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61.
62.
Astragalus argaeus is critically endangered endemic species growing only on Erciyes Mountain in Kayseri. Inter simple sequence repeat (ISSR) markers were chosen to detect the genetic diversity in four populations of A. argaeus. Ten primers were used to assess the diversity among 96 genotypes collected from the four localities in Erciyes Mountain. A total of 78 bands were scored, of which 44 (55.8%) were polymorphic. The unweighted pair group method arithmetic average (UPGMA) and principle component analysis (PCoA) showed moderate genetic diversity at the species and population level. The percentages of polymorphic bands (PPB) ranged from 53.8 to 61.5 (58.01%?±?3.2) and average gene diversity (h) at the population and species level was estimated to be 0.17 and 0.23, respectively. The Shannon’s information index (SI) ranged from 0.24 to 0.29 at the population level and was 0.35 at the species level. The determined gene flow (Nm) was 1.83. The UPGMA tree indicated that the four populations were not genetically distinct obviously. In analysis of molecular variance (AMOVA), the percentage of the variance was 38.72% among populations and 61.28% within populations. The data which small population size, habitat fragmentation and moderate levels of genetic diversity demonstrate that A. argaeus possess threat of extinction if its narrow habitat is destroyed. 相似文献
63.
A spatial genetics approach to inform vector control of tsetse flies (Glossina fuscipes fuscipes) in Northern Uganda 下载免费PDF全文
Norah Saarman Robert Opiro Chaz Hyseni Richard Echodu Kirstin Dion Elizabeth A. Opiyo Augustine W. Dunn Giuseppe Amatulli Serap Aksoy Adalgisa Caccone 《Ecology and evolution》2018,8(11):5336-5354
Tsetse flies (genus Glossina) are the only vector for the parasitic trypanosomes responsible for sleeping sickness and nagana across sub‐Saharan Africa. In Uganda, the tsetse fly Glossina fuscipes fuscipes is responsible for transmission of the parasite in 90% of sleeping sickness cases, and co‐occurrence of both forms of human‐infective trypanosomes makes vector control a priority. We use population genetic data from 38 samples from northern Uganda in a novel methodological pipeline that integrates genetic data, remotely sensed environmental data, and hundreds of field‐survey observations. This methodological pipeline identifies isolated habitat by first identifying environmental parameters correlated with genetic differentiation, second, predicting spatial connectivity using field‐survey observations and the most predictive environmental parameter(s), and third, overlaying the connectivity surface onto a habitat suitability map. Results from this pipeline indicated that net photosynthesis was the strongest predictor of genetic differentiation in G. f. fuscipes in northern Uganda. The resulting connectivity surface identified a large area of well‐connected habitat in northwestern Uganda, and twenty‐four isolated patches on the northeastern margin of the G. f. fuscipes distribution. We tested this novel methodological pipeline by completing an ad hoc sample and genetic screen of G. f. fuscipes samples from a model‐predicted isolated patch, and evaluated whether the ad hoc sample was in fact as genetically isolated as predicted. Results indicated that genetic isolation of the ad hoc sample was as genetically isolated as predicted, with differentiation well above estimates made in samples from within well‐connected habitat separated by similar geographic distances. This work has important practical implications for the control of tsetse and other disease vectors, because it provides a way to identify isolated populations where it will be safer and easier to implement vector control and that should be prioritized as study sites during the development and improvement of vector control methods. 相似文献
64.
Mine Aksoy M. Serhat Ozaslan 《Journal of enzyme inhibition and medicinal chemistry》2016,31(4):546-550
Glutathione S-transferases (GSTs) are an important enzyme family which play a critical role in detoxification system. In our study, GST was purified from muscle tissue of Chalcalburnus tarichii Pallas with 301.5-fold purification and 19.07% recovery by glutathione agarose affinity chromatography. The purity of enzyme was checked by sodium dodecyl sulfate–polyacrylamide gel electrophoresis, showing a two band, because of having heterodimer structure. KM values were 1.59 and 0.53?mM for 1-chloro-2,4-dinitrobenzene (CDNB) and glutathione (GSH), respectively. Vmax values for CDNB and GSH were also determined as 5.58 and 1.88?EU/mL, respectively. In addition, inhibition effects of Ag+, Cu2+, Cd2+, Fe3+, Pb2+, Cr2+, Co2+ and Zn2+ metal ions were investigated on the enzyme activity and IC50, Ki values were calculated for these metal ions. 相似文献
65.
66.
Mehmet Aksoy Ali Ahiskalioglu Ilker Ince Mine Celik Aysenur Dostbil Ufuk Kuyrukluyildiz Durdu Altuner Nezahat Kurt Halis Suleyman 《Experimental Animals》2015,64(4):391-396
Thiopental sodium (TPS) needs to be applied together with adrenalin in order to establish
its analgesic effect in general anesthesia. We aimed to investigate the effect of TPS on
the claw pain threshold in rats and evaluated its relationship with endogenous adrenalin
(ADR), noradrenalin (NDR), and dopamine (DOP) levels. Intact and adrenalectomized rats
were used in the experiment. Intact animals were divided into the following groups: 15
mg/kg TPS (TS), 0.3 mg/kg ADR+15 mg/kg TPS (ATS) and 0.3 mg/kg ADR alone (ADR).
Adrenalectomized animals were divided into the following groups: 15 mg/kg TPS (A-TS), 0.3
mg/kg ADR+15 mg/kg TPS (A-ATS) and 0.3 mg/kg ADR alone (A-ADR). Claw pain threshold and
blood ADR, NDR, and DOP levels were measured. The TS group’s claw pain threshold was found
low. However, the claw pain thresholds of the ATS and ADR groups increased significantly.
In the A-TS group, the pain threshold decreased compared with normal, and in the A-ATS and
A-ADR groups, the pain threshold increased. TPS reduced the blood ADR levels in intact
rats; however, no significant changes were observed in the NDR and DOP levels. #TPS
provides hyperalgesia by reducing the production of ADR in rats. The present study shows
that to achieve analgesic activity, TPS needs to be applied together with ADR. 相似文献
67.
Interspecific Transfer of Bacterial Endosymbionts between Tsetse Fly Species: Infection Establishment and Effect on Host Fitness 总被引:2,自引:1,他引:1 下载免费PDF全文
BrianL. Weiss Rosa Mouchotte Rita V. M. Rio Yi-neng Wu Zheyang Wu Abdelaziz Heddi Serap Aksoy 《Applied microbiology》2006,72(11):7013-7021
Tsetse flies (Glossina spp.) can harbor up to three distinct species of endosymbiotic bacteria that exhibit unique modes of transmission and evolutionary histories with their host. Two mutualist enterics, Wigglesworthia and Sodalis, are transmitted maternally to tsetse flies' intrauterine larvae. The third symbiont, from the genus Wolbachia, parasitizes developing oocytes. In this study, we determined that Sodalis isolates from several tsetse fly species are virtually identical based on a phylogenetic analysis of their ftsZ gene sequences. Furthermore, restriction fragment-length polymorphism analysis revealed little variation in the genomes of Sodalis isolates from tsetse fly species within different subgenera (Glossina fuscipes fuscipes and Glossina morsitans morsitans). We also examined the impact on host fitness of transinfecting G. fuscipes fuscipes and G. morsitans morsitans flies with reciprocal Sodalis strains. Tsetse flies cleared of their native Sodalis symbionts were successfully repopulated with the Sodalis species isolated from a different tsetse fly species. These transinfected flies effectively transmitted the novel symbionts to their offspring and experienced no detrimental fitness effects compared to their wild-type counterparts, as measured by longevity and fecundity. Quantitative PCR analysis revealed that transinfected flies maintained their Sodalis populations at densities comparable to those in flies harboring native symbionts. Our ability to transinfect tsetse flies is indicative of Sodalis ' recent evolutionary history with its tsetse fly host and demonstrates that this procedure may be used as a means of streamlining future paratransgenesis experiments. 相似文献
68.
Aksoy P Escande C White TA Thompson M Soares S Benech JC Chini EN 《Biochemical and biophysical research communications》2006,349(1):353-359
The SIRT 1 enzyme is a NAD dependent deacetylase implicated in ageing, cell protection, and energy metabolism in mammalian cells. How the endogenous activity of SIRT 1 is modulated is not known. The enzyme CD38 is a multifunctional enzyme capable of synthesis of the second messenger, cADPR, NAADP, and ADPR. However, the major enzymatic activity of CD38 is the hydrolysis of NAD. Of particular interest is the fact that CD38 is present on the inner nuclear membrane. Here, we investigate the modulation of the SIRT 1 activity by CD38. We propose that by modulating availability of NAD to the SIRT1 enzyme, CD38 may regulate SIRT1 enzymatic activity. We observed that in CD38 knockout mice, tissue levels of NAD are significantly increased. We also observed that incubation of purified recombinant SIRT1 enzyme with CD38 or nuclear extracts of wild-type mice led to a significant inhibition of its activity. In contrast, incubation of SIRT1 with cellular extract from CD38 knockout mice was without effect. Furthermore, the endogenous activity of SIRT1 was several time higher in nuclear extracts from CD38 knockout mice when compared to wild-type nuclear extracts. Finally, the in vivo deacetylation of the SIRT1 substrate P53 is increased in CD38 knockout mice tissue. Our data support the novel concept that nuclear CD38 is a major regulator of cellular/nuclear NAD level, and SIRT1 activity. These findings have strong implications for understanding the basic mechanisms that modulate intracellular NAD levels, energy homeostasis, as well as ageing and cellular protection modulated by the SIRT enzymes. 相似文献
69.
Brassinolide (BR), which is the most biologically active brassinosteroid, was used to examine the potential effect of hormone
on cotton somatic embryogenesis. Ten-day-old cotton (Gossypium hirsutum L., cv. Cooker) seedlings were used for explant source and hypocotyls were removed and cultured on MS basal medium with B5 vitamins supplemented with 1 mg/L 6-benzylaminopurine + 0.5 mg/L kinetin for callus induction. After one month proliferating
calli pieces were collected and cultured on MS basal medium containing various concentrations of BR (0.1, 0.5, 1.0 μM) with
their controls. BR treatments were negatively effective on the fresh weight of calli when compared to control. Differential
somatic embryogenesis maturation rates due to BR treatment were observed. Somatic embryogenesis was stimulated especially
for transition to cotyledonary phase at 0.5 mg/L BR. Histological preparations from embryogenic calli and somatic embryos
at different stages of development revealed the spontaneous polyploidisation during early somatic embryogenesis on BR-treated
calli. Present results suggest that BR negatively effected calli growth, however, had a stimulating role in maturation of
somatic embryos. 相似文献
70.
Ozgur Yamak N. Ayca Kalkan Serpil Aksoy Haydar Altinok Nesrin Hasirci 《Process Biochemistry》2009,44(4):440-445
Laccase enzyme (L) from Trametes versicolor was entrapped in three hydrogel structures namely poly(acrylamide-N-isopropylacrylamide), P(AAm-NIPA), and semi-interpenetrating networks of poly(acrylamide)/alginate, P(AAm)/Alg, and poly(acrylamide-N-isopropylacrylamide)/alginate, P(AAm-NIPA)/Alg. The optimum temperatures for free and all immobilized systems were found to be 40 °C. For free and immobilized laccase systems of P(AAm-NIPA)-L, P(AAm)/Alg-L and P(AAm-NIPA)/Alg-L, Km values were found to be 6.7 × 10?3, 8.8 × 10?2, 5.5 × 10?2 and 1.8 × 10?2 mM; Vmax values were calculated as 1.8 × 10?3, 2.5 × 10?2, 1.5 × 10?2 and 6.1 × 10?3 mM min?1, respectively. For free and the same immobilized systems, the enzymes retained 42%, 91%, 79% and 86% of their initial activities at the end of 56 days of storage. After using the mentioned immobilized systems repeatedly 10 times, they retained 77%, 71% and 84% of their original activities, respectively. For free and the same immobilized systems, decolorization of Acid Orange 52 (AO52) in 6 h were found to be 63%, 50%, 48% and 66%, respectively. Addition of 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid), ABTS, into the assay medium increased these values up to 73%, 73%, 74% and 75%, respectively. 相似文献