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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.
To identify differentially expressed genes between obese individuals and normal control, we have undertaken suppression subtractive hybridization (SSH). Omental adipose tissues were obtained via abdominal surgery for appendicitis in both 13 obese subjects[BMI (body mass index) 〉 30 kg/m(2)] and 13 normal subjects (BMI 〉 18 and 〈 25 kg/m(2)).  相似文献   
3.
THEβ2-adrenergicreceptor(β2-AR)ishighlyexpre-ssedonairwaysmoothmusclecellsinlung,anddefectsinβ2-ARsignalpathwaywereinvolvedinthepathogenesisofasthma.1 Humanβ2-ARgeneisanintr-onlessgenewithacodingblockconsistingof1239nucleo-tidesonchromosome5q31-32,genome-widesearchforas-thmasusceptibilitylocishowedthatmarkersonthisregionhavebeenlinkedtoasthma-associatedphenotypesinvariousethnicpopulations.2 Reihsausetal3 firstdescribedninecod-ingregionpolymorphisms,particularly,thethreecommonaminoacidsu…  相似文献   
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5.
Histomorphometric study was made on a series of sections of undecalcified epiphyseal femoral specimens from rats with experimental fluorosis. The results revealed osteosclerosis in Group A (5 ppm) being more severe than that in Group B (25 ppm) With the increase of fluoride dose, the parameters fell down instead of increased in parallel. There is seemingly a threshold over which osteosclerosis in fluorosis becomes less severe. In contrast to Bely's conclusion the authors proposed that, fluoride toxi- city, besides decreasing the number of osteoblasts, may also activate the osteoblasts. The number of osteoblasts may be increased with relative lower dose of fluoride also. The net outcome is the in crement in bone volume. When toxic dose of fluoride is higher enough (higher than the proposed threshold), however, the number of osteoblasts and its activity are inhibited. So are the osteocytes. This interpretation may be the cytological basis for osteosclerosis in the experimental fluorosis.  相似文献   
6.
瘦素、骨保护素与骨代谢   总被引:5,自引:0,他引:5  
骨组织时刻处于骨重建的动态变化之中,即不间断的骨形成、骨吸收贯穿生命的始终。骨重建的范围非常广泛,几乎每10年成人骨骼完全再生一次。对于健康青年人,骨形成量与骨吸收量保持动态平衡。随着年龄增长,骨吸收日益占据优势,由此可导致骨质疏松等衰老性疾病的发生。骨重建的过程有赖于两大类细胞的活性:其一是成骨细胞,负责生成新骨(骨形成);其二是破骨细胞,负责破坏旧骨(骨吸收)。骨代谢研究中的主要问题就是研究成骨细胞和破骨细胞分化和活性的调控机制,以期实现骨重建的动态平衡,达到预防和治疗各种代谢性骨病的目的。…  相似文献   
7.
父子二代骨斑症(附一例报告及文献综述)高志红,邱明才,齐全乐,高玉琪,王维力,冯凭,陈宏骨斑症(osteopoikilosis),又称脆弱性骨硬化,是一种罕见的遗传性骨发育异常疾病。我院收治一例骨斑症病人同时有多种组织损害和先天畸形,更属罕见。我们对...  相似文献   
8.
原发性骨质疏松的诊断首先要除外继发性骨质疏松。后者包括的范围很广,内容也很多,需要广博的内科学基础和辨证的逻辑思维才能予以正确鉴别。骨密度检查只能作为一种参考,而不能作为诊断原发性骨质疏松的唯一依据。  相似文献   
9.
目的研究氟化物作用后破骨细胞样细胞凋亡过程中细胞凋亡配体Fas、FasLFasLigand和核因子NF-κB的表达变化。方法在培养基中分别加入不同浓度的氟化钠培养破骨样细胞,以免疫组织化学染色方法观察细胞的Fas、FasL和NF-κB表达。结果Fas、FasL在破骨样细胞表达量随培养基中氟化钠浓度增高而增高;NF-κB的表达量随培养基中氟化钠浓度增高而降低,两者均具有剂量依赖关系。结论在氟化钠所致的破骨细胞凋亡过程中,Fas,Fas-L的表达随氟化物浓度增高而加强;而核因子NF-κB的表达随氟化物浓度增高而减弱,两者都具有剂量依赖关系。  相似文献   
10.
Immune responses of lymphocyte populations during early phases of mycobacterial infection and reinfection have not been well characterized in humans. A non-human primate model of Mycobacterium bovis bacille Calmette-Guerin (BCG) infection was employed to characterize optimally the immune responses of mycobacteria-specific T cells. Primary BCG infection induced biphasic immune responses, characterized by initial lymphocytopenia and subsequent expansion of CD4+, CD8+ and gammadelta T cell populations in the blood, lymph nodes and the pulmonary compartment. The potency of detectable T cell immune responses appears to be influenced by the timing and route of infection as well as challenge doses of BCG organisms. Systemic BCG infection introduced by intravenous challenge induced a dose-dependent expansion of circulating CD4+, CD8+ and gammadelta T cells whereas, in the pulmonary compartment, the systemic infection resulted in a predominant increase in numbers of gammadelta T cells. In contrast, pulmonary exposure to BCG through the bronchial route induced detectable expansions of CD4+, CD8+ and gammadelta T cell populations in only the lung but not in the blood. A rapid recall expansion of these T cell populations was seen in the macaques reinfected intravenously and bronchially with BCG. The expanded alphabeta and gammadelta T cell populations exhibited their antigen specificity for mycobacterial peptides and non-peptide phospholigands, respectively. Finally, the major expansion of T cells was associated with a resolution of active BCG infection and reinfection. The patterns and kinetics of CD4+, CD8+ and gammadelta T cell immune responses during BCG infection might contribute to characterizing immune protection against tuberculosis and testing new tuberculosis vaccines in primates.  相似文献   
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