Diurnal Changes in the Sugar and Organic Anion Concentrations in Red Beet Leaves

Marked diurnal fluctuations in the concentrations of ethanolsoluble sugars and organic anions occurred in red beet leaves.These fluctuations were related to solar radiation and air temperature.Leaves from four plots which had received different manurialtreatments contained significantly different mean sugar andanion concentrations, but the patterns of the diurnal fluctuationswere not affected by the manurial treatments. The results indicated a daily production of photosynthate equalto about 19 per cent per day (leaf-weight basis), compared tothe net assimilation rate of 17 per cent per day as estimatedfor similar plants from dry-weight increase. From the results no evidence can be adduced to support the hypothesisthat sugar accumulated in the leaves to an extent which inhibitedphotosynthesis.     

浙江省SARS冠状病毒分离与系统进化树分析

从浙江省3例SARS患者中收集含漱液标本,经处理后接种Vero、RD、VeroE6和Hep-2细胞进行病毒分离,培养3d后在Vero和RD细胞中可观察到细胞病变。从细胞培养上清中提取病毒核酸,用SARS冠状病毒特异性引物进行RT-PCR,并经测序证实从3份临床样本中分离到2株SARS冠状病毒株。对其中1株病毒的基因组进行了全序列测定并作系统进化树分析显示浙汀省SARS冠状病毒株与新加坡2774株和台湾TW1株最为接近。     

乳腺纤维瘤蛋白质组的凝胶内差异显示电泳分析

目的:建立具有高分辨率和稳定性的乳腺纤维瘤组织蛋白质组的双向电泳图谱,并对其进行差异蛋白质组分析.方法:取乳腺纤维瘤病患者病变部位及正常乳腺组织,匀浆提取乳腺组织总蛋白,分别用Cy3或Cy5标记,每一时Cy3和cy5标记样品都与一个Cy2标记的内标等量混合,上样于同一胶中进行电泳分离,经不同光激发下扫描得到不同样品的蛋白质组图谱.所获得的图谱经DeCyder软件分析.结果:在乳腺纤维瘤病的病变组织中,有37个蛋白质表达水平显著增加,另外8个蛋白质表达水平显著下降.结论:分析所得的45个差异蛋白质可能与乳腺纤维瘤疾病的发生与发展有关.     

Climate change causes rapid changes in the distribution and site abundance of birds in winter

Detecting coherent signals of climate change is best achieved by conducting expansive, long‐term studies. Here, using counts of waders (Charadrii) collected from ca. 3500 sites over 30 years and covering a major portion of western Europe, we present the largest‐scale study to show that faunal abundance is influenced by climate in winter. We demonstrate that the ‘weighted centroids’ of populations of seven species of wader occurring in internationally important numbers have undergone substantial shifts of up to 115 km, generally in a northeasterly direction. To our knowledge, this shift is greater than that recorded in any other study, but closer to what would be expected as a result of the spatial distribution of ecological zones. We establish that year‐to‐year changes in site abundance have been positively correlated with concurrent changes in temperature, but that this relationship is most marked towards the colder extremities of the birds' range, suggesting that shifts have occurred as a result of range expansion and that responses to climate change are temperature dependent. Many attempts to model the future impacts of climate change on the distribution of organisms, assume uniform responses or shifts throughout a species' range or with temperature, but our results suggest that this may not be a valid approach. We propose that, with warming temperatures, hitherto unsuitable sites in northeastern Europe will host increasingly important wader numbers, but that this may not be matched by declines elsewhere within the study area. The need to establish that such changes are occurring is accentuated by the statutory importance of this taxon in the designation of protected areas.