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Covalent coupling of lipid to protein antigen, BSA, modifies the immunogenicity leading to selective induction of delayed type hypersensitivity in mice with no or very little concomitant antibody production. The mode of linkage of lipid to protein, however, controls its tissue distribution and retention in the body and cell uptake in vitro. Whereas D-BSA accumulates in the draining lymph node after foot pad inoculation, DA-BSA stays at the site. Further, DA-BSA is eliminated much more slowly and D-BSA more quickly from the body than the native antigen. Although both lipid-conjugates are taken up by lymphoid cells in vitro more than the native antigen, DA-BSA binds significantly more than D-BSA. On the basis of in vitro blastogenic response and enumeration of antigen sensitive cells and in vivo tests of delayed type hypersensitivity, DA-BSA appears superior to D-BSA but neither was as potent as BSA in CFA. 相似文献
73.
Viacheslav N. Kachalov Huyen Nguyen Suraj Balakrishna Luisa Salazar-Vizcaya Rami Sommerstein Stefan P. Kuster Anthony Hauser Pia Abel zur Wiesch Eili Klein Roger D. Kouyos 《PLoS computational biology》2021,17(1)
Beta-lactam- and in particular carbapenem-resistant Enterobacteriaceae represent a major public health threat. Despite strong variation of resistance across geographical settings, there is limited understanding of the underlying drivers. To assess these drivers, we developed a transmission model of cephalosporin- and carbapenem-resistant Klebsiella pneumoniae. The model is parameterized using antibiotic consumption and demographic data from eleven European countries and fitted to the resistance rates for Klebsiella pneumoniae for these settings. The impact of potential drivers of resistance is then assessed in counterfactual analyses. Based on reported consumption data, the model could simultaneously fit the prevalence of extended-spectrum beta-lactamase-producing and carbapenem-resistant Klebsiella pneumoniae (ESBL and CRK) across eleven European countries over eleven years. The fit could explain the large between-country variability of resistance in terms of consumption patterns and fitted differences in hospital transmission rates. Based on this fit, a counterfactual analysis found that reducing nosocomial transmission and antibiotic consumption in the hospital had the strongest impact on ESBL and CRK prevalence. Antibiotic consumption in the community also affected ESBL prevalence but its relative impact was weaker than inpatient consumption. Finally, we used the model to estimate a moderate fitness cost of CRK and ESBL at the population level. This work highlights the disproportionate role of antibiotic consumption in the hospital and of nosocomial transmission for resistance in gram-negative bacteria at a European level. This indicates that infection control and antibiotic stewardship measures should play a major role in limiting resistance even at the national or regional level. 相似文献
74.
Melissa Carrillo Suraj Pandey Juan Sanchez Moraima Noda Ishwor Poudyal Luis Aldama Tek Narsingh Malla Elin Claesson Weixiao Yuan Wahlgren Denisse Feliz Vukica Šrajer Michał Maj Leticia Castillon So Iwata Eriko Nango Rie Tanaka Tomoyuki Tanaka Luo Fangjia Marius Schmidt 《Structure (London, England : 1993)》2021,29(7):743-754.e4
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A new class of antenna chromophores so called ‘tetrazolates’ have not been explored much for lanthanide luminescencent complexes. However, we have already published several articles considering pyridineoxide tetrazolates as sensitizer with lanthanide ions. Although this class of antenna attracted much less attention because of its poor photoluminescence quantum yields (tris‐pyridineoxide tetrazolate europium complex = 13% in solution) we tried and successfully achieved to improve the photoluminescence quantum yields for this particular antenna molecule by replacing coordinated water from the inner coordination sphere of europium ion by introducing phosphine oxides as additional chromophore. In the present article the two bis‐phosphine oxides attach two molecules of tris‐pyridineoxide tetrazolate europium(III) complex which leads to the improvement of the overall molar absorption coefficients as well as photo‐physical properties of the complexes. We found more than two‐fold increase (31% in solution) in photoluminescence quantum yield with one of the coordinated phosphine oxides comparing with that of tris‐pyridineoxide tetrazolate europium(III) complex. 相似文献
77.
The effects of urea and glycine-betaine (GB) osmolytes on the hydrophobic interactions of neopentane in water have been studied using molecular dynamics simulations. From the study of the potentials of mean force, it is observed that both urea and GB decrease the association and solvation of neopentane. The calculated equilibrium constants show that urea and GB decrease the population of solvent-separated minima of neopentane. The hydrophobic association as well as solvation of neopentane molecules are stabilised by entropy and enthalpy in the mixtures. The radial distribution functions (RDFs) and running coordination numbers of water, urea and GB molecules show that neopentane shows salting-in behaviour in aqueous-GB, aqueous-urea and aqueous-urea-GB mixtures. Neopentane is preferentially solvated by GB in aqueous-GB and preferentially solvated by urea in aqueous-urea-GB solutions. The preferential solvation of neopentane by GB suggests that GB decreases the interaction between neopentane molecules i.e. salting-in of neopentane. The calculated solvation free energies and radial density profiles of neopentane also support the salting-in behaviour of neopentane in the mixtures of these osmolytes. 相似文献
78.
L. Nivethitha A. Mooventhan N. K. Manjunath Lokesh Bathala Vijay K. Sharma 《Applied psychophysiology and biofeedback》2018,43(1):87-92
Various pranayama techniques are known to produce different physiological effects. We evaluated the effect of three-different pranayama techniques on cerebrovascular hemodynamics. Eighteen healthy volunteers with the mean?±?standard deviation age of 23.78?±?2.96 years were performed three-different pranayama techniques: (1) Bhramari, (2) Kapalbhati and (3) Bahir-Kumbhaka in three-different orders. Continuous transcranial Doppler (TCD) monitoring was performed before, during and after the pranayama techniques. TCD parameters such as peak systolic velocity, end diastolic velocity (EDV), mean flow velocity (MFV) and pulsatility index (PI) of right middle cerebral artery were recorded. Practice of Kapalbhati showed significant reductions in EDV and MFV with significant increase in PI while, Bahir-Kumbhaka showed significant increase in EDV and MFV with significant reduction in PI. However, no such significant changes were observed in Bhramari pranayama. Various types of pranayama techniques produce different cerebrovascular hemodynamic changes in healthy volunteers. 相似文献
79.
A. Desai K. Murali-Krishna B. Ramireddy V. Ravi R. Manjunath 《Journal of biosciences》1997,22(1):33-45
Japanese encephalitis virus (JEV) is a positive stranded RNA virus that belongs to the flavivirus group. JEV infection damages
the central nervous system (CNS) and is one of the main causative agents of acute encephalitis. H-2 restricted virus-specific
cytotoxic T lymphocytes (CTL) have been generated specifically against JEV in our laboratory and these CTL have been shown
to protect mice against lethal challenge with JEV. Virus replication was found to be inhibited in the brains of animals that
were adoptively transferred with JEV specific CTL as revealed by immunohistological staining as well as viral plaque assays.
We further show that virus specific CTL could be recovered from such protected mice as long as 45 days after adoptive transfer. 相似文献
80.