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1.
Understanding why persons with human immunodeficiency virus (HIV) have accelerated atherosclerosis and its sequelae, including coronary artery disease (CAD) and myocardial infarction, is necessary to provide appropriate care to a large and aging population with HIV. In this review, we delineate the diverse pathophysiologies underlying HIV-associated CAD and discuss how these are implicated in the clinical manifestations of CAD among persons with HIV. Several factors contribute to HIV-associated CAD, with chronic inflammation and immune activation likely representing the primary drivers. Increased monocyte activation, inflammation, and hyperlipidemia present in chronic HIV infection also mirror the pathophysiology of plaque rupture. Furthermore, mechanisms central to plaque erosion, such as activation of toll-like receptor 2 and formation of neutrophil extracellular traps, are also abundant in HIV. In addition to inflammation and immune activation in general, persons with HIV have a higher prevalence than uninfected persons of traditional cardiovascular risk factors, including dyslipidemia, hypertension, insulin resistance, and tobacco use. Antiretroviral therapies, although clearly necessary for HIV treatment and survival, have had varied effects on CAD, but newer generation regimens have reduced cardiovascular toxicities. From a clinical standpoint, this mix of risk factors is implicated in earlier CAD among persons with HIV than uninfected persons; whether the distribution and underlying plaque content of CAD for persons with HIV differs considerably from uninfected persons has not been definitively studied. Furthermore, the role of cardiovascular risk estimators in HIV remains unclear, as does the role of traditional and emerging therapies; no trials of CAD therapies powered to detect clinical events have been completed among persons with HIV. 相似文献
2.
巢湖水藻类毒性及对饮用水水质影响 总被引:8,自引:0,他引:8
目的了解巢湖含藻水源水和藻类毒性对饮用水水质的影响。方法于1999年在距巢湖水厂岸边1.5km(A点:废弃水源)和3.0km(B点:现用水源)处取水样进行巢湖的浮游藻类调查,取B点湖水及其处理后的饮用水检测微囊藻毒素(MC)含量,并进行水质分析及Ames试验、微核试验和单细胞凝胶电泳(SCGE)试验。结果A和B点水样全年共检出浮游藻类83种,分属于8门49属,年均藻量(每升水样藻细胞数)B点(8205.67×104个/L)比A点(7024.24×104个/L)高16.8%。巢湖16份水样中有12份检出了MC,2份超标;合肥和巢湖市5个水厂原水及饮用水中未检出MC(不含四水厂)。合肥四水厂MC含量较低的原水,经过运输贮存后,清水池一次出厂水MC含量超标,经混凝、加氯和活性炭等处理后,二次出厂水未检出MC;原水中总氮等6项指标不同程度地超过GB3838-2002地表水环境质量标准Ⅴ类标准,经处理后的饮用水符合卫生标准;Ames试验与微核试验提示原水有可疑致突变性,经混凝处理不能消除,加氯后致突变性仍存在。SCGE试验表明原水有机浓集物存在DNA损伤效应。结论现用巢湖水源浮游藻类的污染重于废弃水源,湖水与四水厂清水池一次出厂水中的MC均存在超标现象,原水和饮用水存在可疑致突变性。 相似文献
3.
洞庭湖区血吸虫病化疗效果观察点的纵向研究 总被引:2,自引:0,他引:2
在洞庭湖血吸虫病严重流行区,1987年以来采用大范围人畜化疗,到化疗第三年本地居民血吸虫病平均感染率从17.2%下降到6.5%,下降率为62.2%;到化疗第七年,在第三年的基础上继续下降32.3%,居民平均感染率为4.4%。其中以洪道区15个观察点疫情较轻,从化疗第三年起居民血吸虫病平均感染率即可稳定在5%以下。 相似文献
4.
Wai Mun Huang 《Virology》1975,66(2):508-521
During the prereplicative period after the infection of Escherichia coli by phage T4, more than 50 proteins are synthesized. Many of them have been identified with their corresponding genes. Among them, at least 13 are selectively enriched in the membrane preparation. They include the products of the two rII genes, genes 39, 52 (DNA-delay), and others not yet identified. The majority of these proteins (90%) are extractable by the detergent, sarkosyl, and are possibly associated with the inner or cytoplasmic membrane. Based on their electrophoretic migration in SDS-polyacrylamide gels and on their tryptic fingerprints, these proteins are found to be phage induced. Two of the newly synthesized proteins that are selectively enriched in the cell wall or outer envelope fraction are found to be identical with two envelope proteins of the host cell. They are continually synthesized after phage infection although general host protein synthesis is shut off. 相似文献
5.
Gordon K. Livingston Lisa A. Cannon D. Timothy Bishop Penny Johnson Robert M. Fineman 《Cancer Genetics and Cytogenetics》1983,9(3):289-299
Variation in sister chromatid exchange (SCE) frequency in lymphocytes of 125 persons was compared using a multivariate general linear model. The study was performed to determine whether SCE frequency differs with respect to age, sex, smoking, and breast cancer status. Study subjects were divided into: members of two branches of families having an excess of cancer (primarily breast) including a brother and sister in one family who developed nonbreast malignancies within 1 yr of the study; women in both families successfully treated for breast cancer (all at least 5 yr posttreatment); and women from the general population with confirmed breast cancer.Controls consisted of spouses who married into the high-risk kindreds, hospital personnel, and others (primarily tradesmen without history of occupational exposure). Results show that: (1) Women with active breast cancer have a significantly higher mean SCE frequency than control women or women greater than 5 yr posttreatment for breast cancer; (2) Cigarette smokers show a significantly higher number of SCEs than was observed in nonsmokers; (3) The increase in SCE level in smokers is dose-related to exposure as measured by cumulative pack-years; (4) SCE values in both high-risk families are not significantly different from controls; (5) Neither the age nor sex of the individual affects SCE frequency; and (6) The observed distribution of exchanges agrees with that expected based on the proportion of the genome represented by each chromosome group. 相似文献
6.
7.
Neuronal types contributing to the inner plexiform layer of the cat retina are described based primarily on light microscopy of Golgi-impregnated retinal whole-mounts. Cells have been characterized on morphological criteria that include dendritic branching patterns, dendritic tree sizes, cell body sizes and stratification of processes in the inner plexiform layer. Nine different types of bipolar cell, 22 different types of amacrine cell and 23 different types of ganglion cell can be distinguished using one or more of these morphological criteria. The significance of the different morphological types of cells is discussed, particularly in relationship to the functional bisublamination of the cat inner plexiform layer. 相似文献
8.
Identification and Determination of Microcystins in Source Water an Waterbloom Sample From Meiliang Bay, Taihu Lake, China 总被引:1,自引:0,他引:1
OBJECTIVE: To identify and determine the congener and level of microcystins in the source water of Taihu Lake. METHODS: Improved method of SPE combined with HPLC was employed to detect the concentration and varieties of microcystins in source water and bloom samples collected from Meiliang Bay, Taihu Lake. RESULTS: The contents of two predominant microcystin components, MC-RR, and MC-LR, were relatively high in samples during warm months and correlated with the phase of algae growth. The maximum concentrations of MC-RR and MC-LR in water sample reached 3.09 +/- 0.53 microg/L and 2.39 +/- 0.41 microg/L during the period of water bloom in September 2004, respectively. Even without waterbloom, the concentration of MC-LR in source water sample was still higher than the guideline value. CONCLUSION: The status of microcystin pollution in this region is serious and measures to monitor and control the growth of cyanobacteria are urgently needed. 相似文献
9.
目的了解微山湖区生活饮用水水质情况。方法2005年对微山湖区生活饮用水选择监测点采样检测。结果在微山湖区84处监测点采集和检测水样168份,合格率为31.55%,深井水、浅井水、地面水合格率分别为41.67%、36.84%、11.36%。结论微生物污染是存在的主要卫生问题,防止湖区污染,加强水污染治理是今后工作中的新课题。 相似文献
10.
目的在南水北调条件下,观察人工北移至非适宜地区山东省东平湖区湖北钉螺生存繁殖的能力。方法近年,在东平湖区的湖心岛以螺笼放养钉螺,定量观察其生存繁殖情况。结果亲代钉螺可以在东平湖越冬生存,存活率为60.51%(118/195);经过2个冬季24个月放养,繁殖产生了子2代钉螺228只,其螺口数量较亲代钉螺数量增长了14.00%;经过3个冬季36个月放养,钉螺繁殖产生了子3代钉螺86只,其数量较亲代钉螺减少了57.00%,与子2代钉螺数量比较减少了62.28%;经过4个冬季48个月放养,钉螺存活率为0。结论南水北调东线南端长江取水口地区的湖北钉螺在血吸虫病非流行区山东省东平湖区可以繁殖到子3代,生存繁殖的时间不超过4个冬季、48个月,呈现逐年消亡趋势。报道了在中国大陆北纬35 055/地区,人工北移到此地的钉螺在湖滩铁丝笼内放养状态下生存繁殖的纵向观察结果。 相似文献