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21.
This review is based on a study commissioned by the European Commission on the evaluation of scientific, technical and institutional challenges, priorities and bottlenecks for biotechnologies and regional harmonisation of biosafety in Africa. Biotechnology was considered within four domains: agricultural biotechnologies (‘Green’), industrial biotechnologies and biotechnologies for environmental remediation (‘White’), biotechnologies in aquaculture (‘Blue’) and biotechnologies for healthcare (‘Red’). An important consideration was the decline in partnerships between the EU and developing countries because of the original public antipathy to some green biotechnologies, particularly genetically modified organisms (GMOs) and food from GM crops in Europe. The study focus reported here was West Africa (Ghana, Senegal, Mali and Burkina Faso).The overall conclusion was that whereas high-quality research was proceeding in the countries visited, funding is not sustained and there is little evidence of practical application of biotechnology and benefit to farmers and the wider community. Research and development that was being carried out on genetically modified crop varieties was concentrating on improving food security and therefore unlikely to have significant impact on EU markets and consumers. However, there is much non-controversial green biotechnology such as molecular diagnostics for plant and animal disease and marker-assisted selection for breeding that has great potential application. Regarding white biotechnology, it is currently occupying only a very small industrial niche in West Africa, basically in the sole sector of the production of liquid biofuels (i.e., bio-ethanol) from indigenous and locally planted biomass (very often non-food crops). The presence of diffused small-scale fish production is the basis to develop and apply new (Blue) aquaculture technologies and, where the research conditions and the production sector can permit, to increase this type of production and the economy of this depressed areas. However, the problems bound to environmental protection must not be forgotten; priority should be given to monitor the risks of introduction of foreign species. Red biotechnologies potentially bring a vast domain of powerful tools and processes to achieve better human health, most notably improved diagnostics by molecular techniques, better targeting of pathogens and a better knowledge of their sensitivities to drugs to permit better treatment.Biosafety regulatory frameworks had been initiated in several countries, starting with primary biosafety law. However, disparate attitudes to the purpose of biosafety regulation (e.g., fostering informed decision-making versus ‘giving the green-light for a flood of GMOs’) currently prevent a needed consensus for sub-regional harmonisation. To date, most R&D funding has come from North America with some commercial interests from Asia, but African biotechnology workers expressed strong desire for (re-)engagement with interested parties from the European Union. Although in some of the visited countries there are very well qualified personnel in molecular biology and biosafety/regulation, the main message received is that human resources and capacity building in-house are still needed. This could be achieved through home-based courses and capacity-building including funds for post-degree research to motivate and retain trained staff.  相似文献   
22.
The Global Strategy for Plant Conservation has fostered international efforts to achieve its objectives and targets also through capacity building and technology transfer. To this aim, scientific research and activities are among the most suitable means for the implementation of the strategy in developing countries, where the lack of trained people and appropriate facilities contributes, together with an often uncontrolled development and an increasing population, to put species and ecosystems at risk of extinction. In this issue, a collection of contributions discussing theoretical issues and presenting innovative methods of investigation and practical questions related to plant ecology and conservation is presented for sharing experiences and stimulating new initiatives.  相似文献   
23.
We investigated the effects of caffeine mouth rinse on endurance performance, muscle recruitment (i.e., electromyographic activity of the vastus lateralis and rectus femoris), rating of perceived effort and heart rate. Twelve physically-active healthy men cycled at 80% of their respiratory compensation point until task failure. The participants rinsed their mouths for 10 seconds with placebo (PLA, 25 mL of a solution composed of non-caloric mint essence) or caffeine (CAF, 25 mL of 1.2% of anhydrous caffeine concentration with non-caloric mint essence) every 15 minutes of exercise. Time until exhaustion increased 17% (effect size = 0.70) in CAF compared to PLA (p = 0.04). The wavebands of low-frequency electromyographic activity (EMG) of the vastus lateralis and rectus femoris was lower in CAF group than PLA at 50% of the time until exhaustion (p = 0.04). The global EMG signal was lower in CAF group than PLA at 100% of the time until exhaustion (p = 0.001). The rating of perceived effort pooled was higher in CAF mouth rinse (p = 0.001) than PLA group. No effect was found on the heart rate between the groups (p > 0.05). Caffeine mouth rinse increases endurance performance, rating of perceived effort and decreases muscle activity during a moderate-intensity exercise.  相似文献   
24.
Sheep and goat farming is a major source of income in the rural areas of Al-Wadiah in Najran region of Southern Saudi Arabia. The study aims to identify the factors and parameters that influence gender participation in sheep and goat farming. Data were collected by interviewing 167 high school students, including 70 male and 97 female students, in Al-Wadiah, by using the simple random sampling technique. Data were statistically analyzed to establish the relationship between gender and participation in sheep and goat farming. The study revealed significant differences between the two genders, for instance, male herders were more experienced, received more benefits, showed greater interest in discussions on topics related to sheep and goat farming, followed information from TV and radio, and received more services offered by veterinary clinics, which proved more beneficial for them. On the other hand, female herders received fewer services, and the veterinary clinics proved less beneficial for them. However, the correlation between the participation of both genders in sheep and goats management was non-significant toward the statement “feeling ashamed of participating in sheep and goat farming.” Generally, sheep and goat rearing proves more beneficial for male participants than female participants, owing to their greater experience and interest in livestock farming. Moreover, they receive more benefits from TV, radio and veterinary clinics to maintain better health of their livestock. Both male and female herders contribute equally to sheep and goat farming by limiting the time spent on their daily routine. This study would enable policymakers and planners to develop more strategies and extension education programs to overcome the identified barriers and improve the livelihood of herders through their enhanced participation in remote areas.  相似文献   
25.
Several recent contributions to this Journal have reflected on the current usage and understanding of the term acclimation [Bowler, 2005. Acclimation, heat shock and hardening. J. Therm. Biol. 30, 125–130; Loeschcke and Sφrensen, 2005. Acclimation, heat shock and hardening—a response from evolutionary biology. J Therm. Biol. 30, 255–257; Sinclair and Roberts, 2005. Acclimation, shock and hardening in the cold. J. Therm. Biol. 30, 557–562]. As a contribution to this discourse I propose that a look back into the introduction of this term may provide a useful additional insight.  相似文献   
26.
We studied enzymatic adipyl-7-ADCA hydrolysis as a new process for the production of 7-aminodeacetoxycephalosporanic acid (7-ADCA), one of the building blocks for cephalosporin antibiotics like cephalexin and cefadroxil. Adipyl-7-ADCA hydrolysis carried out with immobilised glutaryl acylase was considerably enhanced by addition of phenylglycine amide, the side-chain donor used for cephalexin synthesis; unlike reactions carried out with free enzyme. The rate enhancing effect was not specifically related to phenylglycine amide; we found a linear relationship between the reaction rate and the buffering capacity of the added substance. These observations can be explained by a pH-gradient in the immobilised enzyme, the pH inside the particle being lower (corresponding to low enzyme activity) than outside. It was concluded that the buffer reduced the pH-gradient inside the biocatalyst, and therewith, caused the reaction rate enhancing effects. Further, chloride ions decreased the reaction rate strongly, while sodium, magnesium, sulphate, and potassium did not influence the reaction rate much. For an actual process, it is important to use a buffer that is appropriate for the reaction-pH. In that way the amount of enzyme required in a process can be reduced considerably, in our case a factor of three was found.  相似文献   
27.
<正>Dear Editor,Enterovirus 71(EV71),a member of the genus Enterovirus of the family Picornaviridae,is a single-stranded,positive-sense RNA virus that usually causes mild handfoot-mouth disease(HFMD)in children,with symptoms such as fever,diarrhea,and herpangina(Liu et al.,2013).However,certain strains of EV71 infection can cause severe neurological complications,such as SDLY107(Sun et al.,2014).EV71 is classified into three distinct genotypes(A–C);the B and C genotypes are further divided into B1–B5 and C1–C5 genotypes,respectively,based on  相似文献   
28.
Sulfinpyrazone, a potent uricosuric drug, was tested in vitro for its scavenging action against oxygen free radicals. In this study, sulfinpyrazone was able to scavenge 1,1-diphenyl-2-picrylhydrazyl radical with IC 50 value of 29.82 &#119 g/ml compared to butylated hydroxytoluene (BHT, IC 50 value=20.15 &#119 g/ml) and Trolox (IC 50 value=16.01 &#119 g/ml). It was able to scavenge superoxide anion with IC 50 value of 27.72 &#119 g/ml compared to Trolox (IC 50 value=22.08 &#119 g/ml) and ascorbic acid (IC 50 value=14.65 &#119 g/ml). The hydroxyl radical scavenging activity of sulfinpyrazone is in a concentration-dependent fashion. In the range of concentrations used, sulfinpyrazone was not a scavenger toward H 2 O 2 . However, the intracellular H 2 O 2 -induced 2',7'-dichlorofluorescin diacetate (DCF-DA) fluorescence in HL-60 cells was significantly reduced by sulfinpyrazone during 30-60 min of incubation. Finally, phorbol-12-myristate-13-acetate induced-lucigenin chemiluminescence in whole blood was markedly inhibited by sulfinpyrazone. Our results suggest a new direction for the pharmacological actions of sulfinpyrazone in free radical scavenging properties.  相似文献   
29.
This study aimed to identify some socioeconomic factors affecting local people in central Riyadh area for the utilization of wood and other energy sources in cooking and heating in order to develop some recommendations for conserving woodlands. The study results revealed that gas is the most common energy source used for cooking with a mean usage level of 2.79 (SD = 0.58). On the other hand, wood ranked first for heating with the highest mean, usage level of 1.90 (SD = 1.06). However, electricity and gas as sources of energy for heating ranked second and third with mean usage level of 1.81 and 0.80 respectively. The study revealed that local people with the university education were significantly making higher use of electricity for both cooking and heating and those with no formal education ranked the highest on wood use for both cooking and heating. In addition, those living in traditional houses significantly used more wood for cooking than those living in villas and apartments. Also, local people with high income levels significantly were using more electricity for heating than others. The study recommended conducting extension and environmental awareness raising programs to enhance local residents’ adoption of wood substitutes, promoting employment opportunities for unemployed locals, and subsidizing prices of alternative energy sources.  相似文献   
30.
Some fossil wooden samples of the Tertiary period, extracted from the crater of the kimberlite BHP-Panda pipe from the Lac de Gras region (in the Canadian sub-Arctic area), and previously identified as Sequioxylon canadense Blokhina, were chemically examined to both assess their state of preservation and discuss about the possible causes of their decay. The chemical composition of fossils (in terms of holocellulose, lignin and ash amounts) was evaluated by means of wet analyses, together with the chromatographic analysis of dichloromethane extracts, and additionally measurements of the cation exchange capacity (CEC) of fossils were also carried out. The analyses revealed the complete loss of holocellulose (except for 2 out of 9 samples), whereas lignin became the predominant component, together with ash (whose amount in one case was as high as 47.5%). Moreover, CEC data showed that all acid carboxyls were transformed into carboxylates. They represented the most important form of residual carboxyl groups in the fossils, and were even more abundant than in the reference (fresh) wood. All these occurrences evidenced a generally high level of decay for the fossils, as a consequence of water leaching during burial, which determined both the hydrolysis of esters groups and the partial depolymerisation of lignin.  相似文献   
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