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81.
Cystoid oedema of macula is the most frequent problem following non-complicated cataract surgery, which leads to weakening of visual acutity. We have studied the treatment outcomes of the topical therapy with corticosteroids and nonsteroid antirheumatics during prospective randomized study in comparison with orally applied acethazolamide. However, 8 weeks later in treatment was observed a positive effect in both groups, on the eyes of patients, treated with acetazolamide, resorption of the oedema was faster, more intensive and ultimate visual acutity was statistically significantly better. Results demonstrated a benefit of combined therapy with antiinflamative drugs and orally prescribed acetazolamide in pseudophakic macular oedema. 相似文献
82.
Jukić T Katusić D Cikara I Kordić R Sikić J Vukojević N Sarić B 《Collegium antropologicum》2005,29(Z1):75-79
The aim of the present study is to evaluate the potential statistically significant differences in the ocular blood flow parameters in eyes with rhegmatogenous retinal detachment (RD). Eleven patients, 5 females and 6 males, mean age 46 years (range 22-70), with the unilateral rhegmatogenous RD were enrolled in the study. Colour Doppler Ultrasound was used to measure ocular blood flow velocities in the ophthalmic artery (OA), posterior ciliary's arteries (PCA) and ophthalmic vein (OV). The contralateral eye served as a control. All Doppler examinations were performed 1 day before and exactly 3 days after the retinal detachment surgery. The measurements of the peak systolic velocity (Vmax), diastolic velocity (Vd), minimum velocity (Vmin), time-averaged velocity (TAV), resistive index (RI) and pulsatility index (PI) showed no statistically significant difference (by paired Student's t-test, p > 0.05) between the OA, PCA and OV in healthy eyes and eyes with RD before operation, as well as between the eyes with RD before and after the operation. Only was increased RI in OV of eyes with RD after the surgery (p < 0.05). All these parameters were not related with 2 or more quadrants of RD, but the difference in duration of retinal detachment in days is statistically significant (by Wilcoxon t-test p > 0.05). Pearson correlation method gave statistically significant correlation between RI and PI of the OA in healthy eyes (r = 0.826, p < 0.01), eyes with RD before operation (r = 0.847, p < 0.01) and eyes with RD after the operation (r = 0.856, p < 0.01). Formula for the calculation of PI by RI was derived using linear regression analysis in all three cases. Scleral buckling surgery leaves the ocular blood parameters in OA unchanged. The correlation between RD and logarithm of duration of RD in days is statistically significant. 相似文献
83.
Selenocysteine tRNA-specific elongation factor SelB is a structural chimaera of elongation and initiation factors
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In all three kingdoms of life, SelB is a specialized translation elongation factor responsible for the cotranslational incorporation of selenocysteine into proteins by recoding of a UGA stop codon in the presence of a downstream mRNA hairpin loop. Here, we present the X-ray structures of SelB from the archaeon Methanococcus maripaludis in the apo-, GDP- and GppNHp-bound form and use mutational analysis to investigate the role of individual amino acids in its aminoacyl-binding pocket. All three SelB structures reveal an EF-Tu:GTP-like domain arrangement. Upon binding of the GTP analogue GppNHp, a conformational change of the Switch 2 region in the GTPase domain leads to the exposure of SelB residues involved in clamping the 5' phosphate of the tRNA. A conserved extended loop in domain III of SelB may be responsible for specific interactions with tRNA(Sec) and act as a ruler for measuring the extra long acceptor arm. Domain IV of SelB adopts a beta barrel fold and is flexibly tethered to domain III. The overall domain arrangement of SelB resembles a 'chalice' observed so far only for initiation factor IF2/eIF5B. In our model of SelB bound to the ribosome, domain IV points towards the 3' mRNA entrance cleft ready to interact with the downstream secondary structure element. 相似文献
84.
85.
Alexey Y Yukin Mohamed Helmy J Christopher Hennings Juha Voipio Nenad Šestan Christian A Hübner Kai Kaila 《The EMBO journal》2013,32(16):2275-2286
Brain carbonic anhydrases (CAs) are known to modulate neuronal signalling. Using a novel CA VII (Car7) knockout (KO) mouse as well as a CA II (Car2) KO and a CA II/VII double KO, we show that mature hippocampal pyramidal neurons are endowed with two cytosolic isoforms. CA VII is predominantly expressed by neurons starting around postnatal day 10 (P10). The ubiquitous isoform II is expressed in neurons at P20. Both isoforms enhance bicarbonate‐driven GABAergic excitation during intense GABAA‐receptor activation. P13–14 CA VII KO mice show behavioural manifestations atypical of experimental febrile seizures (eFS) and a complete absence of electrographic seizures. A low dose of diazepam promotes eFS in P13–P14 rat pups, whereas seizures are blocked at higher concentrations that suppress breathing. Thus, the respiratory alkalosis‐dependent eFS are exacerbated by GABAergic excitation. We found that CA VII mRNA is expressed in the human cerebral cortex before the age when febrile seizures (FS) occur in children. Our data indicate that CA VII is a key molecule in age‐dependent neuronal pH regulation with consequent effects on generation of FS. 相似文献
86.
The cell interior is in constant movement, which is to a large extent determined by microtubules, thin and long filaments that permeate the cytoplasm. To move large objects, microtubules need to connect them to the site of their destination. For example, during cell division, microtubules connect chromosomes with the spindle poles via kinetochores, protein complexes on the chromosomes. A general question is how microtubules, while being bound to one structure, find the target that needs to be connected to this structure. Here we review the mechanisms of how microtubules search for kinetochores, with emphasis on the recently discovered microtubule feature to explore space by pivoting around the spindle pole. In addition to accelerating the search for kinetochores, pivoting helps the microtubules to search for cortical anchors, as well as to self-organize into parallel arrays and asters to target specific regions of the cell. Thus, microtubule pivoting constitutes a mechanism by which they locate targets in different cellular contexts. 相似文献
87.
Marković ZS Dimitrić Marković JM Milenković D Filipović N 《Journal of molecular modeling》2011,17(10):2575-2584
Density functional theory calculations were performed to evaluate the antioxidant activity of baicalein. The conformational
behaviors of both the isolated and the aqueous-solvated species (simulated with the conductor-like polarizable continuum solvation
model) were analyzed at the M052X/6-311 + G(d,p) level. The most stable tautomers of various forms of baicalein displayed
three IHBs between O4 and OH5, O5 and OH6, and O6 and OH7. The most stable tautomer of the baicalein radical was obtained
by dehydrogenating the hydroxyl at C6, while the most stable anion tautomer was obtained by deprotonating the C7 hydroxyl
in gaseous and aqueous phases. The expected antioxidant activity of baicalein was explained by its ionization potentials (IPs)
and homolytic O–H bond dissociation enthalpies (BDEs), which were obtained via the UM052X optimization level of the corresponding
radical species. Heterolytic O–H bond cleavages (proton dissociation enthalpies, PDEs) were also computed. The calculated
IP, BDE, and PDE values suggested that one-step H-atom transfer, rather than sequential proton loss–electron transfer or electron
transfer–proton transfer, would be the most favorable mechanism for explaining the antioxidant activity of baicalein in the
gas phase and in nonpolar solvents. In aqueous solution, the SPLET mechanism was more important. 相似文献
88.
Aysu Yarman Lei Peng Yunhua Wu Amay Bandodkar Nenad Gajovic-Eichelmann Ulla Wollenberger Martin Hofrichter René Ullrich Katrin Scheibner Frieder W. Scheller 《Bioanalytical reviews》2011,3(2-4):67-94
Aromatic peroxygenase (APO) from the basidiomycetous mushroom Agrocybe aegerita (AaeAPO) and microperoxidases (MPs) obtained from cytochrome c exhibit a broad substrate spectrum including hydroxylation of selected aromatic substrates, demethylation and epoxidation by means of hydrogen peroxide. It overlaps with that of cytochrome P450 (P450), making MPs and APOs to alternate recognition elements in biosensors for the detection of typical P450 substrates. Here, we discuss recently developed approaches using microperoxidases and peroxygenases in view of their potential to supplement P450 enzymes as recognition elements in biosensors for aromatic compounds. Starting as early as the 1970s, the direct electron transfer between electrodes and the heme group of heme peptides called microperoxidases has been used as a model of oxidoreductases. These MP-modified electrodes are used as hydrogen peroxide detectors based on the catalytic current generated by electrically contacted microperoxidase molecules. A similar catalytic reaction has been obtained for the electrode-immobilised heme protein AaeAPO. However, up to now, no MP-based sensors for substrates have been described. In this review, we present biosensors which indicate 4-nitrophenol, aniline, naphthalene and p-aminophenol based on the peroxide-dependent substrate conversion by electrode-immobilised MP and AaeAPO. In these enzyme electrodes, the signal is generated by the conversion of all substrates, thus representing in complex media an overall parameter. The performance of these sensors and their further development are discussed in comparison with P450-based electrodes. 相似文献
89.
90.
Farid Radmanesh Ahmet?Okay Caglayan Jennifer?L. Silhavy Cahide Yilmaz Vincent Cantagrel Tarek Omar Ba?ak Rosti Hande Kaymakcalan Stacey Gabriel Mingfeng Li Nenad ?estan Kaya Bilguvar William?B. Dobyns Maha?S. Zaki Murat Gunel Joseph?G. Gleeson 《American journal of human genetics》2013,92(3):468-474
Cobblestone brain malformation (COB) is a neuronal migration disorder characterized by protrusions of neurons beyond the first cortical layer at the pial surface of the brain. It is usually seen in association with dystroglycanopathy types of congenital muscular dystrophies (CMDs) and ocular abnormalities termed muscle-eye-brain disease. Here we report homozygous deleterious mutations in LAMB1, encoding laminin subunit beta-1, in two families with autosomal-recessive COB. Affected individuals displayed a constellation of brain malformations including cortical gyral and white-matter signal abnormalities, severe cerebellar dysplasia, brainstem hypoplasia, and occipital encephalocele, but they had less apparent ocular or muscular abnormalities than are typically observed in COB. LAMB1 is localized to the pial basement membrane, suggesting that defective connection between radial glial cells and the pial surface mediated by LAMB1 leads to this malformation. 相似文献