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111.
The distribution and economic losses of alien species invasion to China   总被引:9,自引:0,他引:9  
Invasive alien species have become one of the most serious environmental issues in the world. Data of taxon, origin, pathway, and environmental impacts of invasive alien microorganisms, invertebrates, amphibians and reptiles, fish, birds, mammals, herbs, trees, and, marine organisms in terrestrial, aquatic, and marine ecosystems of China were analyzed during 2001 and 2003, based on literature retrieval and field survey. There were 283 invasive alien species in China, and the number of species of invasive alien microorganisms, aquatic plants, terrestrial plants, aquatic invertebrates, terrestrial invertebrates, amphibians and reptiles, fish, and mammals were 19, 18, 170, 25, 33, 3, 10, and 5, respectively. The proportion of invasive alien species originated from America, Europe, Asia, Africa, and Oceania were 55.1, 21.7, 9.9, 8.1, and 0.6%, respectively. Methods for estimation of direct economic losses to agriculture, forestry, stockbreeding, fishery, road and water transportation, storage, water conservancy, environment and public facilities, and human health were established. Methods for estimation of indirect economic losses caused by invasive alien species to service functions of forest ecosystems, agricultural ecosystems, grassland ecosystems, and wetland ecosystems were also established. The total economic losses caused by invasive alien species to China were to the time of USD 14.45 billion, with direct and indirect economic losses accounting for 16.59% and 83.41% of total economic losses, respectively.  相似文献   
112.
The status and causes of alien species invasion in China   总被引:5,自引:0,他引:5  
Data of classification, origin, pathway and environmental impacts of invasive alien micro-organisms, invertebrates, amphibians and reptiles, fish, birds, mammals, weeds, trees, and marine organisms in terrestrial, aquatic and marine ecosystems of China, were analyzed, based on literature retrieval, field survey and consultation. Some 283 invasive alien species were recorded in China, including 19 invasive alien micro-organisms, 18 aquatic plants, 170 terrestrial plants, 25 aquatic invertebrates, 33 terrestrial invertebrates, 3 amphibians and reptiles, 10 fish, and 5 mammals. Of the invasive alien species, 55.1% originated from North and South America, 21.7% from Europe, 9.9% from Asia, 8.1% from Africa and 0.6% from Oceania. Many institutions and individuals in China lack adequate knowledge of ecological and environmental consequences caused by invasive alien species, with some ignorance of the dangerous invasion in the introduction of alien species. For instance, 50.0% of invasive alien plants were intentionally introduced as pasture, feedingstuff, ornamental plants, textile plants, medicinal plants, vegetables, or lawn plants, 25% of alien invasive animals were intentionally introduced for cultivation, ornament, or biological control, In addition, more efforts are being made in the introduction of alien species, and little attention is paid on the management of introduced alien species, which may cause their escape into natural environment and potential threats to the environment. There were also gaps in quarantine system in China. All microorganisms were unintentionally introduced, through timber, seedling, flowerpot, or soil; 76.3% of alien invasive animals invaded through commodity or transportation facility because of the failure of quarantine. Therefore, quarantine measures should be strictly implemented; and meanwhile the intentional introduction of alien species should be strictly managed and a system of risk assessment should be implemented.  相似文献   
113.
This paper reports a new species and two new records of the Axinidae collected from fishes of the South China Sea. Loxuroides fungilliformis n. sp. was obtained from the gills of Hemirhamphus guoyi collected at Zhapo (21°34N, 111°49E). The new species is similar to L. sasikala (Unnithan,1957) Price, 1962 in the structure of the cirrus and genital atrium, but differs from the latter in the shape and number of the spines of its genital atrium and cirrus. Both L. sasikala and Axine tripathii Price, 1962 are recorded for the first time off China.  相似文献   
114.
In the present study, we measured the levels of immunoglobulin (Ig)- and complement 3 (C3)-determined circulating immune complexes (two-component-determined CIC, or TCIC) in hepatitis C virus (HCV)-infected patients. TCIC was dissected into C3/Ig-TCIC and Ig/C3-TCIC by a reciprocal use of coating and detecting antibodies. The current study was carried out in 117 infected HCV patients and 252 healthy controls. We found that C3/Ig-TCIC elevation was a common feature in patients with HCV infection. Positive rates and levels of C3/IgG-TCIC and C3/IgM-TCIC were significantly higher in the patients with abnormal alanine aminotransferase (ALT) than patients with normal ALT (70.6% vs. 17.0%, 0.56 OD vs. 0.47 OD and 0.71 OD vs. 0.65 OD, respectively, P<0.001). However, the levels of IgM/C3-TCIC and IgA/C3-TCIC were significantly higher in individuals with HCV infection than in healthy controls, whereas the level of IgG/C3-TCIC was significantly lower in the former group than in the latter group. In summary, our results suggest that IgG and C3 TCIC may play an important role in liver cell injury during the course of HCV infection and may be a hallmark for hepatitis C pathogenesis. Elevated C3/Ig-TCIC, accompanied by decreased Ig/C3-TCIC, forms a peculiar trait in HCV infection. Our findings thus provide new insights into HCV pathogenesis.  相似文献   
115.
PARP-1 activation by H(2)O(2) in an acute preparation of superfused, respiring, neonatal cerebrocortical slices was assessed from PAR-polymer formation detected with immunohistochemistry and Western blotting. (31)P NMR spectroscopy at 14.1 Tesla of perchloric acid slice extracts was used to assess energy failure in a 1-h H(2)O(2) exposure as well as in a subsequent 4-h recovery period where the superfusate had no H(2)O(2) and specifically chosen metabolic substrates. Although more data are needed to fully characterize different bioenergetic responses, a high NMR spectral resolution (PCr full-width at half-max approximately.01 ppm) and narrow widths for most metabolites (<.2 ppm) permitted accurate quantifications of spectrally resolved resonances for ADP, ATP, NAD(+)/NADH, and other high energy phosphates. It appears possible to use brain slices to quantitatively study PARP-related, NAD-associated energy failure, and rescue with TCA metabolites.  相似文献   
116.
An in vitro system was created to study the process of membrane protein degradation by using photosystem I (PS1) as a model membrane protein. Purified chloroplast membranes were incubated at 30 degrees C in a defined buffer along with various extracts or reagents to reconstitute the disassembly and degradation of PS1, which was monitored by a variety of techniques that probe the integrity of the PS1 complex: photo-biochemical assays, semi-native gel electrophoresis, low temperature fluorescence spectroscopy, and immunoblots using antibodies against different PS1 subunits. During a typical time course, degradation of PS1 appeared to be a multievent process, with disassembly of the complex preceding proteolysis of the subunits. The first change seen was a rapid (<5 min) decrease in PS1 photochemical activity. This was followed by a diminution of far-red fluorescence emission from the core antenna of PS1 and a slower disassembly of the PS1 chlorophyll-protein core complex, as visualized by semi-native gel electrophoresis. Surprisingly, the latter was not accompanied by a similar rate of proteolysis of the PsaA core subunit. In contrast, addition of soluble proteases caused rapid loss of immuno-detectable PS1 polypeptides and cleavage of the major PS1 polypeptides in interhelical loops. The in vitro degradation process was time- and temperature-dependent but did not require ATP, GTP, or soluble chloroplast proteins. Chelation of divalent cations by EDTA inhibited the later steps of disassembly and proteolysis, and this effect could be reversed by addition of micromolar Zn2+, with Co2+ and Ca2+ providing somewhat lower activity.  相似文献   
117.
在CITYgreen模型支持下,以1994年与2004年的杭州市Landset TM数据提取的土地利用信息与绿地分布数据为基础,对杭州市人工绿地、人工林地与天然林地的生态服务价值进行估算和对比分析,研究杭州市土地利用变化和经济发展状况对其的影响.结果表明,10年间,杭州市绿地虽然减少了20.4%,但绿地生态服务价值增加了1.68×109元,绿地生态服务价值与杭州市GDP年度增长率分别为111.92%和5.32%,适宜的土地利用调整有效地协调了城市经济发展与城市生态功能的关系,实现了土地利用的生态服务高效能.  相似文献   
118.
Niu L  Li J  Chen J  Zhou L  Wu B  Zeng J  Fang G  Deng C  Yao F  Chen Z  Leng Y  Deng M  Deng C  Zhang B  Liao M  Xu K  Zuo J  Xu K 《Cryobiology》2012,64(3):245-249
The purpose of this study was to compare a dual-freeze protocol with a triple-freeze protocol for pulmonary cryoablation in a porcine lung model. Five dual- (10-5-10-5) and five triple-freeze (5-5-5-5-10-5) cryoablations were performed on an exposed operation field in normal porcine lung. Changes in the temperature of the cryoprobes and the diameter of the iceballs were measured during the ablation and pathologic changes in the cryozones (zones of tissue destruction) were reviewed 7 days after the procedure. The diameter of the iceball surface differed between the two protocols. Pathologically, the triple-freeze protocol was associated with a longer complete necrosis zone than the dual-freeze protocol, though the two protocols produced cryolesions and cryozones of similar length, and in both cases there were five areas of tissue destruction. With the same duration of freezing (20 min), the triple-freeze protocol may be better for pulmonary cryoablation than the dual-freeze protocol.  相似文献   
119.
120.
A new structural class of potent prolylcarboxypeptidase (PrCP) inhibitors was discovered by high-throughput screening. The series possesses a tractable SAR profile with sub-nanomolar in vitro IC(50) values. Compared to prior inhibitors, the new series demonstrated minimal activity shifts in pure plasma and complete ex vivo plasma target engagement in mouse plasma at the 20 h post-dose time point (po). In addition, the in vivo level of CNS and non-CNS drug exposure was measured.  相似文献   
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