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61.
By comparing versions of mental illness narratives – told by Haredi (Utraorthodox Jews) male patients of a mental health clinic in Israel and by their rabbis – this paper relates to two distinct, yet interrelated, theoretical questions: the place and agency of narrators, and the tension between experience and representation. A pair of narratives exemplifies a pattern in which the patients (Talmudic students) tell a narrative of a sudden breakdown related to a dramatic meeting with a non-human figure (often, a woman) or force. Their rabbis, by contrast, tell a narrative that emphasizes their students' mundane symptoms, ``abnormal' and ``immoral' behavior, and use a local adaptation of a Western psychological explanatory model. A dynamic of inclusion and exclusion emerges as students are seeking legitimization and avoidance of stigma, while their rabbis are silencing themes that challenge social and cultural orders. The different narratives are further interpreted in the context of the micropolitics of the interviews and of identity politics between the Haredim and secular Israelis. This social dynamics shows how differently placed social actors-narrators-interpreters construct differently contested and diverse cultural narratives of a seemingly shared reality. 相似文献
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63.
Daniel Krekeler Pavel Sigalevich A. Teske H. Cypionka Yehuda Cohen 《Archives of microbiology》1997,167(6):369-375
In an investigation on the oxygen tolerance of sulfate-reducing bacteria, a strain was isolated from a 107-fold dilution of the upper 3-mm layer of a hypersaline cyanobacterial mat (transferred from Solar Lake, Sinai). The isolate,
designated P1B, appeared to be well-adapted to the varying concentrations of oxygen and sulfide that occur in this environment.
In the presence of oxygen strain P1B respired aerobically with the highest rates [260 nmol O2 min–1 (mg protein)–1] found so far among marine sulfate-reducing bacteria. Besides H2 and lactate, even sulfide or sulfite could be oxidized with oxygen. The sulfur compounds were completely oxidized to sulfate.
Under anoxic conditions, it grew with sulfate, sulfite, or thiosulfate as the electron acceptor using H2, lactate, pyruvate, ethanol, propanol, or butanol as the electron donor. Furthermore, in the absence of electron donors the
isolate grew by disproportionation of sulfite or thiosulfate to sulfate and sulfide. The highest respiration rates with oxygen
were obtained with H2 at low oxygen concentrations. Aerobic growth of homogeneous suspensions was not obtained. Additions of 1% oxygen to the gas
phase of a continuous culture resulted in the formation of cell clumps wherein the cells remained viable for at least 200
h. It is concluded that strain P1B is oxygen-tolerant but does not carry out sulfate reduction in the presence of oxygen under
the conditions tested. Analysis of the 16S rDNA sequence indicated that strain P1B belongs to the genus Desulfovibrio, with Desulfovibrio halophilus as its closest relative. Based on physiological properties strain P1B could not be assigned to this species. Therefore, a
new species, Desulfovibrio oxyclinae, is proposed.
Received: 7 August 1996 / Accepted: 29 January 1997 相似文献
64.
Summary In liposomes of dimyristoyl lecithin at 40°C, a quantity of water equal to about 11.5 moles water per mole lecithin, or about one-third of the enclosed liposome water or one-fifth of the total pellet water, behaves as if it is unavailable for dissolving sucrose. This phenomenon represents permanent exclusion of sucrose, not simply a space that equilibrates slowly due to the low permeability of sucrose. The amount of nonsolvent water increases with temperature, and is similar to the amount of water bound to the phosphorylcholine groups as estimated by other methods. Nonsolvent water arises from a combination of the forces responsible for salting-out of nonelectrolytes from aqueous solutions by ions, and of steric effects adjacent to a surface. Measured liposome: water partition coeffecients must be corrected for the effect of nonsolvent water. 相似文献
65.
We report that caffeine, in millimolar concentrations, interacts strongly with four common calcium indicator dyes: mag-fura-2, magnesium green, fura-2, and fluo-3. Fluorescence intensities are either noticeably enhanced (mag-fura-2, fura-2) or diminished (magnesium green, fluo-3). The caffeine-induced changes in the fluorescence spectra are clearly distinct from those of metal ion binding at the indicator chelation sites. Binding affinities for calcium of either mag-fura-2 or magnesium green increased only slightly in the presence of caffeine. Caffeine also alters the fluorescence intensities of two other fluorescent dyes lacking a chelation site, fluorescein and sulforhodamine 101, implicating the fluorophore itself as the interaction site for caffeine. In the absence of caffeine, variation of solution hydrophobicity by means of water/dioxane mixtures yielded results similar to those for caffeine. These observations suggest that hydrophobic substances, in general, can alter dye fluorescence in a dye-specific manner. For the particular case of caffeine, and perhaps other commonly used pharmacological agents, the dye interactions can seriously distort fluorescence measurements of intracellular ion concentrations with metal indicator dyes. 相似文献
66.
67.
Cheng AC Coleman RG Smyth KT Cao Q Soulard P Caffrey DR Salzberg AC Huang ES 《Nature biotechnology》2007,25(1):71-75
Lead generation is a major hurdle in small-molecule drug discovery, with an estimated 60% of projects failing from lack of lead matter or difficulty in optimizing leads for drug-like properties. It would be valuable to identify these less-druggable targets before incurring substantial expenditure and effort. Here we show that a model-based approach using basic biophysical principles yields good prediction of druggability based solely on the crystal structure of the target binding site. We quantitatively estimate the maximal affinity achievable by a drug-like molecule, and we show that these calculated values correlate with drug discovery outcomes. We experimentally test two predictions using high-throughput screening of a diverse compound collection. The collective results highlight the utility of our approach as well as strategies for tackling difficult targets. 相似文献
68.
Kenny EE Pe'er I Karban A Ozelius L Mitchell AA Ng SM Erazo M Ostrer H Abraham C Abreu MT Atzmon G Barzilai N Brant SR Bressman S Burns ER Chowers Y Clark LN Darvasi A Doheny D Duerr RH Eliakim R Giladi N Gregersen PK Hakonarson H Jones MR Marder K McGovern DP Mulle J Orr-Urtreger A Proctor DD Pulver A Rotter JI Silverberg MS Ullman T Warren ST Waterman M Zhang W Bergman A Mayer L Katz S Desnick RJ Cho JH Peter I 《PLoS genetics》2012,8(3):e1002559
Crohn''s disease (CD) is a complex disorder resulting from the interaction of intestinal microbiota with the host immune system in genetically susceptible individuals. The largest meta-analysis of genome-wide association to date identified 71 CD–susceptibility loci in individuals of European ancestry. An important epidemiological feature of CD is that it is 2–4 times more prevalent among individuals of Ashkenazi Jewish (AJ) descent compared to non-Jewish Europeans (NJ). To explore genetic variation associated with CD in AJs, we conducted a genome-wide association study (GWAS) by combining raw genotype data across 10 AJ cohorts consisting of 907 cases and 2,345 controls in the discovery stage, followed up by a replication study in 971 cases and 2,124 controls. We confirmed genome-wide significant associations of 9 known CD loci in AJs and replicated 3 additional loci with strong signal (p<5×10−6). Novel signals detected among AJs were mapped to chromosomes 5q21.1 (rs7705924, combined p = 2×10−8; combined odds ratio OR = 1.48), 2p15 (rs6545946, p = 7×10−9; OR = 1.16), 8q21.11 (rs12677663, p = 2×10−8; OR = 1.15), 10q26.3 (rs10734105, p = 3×10−8; OR = 1.27), and 11q12.1 (rs11229030, p = 8×10−9; OR = 1.15), implicating biologically plausible candidate genes, including RPL7, CPAMD8, PRG2, and PRG3. In all, the 16 replicated and newly discovered loci, in addition to the three coding NOD2 variants, accounted for 11.2% of the total genetic variance for CD risk in the AJ population. This study demonstrates the complementary value of genetic studies in the Ashkenazim. 相似文献
69.
70.
Sherman E Itkin A Kuttner YY Rhoades E Amir D Haas E Haran G 《Biophysical journal》2008,94(12):4819-4827
Fluorescence correlation spectroscopy (FCS) is a sensitive analytical tool that allows dynamics and hydrodynamics of biomolecules to be studied under a broad range of experimental conditions. One application of FCS of current interest is the determination of the size of protein molecules in the various states they sample along their folding reaction coordinate, which can be accessed through the measurement of diffusion coefficients. It has been pointed out that the analysis of FCS curves is prone to artifacts that may lead to erroneous size determination. To set the stage for FCS studies of unfolded proteins, we first show that the diffusion coefficients of small molecules as well as proteins can be determined accurately even in the presence of high concentrations of co-solutes that change the solution refractive index significantly. Indeed, it is found that the Stokes-Einstein relation between the measured diffusion coefficient and solution viscosity holds even in highly concentrated glycerol or guanidinium hydrochloride (GuHCl) solutions. These measurements form the basis for an investigation of the structure of the denatured state of two proteins, the small protein L and the larger, three-domain protein adenylate kinase (AK). FCS is found useful for probing expansion in the denatured state beyond the unfolding transition. It is shown that the denatured state of protein L expands as the denaturant concentration increases, in a process akin to the transition from a globule to a coil in polymers. This process continues at least up to 5 M GuHCl. On the other hand, the denatured state of AK does not seem to expand much beyond 2 M GuHCl, a result that is in qualitative accord with single-molecule fluorescence histograms. Because both the unfolding transition and the coil-globule transition of AK occur at a much lower denaturant concentration than those of protein L, a possible correlation between the two phenomena is suggested. 相似文献