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1.
This communication describes a short routine in BASICA for theIBM-PC, written to collect data from a Beckman liquid scintillationcounter. In the form presented here the routine converts incomingbytes into separate lines and saves these lines in a file. Thereare many possible applications for further use of the data inthese files. A few suggestions are given as to the format inwhich data can be stored and how to process these data automaticallyafter all samples have been counted. The only hardware neededis an asynchronous communications adapter for the IBM-PC andan RS232 cable. Received on July 27, 1985; accepted on August 2, 1985  相似文献   
2.
In studying inhibitors and activators of enzymes it has often been found that inhibitors act as activators when in very low concentrations and that certain activators (in suitable concentrations) show inhibition. Similar results were obtained in the present work in studying urease from soya bean in the presence of lead acetate. Lead acetate is normally an inhibitor of urease. It was found, however, that in small concentrations of lead acetate increase in the activity of urease occurs. On prolonging the time of the reaction inhibition develops and still later increased enzymatic activity again occurs. The results were elaborated statistically and are discussed in relation to the use of “adaptation” of urease in unfavourable conditions in reaction mixtures by the action of lead acetate.  相似文献   
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The recovery of soil derived nitrogen (NDFS) and fertilizer N (NDFF) was investigated in highland rice (Oryza sativa L.) fields in Bhutan, characterized by high inputs of farmyard manure (FYM). The effect of 60 kg N ha?1 (60 N) applied in two splits to a traditional and an improved cultivar, popular among the farmers, was investigated using the 15N isotope dilution technique. No differences were found between cultivars with respect to the uptake of NDFS and NDFF, but the improved cultivar yielded 27% more (P?≤?0.05) grain compared with the traditional cultivar. This was largely due to its greater harvest index (HI). The mean percentage recovery of fertilizer N (REN) applied at 45 days after transplanting (DAT) was 34% compared to 22% at 7 DAT, resulting in 56% greater uptake of NDFF at 45 DAT. The overall REN for both the improved and the traditional cultivars were 25.7% and 30% respectively, with no difference between cultivars, but REN decreased with increasing FYM inputs. Fertilizer N recommendations that allow for previous FYM inputs combined with applications timed to coincide with maximum crop demand (45 DAT), and the use of improved cultivars, could enhance N fertilizer recoveries (REN) and increase rice yields in the Bhutan Highlands.  相似文献   
6.

Background

Each year, thousands of pilgrims travel to the Janai Purnima festival in Gosainkunda, Nepal (4380 m), ascending rapidly and often without the aid of pharmaceutical prophylaxis.

Methods

During the 2012 Janai Purnima festival, 538 subjects were recruited in Dhunche (1950 m) before ascending to Gosainkunda. Through interviews, subjects provided demographic information, ratings of AMS symptoms (Lake Louise Scores; LLS), ascent profiles, and strategies for prophylaxis.

Results

In the 491 subjects (91% follow-up rate) who were assessed upon arrival at Gosainkunda, the incidence of AMS was 34.0%. AMS was more common in females than in males (RR = 1.57; 95% CI = 1.23, 2.00), and the AMS incidence was greater in subjects >35 years compared to subjects ≤35 years (RR = 1.63; 95% CI = 1.36, 1.95). There was a greater incidence of AMS in subjects who chose to use garlic as a prophylactic compared to those who did not (RR = 1.69; 95% CI = 1.26, 2.28). Although the LLS of brothers had a moderate correlation (intraclass correlation = 0.40, p = 0.023), sibling AMS status was a weak predictor of AMS.

Conclusions

The incidence of AMS upon reaching 4380 m was 34% in a large population of Nepalese pilgrims. Sex, age, and ascent rate were significant factors in the development of AMS, and traditional Nepalese remedies were ineffective in the prevention of AMS.  相似文献   
7.
Helopeltis theivora Waterhouse (Heteroptera: Miridae), is a major sucking pest of tea in North East India along with other tea growing countries. In West Bengal, tea is cultivated in three sub-Himalayan regions, Terai (foothill plains western to river Teesta), the Dooars (foothill plains eastern to river Teesta) and the Darjeeling hill slopes. Most plantations, in these regions are managed conventionally i.e. by spraying different synthetic insecticides and a few by organic farming using different herbal and microbial insecticides. In conventional plantations, continuous application of insecticides may lead to the selection of more tolerant H. theivora populations making the pest difficult to control. So, there is a pressing need to know the biochemical variability in relation to the metabolic resistance in the pest populations and develop a population specific control strategy. Activity of three principal insecticide detoxifying enzymes in H. theivora populations were studied from three tea growing regions of North Bengal. Higher levels of activity of all the studied enzymes were found from conventional tea plantations. In male H. theivora, the activity of general esterases (GEs) was 6.6–11.2 and 10.5–11.4 fold higher, cytochrome P450 (CYPs) was 2.0–3.2 and 3.0–3.2 fold higher and glutathione S-transferase (GSTs) was 5.2–8.3 and 6.4–8.7 fold higher in Terai and the Dooars populations, respectively than organic populations from Darjeeling hill slopes. Similarly, in female H. theivora, activity of GEs was 6.2–10.3 and 8.3–9.6 folds higher, CYPs was 1.9–3.2 and 3.0–3.3 fold, and GSTs was 3.5–5.4 and 4.4–6.0 fold higher in Terai and the Dooars, respectively than the organic populations from Darjeeling hill slopes. The activities of all three enzymes were found to be significantly low in organic plantations from Darjeeling hill slopes. Esterase I–VI isozymes with higher level of expression were found in specimens from conventional tea plantations than organic populations of H. theivora from Darjeeling hill slopes in isozymes study.  相似文献   
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Understanding factors determining the distribution of species is a key requirement for protecting diversity in a specific area. The aim of this study was to explore the factors affecting diversity and distribution of species of birds on different forested hills in central Nepal. The area is rich in species of birds. Because the area is characterized by steep gradients, we were also interested in the importance of altitude in determining the diversity and species composition of the bird communities. We assessed bird diversity and species composition based on point observations along a gradient of increasing altitude in two valleys (Kathmandu and Palung) in central Nepal. Data on environmental variables were also collected in order to identify the main determinants of bird diversity and species composition of the bird communities. We recorded 6522 individual birds belonging to 146 species, 77 genera and 23 families. Resident birds made up 80% (117 species) of the total dataset. The study supported the original expectation that altitude is a major determinant of species richness and composition of bird communities in the area. More diverse bird communities were found also in areas with steeper slopes. This together with the positive effect of greater heterogeneity suggests that forests on steep slopes intermixed with patches of open habitats on shallow soil at large spatial scales are more important for diverse bird communities than more disturbed habitats on shallow slopes. In addition, we demonstrated that while different habitat characteristics such as presence of forests edges and shrubs play an important role in driving species composition, but they do not affect species richness. This indicates that while habitat conditions are important determinants of the distribution of specific species, the number of niches is determined by large scale characteristics, such as landscape level habitat heterogeneity and altitude. Thus, to protect bird diversity in the mid-hills of central Nepal, we should maintain diverse local habitats (viz. forest, shrubs, open land, etc.) but also make sure the natural habitats on steeper slopes with large scale heterogeneity are maintained.  相似文献   
10.
The 26S proteasome is a multi‐catalytic ATP‐dependent protease complex that recognizes and cleaves damaged or misfolded proteins to maintain cellular homeostasis. The 26S subunit consists of 20S core and 19S regulatory particles. 20S core particle consists of a stack of heptameric alpha and beta subunits. To elucidate the structure‐function relationship, we have dissected protein‐protein interfaces of 20S core particle and analyzed structural and physiochemical properties of intra‐alpha, intra‐beta, inter‐beta, and alpha‐beta interfaces. Furthermore, we have studied the evolutionary conservation of 20S core particle. We find the size of intra‐alpha interfaces is significantly larger and is more hydrophobic compared with other interfaces. Inter‐beta interfaces are well packed, more polar, and have higher salt‐bridge density than other interfaces. In proteasome assembly, residues in beta subunits are better conserved than alpha subunits, while multi‐interface residues are the most conserved. Among all the residues at the interfaces of both alpha and beta subunits, Gly is highly conserved. The largest size of intra‐alpha interfaces complies with the hypothesis that large interfaces form first during the 20S assembly. The tight packing of inter‐beta interfaces makes the core particle impenetrable from outer wall of the cylinder. Comparing the three domains, eukaryotes have large and well‐packed interfaces followed by archaea and bacteria. Our findings provide a structural basis of assembly of 20S core particle in all the three domains of life.  相似文献   
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