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81.
(-)-Hydroxycitrate (HCA) is an active ingredient that is extracted from the rind of the Indian fruit, Garcinia cambogia, which is available as an herbal supplement and is used to lose weight. In this study, the acute and chronic effects of HCA on energy metabolism were examined in male Std ddY mice. Mice were placed into metabolic chambers and administered 10 mg HCA or water (control) orally. Serum free fatty acid levels were significantly higher 100 min after administration in the HCA group, but the respiratory exchange ratio was not different from that in the control group. The concentration of glycogen in the gastrocnemius muscle was higher in the HCA group 16 h after administration, and in a separate study, the maximum swimming time until fatigue was slightly longer (P: = 0. 21) than that in the control group on d 1. The difference was significant on d 3 after 3 d of HCA or water administration. Other mice were administered 10 mg HCA or water orally twice a day for 25 d. On d 26, they were placed into metabolic chambers after administration and allowed to rest for 1 h, followed by 1 h of running at 15 m/min. Respiratory gas was monitored. The respiratory exchange ratio was significantly lower in the HCA group during both resting and exercising conditions. These results suggest that chronic administration of HCA promotes lipid oxidation and spares carbohydrate utilization in mice at rest and during running.  相似文献   
82.
Dual therapy has been reported to produce H.pylori eradication rate of 75-80%. This study is designed to determine the efficacy of omeprazole 20 mg bd in combination with amoxycillin 500 mg tid (Group A), amoxycillin 750 mg tds (Group B) and clarithromycin 500 mg tid (Group C) in Singapore. One hundred and forty-eight patients with H. pylori positive duodenal ulcers between ages of 22 and 69 were enrolled from two centres. There were 48 patients in Group A, 50 patients in Group B and 50 patients in Group C. The medication was given for 14 days. The patients were re-evaluated with an upper GI endoscope 4 weeks after cessation of treatment Successful eradication was defined as H.pylori negative on histology and culture. Based on intention to treat analysis, the eradication rate was 47.8% in Group A, 68% in Group B and 66% in Group C. The difference between GroupA and B were statistically significant (p = 0.04). Based on all patient treated analysis, the eradication rate was 57.5% in Group A, 70.7% in Group B and 75% in Group C. The difference in eradication rates was not statistically significant. Adverse events were reported in 21% of all patients with no difference in the adverse event rate between all groups. The eradication rate achieved with dual therapy in this study was similar to that attained in Western population. Higher dose amoxycillin regime gives a significantly higher eradication than a lower dose amoxycillin.  相似文献   
83.
Giant cell arteritis is a chronic granulomatous inflammation of unknown aetiology involving large and medium size arteries in the elderly. It causes acute visual loss from ischaemia to the optic nerves or central retinal artery occlusion. This is a rare cause of anterior ischaemic optic neuropathy in our local population. We present a patient who had bilateral loss of vision from sequential arteritic ischaemic optic neuropathy. She was treated with intravenous steroids immediately. Diagnosis was based on histopathological studies of temporal artery biopsies.  相似文献   
84.
OBJECTIVES: To examine the variation in stated management of acute myocardial infarction (AMI) among clinicians of different specialties, and to compare stated with actual practice. DESIGN: Mail survey using a hypothetical case history, and review of medical records. SETTING: 47 public hospitals in New South Wales. SUBJECTS: 224 cardiologists, general/other physicians and general practitioners (GPs) who manage patients with AMI; 390 patients admitted for AMI between February and June 1996. OUTCOME MEASURES: Stated and actual use of treatments and investigations for AMI. RESULTS: Stated use of aspirin, thrombolysis and beta-blockers (95%-100%, 95%-100% and 80%-86%, respectively) was high in all three specialties. Cardiologists were significantly more likely than GPs to state use of heparin (87% v 57%; P < 0.001), ACE inhibitors (84% v 49%; P < 0.001) and echocardiography or gated pool heart scan (79% v 26%; P < 0.001). Stated use of nitrates by cardiologists was significantly lower compared with the other specialties (29% v 50% and 44%; P = 0.027). Actual use of aspirin was high (> 80%) in all specialties. Actual use of thrombolysis was similar to stated use after adjusting for factors such as time to hospital arrival and ST-segment elevation. There were substantial differences between stated and actual use. CONCLUSIONS: There were differences in practice patterns between and among clinicians of different specialties in NSW, consistent with findings from other countries. The high stated and actual use of aspirin and thrombolysis is encouraging.  相似文献   
85.
This study was carried out to investigate the modulation of detoxicant enzyme activity and plasma lipidemic levels by 150 kDa glycoprotein isolated from Solanum nigrum Linne (SNL), which has been used as a hepatoprotective and anticancer agent in folk medicine. Our results in this study showed that SNL glycoprotein has a band with 150 kDa on the 10% sodium dodecyl sulfate polyacrylamide gel, and that it has a strong scavenging activity against lipid peroxyl radicals. We also evaluated the lipidemic levels of SNL glycoprotein, based on lipoproteins and activities of detoxicant enzymes in treatment with Triton WR-1339 or corn oil in vivo. When mice were treated with either Triton WR-1339 or corn oil in the absence of SNL glycoprotein, the number of plasma lipoproteins [triglyceride (TG), total cholesterol (TC) and low density lipoprotein (LDL)] increased. However, when the mice were treated with either Triton WR-1339 or corn oil in the presence of SNL glycoprotein, the plasma lipoprotein levels (TG, TC and LDL) were significantly reduced. Similar results of SNL glycoprotein treatment were also produced in the activities of detoxicant enzymes. Namely, the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were remarkably increased after treatment with SNL glycoprotein. In addition, the activity of hepatic 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase was reduced by SNL glycoprotein in cholestyramine-treated mice. For example, we found that it inhibits the activity of cholestyramine-induced hepatic HMG-CoA reductase at 40 microg head body weight g(-1) SNL glycoprotein. Collectively, these results pointed out that SNL glycoprotein can enhance the activities of detoxicant enzymes and bring about the inhibition of HMG-CoA reductase activity in vivo. Therefore, we speculate that SNL glycoprotein can be used as a cholesterol-lowering agent even at low concentrations.  相似文献   
86.
The purpose of this study was to correlate the abnormal signal area on various magnetic resonance (MR) images to the infarct area on pathologic examination and to assess the myocardial viability on the basis of MR images. T2-weighted, first-pass perfusion, and delayed gadolinium-enhanced T1-weighted images were used as "one-stop examinations" in a pig model of reperfused myocardial infarction. The results of each MR image were compared with those of 2,3, 5-triphenyltetrazolium chloride (TTC) staining. The abnormal signal areas on T2-weighted and Gd-enhanced T1-weighted images were larger than the infarct areas on TTC staining (34.7% and 32.3% vs. 28.3%; P< 0.05), whereas the nonperfused areas on perfusion images were correlated (25.6% vs, 28.3%; P = 0.139). Electron microscopic examination showed severely distorted ultrastructures in the infarct areas and mildly damaged ultrastructures in the peri-infarct areas. Perfusion images probably reflected the infarct areas, whereas T2-weighted and Gd-enhanced T1-weighted images seemed to include peri-infarct as well as infarct areas.  相似文献   
87.
Ong EL  Lim NL  Koay CK 《Anaesthesia》2000,55(3):260-262
A randomised, prospective trial was conducted to assess the efficacy of various means of alleviating the pain of subcutaneous lidocaine infiltration. One hundred and twenty-two patients were randomly allocated to different groups to receive buffered lidocaine 1%, warmed lidocaine 1% or infiltration by the counter-irritation technique. A visual analogue pain score was recorded at different stages of cannulation and results showed that pain scores were significantly lower in the group receiving buffered lidocaine 1% (p < 0.02) and in the counter-irritation group (p < 0.05). Thus buffering lidocaine 1% and administration of lidocaine 1% by the counter-irritation technique is effective in relieving the pain of lidocaine infiltration.  相似文献   
88.
Anatomy of the iliolumbar ligament   总被引:3,自引:0,他引:3  
Information is lacking in the literature on the precise anatomy of the iliolumbar ligament and its individual differences. The morphologic pattern, length, and width of the iliolumbar ligament were determined in 56 embalmed lumbosacral spines from human cadavers. It was possible to classify the iliolumbar ligament into two groups: Type A (74 ligaments), in which anterior and posterior ligaments had separate courses; and Type B (32 ligaments), in which anterior and posterior ligaments moved together as one band. The angle of the posterior iliolumbar ligament in Type A was oriented significantly more posteriorly than that in Type B. The posterior iliolumbar ligament was significantly shorter and oriented more posteriorly in male anatomic specimens than in female ones.  相似文献   
89.
The auditory midbrain implant (AMI) is a new central auditory prosthesis designed for penetrating stimulation of the human inferior colliculus. The major group of candidates for the AMI consists of neurofibromatosis type 2 (NF2) patients who develop neural deafness because of growth and/or surgical removal of bilateral acoustic neuromas. Because of the absence of a viable auditory nerve, these patients cannot benefit from cochlear implants. An alternative solution has been the auditory brainstem implant (ABI), which stimulates the cochlear nucleus. However, speech perception performance in NF2 ABI patients has been limited. The fact that the ABI is able to produce high levels of speech perception in nontumor patients (with inaccessible cochleae or posttraumatic damage to the cochlear nerve) suggests that limitations in ABI performance in NF2 patients may be associated with cochlear nucleus damage caused by the tumors or the tumor removal process. Thus, stimulation of the auditory midbrain proximal to the damaged cochlear nucleus may be a better alternative for hearing restoration in NF2 patients. We propose the central nucleus of the inferior colliculus (ICC) as the potential site. A penetrating electrode array aligned along the well-defined tonotopic gradient of the ICC should selectively activate different frequency regions, which is an important elementfor supporting good speech understanding. The goal of this article is to present the ICC as an alternative site for an auditory implant for NF2 patients and to describe the design of the first human prototype AMI. Practical considerations for implementation of the AMI will also be discussed.  相似文献   
90.
BACKGROUND: Sevoflurane is metabolized by cytochrome P450 and produces inorganic fluoride. The anhepatic phase of liver transplantation provides a useful tool to study the extrahepatic metabolism of drugs. The authors therefore studied the extrahepatic metabolism of sevoflurane by measuring the fluoride production in children receiving sevoflurane solely during the anhepatic phase of orthotopic liver transplantation. METHODS: Children with end-stage liver disease undergoing orthotopic liver transplantation were studied. Anesthesia was provided with isoflurane, sufentanil, and pancuronium. In one group, isoflurane was replaced by sevoflurane as soon as the liver was removed from the patient and maintained until reperfusion of the new liver. Arterial blood samples were drawn at induction, before removal of the liver, 15 min and 30 min after the beginning of the anhepatic phase, at the unclamping of the new liver, and finally 60 and 120 min after the unclamping. Plasma fluoride concentrations were determined by ion-selective electrode. RESULTS: No differences between the two groups (n = 10) regarding age, weight, duration of the anhepatic phase, or basal level of inorganic fluoride were found. The fluoride concentration increased significantly as soon as sevoflurane was introduced; it remained stable in the group receiving isoflurane. The peak fluoride concentration was also significantly higher in the first group (mean +/- SD: 5.5 +/- 0.8 microM (sevoflurane group) versus 1.4 +/- 0.5 microM (isoflurane group) P < 0.05). CONCLUSIONS: These results demonstrate the existence of an extrahepatic metabolism of sevoflurane at least in children with end-stage liver disease.  相似文献   
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