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BACKGROUND: Allergen extracts are unstable, heat labile or susceptible to proteases. Stability of allergen extracts is important for proper diagnosis and therapy of allergic disorders. OBJECTIVE: The present study was undertaken to determine the preservation and stabilization conditions of Imperata cylindrica (Ic) grass pollen extract. METHODS: The Ic extract was kept with 0.1 mepsilon-aminocaproic acid (EACA), 0.75 m sucrose, 5% glycerol, 0.03% human serum albumin (HSA) or 0.4% phenol for different time periods. The extracts were stored for 3, 6 and 12 months each at 4 degrees C, 4 degrees C with daily exposure to room temperature (RT) for 1 h, and RT. The quality of extracts was analysed by SDS-PAGE, Western blot, ELISA, ELISA inhibition and skin test. RESULTS: Extracts kept with EACA and sucrose retained most of the protein bands followed by glycerol as determined by SDS-PAGE and Western blot during all storage periods and conditions in comparison with standard extracts. The extracts kept with HSA, phenol and without preservative (WP) showed protein degradation below 33 kDa after 3 months storage at all conditions. However, a 67-kDa allergen was stable in these extracts. EACA extract required 75 to 120 ng of protein for 50% inhibition in IgE binding under different conditions, whereas standard extract required 70 ng for the same. ELISA also demonstrated high allergenic reactivity of EACA extract. ID test on allergy patients with EACA extract demonstrated same allergenic potency as that of standard extract. CONCLUSION: EACA is the best preservative/stabilizing agent of Ic pollen extract, followed by sucrose and glycerol. Ic extract kept with phenol, HSA and without preservative showed degradation within 3 months. EACA preserved extract is equally potent as that of standard extract up to 1 year's storage.  相似文献   
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In the present study 60 diabetics were examined for intraocular pressure, scleral rigidity and facility of outflow. The intraocular pressure was found higher than in the general population except in patients with proliferative retinopathy. There was no marked difference in scleral rigidity in diabetics. The facility of outflow was lower in diabetic patients.  相似文献   
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The long term performance of various pacing leads in use for at least one year is reported from one centre. Between January 1975 and December 1990, 1056 cardiac pacing leads were implanted in 881 patients (mean age 57 +/- 13 years). Eight hundred and three leads were silicone insulated (SI) and 253 leads were polyurethane insulated (PUI). Leads from different manufacturers were used (Medtronic, CPI, Telectronics). The average duration of follow up was 56.6 +/- 77 months (range 12-221 months) for SI and 47.1 +/- 24 months (range 12-99 months) for PUI leads. Overall lead failure occurred more often in the PUI group (n = 46, 18.2%) compared to SI group (n = 93, 11.3%, p < 0.025). Majority of lead failures occurred in the first 36 months after implantation. In particular, Medtronic models 6971, 6972 (urethane) and 6901 (silicone) showed higher rate of complications (25.5%, 26.3% and 44.5% respectively).  相似文献   
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Effect of imipramine treatment on heart rate variability measures.   总被引:1,自引:0,他引:1  
Recently, heart rate (HR) variability has received considerable attention, and a decreased HR variability has been linked to a significant risk of cardiovascular illness. We have previously reported such a decreased variability in panic disorder patients. In this study, we report on HR variability in 12 depressed and 6 panic disorder patients at baseline and 1 and 3 weeks of treatment with imipramine as measured by the standard deviation, mean consecutive difference and the standard deviation of the mean consecutive difference of the R-R intervals in supine, supine deep breathing and standing postures. In all subjects, imipramine (mean dose: 70 mg/day) produced a significant decrease in heart rate variability at week 3 as measured by the above variables. This decrease in HR variability during imipramine treatment is probably due to its anticholinergic effects.  相似文献   
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Surgery in tropical pancreatitis: analysis of risk factors.   总被引:2,自引:0,他引:2  
Over a 7-year period, 91 patients with tropical pancreatitis underwent operation for intractable pain. Univariate and multivariate analyses were performed to identify factors correlating with mortality, major complications, poor pain relief and associated malignancy. Patients with benign disease (group 1, n = 72) had longer survival than those with superimposed malignancy (group 2, n = 19). Pain relief was better in group 1 (59 patients compared with none, P less than 0.01). Age above 40 years, short duration of symptoms, mass lesions on ultrasonography and main pancreatic duct obstruction on endoscopic retrograde pancreatography were associated with a high risk of cancer. After reoperation major complications (four of ten) or death (three of ten) occurred more commonly than after primary procedures (seven of 81, P = 0.019 and five of 81, P less than 0.05, respectively). Poor pain relief in group 1 patients was more common after incomplete clearance of main duct stones (four of 13 versus three of 53, P less than 0.01) and after short length ductotomy (three of eight versus four of 58, P less than 0.01). Tropical pancreatitis has a high association with pancreatic adenocarcinoma. Wide ductotomy, stone clearance and drainage gave good symptomatic results in patients with benign disease. Overall results were poor in patients with cancer.  相似文献   
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目的:前瞻性研究青光眼术中应用丝裂霉素C(MMC)对于结膜滤过泡高危因素如无血管化、经结膜的渗漏(TCO)和滤过泡裂孔的影响。方法:一位观察者对进行了青光眼手术联合MMC的125例连续患者的125只眼进行为期2年的前瞻性研究,这些患者最初都成功地建立了滤过通道。巩膜瓣切开前将MMC置于该区,多数患者MMC0.2g/L持续2min。青光眼手术包括小梁切除术、深巩膜切除术和联合手术。将干燥的荧光素试纸置于滤过泡的无血管区,以观察房水外流[点渗漏(PL)或未流出(TCO)]。  相似文献   
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OBJECTIVE: To compare the effects of Humalog Mix25 (Humalog Mix75/25 in the USA) (Mix25) and human insulin 30/70 (30/70) on the 24-hour inpatient plasma glucose (PG) profile in patients with type 2 diabetes mellitus (T2DM). DESIGN: A randomised, open-label, 8-week crossover study. Study insulins were injected twice daily, 5 minutes before breakfast and dinner. SETTING: Four-week outpatient (dose-adjustment) treatment phase, and 3-day inpatient (test) phase. PATIENTS: Twenty-five insulin-treated patients with T2DM (ages 40-66 years), mean (+/- standard error of the mean) (SEM) HbA1c 7.7% +/- 0.23%, and body mass index (BMI) 29.3 +/- 0.83 kg/m2. OUTCOME MEASURES: 24-hour PG profiles, PG excursions after meals, PG area under the curve (AUC), and 30-day hypoglycaemia rate. RESULTS: The 2-hour PG excursions following breakfast (5.5 +/- 0.34 v. 7.2 +/- 0.34 mmol/l, p = 0.002) and dinner (2.4 +/- 0.27 v. 3.4 +/- 0.27 mmol/l, p = 0.018) were smaller with Mix25 than with 30/70. PG AUC between breakfast and lunch was smaller with Mix25 than with 30/70 (77.6 +/- 3.8 v. 89.5 +/- 4.3 mmol/h/ml, p = 0.001). PG AUC between lunch and dinner, dinner and bedtime, and bedtime and breakfast did not differ between treatments. Pre-meal and nocturnal PG were comparable. The postprandial insulin requirement for lunch meals was supplied equally by the two insulin treatments. The thirty-day hypoglycaemia rate was low (Mix25 0.049 +/- 0.018 v. 30/70 0.100 +/- 0.018 episodes/patient/30 days, p = 0.586) for both treatments. CONCLUSION: In patients with T2DM, Mix25 improved the 24-hour PG profile with lower postprandial PG excursions than with human insulin 30/70.  相似文献   
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