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排序方式: 共有1045条查询结果,搜索用时 202 毫秒
1.
目的快速鉴定血培养中的金黄色葡萄球菌和凝固酶阴性葡萄球菌(CoNS),结合临床快速判定是否为污染菌。方法采用荧光原位杂交法鉴定血培养中的金黄色葡萄球菌和CoNS,杂交结果若为CoNS,根据临床资料进行判断,并与文献推荐的污染判断法进行结果比较。结果探针的特异性经由标准菌株和临床分离菌株证实。金黄色葡萄球菌探针的特异性和敏感性均为100%,GoNS探针的特异性和敏感性分别为100%和95.5%。179株CoNS中117株判断为污染菌,污染率为68%,与文献推荐的污染判断方法一致。结论荧光原位杂交法适用于血培养中的金黄色葡萄球菌和CoNS的快速鉴定,以排除CoNS污染。 相似文献
2.
偏头痛大鼠脑内5-羟色胺1F和诱导型一氧化氮合酶基因的表达变化及针刺的干预效应 总被引:3,自引:0,他引:3
目的:前期实验已证实针刺治疗偏头痛疗效优越。观察针刺对偏头痛大鼠脑内5-羟色胺1F和诱导型一氧化氮合酶mRNA表达的调控作用。方法:实验于2005-11/2006-05在中南大学湘雅医院中西医结合研究所实验室完成。①选用SD大鼠40只,按随机数字表法分为4组(n=10),除正常对照组外,其余3组均复制大鼠偏头痛模型。模型对照组只造模,不作其他处理;针刺治疗组造模后进行针刺;针刺预防组针刺后造模电刺激20min。针刺方法:针刺大鼠双侧太冲、阳陵泉穴20min。采用疏密波,电流强度0.3~0.6mA,留针20min,1次/d,共5次。②实验完毕后取脑干及三叉神经节匀浆,采用反转录-聚合酶链反应法测定5-羟色胺1F和诱导型一氧化氮合酶mRNA表达。结果:进入结果分析正常对照组10只,模型对照组、针刺治疗组、针刺预防组各9只,共脱失3只。①与正常对照组比较,模型对照组大鼠诱导型一氧化氮合酶mRNA表达显著增强(P<0.01),5-羟色胺1FmRNA表达显著减弱(P<0.01)。②与模型对照组比较,针刺预防组和针刺治疗组诱导型一氧化氮合酶mRNA表达明显减弱(P<0.01),5-羟色胺1FmRNA表达显著增强(P<0.01)。结论:针刺调控5-羟色胺1F和诱导型一氧化氮合酶mRNA的表达可能是针刺防治偏头痛的分子机制。 相似文献
3.
Levorphanol is a widely used opiate analgesic. Although structurally related to morphine, levorphanol has high affinity for a number of receptor subtypes, including both kappa 1 and kappa 3. Prior reports had implicated a kappa component of levorphanol-induced antinociception. Evidence is now presented suggesting that levorphanol-induced analgesia is produced by a mixture of mu and kappa 3 mechanisms. Levorphanol was a potent analgesic in the tail-flick assay, when given systemically, spinally or supraspinally. Isobolographic analysis of the combined administration of levorphanol, spinally and supraspinally implied synergistic interactions. Naloxonazine reduced levorphanol-induced analgesia, implicating a role for mu1 receptors. The kappa 1 antagonist nor-binaltorphimine at a dose which reversed analgesia induced by U50,488H did not antagonize levorphanol-induced analgesia. Additional studies revealed no cross tolerance in either direction, between levorphanol with the kappa 1 analgesic U50,488H. Together, these results strongly argue against a role for kappa 1 receptors in levorphanol-induced analgesia. However, mice tolerant to the kappa 3 analgesic, naloxone benzoylhydrazone (NalBzoH), showed cross tolerance to levorphanol, implying a role of kappa 3 mechanisms in levorphanol-induced analgesia. 相似文献
4.
Increased sensitivity of virus-infected cells to inhibitors of protein synthesis does not correlate with changes in plasma membrane permeability 总被引:3,自引:0,他引:3
J M Cameron M J Clemens M A Gray D E Menzies B J Mills A P Warren C A Pasternak 《Virology》1986,155(2):534-544
Semliki Forest virus-infected BHK cells or herpes simplex virus-infected Vero cells were incubated with the protein synthesis inhibitors hygromycin B and gougerotin. Infected cells take up no more [3H]hygromycin or [3H]gougerotin than do mock-infected cells, at a time p.i. at which either compound is more inhibitory to protein synthesis in infected, than in mock-infected cells. The concentrations of hygromycin and gougerotin required to inhibit protein synthesis in intact cells (irrespective of whether they are infected or not) are several orders of magnitude higher than those required in either permeabilized cells or in cell-free systems. Infected cells take up 86Rb+ at the same rate as mock-infected cells, their intracellular content of K+ is the same, and the activity of the Na+ pump is the same. It is concluded that the increased efficacy of hygromycin and gougerotin in virus-infected cells is a consequence of altered intracellular compartmentation and that increases in permeability of the plasma membrane, if any, are so small as to be undetectable by direct methods. 相似文献
5.
Retrorenal colon: implications for percutaneous diskectomy 总被引:1,自引:0,他引:1
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary. 相似文献
6.
The number of colony-forming cells (CFC) in the peripheral blood (PB) of 43 volunteers was examined using a semisolid clonogenic
culture assay. In all, 22 male (age 21–39 years) and 21 female individuals (age 21–39 years) were tested, ten of each group
twice to examine the intraindividual variability of colony-forming cells in PB. A statistically significant sex difference
in the number of CFC, erythroblastic colonies (BFU-E), and granulocyte/macrophage colonies (CFU-GM) in PB was detected in
favor of male individuals. No significant difference between female and male PB was found for the number of CFU-GEMM. The
intraindividual variability of CFC and BFU-E was significantly higher in female donors. These results support previous reports
by others on a potential influence of sex steroids on hematopoiesis.
Received: 8 November 1996 / Accepted: 4 April 1997 相似文献
7.
8.
Background
Physicians' awareness of their important role in defusing the obesity epidemic has increased. However, the number of family practitioners who treat obesity problems continues to be low. Self-efficacy refers to the belief in one's ability to organize and execute the courses of action required to produce given attainments. Thus, practitioners who judge themselves incapable of managing obesity do not even try. We hypothesized that practitioners' self-efficacy and motivation would be enhanced as a result of participating in an interactive course designed to enrich their knowledge of obesity management. 相似文献9.
10.
Transport of opioids from the brain to the periphery by P-glycoprotein: peripheral actions of central drugs 总被引:6,自引:0,他引:6
Many peptides and transmitters found within the brain also have peripheral sites of action. We now demonstrate that the brain releases functionally active neurotransmitters/neuromodulators directly from the brain into the blood through a saturable P-glycoprotein (Pgp) transport system. Downregulating Pgp1 expression with antisense reduced the brain-to-blood transport of morphine, beta-endorphin and other opioids. Lowering Pgp expression significantly enhanced systemic morphine analgesia and prevented tolerance, but diminished the analgesic activity of centrally administered morphine, implying that supraspinal analgesia resulted from a combination of central and peripheral mechanisms activated by morphine transported from the brain to the blood. Similarly, mice with a disruption of the Mdr1a gene were more sensitive to systemic morphine and less sensitive to morphine given centrally. This ability of the Pgp transport system to pump functionally active compounds from the brain to periphery defines a potentially important mechanism for the central nervous system to modulate peripheral systems. 相似文献