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1.
With global warming forecast to continue into the foreseeable future, heat waves are very likely to increase in both frequency and intensity. In urban regions, these future heat waves will be exacerbated by the urban heat island effect, and will have the potential to negatively influence the health and welfare of urban residents. In order to investigate the health effects of the urban heat island (UHI) in Shanghai, China, 30 years of meteorological records (1975–2004) were examined for 11 first- and second-order weather stations in and around Shanghai. Additionally, automatic weather observation data recorded in recent years as well as daily all-cause summer mortality counts in 11 urban, suburban, and exurban regions (1998–2004) in Shanghai have been used. The results show that different sites (city center or surroundings) have experienced different degrees of warming as a result of increasing urbanization. In turn, this has resulted in a more extensive urban heat island effect, causing additional hot days and heat waves in urban regions compared to rural locales. An examination of summer mortality rates in and around Shanghai yields heightened heat-related mortality in urban regions, and we conclude that the UHI is directly responsible, acting to worsen the adverse health effects from exposure to extreme thermal conditions.  相似文献   
2.
Dayaoshania cotinifolia W.T. Wang is a critically endangered perennial herb endemic to southern China. Simple sequence repeat (SSR) markers were employed to assess genetic diversity in two populations of D. cotinifolia. Eight primer pairs generated a total of 36 alleles, with a mean of 4.5 alleles per locus. The expected heterozygosity (He = 0.416) and observed heterozygosity (Ho = 0.508) indicated a moderate level of genetic diversity, though the genetic differentiation between the populations was low (Fst = 0.014), a result that was supported by a higher gene flow (Nm = 18.000). No severe bottleneck effect was detected in the two populations. Thus, the endangered status of this species is most likely due to anthropologic effects rather than a lack of genetic diversity. In situ conservation strategies should be promoted, and the sizes of the populations should be increased through artificial breeding.  相似文献   
3.
银杉花粉生命力及其变异   总被引:3,自引:0,他引:3       下载免费PDF全文
中国特有植物银杉(Cathay argyrophylla)是最濒危的松杉类植物之一。研究表明,受精前胚珠的高败育率是银杉生殖效率低的重要原因之一,但迄今对银杉花粉活力及其变异仍不得而知。由于花粉活力对授粉、受精、种子产量和质量以及后代适合度都有直接影响,该研究采用TTC染色和体外萌发法测定了来自大瑶山(Dayaoshan, DYS)和花坪(Huaping, HP)两个地区7个种群16个个体52份银杉花粉样品的生活力。结果表明银杉花粉的活力水平(93.3%)与其它裸子植物相当,干燥低温条件下银杉的花粉活力比较稳定,体外萌发的适宜蔗糖浓度在13%左右。ANOVA分析揭示种群内个体间的花粉活力差异不大(p>0.05),而地区内的种群间及地区间的花粉活力有显著差异(p<0.05)。银杉花粉活力与其生殖成功没有相关性。在上述基础上,从控制授粉的角度讨论了银杉的保护策略和复壮的可能性。  相似文献   
4.
目的观察硬膜外与腰硬联合麻醉两种模式在分娩镇痛中的不良反应。方法选择单胎足月初产妇100例,随机分为硬膜外分娩镇痛组(E组)50例,腰硬联合镇痛组(S组)50例。观察两组产妇运动神经阻滞、皮肤瘙痒、恶心呕吐不良反应的发生情况。结果 S组产妇皮肤瘙痒发生率明显高于E组(P0.05),但均为轻度,S组恶心呕吐发生率高于E组(P0.05)。结论蛛网膜下腔使用舒芬太尼联合硬膜外腔镇痛模式可以快速、有效进行镇痛,但是瘙痒和恶心呕吐的副作用发生率较高。  相似文献   
5.
Heat wave impacts on mortality in Shanghai, 1998 and 2003   总被引:2,自引:0,他引:2  
A variety of research has linked extreme heat to heightened levels of daily mortality and, not surprisingly, heat waves both in 1998 and in 2003 all led to elevated mortality in Shanghai, China. While the heat waves in the two years were similar in meteorological character, elevated mortality was much more pronounced during the 1998 event, but it remains unclear why the human response was so varied. In order to explain the differences in human mortality between the two years’ heat waves, and to better understand how heat impacts human health, we examine a wide range of meteorological, pollution, and social variables in Shanghai during the summers (15 June to 15 September) of 1998 and 2003. Thus, the goal of this study is to determine what was responsible for the varying human health response during the two heat events. A multivariate analysis is used to investigate the relationships between mortality and heat wave intensity, duration, and timing within the summer season, along with levels of air pollution. It was found that for heat waves in both summers, mortality was strongly associated with the duration of the heat wave. In addition, while slightly higher than average, the air pollution levels for the two heat waves were similar and cannot fully explain the observed differences in human mortality. Finally, since the meteorological conditions and pollution levels for the two heat waves were alike, we conclude that improvements in living conditions in Shanghai, such as increased use of air conditioning, larger living areas, and increased urban green space, along with higher levels of heat awareness and the implementation of a heat warning system, were responsible for the lower levels of human mortality in 2003 compared to 1998.  相似文献   
6.
Material of the paederine genera Domene Fauvel, 1873 and Lathrobium Gravenhorst, 1802 from the Dayao Mountains, southern China, is examined. Eight species are identified, three of them described previously and five undescribed. Four species are described and illustrated for the first time: Domene hei Peng & Li, sp. n., Lathrobium jinxiuense Peng & Li, sp. n., Lathrobium kuan Peng & Li, sp. n. and Lathrobium leii Peng & Li, sp. n. One probably undescribed species of Lathrobium remains unnamed.  相似文献   
7.
《Bioresource technology》2000,71(2):103-112
Granular activated carbons (GACs) were produced from sugarcane bagasse combined with one of two binders (corn syrup, coal tar) by physical activation and from pecan shells by physical and chemical activation. GACs were evaluated for their physical (hardness, bulk density), chemical (ash, pH), surface (surface area, pore size distribution, surface chemistry), and adsorption properties (molasses color removal, sugar decolorization) and compared with two commercial reference carbons. Results showed that larger surface area, a well-developed macro- and mesoporosity, and a minimal surface charge were desirable in GACs designed for sugar decolorization. Steam activation of pecan shells carbon was the only by-product-activation combination that produced GAC with all the above three desirable characteristics of a good sugar decolorizer. Chemical activation of pecan shells yielded GACs with high surface area and adequate pore size distribution but with large surface charge. In contrast, sugarcane bagasse-based GACs exhibited low surface areas and unsatisfactory physical/chemical properties.  相似文献   
8.
We aimed to examine the nucleoside triphosphate diphosphohydrolases (NTPDase) in lymphocytes; adenosine deaminase (ADA) and butyrylcholinesterase (BChE) in serum; and acetylcholinesterase (AChE), superoxide dismutase (SOD), and catalase (CAT) activity in whole blood; since these enzymes are involved in inflammation responses as well as in oxidative stress conditions. We also checked the levels of total thiols (T-SH), non-protein thiols (NPSH), and thiobarbituric acid reactive substances (TBARS) in serum of patients with lung cancer. We collected blood samples from patients (n = 31) previously treated for lung cancer with chemotherapy. Patients were classified as stage IIIb and IV according to the Union for International Cancer Control (UICC). The results showed a significant increase in the hydrolysis of ATP, ADP, and adenosine in patients when compared with the control group. The activity of AChE, SOD, and CAT as well as the T-SH and NPSH levels were higher in patients group and TBARS levels were lower in patients compared with the control group. These findings demonstrated that the enzymes activity involved in the control of inflammatory and immune processes as well as the oxidative stress parameters are altered in patients with lung cancer.  相似文献   
9.
10.
建立尿素梯度凝胶过滤复性重组人脱氧核糖核酸酶Ⅰ的方法。将诱导表达的重组人脱氧核糖核酸酶Ⅰ包涵体通过初步纯化后变性,然后在尿素梯度凝胶过滤色谱柱Sephadex G-75中复性,洗脱流速0.4 mL/min,复性完毕后透析除去小分子复性剂,使用琼脂糖电泳法检验其有活性后,再用单向酶扩散法测定其酶活力为655.8 U/mg,复性得率为83.7%。最后通过LC-ESI-MS/MS从氨基酸序列组成上证明复性产物是重组人脱氧核糖核酸酶Ⅰ。结果表明,建立的方法能成功用于复性变性的重组人脱氧核糖核酸酶Ⅰ包涵体蛋白,获得了可用于结构和功能研究的具有生物学活性的重组人脱氧核糖核酸酶Ⅰ。  相似文献   
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