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21.
The dermal absorption of niclosamide, a drug shown to prevent Schistosomiasis by blocking the dermal penetration of cercariae, has been examined in Sinclair minipigs and rats. Radioactivity in the urine and feces collected daily for 7 days after application of 14C-niclosamide accounted for less than 2 per cent and 10 per cent of the labelled compound applied to pig and rat skin, respectively. Approximately 20 per cent of the radioactivity from the dose solution was recovered on the skin excised from the area of application in both minipigs and rats. No radioactivity was detected in organs removed from the pig 7 days after application of radiolabelled drug while less than 6 per cent of the dose could be accounted for in the rat organs/carcass. Radioactivity in swine blood, removed 0.5, 1, 2, 4 and at 24 h intervals after dosing, was at or below three times background in all of the samples. Total recovery of the applied radioactivity was 78 per cent in pigs and 57 per cent in rats. These studies indicate that niclosamide is very poorly absorbed after dermal application. The results are consistent with earlier comparative studies showing that dermal penetration of xenobiotics in rats is generally higher than in swine.  相似文献   
22.
With the increased use of indwelling central venous catheters, increasing numbers of cases of Rhodotorula fungemia have been observed in patients with neoplasia and neutropenia. In most patients with catheter-related Rhodotorula fungemia, the condition has been treated with broadspectrum antibiotics. We report two cases of central venous catheter-related Rhodotorula rubra fungemia that occurred in patients with acute myeloblastic leukemia. Both patients were in a state of neutropenia. One patient was treated with amphotericin B and his central venous catheter was removed, but he died of Klebsiella pneumoniae bacteremia. The other patient was treated with amphotericin B and discharged, with a central venous catheter, after recovery from neutropenia. Although the management of catheter-related Rhodotorula fungemia infections remains controversial, resolution of the underlying disease is more important than catheter removal for recovery from Rhodotorula rubra fungemia. Received: August 22, 2001 / Accepted: October 8, 2001  相似文献   
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BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.  相似文献   
27.
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished.  相似文献   
28.
Background: The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods: The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mm K+ Tyrode solution with 0.1 [mu]m isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca2+ release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na+ Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca2+ and K+ currents of guinea pig ventricular myocytes were examined.

Results: Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mm K+ Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na+ Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca2+ current and the delayed outward K+ current but did not alter the inward rectifier K+ current.  相似文献   

29.
Pain management in ambulatory surgery.   总被引:1,自引:0,他引:1  
Successful ambulatory surgery is dependent on analgesia that is effective, has minimal adverse effects, and can be safely managed by the patient at home after discharge. A number of studies have identified that the provision of effective postoperative analgesia is inadequate for a significant proportion of patients. The following discussion details the current available analgesic options for ambulatory surgery patients and the rationale for their use. Preemptive analgesia should be given to all patients unless there are specific contraindications. Consideration should be given to the use of long-acting oral COX-2 selective nonsteroidal anti-inflammatory drugs (NSAIDs) and long-acting oral opioids to treat postoperative pain. A standardized multimodal postdischarge analgesic regimen tailored to the patient's expected postoperative pain levels should be prescribed. Patient follow-up by telephone questionnaire will confirm those surgical procedures that result in mild or moderate-to-severe postoperative pain and the effectiveness of treatment plans.  相似文献   
30.
Mammalian bones have three distinct origins (paraxial mesoderm, lateral plate mesoderm, and neural crest) and undergo two different modes of formation (intra-membranous and endochondral). Bones derived from the paraxial mesoderm and lateral plate mesoderm mainly form through the endochondral process. During this process, hypertrophic chondrocytes play a vital role in inducing both osteogenesis and angiogenesis. One of the essential osteogenic factors secreted from hypertrophic chondrocytes is Indian hedgehog (Ihh). In contrast, bones derived from the neural crest mainly form through the intramembranous pro-cess and do not require Ihh. Thus, depending on their origin, bones have distinct signaling properties, which need to be considered in the research and application of bone biology.Presented at the 18th Annual Research Meeting of the Japanese Orthopaedic Association, Kitakyushu, Japan, October 17, 2003  相似文献   
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