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排序方式: 共有367条查询结果,搜索用时 4 毫秒
81.
小藤铃儿草的生物碱成分 总被引:1,自引:0,他引:1
自小藤铃儿草Dactylicapnos torulosa(Hook.f ct Thomas.)Hutchins中分得六个单体,通过UV,IR,MS,~1HNMR和~(13)CNMR解析,鉴定了四个,其中一个为新化合物,命名为紫金龙碱(zijinlongine,Ⅰ),其他三个为已知化合物:氯化1-甲氧基小檗碱(1-methoxylberberium chloride,Ⅱ),氯化三乙基苯胺(triethylphcnylamium chloride,Ⅲ)和异紫堇定(isocorydine,Ⅳ)。Ⅱ和Ⅲ系首次从植物中得到。 相似文献
82.
健康人心室复极的昼夜变化研究 总被引:1,自引:1,他引:0
目的 探讨健康人心室复极的昼夜变化规律. 方法 对34例健康体检者的24h动态心电图进行回顾性分析.测定其心率、Q-T间期、QRS波群起点至T波波峰的时间(Q-Tp间期).计算T波波峰至终点的时间(Tp-e时间)、心率校正的Q-T间期(Q-Tc间期)和Tp-e时间(Tp-ec时间)、Tp-e/Q-T值,并比较一天中8个等分时间段的上述参数. 结果 Q-T间期和Tp-e时间呈日间短、凌晨及午夜长的昼夜节律变化,各时间段差异有统计学意义(P<0.01或0.05);Q-T间期与心率呈高度负相关(r=-01796,P<0.01).而Tp-e时间与心率呈低度负相关(r=-01267,P<0.01);各时间段Q-Tc间期接近,而Tp-ec时间呈07:00~09:00最高、10:00~12:00次之、01:00~03:00最低的昼夜节律变化,各时间段差异有统计学意义(P<0.05),Tp-e/Q-T值昼夜变化节律与Tp-ec时间相近.结论 反映心室复极跨壁离散度的Tp-e时间除受心率影响外,尚受昼夜节律的影响. 相似文献
83.
细胞因子在慢性肝衰竭合并全身炎症反应综合征病例中的意义 总被引:1,自引:0,他引:1
目的探讨TNF-α、IFN-γ、LPS、IL-10、IL-12、IL-18在慢性肝衰竭合并全身炎症反应综合征(SIRS)中的意义。方法运用双抗体夹心酶联免疫吸附法检测正常人、一般肝炎患者、慢性肝衰竭组的TNF-α、IFN-γ、LPS、IL-10、IL-12、IL-18。结果自正常对照组到一般肝炎组、慢性肝衰竭非SIRS组、慢性肝衰竭SIRS组,血清中TNF-α、LPS、IL-12及IL-18水平依次升高,IL-10分子水平依次减低,且各组间比较均具有显著性差异。结论TNF-α、LPS、IL-10、IL-12、IL-18水平可以反应出乙型肝炎患者的肝脏损伤程度和疾病严重程度,可能在慢性肝衰竭合并SIRS的发病过程中起到相当重要的作用。 相似文献
84.
汞中毒肾脏损害的早期监测指标筛选 总被引:7,自引:0,他引:7
目的筛选汞作业者肾脏损害的早期监测指标并探讨其临床意义。方法85例汞作业者分为汞接触正常/观察对象组、汞中毒组,并以无汞接触史的65例健康成人作为对照组。分别进行临床体检并测定尿汞(HgU)、血肌酐(B-Cr)、尿肌酐(U-Cr)、血尿素氮(BUN)、尿-N-乙酰-β-D葡萄糖苷酶(NAG)、尿β2-微球蛋白(β2-MG)、尿α1-微球蛋白(α1-MG)和尿视黄醇结合蛋白(RBP),排除肾病史和患有肾脏疾病患者后对结果进行分析。结果汞作业者HgU、B-Cr、NAG、β2-MG、α1-MG和RBP均高于对照组(P<0.01);汞作业正常/观察对象组的β2-MG、NAG和RBP水平高于对照组(P<0.01),α1-MG有升高趋势,但与对照组相比差异无统计学意义,传统肾脏损害指标B-Cr和BUN与对照组相比差异亦无统计学意义。结论长期汞接触可造成肾功能损害,尿NAG、β2-MG、α1-MG、RBP可作为汞作业者肾脏损害的早期监测指标。 相似文献
85.
目的了解各级临床实验室开展HIV血清学筛查试验的情况。方法采用问卷调查方式对141家临床艾滋病检测筛查实验室进行调查,利用Excel表建立数据库并进行分析。结果141家实验室2006年度共检测样本303045份,筛查阳性样本2404份,确认阳性样本276份,筛查阳性检出率和确认符合率分别为0.09%和11.48%。送检样本最多的科室是外、内、急诊和妇儿科。多数实验室采用国产酶联免疫吸附试剂。多数实验室缺少生物安全防护设备。结论进一步加强对实验室的管理,提高检测质量。 相似文献
86.
87.
The optimum marrow ablative regimen for preparing recipients of bone marrow transplantation (BMT) has not been established. gamma- Irradiation, but not busulfan, produces a characteristic microvascular injury pattern which results in depressed capacity of normal lymphocytes to localize into the lymph nodes of syngeneic murine BMT recipients. Since peripheral lymph nodes are important sites for initiation and amplification of immune responses, the preparative regimen might delay recovery of regionally compartmentalized immune functions after BMT. We evaluated the effects of busulfan and gamma- irradiation on the phenotypic and functional reconstitution of helper T- cell function within the peripheral lymph nodes of BMT recipients. Both marrow ablative regimens caused a protracted delay in regeneration of peripheral lymph node CD4+ T cells. Specific helper T-cell functions, such as contact hypersensitivity and alloantigen responses, remained significantly depressed in the lymph nodes of irradiated mice for prolonged periods (up to 60 weeks). These responses recovered more rapidly in busulfan-treated BMT recipients. In contrast, the capacity of peripheral lymph node T cells to provide "help" for antigen-specific immunoglobulin production was only transiently depressed by either preparative regimen. Our experiments confirm the hypothesis that the marrow ablative regimen, particularly gamma-irradiation, may contribute to the period of immunodeficiency which follows BMT. The pattern of immune recovery observed suggests that preparative total body irradiation (TBI) may selectively depress the regional recovery of the TH1 [interleukin-2 (IL-2) and gamma-interferon (gamma-IFN) secreting] lymphocyte subset. 相似文献
88.
Patients who develop inflammatory polyarthritis (IP) after immunization are clinically indistinguishable from other patients with IP 总被引:2,自引:1,他引:2
Harrison BJ; Thomson W; Pepper L; Ollier WE; Chakravarty K; Barrett EM; Silman AJ; Symmons DP 《Rheumatology (Oxford, England)》1997,36(3):366-369
Musculoskeletal symptoms may occur following various types of immunization,
and it has also been suggested that, like infection, immunization may act
as a trigger for rheumatoid arthritis (RA). A total of 48 of 898 (5.3%)
patients with early inflammatory polyarthritis (IP) referred to the Norfolk
Arthritis Register reported an immunization in the 6 weeks prior to symptom
onset. There were no important clinical or demographic differences between
the 48 immunized patients and 185 consecutive patients who did not report
prior immunization. In addition, the frequencies of HLA-DRB1*01. *04 and
the shared epitope in 33 of the immunized patients were similar to those in
the 185 non-immunized patients and to those in 136 healthy controls.
Further results from a case-control study suggest that the rate of
immunization is higher amongst cases (5.5%) than age- and sex-matched
controls (2.8%). In a small number of susceptible individuals, immunization
may thus act as a trigger for RA.
相似文献
89.
Recycling with nicotine patches in smoking cessation 总被引:1,自引:0,他引:1
PHILIP TØNNESEN JESPER NØRREGAARD URBAIN SÄWE KÅRE SIMONSEN 《Addiction (Abingdon, England)》1993,88(4):533-539
The aim was to evaluate if recycling of failures from a smoking cessation study may be of value. The study comprised 126 smokers (50%) of 252 failures, from a double-blind smoking cessation trial with nicotine patch, who accepted recycling after 1 year. Subjects were allocated nicotine patches delivering 15, 20 or 25 mg of nicotine (over 16 hours) according to their base-line saliva cotinine concentrations in an open trial. The treatment period was 12 weeks followed by tapering over 6 weeks. The percentage of quitters after 3, 12, 26, and 52 weeks was 44, 20, 7 and 6%, respectively. After 26 weeks, all subjects had relapsed in the group previously treated with active nicotine patch compared with 12% abstainers in the previous placebo subjects. The sustained abstinence rate without slips after one year was 2%. Recycling does not seem to be of long-term clinical relevance in our set-up for subjects initially treated with nicotine, but of some value in subjects quitting without nicotine therapy initially. 相似文献
90.