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91.
摘 要 目的: 参考《欧洲药典》的HPLC 脉冲安培电化学法建立高效液相色谱 柱后衍生化法测定庆大霉素C组分含量及其有关物质, 同时与电化学法进行比较研究。方法: 采用亲水性HydrosphereC18(250 mm×4.6 mm,5 μm)色谱柱,以含0.7%三氟乙酸及0.025%五氟丙酸的50 mmol·L-1氢氧化钠溶液(pH2.6)-乙腈(98.5∶1.5)为流动相。衍生化法反应温度30℃,荧光激发波长340 nm,发射波长430 nm。电化学法采用脉冲安培检测器,金电极为工作电极,四电位波形工作模式。结果:两种方法测定的庆大霉素C组分(C1a, C2, C2a和C1)分别在5.82~233.00,6.92~277.00,4.00~160.00和6.23~249.00 μg·mL-1的浓度范围内线性关系良好(r均≥0.999 3),检测限和定量限范围分别为0.92~3.28 ng和1.37~5.19 ng。结论: 两种方法的检测结果无明显差异。  相似文献   
92.
目的:建立厄贝沙坦原料药中9种残留溶剂(甲醇,乙醇,丙酮,异丙醇,乙腈,二氯甲烷,甲基叔丁基醚,乙酸乙酯及甲苯)的检测方法。方法:色谱柱为Kromat KB-624(30 m×0.53 mm,3.0μm);程序升温;载气为氮气,流速为5.0 ml·min-1;进样口温度为200℃;检测器为氢火焰离子化检测器,检测器温度为250℃;顶空进样,顶空瓶平衡温度为80℃,平衡时间20min。以二甲基亚砜为溶剂,用外标法测定9种残留溶剂的量,进样量为1 ml。结果:在本色谱条件下,9种残留溶剂分离良好。在各自的浓度范围内线性关系良好(r≥0.999 1),平均回收率为99.08%~105.14%,RSD为1.1%~3.3%(n=9);定量限分别为15.68,25.45,1.09,10.61,4.54,5.73,1.04,10.58,1.89μg。结论:本方法简便,准确,重复性好,可用于厄贝沙坦原料药中多种残留溶剂的同时测定。  相似文献   
93.
Significant evidence supports the role of the vestibular system in the regulation of blood pressure during postural movements. In the present study, the role of the vestibulo-spino-adrenal (VSA) axis in the modulation of blood pressure via the vestibulosympathetic reflex was clarified by immunohistochemical and enzyme immunoassay methods in conscious rats with sinoaortic denervation. Expression of c-Fos protein in the intermediolateral cell column of the middle thoracic spinal regions and blood epinephrine levels were investigated, following microinjection of glutamate receptor agonists or antagonists into the medial vestibular nucleus (MVN) and/or sodium nitroprusside (SNP)-induced hypotension. Both microinjection of glutamate receptor agonists (NMDA and AMPA) into the MVN or rostral ventrolateral medullary nucleus (RVLM) and SNP-induced hypotension led to increased number of c-Fos positive neurons in the intermediolateral cell column of the middle thoracic spinal regions and increased blood epinephrine levels. Pretreatment with microinjection of glutamate receptor antagonists (MK-801 and CNQX) into the MVN or RVLM prevented the increased number of c-Fos positive neurons resulting from SNP-induced hypotension, and reversed the increased blood epinephrine levels. These results indicate that the VSA axis may be a key component of the pathway used by the vestibulosympathetic reflex to maintain blood pressure during postural movements.  相似文献   
94.
B cell-activating factor of the TNF family (BAFF) is an essential B cell survival factor. However, high levels of BAFF promote systemic lupus erythematosus (SLE) in mice and humans. Belimumab (anti-human BAFF) limits B cell survival and is approved for use in patients with SLE. Surprisingly, the efficacy of rituximab (anti-human CD20) in SLE remains controversial, despite depleting B cells more potently than belimumab. This raises the question of whether B cell depletion is really the mechanism of action of belimumab. In BAFF transgenic mice, SLE development is T cell-independent but relies on innate activation of B cells via TLRs, and TLR expression is modulated by the BAFF receptor TACI. Here, we show that loss of TACI on B cells protected against BAFF-mediated autoimmune manifestations while preserving B cells, suggesting that loss of BAFF signaling through TACI rather than loss of B cells may underpin the effect of belimumab in the clinic. Therefore, B cell-sparing blockade of TACI may offer a more specific and safer therapeutic alternative to broad B cell depletion in SLE.  相似文献   
95.
《Vaccine》2015,33(30):3592-3599
BackgroundNew, more effective vaccines to prevent tuberculosis (TB) disease are needed urgently. H4:IC31 is an investigational vaccine that contains a fusion protein of the immunodominant antigens TB10.4 and Ag85B, formulated in IC31® adjuvant. We assessed the safety and immunogenicity of H4:IC31 in South African adults from a TB endemic setting.MethodsIn this double blind, placebo controlled, phase I trial, Mycobacterium tuberculosis-uninfected, HIV-uninfected, healthy adults with a history of childhood BCG vaccination were randomly allocated to two intramuscular vaccinations with 5, 15, 50 or 150 μg H4 formulated in 500 nmol IC31®, two months apart. Vaccinees were followed for six months to assess safety; immunogenicity was measured by ELISpot and intracellular cytokine staining assays.ResultsThirty-two participants received H4:IC31 and 8 received placebo. Injection site adverse events were common but mild; mild fatigue was the most common systemic adverse event. Frequencies of adverse events did not differ between dosage groups. Detectable antigen-specific CD4 T cell responses were induced by all doses of H4:IC31, but doses below 50 μg induced the highest frequencies of CD4 T cells, comprised predominantly of IFN-γ+TNF-α+IL-2+ or TNF-α+IL-2+ cells. These memory responses persisted up to the end of follow up, on study day 182.ConclusionsH4:IC31 demonstrated an acceptable safety profile and was immunogenic in South African adults. In this trial, the 15 μg dose appeared to induce the most optimal immune response.  相似文献   
96.
目的 建立一种用抑制电导离子色谱仪测定实验动物环境空气中氨的方法。方法 以稀硫酸作为吸收液采集空气中的氨,使氨在吸收液中转化为铵离子,选用抑制型电导检测器,CS12A阳离子分析柱,以甲磺酸作为淋洗液,通过测定吸收液中的铵离子的含量来计算空气中氨的浓度。结果 铵离子在0~1.00 μg/mL范围内具有良好的线性(r=0.9991),方法精密度高(RSD<6.38%),最低检出浓度为0.012 mg/m3,方法的平均回收率98.8%。结论 该法操作简便,无干扰离子影响,可作为实验动物环境空气中氨的测定方法。  相似文献   
97.
鉴于图书馆新生专栏建设的重要性,选取了39所"985工程"高校图书馆网站作为样本,调研图书馆新生专栏建设情况,发现共有15所高校图书馆网站开设了新生专栏,分析了这些高校图书馆网站新生专栏的位置、内容和形式等特点,介绍了清华大学图书馆、上海交通大学图书馆、中山大学图书馆等典型的新生专栏案例,并对图书馆新生专栏栏目设置、内容、形式等提出了相关建议。  相似文献   
98.
根据文献计量学的方法,对《中国妇幼健康研究》2011至2013年编发论文情况进行统计分析.分析载文量、栏目构成、第1作者年龄、学历及职称、第1作者研究方向、引文类型、基金项目资助等情况,以期了解期刊的刊文趋势和发展方向,为保证该刊学术质量及进一步提高刊物的整体质量提供参考.  相似文献   
99.
BACKGROUND & AIMS: In the absence of pathognomonic markers for Crohn's disease (CD) and ulcerative colitis (UC), the diagnosis of inflammatory bowel disease depends on a compendium of clinical, radiographic, endoscopic, and histologic criteria that bears imperfect specificity to the individual disorders. In 10% of cases of colitis, no differentiation can be made between CD and UC; these patients are diagnosed with indeterminate colitis (IC). We evaluated the value of anti-Saccharomyces cerevisiae antibodies (ASCA) and perinuclear antineutrophil cytoplasmic antibodies (pANCA) to increase diagnostic accuracy in categorizing IC. METHODS: Since 1996, 97 patients with IC from 3 centers (Leuven, Lille, and Vienna) were enrolled, analyzed for pANCA and ASCA, and followed up prospectively. RESULTS: A definitive diagnosis has been reached for 31 of 97 patients (32%). In these patients, ASCA+/pANCA- correlated with CD in 8 of 10 patients, whereas ASCA-/pANCA+ correlated with UC in 7 of 11 patients. The remaining 4 cases became CD, clinically behaving as UC-like CD. Almost half of the patients (47 of 97 [48.5%]) were negative for ASCA and pANCA, and 40 remain diagnosed with IC to date. Only 7 seronegative cases (14.9%) became CD or UC compared with 48% (24 of 50) of seropositive patients (P < 0.001). CONCLUSIONS: Results so far show that ASCA+/pANCA- predicts CD in 80% of patients with IC and ASCA-/pANCA+ predicts UC in 63.6%. Interestingly, 48.5% of patients do not show antibodies against ASCA or pANCA. Most of these patients remain diagnosed with IC during their further clinical course, perhaps reflecting a distinct clinicoserological entity.  相似文献   
100.
The dorsal column nuclei complex (DCN‐complex) includes the dorsal column nuclei (DCN, referring to the gracile and cuneate nuclei collectively), external cuneate, X, and Z nuclei, and the median accessory nucleus. The DCN are organized by both somatotopy and modality, and have a diverse range of afferent inputs and projection targets. The functional organization and connectivity of the DCN implicate them in a variety of sensorimotor functions, beyond their commonly accepted role in processing and transmitting somatosensory information to the thalamus, yet this is largely underappreciated in the literature. To consolidate insights into their sensorimotor functions, this review examines the morphology, organization, and connectivity of the DCN and their associated nuclei. First, we briefly discuss the receptors, afferent fibers, and pathways involved in conveying tactile and proprioceptive information to the DCN. Next, we review the modality and somatotopic arrangements of the remaining constituents of the DCN‐complex. Finally, we examine and discuss the functional implications of the myriad of DCN‐complex projection targets throughout the diencephalon, midbrain, and hindbrain, in addition to their modulatory inputs from the cortex. The organization and connectivity of the DCN‐complex suggest that these nuclei should be considered a complex integration and distribution hub for sensorimotor information.  相似文献   
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