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91.
92.
Thirteen sets of monozygotic (MZ) twins from an extended multi-generation family are reported. Zygosity was determined by interviewing families for overall physical similarity and by assessment of facial photographs. A hypothetical gene was traced back five generations to a common grandfather. Familial monozygotic twinning in this pedigree is compatible with autosomal dominant inheritance with reduced penetrance. Other plausible mechanisms of inheritance are discussed. 相似文献
93.
Three major peroxidases, designated as A, B2 and B2 from Solanum melongena leaves have been reported. Peroxidases-A, -B2 and -B2 were considered to be true peroxidases on the basis of k1:k4 ratio. The pH optima for the three enzymes were found to be 7·0, 6·0 and 6.0 respectively. These peroxidases differ in their k1:k4 ratio, in the effect of pH on this ratio and in the uric acid/guaiacol and o-dianisidine/guaiacol activity ratio. 相似文献
94.
The present study reports weight-length (W-L) relationships and discusses the relative growth of the banded murex (Hexaplex trunculus) from intertidal and offshore areas of the Gulf of Gabès (southern Tunisia). Overall, 9634 H. trunculus were sampled (6608 from intertidal and 3026 from offshore), with both populations comprising broad ranges in shell length (intertidal: 13.6–78.5 mm; offshore: 22.9–91.1 mm) and total weight (intertidal: 0.2–63.8 g; offshore: 0.6–92.5 g). In both populations, W-L relationships were highly significant and the morphometric parameters were highly correlated (intertidal: r?=?0.967; offshore: r?=?0.973). Relative growth was significantly different between populations, with intertidal H. trunculus displaying a negative allometry (b?=?2.962) and offshore H. trunculus exhibiting isometric growth (b?=?3.013). Factors influencing total weight (soft-body weight and shell weight) and potentially responsible for differences in W-L relationships and relative growth between populations were discussed. In addition, a useful comparative analysis for fisheries biology, assessment and management purposes was performed with analogous information from other populations of H. trunculus from the Mediterranean Sea and the Atlantic Ocean. 相似文献
95.
Imen Mokdad-Bzeouich Nadia Mustapha Aicha Sassi Ahmed Bedoui Mohamed Ghoul Kamel Ghedira Leila Chekir-Ghedira 《Cell stress & chaperones》2016,21(5):773-781
Many studies have been performed to assess the potential utility of natural products as immunomodulatory agents to enhance host responses against infection or to ameliorate immune-based pathologies. To determine whether eriodictyol has immunomodulatory effects and clarify which types of immune effector cells are stimulated in vitro, we investigated the stimulatory effect of eriodictyol on spleen cells isolated from BALB/c mice. Eriodictyol significantly stimulated splenocyte proliferation. However, only B lymphocytes (not T lymphocytes) could be stimulated by eriodictyol in a dose-related manner. Studies assessing potential effect of eriodictyol on innate immunity reported that eriodictyol enhanced significantly the killing activity of natural killer (NK) cells, T lymphocytes, and macrophages. We also demonstrated that eriodictyol inhibited nitric oxide (NO) production and lysosomal enzyme activity in murine peritoneal macrophages cultured ex-vivo, suggesting a potential anti-inflammatory effect in situ. Eriodictyol revealed also a cellular anti-oxidant activity in splenocytes and macrophages. Furthermore, eriodictyol increased catalase activity in spleen cells. From this data, it can be concluded that eriodictyol exhibited an immunomodulatory effect that could be ascribed in part to a cytoprotective effect related to its anti-oxidant activity. 相似文献
96.
97.
Sherihan El-sayed Kamel Metwally Abdalla A. El-Shanawani Lobna M. Abdel-Aziz Ahmed A. El-Rashedy Mahmoud E.S. Soliman Luca Quattrini Vito Coviello Concettina la Motta 《Bioorganic & medicinal chemistry letters》2017,27(20):4760-4764
A series of quinazolinone-based rhodanine-3-acetic acids was synthesized and tested for in vitro aldose reductase inhibitory activity. All the target compounds displayed nanomolar activity against the target enzyme. Compounds 3a, 3b, and 3e exhibited almost 3-fold higher activity as compared to the only marketed reference drug epalrestat. Structure-activity relationship studies indicated that bulky substituents at the 3-phenyl ring of the quinazolinone moiety are generally not tolerated in the active site of the enzyme. Insertion of a methoxy group on the central benzylidene ring was found to have a variable effect on ALR-2 activity depending on the nature of peripheral quinazolinone ring substituents. Removal of the acetic acid moiety led to inactive or weakly active target compounds. Docking and molecular dynamic simulations of the most active rhodanine-3-acetic acid derivatives were also carried out, to provide the basis for further structure-guided design of novel inhibitors. 相似文献
98.
Potato bacterial wilt suppression and plant health improvement after application of different antioxidants 下载免费PDF全文
Shahenda M. A. Farag Kamel M.A. Elhalag Mohamed H. Hagag Abdel Salam M. Khairy Heba M. Ibrahim Moheb T. Saker Nevein A. S. Messiha 《Journal of Phytopathology》2017,165(7-8):522-537
Bacterial wilt caused by Ralstonia solanacearum is a devastating disease that often threatens potato production and exportation. The potential of four antioxidants (seaweed extract (SWE), yeast, chitosan and ascorbic acid (ASA)) in controlling the disease was evaluated in vitro, under glasshouse and field conditions. The field experiment was conducted in two naturally infested locations: Wardan, Giza (sandy soil), and Talia, Minufiya (silty clay soil). Only chitosan showed antibacterial properties against the pathogen in vitro. SWE, yeast and chitosan showed disease suppression under both glasshouse and field conditions. The disease suppression was accompanied by an increase in the ratio of soil copiotrophic to oligotrophic bacteria. The three antioxidants increased plant nitrogen content, decreased soil OM content and decreased C/N ratio. Disease suppression after chitosan application was clearly observed only in Wardan area, which was characterized by a higher soil alkalinity. A high percentage of antagonistic fluorescent strains similar to Pseudomonas putida group were detected for chitosan‐treated plants in Wardan area (sandy soil). ASA drastically decreased the count of the pathogen in soil, but was conducive to the pathogen in plant tissues. A remarkable increase in microbial (bacterial and fungal) soil and rhizosphere diversity as indicated by PCR‐DGGE analysis for bacterial 16S rRNA and fungal 18S rRNA was recorded. In Talia area (silty clay soil), the soil microbial community was more stable and was in general resistant to the disease where the soils were characterized by high electrical conductivity. SWE, yeast and ASA significantly increased crop production in Talia area only. 相似文献
99.
Mabrouk SB Messaoud EB Ayadi D Jemli S Roy A Mezghani M Bejar S 《Molecular biotechnology》2008,38(3):211-219
A gene encoding maltogenic amylase from acidic Bacillus sp. US149 (maUS149) was cloned, sequenced and over-expressed in Escherichia coli. The nucleotide sequence analysis revealed an open reading frame (ORF) of 1749 bp encoding a protein of 582 residues. The
alignment of deduced amino acid sequence revealed a relatively low homology with the already reported maltogenic amylases.
In fact, its highest identity, of only 60%, was found with the maltogenic amylase of Thermus sp. IM6501. The recombinant enzyme (MAUS149) was found to be intracellular and was purified to homogeneity from the cell
crude extract with a yield of 23%. According to PAGE analysis, under reducing and non-reducing conditions, the recombinant
enzyme has an apparent molecular weight of 135 kDa and is composed of two identical subunits of 67.5 kDa each. The maximum
activity was obtained at 40°C and pH 6.5. MAUS149 could be classified as a maltogenic amylase since it produces mainly maltose
from starch, maltose and glucose from β-cyclodextrin, and panose from pullulan. 相似文献
100.