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1.
This study aimed to investigate the protective effects of arbutin (ARB) against brain injury induced in rats with potassium bromate (KBrO3). The rats were divided into four groups as Group 1: Control (0.9% NaCl ml/kg/day p.), Group 2: KBrO3 (100 mg/kg (gavage), Group 3: ARB (50 mg/kg/day p.), and Group 4: KBrO3 + ARB (100 mg/kg (gavage) + 50 mg/kg/day p.). At the end of the fifth day of the study, the rats in all groups were killed, and their brain tissues were collected. In the collected brain tissues, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured, and routine histopathological examinations were made. The MDA levels in the group that was exposed to KBrO3 were significantly higher than those in the control group (p ˂ 0.001). In comparison to the KBrO3 group, the MDA levels in the KBrO3 + ARB group were significantly lower (p ˂ 0.001). It was observed that SOD and CAT enzyme activity levels were significantly lower in the KBrO3 group compared to the control group (p ˂ 0.001), while these levels were significantly higher in the KBrO3 + ARB group than in the KBrO3 group (p ˂ 0.001). Additionally, the group that was subjected to KBrO3 toxicity, as well as ARB administration, had much lower levels of histopathologic signs than the group that was subjected to KBrO3 toxicity only. Consequently, it was found that KBrO3 exposure led to injury in the brain tissues of the rats, and using ARB was effective in preventing this injury.  相似文献   
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Numerical prediction of non-Newtonian blood flow in a 3D abdominal aortic aneurysm bifurcating model is carried out. The non-Newtonian Carreau model is used to characterise the shear thinning behaviour of the human blood. A physical inlet velocity waveform incorporating a radial velocity distribution reasonably representative of a practical case configuration is employed. Case studies subject to both equal and unequal outlet pressures at iliac bifurcations are presented to display convincingly the downstream pressure influences on the flow behaviour within the aneurysm. Simulations indicate that the non-Newtonian aspects of the blood cannot at all be neglected or given a cursory treatment. The wall shear stress (WSS) is found to change significantly at both the proximal and distal ends of the aneurysm. At the peak systole, the WSS is peak around the bifurcation point, whereas the WSS becomes zero in the bifurcation point. Differential downstream pressure fields display significant effects regarding the flow evolution in the iliac arteries, whereas little or no effects are observed directly on the flow details in the aneurysm.  相似文献   
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The enzyme carbonic anhydrase (E.C. 4.2.1.1) has a stimulatory effect on glaucoma, an eye disease that has a risk to dogs, which are models for the human eye disease, that is similar to that in humans.

In this study, some sulfonamide derivatives, 2-(3-cyclohexene-1-carbamido)-1,3,4-thiadiazole-5-sulfonamide (CCTS), 4-(3-cyclohexene-1-carbamido) methyl-benzenesulfonamide (CCBS), 2-(9-octadecenoylamido)-1,3,4-thiadiazole-5-sulfonamide (ODTS), 2-(4,7,10-trioxa-tetradecanoylamido)-1,3,4-thiadiazole-5-sulfonamide (TDTS), and 2-(8-methoxycoumarine-3-carbamido)-1,3,4-thiadiazole-5-sulfonamide (MCTS), as well as some anionic compounds (perchlorate and chloride) and existing medicines (dorzolamide-HCl, gentamicine sulphate, tropicamide, and procaine-HCl) were assayed for their inhibition of dog carbonic anhydrase (dCA), which was purified from erythrocytes on an affinity gel of L-tyrosine-sulfonamide-Sepharose 4B. ODTS showed the highest potency amongst the synthetic compounds with IC50 value 1.18 × 10? 5 M. Amongst the medicines tested, only dorzolamide showed inhibition with IC50 value 5.05 × 10? 4 M. Procaine and tropicamide actually showed an activatory effect, whereas gentamicine sulfate had no significant effect. The inhibitory effects of anionic compounds such as perchlorate and chloride were also investigated; whereas perchlorate showed inhibition, chloride did not.  相似文献   
4.
We hypothesized that solid tumors rarely occur in patients with hydatid disease. We obtained the serum of 14 patients diagnosed with hydatid disease, the serum of 10 patients who did not have a history of hydatid disease, and the hydatid cyst fluid from six patients. These sera and fluid samples were added at different concentrations to NCI-H209/An1 human lung small cell carcinoma cells and L929 mouse fibroblasts as a control group. Sera of patients with hydatid diseases had cytotoxic effects on NCI-H209/An1 cells, but they did not have cytotoxic effects on fibroblast cells. Sera from healthy subjects did not have a cytotoxic effect on the tumor cell line or control fibroblasts. Cyst fluid, also, did not have toxic effects on the NCI-H209/An1 cell line, but was toxic to fibroblasts up to a 1:32 dilution. Sera from patients with hydatid disease had cytotoxic effects on human small cell lung cancer cells in vitro.  相似文献   
5.
Starting in 1991, the advance of Tyr-recombinases Flp and Cre enabled superior strategies for the predictable insertion of transgenes into compatible target sites of mammalian cells. Early approaches suffered from the reversibility of integration routes and the fact that co-introduction of prokaryotic vector parts triggered uncontrolled heterochromatization. Shortcomings of this kind were overcome when Flp-Recombinase Mediated Cassette Exchange entered the field in 1994. RMCE enables enhanced tag-and-exchange strategies by precisely replacing a genomic target cassette by a compatible donor construct. After “gene swapping” the donor cassette is safely locked in, but can nevertheless be re-mobilized in case other compatible donor cassettes are provided (“serial RMCE”). These features considerably expand the options for systematic, stepwise genome modifications. The first decade was dominated by the systematic generation of cell lines for biotechnological purposes. Based on the reproducible expression capacity of the resulting strains, a comprehensive toolbox emerged to serve a multitude of purposes, which constitute the first part of this review. The concept per se did not, however, provide access to high-producer strains able to outcompete industrial multiple-copy cell lines. This fact gave rise to systematic improvements, among these certain accumulative site-specific integration pathways. The exceptional value of RMCE emerged after its entry into the stem cell field, where it started to contribute to the generation of induced pluripotent stem (iPS-) cells and their subsequent differentiation yielding a variety of cell types for diagnostic and therapeutic purposes. This topic firmly relies on the strategies developed in the first decade and can be seen as the major ambition of the present article. In this context an unanticipated, potent property of serial Flp-RMCE setups concerns the potential to re-open loci that have served to establish the iPS status before the site underwent the obligatory silencing process. Other relevant options relate to the introduction of composite Flp-recognition target sites (“heterospecific FRT-doublets”), into the LTRs of lentiviral vectors. These “twin sites” enhance the safety of iPS re-programming and -differentiation as they enable the subsequent quantitative excision of a transgene, leaving behind a single “FRT-twin”. Such a strategy combines the established expression potential of the common retro- and lentiviral systems with options to terminate the process at will. The remaining genomic tag serves to identify and characterize the insertion site with the goal to identify genomic “safe harbors” (GOIs) for re-use. This is enabled by the capacity of “FRT-twins” to accommodate any incoming RMCE-donor cassette with a compatible design.  相似文献   
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This study tested the spatial variations in the digestive/intestine tract length of Capoeta banarescui, with regard to their diets in different habitats. Highly varied diets observed in a previous study within the same river system posed the question whether this flexibility is reflected in the digestive tract and intestine length of the species in the Ye?il?rmak River, Turkey. Totals of 382 specimens (standard length 4.6–19.1 cm) were captured by electro‐fishing along the river in September 2012 at 11 locations spanning elevations from 34 to 992 m. The stomach, intestine and total digestive tract lengths were measured, and stomach contents analysed from 196 specimens. For statistical analyses, the stomach, intestine and total digestive tract length were expressed as percentages of total weight and standard length. The data provided evidence that the digestive tract and intestine lengths varied significantly among locations in association with the diet. Fish having dominantly carnivorous diets (e.g. chironomid larvae/invertebrates) in two locations had significantly shorter intestines and digestive tracts than those with diets dominated by benthic algae and other plants. The data indicated that C. banarescui showed broad flexibility in their feeding habits. Feeding heavily on plant materials might lead to the development of longer digestive tracts, increasing the active surface area for digestion; alternatively, there may be less invested in development of the digestive tract when feeding primarily on carnivorous diets where the respective digestive enzymes are readily available. The data suggest that phenotypic plasticity in the digestive tract length of C. banarescui is associated more with the abundant protein‐rich carnivorous food sources in the studied habitats. Whether this digestive tract plasticity has a genetic background remains to be verified in future studies.  相似文献   
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