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1.
The National Institute of General Medical Sciences (NIGMS) at the U.S. National Institutes of Health (NIH) is committed to supporting the safety of the nation’s biomedical research and training environments. Institutional training grants affect many trainees and can have a broad influence across their parent institutions, making them good starting points for our initial efforts to promote the development and maintenance of robust cultures of safety at U.S. academic institutions. In this Perspective, we focus on laboratory safety, although many of the strategies we describe for improving laboratory safety are also applicable to other forms of safety including the prevention of harassment, intimidation, and discrimination. We frame the problem of laboratory safety using a number of recent examples of tragic accidents, highlight some of the lessons that have been learned from these and other events, discuss what NIGMS is doing to address problems related to laboratory safety, and outline steps that institutions can take to improve their safety cultures.All new funding opportunity announcements (FOAs) for training programs supported by the National Institute of General Medical Sciences (NIGMS) contain the expectation that the programs will promote “inclusive, safe and supportive scientific and training environments.” In this context, the word “safe” refers to several aspects of safety. First, we mean an environment free from harassment and intimidation, in which everyone participating is treated in a respectful and supportive manner, optimized for productive learning and research. We also mean that institutions should ensure that their campuses are as safe as possible so that individuals can focus on their studies and research. Finally, we mean safety in the laboratory and clinical spaces. In this Perspective, we focus on this last issue and describe some of the approaches NIGMS is taking to help the biomedical research community move toward an enhanced culture of safety in which core values and the behaviors of leadership, principal investigators (PIs), research staff, and trainees emphasize safety over competing goals. 相似文献
2.
Synthesis, conformational studies and biological activity of N(alpha)-mono-biotinylated rat relaxin.
M N Mathieu J D Wade B Catimel C P Bond E C Nice R J Summers L Otvos G W Tregear 《The journal of peptide research》2001,57(5):374-382
Biotin-avidin immobilization can be a useful tool in structure-function studies of hormone receptors. A crucial step is the preparation of a specifically biotinylated hormone that is able to bind to its receptor while leaving the biotin group free for interaction with avidin. The receptor for relaxin, an ovarian peptidic hormone produced during pregnancy, has not yet been isolated. We therefore undertook to prepare a specifically monobiotinylated rat relaxin for use in ligand-searching strategies. Rat relaxin is a convenient analogue because reliable bioassays exist, thus allowing assessment of the effect of N-biotinylation on bioactivity. To help improve the yield of the two-chain, three-disulfide bond rat relaxin, 2-hydroxy-4-methoxybenzyl (Hmb) backbone protection was used during the solid-phase assembly of the B-chain to help prevent any possible chain aggregation. As a final step, while the protected peptide was still on the resin, the biotin label was introduced at the N-terminus of the B-chain using standard coupling protocols. The chain combination with the A-chain was accomplished in reasonable yield. Secondary structural measurements demonstrated that the biotin caused the starting B-chain to adopt a more ordered conformation. The labelled synthetic relaxin exhibited similar circular dichroism spectra to native and synthetic single B-chain peptides. In addition, the biotinylated relaxin showed no significant difference in its chronotropic activity in the rat isolated heart assay compared with the native peptide. Biosensor studies showed that antibody recognition was retained upon attachment of the synthetic relaxin to the streptavidin-derivatized surface. 相似文献
3.
4.
The colonization of solid PVC surfaces and the acquisition of resistance to germicides by water micro-organisms 总被引:4,自引:1,他引:3
R.W. Vess R.L. Anderson J.H. Carr W.W. Bond M.S. Favero 《Journal of applied microbiology》1993,74(2):215-221
Six common water bacteria were examined for their ability to colonize polyvinyl chloride (PVC) surfaces, survive various germicidal treatment, and re-establish themselves in sterile distilled water (SDW). For each test, two 30·4 cm PVC pipes attached to a 90° PVC elbow were filled with 600 ml of distilled water inoculated with either Pseudomonas aeruginosa, Ps. cepacia, Ps. mesophilica, Acinetobacter anitratus, Mycobacterium chelonae or M. chelonae var. abscessus. After 8 weeks contaminated water was removed and the pipes were exposed to 600 ml of 1 : 213 iodophor disinfectant (ID), 1 : 128 phenolic detergent (P), 1 : 256 quaternary ammonium compound (QA), stock iodophor antiseptic (IA), 2% formaldehyde (F), 10–15 ppm free chlorine (C), 2% glutaraldehyde (G) and 70% ethanol (E). These germicides were periodically sampled, neutralized and examined for surviving organisms. After exposure for 7 d the germicides were removed and each pipe was refilled with SDW. This was assayed at 7 d intervals to determine microbial re-establishment. Samples were removed during microbial conditioning and examined by scanning electron microscopy (SEM). Pseudomonads were isolated directly from ID, QA, C, P and F, and mycobacteria from QA, IA, ID, P, G, C and F. Pseudomonas aeruginosa and Ps. cepacia survived in PVC pipes after 7 d of exposure to P, ID and C; Ps. mesophilica, after C and ID; and both mycobacteria, after C. SEM examination of PVC remnants revealed bacterial attachment and formation of extracellular material with embedded cells. These studies show that common water bacteria can attach and colonize the interior surface of PVC pipes and develop significant resistance to the action of certain germicides. Specific disinfection strategies are needed to control microbial populations that form in water distribution systems. 相似文献
5.
R. W. Chambers J. A. Rose A. S. Rabson H. E. Bond W. T. Hall 《Applied microbiology》1971,22(5):914-918
High-titered yields of human cytomegalovirus (CMV), strain AD 169, were produced in WI-38 cells in large roller bottles. Maximum plaque titers were observed by the 4th day after infection at which time infectivity in the medium was 200 times greater than that associated with the cells. Virus released into the medium was recovered by sedimentation in a sucrose gradient in a continuous-flow centrifuge rotor. Maximal viral infectivity was found at a sucrose concentration of 42%, equivalent to a density of 1.18 g/cm(3). Deoxyribonucleic acid extracted from these preparations was about 80% viral and 20% cellular as judged by equilibrium centrifugation in cesium chloride density gradients. 相似文献
6.
Victor Neira Peter Rabinowitz Aaron Rendahl Blanca Paccha Shawn G. Gibbs Montserrat Torremorell 《PloS one》2016,11(1)
Indirect transmission of influenza A virus (IAV) in swine is poorly understood and information is lacking on levels of environmental exposure encountered by swine and people during outbreaks of IAV in swine barns. We characterized viral load, viability and persistence of IAV in air and on surfaces during outbreaks in swine barns. IAV was detected in pigs, air and surfaces from five confirmed outbreaks with 48% (47/98) of oral fluid, 38% (32/84) of pen railing and 43% (35/82) of indoor air samples testing positive by IAV RT-PCR. IAV was isolated from air and oral fluids yielding a mixture of subtypes (H1N1, H1N2 and H3N2). Detection of IAV RNA from air was sustained during the outbreaks with maximum levels estimated between 7 and 11 days from reported onset. Our results indicate that during outbreaks of IAV in swine, aerosols and surfaces in barns contain significant levels of IAV potentially representing an exposure hazard to both swine and people. 相似文献
7.
Mousumi Bose Sriram Machineni Blanca Oliván Julio Teixeira James J. McGinty Baani Bawa Ninan Koshy Antonia Colarusso Blandine Laferrère 《Obesity (Silver Spring, Md.)》2010,18(6):1085-1091
The goal of this study was to understand the mechanisms of greater weight loss by gastric bypass (GBP) compared to gastric banding (GB) surgery. Obese weight‐ and age‐matched subjects were studied before (T0), after a 12 kg weight loss (T1) by GBP (n = 11) or GB (n = 9), and at 1 year after surgery (T2). peptide YY3–36 (PYY3–36), ghrelin, glucagon‐like peptide‐1 (GLP‐1), leptin, and amylin were measured after an oral glucose challenge. At T1, glucose‐stimulated GLP‐1 and PYY levels increased significantly after GBP but not GB. Ghrelin levels did not change significantly after either surgery. In spite of equivalent weight loss, leptin and amylin decreased after GBP, but not after GB. At T2, weight loss was greater after GBP than GB (P = 0.003). GLP‐1, PYY, and amylin levels did not significantly change from T1 to T2; leptin levels continued to decrease after GBP, but not after GB at T2. Surprisingly, ghrelin area under the curve (AUC) increased 1 year after GBP (P = 0.03). These data show that, at equivalent weight loss, favorable GLP‐1 and PYY changes occur after GBP, but not GB, and could explain the difference in weight loss at 1 year. Mechanisms other than weight loss may explain changes of leptin and amylin after GBP. 相似文献
8.
Evidence for Involvement of an Electron Shuttle in Electricity Generation by Geothrix fermentans 总被引:2,自引:0,他引:2 下载免费PDF全文
In experiments performed using graphite electrodes poised by a potentiostat (+200 mV versus Ag/AgCl) or in a microbial fuel cell (with oxygen as the electron acceptor), the Fe(III)-reducing organism Geothrix fermentans conserved energy to support growth by coupling the complete oxidation of acetate to reduction of a graphite electrode. Other organic compounds, such as lactate, malate, propionate, and succinate as well as components of peptone and yeast extract, were utilized for electricity production. However, electrical characteristics and the results of shuttling assays indicated that unlike previously described electrode-reducing microorganisms, G. fermentans produced a compound that promoted electrode reduction. This is the first report of complete oxidation of organic compounds linked to electrode reduction by an isolate outside of the Proteobacteria. 相似文献
9.
The lower levels of the Lipeón Formation, in the Eastern Cordillera, north-west Argentina, yield a marine-dominated palynomorph assemblage, together with graptolites of mid to late mid Llandovery age (Demirastrites convolutus and probably Stimulograptus sedgwickii zones). The palynomorph assemblage is dominated by acritarchs, but also contains algae and terrestrial cryptospores. Crassiangulina variacornuta, considered a potentially good global biostratigraphical marker for the Upper Llandovery is recovered for the first time from the Silurian of Argentina. The occurrence of this species in strata not younger than late Aeronian, and independently dated by graptolites, indicates an early first appearance for Crassiangulina variacornuta, in the Lipeón Formation, below the Aeronian/Telychian boundary. The lower part of the unit corresponds to a quiet marine environment; thus supporting that Crassiangulina variacornuta is a facies-sensitive acritarch. 相似文献
10.
M Parry-Billings B Leighton G D Dimitriadis R Curi J Bond S Bevan A Colquhoun E A Newsholme 《The International journal of biochemistry》1991,23(9):933-937
1. The effects of tumour bearing on glutamine metabolism in rat skeletal muscle were examined using the Walker 256 carcinosarcoma. 2. There was a rapid and marked decrease in skeletal muscle glutamine content, which was correlated with the size of the tumour, and a decrease in plasma glutamine concentration. 3. The rate of release of glutamine from EDL muscle in vitro was increased in cachectic, tumour bearing animals, but was unaffected from the soleus muscle of the same animals. 4. It is hypothesized that the increase in the rate of muscle glutamine release during cachexia represents a response of this tissue in order to satisfy the demand for glutamine by the tumour or by cells of the immune system. 相似文献