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61.
随着我国老龄化进程的进一步加剧,衰弱作为常见的老年综合征已成为备受关注的公共卫生问题。高血压与衰弱常共存于老年人,导致出现多种不良健康结局。本文分析了老年高血压相关性衰弱的流行现状及发病机制,包括炎性反应、氧化应激反应、胰岛素抵抗及激素代谢紊乱等,总结了运动干预改善高血压相关性衰弱的可能作用途径,并发现目前关于高血压相关性衰弱的运动作用机制类研究仍然缺乏,而且不同类型的运动干预形式对机体的作用机制也存在一定差异性,未来可以进一步探讨不同的运动干预形式对高血压相关性衰弱的作用靶点及干预效果的不同。 相似文献
62.
63.
Cells are known to be surrounded by nanoscale topography in their natural extracellular environment. The cell behavior, including morphology, proliferation, and motility of bovine pulmonary artery smooth muscle cells (SMC) were studied on poly(methyl methacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) surfaces comprising nanopatterned gratings with 350 nm linewidth, 700 nm pitch, and 350 nm depth. More than 90% of the cells aligned to the gratings, and were significantly elongated compared to the SMC cultured on non-patterned surfaces. The nuclei were also elongated and aligned. Proliferation of the cells was significantly reduced on the nanopatterned surfaces. The polarization of microtubule organizing centers (MTOC), which are associated with cell migration, of SMC cultured on nanopatterned surfaces showed a preference towards the axis of cell alignment in an in vitro wound healing assay. In contrast, the MTOC of SMC on non-patterned surfaces preferentially polarized towards the wound edge. It is proposed that this nanoimprinting technology will provide a valuable platform for studies in cell-substrate interactions and for development of medical devices with nanoscale features. 相似文献
64.
应用放射配体结合法证实大鼠胸腺内存在降黑素特异结合部位,该结合位点可以满足特异结合部位的基本条件:1.低结合容量;2.高亲和力;3.可饱和性;4.可逆性;5.对降黑素高度特异性。此外,该特异结合位点具昼夜节律;亚细胞分布的研究表明以细胞核含量最高,线粒体次之,并具有年龄依赖性降低,以出生时最高。 相似文献
65.
Epidemiologic analysis of sporadic Salmonella typhi isolates and those from outbreaks by pulsed-field gel electrophoresis. 总被引:9,自引:7,他引:9
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K L Thong Y M Cheong S Puthucheary C L Koh T Pang 《Journal of clinical microbiology》1994,32(5):1135-1141
Pulsed-field gel electrophoresis (PFGE) was used to compare and analyze 158 isolates of Salmonella typhi from five well-defined outbreaks of typhoid fever in Malaysia and also isolates involved in sporadic cases of typhoid fever occurring during the same period. Digestion of chromosomal DNAs from these S. typhi isolates with the restriction endonucleases XbaI (5'-TCTAGA-3'), SpeI (5'-ACTAGT-3'), and AvrII (5'-CCTAGG-3') and then PFGE produced restriction endonuclease analysis (REA) patterns consisting of 11 to 24 DNA fragments ranging in size from 20 to 630 kbp. Analysis of the REA patterns generated by PFGE after digestion with XbaI and SpeI indicated that the S. typhi isolates obtained from sporadic cases of infection were much more heterogeneous (at least 13 different REA patterns were detected; Dice coefficient, between 0.73 and 1.0) than those obtained during outbreaks of typhoid fever. The clonal nature and the close genetic identities of isolates from outbreaks in Alor Setar, Penang, Kota Kinabalu, Johor Bahru, and Kota Bahru were suggested by the fact that only a limited number of REA patterns, which mostly differed by only a single band, were detected (one to four patterns; Dice coefficient, between 0.82 and 1.0), although a different pattern was associated with each of these outbreaks. Comparison of REA patterns with ribotyping for 18 S. typhi isolates involved in sporadic cases of infection showed a good correlation, in that 72% of the isolates were in the same group. There was no clear correlation of phage types with a specific REA pattern. We conclude that PFGE of s. typhi chromosomal DNA digested with infrequently cutting restriction endonucleases is a useful method for comparing and differentiating S. typhi isolates for epidemiological purposes. 相似文献
66.
目的 报告应激性溃疡的临床诊治体会。方法 全组16例,男12例,女4例。术前均无溃疡病史,血红蛋白检查均正常。术后早期应用糖皮质激素9例,出血前发生肺不张、严重呼吸道感染、呼吸功能不全6例,低血容量休克5例,急性重症出血坏死性胰腺炎4例,食管癌、贲门癌术后6例,严重烧伤(80%(?)Ⅱ°)1例。14例保守治疗,2例保守治疗无效而手术治疗。结果14例经治疗后(2例手术治疗)痊愈出院,2例死亡。结论 应激性溃疡大出血患者多病情危重,难以忍受二次手术,死亡率约为50%,因此应采取有效的保守治疗,对于保守治疗无效、大出血休克或胃肠穿孔者应及时手术治疗。 相似文献
67.
Comparison of LightCycler-based PCR,COBAS amplicor CMV monitor,and pp65 antigenemia assays for quantitative measurement of cytomegalovirus viral load in peripheral blood specimens from patients after solid organ transplantation 总被引:2,自引:0,他引:2
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Pang XL Chui L Fenton J LeBlanc B Preiksaitis JK 《Journal of clinical microbiology》2003,41(7):3167-3174
In order to evaluate the LightCycler-based PCR (LC-PCR) as a diagnostic assay technique, a classical pp65 antigenemia assay and the commercially available COBAS Amplicor CMV Monitor (CACM) assay were compared to the LC-PCR assay for the detection and quantitation of cytomegalovirus (CMV) load in 404 parallel specimens of peripheral blood from 66 patients after solid organ transplantation. A good correlation existed among these three assays (r congruent with 0.6, P < 0.0001). The LC-PCR assay was the most sensitive (54% of specimens positive) compared to the CACM (48.6%) and the pp65 antigenemia (26%) assays. The LC-PCR assay detected all samples found positive by using both the CMV pp65 antigenemia assay and the CACM assay. The LC-PCR also had the widest dynamic range (from 250 to 10(7) DNA copies/ml of plasma). No cross-reactions were found among CMV and Epstein-Barr virus, varicella-zoster virus, or herpes simplex virus in the LC-PCR by using amplification with specifically designed primer pairs. Precision, expressed as the coefficient of variation, was <3% with standard DNA from cell cultures and between 6.55 and 14.1% with clinical specimens in repeat LC-PCR runs. One run of the LC-PCR took half of the time required for the semiautomated CACM procedure. Because of its sensitivity, specificity, cost-effectiveness, and simplicity, the LC-PCR assay could replace the pp65 antigenemia and the CACM assays as the preferred technique for the surveillance, diagnosis, and monitoring of response of CMV diseases in high-risk populations. 相似文献
68.
In vivo expression and immunological studies of the 42-kilodalton carboxyl-terminal processing fragment of Plasmodium falciparum merozoite surface protein 1 in the baculovirus-silkworm system
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The 42-kDa carboxyl-terminal processing fragment of Plasmodium falciparum merozoite surface protein 1 (MSP-1(42)) is an anti-erythrocytic stage malaria vaccine candidate. In this study, MSP-1(42) was expressed by using the Bombyx mori nuclear polyhedrosis virus-silkworm expression system, and the antigenicity and immmunogenicity of the recombinant protein, Bmp42, were evaluated. The average yield of Bmp42, as determined by a sandwich enzyme-linked immunosorbent assay (ELISA), was 379 microg/ml of infected silkworm hemolymph, which was >100-fold higher than the level attainable in cell culture medium. N-terminal amino acid sequencing revealed that Bmp42 was correctly processed in silkworm cells. Data from immunoblotting, as well as from the inhibition ELISA, suggested that the conformational B-cell epitopes of MSP-1(42) were recreated in Bmp42. Immunization of rabbits with Bmp42 in complete Freund's adjuvant generated high-titer antibody responses against the immunogen. Specificity analyses of the anti-Bmp42 antibodies using several recombinant MSP-1(19) proteins expressing variant and conserved B-cell epitopes suggested that the anti-Bmp42 antibodies recognized primarily conserved epitopes on MSP-1(19). Furthermore, the anti-Bmp42 antibodies were highly effective in inhibiting the in vitro growth of parasites carrying homologous or heterologous MSP-1(42). Our results demonstrated that the baculovirus-silkworm expression system could be employed to express biologically and immunologically active recombinant MSP-1(42) at elevated levels; thus, it is an attractive alternative for producing a protective MSP-1(42) vaccine for human use. 相似文献
69.
倪晓莉 《国际中华应用心理学杂志》2006,3(1):56-57
目的研究社区老年人的心理健康状况及其心理卫生保健模式。方法采用心理调查问卷并进行统计分析,结果社区老年人心理健康水平与全国成人相比存在明显差异。结论本研究顾示,社区老年人心理健康问题突出,对此提出相应心理卫生保健模式以期改善老年人心理健康状况。 相似文献
70.
对铀作业者199例及无毒物接触史的正常人101例行甲襞微循环检测。结果,铀作业人员甲襞微循环有改变,其加权积分值大于对照组。主要表现在管袢数减少(P<0.01)、管径增粗(P<0.01)、毛细血管运动增加(P<0.01)、乳丛增多(P<0.01)。通过对铀致微循环改变的机理试以分析,提出这种微循环改变是铀中毒的病理表现,亦是铀中毒的重要发病环节;提示铀中毒治疗中应注重改善微循环。 相似文献