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1.
2.
Jürgen Schultze-Motel 《Vegetation History and Archaeobotany》1994,3(1):33-61
A total of 422 publications from 1991 and 1992 on archaeological remains of cultivated plants have been collected. A list is given of the finds according to species, country and age. 相似文献
3.
Different CMS sources found in Beta vulgaris ssp maritima: mitochondrial variability in wild populations revealed by a rapid screening procedure 总被引:1,自引:0,他引:1
P. Saumitou-Laprade G. J. A. Rouwendal J. Cuguen F. A. Krens G. Michaelis 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,85(5):529-535
Summary Mitochondrial DNA (mtDNA) variation in natural Beta maritima populations has been characterized by way of Southern blot hybridizations of total DNA using non-radioactive probes and chemiluminescent detection. It was found that the previously described N (normal) mitochondrial type could be subdivided into three subtypes. A new mitochondrial genotype (type R) was distinguished in addition to the previously described type S. Both are male-sterile cytoplasms and can produce a. segregation of sexual phenotypes in their progenies depending on the nuclear background. The populations contained at least two to four different mitochondrial genotypes. 相似文献
4.
C. Brombacher 《Vegetation History and Archaeobotany》1997,6(3):167-186
This paper describes the results of the archaeobotanical examination of four Late Neolithic lakeshore settlements on Lake
Biel in Switzerland. Due to the excellent preservation conditions in lakeshore settlements, non-carbonized as well as carbonized
seeds and fruits were recovered in large numbers. In addition to the diaspore analyses, some samples of charcoal and moss
were identified. The spectrum of cultivated plants was markedly different between the sites. In the transition from the 34th
to 33rd century B.C. (sites Nidau, Lüscherz and Lattrigen ‘VI’) naked wheat and barley were predominant, while in the 32nd
century B.C. (Lattrigen'VII') emmer (a glume wheat) was most abundant. Flax and opium poppy were of great importance during
the whole late Neolithic period. In addition to cereals, a large number of cereal weeds were detected. The wild flora included
a high percentage of aquatic and lake-shore plants which results from the strong influence of water on the cultural layers.
Taxa of flood-plain forest are also common. The proportion of potential grassland plants was low (in total only 13 taxa) which
suggests that in addition to the cultivated fields only few pastures and grassland areas existed close to the settlements. 相似文献
5.
Helmut Kroll 《Vegetation History and Archaeobotany》1995,4(1):51-66
Publications on archaeological remains of cultivated plants have been collected, mainly from 1992 and 1993, with some earlier and later ones. A list is given of the finds according to taxon, country, site and age. 相似文献
6.
The conflict between cultivated land protection and economic development has become increasingly acute in recent years. Despite, intensive researches made on this conflict, little attention has been paid to the spatial correlation of variables. In view of this, the paper introduces the spatial panel regression model to estimate, and test whether the relationship between economic growth and cultivated land conversion conforms to Kuznets curve. Research results show that the area of converted cultivated land in China exhibits strong spatial auto-correlation; the spatial panel model with time effect and fixed effect is more stable and significant than conventional panel mode, and that the relationship between economic growth and cultivated land conversion agrees with the inverted U-shape of Kuznets curve, with inflection point occurring when average per capita GDP reaches ¥31330.93 (calculated at comparable price of 1999). On the basis of analysis, it is suggested that the government, with a view to developing economy alongside protecting cultivated land, should attach more importance to land use and planning in the future, pay more attention to the spatial correlation of cultivated land planning in adjacent areas and make greater efforts to increase the input–output ratio of land. 相似文献
7.
Background
Role of multidrug resistance-1 (MDR-1) gene polymorphisms has not been clarified in nephrotic syndrome (NS). Additionally, researchers studied several genetic polymorphisms to explain their influence on different patients' responses to steroid; however the data were inconsistent. Therefore, we aimed to investigate the association of MDR-1 gene polymorphisms [C1236T, G2677T/A, C3435T] and haplotypes with susceptibility to childhood nephrotic syndrome, and whether they influence steroid response.Methods
We detected MDR-1 gene polymorphisms using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 138 NS patients and 140 age and sex matched healthy children.Results
The frequencies of MDR1 G2677T/A GT, GA, TT + AA genotypes or T allele, MDR1 C3435T TT genotype, and T allele genotype frequencies were significantly increased in NS group. While no significant differences were observed in distributions of C1236T genotypes or allele between NS patients and healthy children. Moreover, steroid non-responder NS patients had significantly higher frequencies of MDR1 G2677T/A GT, GA, and TT + AA genotypes than steroid responsive NS patients. We observed also that NS patients with age less than 6 years old had increased frequencies of MDR1 G2677T/A GT, GA, TT + AA genotypes or T allele MDR1 C3435T CT, TT genotypes and T allele. Interestingly the frequency of the TGC haplotype of MDR1 was lower in the initial steroid responders than in non-responders NS patients. On the contrary, there were no any association between the MDR1 haplotypes with NS susceptibility and they did not influence renal pathological findings.Conclusion
Our data suggested that MDR1 C3435T or G2677T/A gene polymorphisms are risk factors of increased susceptibility, earlier onset of NS, and steroid resistance. 相似文献8.
Ana C. Santos Joana Cunha F. Veiga A. Cordeiro-da-Silva Antonio J. Ribeiro 《Carbohydrate polymers》2013
Alginate-dextran sulfate (ADS) microgel has been used to protect insulin from gastrointestinal attack and as a carrier to promote insulin permeation through intestinal epithelium. The throughput of ADS submicron particles generation by emulsification/internal gelation is limited by its wide size distribution. 相似文献
9.
Application of Hazard Analysis and Critical Control Points (HACCP) to the Cultivation Line of Mushroom and Other Cultivated Edible Fungi 总被引:1,自引:0,他引:1
José E. Pardo Vinícius Reis de Figueirêdo Manuel Álvarez-Ortí Diego C. Zied Jesús A. Peñaranda Eustáquio Souza Dias Arturo Pardo-Giménez 《Indian journal of microbiology》2013,53(3):359-369
The Hazard analysis and critical control points (HACCP) is a preventive system which seeks to ensure food safety and security. It allows product protection and correction of errors, improves the costs derived from quality defects and reduces the final overcontrol. In this paper, the system is applied to the line of cultivation of mushrooms and other edible cultivated fungi. From all stages of the process, only the reception of covering materials (stage 1) and compost (stage 3), the pre-fruiting and induction (step 6) and the harvest (stage 7) have been considered as critical control point (CCP). The main hazards found were the presence of unauthorized phytosanitary products or above the permitted dose (stages 6 and 7), and the presence of pathogenic bacteria (stages 1 and 3) and/or heavy metals (stage 3). The implementation of this knowledge will allow the self-control of their productions based on the system HACCP to any plant dedicated to mushroom or other edible fungi cultivation. 相似文献
10.
Filbert Totsingan Anthony J. Bell Jr 《Protein science : a publication of the Protein Society》2013,22(11):1552-1562
The objective of this study was to evaluate the effects of inserting peptide nucleic acid (PNA) sequences into the protein‐binding surface of an immobilized four‐way junction (4WJ). Here we compare the classic immobile DNA junction, J1, with two PNA containing hybrid junctions (4WJ‐PNA1 and 4WJ‐PNA3). The protein interactions of each 4WJ were evaluated using recombinant high mobility group proteins from rat (HMGB1b and HMGB1b/R26A) and human histone H1. In vitro studies show that both HMG and H1 proteins display high binding affinity toward 4WJ's. A 4WJ can access different conformations depending on ionic environment, most simply interpreted by a two‐state equilibrium between: (i) an open‐x state favored by absence of Mg2+, low salt, and protein binding, and (ii) a compact stacked‐x state favored by Mg2+. 4WJ‐PNA3, like J1, shifts readily from an open to stacked conformation in the presence of Mg+2, while 4WJ‐PNA1 does not. Circular dichroism spectra indicate that HMGB1b recognizes each of the hybrid junctions. H1, however, displays a strong preference for J1 relative to the hybrids. More extensive binding analysis revealed that HMGB1b binds J1 and 4WJ‐PNA3 with nearly identical affinity (KDs) and 4WJ‐PNA1 with two‐fold lower affinity. Thus both the sequence/location of the PNA sequence and the protein determine the structural and protein recognition properties of 4WJs. 相似文献