“以学生为中心”在中医基础理论教学中的运用体会

"以学生为中心"就是以学生的学习和发展为中心,本文探讨了在中医基础理论教学中如何运用这一理念,认为教师要始终考虑学生的知识现状,把握学生接受和学习中医的能力;引导学生不断进行自我认知,让学生逐步具备"自知之明";课堂上应主要运用启发式教学法,尤其应根据教学情景设置问题,以激发学生学习中医的兴趣。     

辣木叶及其有效成分抗高脂血症药理作用研究进展

辣木叶来源于热带植物辣木Moringa oleifera,以叶入药,具有良好的生理活性。现代研究显示辣木叶含有丰富的黄酮、多糖、多酚、生物碱等功能成分,具有明确的抗氧化、抗菌、降糖、抗高脂血症等药理作用。辣木叶及其有效成分可能通过抑制脂质过氧化、抑制胰脂肪酶活性、抑制α-葡萄糖苷酶活性、诱导棕色脂肪组织生成、提高胆汁酸结合能力等途径达到抗高脂血症作用。综述辣木叶及其有效成分抗高脂血症药理作用的研究进展,以期为利用该药用植物资源开发新药提供依据。     

Coupling between slow waves and sharp-wave ripples engages distributed neural activity during sleep in humans

Hippocampal-dependent memory consolidation during sleep is hypothesized to depend on the synchronization of distributed neuronal ensembles, organized by the hippocampal sharp-wave ripples (SWRs, 80 to 150 Hz), subcortical/cortical slow-wave activity (SWA, 0.5 to 4 Hz), and sleep spindles (SP, 7 to 15 Hz). However, the precise role of these interactions in synchronizing subcortical/cortical neuronal activity is unclear. Here, we leverage intracranial electrophysiological recordings from the human hippocampus, amygdala, and temporal and frontal cortices to examine activity modulation and cross-regional coordination during SWRs. Hippocampal SWRs are associated with widespread modulation of high-frequency activity (HFA, 70 to 200 Hz), a measure of local neuronal activation. This peri-SWR HFA modulation is predicted by the coupling between hippocampal SWRs and local subcortical/cortical SWA or SP. Finally, local cortical SWA phase offsets and SWR amplitudes predicted functional connectivity between the frontal and temporal cortex during individual SWRs. These findings suggest a selection mechanism wherein hippocampal SWR and cortical slow-wave synchronization governs the transient engagement of distributed neuronal populations supporting hippocampal-dependent memory consolidation.

Memory consolidation involves the transformation of newly encoded representations into long-term memory (1–3). During non-rapid eye movement (NREM) sleep, hippocampal representations of recent experiences are reactivated (4, 5), along with transient synchronization of distributed subcortical and cortical neuronal populations (6, 7). It is hypothesized that the oscillatory synchrony facilitates connections between the neuronal ensembles, stabilizing memory representations (8). The selection and synchronization of distant neuronal populations that participate in hippocampal-dependent memory consolidation are proposed to depend on the interaction between hippocampal sharp-wave ripples (SWRs, 80 to 150 Hz), traveling subcortical/cortical slow-wave activity (SWA, 0.5 to 4 Hz), and sleep spindles (SP, 7 to 15Hz), but the underlying mechanisms subserving this network engagement are unclear. Here, we investigated how hippocampal SWRs and subcortical/cortical slow waves and spindles coordinate distributed neuronal populations during memory consolidation in NREM sleep.Hippocampal SWRs are transient local field potential oscillations (20 to 100 ms; 80 to 150 Hz in humans) implicated in planning, memory retrieval, and memory consolidation (9). Several lines of evidence highlight the role of SWRs in sleep-dependent memory consolidation. First, memory reactivation in the hippocampus, cortical, and subcortical structures peaks during SWRs (4–7, 10, 11). Second, hippocampal–subcortical/cortical functional connectivity, the prerequisite for binding of anatomically distributed reactivated memory traces is enhanced around SWRs (7, 12–15). Finally, SWR suppression interferes with, while prolongation of SWR duration improves hippocampal-dependent memory consolidation (16, 17).While research converges on the notion that SWR output modulates neuronal activity across brain regions during NREM sleep, SWR events are temporally biased by phases of SWA and SWA-nested SP (18–20). SWA and SP are present in cortical and subcortical structures (21, 22), originate in frontal areas, and traverse in an orderly succession to temporal lobes and subcortical structures, including the hippocampus (18, 22–24). Indeed, SWA synchrony increases following learning, and the reduction of SWA synchrony is correlated with memory impairment (25). Finally, although SWA is ubiquitous, individual SWA trajectories are usually limited to a subset of cortical/subcortical areas, with ∼80% of these events detected in less than half of recorded locations in humans (22). Therefore, each SWR-associated SWA event could recruit and index a unique sequence of cortical and subcortical populations.In this study, we used the broadband high-frequency activity (HFA, 70 to 200 Hz) recorded from human intracranial electrodes as a metric of subcortical/cortical activity. HFA is an indirect measure of multiunit spiking from the population surrounding the electrode contact (26), estimated in the range of several hundred thousand neurons. Consistent with the hypothesized role of SWR in synchronizing distributed memory traces, we found HFA power modulation during hippocampal SWR events in ∼30% of extrahippocampal recording sites. Given the critical role of SWA in facilitating hippocampal-dependent memory consolidation (13) and their confinement to local regions (22), we hypothesize that interplay between SWA and SWRs organizes hippocampal–cortical and cortical–cortical interactions during SWR events. Indeed, we found a strong association between SWR phase locking to extrahippocampal SWA or SP and HFA modulation in the same recording site. Interestingly, while the SWR–SWA phase locking was present bilaterally, the SWR–SP phase locking was limited to the hemisphere of SWR origin. These findings suggest that coupling between the hippocampal SWRs and extrahippocampal SWA/SP drives the selection of cortical populations to participate in hippocampal–cortical communication. In addition, theoretical constructs of memory consolidation predict transient synchronization of neuronal populations in distant cortical regions during hippocampal SWRs. Based on the widespread presence of SWA during NREM sleep, SWA–SWR temporal coupling, and ability of SWA to synchronize large cortical areas, we hypothesized that the pairwise phase relation between the SWA in different cortical locations could predict the functional coupling between the local cortical populations during SWR windows. In support of the cooperative role of SWR and SWA in orchestrating cortical–cortical communication, we found that SWA phase alignments between two distant cortical sites predicted their neuronal population synchronization during individual SWR windows, manifested by temporal HFA power correlations. The amplitude of individual SWRs was another strong predictor of cortico–cortical coupling, while the combination of SWA phase difference and SWR amplitude outperformed the predictive accuracy of the phase difference or SWA amplitude individually. These results imply a recruitment mechanism by which interplay of SWA and SWRs provides communication windows for long-range interactions between distributed neuronal populations, critical for hippocampal-dependent memory consolidation.     

自发性细菌性腹膜炎的分子诊断研究进展

自发性细菌性腹膜炎(SBP)是终末期肝病最常见的感染类型,SBP的诊断和治疗面临着很大的困难和挑战。近些年来,分子诊断技术尽管获得了极大的进步,但未广泛应用于临床实践。本文根据SBP的诊断现状,综述分子微生物诊断方法在SBP诊断上的进展,单纯细菌定性并不能明确细菌DNA与临床表现的关系,细菌定量结合其类型更能准确描述SBP的生物学特征,可为SBP及其特殊类型的诊断和指导抗菌药物的应用提供可能。     

归脾汤加减联合美托洛尔治疗快速型心律失常的Meta分析

目的系统评价归脾汤加减联合美托洛尔治疗快速型心律失常的有效性及安全性,为其临床应用提供循证医学证据。方法计算机检索中国知网(CNKI)、维普(VIP)、万方数据库、PubMed、EMbase数据库中已公开发表的随机对照研究,依据纳入和排除标准对相关文献进行筛选,按照改良Jadad量表和Cochrane手册对纳入的研究进行质量评价和偏倚风险评估,运用Rev Man5.2软件对纳入的文献进行Meta分析。结果最终纳入14篇文献,共1200例病人。Meta分析结果显示,试验组(归脾汤加减联合美托洛尔治疗)临床症状改善[OR=5.05,95%CI(3.46,7.37),P<0.00001]、心电图改善[OR=4.46,95%CI(2.34,8.50),P<0.00001]、中医症状积分[MD=-3.89,95%CI(-4.41,-3.36),P<0.00001]均优于对照组(单纯美托洛尔治疗),两组不良反应发生率比较差异无统计学意义[OR=0.46,95%CI(0.21,0.99),P=0.05]。结论现有证据表明,在应用美托洛尔的基础上加用中药归脾汤较单纯使用美托洛尔治疗快速型心律失常具有更好的有效性。     

乳腺细针针吸细胞学检查在基层医院应用的可行性分析

目的 分析基层医院乳腺细针针吸细胞学(fine needle aspiration cytology,FNAC)诊断的准确性,评价该检查方法在基层医院应用的可行性.方法 回顾北京市怀柔区中医医院有组织病理学结果的145例乳腺肿物细针针吸病例,将细胞学结果与组织学结果对照分析.结果 145例乳腺针吸病例中乳腺癌27例,纤维腺瘤45例,乳腺腺病40例,其他良性病变33例.针吸细胞学诊断乳腺癌的敏感性为92.6％,特异性为100％,准确性为98.6％.结论 FNAC检查操作简便,诊断准确性高,可以作为基层医院乳腺肿物的常规检查项目.     

鼻翼基底细胞癌手术Ⅰ期修复的探讨

目的探讨侵犯鼻翼软骨的鼻翼基底细胞癌手术Ⅰ期修复的合适方式。方法根据鼻翼缺损的范围、浸润深度对19例鼻翼基底细胞癌采用游离耳廓复合组织瓣和耳廓复合组织瓣联合鼻唇沟皮瓣两种方法进行Ⅰ期修复,并进行随访,分析两种修复方法在鼻翼缺损修复中的优缺点。结果全部病例均手术成功,无皮瓣整体坏死出现。联合修复的12例患者术后均未出现移植物皮肤颜色改变和水疱形成的情况。有1例术后6个月时出现鼻孔边缘粘连导致狭窄,经再次手术恢复正常;1例鼻孔稍外翻。单纯游离耳廓复合组织瓣修复的7例患者中有1例部分组织瓣皮肤有缺血。结论对缺损面积较大（1×1.5cm2～2.0×2.5cm2）、侵犯鼻前庭皮肤的病例可以采用耳廓复合组织瓣联合邻近转移皮瓣进行鼻翼全层修复,而对缺损面积小于1×1.5cm2的病例可以单纯采用耳廓复合组织瓣进行修复。     

苦参碱对人食管癌细胞株Eca-109增殖和凋亡的影响

目的探讨中药提取物苦参碱单体(Matrine)对人食管癌细胞株Eca-109的诱导凋亡和抑制增殖作用。方法体外培养人食管癌细胞株(Eca-109),分别给以不同浓度的苦参碱对体外培养的Eca-109细胞株进行干预。以MTT比色法、Hoechst33342染色法以及流式细胞术测定苦参碱对Eca-109细胞株的诱导凋亡及抑制增殖的作用。结果 MTT实验显示苦参碱可以明显抑制Eca-109细胞株的增殖,流式细胞术检测细胞周期显示G2期细胞明显增多,S期细胞显著减少。结论苦参碱能明显抑制Eca-109细胞株的增殖,促进其凋亡,其作用机制可能与细胞周期阻滞于G2期有关。     

高效液相色谱-质谱联用法测定姜黄素在大鼠体内的分布

目的:采用高效液相色谱-质谱联用法,测定姜黄素在大鼠血浆和组织中药物浓度随时间变化的分布规律及药物代谢动力学的特点。方法:大鼠口服灌胃姜黄素后,收集血浆和组织样品,通过有机溶剂乙酸乙酯分离提取,采用高效液相色谱-质谱联用法分析,选择C18色谱分析柱,乙腈（85%）和水(5%)为流动相,检测血浆和组织中的姜黄素药物浓度。质谱条件为电喷雾电离正离子方式(ESI＋),多反应监测(MRM)模式。结果:姜黄素在血中的达峰时间为0.5 h,曲线下面积(AUC)为(236±6)ng?h/mL,峰值血药浓度为(91±5)ng/mL;心脏中的达峰时间为1 h,肝脏和肾脏中的达峰时间均为2 h。在心脏和肝脏中,曲线下面积(AUC)分别为(127±3)ng?h/mL和(166±5)ng?h/mL,均显著高于其他组织。结论:我们建立的高效液相色谱-质谱联用分析方法,可有效监测姜黄素在血中或组织器官中药物浓度随时间变化的规律,此方法简便、重复性高、灵敏度强。大鼠口服姜黄素后,可被吸收入血,组织器官分布广泛。     

DC细胞在辐射损伤抗原递呈及T细胞活化中的作用

目的 利用体外细胞共培养技术模拟体内肺组织微环境,探索树突状细胞（DC）在辐射损伤细胞的抗原提呈作用。方法 ⁶⁰Co γ射线照射的小鼠肺上皮细胞（MLE-12）与骨髓来源DC和/或脾T淋巴细胞培养48 h,流式细胞术检测DC细胞共刺激分子CD80/86和抗原肽识别复合物MHC Ⅰ/Ⅱ表达水平,T细胞活化标志CD69/28/152表达水平以及CD4⁺和CD8⁺亚群细胞数。结果 ⁶⁰Co γ射线照射的MLE-12细胞凋亡率呈剂量依赖性增高,明显刺激DC细胞CD80/86和MHC II表达,但对T细胞无直接活化作用;6 Gy照射的MLE-12细胞与DC细胞和T淋巴细胞共培养48 h,T细胞CD69和CD28表达增加,CD4⁺和CD8⁺亚群细胞数均明显高于对照组,同时DC细胞出现CD86和MHCI特异性高表达。结论 辐射损伤细胞可刺激DC细胞抗原提呈功能,并对T细胞进行活化。