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311.
M. S. Islam A. Siddika M. N. H. Khan M. M. Goldar M. A. Sadique A. N. M. H. Kabir Anwar Huq R. R. Colwell 《Applied microbiology》2001,67(7):3328-3330
Five tube-wells in Matlab, Bangladesh, were selected for analysis of selected biophysicochemical parameters. The results showed that all tube-well water samples contained zooplankton and bacteria. Results for some of the parameters were outside the accepted limits recommended by the World Health Organization for drinking water. It is concluded that water from tube-wells should be treated if used as drinking water. 相似文献
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It has proposed that hexokinase bound to mitochondria occupies a preferred site to wich ATP from oxidative phosphorylation is channeled directly (Bessman, S. (1966) Am. J. Medicine 40, 740–749). We have investigated this problem in isolated Zajdela hepatoma mitochondria. Addition of ADP to well-coupled mitochondria in the presence of an oxidizable substrate initiates the synthesis of glucose 6-phosphate via bound hexokinase. This reaction is only partially inhibited by oligomycin, carboxyatractyloside, carbonyl cyanide m-chlorophenylhydrazone (CCCP) ot any combination of these, suggesting a source of ATP in addition to oxidative phosphorylation. This source appears to be adenylate kinase, since Ado2P5, an inhibitor of the enzyme, suppresses hexokinase activity by about 50% when added alone or suppresses activity completely when added together with any of the inhibitors of oxidative phosphorylation. Ado2P5 does not uncouple oxidative phosphorylation nor does it inhibit ADP transport (state 3 respiration) or hexokinase. The relative amount of ATP contributed by adenylate kinase is dependent upon the ADP concentration. At low ADP concentraions, glucose phosphorylation is supported by oxidative phosphorylation, but as the adenine nucleotide translocator becomes saturated the ATP contributed by adenylate kinase increases due to the higher apparent Km of the enzyme. Under conditions of our standard experiment ([ADP] = 0.5 mM), adenylate kinase provides about 50% of the ATP used by hexokinase in well-coupled mitochondria. In spite of this, externally added ATP supported higher rates of hexokinase activity than ADP. Our findings demonstrate that oxidative phosphorylation is not a specific or preferential source of ATP for hexokinase bound to hepatoma mitochondria. The apparent lack of a channeling mechanism for ATP to hexokinase in these mitochondria is discussed. 相似文献
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315.
Cheng Gao Nan-Nan Shi Yue-Xing Liu Kabir G. Peay Yong Zheng Qiong Ding Xiang-Cheng Mi Ke-Ping Ma Tesfaye Wubet François Buscot Liang-Dong Guo 《Molecular ecology》2013,22(12):3403-3414
Microbial diversity is generally far higher than plant diversity, but the relationship between microbial diversity and plant diversity remains enigmatic. To shed light on this problem, we examined the diversity of a key guild of root-associated microbes, that is, ectomycorrhizal (EM) fungi along a plant diversity gradient in a Chinese subtropical forest. The results indicated that EM fungal diversity was positively correlated with host plant diversity. Furthermore, this relationship was best predicted by host genus-level diversity, rather than species-level diversity or family-level diversity. The generality of this finding was extended beyond our study system through the analyses of 100 additional studies of EM fungal communities from tropical and temperate forests. Here as well, EM fungal lineage composition was significantly affected by EM plant diversity levels, and some EM fungal lineages were co-associated with some host plant genera. These results suggest a general diversity maintenance mechanism for host-specific microbes based on higher order host plant phylogenetic diversity. 相似文献
316.
D J El Kabir 《BMJ (Clinical research ed.)》1982,284(6314):480-481
317.
Kabir G. Peay Ian A. Dickie David A. Wardle Peter J. Bellingham Tadashi Fukami 《Oikos》2013,122(2):258-264
Introduced animals can indirectly affect decomposers through trophic cascades and habitat modifications, but whether their effects are strong enough to influence both the structure and function of decomposer communities remains unclear. We conducted an experiment on rat‐invaded and rat‐free islands off the coast of New Zealand to determine whether introduced rats affected the structure and function of wood‐decomposing fungi. Gamma‐irradiated branch segments from a single tree were placed on the forest floor on nine rat‐invaded and nine rat‐free islands, and fungal community structure and wood decomposition rates measured after two years of in situ decomposition. We found significant differences in fungal community structure in the wood between rat‐invaded and rat‐free islands. Furthermore, there was a significant correlation between fungal community structure and wood decomposition rate on rat‐free islands but not on rat‐invaded islands, because of decreased variability in decomposition rates on invaded islands. Despite these differences between rat‐free and rat‐invaded islands, mean decomposition rates were indistinguishable between the two sets of islands. These results suggest that there may be a great deal of functional redundancy in fungal communities and that removing rats from islands could reverse the rat‐induced changes that we observed in the relationship between the structure and function of decomposer communities. 相似文献
318.
ABSTRACT: INTRODUCTION: ITN use is generally poor in Nigeria among all categories of people. Although use of ITNs has been shown to reduce malarial morbidity and mortality, this measure needs to be supported by an adequate healthcare system providing ITN possibly at the household level. This study was therefore designed to determine the effect of health education on the uptake of ITN among nursing mothers in rural communities in Nigeria. METHODS: The study design was a quasi-experimental study carried out in Ijebu North Local Government Area of Ogun State. A multistage random sampling technique was used in choosing the required samples for this study and a semi- structured questionnaire was used to collect relevant information. The intervention consisted of a structured educational programme based on a course content adapted from the national malaria control programme. A total of 400 respondents were recruited into the study with 200 each in both the experimental and control groups and were followed up for a period of 3 months when the knowledge and uptake of ITN was reassessed.ResultThere was no significant difference (P >0.05) observed between the experimental and control groups in terms of socio-dermographic characteristics such as age, marital status, religion, and income. The ITN ever users in experimental group were 59 [29.5%] and 138 [72.6%] in pre and post intervention period, respectively (p value =0.0001). These proportions of ITN ever users were 55 [27.5%] and 57 [31.6%] in control group, during the pre and post intervention periods (p = 0.37). Post health education intervention, degree of change in knowledge of ITN re-treatment [37.0%] and mounting [33.5%], readiness to use if given free [30.5%] and belief in efficacy [36.9%] improved significantly in the experimental group while there was no significant change in the control group [p = 0.84, 0.51, 0.68 &0.69 respectively]. Majority [89%] of the respondents were willing to buy ITN for between US$ 1.5 to US$ 3.0. There was no statistically significant change (P >0.05) despite intervention in the amount the respondents were willing to pay to own an ITN in both the experimental and control groups. CONCLUSION: The study concludes that the use of ITN in the study population was significantly increase by health education and that the free distribution of ITN may not guarantee its use. Uptake of ITN can be significantly improved in rural areas if the nets are made available and backed up with appropriate health education intervention. 相似文献