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1.
Infections caused by extended-spectrum beta-lactamase (ESBL)-producing pathogens, particularly Klebsiella pneumoniae, are increasing. The epidemiology of ESBL-producing K. pneumoniae, the mechanisms of resistance, and treatment strategies for infections caused by these organisms are reviewed. 相似文献
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Marvin Rubenstein Robert Saffrin Michael Shaw Sergey Muchnik Patrick Guinan 《The Prostate》1995,27(3):148-153
Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc. 相似文献
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Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells. 相似文献
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表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
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We describe 3 patients with ureteral calculi who failed multiple extracorporeal shock wave lithotripsy treatments and whose stones could not be visualized by ureteroscopy despite radiological confirmation. We contend that these ureteral stones migrated submucosally and are refractory to the aforementioned treatment modalities. Each patient had a common presenting complaint of intermittent flank pain 5 years in duration, leading us to believe that long-standing stone impaction is a prerequisite for this entity. Our experience is reviewed. 相似文献
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PURPOSE: In children with intractable, surgically approachable epilepsy, the ketogenic diet is often perceived as less efficacious than surgery. METHODS: A retrospective chart review was performed of 554 children started on the ketogenic diet since 1994. Forty-five children were identified as surgical candidates, with at least 2 focal routine EEGs, ictal video-EEG, and corresponding focal neuroimaging findings, of whom 24 eventually had resective surgery and were followed subsequently. A comparison cohort group was also created of 45 children matched for age and seizure frequency that received the diet but were not surgical candidates (multifocal or generalized seizures). RESULTS: Of the 24 children who received both dietary and surgical therapies, there was a higher likelihood after 6 months of both >90% seizure reduction (71% versus 17%) and seizure freedom (63% versus 0%) following surgery, both p < 0.0001. Similarly, the 45 cohort children who were not surgical candidates were more likely to be seizure-free (29% versus 13%, p = 0.041) and remained on the diet for shorter duration (10 months versus 18 months, p = 0.035) compared to the surgical group. CONCLUSION: Children with surgically approachable epilepsy do respond to the diet, but are more likely to be seizure-free following surgery. 相似文献