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261.
262.
Transcriptional pulsing of a developmental gene 总被引:1,自引:0,他引:1
263.
We have identified a chitinase with antifungal activity in the bulbs of the plant Urginea indica(Indian squill) and purified it about 26-fold. The purified preparation contained a Mr 29 kDa protein that was an active growth inhibitor of the fungal pathogens Fusarium oxysporum and Rhizoctonia solani in an in vitro assay. Amino acid sequence analysis of the Mr 29 kDa protein revealed it to be highly homologous to the family 19 glycoside hydrolases, which are known to possess chitinase activity. The U. indica chitinase lacked a cysteine-rich N-terminal domain (characteristic of class I chitinases) and contained a conserved motif indicative of the signature 1 of family 19 glycoside hydrolases. It shared a approximately 70% sequence identity with the 26 kDa endochitinase of Hordeum vulgare, a typical class II chitinase of family 19. The five cysteines in the partial sequence of the Mr 29 kDa chitinase were found to be identical in location to five of the seven cysteines present in the catalytic domain of the H. vulgare enzyme. The molecular weight, the lack of an N-terminal cysteine-rich sequence, and the striking identity to the H. vulgare endochitinase suggest that the Mr 29 kDa U. indica protein is a putative class II chitinase. The antifungal activity is presumably mediated through the chitinolytic activity of the Mr 29 kDa protein. 相似文献
264.
The motor cortices are active during both movement and movement preparation. A common assumption is that preparatory activity constitutes a subthreshold form of movement activity: a neuron active during rightward movements becomes modestly active during preparation of a rightward movement. We asked whether this pattern of activity is, in fact, observed. We found that it was not: at the level of a single neuron, preparatory tuning was weakly correlated with movement-period tuning. Yet, somewhat paradoxically, preparatory tuning could be captured by a preferred direction in an abstract "space" that described the population-level pattern of movement activity. In fact, this relationship accounted for preparatory responses better than did traditional tuning models. These results are expected if preparatory activity provides the initial state of a dynamical system whose evolution produces movement activity. Our results thus suggest that preparatory activity may not represent specific factors, and may instead play a more mechanistic role. 相似文献
265.
Ronald C. Bernotas Schuyler Antane Rajesh Shenoy Van-Duc Le Ping Chen Boyd L. Harrison Albert J. Robichaud Guo Ming Zhang Deborah Smith Lee E. Schechter 《Bioorganic & medicinal chemistry letters》2010,20(5):1657-1660
Novel 3-(arylsulfonyl)-1-(azacyclyl)-1H-indoles 6 were synthesized as potential 5-HT6 receptor ligands, based on constraining a basic side chain as either a piperidine or a pyrrolidine. Many of these compounds had good 5-HT6 binding affinity with Ki values <10 nM. Depending on substitution, both agonists (e.g., 6o: EC50 = 60 nM, Emax = 70%) and antagonists (6y: IC50 = 17 nM, Imax = 86%) were identified in a 5-HT6 adenylyl cyclase assay. 相似文献
266.
267.
Shreelaxmi Shenoy Asha K. Rajan Muhammed Rashid Viji Pulikkel Chandran Pooja Gopal Poojari Vijayanarayana Kunhikatta Dinesh Acharya Sreedharan Nair Muralidhar Varma Girish Thunga 《PLoS neglected tropical diseases》2022,16(6)
Background and objectiveDifferentiating tropical infections are difficult due to its homogenous nature of clinical and laboratorial presentations among them. Sophisticated differential tests and prediction tools are better ways to tackle this issue. Here, we aimed to develop a clinician assisted decision making tool to differentiate the common tropical infections.MethodologyA cross sectional study through 9 item self-administered questionnaire were performed to understand the need of developing a decision making tool and its parameters. The most significant differential parameters among the identified infections were measured through a retrospective study and decision tree was developed. Based on the parameters identified, a multinomial logistic regression model and a machine learning model were developed which could better differentiate the infection.ResultsA total of 40 physicians involved in the management of tropical infections were included for need analysis. Dengue, malaria, leptospirosis and scrub typhus were the common tropical infections in our settings. Sodium, total bilirubin, albumin, lymphocytes and platelets were the laboratory parameters; and abdominal pain, arthralgia, myalgia and urine output were the clinical presentation identified as better predictors. In multinomial logistic regression analysis with dengue as a reference revealed a predictability of 60.7%, 62.5% and 66% for dengue, malaria and leptospirosis, respectively, whereas, scrub typhus showed only 38% of predictability. The multi classification machine learning model observed to have an overall predictability of 55–60%, whereas a binary classification machine learning algorithms showed an average of 79–84% for one vs other and 69–88% for one vs one disease category.ConclusionThis is a first of its kind study where both statistical and machine learning approaches were explored simultaneously for differentiating tropical infections. Machine learning techniques in healthcare sectors will aid in early detection and better patient care. 相似文献
268.
Isolation of in vitro synthesized covalently closed circular double-stranded DNA by selective denaturation and filtration 总被引:3,自引:0,他引:3
Based upon their resistance to irreversible denaturation, covalently closed circular (CCC) DNA (non-nicked, double-stranded circular molecules) can be purified by alkaline denaturation, neutralization, and filtration through a nitrocellulose membrane. This procedure offers a simple means of isolating in vitro synthesized CCC DNA molecules. The preparations of molecules obtained by this method consisted of 91-97% CCC DNA and contained no detectable inhibitors of biological activity or enzymatic digestion. 相似文献
269.
S. Shetty L. Bharathi K. B. Shenoy S. N. Hegde 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1992,162(7):632-636
Summary The avian juvenile food pigeon milk was studied for its chemical composition and effect on growth in vivo and in vitro. Pigeon milk on a wet weight basis consisted of 9–13% protein, 9–11% fat, 0.9–1.5% carbohydrate, 0.8–1.1% ash, 0.10–0.12% non-protein nitrogen, energy content 5.6–6.8 kcal·g-1. Except for proteins there was little or no decrease in pigeon milk constitutents during the first week of secretion. Pigeon milk proteins consisted of trichloroacetic acid (precipitable), trichloroacetic acid (soluble), and free amino acid components in the ranges 8.4–12.1%, 0.5–0.7% and 1.4–2.5%, respectively; whereas the level of trichloroacetic acid (precipitable) and trichloroacetic acid (soluble) components decreased by about 30%, that of the free amino acids increased by 9% in the first week. About 0.6–1.0% of pigeon milk sugar was found in the trichloroacetic acid (soluble) fraction and increased by 67% in the first week. The remainder was found in the trichloroacetic acid (precipitable) fraction and did not change during this period. Major lipids of pigeon milk were the neutral lipids (7.8–8.4%); the minor lipids were glycolipids (0.9–1.6%), phospholipids (0.5–1.4%) and cholesterol (0.5–0.6%). Squabs fed pigeon milk increased their body weight by 22-fold in the first 3 weeks after hatching, and crude extracts of pigeon milk stimulated the growth of cultured hamster ovary cells. These results reflect the ability of pigeon milk to stimulate growth both in vivo and in vitro.Abbreviations AOAC
association of official analytical chemists
- BRIT
board of radiation and isotope technology
- CHO
chinese hamster ovary
- DNA
deoxyribonucleic acid
- EDTA
ethylenediaminetetra-acetic acid
- FCS
foetal calf serum
- GF
growth factor
- GS
goat serum
- MEM
minimum essential medium
- NPN
nonprotein nitrogen
- PBS
phosphate-buffered saline
- PM
pigeon milk
- TCA(P)
trichloroacetic acid precipitable fraction
- TCA(S)
trichloroacetic acid soluble fraction 相似文献
270.