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1.
沙生蜡菊花中黄酮类成分的分离与鉴定   总被引:1,自引:0,他引:1  
目的研究沙生蜡菊(Helichrysum arenarium(L.)Moench)花的化学成分。方法采用硅胶柱色谱?ODS柱色谱和HPLC柱色谱分离纯化,依据理化性质、波谱数据分析进行结构鉴定。结果从沙生蜡菊花的甲醇提取物中分离得到8个黄酮类化合物,分别鉴定为山奈酚3-O-β-D-吡喃葡萄糖苷(kaempferol 3-O-β-D-glucopyranoside,1)、木犀草素3′-O-β-D-吡喃葡萄糖苷(luteolin3′-O-β-D-glucopyranoside,2)、木犀草素7-O-β-D-吡喃葡萄糖苷(luteolin7-O-β-D-glucopyranoside,3)、木犀草素6-羟基-7-O-β-D-吡喃葡萄糖苷(luteolin6-hydroxy-7-O-β-D-glucopyranoside,4)、木犀草素3′-甲氧基-6-羟基-7-O-β-D-吡喃葡萄糖苷(luteolin3′-methoxyl-6-hydroxy-7-O-β-D-glucopyranoside,5)、黄芩素7-O-β-D-吡喃葡萄糖苷(scutellarein7-O-β-D-glucopyranoside,6)、山柰酚3-O-β-D-龙胆二糖苷(kaempferol3-gentiobioside,7)、山柰酚3-O-(3-β-D-吡喃葡萄糖基)-β-D-吡喃葡萄糖苷(kaempferol3-O-(3-β-D-glucopyranosyl)-β-D-glucopyranoside,8)。结论化合物2、4~8为首次从蜡菊属植物中分离得到。  相似文献   
2.
Abstract: We describe a 56-year-old woman with congenital hepatic fibrosis. Blood tests and liver scanning with Tc-99m-labelled galactosyl human serum albumin revealed mild liver dysfunction. Per-rectal portal scintigraphy with iodine-123 iodoamphetamine showed severe abnormalities in the portal circulation, and the portal pressure measured during percutaneous transhepatic portography was high (350 mmH2O). Idiopathic portal hypertension was suspected. Laparoscopy disclosed diffuse, intense dendritic white markings around the liver. Congenital hepatic fibrosis was confirmed on histologic examination of a biopsy specimen obtained during laparoscopy. In summary, we report a rare and relatively elderly case of CHF, in which laparoscopy was useful in the diagnosis. (Dig Endosc 1999; 11: 174–178)  相似文献   
3.
The purpose of this study was to evaluate the effect of interruptionof the descending supraspinal sympathetic outflow on heart ratecontrol during exposures to chemical stimuli. We investigatedthe heart rate responses to progressive isocapnic hypoxia andhyperoxic hypercapnia using the rebreathing technique and quantifiedthe relationship between heart rate (HR), oxygen saturation(SaO2), alveolar PCO2 (PACO2), and minute ventilation (VE) in16 chronic tetraplegic subjects with low cervical spinal cordtransection. The HR responses were determined from the linearslopes of HR on SaO2 and HR on PACO2. We found that mean restingheart rate was within normal range; 66 ±3 (SEM) beatsmin–1. HR increased as oxygenation fell or CO2 tensionrose. The mean tetraplegic HR/SaO2 was 0.83 ± 0.14 beatsmin–1 per 1% fall in SaO2 and that of HR/PACO2 was 0.30± 0.13 beats min–1 per mmHG rise in PACO2. TheHR and VE responses to either hypoxia or hypercapnia were relatedin the tetraplegic subjects. We conclude that the stimulatoryHR reponses to chemical stimuli are not suppressed by cervicalspinal cord transection. Thus, the descending sympathetic activitydoes not underlie the HR acceleration by chemical stimuli.  相似文献   
4.
SUMMARY Adhesive bonding of a mica-based castable ceramic material (Olympus Castable Ceramics, OCC) was evaluated in vitro with the use of a silane primer in conjunction with an adhesive luting material. The primer contained a silane coupler and 4-methacryloxyethyl trimellitate anhydride (4-META), while the methyl methacrylate (MMA)-based luting agent was initiated with a tri-n-butylborane derivative (TBB) and contained 4-META (4-META/MMA-TBB resin). Ceramic specimens were sanded with No. 600 silicon carbide paper followed by blasting with alumina and/or etching with ammonium bifluoride. The specimens were bonded with various combinations and shear bond strengths were determined. Both priming and alumina blasting enhanced the bond between 4-META resin and OCC. Although etching with ammonium bifluoride roughened the ceramic surface, this procedure did not improve the bond strength. Electron probe microanalysis of the ceramic surface revealed a decrease in silicon and aluminium elements after etching with ammonium bifluoride.  相似文献   
5.
Abstract: A setrospective study to determine the influence of prophylactic endoscopic sclerotherapy on the survival rate of patients with hepatocellular carcinoma complicated by esophageal varices was conducted. The subjects included 132 patients without esophageal varices at the time of diagnosis (NV group), 37 patients with hepatocellular carcinoma for whom prophylactic sclerotherapy had been performed for risky esophageal varices (PS group) and 26 patients with hepatocellular carcinoma and risky varices for whom prophylaxis was not performed (NPS group). Multiple regression analysis was used to identify factors affecting the survival rate of the 132 patients without esophageal varices. A tumor embolus in the primary branch or main trunk of the portal vein adversely affected long-term survival in these patients. The patients were further divided into 2 subgroups, namely those with (Vp3) and without (Vp0-Vp2) tumor emboli in the main trunk and primary branch of the portal vein. In the Vp0– Vp2 emboli subgroup, the patients who received prophylactic sclerotherapy and the patients without varices had similar survival rates. Patients without prophylactic sclerotherapy had a significantly shorter survival rate than the group without varices and the prophylactic sclesotherapy group (p<0.01 and p<0.05). A significant bleeding rate was observed in the group without prophylaxis and not in the group with prophylaxis. However, in the Vp3 subgroup, the survival rate in each group was identical. Thus prophylactic variceal sclerotherapy is indicated for patients with hepatocellular carcinoma who do not have tumor emboli in the main trunk or primary branch of portal vein.  相似文献   
6.
A quantitative and qualitative change in inflammatory cells in the lungs of mice after intratracheal inoculation of heat-killed Cryptococcus neoformans was examined by direct analysis of the pulmonary intraparenchymal leucocytes. Macrophages and T and B lymphocytes increased, peaked at day 7, and then gradually decreased to the basal level, Macrophages were activated 7 days after the inoculation, as indicated by the enhanced expression of MHC class II, intercellular adhesion molecule-1 (ICAM-I)and Fc receptor (FcR), which have been known as their activation markers. T cells were also activated, as indicated by the induction of IL-2 receptor (IL-2R) and the enhanced expression of leucocyte function-associated molecule-1 (LFA-1) and ICAM-1, a pair of adhesion molecules which have also been regarded as T cell activation markers. CD4+ T cells preferentially accumulated in lungs, and proliferated in vitro by stimulation with heat-killed whole yeast cells, suggesting that at least some of the infiltrated T cells expand locally in response to the organisms. These results demonstrate that the activation of macrophages and T cells reactive to C. neoformans is induced in lungs after intratracheal inoculation of heat-killed organisms, and suggest that these cells interact to eliminate organisms more efficiently from the host.  相似文献   
7.
8.
Endovascular coil embolization for intracranial aneurysms, arteriovenous malformations (AVMs), dural arteriovenous fistulas (AVFs), and hypervascular tumors are recognized as an effective adjunctive or curative treatment. In this setting, it is sometimes difficult to navigate a coil delivery microcatheter to the target point of a tiny, tortuous vessel. We herein present a case series of a novel method that enabled super-selective coil embolization using an extremely soft bare, electrodetachable coil (ED extrasoft® coil) through a liquid embolic delivery microcatheter (Marathon®). The Marathon® catheter was successfully placed at the target point of the tiny, tortuous vessel, and coil embolization was achieved in all 16 patients with 9 AVMs, 2 distal aneurysms, 2 AVFs, and 3 meningiomas. The primary ED extrasoft® coil and delivery wire have a very small radius, and the coil is rapidly detachable with an alarm notice from the generator even under Marathon® with one marker. We believe that this technique can provide safe and efficient embolization for selected patients.  相似文献   
9.
10.
Cytotoxic effects of mannosamine and free fatty acids on humanmalignant T-lymphoid cell lines derived from patients with T-cellleukemia were investigated. The combination of mannosamine andan unsaturated fatty acid (oleate or linoleate) produced morestriking cytotoxic effects on malignant lymphoid cells thanon normal human lymphocytes. The amino sugars glucosamine ormannosamine in the combination caused a synergistic cytotoxiceffect, while the other carbohydrates (N-acetylmannosamine,N-acetylglucosamine, or mannose) had little effect. On the otherhand, the effect of saturated fatty acids (palmitate or stearate)in the same system was nil. An unsaturated fatty acid (oleate)caused an increase in lipid fluidity of the surface membranein MOLT-4 lymphoid cells, which possess higher lipid fluidityin combination with mannosamine, while saturated fatty acidshad no effect on the fluidity properties of the membrane lipids(even in the presence of mannosamine). The relationship betweenmannosamine and unsaturated fatty acids in cytolysis was discussed.  相似文献   
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