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Xiaobin Chen Hugo Giambini Ephraim Ben-Abraham Kai-Nan An Ahmad Nassr Chunfeng Zhao 《PloS one》2015,10(10)
IntroductionAn increased bone mineral density (BMD) in the proximity to tendon insertion can improve rotator cuff repair and healing. However, how a decrease of BMD in the humeral head affects the biomechanical properties of the rotator cuff tendon is still unclear. Previous studies have demonstrated ovariectomy in animals to lead to osteoporosis and decreased BMD, and Teriparatide (PTH) administration to improve BMD and strength of bone. This study aimed to explore the correlation between humeral head BMD and infraspinatus (ISP) tendon insertion strength, and if an increase in bone quantity of the humeral head can improve the strength of the rotator cuff.ResultsSignificant differences were observed in the measured humeral head BMD of the Control and OVX-PTH groups compared to the OVX-Saline group (P = 0.0004 and P = 0.0024, respectively). No significant difference was found in failure stress among the three groups, but an expected trend with the control group and OVX-PTH group presenting higher failure strength compared to the OVX-Saline group. BMD at the humeral head showed a positive linear correlation with stress (r2 = 0.54). Histology results showed the superiority in OVX-PTH group ISP enthesis compared to the OVX-Saline group.ConclusionBone loss of the humeral head leads to decreased tendon/bone insertion strength of the infraspinatus tendon enthesis. Teriparatide administration can increase bone density of the humeral head and may improve the mechanical properties of the infraspinatus tendon enthesis. 相似文献
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Jingting Zhang Wei Ren Pingli An Zhihua Pan Liwei Wang Zhiqiang Dong Di He Jia Yang Shufen Pan Hanqin Tian 《PloS one》2015,10(9)
It has long been concerned how crop water use efficiency (WUE) responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation) and agronomic practices (fertilization and cropping patterns) in the semi-arid area of northern China (SAC) during two periods, 1983–1999 and 2000–2010 (drier and warmer). Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax) in warm-dry environment while reach the stable minimum WUE (WUEmin) in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6–11.0% and 19.5–92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping). Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming. 相似文献
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We cloned and sequenced a plant cDNA that encodes U1 small nuclear ribonucleoprotein (snRNP) 70K protein. The plant U1 snRNP 70K protein cDNA is not full length and lacks the coding region for 68 amino acids in the amino-terminal region as compared to human U1 snRNP 70K protein. Comparison of the deduced amino acid sequence of the plant U1 snRNP 70K protein with the amino acid sequence of animal and yeast U1 snRNP 70K protein showed a high degree of homology. The plant U1 snRNP 70K protein is more closely related to the human counter part than to the yeast 70K protein. The carboxy-terminal half is less well conserved but, like the vertebrate 70K proteins, is rich in charged amino acids. Northern analysis with the RNA isolated from different parts of the plant indicates that the snRNP 70K gene is expressed in all of the parts tested. Southern blotting of genomic DNA using the cDNA indicates that the U1 snRNP 70K protein is coded by a single gene. 相似文献
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Extracellular release of photosynthetic products by freshwater phytoplankton populations, with special reference to the algal species involved 总被引:3,自引:0,他引:3
SUMMARY. Over three successive years, depth profiles of C-fixation and excretion, chlorophyll- a concentrations, phytoplankton species composition and bacterial numbers were determined in Lake Vechten, a slightly eutrophic lake in The Netherlands. Special attention was given to the method used to measure extracellular release.
Excretion of dissolved organic14 C depended largely upon the photo-synthetic activity of the phytoplankton, ranging from 0–2.5 mg m-1 h-1 , representing a percentage extracellular release (PER) of 0–25%.
During a period in August, however, a subsurface chlorophyll- a maximum at 5–7 m depth coincided with high excretion rates of up to 10 mg Cm-3 h-1 (PER = 55%). Phytoplankton analysis revealed a stratification in numbers of Mallomonas caudata with a maximum at 5–7 m depth.
The results suggest that in these water layers bacterial populations grew at the expense of the dissolved organic carbon compounds excreted by Mallomonas caudata. This means that extracellular release can temporarily function as an important nutrient source for the heterotrophie community in addition to the more or less constant dissolved organic carbon pool. 相似文献
Excretion of dissolved organic
During a period in August, however, a subsurface chlorophyll- a maximum at 5–7 m depth coincided with high excretion rates of up to 10 mg Cm
The results suggest that in these water layers bacterial populations grew at the expense of the dissolved organic carbon compounds excreted by Mallomonas caudata. This means that extracellular release can temporarily function as an important nutrient source for the heterotrophie community in addition to the more or less constant dissolved organic carbon pool. 相似文献
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Sucrose phosphorylase is an interesting biocatalyst that can glycosylate a variety of small molecules using sucrose as a cheap but efficient donor substrate. The low thermostability of the enzyme, however, limits its industrial applications, as these are preferably performed at 60°C to avoid microbial contamination. Cross-linked enzyme aggregates (CLEAs) of the sucrose phosphorylase from Bifidobacterium adolescentis were found to have a temperature optimum that is 17°C higher than that of the soluble enzyme. Furthermore, the immobilized enzyme displays an exceptional thermostability, retaining all of its activity after 1 week incubation at 60°C. Recycling of the biocatalyst allows its use in at least ten consecutive reactions, which should dramatically increase the commercial potential of its glycosylating activity. 相似文献
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Using standardized conditions, 65 genotypes of Gladiolus were screened for Fusarium resistance. High levels were found in 'large-flowered" types, Primulinus hybrids, G. callianthus, G. garnierii , and G. dalenii. Some accessions of G. dalenii exhibited no disease symptoms when inoculated with two standard test isolates. No resistance was found in 'small-flowered' types. To estimate race-specifity of the resistance, eight highly resistant Gladiolus genotypes were tested in an in vitro test against 43 isolates of F. oxysporum f.sp. gladioli. Two isolates were able to partially infect the G. dalenii accessions and this was confirmed using whole plants. Implications for resistance breeding are discussed. 相似文献
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