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31.
Prasanta K. Bordoloi Purnajyoti D. Bhuyan Paran Boruah Manobjyoti Bordoloi Paruchuri G. Rao 《Phytochemistry letters》2009,2(1):22-24
As part of our ongoing programme for isolation of bioactive molecules from the flora of the Indo-Burma biodiversity belt, an unusual long chain alkylated α-methylene-γ-butyrolactone was isolated from the juice of ripe fruit of Artabotrys odoratissimus R.Br. Its structure was determined as 3-methylene-4-pentadecyldihydrofuran-2-one by spectroscopic methods. It was found to have good antifungal activity against Alternaria tenuissima Kunze Ex Pers. isolated from solasodine producing plant Solanum khasianum Clarke. Minimum Inhibitory Concentration (MIC) and IC50 for 3-methylene-4-pentadecyldihydrofuran-2-one were found as 300 and 51.37 μg/ml, respectively. The standard captan was found to have an MIC and IC50 of 200 and 35.52 μg/ml, respectively. 相似文献
32.
Mohammad Sharifur Rahman Ferdous Khan Pinky Karim Syeda Kohji Nishimura Mitsuo Jisaka Tsutomu Nagaya Fumiaki Shono Kazushige Yokota 《Cytotechnology》2014,66(4):635-646
Prostacyclin alternatively called prostaglandin (PG) I2 is an unstable metabolite synthesized by the arachidonate cyclooxygenase pathway. Earlier studies have suggested that prostacyclin analogues can act as a potent effector of adipose differentiation. However, biosynthesis of PGI2 has not been determined comprehensively at different life stages of adipocytes. PGI2 is rapidly hydrolyzed to the stable product, 6-keto-PGF1α, in biological fluids. Therefore, the generation of PGI2 can be quantified as the amount of 6-keto-PGF1α. In this study, we attempted to develop a solid-phase enzyme-linked immunosorbent assay (ELISA) using a mouse antiserum specific for 6-keto-PGF1α. According to the typical calibration curve of our ELISA, 6-keto-PGF1α can be quantified from 0.8 pg to 7.7 ng in an assay. The evaluation of our ELISA revealed the higher specificity of our antiserum without the cross-reaction with other related prostanoids while it exhibited only the cross-reaction of 1.5 % with PGF2α. The resulting ELISA was applied to the quantification of 6-keto-PGF1α generated endogenously by cultured 3T3-L1 cells at different stages. The cultured cells showed the highest capability to generate 6-keto-PGF1α during the maturation phase of 4–6 days, which was consistent with the coordinated changes in the gene expression of PGI synthase and the IP receptor for PGI2. Following these events, the accumulation of fats was continuously promoted up to 14 days. Thus, our immunological assay specific for 6-keto-PGF1α is useful for monitoring the endogenous levels of the unstable parent PGI2 at different life stages of adipogenesis and for further studies on the potential association with the up-regulation of adipogenesis in cultured adipocytes. 相似文献
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Justin R. Ortiz Kathleen M. Neuzil Colin R. Cooke Moni B. Neradilek Christopher H. Goss David K. Shay 《PloS one》2014,9(11)
Background
Studies seeking to estimate the burden of influenza among hospitalized adults often use case definitions that require presence of pneumonia. The goal of this study was to assess the extent to which restricting influenza testing to adults hospitalized with pneumonia could underestimate the total burden of hospitalized influenza disease.Methods
We conducted a modelling study using the complete State Inpatient Databases from Arizona, California, and Washington and regional influenza surveillance data acquired from CDC from January 2003 through March 2009. The exposures of interest were positive laboratory tests for influenza A (H1N1), influenza A (H3N2), and influenza B from two contiguous US Federal Regions encompassing the study area. We identified the two outcomes of interest by ICD-9-CM code: respiratory and circulatory hospitalizations, as well as critical illness hospitalizations (acute respiratory failure, severe sepsis, and in-hospital death). We linked the hospitalization datasets with the virus surveillance datasets by geographic region and month of hospitalization. We used negative binomial regression models to estimate the number of influenza-associated events for the outcomes of interest. We sub-categorized these events to include all outcomes with or without pneumonia diagnosis codes.Results
We estimated that there were 80,834 (95% CI 29,214–174,033) influenza-associated respiratory and circulatory hospitalizations and 26,760 (95% CI 14,541–47,464) influenza-associated critical illness hospitalizations. When a pneumonia diagnosis was excluded, the estimated number of influenza-associated respiratory and circulatory hospitalizations was 24,816 (95% CI 6,342–92,624). The estimated number of influenza-associated critical illness hospitalizations was 8,213 (95% CI 3,764–20,799). Around 30% of both influenza-associated respiratory and circulatory hospitalizations, as well as influenza-associated critical illness hospitalizations did not have pneumonia diagnosis codes.Conclusions
Surveillance studies which only consider hospitalizations that include a diagnosis of pneumonia may underestimate the total burden of influenza hospitalizations. 相似文献35.
Salah Uddin Khan Henrik Salje A. Hannan Md. Atiqul Islam A. A. Mamun Bhuyan Md. Ariful Islam M. Ziaur Rahman Nazmun Nahar M. Jahangir Hossain Stephen P. Luby Emily S. Gurley 《PLoS neglected tropical diseases》2014,8(9)
Background
Japanese encephalitis (JE) virus infection can cause severe disease in humans, resulting in death or permanent neurologic deficits among survivors. Studies indicate that the incidence of JE is high in northwestern Bangladesh. Pigs are amplifying hosts for JE virus (JEV) and a potentially important source of virus in the environment. The objectives of this study were to describe the transmission dynamics of JEV among pigs in northwestern Bangladesh and estimate the potential impact of vaccination to reduce incidence among pigs.Methodology/Principal Findings
We conducted a comprehensive census of pigs in three JE endemic districts and tested a sample of them for evidence of previous JEV infection. We built a compartmental model to describe JEV transmission dynamics in this region and to estimate the potential impact of pig vaccination. We identified 11,364 pigs in the study area. Previous JEV infection was identified in 30% of pigs with no spatial differences in the proportion of pigs that were seropositive across the study area. We estimated that JEV infects 20% of susceptible pigs each year and the basic reproductive number among pigs was 1.2. The model suggest that vaccinating 50% of pigs each year resulted in an estimated 82% reduction in annual incidence in pigs.Conclusions/Significance
The widespread distribution of historic JEV infection in pigs suggests they may play an important role in virus transmission in this area. Future studies are required to understand the contribution of pig infections to JE risk in humans and the potential impact of pig vaccination on human disease. 相似文献36.
Rashi Verma Monika Yadav Rajabrata Bhuyan Shweta Aggarwal Arnab Nayek 《Journal of receptor and signal transduction research》2016,36(6):601-616
Computer-aided antibody engineering has been successful in the design of new biologics for disease diagnosis and therapeutic interventions. Interleukin-6 (IL-6), a well-recognized drug target for various autoimmune and inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, and psoriasis, was investigated in silico to design potential lead antibodies. Here, crystal structure of IL-6 along with monoclonal antibody olokizumab was explored to predict antigen–antibody (Ag???Ab)-interacting residues using DiscoTope, Paratome, and PyMOL. Tyr56, Tyr103 in heavy chain and Gly30, Ile31 in light chain of olokizumab were mutated with residues Ser, Thr, Tyr, Trp, and Phe. A set of 899 mutant macromolecules were designed, and binding affinity of these macromolecules to IL-6 was evaluated through Ag???Ab docking (ZDOCK, ClusPro, and Rosetta server), binding free-energy calculations using Molecular Mechanics/Poisson Boltzman Surface Area (MM/PBSA) method, and interaction energy estimation. In comparison to olokizumab, eight newly designed theoretical antibodies demonstrated better result in all assessments. Therefore, these newly designed macromolecules were proposed as potential lead antibodies to serve as a therapeutics option for IL-6-mediated diseases. 相似文献
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38.
Regioselective synthesis of novel steroidal anti-inflammatory ante drug analogues, viz., [16alpha,17alpha-d]-isoxazolines 1(a-h) and 2(a-h) prepared in a single step in good yield by the reaction of 16-dehydropregnenolone acetate (16-DPA) 1 or related 21-chloro-20-oxopregnane 2 with various aldoximes (a-h) in presence of chloramine-T in refluxing ethanol. 相似文献
39.
Rajabrata Bhuyan 《Journal of biomolecular structure & dynamics》2017,35(2):380-398
The voltage gated Kv1.5 channels conduct the ultrarapid delayed rectifier current (IKur) and play critical role in repolarization of action potential duration. It is the most rapidly activated channel and has very little or no inactivated states. In human cardiac cells, these channels are expressed more extensively in atrial myocytes than ventricle. From the evidences of its localization and functions, Kv1.5 has been declared a selective drug target for the treatment of atrial fibrillation (AF). In this present study, we have tried to identify the rapidly activating property of Kv1.5 and studied its mode of inhibition using molecular modeling, docking, and simulation techniques. Channel in open conformation is found to be stabilized quickly within the dipalmitoylphosphatidylcholine membrane, whereas most of the secondary structure elements were lost in closed state conformation. The obvious reason behind its ultra-rapid property is possibly due to the amino acid alteration in S4–S5 linker; the replacement of Lysine by Glutamine and vice versa. The popular published drugs as well as newly identified lead molecules were able to inhibit the Kv1.5 in a very similar pattern, mainly through the nonpolar interactions, and formed sable complexes. V512 is found as the main contributor for the interaction along with the other important residues such as V505, I508, A509, V512, P513, and V516. Furthermore, two screened novel compounds show surprisingly better inhibitory potency and can be considered for the future perspective of antiarrhythmic survey. 相似文献
40.