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1.
The effect of trace metals on the mesophilic methane fermentation of high-solid food waste was investigated using both batch and continuous experiments. The continuous experiment was conducted by using a CSTR-type reactor with three run. During the first run, the HRT of the reactor was stepwise decreased from 100 days to 30 days. From operation day 50, the reactor efficiency deteriorated due to the lack of trace metals. The batch experiment showed that iron, cobalt, and nickel combinations had a significant effect on food waste. According to the results of the batch experiment, a combination of iron, cobalt, and nickel was added into the CSTR reactor by two different methods at run II, and III. Based on experimental results and theoretical calculations, the most suitable values of Fe/COD, Co/COD, and Ni/COD in the substrate were identified as 200, 6.0, and 5.7 mg/kg COD, respectively.  相似文献   

2.
The pathogenesis of human benign prostatic hyperplasia (BPH) has not been fully elucidated. There is, however, evidence that estrogens—besides other factors—might play an important role for the growth of the prostate. Consequently, estrogen deprivation might be a new, useful principle for a conservative treatment of BPH. Atamestane, a new, highly selective steroidal aromatase inhibitor has been proven to be successful in antagonizing experimentally-induced estrogen-related stromal overgrowth of the prostate in dogs and monkeys. Double-blind placebo controlled studies are now underway in Europe and the U.S.A. It is anticipated that these studies will give us a definite answer of the clinical validity of this concept in BPH patients in the near future. However, it is very important to take into consideration that for an effective treatment of BPH, a reduction of both the glandular and stromal elements has to be achieved. In other words, both androgens and estrogens seem to be involved in the regulation of (over)growth of the prostate. Therefore, a combination of an androgen and estrogen deprivation might be a more promising approach than any single treatment.  相似文献   

3.
Available experimental evidence suggests that there are genetic differences in the abilities of trees to compete for resources, in addition to non-genetic differences due to micro-site variation. The use of indirect genetic effects within the framework of linear mixed model methodology has been proposed for estimating genetic parameters and responses to selection in the presence of genetic competition. In this context, an individual’s total breeding value reflects the effects of its direct breeding value on its own phenotype and its competitive breeding value on the phenotype of its neighbours. The present study used simulated data to investigate the relevance of accounting for competitive effects at the genetic and non-genetic levels in terms of the estimation of (co)variance components and selection response. Different experimental designs that resulted in different genetic relatedness levels within a neighbourhood and survival were other key issues examined. Variances estimated for additive genetic and residual effects tended to be biased under models that ignored genetic competition. Models that fitted competition at the genetic level only also resulted in biased (co)variance estimates for direct additive, competitive additive and residual effects. The ability to detect the correct model was reduced when relatedness within a neighbourhood was very low and survival decreased. Selection responses changed considerably between selecting on breeding value estimates from a model ignoring genetic competition and total breeding estimates using the correct model. Our results suggest that considering a genetic basis to competitive ability will be important to optimise selection programmes for genetic improvement of tree species.  相似文献   

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I Matsuda  Y Ohtani  K Ohyanagi  S Yamamoto 《Enzyme》1987,38(1-4):251-255
Carnitine status was evaluated in 8 patients with partial ornithine transcarbamylase (OTC) deficiency and 19 patients with secondary carnitine deficiency, who were used as positive references. Laboratory findings indicated that all patients with OTC deficiency had secondary carnitine deficiency especially in hyperammonemic attack. After L-carnitine administration in 2 patients with OTC deficiency, the number of attacks was significantly reduced in both cases.  相似文献   

6.
Summary This paper presents an overview of aspects of N2-fixation in phototrophic N2-fixers. Nitrogenase is little different in phototrophs from other organisms. Evidence suggests that fixed carbon dissimilation rather than direct photoreduction from oxidised inorganic compounds or exogenous photosynthetic electron donors is the major route of reductant supply to nitrogenase in phototrophs; inRhodospirillum rubrum pyruvate is a possible electron donor to nitrogenase; in cyanobacteria the oxidative pentose phosphate pathway is important, although some recent evidence implicates glycolysis and the tricarboxylic acid cycle in reductant supply in heterocystous cyanobacteria. In photosynthetic organisms light modulation of various enzymes occurs-some Calvin cycle enzymes are light activated, some oxidative pentose phosphate pathway and glycolytic enzymes are deactivated and some tricarboxylic acid cycle enzymes are activated. Reduced levels of thioredoxin in heterocysts may contribute to the sustained functioning of the oxidative pentose phosphate pathway in heterocysts in the light and dark. In photosynthetic bacteria such asRhodospirillum rubrum an activating enzyme which removes a modifying group from inactive Fe protein can activate nitrogenase. O2 and NH 4 + both inhibit N2-fixation and there is some evidence in cyanobacteria that O2 stability of whole cell nitrogenase can be achieved by prolonged incubation of cultures at high O2.  相似文献   

7.
The molecular response mechanisms and signalling pathways activated upon exposure to ultraviolet (UV) radiation have been extensively studied within the last two decades. Although many signalling pathways can be activated by both UVA as well as UVB, there are several distinctions indicating wavelength-specific response patterns accommodated by the terms UVA response and UVB response. Given that human skin is primarily exposed to UV light from solar radiation consisting of both UVA and UVB, we sought to explore a potential interaction between the distinct UVA and UVB responses at the level of MAPK. Our results indicate that the two distinct stress responses elicited by UVA or UVB interact with each other, producing a "third" response that is different from either alone and cannot be explained by a simple addition of effects.  相似文献   

8.
A rapid and effective method for direct detection, selection and testing of microorganisms able to produce both cell-bound and extracellular true lipases is described. The method is based on formation of clearance zones on turbid solid media with emulsified olive oil around or under the colonies, cell fractions or culture supernatant of lipase-producing organisms. The method was successfully applied for the screening and isolation of microorganisms producing alkaline lipases. The article is published in the original.  相似文献   

9.
Fungal endophytes occurring in leaves and stems of three species of Proteaceae,Protea cynaroides, Leucospermum cordifolium andLeucadendron salignum×laureolum were investigated on farms in three locations in the Western Cape province of South Africa. The aims of this study were to determine ifBotryosphaeria proteae, a fungus that has been recorded from leaf spots ofProtea spp., was mostly restricted to leaf tissue, and whether it could occur as an endophyte in different members of Proteaceae. In this studyB. proteae was routinely isolated inProtea andLeucospermum, although it was not a dominant taxon and did not occur inLeucadendron. Botryosphaeria proteae occurred mostly in leaves, rather than stems, suggesting that it is not important as a stem canker pathogen.  相似文献   

10.
The Hungarian total (birth + fetal) prevalences of different developmental abnormalities offer a possibility to estimate the proportion of preventable development abnormalities. The effectiveness of primary, secondary and tertiary preventive methods are evaluated with a particular emphasis of primary prevention based on periconceptional folic acid or folic acid-containing multivitamin supplementation. The total prevalence of informative offspring with developmental abnormalities is 66.83 per 1,000 in Hungary and within this major DAs have 27.01 per 1,000 rate. The latter can be reduced by 26.6% by primary preventive methods due to mainly periconceptional folic acid/multivitamin supplementation. Secondary prevention particularly neonatal orthopedic screening is very effective for deformities such as congenital dislocation of the hip. Antenatal diagnoses followed by termination of pregnancy can avoid the birth of malformed newborn infants in 8.7% of DAs, however, this figure is 20 and 27% among major and multiple developmental abnormalities, respectively. Early surgical intervention can achieve a complete recovery in 33.5% of cases with developmental abnormalities. Thus there are two major conclusions: at present the major part of developmental abnormalities are preventable, however, different developmental abnormalities do not represent a single pathological category therefore there is no single strategy for their prevention.  相似文献   

11.
12.
《Biochemical education》1995,23(4):190-191
A conference on this topic sponsored by the International Union of Biochemistry and Molecular Biology (IUBMB) was held in Oxford on 11 and 12 April 1995 under the auspices of the Oxford International Biomedical Centre (OIBC)  相似文献   

13.

Background

Canine rabies is a neglected disease causing 55,000 human deaths worldwide per year, and 99% of all cases are transmitted by dog bites. In N''Djaména, the capital of Chad, rabies is endemic with an incidence of 1.71/1,000 dogs (95% C.I. 1.45–1.98). The gold standard of rabies diagnosis is the direct immunofluorescent antibody (DFA) test, requiring a fluorescent microscope. The Centers for Disease Control and Prevention (CDC, Atlanta, United States of America) developed a histochemical test using low-cost light microscopy, the direct rapid immunohistochemical test (dRIT).

Methodology/Principal Findings

We evaluated the dRIT in the Chadian National Veterinary Laboratory in N''Djaména by testing 35 fresh samples parallel with both the DFA and dRIT. Additional retests (n = 68 in Chad, n = 74 at CDC) by DFA and dRIT of stored samples enhanced the power of the evaluation. All samples were from dogs, cats, and in one case from a bat. The dRIT performed very well compared to DFA. We found a 100% agreement of the dRIT and DFA in fresh samples (n = 35). Results of retesting at CDC and in Chad depended on the condition of samples. When the sample was in good condition (fresh brain tissue), we found simple Cohen''s kappa coefficient related to the DFA diagnostic results in fresh tissue of 0.87 (95% C.I. 0.63–1) up to 1. For poor quality samples, the kappa values were between 0.13 (95% C.I. −0.15–0.40) and 0.48 (95% C.I. 0.14–0.82). For samples stored in glycerol, dRIT results were more likely to agree with DFA testing in fresh samples than the DFA retesting.

Conclusion/Significance

The dRIT is as reliable a diagnostic method as the gold standard (DFA) for fresh samples. It has an advantage of requiring only light microscopy, which is 10 times less expensive than a fluorescence microscope. Reduced cost suggests high potential for making rabies diagnosis available in other cities and rural areas of Africa for large populations for which a capacity for diagnosis will contribute to rabies control.  相似文献   

14.
Walgate R 《New biotechnology》2008,25(2-3):111-116
EAGLES investigations into the specific needs for diabetes research in developing countries, and Europe's potential to support that research [European Union and Diabetes http://ec.europa.eu/health/ph_information/dissemination/diseases/diabetes_en.htm, EU Research on Diabetes http://ec.europa.eu/research/leaflets/diabetes/index_en.html] reach nine major conclusions. In each case, they involve tuning European research to have the greatest impact in the shortest possible time, by understanding and respecting developing countries' conditions of health, politics and economics. Major recommendations arise from the lack of national population-based epidemiology to enable planning and convince political powers of the need for action; from countries' low healthcare budgets, entailing needs for the cheapest possible interventions; from the need to investigate interventions specifically tuned to national circumstances; and finally from the needs for specific local biomedical research, such as studies into the several unique African phenotypes of the disease. The details of our nine recommendations can be seen at the end of the report.  相似文献   

15.
16.
Eicosanoids represent a family of compounds derived primarily from arachidonic acid. It is now known that arachidonic acid can undergo metabolism via at least three distinct pathways, although the most readily understood are those resulting in prostaglandin or leukotriene formation via cyclooxygenase and 5-lipoxygenase, respectively. These products can be synthesized by the heart or can be released from accumulating neutrophils under various pathological conditions. Eicosanoids possess a wide array of pharmacological actions that could be of importance either in the initiation or modulation of various cardiac diseases. Here, we review the potential importance of eicosanoids to ischemic heart disease. Data are cited that examine the potential importance of these compounds to experimentally induced cardiac injury as well as clinically observed ischemic heart disease. Particular emphasis is placed on recent studies that document the relevance of endogenously synthesized arachidonic acid metabolites as well as the consequence of modulating eicosanoid synthesis through pharmacological or dietary means on cardiac injury under experimental or clinical situations.  相似文献   

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19.
Ruminal methanogens, bacteria and ciliate protozoa of Svalbard reindeer grazing natural pastures in October (late fall) and April (late winter) were investigated using molecular-based approaches. The appetite of the Svalbard reindeer peaks in August (summer) and is at its lowest in March (winter). Microbial numbers, quantified by real-time PCR, did not change significantly between October and April, when food intakes are at similar levels, although the numbers of methanogens tended to be higher in October ( P =0.074), and ciliate numbers tended to be higher in April ( P= 0.055). Similarly, no change was detected in the bacterial and protozoal population composition by rRNA gene-based denaturing gradient gel electrophoresis analysis. Dominant methanogens were identified using a 16S rRNA gene library (97 clones) prepared from pooled PCR products from reindeer on October pasture ( n =5). Eleven of the 22 distinct operational taxonomic units (OTUs) generated exhibited a high degree of sequence similarity to methanogens affiliated with Methanobacteriales (eight OTUs), Methanomicrobiales (one OTU) and Methanosarcinales (two OTUs). The remaining 11 OTUs (53% of the clones) were associated with a cluster of uncultivated ruminal archaea. This study has provided important insights into the rumen microbiome of a high-arctic herbivorous animal living under harsh nutritional conditions, and evidence suggesting that host type affects the population size of ruminal methanogens.  相似文献   

20.
Phylogenetic analysis of conservative nucleotide substitutions in 18 complete sequences of the mitochondrial cytochrome gene of Phocidae (true seals), Odobenidae (walruses), and Otariidae (sea lions and fur seals), plus three ursid and three felid sequences, identified the pinnipeds as monophyletic with Otariidae and Odobenidae on a common evolutionary branch. Analysis of total nucleotide differences separated the evolutionary lineages of northern and southern phocids. Both lineages are distinct from the most ancestral phocid genus, Monachus (monk seals), represented by the Hawaiian monk seal. The inclusion of the Hawaiian monk seal in the subfamily Monachinae makes the subfamily paraphyletic. Among the northern phocids, the hooded seal (genus Cystophora, chromosome number 2n = 34) is sister taxon to the Phoca complex. The Phoca complex, which is characterized by the chromosome number 2n = 32, includes genus Phoca and the monotypic genus Halichoerus (grey seal). The comparison does not support a generic distinction of Halichoerus within the Phoca complex. The present data suggest that Cystophora and Phoca separated 6 million years ago. Among the southern phocids the close molecular relationship of the Weddell and leopard seals relative to their morphological distinction exemplifies rapid adaptation to different ecological niches. This result stands in contrast to the limited morphological differentiation relative to the pronounced molecular distinctions that may occur within the Phoca complex.Correspondence to: Ú. Árnason  相似文献   

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