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91.
Arbuscular mycorrhizal fungi (AMF) were surveyed for species richness and abundance in sporulation in six distinct land uses in the western Amazon region of Brazil. Areas included mature pristine forest and sites converted to pasture, crops, agroforestry, young and old secondary forest. A total of 61 AMF morphotypes were recovered and 30% of them could not be identified to known species. Fungal communities were dominated by Glomus species but Acaulospora species produced the most abundant sporulation. Acaulospora gedanensis cf., Acaulospora foveata, Acaulospora spinosa, Acaulospora tuberculata, Glomus corymbiforme, Glomus sp15, Scutellospora pellucida, and Archaeospora trappei sporulated in all land use areas. Total spore numbers were highly variable among land uses. Mean species richness in crop, agroforestry, young and old secondary forest sites was twice that in pristine forest and pasture. fungal communities were dominated in all land use areas except young secondary forest by two or three species which accounted for 48% to 63% of all sporulation. Land uses influenced AMF community in (1) frequency of occurrence of sporulating AMF species, (2) mean species diversity, and (3) relative spore abundance. Conversion of pristine forest into distinct land uses does not appear to reduce AMF diversity. Cultural practices adopted in this region maintain a high diversity of arbuscular mycorrhizal fungi.  相似文献   
92.
The genetic map of Bremia lactucae was expanded utilizing 97 F(1) progeny derived from a cross between Finnish and Californian isolates (SF5xC82P24). Genetic maps were constructed for each parent utilizing 7 avirulence genes, 83 RFLP markers, and 347 AFLP markers, and a consensus map was constructed from the complete data set. The framework map for SF5 contained 24 linkage groups distributed over 835cM; the map for C82P24 contained 21 linkage groups distributed over 606cM. The consensus map contained 12 linkage groups with markers from both parents and 24 parent-specific groups. Six avirulence genes mapped to different linkage groups; four were located at the ends of linkage groups. The closest linkages between molecular markers and avirulence genes were 3cM to Avr4 and 1cM to Avr7. Mating type seemed to be determined by a single locus, where the heterozygote determined the B(2) type and the homozygous recessive genotype determined the B(1) type.  相似文献   
93.
Oswaldo Castro 《Cryobiology》1982,19(4):339-345
Metabolic features and in vivo recovery of cryopreserved cyanate-treated erythrocytes from patients with sickle cell anemia were studied. Red cells were treated with the anti-sickling agent sodium cyanate, glycerolized, and frozen at ?80 °C. Cyanate increased post-thaw hemolysis of both normal and sickle erythrocytes. The thawed carbamylated sickle erythrocytes maintained high oxygen affinity but lost more than half of their ATP content. Addition of the metabolic nutrients adenine, pyruvate, and inosine (rejuvenation) during cyanate incubation prevented ATP loss. Rejuvenation also increased red cell 2,3-DPG and opposed the cyanate effect by lowering oxygen affinity. Yet cyanate improved by nearly 50% the intravascular recovery of thawed rejuvenated sickle erythrocytes in a rat transfusion model. Cryopreservation of autologous cyanate-treated erythrocytes could lead to their use as an extracorporeal treatment of sickle cell disease.  相似文献   
94.
Among 17 species and cultivars of plants exposed to Anguina plantaginis, only Plantago aristata (bracted plantain) was a host. Larvae penetrated the emerging apical meristem; reproduces and migrated progressively; caused twisting and galling of leaves, looping andspiraling of peduncles, and transformation of floral structures into galls. Extreme infections caused stunting and death of entire plants. Hypertrophy and hyperplasia of leaf mesophyll, cell separation and disintegration, and xylem wall thickening in older galls occurred. Only third-stage larvae were infective, and they exhibited cryptobiosis under adverse conditions.  相似文献   
95.
The BioMoby project was initiated in 2001 from within the modelorganism database community. It aimed to standardize methodologiesto facilitate information exchange and access to analyticalresources, using a consensus driven approach. Six years later,the BioMoby development community is pleased to announce therelease of the 1.0 version of the interoperability framework,registry Application Programming Interface and supporting Perland Java code-bases. Together, these provide interoperable accessto over 1400 bioinformatics resources worldwide through theBioMoby platform, and this number continues to grow. Here wehighlight and discuss the features of BioMoby that make it distinctfrom other Semantic Web Service and interoperability initiatives,and that have been instrumental to its deployment and use bya wide community of bioinformatics service providers. The standard,client software, and supporting code libraries are all freelyavailable at http://www.biomoby.org/.   相似文献   
96.
97.
Gene expression in response to the copper sulfide, covellite (CuS), in Acidithiobacillus ferrooxidans LR was investigated by using RNA arbitrarily primed polymerase chain reaction (RAP-PCR). Seven genes that encode for proteins involved with transport and binding were up-regulated in the presence of CuS. The differential expression of the seven genes was confirmed by real-time PCR. An atomic absorption analysis of the covellite samples showed that the quantity of copper(II) ions in solution changed from zero to approximately 1.11 g/l after 24 h, and the pH changed from 1.8 to 4.0, suggesting that the copper ions in solution and the pH alteration may be responsible, at least in part, for the up-regulation of the transporter genes in the presence of covellite. An in silico protein–protein interaction analysis of the proteins encoded by the seven transporter protein genes, as well as of proteins encoded by genes of the same functional category that are adjacent to the seven genes identified by RAP-PCR, showed that besides the correlated function, the transporter proteins may act in different steps of the bacterial response to covellite.  相似文献   
98.
Engene is a versatile, and platform-independent web tool for exploratory analysis of gene expression data that aims at storing, visualizing and processing large sets of gene expression patterns.  相似文献   
99.
Extremophiles - The research and education mine “Reiche Zeche” in Freiberg (Saxony, Germany) represents one of the most famous mining facilities reminiscent to the century-long history...  相似文献   
100.
Dioscorea howardiana is proposed as a new species from Mexico and Central America as far south as Panama, and is described and illustrated. It most closely resemblesD. liebmannii. Relationships, distribution, and ecological preferences of the new species are discussed.
Resumen   Dioscorea howardianase propone como una especie nueva de México y Centroamérica, es descrita e ilustrada. Es semejante aD. liebmannii. Se discuten sus relaciones, su distribución geográfica y preferencias ecológicas.
  相似文献   
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