water resource, and hiding cover between winter and spring. Results
of principal components analysis indicated that the first principal component accounted for 24.493% of the total variance
among feeding habitat variance during winter, with higher loadings for vegetation type, dominant tree, tree height, distance
to the nearest tree, shrub density, shrub height, altitude, distance to water resource, and distance to human disturbance.
In spring, the first principal components explained 28.777% of the variance, with higher loadings for vegetation type, distance
to the nearest tree, shrub height, distance to the nearest shrub, food abundance, altitude, and distance to human disturbance.
Translated from Zoological Research, 2005, 26(6): 580–589 [译自: 动物学研究] 相似文献
995.
Identifying the ecological environment suitable for the growth of Thuja sutchuenensis and predicting other potential distribution areas are essential to protect this endangered species. After selecting 24 environmental factors that could affect the distribution of T. sutchuenensis, including climate, topography, soil and Normalized Difference Vegetation Index (NDVI), we adopted the Random Forest-MaxEnt integrated model to analyze our data. Based on the Random Forest study, the contribution of the mean temperature of the warmest quarter, mean temperature of the coldest quarter, annual mean temperature and mean temperature of the driest quarter was large. Based on MaxEnt model prediction outputs, the potential distribution map not only identified areas that originally recorded T. sutchuenensis, such as Xuanhan County, Kai County and Chengkou County, but also identified highly suitable distribution areas where T. sutchuenensis may exist, including Wanyuan County, Sichuan Province, and the junction of Chongqing and Hubei Province. This provides a more explicit geographic range for ex situ conservation and reintroduction of T. sutchuenensis. Our results also indicate that, in addition to climate factors, topography and soil factors are also important environmental factors that affect distribution. This provides a theoretical basis for subsequent laboratory construction to simulate the indoor growth of T. sutchuenensis. 相似文献
996.
Preparation of cross-linked carboxymethyl chitosan for repairing sciatic nerve injury in rats 总被引:1,自引:0,他引:1
A successful nerve regeneration process was achieved with nerve repair tubes made up of 1-ethyl-3(3-dimethylaminopropyl) carbodiimide
hydrochloride (EDC) cross-linked carboxymethyl chitosan (CM-chitosan) with improved biodegradability. Chitosan has a very
slow degradation rate, while the EDC cross-linked CM-chitosan tubes degraded to 30% of original weight during 8 weeks of incubation
in lysozyme solution. In vitro cell culture indicated that the CM-chitosan films presented no cytotoxicity to Schwann cells.
From in vivo studies using a 10 mm rat sciatic nerve defect model investigated by histomorphometry analysis, the average diameter
of the fibers and the average thickness of myelin sheath in the CM-chitosan tubes were 3.7 ± 0.33 and 0.33 ± 0.04 μm, respectively,
which demonstrated equivalence to nerve autografts (the current “gold” standard); furthermore, the average fiber density in
the CM-chitosan tubes was 20.5 × 103/mm2, which was similar to that of autografts (21 × 103/mm2) and significantly higher than that of common chitosan tubes (15.3 × 103/mm2). 相似文献
997.
S. Wang F. Ding R. Zhao R. Li L. Zhang Y. Liu F. Gao L. Wang Y. Dai N. Li 《Theriogenology》2009,72(4):535-541
Introduction of selectable marker genes to transgenic animals could create an inconvenience to further research and may exaggerate public concerns regarding biological safety. The objective of the current study was to excise loxP flanked neoR in transgenic cloned cattle by transient expression of Cre recombinase. Green fluorescent protein gene (GFP) was incorporated to monitor Cre expression; therefore, Cre-expressed cells could be selected indirectly by fluorescence-activated cell sorting (FACS). The neoR was removed and Cre expressed transiently in GFP-positive colonies; excision of neoR was confirmed by single-blastocyst PCR in recloned blastocysts, with neoR-free fibroblast cells as donors. There was no difference (P > 0.05) in rates of cleavage (76.0% vs. 68.8%) or blastocyst formation (56.6% vs. 52.9%) between recloned embryos with neoR-free or neoR-included donors. The differential staining of recloned blastocysts were similar (P >0.05) in terms of total cell number (124 vs. 122) and the ratio of ICM (Inner Cell Mass) to the total cell number (38.1% vs. 38.2%). Furthermore, pregnancy and calving rates were not different (P > 0.05) from those of the control. In conclusion, we successfully excised neoR from transgenic cloned cattle; the manipulation did not affect the developmental competence of recloned preimplantation embryos. This approach should benefit bioreactor and transgenic research in livestock. 相似文献
998.
葛根素对血管性痴呆大鼠海马突触传递长时程增强的影响 总被引:1,自引:0,他引:1
目的:探讨葛根素对血管性痴呆大鼠长时程增强(LTP)的影响。方法:采用Morris水迷宫和LTP诱导法检测血管性痴呆模型大鼠空间学习记忆能力和海马突触传递的改变。结果:模型组大鼠不同时间点测得的Morris水迷宫逃逸潜伏期均较假手术组明显延长,海马LTP诱导率明显降低,而药物组大鼠EL均短于模型组,但LTP诱导率明显增强。结论:葛根素可增强血管性痴呆大鼠突触传递功能,改善其长期存在的学习记忆障碍。 相似文献
999.
对TMV不同抗性番茄品种的叶绿体DNA限制性内切酶酶谱分析 总被引:1,自引:0,他引:1
选用对TMV有抗性和敏感的番茄品种、制备其ct-DNA, 用限制性内切酶BumHI、EcoRI和PstI完全酶解, 三种酶切图谱与前人报道一致, 由酶切片段计算番茄ct-DNA。分子量约为156.9kb。比较抗性和敏感品种的ct-DNA图谱, 发现三种酶切图谱均存在差异, 但由差异片段计算分子量之和又很除近。我们推测这是由于检基顺序变异或小段DNA顺序插入或缺失所造成, 由此证明, 叶绿体基因组与核中的TMV抗性基因, 共同决定着植物体对TMV的抗性。 相似文献
1000.
鱼腥藻提取液对水稻生长发育和产量的促进作用 总被引:1,自引:1,他引:1
以田间小区试验和大区产量直接对比的方法研究了鱼腥藻提取认对水稻幼苗生长和产量以及产量构成要素的影响,并探讨了方便有效且适宜于大田使用的方法。用藻液处理后水稻幼苗增高,根数、根长增加,分蘖能力增强,秧龄提前,叶面积明显加大。水稻成熟后除株高比对照略有下降外,各项产量构成要素如粒数、粒重、有效分蘖数、植株干重、千粒重、穗长等都优于对照组,但增产幅度随水稻品种和处理方式不同而异。大田使用时以1%鱼腥藻提 相似文献