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41.
Lidocaine effects in the spinal cord have been extensively investigated over the years. Although the intrathecal route is usually used to treat insults occurring in the spinal cord, the local delivery drug via intraparenchymal infusions has gained increasing favor for the treatment of some neurodegenerative disorders. The aim of the present study was to evaluate the behavioral and tissue effects of the intraparenchymal injection of different concentrations of lidocaine into the rat cervical spinal cord. Young male Sprague–Dawley rats were intraparenchymally injected with 0.5%, 1% or 2% lidocaine at the C5 segment of the spinal cord. Other rats were injected with saline solution (sham group). Hot plate test was determined at 0, 1, 2, 3, 7 and 14 post-injection (pi) days. Rats of each experimental group were euthanized either at 1, 2, 3, 7 or 14 pi days. Intact animals were used as controls. Sections of the C5 segment were used for histological, immunohistochemical or immunofluorescence analysis. Injection of 0.5% lidocaine did not affect neuronal counting, did not evoke an inflammatory reaction, nor induce astrocyte activation. Therefore, a concentration of 0.5% lidocaine is suggested to promote anti-inflammatory effects after injury.  相似文献   
42.
The aim of the present study was to evaluate the effectiveness of chlorhexidine digluconate (CHX) and commonly used mouthrinses to single- and poly-species biofilms by S. mutans, S. aureus and P. aeruginosa, on titanium discs of grade IV. The formation of single- and poly-species biofilms at 16.5, 40.5 and 64.5-h incubation on titanium surface was evaluated by plate count (CFU ml−1) before and after exposure to CHX and four mouthrinses (Curasept, Listerine, Meridol and Buccagel) and expressed as percentage of Inhibitory Activity (IA%). The application of the different anti-plaque formulations on biofilm can reduce the adhesion of bacteria to titanium surface with different degrees. The higher efficacy was observed for Listerine that shows IA% = 100 on the biofilm formed by S. mutans at 16.5 h. Log count of CFU was dependent to culture time and four mouthrinses for S. mutans and S. aureus, whilst was not dependent to culture time but to mouthrinses for P. aeruginosa. In general, the efficacy was particularly lesser to poly-species biofilms; no statistical differences were evidenced between all the mouthrinses and CHX as control group. The tested mouthrinses, compared to reference CHX 0.2%, have demonstrated a significant lower antibacterial activity than Listerine towards the experimental biofilms. This “in vitro” biofilm model should prove extremely useful for pre-clinical testing of anti-plaque agents, which inhibit biofilm formation, can prevent subsequent implant failure.  相似文献   
43.
The changes in nuclear morphology (karyometry) and DNA content in prostatic intraepithelial neoplasia (PIN) were analyzed on tissue sections. The cases of PIN were subdivided into PIN 1 and PIN 2 based on the degree of proliferation and the anaplasia of the secretory cells lining the ducts and acini. Cases of nodular hyperplasia (NH) and adenocarcinoma were also studied for comparative purposes. Karyometric analysis showed a progression of most values from NH to PIN to carcinoma. The DNA analysis showed a decrease in the frequency of nuclei in the diploid range and an increase in the percentage of nuclei in the other ploidy regions (especially between 2c and 4c and in the tetraploid range) from NH to PIN to carcinoma. Forward stepwise discriminant analysis showed similarities between NH and PIN 1 and between PIN 2 and carcinoma. These findings suggest that the evolution towards adenocarcinoma is characterized by progressive morphologic derangements of the nuclei and by the transformation of the diploid DNA content into a nondiploid one, with the changes taking place at the level of PIN 2.  相似文献   
44.
This study investigated the effects of maternal separation in C57BL/6 male and female mice during infancy on later adult fear and anxiety behaviors. Additionally, we observed the maternal behavior of the dams to examine aspects of maternal care that may be modulated by daily bouts of separation. In males, mice that experienced maternal separation during the neonatal period displayed significantly higher levels of anxiety and fear behavior, as measured by the open field test and elevated plus maze, compared to control, standard facility reared males. In females, however, maternal separation reduced anxiety and fear behavior in the open field test, but only when the females were in the diestrous phase of their estrous cycle. The 30-min daily observation of the dams revealed that the separation did not significantly alter the frequency of the maternal care provided by the dam at the time point measured. These results indicate that the emotionality of adult male and female mice can be modulated by maternal separation. However, this effect is dependent on the sex of the offspring and the phase of the estrous cycle of the female.  相似文献   
45.
Chromium(VI) was reduced by Thiobacillus ferrooxidans grown with elemental sulphur as the sole energy source. Chromium(VI) reduction (as high as 2000 M), was due to the presence of sulphite and thiosulphate, among others with high reducing power which was generated during the sulphur oxidation by the bacteria. Therefore, Thiobacillus ferrooxidans could be used to treat chromium(VI)-containing industrial effluents.  相似文献   
46.
Two novel gadolinium(III) chelates based on the structure of the heptadentate macrocyclic 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) ligand have been synthesized and their relaxometric and luminescent properties thoroughly investigated. They contain two water molecules in the inner coordination sphere in fast exchange with the bulk solvent and bear either a p-bromobenzyl or a p-phosphonatomethylbenzanilido substituent for promoting further interaction with macromolecular substrates. Upon interaction with human serum albumin the expected relaxation enhancement is not observed owing to displacement of the two inner-sphere water molecules of the complexes by a donor atom (likely from a carboxylate group) on the protein and possibly the phosphate anion of the buffered solution, respectively. We modeled the observed behavior by measuring the decrease of the relaxation rate of the water protons upon addition of malonate anion to aqueous solutions of the complexes. Conversely, no change in the hydratation state of the Gd(III) center for both complexes has been observed when the substrate for the formation of the macromolecular adduct is represented by poly-beta-cyclodextrin.  相似文献   
47.
X-ray photoelectron spectroscopy (XPS) was applied to a solid-state investigation on adsorbed systems obtained by contacting different samples of an activated carbon (Chemviron Filtrasorb 400) with solutions containing (a) 1,10-phenanthroline (phen); (b) NiCl2·6H2O. (c) Ni2+ ions and phen in a 1:3 molar ratio.XPS results on these systems are discussed with particular regard to the chemical state of the ligand (interaction of functional groups with the substrate) and of the metal ions on carbon (assessment of Ni oxidation state; detection of Ni complexes on carbon and information on their stoichiometries and structures). Various effects of successive chemical treatments on the above reported carbon species were also revealed by XPS, such as:(i) the formation of a ‘carbon–ligand’ system (activated carbon with ligand firmly present on it) after acid elution of the activated carbon treated with Ni–phen complexes in solution, and (ii) the adsorption of Ni2+ ions on this ‘carbon–ligand’ system, with fomation of Ni–phen complexes on carbon.  相似文献   
48.
Two genetically related strains of Tuber borchii Vittad. (1BO and 43BO) produce mycorrhizas with Tilia platyphyllos Scop. with a different degree of efficiency. The aim of this work was to characterize the morphology of the fungal symbiotic structures in order to examine potential relationships between the anatomical traits of the mycorrhiza, the mycorrhizal capacities of the fungal strains and their effect on the host plants. Some morphological features of mantle hyphae (small size, intense staining, vacuolization, abundance of mitochondria) led to a mantle with morphological features that were isolate-specific. There were unexpected differences, at least under our experimental conditions: 1BO strain mantle cells were larger, less reactive to staining, more highly vacuolated and poorer in mitochondria than those of 43BO. These features were found throughout the mantle in 1BO, while the inner mantle hyphae of 43BO were significantly smaller and more intensely stained than the outer cells. In the 43BO strain there was a positive relation between these features and higher infectivity (evaluated as percentage of mycorrhizal tips) as well as a slightly more effective stimulation of plant growth. These observations suggest that genetically related truffle strains produce mycorrhizas with different morphologies, which may be related to a more efficient response of the host plant to inoculation.  相似文献   
49.
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