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991.
目的了解泰州市游泳池水质的卫生状况,预防介水传染病的传播,保障游泳人群身体健康。方法2010-2013年的6-8月份对泰州市游泳池水进行抽样,按GB/T 17220-1998对水样进行采集,按GB/T 18204-2000、GB/T 5750-2006对水样进行检验,按GB/T 9667-1996对水样进行评价。结果共检测游泳池水样93份,合格35份,总合格率为37.6%。不合格项目主要为游离性余氯,其次为尿素、细菌总数、大肠菌群、p H值;宾馆游泳池水的合格率高于公共游泳池;常规菌合格率与游离性余氯浓度密切相关。结论泰州市游泳池水质存在一定的安全隐患,卫生行政部门应加强监管力度,督促业主做好水质管理工作。  相似文献   
992.
HPLC-ICP-MS测定硒蛋白中硒代氨基酸的方法   总被引:2,自引:0,他引:2  
目的建立一种适用于检测硒蛋白中硒代氨基酸的有效方法。方法硒蛋白样品采用酸脱蛋白质的方法,在酸性条件下使蛋白质变性沉淀,取沉淀物运用蛋白酶K、胰蛋白酶、链蛋白酶酶解硒蛋白样品;在5 mmol/L的柠檬酸铵中加2%的甲醇溶液作为流动相,并用柠檬酸或氨水精确调节流动相的p H值(p H=4.9),用离子交换柱分离硒代半胱氨酸(Se Cys)、硒代蛋氨酸(Se Met)等硒代氨基酸,通过ICP-MS检测其含量,并运用方法学验证实验结果。结果所建立的硒蛋白中硒代氨基酸检测方法,检出限分别为3.5μg/kg、11.2μg/kg,线性范围(以Se计)为0μg/L~200μg/L,加标回收率为75%~120%。结论经实验证明,该检测方法适用于食品营养强化剂硒蛋白中硒代氨基酸的分析,此方法的建立对食品的成分分析和食品的开发利用具有重要意义。  相似文献   
993.
钙化性主动脉瓣疾病是常见的心血管疾病,随着人口老龄化的日益加剧其逐渐成为主要的医疗负担。瓣膜置换术是该病的主要治疗方法,但高龄群体手术风险较大,并发症发生率高。且目前仍缺少预防或减缓疾病进展的有效药物。研究发现,脂蛋白(a)在瓣膜钙化的病理过程中起关键作用,脂蛋白(a)水平升高是钙化性主动脉瓣疾病的重要危险因素,显著增加主动脉瓣狭窄的患病风险。本文综述了脂蛋白(a)在钙化性主动脉瓣疾病的病理机制中的作用及其与治疗方面的相关性。  相似文献   
994.
肠道菌群在人类健康和疾病中的作用逐渐被人们重视.目前已有一些关于肠道菌群与胰腺炎关系的研究报道,这些报道揭示了肠道菌群在胰腺炎发生发展过程中发挥着某些重要作用.目前还不清楚这些具体作用机制,但肠道菌群失调被认为促进胰腺炎症变化的假说已经有了初步的共识.本文概述了肠道菌群与胰腺炎的相关性,旨在为今后的进一步研究提供某些参考和思路.  相似文献   
995.
AIM: To clone, identify and study new NS5ATP2 gene and its spliced variant transactivated by hepatitis C virus non-structural protein 5A. METHODS: On the basis of subtractive cDNA library of genes transactivated by NS5A protein of hepatitis C virus, the coding sequence of new gene and its spliced variant were obtained by bioinformatics method. Polymerase chain reaction (PCR) was conducted to amplify NS5ATP2 gene. RESULTS: The coding sequence of a new gene and its spliced variant were cloned and identified successfully. CONCLUSION: A new gene has been recognized as the new target transactivated by HCV NS5A protein. These results brought some new clues for studying the biological functions of new genes and pathogenesis of the viral proteins.  相似文献   
996.
Objective To detect the expression of type Ⅰ interferon in monocyte-derived dendritic cells(MoDCs)after Toll like receptor(TLR)3 triggered in patients with chronic hepatitis B(CHB),and to evaluate immune responses of CHB patients and its roles in the mechanisms of persistent infection of hepatitis B virus(HBV)and chronicity of hepatitis.Methods Peripheral blood mononuclear cells(PBMCs)were isolated and purified using magnetic beads(plasma was saved simultaneously)from 26 CHB patients and 18 healthy volunteers(HV).Dendritic cells(DCs)were induced and proliferated in a culture medium with recombinant human granulocyte macrophage colony stimulating factor(rhGM-CSF)and recombinant human interleukin(rhIL-4).EX3s were stimulated with Poly Ⅰ:C and the supernatants were collected at 0 h and 24 h after stimulation.Type Ⅰ interferon(IFN-α and IFN-β)in plasma and supernatants were examined by enzyme linked immunosorbent assay (ELISA).Results The levels of type Ⅰ interferon in plasma were not significantly different in groups of HV and CH B.IFN-α and IFN-β expressions in supernatants before Poly Ⅰ:C stimulation were(80.00±16.15)ng/L,(36.39±13.90)ng/L in CHB group and(76.76±15.90)ng/L,(37.14±13.68)ng/L in HV group,respectively.And there were no statistical differences between two groups(t=1.651,t=0.178;both P>0.05).IFN-α expressions in supernatants at 24 h after stimulation in two groups were both higher than those before stimulation(at 0 h),but there were no statistical differences(t=1.534,t=1.243;both P>0.05).IFN-β expressions in supernatants at 24 h after stimulation in HV group was(54.57±16.80)ng/L,which was significantly higher than that at 0 h(37.14±13.68)ng/L(t=4.061,P<0.05).However,there was no significant difference at 24 h than tht at 0 h in CHB group(t=1.796,P>0.05).At 24 h after stimulation.IFN-β level was(54.57±16.80)ng/L in HV group,which was significantly higher than that[(41.64±12.57)ng/L]in CHB group(t=2.921,P<0.05).Conclusions Functions of MoDCs from CHB patients are impaired and MoDCs could not express type Ⅰ interferon normally.Expression of type Ⅰ interferon after TLR3 triggered in CHB patients is mainly IFN-β.  相似文献   
997.
OBJECTIVE: This research was designed to explore the role of joint and nonarticular clinical manifestations traditionally evaluated in Chinese herbal medicine in predicting efficacy of treatment for rheumatoid arthritis. METHODS: Three hundred ninety-six patients were randomly divided to receive Western medicine (WM) therapy, 197 cases; and traditional Chinese herbal medicine (TCM), 199 cases. A complete physical examination and 18 clinical manifestations typically assessed in TCM were recorded before the randomization. The WM therapy included diclofenac extended action tablets, methotrexate, and sulfasalazine. The TCM therapy included Glucosidorum Tripterygll Totorum tablets and Yishen Juanbi tablets. The American College of Rheumatology (ACR) response criteria were used for efficacy evaluation. All data were analyzed using the SPSS11.5 statistical package. RESULTS: ACR20 and 50 responses with WM treatment were higher at 24 weeks than in the TCM group. In the WM group, 89% achieved ACR20 whereas 65.8% on TCM reached this response In the WM group, efficacy was negatively related to subjective symptoms of dizziness, and positively related to joint tenderness and thirst as recorded at entry. In contrast, in the TCM group the efficacy was positively related to joint tenderness and joint pain, and negatively related to the joint stiffness and more nocturia. CONCLUSION: Symptoms including those not directly related to joints and those inquired about in TCM may have influence on the efficacy of therapy, and might merit further study to ascertain if they can be helpful to guide specific therapy.  相似文献   
998.
Marker-specific sorting of rare cells using dielectrophoresis   总被引:1,自引:0,他引:1       下载免费PDF全文
Current techniques in high-speed cell sorting are limited by the inherent coupling among three competing parameters of performance: throughput, purity, and rare cell recovery. Microfluidics provides an alternate strategy to decouple these parameters through the use of arrayed devices that operate in parallel. To efficiently isolate rare cells from complex mixtures, an electrokinetic sorting methodology was developed that exploits dielectrophoresis (DEP) in microfluidic channels. In this approach, the dielectrophoretic amplitude response of rare target cells is modulated by labeling cells with particles that differ in polarization response. Cell mixtures were interrogated in the DEP-activated cell sorter in a continuous-flow manner, wherein the electric fields were engineered to achieve efficient separation between the dielectrophoretically labeled and unlabeled cells. To demonstrate the efficiency of marker-specific cell separation, DEP-activated cell sorting (DACS) was applied for affinity-based enrichment of rare bacteria expressing a specific surface marker from an excess of nontarget bacteria that do not express this marker. Rare target cells were enriched by >200-fold in a single round of sorting at a single-channel throughput of 10,000 cells per second. DACS offers the potential for automated, surface marker-specific cell sorting in a disposable format that is capable of simultaneously achieving high throughput, purity, and rare cell recovery.  相似文献   
999.
目的 了解全国改水降氟措施防治饮水型地方性氟中毒的效果,探索控制饮水型氟中毒改水干预措施效果的综合评价方法。方法 制定纳入标准、剔除标准,制定检索策略;通过检索,共查找相关文献450篇,其中符合Meta分析要求的有效文献54篇。采用Cochrane协作网提供的Revman4.2.3统计软件对入选文献进行Meta分析。结果 改水11~20年,儿童氟斑牙患病率从69.3%降到23.8%,成人氟骨症患病率下降了4.9%,儿童尿氟由5.31mg/L降到1.50mg/L。改水21~31年,儿童氟斑牙患病率从78.6%降到23.9%,成人氟骨症患病率下降19.2%。平均改水13年,水含氟量由改水前的4.85mg/L降到0.60mg/L。改水后经济效益明显增加,血生化指标明显降低。结论改水降氟是防治饮水型氟中毒的有效措施,只要饮水含氟量降到允许标准以下,儿童氟斑牙患病率、成人氟骨症患病率和儿童尿含氟量都会明显降低。经济效益的增加间接反映了改水降氟的效果。Meta分析为从整体水平揭示全国改水降氟预防饮水型地方性氟中毒的效果提供了新的研究方法和手段,将对饮水型氟中毒防控干预措施效果综合评价研究起到积极的推动作用。  相似文献   
1000.
调查了4950例晚血,709例(14.3%)发生过上消化道出血。已切脾者有出血史的532例中,术前出血338例,268例(79.3%)术后未再出血,术后复发出血70例(20.7%)。切脾前无出血史者2781例,术后发生出血的194例(7%)。提示单纯脾切除对防治上消化道出血有一定效果,但术前有出血,术后再出血的发生率较术前无出血者高。对近年有出血史的50例晚血作了纤维胃镜检查,74%的患者伴有胃十二指肠病变.并对晚血患者上消化道出血的防治方法进行了探讨。  相似文献   
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