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21.
目的:了解烧伤病区铜绿假单胞菌(Pseudomonas aeruginosa,PA)感染的分子流行病学特征。方法:采用脉冲场凝胶电泳(PFGE)分型的方法,对15株分离自烧伤临床病人的多重耐药PA染色体组DNA进行分析。结果:15株检测菌株中有9株菌分别属于两种不同的PFGE图谱类型,具有同源性的菌株占测试菌株的60%。结论:导致我院烧伤患者感染多重耐药的PA中有同源性的比例较高,提示在烧伤救治中采取有针对性的措施,防止烧伤病房内的交叉感染对于降低烧伤感染率、提高烧伤救治水平具有重要意义。 相似文献
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Triploid origin of the gibel carp as revealed by 5S rDNA localization and chromosome painting 总被引:2,自引:0,他引:2
5S ribosomal DNA (rDNA) was isolated and sequenced from the gibel carp Carassius auratus gibelio with 162 chromosomes and crucian carp Carassius auratus with 100 chromosomes, and fluorescent probes for chromosome localization were prepared to ascertain the ploidy origin and
evolutionary relationship between the two species. Using fluorescence in-situ hybridization (FISH), major 5S rDNA signals were localized to the short arms of three subtelocentric chromosomes in the gibel
carp and to the short arms of two subtelocentrics in the crucian carp. In addition, some minor signals were detected on other
chromosomes of both species. Simultaneously, six chromosomes were microdissected from the gibel carp metaphase spreads using
glass needles, and the isolated chromosomes were amplified in vitro by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR). Significantly, when the DOP-PCR-generated probes
prepared from each single chromosome were hybridized, three same-sized chromosomes were painted in each gibel carp metaphase,
whereas only two painted chromosomes were observed in each crucian carp metaphase spread. The data indicate that gibel carp
is of triploid origin in comparison with diploid crucian carp. 相似文献
24.
S. Savi M. Savi S. Tamburi G. Vuleta S. Vesi C.C. Müller-Goymann 《European journal of pharmaceutical sciences》2007,30(5):441-450
There is a growing need for research into new skin- and environment-friendly surfactants. This paper focuses on a natural surfactant of an alkylpolyglucoside type, which can form both thermotropic and lyotropic liquid-crystalline phases. The aim of this study was to relate some physicochemical properties (characterised by polarisation and transmission electron microscopy, thermal analysis and rheology) of the three formulations based on cetearyl glucoside and cetearyl alcohol, to the results of in vitro and in vivo bioavailability of hydrocortisone (HC). The three formulations contained oils of different polarity (medium chain triglycerides: MG, isopropyl myristate: IPM and light liquid paraffin: LP), respectively. In vitro permeation was followed through the artificial skin constructs (ASC), while the parameters measured in vivo were erythema index: EI (using instrumental human skin blanching assay), transepidermal water loss (TEWL) and stratum corneum hydration (SCH). The vehicles based on cetearyl glucoside and cetearyl alcohol showed a complex colloidal structure of lamellar liquid-crystalline and lamellar gel-crystalline type, depending on oil polarity. Rheological profile of the vehicle was directly related to the in vitro profile of the HC permeation. In vivo results suggested that the vehicle with MG retarded the HC permeation, whereas less polar IPM and non-polar LP enhanced it. It is suggested that the enhancement is achieved either by a direct interaction with lipid lamellae of the SC or indirectly by improving skin hydration.
There were no adverse effects during in vivo study, which indicates a good safety profile of this alkylpolyglucoside surfactant. 相似文献
25.
Soonmyoung Paik M.D. 《Breast cancer research and treatment》1992,22(1):31-38
Summary Expression of IGF-I and IGF-II was studied in human breast cancer tissues by in situ hybridization. IGF-I mRNA was detected only in stromal cells adjacent to normal breast epithelial cells. Stromal cells associated with the tumor cells did not contain IGF-I, nor did malignant or benign breast epithelial cells. In contrast, IGF-II mRNA was found in both the malignant epithelial cells and their adjacent stromal cells. These data imply that stromal cells associated with breast epithelium may switch expression from IGF-I to IGF-II during breast cancer evolution. This appearance of IGF-II expression may identify cancer-associated stromal cells that have a fetal phenotype. 相似文献
26.
从制备方法着手综述了近年来聚苯胺/聚合物导电材料研制开发的最新成果,并简介了聚苯胺/聚合物导电材料的应用情况。 相似文献
27.
The relationship between high-density-lipoprotein (HDL) particle size subclasses and the levels of the major lipoprotein lipids was studied in 74 men consecutively referred to the lipid clinic. HDL (density 1.070-1.21 kg l-1) was separated by polyacrylamide gradient gel electrophoresis (GGE) into five size-defined subclasses, in order of decreasing size as follows: HDL2b, HDL2a, HDL3a, HDL3b and HDL3c. Cholesterol and triglyceride concentrations in very-low-density (VLDL), low-density (LDL) and high-density (HDL) lipoproteins were determined. The level of VLDL triglycerides was negatively correlated with HDL2b (r = -0.66, P less than 0.0001), and positively correlated with HDL3b concentrations (r = 0.65, P less than 0.0001). Both correlations were restricted to subjects with VLDL triglyceride concentrations of less than 1.80 mmol l-1, i.e. those with normotriglyceridaemia. Patients with a history of myocardial infarction and/or angina pectoris (n = 18) had significantly lower HDL2b levels than subjects with asymptomatic hyperlipidaemia (n = 50), i.e. 0.16 vs. 0.22 mg protein ml-1 (P less than 0.05), despite essentially similar cholesterol and triglyceride levels in the VLDL, LDL and HDL fractions, including HDL2 and HDL3 cholesterol. 相似文献
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29.
High Cell-Density Culture System of Hepatocytes Entrapped in a Three-Dimensional Hollow Fiber Module with Collagen Gel 总被引:2,自引:0,他引:2
Kazuyoshi Takeshita Haruaki Ishibashi Masayuki Suzuki Takumi Yamamoto Toshihiro Akaike Masashi Kodama 《Artificial organs》1995,19(2):191-193
Abstract: A compact three-dimensional (3D) module is needed for hepatocyte culture in order to develop an effective hybrid artificial liver system that can retain hepa-tocellular structure and differentiated functions. We treated the 3D module with collagen gel to entrap rat hepatocytes. This method yielded a high hepatocellular density (2 times 107 cells/ml) over a period of 14 days and maintained the secretion of albumin and ureogenesis at the same level as the control monolayer method. The ammonia removal remained at 43% of the Day 0 value over 8 days of perfusion. Our data show that this approach may be useful for liver support therapy in an ex-tracorporeal circuit. 相似文献
30.
A review of in-situ EBSD experiments 总被引:4,自引:1,他引:3
IntroductionIn the firstautomated Electron Backscatter Diffrac-tion(EBSD)[1]or Orientation Imaging Microscopy(OIM)[2]systems,patterns were indexed at a rate ofabout four seconds per pattern.In the past decade,OIMscan speeds have increased to over 300 times fas-ter than the original measurements.During this sametime period,scanning electron microscope(SEM)technology has also seen large improvements enablingthe OIMtechnique to be applied at higher spatial reso-lutions and with more flex… 相似文献