PTEN和VEGFPCNAbcl-2在胃癌组织中的表达及相关性研究

目的通过对PTEN和血管内皮生长因子(vascularendothelialgrowthfactor,VEGF)、增生细胞核抗原(proliferatingcellnuclearantigen,PCNA)、bcl-2在胃癌中表达的研究,结合临床病理特征,探讨PTEN和VEGF、PCNA、bcl-2的相关性。方法应用免疫组织化学S-P法检测68例胃癌组织及20名正常胃黏膜中PTEN、VEGF、PCNA和bcl-2的表达。结果胃癌组织中PTEN蛋白表达率为47%(33/68),显著低于正常胃黏膜的表达100%(20/20)(P<0.01),与组织分化程度呈正相关(P<0.01),与淋巴结转移呈负相关(P<0.05)。VEGF在胃癌中的表达率为75%(51/68),显著高于正常胃黏膜的表达10%(2/20)(P<0.01),与癌组织浸润深度呈正相关(P<0.01),与淋巴结转移也呈正相关(P<0.05),与组织分化程度无关。PCNA在胃癌中的表达率为74%(50/68),显著高于正常胃黏膜的表达20%(4/20),与癌组织浸润深度呈正相关(P<0.01),与淋巴结转移呈正相关(P<0.05),与组织分化程度呈负相关(P<0.05)。bcl-2在胃癌中的表达率为54%(37/68),显著高于正常胃黏膜的表达5%(1/20)(P<0.01),与癌组织浸润深度、淋巴结转移及组织分化程度无关。PTEN在胃癌中的表达与VEGF、PCNA呈负相关(P<0.01)。结论PTEN失活或蛋白表达降低与胃癌的组织分化程度及淋巴结转移密切相关,且与VEGF、PCNA呈显著负相?     

PS2、COX2、CerbB2在乳腺癌中表达的研究

目的研究ER、PR与PS2、COX2、CerbB2在乳腺癌组织中的表达,探讨与病理类型、淋巴转移、内分泌治疗及预后的关系。方法采用免疫组化SP检测54例乳腺癌组织中COX2、CerbB2、PS2、ER、PR的表达。结果COX2、CerbB2在乳腺癌组织的表达的阳性率与肿瘤的大小、发病年龄肿瘤分级及淋巴转移有关,（P〈0.05）,在高分化癌中低表达,在低分化癌中高表达,在淋巴结转移组织中两者都高表达。PS2在ER、PR阳性的癌组织中高表达,与肿瘤的大小、发病年龄、淋巴结转移无明显的关系,但与肿瘤的分化程度有关,在高分化癌中高表达,在低分化癌中低表达。结论PS2、ER、PR三项指标全阳性可预测乳腺癌患者辅助内分泌治疗疗效的可靠指标;COX2、CerbB2可作为判断预后的指标。     

Carcinogenicity and nephrotoxicity of 2-amino-, 1-amino- 2-methyl-, and 2-methyl-1-nitro-anthraquinone

2-Aminoanthraquinone (AA), l-amino-2-methylanthraquinone (l-Am-2-MeA), and 2-methyl-l-nitroanthraquinone (2-Me-1-Na) were tested for carcinogenicity in Fischer 344 rats and B6C3F₁ mice. In rats, all the 3 chemicals increased the incidence of hepatocellular neoplasms. Renal neoplasms were increased with 1-Am-2-MeA, and 2-Me-1-NA increased the incidence of subcutaneous fibromas in a dose-related manner. In mice, incidences of hepatocellular carcinomas were increased with feeding of AA, and 2-Me-l-NA increased the incidence of subcutaneous hemangiosarcomas. 1-Am-2-MeA did not appear to be carcinogenic in the mouse. Nephrotoxicity was associated with feeding of AA to female rats and 1-Am-2-MeA to mice.     

Comparative cytotoxicity study of enniatins A, A1, A2, B, B1, B4 and J3 on Caco-2 cells, Hep-G2 and HT-29

Enniatins (ENs) are ionophoric, phytotoxic, antihelminthic, and antibiotic compounds of hexadepsipeptidic structure produced by several strains of Fusarium spp. The cytotoxicity effect of the ENs A, A₁, A₂, B, B₁, B₄ and J₃ was compared on three tumor cell lines, the human epithelial colorectal adenocarcinoma (Caco-2), the human colon carcinoma (HT-29), and the human liver carcinoma (Hep-G2). The endpoint evaluated was the mitochondrial integrity by using the MTT assays, after 24 and 48 h of incubation. The IC₅₀ value for EN A₂ on Caco-2 cells, after 24 h exposure, was 18.7 ± 4.5 μM and decrease to 2.6 ± 0.7 μM at 48 h of incubation. However, ENs A, A₁, B₁ and B₄ exert pronounced cytotoxic effects in all the cell lines tested by the MTT assay after 24 and 48 h of incubation. The EN A₁ demonstrated to be the most cytotoxic ENs tested. Moreover, no statistical differences were found between the IC₅₀ values obtained for EN A₁ on Caco-2, HT-29 and Hep-G2, with IC₅₀ values ranging from 9.1 ± 2.2 μM to 12.3 ± 4.3 μM at 24 h and decreasing in a range variable from 1.4 ± 0.7 μM to 2.7 ± 0.8 μM at 48 h. On the other hand, EN A, B₁ and B₄ showed lower cytotoxicity, but in a similar range as the IC₅₀ values reported on HT-29 (IC₅₀ values (24 h): 16.8 ± 4.3-26.2 ± 6.7 μM), Caco-2 (IC₅₀ values (24 h): 19.5 ± 4.1 μM) and Hep-G2 (IC₅₀ values (24 h): 23.4 ± 5.6-26.2 ± 7.6 μM) cells. Cytotoxic effect with a 48 h of incubation revealed also a significant toxicity of ENs A (IC₅₀ values ranged from 8.2 ± 1.8 to 11.4 ± 4.6 μM), B₁ (IC₅₀ values variables from 3.7 ± 0.7 to 11.5 ± 5.3 μM) and B₄ (IC₅₀ of 4.5 ± 2.9-15.0 ± 4.0 μM). In summary, this study demonstrated that ENs can exert toxic activity at low micromolar concentrations in mammalian cells.     

Synthesis of deuterated herbicidal ZJ0273, ZJ0702, ZJ0777, and SIOC0163

ZJ0273 (propyl 4‐(2‐(4,6‐dimethoxypyrimidin‐2‐yloxy)benzylamino)benzoate), ZJ0702 (isopropyl 4‐(2‐(4,6‐dimethoxypyrimidin‐2‐yloxy)benzylamino)benzoate), ZJ0777 (2‐bromo‐N‐(2‐(4,6‐dimethoxypyrimidin‐2‐yloxy)benzyl)aniline), and SIOC0163 (5‐bromo‐N‐(2‐(4,6‐dimethoxypyrimidin‐2‐yloxy)benzyl)pyridin‐2‐amine) are active ingredients in oilseed rape herbicides. The middle aromatic ring‐deuterated form of ZJ0273 was synthesized from (²H₆)phenol and have been successfully used as tracer in its metabolism and degradation study. The methoxyl‐deuterated forms of four ingredients were synthesized from (²H₄)methanol, respectively, and they could be used as internal standards in quantitation of herbicide residue in rapeseed and its downstream foodstuff by using HPLC‐MS/MS. Copyright © 2010 John Wiley & Sons, Ltd.     

MMP-2、MMP-14、TIMP-2在退变腰椎间盘髓核组织的表达及意义

目的探讨基质金属蛋白酶-2（MMP-2）、基质金属蛋白酶-14（MMP-14）和金属蛋白酶组织抑制剂-2（TIMP-2）在退变腰椎间盘髓核组织表达的意义。方法应用免疫组织化学法检测36例退变腰椎间盘髓核组织（退变组）、20例腰椎骨折腰椎间盘髓核组织（对照组）MMP-2、MMP-14和TIMP-2表达。结果退变组MMP-2、MMP-14表达明显高于对照组（P〈0.001）,TIMP-2表达无明显改变（P〉0.05）;椎间盘退变等级与MMP-2、MMP-14及TIMP-2表达呈正相关（分别rs=0.710,P〈0.001;rs=0.617,P〈0.001;rs=0.406,P=0.014）;MMP-2与MMP-14、TIMP-2表达呈正相关（分别rs=0.665,P〈0.001;rs=0.516,P=0.001）。结论 MMP-2、MMP-14和TIMP-2表达加强可能是导致椎间盘退变的重要原因之一。     

Intestinal absorption mechanisms of berberine,palmatine, jateorhizine,and coptisine: involvement of P-glycoprotein

1. The absorption and transport mechanisms of berberine, palmatine, jateorhizine, and coptisine were studied using a Caco-2 cells uptake and transport model, with the addition of cyclosporin A and verapamil as P-glycoprotein (P-gp) inhibitors and MK-571 as a multidrug resistance-associated protein 2 (MRP₂) inhibitor.

2. In the uptake experiment, berberine, palmatine, jateorhizine, and coptisine were all taken into Caco-2 cells, and their uptakes were increased in the presence of cyclosporin A or verapamil.

3. In the transport experiment, P_app (AP-BL) was between 0.1 and 1.0?×?10⁶ cm/sec for berberine, palmatine, jateorhizine, and coptisine and was lower than P_app (BL-AB). ER values were all >2. Cyclosporin A and verapamil both increased P_app (AP-BL) but decreased P_app (BL-AB) for berberine, palmatine, jateorhizine, and coptisine; ER values were decreased by >50%. MK-571 had no influence on the transmembrane transport of berberine, palmatine, jateorhizine, and coptisine.

4. At a concentration of 1–100 μM, berberine, palmatine, jateorhizine, and coptisine had no significant effects on the bidirection transport of Rho123.

5. Berberine, palmatine, jateorhizine, and coptisine were all P-gp substrates; and at the range of 1–100 μM, berberine, palmatine, jateorhizine, and coptisine had no inhibitory effects on P-gp.

     

47例乳腺癌组织中ER与PR、pS2、C-erbB-2的表达及临床意义

目的探讨乳腺癌组织中ER与PR、pS2、C-erbB-2表达的临床意义。方法采用免疫组化S-P法检测47例术前未接受过化疗的原发性乳腺癌中ER与PR、pS2、C-erbB-2的表达。结果PR、pS2与ER的表达呈正相关。pS2的表达与组织学分级及肿瘤大小呈反比，与患者年龄、淋巴结转移情况无相关性。C-erbB-2的表达与组织学分级及肿瘤大小成正比，与淋巴结转移情况无相关性。结论ER、PR、pS2与C-erbB-2联合运用可作为乳腺癌预后诊断的可靠指标。     

ATP敏感性钾通道开放剂吡那地尔增高Bcl-2表达而抑制PC12细胞缺血性凋亡

目的探讨ATP敏感性钾通道开放剂吡那地尔对缺血缺氧PC12细胞凋亡及对Bcl-2 mRNA和蛋白表达的影响。方法取传代后3d的PC12细胞,分为正常对照组、缺血对照组、吡那地尔处理组、吡那地尔+格列吡嗪处理组共4组。吡那地尔处理组在PC12细胞缺血缺氧前20min加入浓度为100μmol·L-1的吡那地尔;吡那地尔+格列吡嗪处理组则加入浓度100μmol·L-1的吡那地尔和浓度为500μmol·L-1的KATP通道阻断剂格列吡嗪。采用Annexin-V FITC/PI双染流式细胞分析仪检测凋亡率;应用免疫荧光染色和Western blot检测Bcl-2蛋白表达水平;应用RT-PCR检测Bcl-2 mRNA表达水平。结果缺血缺氧后缺血对照组、吡那地尔处理组、吡那地尔+格列吡嗪处理组细胞凋亡率随时间增加而增加,24h达高峰。吡那地尔组与其余组比较差异均有显著性(P<0.01)。缺血对照组、吡那地尔处理组、吡那地尔+格列吡嗪处理组细胞Bcl-2 mRNA及蛋白表达各时间点均增加,12h达高峰。吡那地尔组与其余组比较差异均有显著性(P<0.05,或P<0.01)。缺血对照组和吡那地尔+格列吡嗪处理组比较差异均无显著性(P>0.05)。结论ATP敏感性钾通道开放剂可能通过提高Bcl-2 mRNA及蛋白表达来减轻缺血缺氧后PC12细胞凋亡,发挥保护作用。     

新型bcl-2反义寡核苷酸F951对人白血病裸鼠移植瘤的治疗作用

目的研究新型反义寡核苷酸F951对急性髓性白血病(AML)裸鼠移植瘤bcl-2基因表达、肿瘤生长及荷瘤鼠生存期的影响。方法体外大量扩增高表达bcl-2基因的HL60细胞,皮下接种建立AML裸鼠移植瘤模型,采取瘤体局部注射给药,观察F951及F951联合小剂量Ara-C对肿瘤生长及荷瘤裸鼠生存期的影响;应用荧光定量RT-PCR检测瘤细胞bcl-2mRNA表达;光镜观察瘤组织形态结构变化。结果治疗14d各组荷瘤鼠瘤体积、瘤重、瘤组织bcl-2mR-NA定量分别为:NS对照组(15.17±3.40)cm3、(12.69±0.92)g、9.79×104Copies.μg-1;无义寡核苷酸(FNS)组(15.91±3.77)cm3,(12.38±1.21)g;8.31×104Copies.μg-1;Ara-C组(1.24±0.55)cm3,(2.32±0.49)g,2.59×104Copies.μg-1;F951组(2.6±1.55)cm3,(3.53±0.67)g;1.01×10Copies.μg-1;F951+Ara-C组(0.62±0.48)cm3,(1.05±0.63)g,9.5×102Copies.μg-1;上述各组数据显示F951有下调肿瘤细胞bcl-2基因表达,抑制肿瘤生长的作用,抑瘤率为72.18%,与NS及FNS对照组比差异均有极显著性(P<0.01),F951联合Ara-C后治疗效果更佳,抑瘤率达91.73%,与Ara-C组相比差异有显著性(P<0.05)。瘤组织病理学检查:F951及F951联合Ara-C治疗组瘤细胞减少,瘤细胞变性坏死,大量纤维组织增生。各组动物生存期观察:NS对照组(13.67±0.82)d、,FNS组(13.50±1.22)d,Ara-C组(28.33±1.86)d,F951组(29.33±7.44)d,F951+Ara-C组(37.83±5.85)d。F951组及F951+Ara-C组生存期延长率分别为114.56%与176.71%,明显延长了荷瘤鼠的生存期(P<0.01)。结论F951能特异性地抑制AML裸鼠移植瘤细胞bcl-2基因表达,激活凋亡调控机制,诱导瘤细胞凋亡,同时增加化疗药物的敏感性,而发挥抗肿瘤作用。     

TRAIL、MMP-2及TIMP-2在大肠癌中的表达及意义的研究

目的研究肿瘤坏死因子相关凋亡诱导配体（TRAIL）、MMP-2、TIMP-2在大肠癌中的表达及意义,探讨TRAIL诱导肿瘤细胞凋亡的可能机制,MMP-2及TIMP-2在肿瘤的侵袭和转移中的重要的作用及相互关系,寻求提高TRAIL对肿瘤细胞敏感性的可能途径。方法采用SP法检测102例大肠癌及其癌旁5cm组织、25例正常大肠黏膜组织中TRAIL、MMP-2及TIMP-2蛋白的表达水平。结果 TRAIL在大肠癌、癌旁组织及正常大肠黏膜组织中的表达呈明显递增趋势（P〈0.01）;MMP-2在大肠癌、癌旁组织及正常大肠黏膜组织中的表达呈明显递减趋势（P〈0.01）;TIMP-2在大肠癌、癌旁组织及正常大肠黏膜组织中的表达无统计学意义（P〉0.05）。TRAIL在中、低分化癌中的表达明显低于高分化癌中的表达（P=0.003）。结论 TRAIL、MMP-2及TIMP-2可能与大肠癌的发生、发展、侵袭及转移密切相关;MMP-2与TIMP-2在癌组织中表达失衡在肿瘤的侵袭及转移中可能起重要作用。通过改善MMP-2与MMP-2在癌组织中表达的失衡,可能提高TRAIL对肿瘤细胞的特异性杀伤效率及改善肿瘤患者的预后。     

Dose-dependent inhibition of CYP1A2, CYP2C19 and CYP2D6 by citalopram,fluoxetine, fluvoxamine and paroxetine

Objectives: The purpose of this pharmacokinetic study was to investigate the dose-dependent inhibition of model substrates for CYP2D6, CYP2C19 and CYP1A2 by four marketed selective serotonin reuptake inhibitors (SSRIs): citalopram, fluoxetine, fluvoxamine and paroxetine. Methods: The study was carried out as an in vivo single-dose study including 24 young, healthy men. All volunteers had been identified as sparteine- and mephenytoin-extensive metabolisers. The volunteers received in randomised order, at weekly intervals, increasing single oral doses of one of the four SSRIs, followed 3 h later by sparteine (CYP2D6), mephenytoin (CYP2C19) and caffeine (CYP1A2) tests. Fluoxetine was given at 3-week intervals because of the long half-life of fluoxetine and its metabolite norfluoxetine. Citalopram, fluoxetine and paroxetine were given in doses of 10, 20, 40 and 80 mg and fluvoxamine was given in doses of 25, 50, 100 and 200 mg. Results: With increasing doses, there was a statistically significant increase in the sparteine metabolic ratio (MR) (P < 0.01, Page’s test for trend) for all four SSRIs. The increase was modest after intake of citalopram and fluvoxamine, while the increase was more pronounced after fluoxetine intake, although no volunteers changed phenotype from extensive metabolisers to poor metabolisers. Three of the six volunteers changed phenotype from extensive metabolisers to poor metabolisers after intake of 40 or 80 mg paroxetine. There was a statistically significant increase in the mephenytoin S/R ratio (P < 0.01, Page’s test for trend) with increasing doses of fluoxetine and fluvoxamine, but not after citalopram and paroxetine. However, no volunteers changed phenotype from extensive to poor metabolisers of S-mephenytoin. After intake of fluvoxamine, the urinary excretion of the metabolites related to N3 demethylation of caffeine were below the limit of quantification, whereas there were no significant changes in the urinary caffeine metabolic ratios after intake of the other three SSRIs. Conclusion: This investigation confirms that paroxetine and fluoxetine are potent inhibitors of CYP2D6, that fluvoxamine and fluoxetine are moderate inhibitors of CYP2C19 and that fluvoxamine is a potent inhibitor of CYP1A2 in humans in vivo. The clinical prediction of interaction from single-dose experiments may have to take the degree of accumulation during steady-state after multiple doses into account. Received: 11 December 1995/Accepted in revised form: 29 February 1996     

1, 5-二芳基取代-1, 2, 4-三唑类衍生物的合成、 抗炎活性及其构效关系研究

摘 要：目的 寻找高活性的选择性环氧合酶-2抑制剂，探讨其构效关系。方法 根据已上市的选择性环氧合酶-2抑制剂celecoxib的构效关系以及分子模拟研究的结果，设计了两类1,5-二芳基取代-1,2,4-三唑类衍生物，以1-(4-取代苯基)-3-硫代氨基脲为原料，经多步反应合成目标化合物；用小鼠二甲苯致炎模型对目标化合物进行体外抗炎活性测试。结果与结论 合成了22个未见文献报道的新化合物，所有目标化合物的结构经IR、¹H-NMR、MS谱和元素分析确证。生物活性研究表明，化合物I₃、I₉、I₁₂、I₁₅、II₂、II₃、II₆、II₇具有较强的抗炎活性（P<0.01），其中化合物II₂、 II₃、 II₆的抗炎活性最强。构效关系分析发现，在三唑环1位芳基的对位引入F、Cl、Br吸电子基团以及3位引入磺酰基和甲硫基，对抗炎活性有重要的意义；在三唑环5位芳基的对位引入氨磺酰基，对抗炎活性有较大影响。     

Noscapine,a possible drug candidate for attenuation of cytokine release associated with SARS-CoV-2

Successful treatment of viral infections has proven to be huge challenge for modern medicine with the most effective approach being prior vaccination. The problem with vaccination is the time it takes to develop an effective vaccine, validate its safety and manufacture it in large quantities. Facing Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), we simply do not have the time to develop the vaccine before thousands of people die. Therefore, any treatment which can decrease the severe symptoms due to lung damage may help attenuate mortality rates. Inactivation of ACE2 during virus fusion into the host cell may be one of the underlying reasons for intense immunological reaction seen in the lung tissue. This overreaction is probably mediated through the bradykinin receptor activation. Noscapine, a medication used for the treatment of cough, has been shown to inhibit bradykinin enhanced cough response in man. As it is already marketed in a number of countries as a cough medicine, even for children, a suitable formulation with all the required licenses is available that can be rapidly utilized in preliminary trials.     

新型合成水蛭肽Hirulog-s抗家兔弥散性血管内凝血的作用

目的:研究新型合成水蛭肽Hirulog-s抗弥散性血管内凝血(DIC)的作用。方法:采用凝血酶(100 U.kg-1×1 h)和氨基己酸(50 mg.kg-1×1 h)静脉滴注造成家兔急性DIC模型,观察给药前后家兔全血血小板计数(PLT)、血浆凝血酶原时间(PT)、纤维蛋白原(FIB)含量和血浆鱼精蛋白副凝固(3P)试验以及丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性,并采用放免测定法检测血浆血栓素(TXA2)和前列环素(PGI2)水平。结果:静脉注射高、中、低剂量(125.00,62.50,31.25μg.kg-1)Hirulog-s后DIC的抑制率用PT表示分别为69.72%,42.48%和24.48%;用PLT表示分别为62.13%,47.93%和31.52%;用FIB表示分别为66.73%,48.90%和28.19%;MAD含量显著下降,下降百分率分别为25.00%,14.47%和6.58%,SOD活性显著上升(P<0.01),上升百分率分别为198.52%,150.08%和42.05%;TXA2/PGI2比值显著下降(P<0.01),相同剂量的Hirulog-s的上述作用明显强于阳性对照药比伐卢定。结论:Hirulog-s具有明显的抗凝血酶诱发的DIC作用,其作用强于已上市同类药物比伐卢定。     

Cis-trans isomerization of the (5-nitro-2-furyl)acrylamide, AF-2, initiated by ascorbate, glutathione, Fe(II) and OH-

The cis-trans isomerization of the (5-nitro-2-furyl)acrylamide, AF-2, has been investigated using some important biological reducing agents to initiate reaction. Physiological concentrations of L-ascorbic acid, glutathione and iron(II) all accomplish isomerization in a catalytic manner over a period of minutes. Base-catalysed isomerization has also been observed. In all cases, the presence of oxygen severely inhibits isomerization. It is proposed that the mechanism involves a free-radical chain process; AF-2 or analogues are thus extremely sensitive probes for the generation of nitro radicals in biochemical reducing systems because of the high efficiency of isomerization.     

血清TLR2、PGE2、IL-6对自发性早产的预测价值研究

目的　探讨血清TOLL样受体2（TLR2）、前列腺素E2（PGE2）、白细胞介素-6（IL-6）对自发性早产（SPB）的预测价值。方法　收集2019年3月至2020年3月于济南市妇幼保健院产检具有早产高危因素的孕妇289例,其中有21例SPB、263例足月产、3例治疗性早产、1例晚期流产、1例失访,最终纳入284例。研究组21例（SPB）,分娩孕周（34.08±2.16）周;对照组263例（足月产）,分娩孕周（39.25±1.11）周。比较两组临床资料,行TLR2、PGE2及IL-6检测。计量资料符合正态分布,以均值±标准差（x±s）描述,采用独立样本t检验,计数资料比较采用χ²检验,采用多因素logistic回归模型分析SPB的独立预测因子,应用受试者工作特征曲线（ROC）评估血清TLR2、PGE2及IL-6对SPB的预测价值。结果　研究组血清TLR2、PGE2、IL-6水平均高于对照组（t=8.971、5.813、5.228,均P<0.05）。logistic回归分析显示,TLR2、PGE2和IL-6的比值比分别为1.590、1.714、1.501,是SPB的独立预测因子（均P<0.05）。ROC分析显示,TLR2、PGE2和IL-6预测SPB的曲线下面积分别为0.895、0.807和0.900,以IL-6的预测价值最大（灵敏度为90.48%,特异度为77.78%）。结论　血清TLR2、PGE2、IL-6均是SPB的独立预测因子,以IL-6的预测价值较高。     

可逆性胆碱酯酶抑制剂的研究:2-氧化-1,3,2-二氧磷杂环己烷类化合物的合成

本文报道2-氧化-1,3,2-二氧磷杂环己烷类衍生物的合成,希望寻找效果较好的可逆性胆碱酯酶抑制剂。初步药理实验证明,所合成的大部分化合物具有一定的抑制乙酰胆碱酯酶的作用,且毒性较低。通过对中间体Ⅱ进行质谱分析,发现该类化合物中大部分存在M-57碎片离子峰,利用高分辨质谱和亚稳离子测定,确定了该碎片离子的生成过程。