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排序方式: 共有190条查询结果,搜索用时 15 毫秒
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Suryapranata H Boland JL Pieper M Legrand VL Bonnier JJ Juliard JM Vrolix MC Seabra-Gomes R Hamburger JN Roguin A Oosterwijk C Van Es GA Beyar R Serruys PW 《International journal of cardiovascular interventions》2000,3(1):21-28
BACKGROUND: Although safety and efficacy of the beStent (Medtronic Inc., Santa Rosa, CA, USA) have been described, the long-term angiographic and clinical outcomes have yet to be investigated. The ROSE (Registry for Optimal beStent Evaluation) trial was designed to assess the procedural safety of single 15 mm beStent implantation, and the six-month angiographic and 12-month clinical outcomes of patients treated with this novel coronary stent. METHODS: Patients with angina and a single de novo lesion in a native coronary artery of >/=2.75 mm diameter were included in this multicenter, prospective, observational trial. Clinical follow-up was obtained at one, six and 12 months. Angiography was performed before and after the stent implantation and at six months. The primary end-point included major adverse cardiac events (death, myocardial infarction and target lesion revascularization), major bleeding complications, and thrombotic occlusions at one-month follow-up. Secondary end-points were major cardiac-event-free survival at six- and 12-month follow-up and angiographic restenosis at six months. A total of 120 patients (80% male, mean age 58.6 +/- 10.6 years) with stable (48%) or unstable (44%) angina pectoris were allocated. The target vessel reference diameter pre-procedure was 2.85 +/- 0.52 mm. RESULTS: Minimal lumen diameter pre/post and at follow-up was 0.97 +/- 0.28 mm, 2.53 +/- 0.40 mm and 1.86 +/- 0.63 mm, respectively. Restenosis rate according to the >50% diameter stenosis criterion at six-month follow-up was 21.5%. At 12 months, the event-free survival rate was 75% (no deaths, two Q-wave and seven non-Q-wave infarctions, five bypass surgery interventions and 16 target lesion revascularizations), whilst 87% of the patients were free of angina pectoris. CONCLUSION: Despite the relatively high percentage of small vessels, the outcome of the ROSE trial is comparable to those observed in previous stent trials, indicating that the coronary beStent is safe and effective as a primary device for the treatment of native coronary artery lesions in patients with (un)stable angina pectoris. 相似文献
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Xianghai Ye Stewart R Brown Kátia Nones Luiz L Coutinho Jack CM Dekkers Susan J Lamont 《遗传、选种与进化》2007,39(1):73-89
Myostatin is a negative regulator of skeletal muscle growth. We evaluated effects of myostatin polymorphisms in three elite commercial broiler chicken lines on mortality, growth, feed conversion efficiency, ultrasound breast depth, breast percentage, eviscerated carcass weight, leg defects, blood oxygen level, and hen antibody titer to infectious bursal disease virus vaccine. Progeny mean data adjusted for fixed and mate effects and DNA from 100 sires per line were used. Single nucleotide polymorphisms (SNPs) of the myostatin gene segregating in these lines were identified by designing specific primers, amplifying individual DNA in each line by polymerase chain reaction, cloning, sequencing and aligning the corresponding products. Individual sires were genotyped for five identified SNPs which contributed to eight haplotypes. Frequencies of SNP alleles and haplotypes differed between lines. Using the allele substitution effect model, the myostatin SNPs were found to have significant (P < 0.031) associations with growth, mortality, blood oxygen and hen antibody titer to infectious bursal disease virus vaccine, although the associations were not often consistent across lines. These results suggest that the myostatin gene has pleiotropic effects on broiler performance. 相似文献
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Eddy J Smid Oylum Erkus Maciej Spus Judith CM Wolkers-Rooijackers Svetlana Alexeeva Michiel Kleerebezem 《Microbial cell factories》2014,13(Z1):S2
This review describes the recent advances made in the studies of the microbial community of complex and undefined cheese starter cultures. We report on work related to the composition of the cultures at the level of genetic lineages, on the presence and activity of bacteriophages and on the population dynamics during cheese making and during starter culture propagation. Furthermore, the link between starter composition and starter functionality will be discussed. Finally, recent advances in predictive metabolic modelling of the multi-strain cultures will be discussed in the context of microbe-microbe interactions. 相似文献
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Ö. Erküner M. Rienstra I. C. Van Gelder U. Schotten H. J. G. M. Crijns J. G. L. M. Luermans 《Netherlands heart journal》2018,26(4):177-181
Cardiovascular implantable electronic devices (CIEDs) can detect atrial arrhythmias, i.?e. atrial high-rate episodes (AHRE). The thrombo-embolic risk in patients showing AHRE appears to be lower than in patients with clinical atrial fibrillation (AF) and it is unclear whether the former will benefit from oral anticoagulants. Based on currently available evidence, it seems reasonable to consider antithrombotic therapy in patients without documented AF showing AHRE >24 hours and a CHA2DS2-VASc score (congestive heart failure, hypertension, age ≥75 years [doubled], diabetes mellitus, prior stroke [doubled], vascular disease, age 65–74 years and female sex) ≥1, awaiting definite answers from ongoing randomised clinical trials. In patients with AHRE <24 hours, current literature does not support starting oral anticoagulation. In these patients, intensifying CIED read-outs can be considered to find progression in AHRE duration sooner, enhancing timely stroke prevention. The notion that AHRE and stroke coincide perseveres but should be abandoned since CIED data show a clear disconnect. 相似文献
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Solid-state NMR analysis of membrane proteins and protein aggregates by proton detected spectroscopy
Donghua H. Zhou Andrew J. Nieuwkoop Deborah A. Berthold Gemma Comellas Lindsay J. Sperling Ming Tang Gautam J. Shah Elliott J. Brea Luisel R. Lemkau Chad M. Rienstra 《Journal of biomolecular NMR》2012,54(3):291-305
Solid-state NMR has emerged as an important tool for structural biology and chemistry, capable of solving atomic-resolution structures for proteins in membrane-bound and aggregated states. Proton detection methods have been recently realized under fast magic-angle spinning conditions, providing large sensitivity enhancements for efficient examination of uniformly labeled proteins. The first and often most challenging step of protein structure determination by NMR is the site-specific resonance assignment. Here we demonstrate resonance assignments based on high-sensitivity proton-detected three-dimensional experiments for samples of different physical states, including a fully-protonated small protein (GB1, 6?kDa), a deuterated microcrystalline protein (DsbA, 21?kDa), a membrane protein (DsbB, 20?kDa) prepared in a lipid environment, and the extended core of a fibrillar protein (??-synuclein, 14?kDa). In our implementation of these experiments, including CONH, CO(CA)NH, CANH, CA(CO)NH, CBCANH, and CBCA(CO)NH, dipolar-based polarization transfer methods have been chosen for optimal efficiency for relatively high protonation levels (full protonation or 100?% amide proton), fast magic-angle spinning conditions (40?kHz) and moderate proton decoupling power levels. Each H?CN pair correlates exclusively to either intra- or inter-residue carbons, but not both, to maximize spectral resolution. Experiment time can be reduced by at least a factor of 10 by using proton detection in comparison to carbon detection. These high-sensitivity experiments are especially important for membrane proteins, which often have rather low expression yield. Proton-detection based experiments are expected to play an important role in accelerating protein structure elucidation by solid-state NMR with the improved sensitivity and resolution. 相似文献
120.
Structured regions of α-synuclein fibrils include the early-onset Parkinson's disease mutation sites
Comellas G Lemkau LR Nieuwkoop AJ Kloepper KD Ladror DT Ebisu R Woods WS Lipton AS George JM Rienstra CM 《Journal of molecular biology》2011,411(4):881-895
α-Synuclein (AS) fibrils are the major component of Lewy bodies, the pathological hallmark of Parkinson's disease (PD). Here, we use results from an extensive investigation employing solid-state NMR to present a detailed structural characterization and conformational dynamics quantification of full-length AS fibrils. Our results show that the core extends with a repeated structural motif. This result disagrees with the previously proposed fold of AS fibrils obtained with limited solid-state NMR data. Additionally, our results demonstrate that the three single point mutations associated with early-onset PD—A30P, E46K and A53T—are located in structured regions. We find that E46K and A53T mutations, located in rigid β-strands of the wild-type fibrils, are associated with major and minor structural perturbations, respectively. 相似文献