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991.
A species of the genus Gonoclostera Butler, 1877, G.fangi sp.nov., from Yunnan, China is described in the present paper. Generic diagnosis and list of world species, as well as the photos of adults and genitalia of the new species are also provided.  相似文献   
992.
993.

Purpose  

Cadmium (Cd) is a toxic heavy metal, accumulated in soil by anthropogenic activities and has serious effects on soil microbial activities in contaminated soils. Moreover, there is a lack of reliable data on the effects of Cd in the soil-plant system, since most of the information on Cd-microorganism interactions in soils are based on sewage sludge without plants. The main objective of this study was to assess the effects of Cd on soil microbial activities and community structure during growth of plant.  相似文献   
994.
995.
996.
Calcium plays a major role in plant growth and development and in the maintenance and modulation of various cell functions, especially related to membrane structure and function and to cell wall structure. Calcium stabilizes cell membranes by bridging polar head groups of phospholipids at the membrane surface. Calcium is also an integral part of the cell wall where it provides stable intra-molecular linkages between pectin molecules, resulting in cell wall rigidity. A change in the cytosolic calcium concentration is also known to provide a cellular signal that regulates metabolism and mediates plant responses to stresses.  相似文献   
997.
A progressive part of protected area management program in Lao PDR is a land and forest allocation program which contains critical elements that delegate right of land and forest use to local people. This study analyzes the gap between the original intent of the program and its actual implementation by local officials in Phou Xang He protected area, and discusses policy issues that need to be addressed. It appears that several types of non-compliance with regulations by local people have occurred, with local officials tacitly ignoring infractions. By switching viewpoints, however, it appears that the local officials permit these infractions as a way of allowing local people to secure their livelihoods. As constraints on the realities of land and forest use vary widely in and around villages in different locales, there is a need for government to allow local officials flexibility in implementing policies.  相似文献   
998.
The occurrence of pathologically changed muscular fibers in some wild species of birds and in economically important domesticated species of birds is described. The hydrops of muscular fibers, necrosis and atrophy with connective tissue infiltration in muscular bundles were detected in breast and thigh muscles in wild birds, e. g. in raven, pigeon and pheasant. The same pathological processes were also found in domesticated species, e. g. in guinea fowl, less often in geese and duck. Their incidence in turkeys and laying types of fowl was more frequent, they were observed most often in muscles of broiler hens. Fission of muscular fibers, very thin, but also hypertrophic fibers and resorption of necrotic fibers were detected in hens besides the above changes. The described histological picture is confronted with the picture of hereditary myodystrophy in chickens.  相似文献   
999.
Tubulin was estimated to account for 0.3% of the total soluble protein in Trichinella spiralis cytosolic fractions. Tubulin from T. spiralis was partially purified by precipitation with either taxol or vinblastine sulphate. Immunoblotting with alpha- and beta-tubulin monoclonal antibodies revealed the presence of tubulin in T. spiralis partially purified preparations. Electrophoretic mobility of T. spiralis tubulin in sodium dodecyl sulphate-polyacrylamide gels was very similar to that shown by pig brain tubulin. Further studies with colchicine binding assays indicated that T. spiralis tubulin has binding features similar to that of tubulin from other nematodes: colchicine association constant = 8.1 x 10(-4) M and competitive inhibition of colchicine binding by podophyllotoxin, with an inhibition constant of 1.3 x 10(-6) M. Finally, inhibition of colchicine binding by several benzimidazoles (mebendazole, fenbendazole, oxibendazole and albendazole) was investigated. All the benzimidazoles inhibited colchicine binding in a competitive manner, with inhibition constant values ranging from 1.4 x 10(-7) M (mebendazole) to 3.9 x 10(-6) M (fenbendazole).  相似文献   
1000.
The prevalence of enzootic bovine leukosis (EBL) in Turkey was investigated by serological screenings using the agargel immunodiffusion test (AGID). A total of 4,047 blood samples obtained from 2,780 cattle between one and 14 years of age and taken in 6-8 month-intervals in three dairy farms were tested for the presence of EBL-specific antibodies. A high prevalence of EBL-sero-positive animals was found amongst cattle in two of the farms. Furthermore, recommendations based upon the regulation implemented by an expert group of the European Commission and considering the local dairy management conditions were presented.  相似文献   
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