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21.
Over the period 1986 to 1989, 53 cancer patients were identified with catheter-relatedStaphylococcus aureus bacteremia at the University of Texas M.D. Anderson Cancer Center. Septic thrombosis was diagnosed in 12 (23 %) patients and was suspected in another 3 (6 %). Of the 12 patients, five developed deep-seated infections (septic emboli, endocarditis, meningitis, abscess), compared with 2 of the 38 other patients with no septic thrombosis (p<0.01). Fever persisted for more than three days after antibiotic initiation in 52 % of the patients with complications (septic thrombosis and/or deep-seated infections), compared with 19 % of those without complications (p<0.02). Of the three patients with complications who were treated for 14 days with intravenous antistaphylococcal antibiotics, two relapsed; in contrast, all of the nine patients with complications who were treated for more than 14 days (mean 4 weeks) were cured, and none relapsed (p<0.05). Of the nine patients with complications who were treated with a long course of therapy, only one required surgery. The possibility of septic thrombosis and/or deep-seated infections should be considered in all cancer patients with catheter-relatedStaphylococcus aureus bacteremia, and if present, the condition should be treated with appropriate intravenous antibiotics for at least four weeks.  相似文献   
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Tiopinac displayed marked anti-inflammatory activity when given p.o. in rat models of acute and chronic inflammation. It inhibited carrageenan-induced paw edema (40 x phenylbutazone), and cotton-pellet-induced granuloma (0.8 x indomethacin). In an 18-day test, tiopinac prevented the development of adjuvant-induced arthritis (10–15 x naproxen) and had similar activity versus pre-induced arthritis. Tiopinac exhibited antiphlogistic activity in adrenalectomized rats. It did not have corticosteroid activity. Depending upon the type of analgesic test used, the potency of tiopinac varied. When given p.o. it inhibited henylquinone-induced writhing in the mouse and rat (respectively 16 and 10 x aspirin). In contrast, tiopinac had 10 times the potency of indomethacin in increasing the pain threshold when yeast-inflamed paws were compressed. The pain threshold of the noninflamed paw was not increased. Tiopinac was highly active versus pain induced by flexing the adjuvant arthritic-inflamed paw (1000 x aspirin). It was inactive in the mouse hotplate test in which opiate-like agents are active. Tiopinac, p.o., lowered yeast-induced pyrexia (130 x aspirin). Tiopinac did not have significant cardiovascular or CNS activity. Whereas the ED50 versus adjuvant arthritis in rats was 0.1 mg/kg/day p.o., rats tolerated up to 20 mg/kg/day p.o. in the 8-day cotton-pellet test. Lack of anorexia and emesis in dogs with up to 30 mg/kg p.o. and mild oral activity in producing gastric erosion in acute and subacute studies in rats suggests that tiopinac may have relatively little gastrointestinal irritating activity.A preliminary presentation of this study was delivered at the Federation of American Societies of Experimental Biology Meeting, Atlantic City, N.J., 1978 (Fed. Proc.37, 662 (1978).  相似文献   
23.
The main objective of this study was to examine the antimicrobial activity and durability of a novel indwelling bladder catheter impregnated with minocycline and rifampin. Thirty antimicrobial-impregnated bladder catheters were inserted transurethrally in spinal cord-injured patients and removed, in six groups of five catheters each, at 3, 7, 10, 14, 17 or 21 days. Removed catheters had detectable zones of inhibition against two different clinical isolates of each of the 10 tested uropathogens (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter diversus, Enterococcus faecalis, Enterococcus faecium, Staphylococcus saprophyticus and Candida albicans) for greater than 14 days after catheter insertion. The residual zones of inhibition and levels of antimicrobial agents in removed catheters were both inversely related to the duration of catheter placement. Minocycline and rifampin were undetectable in serum and urine. These results support the ongoing efforts for examining the clinical efficacy of these experimental bladder catheters.  相似文献   
24.
The antimicrobial susceptibility to ten antibiotics of 197 staphylococcal isolates recovered over a 10-year period from patients with vascular catheter-related bacteremia was examined. Isolated organisms induced methicillin-sensitive Staphylococcus aureus (95 isolates), methicillin-resistant S. aureus (42 isolates) and methicillin-resistant S. epidermidis (60 isolates). A microtiter assay was used to determine the MIC and MBC of individual antibiotics and to conduct time-kill studies of certain drug combinations. The activity of clidamycin, cefamandole and oxacillin was generally restricted to methicillin-sensitive organisms, whereas daptomycin, novobiocin, teicoplanin and vancomycin exhibited bactericidal activity against all tested staphylococcal species. Bacterial resistance to ciprofloxacin was detected among the more recent isolates of methicillin-resistant staphylococci. Minocycline and rifampin demonstrated bacteriostatic and bactericidal activity, respectively, against all groups of organisms. The interaction of rifampin with minocycline, vancomycin, or novobiocin was generally indifferent. The results of this study support the ongoing efforts for evaluation of the antimicrobial efficacy of vascular catheters coated with the combination of minocycline and rifampin.  相似文献   
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Sevoflurane was compared to isoflurane anesthesia alone and in combination with atracurium or vecuronium in 84 rats using the sciatic nerve—anterior tibialis muscle preparation. Both bolus injection and infusion rate techniques were used to evaluate these drug interactions. The ED50 (dose which produced a 50% depression of twitch tension) of atracurium was 311 ± 31 and 360 ± 32µg·kg–1 during 1.25MAC sevoflurane and isoflurane anesthesia respectively. The ED50 of vecuronium was 190 ± 27 and 149 ± 14µg·kg–1 during 1.25MAC sevoflurane and isoflurane anesthesia respectively. The mean infusion rates of atracurium and vecuronium required to maintain a 50% depression of twitch tension were 5.04 ± 0.7 and 2.02 ± 0.3mg·kg–1·hr–1. These infusion rates were 5.04 ± 0.7 and 2.02 ± 0.3mg·kg–1·hr–1 during 1.25MAC sevoflurane and 3.73 ± 0.3 and 1.81 ± 0.4mg·kg–1·hr–1 during 1.25MAC isoflurane anesthesia respectively. With both atracurium and vecuronium, the infusion rate required to maintain a 50% depression twitch of tension was inversely related to the concentrations of isoflurane and sevoflurane. The authors conclude that sevoflurane is similar in potency to that of isoflurane in augmenting a vecuronium or atracurium induced neuromuscular blockade in a dose-dependent manner.(Shin YS, Miller RD, Caldwell JE, et al.: The neuromuscular effects of sevoflurane and isoflurane alone and in combination with vecuronium or atracurium in the rat. J Anesth 6: 1–8, 1992)  相似文献   
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The study describes practices relating to syringe acquisition and disposal by Syringe Exchange Programme (SEP) participants. A cross-sectional multi-city study enrolled 857 injection drug users (IDUs) from six SEPs in different Brazilian regions, and assessed self-reported acquisition and disposal behaviours. Seven hundred and nine males (82.9%) and 146 females (17.1%) were recruited through outreach and interviewed, most from the streets or their neighbourhoods (54.1%). The average age was 28.5 years; 76.4% reported injecting cocaine in the past 6 months. Sources for acquiring new syringes differed significantly between time of injection drug use debut and the 6 months prior to interview. Fifty-three percent of IDUs reported acquiring their syringes in pharmacies when they initiated injection drug use, whereas most reported acquiring new syringes in the 6 months before interview from several simultaneous sources: 69% through SEPs; 58% through pharmacies; 36% from friends and/or sexual partners; and 17% from other health services. Across SEPs, acquisition and disposal varied widely. Most interviewees discarded their syringes on the streets, in open fields, or in the garbage or sewage. Restrictions on syringe availability and unsafe practices may be functioning as barriers to the public health recommendation of one-time use of sterile syringes for IDUs and discouraging community support to SEPs. Further increase in access to legal, inexpensive and timely sterile syringes, as well as counselling about the merits of one-time use and safer disposal must be reinforced as part of efforts to minimise high-risk behaviours and curb the spread of blood-borne infections.  相似文献   
30.
目的:建立蒺藜中蒺藜新苷的含量测定方法。方法:应用高效液相色谱法-蒸发光散射检测器,Supelco C18色谱柱(250mm×4.6mm,10μm),乙腈-甲醇-水(30:10:60)为流动相,流速为1.0 mL·min-1,Sedex蒸发光散射检测器参数:漂移管温度41℃,压力2.2×105 Pa。测定了蒺藜中蒺藜新苷的含量。结果:蒺藜新苷在3.988-13.96μg范围内有良好线性关系,r=0.9995(n=6)。蒺藜新苷的平均回收率为97.5%(n=6)。结论:该方法快速简便,灵敏、准确,可用于蒺藜药材中蒺藜新苷的含量测定。  相似文献   
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