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黑柴胡中新三萜皂甙的结构鉴定   总被引:3,自引:0,他引:3  
从黑柴胡(Bupleurum smithii Wolff)根中分离出10个化合物,均为首次由该植物中获得。其中二个新三萜皂甙,即柴胡皂甙k和l(saikosaponin k and l),其结构经紫外、红外、核磁共振氢谱,碳谱和质谱等波谱测定和解析,分别确定为3β,16β,23,28-四羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃木糖基-(1→2)-β-D-吡喃葡萄糖基-(1→3)-β-D-吡喃呋糖甙和3β,16α,23,28,30-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基-(1→3)-β-D-吡喃呋糖甙。  相似文献   
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The serum lipid and lipoprotein levels of 59 obese Chinese children with a mean age of 13.0 years and mean relative weight of 164.2% were analysed. Between 40% to 54% of these children had elevated lipid and lipoprotein levels and about 78% had reduced high density lipoprotein (HDL) level when compared to healthy American and Japanese children. The obese children also had higher mean levels of total cholesterol (TC) and lower HDL compared to male adults in the local population. Those with elevated TC had higher mean relative weight (170% vs 159%, p < 0.05). In view of the close association between hyperlipidaemia and atherosclerosis, obese children should be carefully screened and managed to prevent long term morbidity and mortality of coronary artery disease.  相似文献   
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We report a case of an 80-year-old man with osteoblastic metastases from advanced carcinoma of the prostate presenting with a grand mal seizure resulting from severe hypocalcaemia. He had low serum phosphate and ionised calcium levels, elevated serum skeletal alkaline phosphatase and intact parathormone levels. 99mTc radioisotope bone scan revealed a "super bone scan" suggestive of osteomalacia. The serum 1, 25-dihydroxycholecalciferol level was unexpectedly elevated. The biochemical abnormalities persisted despite high dose calcium replacement, but improved with supraphysiological doses of 1,25 (OH)2 vitamin D3 (Rocaltrol) therapy. We hypothesise that the hypocalcaemia in this patient was due to vitamin D resistance secondary to a humoral factor secreted by the tumour.  相似文献   
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Transabdominal duplex Doppler ultrasonography (TDDU) is commonly used for measuring hepatic blood flow (HBF) in clinical practice. Flow velocity and the cross-sectional area (CSA) of vessels are obtained separately and used to compute blood flow. Respiration and changes in portal pressure are known to cause variations in the CSA of the portal vein, but the impact of these parameters on TDDU measurement of portal blood flow is unclear. Eight Yorkshire pigs (20.7-25.1 kg) were used for the study. TDDU determination of portal blood flow was carried out using CSA of the portal vein obtained at inspiration (maximal) and at expiration (minimal) for computation, and the differences obtained were compared. Determination of HBF was carried out simultaneously on the same animals using diisopropyliminodiacetic acid (DISIDA) clearance. A physiological increase in portal pressure was then created by 50% hepatectomy and TDDU measurement similarly carried out on the second postoperative day. Computing portal blood flow in the intact liver using maximal and minimal CSA gave rise to a mean difference of 7.0 ml kg(-1) min(-1) (P < 0.001). A significant correlation was obtained between HBF and portal flow computed from maximal CSA (Pearson's correlation = 0.85, P < 0.033). The respiratory index of the portal vein (maximal CSA/minimal CSA) decreased from 1.5 to 1.2 after hepatectomy, which also caused a 90% increase in portal pressure. Respiration and portal pressure thus significantly impact on TDDU determination of HBF, and in this porcine model, computation using maximal CS more accurately reflects HBF.  相似文献   
7.
The effects of galvanic stimulation on the human vestibulo-ocular reflex   总被引:2,自引:0,他引:2  
We studied the effects of 5 mA bilateral or unilateral, bipolar or monopolar, galvanic stimulation on the horizontal vestibulo-ocular reflex (hVOR) in six normal subjects during 0.01, 0.05, 0.1, 0.5 and 1 Hz yaw rotations and in two subjects during high-acceleration, low-amplitude yaw head rotations (head impulses). Bipolar galvanic stimulation induced horizontal nystagmus in all subjects and an asymmetry of the hVOR only during rotations below 0.1 Hz. Monopolar stimulation had no significant effect. The findings suggest that in humans galvanic stimulation affects those primary horizontal semicircular canal neurons that mediate the hVOR via indirect pathways through the velocity storage mechanism.  相似文献   
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The 52‐week results from the CLEAR (NCT02074982) study showed high and superior efficacy of secukinumab versus ustekinumab in clearing skin and improving patient‐reported outcomes, with comparable safety profile in subjects with moderate to severe psoriasis. Here, we analyzed the efficacy and safety of secukinumab in Asian subjects from the CLEAR study. In this double‐blind, phase IIIb study, eligible subjects with moderate to severe plaque psoriasis were randomized (1:1) to receive s.c. injection of secukinumab 300 mg or ustekinumab as per label. Of 62 subjects included in Asian subanalyses, 23 were randomized to secukinumab and 39 to ustekinumab. A significantly higher proportion of subjects achieved 90% or more improvement in Psoriasis Area and Severity Index (PASI 90) with secukinumab versus ustekinumab at week 16 (78.3% vs 35.9%, = 0.0010) and at week 52 (60.9% vs 33.3%, = 0.0196). Similarly, a higher proportion of subjects achieved PASI 100 with secukinumab versus ustekinumab at week 16 (43.5% vs 10.3%, = 0.0029) and at week 52 (30.4% vs 12.8%, = 0.0704). The median time to achieve 50% improvement in baseline PASI was 2.8 weeks in the secukinumab group versus 6.3 weeks in the ustekinumab group. The safety profile of secukinumab was in line with the known profile and no deaths occurred. Overall, 95.7% and 84.6% of subjects remained on secukinumab and ustekinumab, respectively. Similar to the core study, secukinumab showed sustained and superior efficacy with faster response versus ustekinumab, and no new or unexpected safety concerns were identified, in Asian subjects with moderate to severe plaque psoriasis.  相似文献   
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