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91.
This study investigated the percentage of carbohydrate utilization than can be accounted for by glucose ingested during exercise performed after the ingestion of the potent lipolysis inhibitor Acipimox. Six healthy male volunteers exercised for 3 h on a treadmill at about 45% of their maximal oxygen uptake, 75 min after having ingested 250 mg of Acipimox. After 15-min adaptation to exercise, they ingested either glucose dissolved in water, 50 g at time 0 min and 25 g at time 60 and 120 min (glucose, G) or sweetened water (control, C). Naturally labelled [13C]glucose was used to follow the conversion of the ingested glucose to expired-air CO2. Acipimox inhibited lipolysis in a similar manner in both experimental conditions. This was reflected by an almost complete suppression of the exercise-induced increase in plasma free fatty acid and glycerol and by an almost constant rate of lipid oxidation. Total carbohydrate oxidation evaluated by indirect calorimetry, was similar in both experimental conditions [C, 182, (SEM 21); G, 194 (SEM 16) g · 3 h–1], as was lipid oxidation [C, 57 (SEM 6); G, 61 (SEM 3) g · 3 h–1]. Exogenous glucose oxidation during exercise G, calculated by the changes in13C:12C ratio of expired air CO2, averaged 66 (SEM 5) g · 3 h–1 (19% of the total energy requirement). Consequently, endogenous carbohydrate utilization was significantly smaller after glucose than after placebo ingestion: 128 (SEM 18) versus 182 (SEM 21) g · 3 h–1, respectively (P < 0.05). Symptoms of intense fatigue and leg cramps observed with intake of sweet placebo were absent with glucose ingestion.In conclusion, we found glucose ingestion during 3-h exercise with lipolysis blockade could provide metabolic substrate permitting a significant sparing of endogenous carbohydrate and consequently an improvement in performance.  相似文献   
92.
PurposeCartridge based nucleic acid amplification test (CBNAAT) has been endorsed by the WHO as the screening test for diagnosing extrapulmonary tuberculosis (EPTB). In the present study we report the agreement between CBNAAT (Xpert MTB/RIF), liquid culture (LC) and line probe assay (LPA) for diagnosis of Mycobacterium tuberculosis and detection of drug resistance among EPTB cases.MethodsThe EP samples were subjected to CBNAAT (Xpert MTB/RIF, Cepheid, USA) and wherever possible, to LC (MGIT 960, Becton Dickinson, USA) followed sequentially by first line and second line-LPA (FL-LPA, SL-LPA, Hain Lifescience, Germany) on the isolates.ResultsTotal 566/4080 (13.9%) EP samples were detected positive for M. tuberculosis on CBNAAT. Aspirates from lymph nodes were most often positive (11/30; 36.6%), followed by pus (240/873; 27.5%) and CSF samples (166/104; 15.8%). The detection of M. tuberculosis was more in adults than children except in tissue biopsy samples. Rifampicin resistance was also higher among adults except CSF in which resistance was more in children. Total 185 of 566 (32.7%) CBNAAT positive and 770 of 3510 (21.9%) CBNAAT negative samples could be cultured of which 110/185 (59.4%) and 33/770 (4.3%) respectively turned positive. FL-LPA and SL-LPA of 143 culture isolates showed that 27 isolates had drug resistance, of which 3 (2.1%) were XDR, 11 (7.7%) were Pre-XDR (FQ) and 13 (9.1%) were MDR. Of these 27 resistant isolates, 12 were negative by CBNAAT and two were mislabeled as Rifampicin sensitive or indeterminate based on the unique RpoB gene mutation patterns on LPA. The positive and negative agreements between LC and CBNAAT for detection of M. tuberculosis were 67.1% and 92.7% respectively and between LPA and CBNAAT for rifampicin resistance detection were 98.9% and 92.9% respectively.ConclusionsFor EPTB, CBNAAT should be accompanied with LC wherever possible irrespective of the CBNAAT result.  相似文献   
93.
Single neuronal activities were recorded in the oral region of the postcentral gyrus in conscious Japanese monkeys. Among 5,756 neurons isolated, receptive fields (RFs) and submodalities were identified in 1,502 neurons in area 3b, 970 in area 1, and 1,461 in area 2. The relative incidence of neurons that had bilateral RFs increased gradually upon moving caudally from area 3b to area 2 (bilateral integration). A total of 276 neurons had bimaxillary RFs covering both the maxillary and mandibular divisions of the trigeminal nerve, such as the upper and lower lips, upper and lower teeth, palate and tongue, or combinations thereof. There was also a tendency for the relative incidence of neurons with bimaxillary RFs to increase across the postcentral gyrus but with an abrupt change in area 2 (bimaxillary integration). A total of 382 neurons had composite RFs covering more than one of five oral structures: lip, cheek mucosa, teeth/gingiva, tongue, and palate. The relative incidence of neurons with composite RFs was significantly higher in area 2 than in areas 3b and 1 (interstructural integration). These results indicate that the convergence of inputs from oral structures proceeds in a hierarchical manner across the postcentral gyrus, but chiefly in area 2 for the bimaxillary and interstructural integrations. The relative incidence of neurons with composite RFs was higher among neurons associated with the teeth/gingiva or palate than among neurons associated with the tongue or lip in all three areas. We interpret this to mean that anatomical or functional differences between oral structures might be reflected in the converging patterns in the oral representation.  相似文献   
94.
Summary Porphyria cutanea tarda (PCT) was diagnosed in 27 women aged 23–48 years (mean, 35 years) who had been under oral-hormonal-contraceptive medication for 1–18 years, in 3 women under substitutional estrogen treatment in the menopause, and in 2 men aged 65 and 76 years after estrogen treatment of prostatic carcinoma. In all patients, total urinary porphyrin excretion was elevated, with an average uro-and heptacarboxyporphyrin predominance of 88%, thus proving PCT. On the patients, 84% showed a significant decrease of erythrocyte uroporphyrinogen-decarboxylase (UD; EC 4.1.1.37) activity to 50% of control levels suggesting a hereditary predisposition for the development of a chronic hepatic porphyria. Estrogens and alcohol are capable of reducing hepatic UD activity. Women with hereditary red cell UD deficiency may be regarded as predisposed to PCT when under estrogen intake, especially in combination with the potentiating influence of alcohol and chronic liver disease. Normal erythrocyte UD values in patients with additive alcohol consumption may implicate a stronger inhibitory effect for alcohol on UD, suggesting a merely toxic form of chronic hepatic porphyria.  相似文献   
95.
Summary The relationship between the concentrations of 5-hydroxyindoleacetic acid (5-HIAA) in the CSF and in the striatum has been evaluated in the rat by measuring the levels of this metabolite in ventricular CSF (by liquid chromatography coupled with electrochemical detection) and in the striatal extracellular fluid (byin vivo voltammetry) after administration of inhibitors of serotonin synthesis or degradation. Pargyline, NSD 1015 and-propyldopacetamide all caused an exponential decline of 5-HIAA in both CSF and striatum. For a given drug, the rate constants for 5-HIAA disappearance were identical in the CSF and in the striatal extracellular fluid. These results confirm the view that CSF 5-HIAA may serve as a good index of brain serotonin turnover.  相似文献   
96.
目的 建立超高效液相色谱-串联质谱法(UPLC-MS/MS)同时快速检测微量血清中维生素A、维生素D(25-OH-VD2 、25-OH-VD3 )、维生素E(α-、β-和γ-生育酚)的方法。方法 血清中脂溶性维生素经甲醇-乙腈(50:50, v/v)沉淀蛋白、正己烷萃取,以Phenomenex Kinetex F5色谱柱为分离柱,2.5 mmol/L甲酸铵-0.1%甲酸水溶液和甲醇为流动相,梯度洗脱,电喷雾电离(ESI+ )、多反应监测(MRM)模式下检测,同位素内标法定量。结果 血清中6种脂溶性维生素线性范围内线性关系良好,相关系数 r >0.995;6种脂溶性维生素的检测限为0.20~1.25 ng/ml,定量限为0.39~3.88 ng/ml;加标回收率为86.6%~107.7%,日内精密度<9.6%,日间精密度<9.3%。NIST标准参照品SRM 968f验证方法准确度,结果偏差均在5%以内。结论 本方法准确度高、重现性好、用血量少,适于婴幼儿等采血困难者微量血样中多种脂溶性维生素的同时快速检测。  相似文献   
97.
松针提取液对实验性高脂血症及脂质过氧化作用的影响   总被引:29,自引:0,他引:29  
经 8周高脂乳剂饲养后 ,选高脂血症造模成功的家兔 1 5只 ,随机分为对照组、松针提取液小剂量治疗组 (实验Ⅰ组 )、松针提取液大剂量治疗组 (实验Ⅱ组 )。取血测TG、TC、MDA含量和SOD活性及总抗氧化活力。结果动物经松针提取液治疗后 ,血TC及MDA含量降低 ,SOD活性及总抗氧化活力升高 ,与对照组比较 ,治疗Ⅱ组的降脂作用和抗氧化能力更显著。结论 :松针提取液对高脂血症有较强的降脂和抗氧化作用。  相似文献   
98.
目的:优选养血口服液提取工艺。方法:以干膏收率和总黄酮的含量为指标,采用正交试验法对养血口服液提取工艺进行研究。结果:确定最佳工艺条件为:水煎煮2次,第一次加10倍量水,煎煮1.5小时;第二次加8倍量水煎1,所得煎煮液浓缩至1ml,含1g生药,醇沉浓度为70%。结论:本法可用于养血口服液的生产。  相似文献   
99.
高效液相色谱法测定小儿热感宁口服液中葛根素含量   总被引:1,自引:0,他引:1  
目的:建立小儿热感宁口服液中葛根素的HPLC含量测定方法,方法:用Nova-pakC18柱,流动相为甲醇-水(25:75),在250nm波长处检测,结果:线性范围为10-100μg.ml^-1,葛根素的回收率为99.48%,RSD为1.38%(n=5)。结论。方法简便便速,精密度和稳定性良好,适合小儿热感宁口服液生产的质量控制。  相似文献   
100.
目的 优化柴银口服液提取工艺,明确其成品稳定性。方法 在单因素试验基础上将加水量、提取时间、提取次数作为考察因素,以黄芩苷转移率与澄清度值的总评归一(OD)值为评价指标,采用星点设计-效应面法优化柴银口服液提取工艺,将经优化后工艺条件生产的柴银口服液成品与原工艺成品进行加速与长期稳定性对比。结果 最佳提取工艺参数为加水量8.3倍、提取时间2.2 h、提取3次,此条件下OD值最高为0.702,此条件下生产的柴银口服液在稳定性考察中pH、澄清度、黄芩苷含量及微生物限度等指标均明显优于原工艺成品。结论 星点设计-效应面法优化柴银口服液提取工艺方法可靠、参数精确,能有效提升其价值、延长保质期。  相似文献   
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