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1.
A rapid and high selective ultra?performance liquid chromatography (UPLC) with tandem mass spectrometry method for simultaneous determination of six compounds including albiflorin, paeoniflorin, picroside I, picroside II, saikosaponin A, and saikosaponin D in rat plasma was developed and validated using butyl p-hydroxybenzoate as an internal standard. One-step direct protein precipitation with acetonitrile was used to extract the compounds from the rat plasma samples. Chromatographic separation was achieved using an ACQUITY UPLC BEH C18 column (100 mm × 2.1 mm, 1.7 µm) at a flow rate of 0.4 mL/min, using gradient mode containing 0.1% formic acid in water and acetonitrile were used as the Mobile phase A and B. Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify and quantify active components. Calibration curves showed good linearity (R2 > 0.9908) over a wide concentration range for all compounds. The intra- and interday precision (relative standard deviation) ranged 2.4%–7.0% and 2.6%–8.0%, respectively. The accuracy (relative error) was from ?13.0% to 13.2% at all quality control levels. The recovery ranged from 81.1% to 92.5%. The validated method was successfully applied to pharmacokinetic study in rats after oral administration of Qing Gan?Shu Yu?Fang. The results show that one can draw a conclusion that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo.  相似文献   
2.
INTRODUCTION: The financial responsibility in health sector was decentralizedfrom central and provincial governments to county and township governments. It was argued that a decentralized system without effective transfer payment mechanism has pushed the poverty area to more disadvantaged positions in economic development in general.  相似文献   
3.
胸腺内注射异基因抗原诱导鼠神经移植免疫耐受的实验研究   总被引:15,自引:0,他引:15  
目的探讨小鼠胸腺内注射异基因抗原在同种异体异基因坐骨神经移植免疫耐受中的作用。方法自供体小鼠C57BL/6的脾细胞中提取MHC抗原注人受体鼠Balb/c小鼠胸腺内,于2周后移植供体鼠坐骨神经。48只Balb/c小鼠随机分为4组,A组(胸腺内注射组)、B组(自体神经移植组)、C组(冷冻异体神经移植组)、D组(异体神经移植加用免疫抑制剂组)。于3周后进行电生理学、组织学、免疫学检测。结果A组运动神经传导速度(38.23m/s)与D组(36.39m/s)相比无显著性差异(P〉0.05),组织学、电镜、免疫学(混合淋巴细胞培养及迟发性超敏反应)检测结果均证实B组分别优于A组、D组和C组。结论胸腺内注射异基因MHC抗原可诱导大鼠对异体坐骨神经移植的特异性免疫耐受。  相似文献   
4.
Objective: To study the diagnostic value of T2^*-weighted first-pass perfusion imaging in breast tumors. Methods: We analyzed the magnetic resonance imaging (MRI) information along with the pathological and immunohistochemistry results. Magnetic resonance imaging was performed in 28 patients with breast tumor. The time to signal intensity curves were generated according to the T2^*-weighted first-pass perfusion imaging. The curve's maximal signal intensity drop rate and maximal signal intensity decrease time were analyzed and compared with the pathological diagnoses after surgery. Results: Malignant breast lesions showed higher maximal signal intensity drop rate (44.69% ± 17.07 vs. 17.22% ±7.49, P 〈 0.001) than benign lesions, but there was no significant difference of maximal signal decrease time between those two lesions (23.94 s ± 4.92 vs. 20.02 s ± 6.83, P 〉 0.05). Conclusion: The T2^*-weighted first-pass perfusion imaging has enough sensitivity and specificity in breast tumor diagnosis.  相似文献   
5.
Objective To investigate the possibility of inducing immune tolerance to vein trans-plantation in rats by intrathymic injection of allogene. Methods MHC antigen extracted from splenic cells of donor Wistar rats was intrathymically injected to recipients SD rats, and donor Wistar femur vein was transplanted after 2 weeks. Forty-eight SD rats were randomly divided into 4 groups: group A ( femur vein autograft) ,group B ( femur vein allograft) ,group C ( femur vein allograft with use of immunosuppressant), group D (intrathymus injection). Imaging, histology and immunological assays of these groups were carried out 2 weeks after the transplantation. Results Histologic parameters that were tested were better in group D than those in group B. The concentration of serum IFN-γ in group B was significantly higher than that in groups A, C and D [ ( 86. 707±10.928 ) ng/L vs (29.328±4. 170), (69.076±8.059) and (63.355± 4.895) ng/L respectively, P < 0.05 ]. The concentration of serum IL-4 in group B was obviously lower than in groups C and D [ (23.656±3.369) ng/L vs (29.425±4.174) and ( 31.000±4.659) ng/L re-spectively,P < 0.05 ]. Conclusion Intrathymus injection of allogenic antigen might induce specific im-mune tolerance to femur vein transplantation in rats.  相似文献   
6.
紧急纤维支气管镜在老年高危患者中的应用   总被引:1,自引:0,他引:1  
目的 研究紧急纤维支气管镜 (纤支镜 )在老年高危患者中的应用。方法 老年急危重症患者 77例 ,其中急性生理和慢性健康评估 (APACHEⅡ )计分 >14分者 65例。所有患者共行 10 2例次紧急纤支镜操作 ,其中肺泡灌洗、气道分泌物吸引 76例次 ;纤支镜引导下经鼻气管插管 19例次 ;异物吸出 6例次。结果  10 2例次紧急纤支镜操作抢救总有效率为 80 .3 % ,无危及生命的并发症发生。结论 紧急纤维支气管镜是抢救急危重症患者呼吸道病变紧急处理的有力武器 ,高龄严重心、肺功能障碍不是纤支镜操作的禁忌证  相似文献   
7.
不同强度直流电刺激器对鼠坐骨神经再生的影响孟庆刚,于钟毓,岳琦,杨桂兰,孙立国,邢燕,李文庆尽管目前已证实直流电刺激可有效地促进鼠周围神经损伤的再生,但有关最佳刺激电流强度的确定仍是实验中尚未解决的难题。本实验通过应用不同强度全置入式弱直流电刺激器,...  相似文献   
8.
9.
Meng Q  Chen W 《Planta medica》1988,54(1):48-49
A new 6-oxygenated coumarin, pygmaeoherin, was isolated from roots of PYGMAEOPREMNA HERBACEA. Its structure was determined by spectroscopic methods. An NOE experiment played an important role in confirming the structure.  相似文献   
10.
Globoid cell leukodystrophy (GLD, Krabbe disease) is a severe demyelinating disease caused by a genetic defect of beta-galactocerebrosidase (GALC). To date treatment to GLD is limited to hematopoietic stem cell transplantation. Experimental approaches by means of gene therapy in twitcher mouse, an authentic murine model of human GLD, showed significant but only marginal improvements of the disease. To clarify whether the introduction of GALC could provide beneficial effects on the oligodendrocytes in GLD, we transduced twitcher oligodendrocytes by stereotactically injecting recombinant retrovirus encoding GALC-myc-tag fusion gene into the forebrain subventricular zone of neonatal twitcher mouse. In vivo effects of exogenous GALC on twitcher oligodendrocytes were studied histologically by combined immunostaining for the myc-epitope and the oligodendroglial specific marker, pi form of glutathione-S-transferase, at around 40 days of age. We show here that GALC transduction led to dramatic morphological improvement of the twitcher oligodendrocytes comparing with those in untreated twitcher controls. This study provided direct in vivo evidence that GALC transduction could prevent or correct aberrant morphology of oligodendrocytes in GLD which may be closely related to the dysfunction and/or degeneration of oligodendrocytes and the demyelination in this disease.  相似文献   
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