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41.
Samia Dabbou Imed Rjiba Adel Echbili Noureddine Gazzah Beligh Mechri Mohamed Hammami 《化学与生物多样性》2010,7(7):1801-1813
Our study reports the triglyceride (triacylglycerol, TAG) composition of five new Tunisian virgin olive oil cultivars obtained through controlled crossings of the cultivar (cv.) Chemlali Sfax. These cultivars have been selected among a progeny of 500 olive descendants, based on an evaluation of the fatty‐acid (FA) composition of their oils. Among these samples, two were derived from the crossing with the cv. Sigoise as pollinator (SM634) or pollen acceptor (SM1110) and the others from the crossing with the cv. Meski as pollen acceptor (SM513, SM514, and SM517). The five descendants were characterized by a good fat value, a balanced FA composition, and a high content of triolein, varying between 26.9 (SM514) and 45.46% (SM1110). They had an improved FA composition as compared to that of the cv. Chemlali Sfax and their fruits were slightly bigger. The principal component analysis suggested that the TAG variables were more suitable than the total FAs for an optimum classification of the cultivar samples analyzed. The cultivars obtained through the crossing with the cv. Sigoise (as pollen acceptor or pollinator) had a more favorable composition of FAs and TAG than those obtained through the crossing with the cv. Meski, which indicated that genetic factors had the most important influence on the quality of the virgin olive oils. 相似文献
42.
Bouskila M Hunter RW Ibrahim AF Delattre L Peggie M van Diepen JA Voshol PJ Jensen J Sakamoto K 《Cell metabolism》2010,12(5):456-466
Glycogen synthase (GS), a key enzyme in glycogen synthesis, is activated by the allosteric stimulator glucose-6-phosphate (G6P) and by dephosphorylation through inactivation of GS kinase-3 with insulin. The relative importance of these two regulatory mechanisms in controlling GS is not established, mainly due to the complex interplay between multiple phosphorylation sites and allosteric effectors. Here we identify a residue that plays an important role in the allosteric activation of GS by G6P. We generated knockin mice in which wild-type muscle GS was replaced by a mutant that could not be activated by G6P but could still be activated normally by dephosphorylation. We demonstrate that knockin mice expressing the G6P-insensitive mutant display an ~80% reduced muscle glycogen synthesis by insulin and markedly reduced glycogen levels. Our study provides genetic evidence that allosteric activation of GS is the primary mechanism by which insulin promotes muscle glycogen accumulation in?vivo. 相似文献
43.
Citrus Tristeza Virus (CTV), usually occurs in nature as a mixture of genotypes. Six naturally infected citrus
(Citrus sinensis) trees grafted on sour orange rootstock were collected from three citrus growing governorates
in Egypt (Sharqia, Qalyubia and Garbia). In this study, RT-PCR, Single-Strand Conformation Polymorphism
(SSCP) and nucleotide sequence analysis were used for four independent CTV genomic regions (p65, p18,
p20, and p23) to detect and assess the sequence and genetic variabilities among CTV Egyptian isolates. RTPCR products (650 bp) for the CTV p23 gene obtained from the selected isolates were used for the SSCP analysis
and DNA sequencing. SSCP patterns of p23 gene for individual isolates yielded different complex haplotype patterns. Nucleotide sequence analysis of p23 region amplified from six isolates under study revealed that p23 shared
high nucleotide identity 98.7% with T36 isolate from USA, Florida. Phylogenetic analysis of p23 gene indicated a
close evolutionary relationship between all examined isolates and Qaha isolate (T36 isolate group), suggesting that
they may have originated from closely related ancestors. Nucleotide sequence analysis of the three genes located
on CTV 3′-coterminal overhang, p18, p20 and p65, amplified from isolate A3, Sharqia governorate, revealed that
the p18, p65, and p20 genes were related to the T3-KB isolate from South Africa with 99%–100% sequence
homology. Phylogenetic relationship analysis for p65, p18 and p20 ORFs clustered the current A3 isolate with
T3 genotype group. The recombination analysis identified three of six isolates from Sharqia, and Garbia as potential recombinant for p23 gene. The isolates T36 and T3 were identified as major donors for recombination events
in isolate A3. Our results concluded that p23 ORF likely to be as a hotspot region for recombination and originated through recombination event. The current study indicated that recombination is an important factor for the
origin of CTV strains in Egypt. 相似文献
44.
Mounawer Badri Adel Zitoun Houcine Ilahi Thierry Huguet Mohamed Elarbi Aouani 《Journal of genetics》2008,87(3):241-255
Genetic variability in 10 natural Tunisian populations of Medicago laciniata were analysed using 19 quantitative traits and 12 polymorphic microsatellite loci. A large degree of genetic variability
within-populations and among-populations was detected for both quantitative characters and molecular markers. High genetic
differentiation among populations for quantitative traits was seen, with Q
ST
= 0.47, and F
ST
= 0.47 for microsatellite markers. Several quantitative traits displayed no statistical difference in the levels of Q
ST
and F
ST
. Further, significant correlations between quantitative traits and eco-geographical factors suggest that divergence in the
traits among populations may track environmental differences. There was no significant correlation between genetic variability
at quantitative traits and microsatellite markers within populations. The site-of-origin of eco-geographical factors explain
between 18.13% and 23.40% of genetic variance among populations at quantitative traits and microsatellite markers, respectively.
The environmental factors that most influence variation in measured traits among populations are assimilated phosphorus (P205) and mean annual rainfall, followed by climate and soil texture, altitude and organic matter. Significant associations between
eco-geographical factors and gene diversity, H
e
, were established in five-microsatellite loci suggesting that these simple sequence repeats (SSRs) are not necessarily biologically
neutral. 相似文献
45.
The present study aimed to evaluate the association between the environmental tobacco smoke (ETS) and DNA damage in relation to oxidative stress (OS) in children. Sixty-four children of age 1-8 years, selected from the outpatient clinic of Mansoura University Children Hospital were divided into two groups (23 children/group) based on high (>20 cigarettes/day) or low (<20 cigarettes/day) exposure to ETS at home. Twenty symptom-free children with normal cotinine level and with no exposure to ETS were recruited as controls. The comet assay was used to quantify the level of DNA damage in lymphocytes isolated from all children. Spectrophotometric methods were used to assess the serum level of malondialdehyde (MDA) and activity of glutathione peroxidase (GSH-Px) in erythrocytes. Also, serum level of tocopherol fractions (alpha, gamma, delta) was assessed by high performance liquid chromatography (HPLC). Children exposed to ETS exhibited retarded growth, more chest problems, and gastroenteritis than the control. A significant increase in mean comet tail length indicating DNA damage was observed in ETS-exposed children (P<0.001) compared to controls. ETS-exposed children had significantly (P<0.001) higher MDA level paralleled with significant (P<0.001) decrease in the level of GSH-Px and tocopherol fractions compared with controls. The GSH-Px activity and tocopherol levels were inversely correlated with the increase of ETS exposure. These results show that inhalation of ETS is associated with an increase in the level of oxidants and a simultaneous decrease in the level of antioxidants in the children's blood. This status of oxidant-antioxidant imbalance (OS) may be one of the mechanisms leading to DNA damage detected in lymphocytes of ETS-exposed children. In conclusion, the present study gives an indication of an association between DNA damage and ETS exposure in children. 相似文献
46.
47.
A new series of chiral carboxylate-bridged complexes of Mn(II), Co(II), and Ni(II) has been synthesized by reaction of M(II) salts with (S)-2-hydroxy-2-methyl-butanedioic acid ((S)-citramalic acid) under solvothermal conditions. The Mn(II) compound 1 is obtained as a crystalline powder, whereas the Co(II) and Ni(II) compounds (2 and 3 respectively) are obtained as single crystals. All the compounds crystallize in orthorhombic chiral space group P212121. Compounds 2 and 3 are isostructural, and their structure consists in helicoïdal chains of M(II) centres linked by carboxylate bridges. The magnetic data indicate a rather weak coupling interaction between paramagnetic centres. The Mn(II) compound 1 exhibits antiferromagnetic ordering at TN = 2.64 K. The Co(II) and Ni(II) compounds show ferromagnetic interactions within the chains. For 3, the chains couple antiferromagnetically, which leads to a metamagnetic behaviour with TN = 1.69 K. 相似文献
48.
Kouroush Sadegh Zadeh Howard C Elman Hubert J Montas Adel Shirmohammadi 《Biomedical engineering online》2007,6(1):24
Background
Biological mass transport processes determine the behavior and function of cells, regulate interactions between synthetic agents and recipient targets, and are key elements in the design and use of biosensors. Accurately predicting the outcomes of such processes is crucial to both enhancing our understanding of how these systems function, enabling the design of effective strategies to control their function, and verifying that engineered solutions perform according to plan. 相似文献49.
Mohammed I. Al-Daej Mohamed M. El-Malky Muhammad N. Sattar Adel A. Rezk Muhammad N. Naqqash Jameel M. Al-Khayri 《Phyton》2022,91(9):1905-1922
Rice stem borer (Chilo agamemnon Bles.) is a primary insect pest of rice and is a major limiting factor to rice
production. Breeding for insect-resistant crop varieties has been an economic way of integrated pest management
(IPM) as it offers a viable and ecologically acceptable approach. This study was aimed to evaluate rice genotypes
for their resistance against rice stem borer. Seven parental genotypes with twenty one F1 crosses were evaluated
for genotypic variation in field experiments. Analysis of variance revealed significant differences for the studied
traits in almost all crosses and parents. In addition, the mean squares of parents versus their crosses were signifi-
cant for stem borer resistance and other associated traits. Moreover, both general combining ability (GCA) and
specific combining ability (SCA) variances were highly significant for all characters studied in the F1 generation.
Based on GCA, 4 genotypes (Sakha101, Gz6903-3-4-2-1, Gz9577-4-1-1 and Hassawi) exhibited highly significant
negative values for stem borer resistance (–0.53, –1.06, –0.18 and –0.49, respectively) indicating they are the best
combiners for stem borer resistance. Based on SCA analysis, nine cross combinations showed highly significant
negative effects for stem borer resistance. Similarly, the cross Giza178 Hassawi was the best combination with
significantly highest value for early maturity. In addition, seven crosses showed highly significant negative
SCA for plant height trait. On the other hand, for panicle length, number of primary branches/panicle, panicle
weight and 1000-grain weight, seven, four, eight and six crosses showed highly significant positive SCA, respectively. The result further revealed that the non-additive dominance genetic variance was higher than the additive
variance for all evaluated traits indicating that non-additive genetic variances have a role in their inheritance. The
broad-sense heritability estimates were high for all the studied traits. The stem borer resistance was significantly
correlated with panicle weight and 1000-grain weight, which also showed a highly significant correlation with
grain yield/plant. Thus these traits can be effectively employed in a breeding program to confer resistance against
stem borer infestation in rice. It was further supported by biplot analysis, which clustered these potentially important traits into two quadrants showing their importance in any future breeding program to control stem borer
infestation. This study has contributed valuable information for evaluation of genetic diversity in the local rice
germplasm and its utilization in futuristic rice genetic improvement programs. 相似文献
50.
Alireza Timcheh HaririSeyed Adel Moallem Mahmoud MahmoudiHossein Hosseinzadeh 《Phytomedicine》2011,18(6):499-504
In this study, the effect of crocin and safranal was studied against subacute toxicity of diazinon (DZN) on hematological and genotoxicity indices in rats. The rats were divided into 16 groups consisted of 6 rats in control, diazinon, vitamin E, vitamin E and DZN, crocin (3 doses), crocin (3 doses) and DZN, safranal (3 doses), safranal (3 doses) and DZN groups. Vitamin E (200 IU/kg), safranal at doses 0.025, 0.05 and 0.1 ml/kg and crocin at doses 50, 100 and 200 mg/kg were injected intraperitoneally to rats three times per week alone or with DZN (20 mg/kg/day, orally) for 4 weeks. Hematological parameters were evaluated at the end of 4 weeks. The evaluation of genotoxicity was done using the micronucleus assay. Vitamin E and, at lower doses, safranal (0.025 and 0.05 ml/kg) and crocin (50 mg/kg) restored the reduction of red blood cell, hemoglobin and hematocrit indices induced by DZN. These agents at some doses also prevented the reduction in platelets counts indices in diazinon treated group. A significant increase in reticulocyte was induced by diazinon. Vitamin E, safranal (0.025 or 0.05 ml/kg) and all doses of crocin decreased this effect of diazinon. In all doses vitamin E, crocin and safranal did not inhibit the effect of diazinon on RBC cholinesterase activity. A significant increase in micronucleus indices was seen with diazinon. Vitamin E, safranal and crocin could not prevent this genotoxicity. This study showed that vitamin E, safranal and crocin (without effects on cholinesterase) reduced diazinon hematological toxicity, but they did not prevent the genotoxicity induced by diazinon. 相似文献