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51.
To explore the role of nitric oxide (NO) and oxidative stress in the pathogenesis of adhesion formation and in endometriosis-associated infertility, we examined the peritoneal total antioxidant status (TAS) and the concentrations of products of NO metabolism in women with endometriosis (early stage, n = 12; advanced stage, n = 12) and in fertile women without endometriosis (n = 10). Peritoneal CA 125 and oestrogen and progesterone concentrations were also measured to examine their contributions to TAS and the production of NO. We failed to demonstrate any significant difference in TAS and in the products of NO metabolism in peritoneal fluids among women with early and advanced stages of endometriosis compared with fertile women without endometriosis during the early follicular phase. TAS and the concentration of the products of NO metabolism were not related to concentrations of CA 125, oestrogen or progesterone. The concentration of CA 125 in serum, but not in peritoneal fluid, was positively correlated with the severity of endometriosis. The volume of peritoneal fluid and the progesterone concentration were significantly increased in the group with advanced endometriosis. TAS and the concentration of the products of NO metabolism did not increase in peritoneal fluids from women with endometriosis during the early follicular phase. Their role in the pathophysiology of endometriosis needs to be explored further.   相似文献   
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广东省艾滋病病毒职业性暴露应急系统响应情况分析   总被引:3,自引:0,他引:3  
目的建立艾滋病病毒(HIV)职业性暴露应急系统,分析应急响应情况。方法回顾性收集和分析2002~2004年报告的广东省各地HIV职业性暴露个案。结果2002~2004年共报告152例HIV职业性暴露个案,其中医务人员占74.34%,干警占13.82%。29.61%是皮肤黏膜接触性暴露,70.39%是创伤性暴露。暴露级别中,一级暴露占57.24%,二级暴露占35.53%,三级暴露占7.24%。94.74%的暴露者进行了暴露后应急局部处理。发生暴露后,只有38.16%的暴露者采用了合理的处理方案。104例(68.42%)进行了预防性服药,但其中仅有27.88%(29/104)的人采用合理的服药方案。48例(31.58%)未进行预防性服药,但其中仅有60.42%(29/48)的人是真正无需预防性服药者。92例暴露者经12个月的随访未发现有感染HIV者。结论广东省HIV职业性暴露应急系统能有效地响应全省HIV职业性暴露事件,但仍需加强对职业性暴露后应急处理技术的知识培训。  相似文献   
54.
广州地区大学生对转基因食品的认知与态度   总被引:2,自引:0,他引:2  
目的了解大学生对转基因食品的认知与态度,为大学生的食品健康教育提供科学依据。方法采用分层整群抽样的方法,对广州市1 010名大学生进行问卷调查。结果64.0%的大学生对转基因食品有不同程度的了解;40.1%的学生认为转基因食品营养价值更高;39.9%的学生认为转基因食品有预防疾病、提高免疫力等作用;34.0%的学生认为转基因食品中含有的细菌与病毒等基因会对人体有害;63.5%的学生赞成在中国推出转基因食品,并希望加快发展速度;75.7%的学生认为应制定完善的管理法规,并给转基因食品贴上明确的标签。结论大学生对转基因食品缺乏认知,应加强对大学生转基因食品知识的教育。  相似文献   
55.
槐定碱的气相色谱测定法及其在兔体内的药代动力学   总被引:7,自引:0,他引:7  
兔血浆中槐定碱的气相色谱测定条件:氮气、氢气和空气的流速分别为60,40和380ml/min。填充柱、进样室和检测室温度分别为190,280和300℃。内标物为槐胺碱,血浆中槐定碱浓度为3.0和10.0μg/ml时,测得回收率分别为103.6±2.4%(CV=2.34%)和101.5±6.5%(CV=6.35%)。线性范围为1~15/μg/ml。槐定碱在兔体内的药代动力学按二房室拟合,其混合参数值:α.0.0864 min-1;β.0.00932 min-1;Vc.1.19 L/kg;Varea.2.07 L/kg;Vdvv.1.99L/kg;Cl.19.3 ml/min·kg;MRT.103min。  相似文献   
56.
紫外分光光度法测定平阳霉素霜的含量   总被引:2,自引:0,他引:2  
目的:用紫外分光光度法测定平阳霉素霜的含量,为该药提供质量控制方法。方法:紫外分光光度法。结果:平阳霉素甲醇液在293.5nm处有最大吸收,在30-70μg/ml范围内吸收度与浓度有良好线性关系,其回归方程为A=0.01066C-0.008(r=0.9998),平均回收率(n=5)为100.05%,RSD=0.98%。结论:该法作为平阳霉素霜剂的含量测定方法、快捷准确、简便易行,适用于医院快检。  相似文献   
57.
Background  Recent studies suggest a role for the endocannabinoid system, including fatty acid amide hydrolase (FAAH), in intestinal inflammation.
Aim  To analyse FAAH expression and the FAAH 385 C/A (p.Pro129Thr; rs324420) single nucleotide polymorphism (SNP) in-patients with Crohn's disease (CD) and ulcerative colitis (UC).
Patients and methods  Genomic DNA from 1008 individuals (CD: n  = 435; UC: n  = 167; controls: n  = 406) was analysed for the FAAH 385 C/A SNP. We determined FAAH mRNA expression by quantitative PCR in CD and UC lesions as well as in intestinal epithelial cells (IECs).
Results  There were no significant differences regarding the frequency of this SNP in the three study groups (CD, UC, controls). However, CD patients homozygous for the FAAH p.Pro129Thr polymorphism were more likely to develop a severe disease phenotype associated with fistulas ( P  = 0.03, OR 3.12, 95% CI 1.08–8.98) and extra-intestinal manifestations ( P  = 0.005, OR 4.29, CI 1.49–12.35). In UC, homozygous carriers had an earlier disease onset than wild-type carriers ( P  = 0.01). FAAH mRNA expression correlated with IL-8 mRNA expression in CD lesions ( r  = 0.53). However, pro-inflammatory stimuli did not significantly increase FAAH mRNA expression in IECs.
Conclusion  The FAAH p.Pro129Thr polymorphism may modulate the CD phenotype.  相似文献   
58.
The divergence of the hemagglutinin gene of A/goose/Guangdong/1/1996‐lineage H5N1 viruses during 2011 and 2012 (807 new sequences collected through December 31, 2012) was analyzed by phylogenetic and p‐distance methods to define new clades using the pre‐established nomenclature system. Eight new clade designations were recommended based on division of clade 1·1 (Mekong River Delta), 2·1·3·2 (Indonesia), 2·2·2 (India/Bangladesh), 2·2·1·1 (Egypt/Israel), and 2·3·2·1 (Asia). A simplification to the previously defined criteria, which adds a letter rather than number to the right‐most digit of fifth‐order clades, was proposed to facilitate this and future updates.  相似文献   
59.
Please cite this paper as: WHO/OIE/FAO. (2012) Continued evolution of highly pathogenic avian influenza A(H5N1): Updated nomenclature. Influenza and Other Respiratory Viruses 6(1), 1–5. Background Continued evolution of highly pathogenic avian influenza A (H5N1) throughout many regions of the eastern hemisphere has led to the emergence of new phylogenetic groups. A total of 1637 new H5N1 hemagglutinin (HA) sequences have become available since the previous nomenclature recommendations described in 2009 by the WHO/OIE/FAO H5N1 Evolution Working Group. A comprehensive analysis including all the new data is needed to update HA clade nomenclature. Methods Phylogenetic trees were constructed from data sets of all available H5N1 HA sequences. New clades were designated on the basis of phylogeny and p‐distance using the pre‐established nomenclature system (Emerg Infec Dis 2008; 14:e1). Each circulating H5N1 clade was subjected to further phylogenetic analysis and nucleotide sequence divergence calculations. Results All recently circulating clades (clade 1 in the Mekong River Delta, 2.1.3 in Indonesia, 2.2 in India/Bangladesh, 2.2.1 in Egypt, 2.3.2, 2.3.4 and 7 in Asia) required assignment of divergent HA genes to new second‐, third‐, and/or fourth‐order clades. At the same time, clades 0, 3, 4, 5, 6, 8, 9, and several second‐ and third‐order groups from clade 2 have not been detected since 2008 or earlier. Conclusions New designations are recommended for 12 HA clades, named according to previously defined criteria. In addition, viruses from 13 clades have not been detected since 2008 or earlier. The periodic updating of this dynamic classification system allows continued use of a unified nomenclature in all H5N1 studies.  相似文献   
60.
Increased ribonucleotide reductase (RR) activity has been linked with malignant transformation and tumor cell growth. Therefore, this enzyme is considered to be an excellent target for cancer chemotherapy. We have examined the effects of a newly patented RR inhibitor, trimidox (3,4,5-trihydroxybenzohydroxamidoxime). Trimidox inhibited the growth of human promyelocytic leukemia HL-60 cells with an IC50 of 35 mumol/L. Incubation of HL-60 cells with 50 mumol/L trimidox for 24 hours decreased deoxyguanosine triphosphate (dGTP) and deoxycytidine triphosphate (dCTP) pools to 24% and 39% of control values, respectively. Incubation of HL-60 cells with 20 to 80 mumol/L trimidox even up to a period of 4 days did not alter the distribution of cells in different phases of cell cycle. Sequential incubation of HL-60 cells with trimidox (25 mumol/L) for 24 hours and then with 10 mumol/L tiazofurin (an inhibitor of inosine monophosphate dehydrogenase) for 4 days produced synergistic growth inhibitory activity, and the cell number decreased to 16% of untreated controls. When differentiation- linked cell surface marker expressions were determined in cells treated with trimidox and tiazofurin, a significantly increased fluorescence intensity was observed for the CD 11b (2.9-fold). CD 33 (1.9-fold), and HLA-D cell surface antigens. Expression of the transferrin receptor (CD71) increased 7.3-fold in cells treated with both agents, compared with untreated controls. Our results suggest that trimidox in combination with tiazofurin might be useful in the treatment of leukemia.  相似文献   
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