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101.
Ke T Jeong EK Wang X Feng Y Parker DL Lu ZR 《International journal of nanomedicine》2007,2(2):191-199
Cyclic Arg-Gly-Asp-D-Phe-Lys [c(RGDfK)] targeted poly(L-glutamic acid) (PGA)-(Gd-DO3A) conjugate with a biodegradable cystamine spacer was prepared and evaluated for in vivo detection of an angiogenesis biomarker, alpha(v)beta3 integrin, in neoplastic tissues with T1 mapping, a quantitative magnetic resonance imaging (MRI) technique. The binding activity of the c(RGDfK) containing conjugate was investigated using in vitro vitronectin assay with human prostate carcinoma DU145 cell line and Kaposi's sarcoma SLK cell line. The peptide c(RGDfK) and PGA-cystamine-(Gd-DO3A) conjugate were used as controls. The binding affinity of polymer bound c(RGDfK) was slightly lower than free c(RGDfK) peptide. The RGD targeted conjugate had higher binding affinity to the DU145 cells than the SLK cells, which was consistent to free c(RGDfK). The imaging of alpha(v)beta3 integrin with targeted PGA-cystamine-(Gd-DO3A) was evaluated in nude mice bearing DU145 and SLK xenografts at a dose of 5 micromol-Gd/kg. The targeted conjugate demonstrated higher in vivo binding affinity to the DU145 xenografts than the SLK xenografts, resulting in a significant decrease of T1 values of water protons in the periphery of the DU145 tumors as shown in the MR T1 maps. No significant decrease of T1 values was observed in the SLK tumor with the targeted conjugate and in both tumors with the non-targeted conjugate. The targeted polymeric Gd(III) chelate conjugate with a degradable spacer has the potential to be a new paradigm for safe and effective probes in molecular imaging with quantitative MR T1 mapping. 相似文献
102.
Lai F Sinico C De Logu A Zaru M Müller RH Fadda AM 《International journal of nanomedicine》2007,2(3):419-425
The effect of SLN incorporation on transdermal delivery and in vitro antiherpetic activity of Artemisia arborescens essential oil was investigated. Two different SLN formulations were prepared using the hot-pressure homogenization technique, Compritol 888 ATO as lipid, and Poloxamer 188 and Miranol Ultra C32 as surfactants. Formulations were examined for their stability for two years by monitoring average size distribution and zeta potential values. The antiviral activity of free and SLN incorporated essential oil was tested in vitro against Herpes Simplex Virus-1 (HSV-1) by a quantitative tetrazolium-based colorimetric method (MTT), while the effects of essential oil incorporation into SLN on both the permeation through and the accumulation into the skin strata was investigated by using in vitro diffusion experiments through newborn pig skin and an almond oil Artemisia essential oil solution as a control. Results showed that both SLN formulations were able to entrap the essential oil in high yields and that the mean particle size increased only slightly after two years of storage, indicating a high physical stability. In vitro antiviral assays showed that SLN incorporation did not affect the essential oil antiherpetic activity. The in vitro skin permeation experiments demonstrated the capability of SLN of greatly improving the oil accumulation into the skin, while oil permeation occurred only when the oil was delivered from the control solution. 相似文献
103.
Kim D Lee JS Park YK Kim JF Jeong H Oh TK Kim BS Lee CH 《Journal of applied microbiology》2007,102(4):937-944
AIMS: Hahella chejuensis KCTC 2396 produces red pigments, showing antibacterial and algicidal activities. The main red-coloured metabolite of the pigments was identified as antibiotic prodigiosin. With the expectation that the red pigments are a mixture of a series of close relatives, the aim of the present study is to detect new antibiotic prodigiosin analogues and to analyse the biosynthetic pattern for prodiginines in KCTC 2396. METHODS AND RESULTS: Except prodigiosin, the other constituents in the red pigments were confirmed as well-known dipyrrolyldipyrromethene prodigiosin, norprodigiosin, and undecylprodiginine. Additionally, four new prodigiosin analogues, each of which was distinguished from prodigiosin (C(5)), according to differences in alkyl chain length (C(3)-C(7)), were detected in small quantities by liquid chromatography mass spectrometry/mass spectrometry spectroscopy. Owing to the presence of a cytotoxic methoxy group, it is expected that all the new prodigiosin analogues are bioactive. CONCLUSIONS: Four characterized prodiginines, including prodigiosin and four new prodigiosin analogues are produced in different ratio in KCTC 2396. All of the prodiginines possess a common linear tripyrrolyl structure and a cytotoxic methoxy group. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows for the first time that KCTC 2396 is able to produce antibiotic prodigiosin, undecylprodiginine and new prodigiosin analogues in a mixture of pigments. It is also shown that KCTC 2396 possesses a novel system for the simultaneous production of multiple prodiginines in a single micro-organism. 相似文献
104.
105.
Hélène Bertrand Sophie Bombard David Monchaud Marie-Paule Teulade-Fichou 《Journal of biological inorganic chemistry》2007,12(7):1003-1014
A novel platinum–quinacridine hybrid, comprising a monofunctional Pt moiety and a G-quadruplex ligand (mono-para-quinacridine or MPQ), has been synthesized and shown to interact with quadruplex DNA via a dual noncovalent/covalent binding
mode. Denaturing gel electrophoresis was used to separate the various platination products of 22AG (an oligonucleotide that
mimics the human telomeric repeat) by Pt-MPQ, and it was shown that two platinated adducts are highly stable quadruplex structures.
Dimethylsulfate/piperidine treatment and 3′-exonuclease digestion of the isolated adducts allowed us to precisely determine
the platination pattern of 22AG by Pt-MPQ, which displays three main sites G2, G10 and G22. Data presented herein support
the hypothesis that Pt-MPQ traps preferentially the antiparallel structure of the 22AG quadruplex. Finally, the kinetics of
Pt-MPQ platination using a construct containing both quadruplex DNA and a duplex DNA parts provide the first insights into
the Pt-MPQ preference for quadruplex DNA over duplex DNA. 相似文献
106.
Youhei Tanaka Naohiro Hayashibara Tomoya Enokido Makoto Takizawa 《Cluster computing》2007,10(1):81-93
In this paper, we discuss how to realize fault-tolerant applications on distributed objects. Servers supporting objects can
be fault-tolerant by taking advantage of replication and checkpointing technologies. However, there is no discussion on how
application programs being performed on clients are tolerant of clients faults. For example, servers might block in the two-phase
commitment protocol due to the client fault. We newly discuss how to make application programs fault-tolerant by taking advantage
of mobile agent technologies where a program can move from a computer to another computer in networks. An application program
to be performed on a faulty computer can be performed on another operational computer by moving the program in the mobile
agent model. In this paper, we discuss a transactional agent model where a reliable and efficient application for manipulating objects in multiple computers is realized in the mobile agent
model. In the transactional agent model, only a small part of the application program named routing subagent moves around computers. A routing subagent autonomously finds a computer which to visit next. We discuss a hierarchical navigation
map which computer should be visited price to another computer in a transactional agent. A routing subagent makes a decision
on which computer visit for the hierarchical navigation map. Programs manipulating objects in a computer are loaded to the
computer on arrival of the routing subagent in order to reduce the communication overhead. This part of the transactional
agent is a manipulating subagent. The manipulation subagent still exists on the computer even after the routing subagent leaves the computer in order to hold
objects until the commitment. We assume every computer may stop by fault while networks are reliable. There are kinds of faulty
computers for a transactional agent; current, destination, and sibling computers where a transactional agent now exists, will move, and has visited, respectively. The types of faults are detected
by neighbouring manipulation subagents by communicating with each other. If some of the manipulation subagents are faulty,
the routing subagent has to be aborted. However, the routing subagent is still moving. We discuss how to efficiently deliver
the abort message to the moving routing subagent. We evaluate the transactional agent model in terms of how long it takes
to abort the routing subagent if some computer is faulty.
相似文献
Makoto TakizawaEmail: |
107.
108.
Won Gi Yoo Sanghyun Lee Myoung-Ro Lee Mi-Ran Yun Taesoo Kwon Dae-Won Kim 《Bioinformation》2015,11(1):17-20
The increase in prevalence of antimicrobial resistance makes the search for new antibiotic agents imperative. Antimicrobial
peptides (AMPs) from natural resources have been recognized as suitable tools to combat antibiotic-resistant bacteria. The liver
fluke Clonorchis sinensis living in germ-filled environments could be a good source of antimicrobials. Here, we report the use of a
rational protocol that combines AMP predictions based on their physicochemical properties and their in vivo stability to discover
AMP candidates from the entire genome of C. sinensis. To screen AMP candidates, in silico analyses based on the physicochemical
properties of known AMPs, such as length, charge, isoelectric point, and in vitro and in vivo aggregation values were performed. To
enhance their in vivo stability, proteins having proteolytic cleavage sites were excluded. As a consequence, four high-activity, highstability
peptides were identified. These peptides could be potential starting materials for the development of new AMPs via
structural modification and optimization. Thus, this study proposes a refined computational method to develop new AMPs and
identifies four AMP candidates, which could serve as templates for further development of peptide antibiotics. 相似文献
109.
Contamination of plants and seeds with microorganisms is one of the main problems in the production and distribution of various agricultural products, as well as raw herbal material for the preparation of herbal remedies. In targeting microbial contamination, among other bacteria, Bacillus species showed a significant capacity for biocontrol. The antifungal activity of 14 isolates of Bacillus spp. against 15 fungal isolates from medicinal plants was examined utilizing a dual plate assay. The strongest and broadest antagonistic activity against all fungi tested was exhibited by isolates SS-12.6 and SS-13.1 (from a 43% to 74% reduction in fungal growth), while isolates SS-39.1 and SS-39.3 were effective against the fewest fungus species and also had the weakest antifungal activity. The effect of a crude lipopeptide extract (CLE) of Bacillus sp. SS-12.6 was similar to that achieved by a dual culture with isolate SS-12.6, confirming that the antagonism was the result of the antifungal activities of lipopeptides. In addition, essential oils of thyme (0.55 mg/mL) and savory (0.32 mg/mL) in various combinations with the CLE of SS-12.6 were tested for antifungal activity, and additive and synergistic effects for some of the fungi were obtained. When testing the effect of CLE, oils (0.40 mg/mL for thyme oil and 0.21 mg/mL for savory oil) and combinations in situ on marigold seeds, a reduction of total fungal infection without an adverse effect on germination was accomplished by 6-h treatments with CLE of SS-12.6 (85% reduction of fungal infection and 63% germination), supernatant from liquid culture of SS-12.6 (more than 90% reduction of fungal infection with 69% seed germination) and combinations of CLE and savory oil (77% reduction of fungal infection and 62% seed germination) and CLE with thyme and savory oils (about 75% reduction of fungal infection with 69% seed germination). 相似文献
110.
Nacéra Tigrine‐Kordjani Brahim Youcef Meklati Farid Chemat 《Phytochemical analysis : PCA》2011,22(1):1-9
Introduction – The aerial parts of Zygophyllum album L. are used in folk medicine as an antidiabetic agent and as a drug active against several pathologies. In this work we present the chemical composition of Algerian essential oils obtained by microwave accelerated distillation (MAD) extraction, a solventless method assisted by microwave. Objective – Under the same analytical conditions and using GC‐FID and GC‐MS, the chemical composition of the essential oil of Zygophyllum album L. extracted by MAD was compared with that achieved using hydrodistillation (HD). Methodology – The extracted compounds were hydrosoluble, and they were removed from the aqueous solution by a liquid extraction with an organic solvent. Results – Employing MAD (100°C, 30 min), the essential oil contained mainly oxygenated monoterpenes with major constituents: carvone and α‐terpineol. However, most of the compounds present in the hydrodistilled volatile fraction were not terpene species, with β‐damascenone as a major constituent. Conclusion – The MAD method appears to be more efficient than HD: after 30 min extraction time, the obtained yields (i.e. 0.002%) were comparable to those provided by HD after 3 h extraction. MAD seems to be more convenient since the volatile fraction is richer in oxygenated monoterpenes, species that are recognised for their olfactory value and their contribution to the fragrance of the essential oil. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献