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141.
142.
Xiaofeng Chen Debra L. Rateri Deborah A. Howatt Anju Balakrishnan Jessica J. Moorleghen Lisa A. Cassis Alan Daugherty 《PloS one》2016,11(4)
AngII and TGF-β interact in development of thoracic and abdominal aortic diseases, although there are many facets of this interaction that have not been clearly defined. The aim of the present study was to determine the effects of TGF-β neutralization on AngII induced-aortic pathologies. Male C57BL/6J mice were administered with either a rabbit or mouse TGF-β neutralizing antibody and then infused with AngII. The rabbit TGF-β antibody modestly reduced serum TGF-β concentrations, with no significant enhancements to AngII-induced aneurysm or rupture. Administration of this rabbit TGF-β antibody in mice led to high serum titers against rabbit IgG that may have attenuated the neutralization. In contrast, a mouse TGF-β antibody (1D11) significantly increased rupture in both the ascending and suprarenal aortic regions, but only at doses that markedly decreased serum TGF-β concentrations. High doses of 1D11 antibody significantly increased AngII-induced ascending and suprarenal aortic dilatation. To determine whether TGF-β neutralization had effects in mice previously infused with AngII, the 1D11 antibody was injected into mice that had been infused with AngII for 28 days and were observed during continued infusion for a further 28 days. Despite near ablations of serum TGF-β concentrations, the mouse TGF-β antibody had no effect on aortic rupture or dimensions in either ascending or suprarenal region. These data provide further evidence that AngII-induced aortic rupture is enhanced greatly by TGF-β neutralization when initiated before pathogenesis. 相似文献
143.
We suggest a numerical model for nano-modified plasmonic optical structure, which facilitates photons to travel larger distances inside a thin-film silicon wafer, to enhance overall absorption in thin-film silicon solar cell. The absorption and scattering calculation is done using the discrete dipole approximation technique which is valid for both small and large-particle regimes. Relaxed geometrical topologies beyond quasi static approximation were addressed in the present model. The model gives a wide range of flexibility to optimize various parameters accurately. The model establishes that aspect ratio 0.5–0.6 and particle size of 140 nm for ellipsoidal shape are optimized parameters for efficient light trapping in 900–1,100 nm spectral range. 相似文献
144.
A protocol for plant regeneration from mesophyll and callus protoplasts of Robinia pseudoacacia L. was developed. For leaves from in vitro raised shoots, an enzyme combination of 2.0% cellulose and 0.3% macerozyme for
a digestion period of 20 h resulted in the best yield of protoplasts (9.45 × 105 protoplast/g fresh weight). Mesophyll-derived protoplasts started cell wall regeneration within 24 h of being embedded in
Nagata and Takebe (NT) medium supplemented with 5 μM NAA and 1 μM BAP followed by the first cell division on day three of
culture and micro-colony (32 cells) formation within day 7–10 in the same medium. However, using callus as the starting material,
a combination of 2.0% cellulose and 1.0% macerozyme for a digestion period of 24 h gave the highest protoplast yield (3.2 × 105 protoplast/g fresh weight). Cell wall regeneration in callus-derived protoplasts started within 24 h followed by the first
cell division on the day three (96 h) and the appearance of microcolonies of more than 32 cells by the end of first week (144 h)
of culture on solid WPM medium supplemented with 5 μM NAA and 1 μM BAP. Microcalli were visible to the naked eye after 45 days
on solid WPM medium. Proliferation of macro-calli was successfully accomplished on solid Murashige and Skoog (MS) medium with
5 μM NAA and 5 μM BAP. Both mesophyll and callus protoplast-derived calli produced shoots on MS medium with 0.5 μM NAA and
1 μM BAP within 25–30 days and multiplied on MS medium with 1.25 μM BAP. Excised microshoots were dipped in 1–2 ml of 2.0 μM
IBA for 24 h under dark aseptic conditions and transferred to double sterilized sand for rooting. The flasks containing sand
were inoculated with Rhizobium for in vitro nodulation. Forty-five plants transferred to pots in the glasshouse established well. 相似文献
145.
Lipase Pseudomonas cepacia (PS) catalyzed transesterification of ethyl 3-phenylpropanoate with eleven alcohols was investigated in three ionic liquids [ILs], [Bmim]BF4, [Bmim]PF6, and [Bmim]Tf2N, consisting of an identical cation and different anions. The yields were higher in hydrophobic ILs [Bmim]Tf2N (55–96%) and [Bmim]PF6 (22–95%), than in hydrophilic [Bmim]BF4 (0–19%). The incubation of lipase PS in hydrophobic ILs for a period of 20–300 days at room temperature resulted in an increased yield of 62–98% in [Bmim]Tf2N and 45–98% in [Bmim]PF6, respectively. The lipase PS-hydrophobic IL mixture was recycled five times without any decrease in the yield of the products. In another set of experiments, the hydrolytic activity of the enzyme was determined after incubation in each of the three ILs and in hexane for 20 days at room temperature. It was found to be 1.8- and 1.6-fold higher in [Bmim]Tf2N and [Bmim]PF6, respectively, remained unchanged in [Bmim]BF4 and was 1.6 times lower in hexane as compared to the non-incubated enzyme. 相似文献
146.
Anju Puri P. Osman Basha Mankesh Kumar Deepak Rajpurohit Gursharn S. Randhawa Shahryar F. Kianian Anantharama Rishi Harcharan S. Dhaliwal 《Functional & integrative genomics》2010,10(3):359-366
T-DNA insertional mutagenesis is one of the most important approaches for gene discovery and cloning. A fertile polyembryo
mutant generated by T-DNA/Ds insertion in Oryza sativa, cv. Basmati 370 showed twin or triple seedlings at a frequency of 15–20%. T-DNA insertion was confirmed by 950 bp hpt gene amplification in the promoter region of the candidate gene. The annotated protein corresponding to the OsPE candidate gene has been reported as a hypothetical protein in O. sativa. OsPE gene lacked functional homologs in other species. No OsPE paralog was found in rice. No conserved domains were found in the protein coded by OsPE. RT-PCR showed the expression of OsPE gene in Basmati 370 shoots. Full-length OsPE gene was cloned in Basmati 370. The combined use of Southern blot, genome walking, TAIL-PCR, RT-PCR techniques, and bioinformatics
led to the identification of a candidate gene controlling the multiple embryos in rice. There is gain of function, i.e., multiple
embryos in the seeds in the knockout mutant OsPE whereas its wild-type allele strictly controls single embryo per seed. The seeds with multiple embryos are distributed at
random in the rice mutant panicle. The origin of multiple embryos, whether apomictic, zygotic or both is under investigation. 相似文献
147.
Roy AA Nunn C Ming H Zou MX Penninger J Kirshenbaum LA Dixon SJ Chidiac P 《The Journal of biological chemistry》2006,281(43):32684-32693
Regulator of G protein signaling (RGS) proteins limit G protein signals. In this study, we investigated the role of RGS2 in the control of G protein signaling cascades in osteoblasts, the cells responsible for bone formation. Expression of RGS2 was up-regulated in primary cultures of mouse calvarial osteoblasts by parathyroid hormone-related peptide (PTHrP)-(1-34), which stimulates G(s) signaling. RGS2 was also up-regulated by extracellular ATP, which selectively activates G(q), as well as by forskolin and phorbol myristate acetate, which activate targets downstream of G(s) and G(q), respectively. To assess the role of endogenous RGS2, we characterized G(s) and G(q) signaling in osteoblasts derived from wild type and rgs2(-/-) mice. Under control conditions, nucleotide-stimulated calcium release, endothelin-stimulated accumulation of inositol phosphates, and PTHrP-stimulated cAMP accumulation were equivalent in osteoblasts isolated from wild type and rgs2(-/-) mice. Thus, basal levels of endogenous RGS2 do not appear to regulate G(s) or G(q) signaling in osteoblasts. Interestingly, forskolin treatment of wild type but not rgs2(-/-) osteoblasts suppressed both endothelin-stimulated accumulation of inositol phosphates and nucleotide-stimulated calcium release, indicating that up-regulation of RGS2 by G(s) signaling desensitizes G(q) signals. Furthermore, pretreatment with ATP suppressed PTHrP-dependent cAMP accumulation in wild type but not rgs2(-/-) osteoblasts, implying that up-regulation of RGS2 by G(q) signaling desensitizes G(s) signals. Our findings demonstrate that endogenously expressed RGS2 can limit G(s) signaling. Moreover, up-regulation of RGS2 contributes to cross-desensitization of G(s)- and G(q)-coupled signals. 相似文献
148.
Ajay Gaur Kesaraju Shailaja Anju Singh Veluri Arunabala Borusu Satyarebala Lalji Singh 《Conservation Genetics》2006,7(6):1005-1008
The Asiatic lion (Panthera leo persica) is driven to a single habitat in Gir forests in India for its survival. In order to devise adequate conservation and management strategies for this critically endangered species, it is important to characterize its genetic diversity and understand its population structure. Here we report twenty microsatellite loci, in addition to seven reported earlier, from the genome of a pure Asiatic lion. The microsatellite loci described here will provide potentially useful markers for the assessment of genetic variability in the only existing wild population of the Asiatic lions and other big cat species. 相似文献
149.
4-hydroxyisoleucine an unusual amino acid as antidyslipidemic and antihyperglycemic agent 总被引:2,自引:0,他引:2
Narender T Puri A Shweta Khaliq T Saxena R Bhatia G Chandra R 《Bioorganic & medicinal chemistry letters》2006,16(2):293-296
Trigonella foenum-graecum, commonly known as fenugreek, is an annual herbaceous plant. From the seeds of T. foenum-graecum an unusual amino acid, 4-hydroxyisoleucine 5, has been isolated, which significantly decreased the plasma triglyceride levels by 33% (P<0.002), total cholesterol (TC) by 22% (P<0.02), and free fatty acids by 14%, accompanied by an increase in HDL-C/TC ratio by 39% in the dyslipidemic hamster model. 相似文献
150.
Christian D Helfrich Laura J Damschroder Hildi J Hagedorn Ginger S Daggett Anju Sahay Mona Ritchie Teresa Damush Marylou Guihan Philip M Ullrich Cheryl B Stetler 《Implementation science : IS》2010,5(1):1-20