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PURPOSE: The combination of antiemetic drugs could be a solution to prevent severe postoperative nausea and vomiting (PONV). The aim of this randomized double blind, dose-ranging study was to determine the minimum single effective dose of dexamethasone combined with ondansetron for the prevention of PONV in patients undergoing laparoscopic cholecystectomy. METHODS: One hundred eighty patients were allocated randomly to one of six groups to receive saline (P group), ondansetron 4 mg (O group), or ondansetron 4 mg and dexamethasone at doses of 2 mg (OD2 group), 4 mg (OD4 group), 8 mg (OD8 group), and 16 mg (OD16 group). A standardized general anesthetic was used. All episodes of PONV during the intervals of zero to six hours, 6-12 hr and 12-24 hr after surgery were evaluated using a numeric scoring system. Mean visual analogue scale pain scores at rest and on movement, the time to first demand of analgesia, total analgesic consumption in 12 hr epochs, duration of hospital stay, and side effects were recorded. RESULTS: The incidence of PONV in the OD8 (16%) and OD16 (16%) groups was lower than in the 83% (P < 0.001) and O groups (50%) at the 12-24 hr epoch (P < 0.05). There were no differences in antiemetic effect between the O, OD2 and OD4 groups and between the OD8 and OD16 groups. Pain scores, total analgesic consumption, duration of hospital stay and side effects were similar among groups. CONCLUSION: Our results suggest that 8 mg is the minimum dose of dexamethasone that, combined with ondansetron 4 mg will effectively prevent PONV in patients undergoing laparoscopic cholecystectomy.  相似文献   
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A 5-year-old girl presented with a 1-year history of a subcutaneous swelling in the right parietal region. There were no cerebral symptoms or signs. Plain X-ray of the skull showed a lytic bony lesion with sclerotic margin. Computed tomography showed a hypodense, osteolytic lesion with thinned and bulged inner and outer skull tables with intact continuity. There was no intracranial lesion. At operation, the mass was found to be pink and granular, and was totally enucleated. Histology revealed it to be a benign osteoblastoma.  相似文献   
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This work describes the synthesis of new amphiphilic perfluorohexyl- and perfluorooctyl-propanethio-beta-cyclodextrins and the comparison of the ability of these molecules and alkyl analogue, nonanethio-beta-cyclodextrin to form nanospheres. Nanospheres were prepared using nanoprecipitation method (perfluoroalkylthio-beta-cyclodextrin in THF [0.11 x 10(-3)M], stirring rate 700rpm, addition of aqueous phase at 64 degrees C into organic phase at 50 degrees C). They were characterised by Photon Correlation Spectroscopy (PCS) and by electron microscopy (SEM and cryo-TEM). The nanospheres prepared from these new beta-cyclodextrin derivatives have an average size of 260nm, and appear to be spherical in cryo-TEM images. Whereas alkyl analogue forms polydisperse aggregates with sizes in the range 60-350nm.  相似文献   
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Reference values for 75 g oral glucose tolerance test in pregnancy   总被引:1,自引:0,他引:1  
A 75 g oral glucose tolerance test was performed in 212 pregnant women with no predisposing factors suggesting glucose intolerance to establish the normal pattern of glucose metabolism in pregnancy. Reference values for the test were established for the middle of pregnancy (14-20 weeks, n = 43) and late pregnancy (28-37 weeks, n = 168). One woman was excluded because she had diabetes that required treatment with insulin. There were statistically significant differences between the two groups for samples taken both one and two hours after the glucose load. Reference ranges for the interpretation of the glucose tolerance test in pregnancy should therefore take account of the period of gestation. Arbitrary upper limits of normal (represented by the 97.5 centile) two hours after a 75 g oral glucose load are proposed at 7.5 and 9.6 mmol/l for the second and third trimesters, respectively.  相似文献   
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OBJECTIVE: In a prospective study, the effect of thymectomy on the pulmonary status of 50 consecutive patients with myasthenia gravis was evaluated over a time range of 4 years in the Chest and Chest surgery departments in the Cairo University Clinics and Thoracic Surgery Department of the Evangelisches Krankenhaus Duisburg-Nord. METHODS: The patients were divided into two groups: Group I included 26 patients who underwent thymectomy through median sternotomy. The mean age of the patients in this group was 24.8+/-10.5 (5-41) years. They were 19 females and seven males. Thirteen of the patients were in Myasthenia Gravis Foundation of America (MGFA) class IIa, and 12 were in class IIb, and one was in class IIIa. Group II included 24 patients who underwent thymectomy through manubriotomy. The mean age of the patients in this group was 25.2+/-9.2 (12-41) years. They were 13 females and 11 males. Eight of the patients were in MGFA class 2a, 14 were in class IIb, and two were in class IIIa. RESULTS: When compared to group I in which postoperative ventilation was required in 15.4% of patients, postoperative ventilation was not necessary in patients of group II with a statistically significant difference (P=0.04). The mean duration of stay in the intensive care unit was 111.4h in group II, and 169.7h in group I (P=0.03). The peak inspiratory flow rate and the forced vital capacity were also statistically significantly better in group II. There was no mortality in both groups, and the morbidity was higher in the median sternotomy group. CONCLUSION: Thymectomy through a manubriotomy, which allows extensive removal of ectopic thymic tissue in addition to the thymus through a less invasive approach than a full median sternotomy, is associated with a significantly smoother postoperative course and less pulmonary complications, when compared with thymectomy through a full median sternotomy.  相似文献   
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Anaerobic infections of the urinary tract: are they being missed?   总被引:2,自引:1,他引:1       下载免费PDF全文
Routine anaerobic culture of urine identified the urinary tract as the primary focus of sepsis in a postoperative patient with Bacteroides fragilis septicaemia. Specimens of urine from six other symptomatic patients grew > 10(8) cfu/litre of a Bacteroides species in pure growth. The significance of these isolates is discussed. Multipoint technology and the availability of anaerobic work stations have facilitated anaerobic culture and reduced its cost. The incorporation of anaerobic culture of urine into routine laboratory practice may be clinically valuable and should be considered.  相似文献   
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The rabbit model of tuberculosis has been used historically to differentiate between Mycobacterium tuberculosis and Mycobacterium bovis based on their relative virulence in this animal host. M. tuberculosis infection in market rabbits is cleared over time, whereas infection with M. bovis results in chronic, progressive, cavitary disease leading to death. Because of the innate resistance of commercial rabbits to M. tuberculosis, 320 to 1,890 log-phase, actively growing inhaled bacilli were required to form one grossly visible pulmonary tubercle at 5 weeks. The range of inhaled doses required to make one tubercle allows us to determine the relative pathogenicities of different strains. Fewer inhaled organisms of the M. tuberculosis Erdman strain were required than of M. tuberculosis H37Rv to produce a visible lesion at 5 weeks. Furthermore, with the Erdman strain, only 7 of 15 rabbits had healed lesions at 16 to 18 weeks; among the other animals, two had chronic, progressive cavitary disease, a phenotype usually seen only with M. bovis infection. Genotypic investigation of the Erdman strain with an H37Rv-based microarray identified gene differences in the RD6 region. Southern blot and PCR structural genetic analysis showed significant differences between M. tuberculosis strains in this region. Correlation of the relative pathogenicity, including disease severity, in the rabbit model with the strain genotype may help identify stage-specific M. tuberculosis genes important in human disease.  相似文献   
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