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Hemoglobin, haptoglobin, and transferrin phenotypes were determined by means of starch-gel electrophoresis for a sample of 226 Kenya hospital patients. Allele frequencies were: HbβS=0.081; Hp1=0.057; TfD=0.038. Hemoglobin S was the only aberrant hemoglobin found in this sample. Transferrins C and D were the only transferrins found. Hemoglobin and transferrin phenotypes were also determined for a sample of 201 newborn Kenya infants. One of these infants had hemoglobins F, S, and C, eight had hemoglobins A, F, and S, and the remainder had hemoglobins A and F. Transferrins C, B, and D were found in this sample. Allele frequencies were: TfB=0.008; TfD=0.019.  相似文献   

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The seed of more than 12,000 variations of Indian corn have been collected from many areas in the Western Hemisphere, and are preserved at regional centers to provide genetic factors in the future breeding of agronomically improved, disease-resistant and higher yielding varieties.  相似文献   

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Malaysian enzyme industry is considered almost non-existence, although the import volume is large. Realizing the importance of enzymes, encompassing a wide range of applications in bioindustry, the development of home grown technologies for enzyme production and applications becomes one of the national priorities in industrial biotechnology. Enzyme production from indigenous microbial isolates was performed either by submerged or solid state fermentation processes. Based on its wide and unique spectrum of properties, enzymes have been developed for wide applications in various industrial processes. The development of the enzyme catalysed applications is based on the modification of the reaction systems to enhance their catalytic activities. Some of the applications of the industrial enzymes include the fine chemicals production, oleochemicals modification, detergent formulation, enzymatic drinking of waste papers, animal feed formulation and effluent treatment processes. Enzymes have also shown to be successfully used as analytical tool in the determination of compounds in body fluids. Although, most of these enzyme catalysed reactions were performed in aqueous phase, the use of enzymes in organic solvents was found to be significant for the production of new chemicals.  相似文献   

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Coliphage and indigenous phage in Mamala Bay, Oahu, Hawaii.   总被引:5,自引:2,他引:5       下载免费PDF全文
Public concern over the discharge of primarily treated sewage by two offshore outfalls in Mamala Bay, Oahu, prompted a multidisciplinary study to determine the impact of such activities on the water quality in the bay and at adjacent recreational beaches. As part of this study, we determined the abundance of coliphage as an indicator of fecal pollution along with total viral direct counts and phages infective for Vibrio parahaemoltyicus 16 at stations in Mamala Bay in four quarterly samplings over 13 months. Coliphage (< 1 to 1.2 x 10(3)/liter) were found during each quarterly sampling along an offshore transect to the Sand Island waste treatment facility outfall. The nonpoint coastal stations (Pearl Harbor, Ala Wai Canal, and Ke'ehi Lagoon) had high levels of coliphage during the storm event sampling in February 1994 but much lower levels or none when sampled during dry weather. Coliphage were absent at all samplings at Waikiki Beach and at the control station off Diamond Head. Viral direct counts in eutrophic coastal stations (Pearl Harbor, Ke'ehi Lagoon, Ala Moana Beach, and Ala Wai canal) averaged 10(9)/liter, while counts at offshore stations ranged from 9 x 10(7) to 1 x 10(9) viruses/liter, values similar to those for other marine environments. Vibriophage were found mainly in eutrophic coastal environments (Ala Wai Canal, Pearl Harbor, and Ke'ehi Lagoon) and at the Sand Island Transect stations D1 and D2. The greatest abundance was found during the storm event (February 1994) sampling. These results suggest that the Sand Island outfall influenced the water quality of the immediate surrounding waters but had little effect on the quality of the recreational beaches. Nonpoint discharge sources appeared to be more important in the distribution of fecal indicators in the coastal zone.  相似文献   

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We explore the discourses of Mexican scientists and doctors on genetics and obesity and how these relate to ideas about race, class and national identity. Drawing on interviews with geneticists and doctors treating obese children, the paper makes two contributions to the literature on race and medical science. First, although our data reveal familiar racializing tendencies among geneticists, a more nuanced view is needed, as medical doctors who are sceptical about genetic explanations nevertheless tend to racialize, using more environmental and cultural explanations, which adduce epigenetic mechanisms. Second, rather than focusing on minority groups, as in much literature on racialization and genetics, in Mexico ideas about racialized genetic (and cultural) ancestry also impinge on the majority “mestizo” (mixed-race) population, opening broader panoramas of racialized pathologization. These two factors represent an overall strengthening of discourses of race in Mexico and probably in much of Latin America.  相似文献   

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These varieties, still cultivated in a primitive manner, may have value for hybridizing with Burley and Virginia tobaccos. In Venezuela the leaves are manufactured into cigars or are extracted to produce the masticatories known as “chimo” and “tobacco rope”.  相似文献   

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Gloeotrichia natans, a nitrogen fixing cyanobacterium common in rice fields in the Philippines, was used for studies to establish key features of its physiology and potential production in outdoor cultures. Under optimal growth conditions (38 °C, pH 8.0, no carbon enrichment) the specific growth rate of rice-field isolate was 0.076 h–1. The pH of the medium (between 6.5 and 9.0) did not influence the growth rate, but it did affect phycobiliprotein content, as reflected by a change in colour. At pH 7.0 the culture was green-brown, with phycobiliproteins constituting up to 10% of the total protein, while at pH 9.0 the culture was brownish-black and the pigment content was as high as 28% of the total protein. In outdoor cultures the specific growth rate was related directly to cell density in the range of 0.7–1.5 g dry weight 1–1 at a rate of stirring of 30 rpm, and inversely related to cell density at half this rate. At a stirring of 30 rpm, daily production of outdoor cultures harvested to maintain cell densities of 0.7, 1.15 andw 1.5 g 1–1 were 14.7, 17.1 and 18.1 g m–2 dt, respectively. This rate of production was maintained for more than 45 days. Phycobiliprotein content in the culture kept at a density of 1.5 g 1–1 reached 14% of the total biomass.  相似文献   

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Density,activity, and diversity of bacteria indigenous to a karstic aquifer   总被引:2,自引:0,他引:2  
The microbial ecology of karstic ground water is largely unknown. The density, activity, and diversity of bacteria indigenous to subsurface karstic material in Mammoth Cave National Park, Mammoth Cave, Kentucky were studied using minimally disruptive, on-site procedures. Two sites, located 100 m below the surface and consisting of saturated fine to coarse sand in pooled water, were examined. Samples were taken aseptically using modified, sterile 60-cc syringes. Total cell and total respiring cell densities were determined using an acridine orange/p-iodonitrotetrazolium violet (AO/INT) staining procedure. Cells in selected cores were stained with INT and incubated in the cave for 4 h prior to fixing with glutaraldehyde and subsequent transport to the laboratory. Cells were stained with AO in the laboratory. Low- and high-nutrient media were used to determine viable cell counts. Plates were incubated in the cave for 1 day at ambient temperature prior to transportation to the laboratory in an insulated cooler. Viable cell counts ranged from 1.0 × 106 to 8.1 × 106 cells wet g–1 of sediment. Total direct counts were 3.9 × 106 and 1.4 × 107 cells wet g–1 for the Olivia's Dome and the Catherine's Dome sites, respectively. Viable cell counts were highly similar to respiring cell counts at both sites. At the Olivia's Dome site, viable cell counts represented 26–31% of the direct cell counts, while 58% of the total cell count were actively respiring. At the Catherine's Dome site, viable cell counts represented 11–58% of the direct counts, while 53% of the cells were actively respiring. A total of 237 strains recovered from low- and high-nutrient media at both Olivia's and Catherine's Domes, and 10 reference strains were examined for 117 morphological, biochemical, and physiological characteristics. Results were coded in a binary fashion and analyzed using numerical taxonomic techniques. Similarity values were calculated using a simple matching coefficient. Fifty-two clusters, ranging in size from 2 to 13 members, were defined at the 80–85% similarity level with the weighted pair-group mathematical average algorithm (WPGMA). The matrix was examined using the Jaccard coefficient and WPGMA clustering to control for distortion due to negative matches and varying group size. Presumptively identified genera include, Arthrobacter, Brevibacterium, Bacillus, Cornyebacterium, Actinomyces, Aureobacterium, Chromobacterium, and Mycobacterium. Pseudomonas spp. were not recovered. Fifty percent of the clustered operational taxonomic units (OTUs) were not identified. Thirty percent of the clustered OTUs were irregular, asporogenous, Gram-positive rods. The bacterial communities varied between sites, and isolation medium had a strong influence on the strains recovered. The bacterial community in the karstic sediments sampled exhibits a high degree of diversity having no dominant strain or strains.Correspondence to: K.J. Rusterholtz  相似文献   

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A survey of Tapinanthus bangwensis was carried out in a plantation in the botanic garden at Amani Nature Reserve, which forms part of the East Usambara Mountain, located in the north‐east of Tanzania. A total of 169 trees were examined on four transects of 100 × 50 m (5000 m2) each, located about 700 m apart. Three treatment transects were established in open woodland with a control transect in the closed canopy. Out of 101 trees (81 non‐indigenous and 20 indigenous) examined in the open canopy, T. bangwensis was present on 24; eighteen non‐indigenous and six indigenous. Of all the infested trees, a non‐indigenous species, silky oak (Grevillea robusta) was the most common (37.4%), followed by an indigenous species, mzindanguruwe (Blighia unijugata) with 16.6%. Chi‐squared tests showed that there was no significant difference in frequency of infestation between non‐indigenous and indigenous species (χ2 = 0.715, P = 0.5826). t‐Testing showed that T. bangwensis preferred taller and larger trees (t = ? 3.930, P = 0.0002 and t = ? 2.416, P = 0.0175, respectively). No T. bangwensis was found on the 68 trees examined in the closed canopy.  相似文献   

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This article draws on fieldwork carried out in a Guaraní-speaking community in the Bolivian Chaco – Isoso – between 1997 and 2000. At the time, some Isoseño people were employed in urban-headquartered projects that revolved around Isoso's environment, culture, or identity and that were funded multilaterally by grants, loans, or other foreign aid. The article describes a set of fantastic discourses circulating in rural Isoso that seem to compare a magical place called Salamanca to the city where some Isoseño people now work. The article argues that these Salamanca discourses are an Isoseño-specific way of talking about a general set of unprecedented processes. It takes up the fact that undertakings of the kind in which the Isoseño are involved create new calibrations among radically different systems for moral/qualitative and material/ quantitative evaluation which can most 'economically' be expressed in terms of credit and debt. Finally, it considers why it is that for all their strange magic, Isoseño 'Salamanca and the city' discourses put an extremely recognizable suite of moral considerations at their centre.  相似文献   

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The parasite-host-environment system is dynamic, with several points of equilibrium. This makes it difficult to trace the thresholds between benefit and damage, and therefore, the definitions of commensalism, mutualism, and symbiosis become worthless. Therefore, the same concept of parasitism may encompass commensalism, mutualism, and symbiosis. Parasitism is essential for life. Life emerged as a consequence of parasitism at the molecular level, and intracellular parasitism created evolutive events that allowed species to diversify. An ecological and evolutive approach to the study of parasitism is presented here. Studies of the origin and evolution of parasitism have new perspectives with the development of molecular paleoparasitology, by which ancient parasite and host genomes can be recovered from disappeared populations. Molecular paleoparasitology points to host-parasite co-evolutive mechanisms of evolution traceable through genome retrospective studies.  相似文献   

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Finer M  Jenkins CN  Pimm SL  Keane B  Ross C 《PloS one》2008,3(8):e2932

Background

The western Amazon is the most biologically rich part of the Amazon basin and is home to a great diversity of indigenous ethnic groups, including some of the world''s last uncontacted peoples living in voluntary isolation. Unlike the eastern Brazilian Amazon, it is still a largely intact ecosystem. Underlying this landscape are large reserves of oil and gas, many yet untapped. The growing global demand is leading to unprecedented exploration and development in the region.

Methodology/Principal Findings

We synthesized information from government sources to quantify the status of oil development in the western Amazon. National governments delimit specific geographic areas or “blocks” that are zoned for hydrocarbon activities, which they may lease to state and multinational energy companies for exploration and production. About 180 oil and gas blocks now cover ∼688,000 km2 of the western Amazon. These blocks overlap the most species-rich part of the Amazon. We also found that many of the blocks overlap indigenous territories, both titled lands and areas utilized by peoples in voluntary isolation. In Ecuador and Peru, oil and gas blocks now cover more than two-thirds of the Amazon. In Bolivia and western Brazil, major exploration activities are set to increase rapidly.

Conclusions/Significance

Without improved policies, the increasing scope and magnitude of planned extraction means that environmental and social impacts are likely to intensify. We review the most pressing oil- and gas-related conservation policy issues confronting the region. These include the need for regional Strategic Environmental Impact Assessments and the adoption of roadless extraction techniques. We also consider the conflicts where the blocks overlap indigenous peoples'' territories.  相似文献   

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Five male and 9 female house musk shrews (Suncus murinus) captured in Koralawella, Sri Lanka were acquired by our laboratory. One male and 3 females alone contributed to the development of a new laboratory line (SRI line). The SRI line has been maintained as a closed breeding colony consisting of more than 40 shrews. Gestation period and litter size at birth averaged 31.2 days (43 cases) and 2.4 (43 litters), respectively. The SRI line shrews were uniformly covered with light gray fur. The body weight and total length of adult shrews averaged 72.9 g and 23.9 cm in males, and 49.6 g and 21.0 cm in females. These data indicate a body size intermediate between BAN line shrews originating from Bangladesh and Nag or OKI line shrews from Japan. The SRI shrews are also characterized by having 30 chromosomes in diploid, being the smallest number in the entire species, whereas the otherlines (Nag, OKI and BAN) all have 40 chromosomes.  相似文献   

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