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91.
Preliminary UK experience of dexmedetomidine, a novel agent for postoperative sedation in the intensive care unit 总被引:19,自引:0,他引:19
Venn RM Bradshaw CJ Spencer R Brealey D Caudwell E Naughton C Vedio A Singer M Feneck R Treacher D Willatts SM Grounds RM 《Anaesthesia》1999,54(12):1136-1142
Dexmedetomidine, a highly selective and potent alpha2-adrenergic agonist, has a potentially useful role as a sedative agent in patients requiring intensive care. As part of a larger European multicentre trial, a total of 119 postoperative cardiac and general surgical patients requiring ventilation and sedation in an intensive care unit were enrolled in four centres in the United Kingdom. One hundred and five patients were randomly allocated to receive either dexmedetomidine or placebo with rescue sedation and analgesia provided by midazolam and morphine, respectively. Compared with the control group, intubated patients receiving dexmedetomidine required 80% less midazolam [mean 4.9 (5.8) microg.kg-1.h-1 vs. 23.7 (27.5) microg.kg-1.h-1, p < 0.0001], and 50% less morphine [11.2 (13.4) microg.kg-1.h-1 vs. 21.5 (19.4) microg.kg-1.h-1,p = 0.0006]. Cardiovascular effects and adverse events could be predicted from the known properties of alpha-2 agonists. In conclusion, dexmedetomidine is a useful agent for the provision of postoperative analgesia and sedation. 相似文献
92.
以流行病学在病证结合的中医“证”研究中的应用为线索,光盘检索和手工查阅了1997—2002年的期刊文献,对若干疾病运用流行病学方法进行的大样本(100例以上)的中医证型临床研究结果作一个回顾和小结,从流行病学和统计学的角度分析科研和论文中存在的问题,提出改进方法和展望。 相似文献
93.
生化过程工程与中药现代化 总被引:6,自引:0,他引:6
在生化工程20余年的研究工作基础上。结合中药现代化开展了一些技术、材料与设备的研究开发工作。研究植物细胞、组织、器官大规模培养增殖技术,应用于细胞代谢产物、生物转化和人工育种及发根,实现了工厂化生产,并成功研制多种类型的生物反应器;在原有化学工程提取分离技术的基础上,发展了反应分离耦合、微波辅助提取等新技术,实现了高效浸出,并且节能、节水;此外,又发展了包括反胶团萃取、一步三相萃取青霉素、泡沫分级分离、膜分离、高速逆流色谱分离纯化等新技术。高速逆流色谱技术是一种没有固相载体的液一液多级逆流萃取技术,避免了不可逆吸附,已成功用于多种天然产物的分析和分离,作为研究中药指纹图谱的新方法具有很好的精密度和重现性。高效液相色谱、气相色谱、毛细管电泳、质谱等技术在指纹图谱研究中发挥了重要作用。与此同时,还研制了多种分离介质,并在药物的修饰与包埋方面做了大量工作。另外,在海洋药物研究领域,创造了连续培养连续采收的新流程、新技术.进行了转基因藻的培养。用于生产基因工程产品。 相似文献
94.
Objective: To observe the behavioral and biochemical effects of a traditional Chinese medicine Huanshao Dan (HSD) on learning and memory
deficits in transient cerebral ischemia model in mice.Methods: Step-through experiments, receptor binding test and choline acetyltransferase (ChAT) activities determination were performed.Results: Mice undertaken transient ischemia commited much more mistakes in step-through experiments and showed relatively higher3 H-MK801 binding in cerebral cortex and hippocampus than in sham operated animals. HSD decoction was most effective in reducing
these mistakes in mice. At the same time, and3 H-MK801 binding of cerebral cortex and hippocampus tissues were also significantly decreased, while ChAT activities in the
same tissues were increased.Conclusion: HSD might antagonize ischemic injury of brain through inhibition of glutamate N-methyl-D-Aspartic acid receptor overactivity.
ΔThis program was supported by National Nature Science Foundation of China (No.39421012) 相似文献
95.
Robert L. Harris MD Geoffrey W. Cundiff MD James P. Theofrastous MD Haewon Yoon MD Richard C. Bump MD W.Allen Addison MD 《American journal of obstetrics and gynecology》1997,177(6):1367-1371
OBJECTIVE: Our goal was to evaluate the role of intraoperative cystoscopy during surgery for pelvic organ prolapse and urinary incontinence. STUDY DESIGN: Charts of 224 consecutive patients who had intraoperative cystoscopy performed after urogynecologic surgery were reviewed. RESULTS: Nine injuries occurred that were unsuspected before cystoscopy, for an incidence of 4%. Six ureteral ligations occurred, four after Burch cystourethropexy and two after vaginal culdoplasty. Intravesical sutures were noted after two Burch procedures, and another injury occurred with passage of fascia lata through the bladder during a pubovaginal sling procedure. Eight injuries were managed by removal and replacement of the suture or sling with only one requiring ureteroneocystotomy. When patients with injuries were compared with those without, there were no statistical differences in demographic or surgical parameters. CONCLUSIONS: The potential for damage to the lower urinary tract is significant with complex urogynecologic surgery. Because of the increased and delayed morbidity associated with unrecognized injury, intraoperative surveillance cystoscopy should be considered a part of all such procedures.(Am J Obstet Gynecol 1997;177:71) 相似文献
96.
体外循环手术前后病人血清sIL-2R水平和T淋巴细胞亚群、NK细胞的变化及临床意义 总被引:4,自引:1,他引:4
目的:通过检测心脏体外循环(CPB)手术前后病人血清中可溶性白介素2-受体(sIL-2R)、T细胞亚群、自然杀伤细胞(NK),观察分析心脏CPB手术病人细胞免疫的影响及其临床意义。方法:选择24例风心病择期换瓣病人,术前、CPB10分钟、CPB2小时、术后第1天、3天、5天检测血清sIL-2R水平、T细胞亚群及NK细胞活性。术后第1天血清sIL-2R水平升高,CO4(辅助细胞)活性明显降低,CD4/CD8(辅助细胞/抑制细胞)比值下降,NK活性降低;并且sIL-2R与CD4、NK活性呈负相关。结论:低温心脏CPB手术对病人免疫机能有不良影响,临床应采取相应措施,改善术后病人的免疫机能。 相似文献
97.
Association of Loss of Heterozygosity at the p53 Locus with Chemoresistance in Osteosarcomas 总被引:4,自引:0,他引:4
Akiteru Goto Hiroaki Kanda Yuichi Ishikawa Seiichi Matsumoto Noriyoshi Kawaguchi Rikuo Machinami Yo Kato Tomoyuki Kitagawa 《Cancer science》1998,89(5):539-547
Although the osteosarcoma is considered to be among the most chemosensitive malignancies and preoperative chemotherapy is commonly applied, an appreciable proportion of cases are in fact quite insensitive. Predictive markers for chemosensitivity are therefore desirable in order to develop effective treatment strategies. Thirty-two cases of conventional osteosarcomas treated at the Cancer Institute Hospital, Tokyo, were analyzed. The sensitivity to preoperative chemotherapy was investigated with reference to loss of heterozygosity (LOH) at the 17p13 ( p 53) and 13q14 ( Rb ) loci and expression of the cell-cycle associated proteins, p53, Rb, p21/Waf-1, mdm-2 and Ki-67, as detected immunohistochemically. LOH was detected by analyzing polymerase chain reaction products at marker microsatellite loci. The efficacy of chemotherapy was evaluated both radiologically and histologically. LOH at p 53 or Rb loci was seen in 54% (13/24) and 58% (14/24) of cases, respectively. Only 15% of osteosarcomas with LOH at the p 53 locus were sensitive to preoperative chemotherapy, as compared to 64% of tumors without such loss ( P <0.05). A similar but much less distinct tendency was observed with LOH at the Rb locus. No relationship was evident between chemosensitivity and immunohistochemical staining patterns for p53, Rb, p21/Waf-1, mdm-2 or Ki-67. The results suggest that p 53 gene deletion, but not the other parameters investigated, may be useful for predicting chemoresistance of osteosarcomas. 相似文献
98.
Byung Mu Lee Ja-June Jang Joung-Soon Kim Young Chan You Sun Ah Chun Hyung Sik Kim Hyung Mee Han Mi Young Ahn Soo Hyun Byun 《Cancer science》1998,89(6):597-603
Gastric adenocarcinoma is the most prevalent cancer in South Korea, and Helicobacter pylori (H. pylori) infection is also common. This study was performed to examine the association between H. pylori infection and gastric cancer, taking into account various other factors. To investigate the association between gastric adenocarcinoma and H. pylori infection, determined by urease-positive reaction in the CLO test, a total of 175 paired specimens (175 tumor and 175 tissues adjacent to tumor) of stomach cancer patients and a total of 113 control specimens were obtained. The positive H. pylori infection rates were 78.9% (138/175) among the patients in specimens of tumor or tissues adjacent to the tumor and 41.6% (47/113) among controls in the CLO test. A positive correlation between H. pylori infection and gastric cancer was observed (age-adjusted odds ratio, 7.0; MH χ2 =34.5 with P <0.0005). These data suggest that stomach cancer patients in Korea have high infection rates of H. pylori regardless of site specificity, and this infection might be causally associated with stomach cancer. 相似文献
99.
Yoshinori Naoe Masamichi Inami Ikuo Kawamura Fusako Nishigaki Susumu Tsujimoto Sanae Matsumoto Toshitaka Manda Kyoichi Shimomura 《Cancer science》1998,89(6):666-672
FK317 is a member of a new class of bioreductive agents that exhibit strong cytotoxicity against various human cancer cells. The effect of FK317 was found to be stronger than that of mitomycin C (MMC), adriamycin (ADR) or cisplatin (CDDP). Alkaline elution analysis indicated that FK317 formed interstrand DNA-DNA and DNA-protein cross-links in cells. On the other hand, no DNA single-strand breaks were observed in the cells treated with FK317. In a cell-free system the deacetylated metabolites produced cross-linked DNA under reductive conditions, though FK317 itself did not form DNA-DNA cross-links. In order to elucidate the metabolic activation mechanisms, we established an FK317-resistant subline from human non-small cell lung cancer cells (Lu99) by stepwise and brief exposure (1 h) to FK317. The resistant subline (Lu99/317) showed cross-resistance to MMC and carboquone (CQ), but not to ADR or CDDP. DT-diaphorase, which is one of the activation enzymes of MMC and CQ, was deficient in Lu99/317 cells as determined by enzyme activity assay. However, the levels of NADPH:cytochrome P450 reductase, which is another activation enzyme for MMC and CQ, were comparable in resistant and parent cell lines. Treatment of the cells with dicumarol, an inhibitor of DT-diaphorase, reduced the cytotoxicity of FK317 to Lu99 cells, but not to Lu99/317 cells. These results indicate that deacetylation of FK317 is necessary for its reductive activation, and deacetylated FK317 is reduced by DT-diaphorase to form an active metabolite, which produces DNA-DNA interstrand and DNA-protein cross-links that lead to cell death. 相似文献
100.
Antitumor Immunity Induction by Intracellular Hyperthermia Using Magnetite Cationic Liposomes 总被引:10,自引:0,他引:10
Mitsugu Yanase Masashige Shinkai Hiroyuki Honda Toshihiko Wakabayashi Jun Yoshida Takeshi Kobayashi 《Cancer science》1998,89(7):775-782
Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8+ and CD4+ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced. 相似文献