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81.
82.
In this study, plasma and red blood cell (RBC) antioxidant status and plasma lipid peroxidation were investigated in 46 hemodialysis patients. In addition, the effect of erythropoietin (EPO) and EPO-vitamin E combination therapy on plasma and RBC antioxidant status, and plasma lipid peroxidation were examined.

There were 10 healthy subjects in the control group and 10 hemodialysis patients in the untreated group. The third group included 36 hemodialysis patients that were given EPO (100 U/kg) for 3 months, 3 times per week. The fourth group included 36 hemodialysis-patients from the EPO group that were given EPO at a 50% decreased dose + vitamin E (300 mg/day) for 3 months.

MDA levels in the untreated group, the EPO group and the EPO + vitamin E groups were found to be higher than the control group (p<0.001, in both). Furthermore, MDA levels in both of the treatment groups were lower when compared to the untreated group (p<0.001, in both). Plasma vitamin E levels in the untreated, the EPO group and EPO + vitamin E groups were lower than the control group (p<0.001). In contrast, plasma vitamin E levels in the treatment groups were higher in comparison with the control group (p<0.05). SOD activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p<0.001). SOD activities in the treatment groups were higher than the control group (p<0.001). The SOD activities in the EPO + vitamin E group increased when compared to the EPO group (p<0.001). CAT activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p<0.001 in untreated and EPO groups, p<0.01 in EPO + vitamin E group). CAT activities in EPO and EPO + vitamin E groups were increased when compared to the untreated group (p<0.01).

In conclusion, our findings have shown that antioxidant status decreased and lipid peroxidation increased in hemodialysis patients. EPO has an antioxidant effect on the RBC and plasma antioxidant status, and plasma lipid peroxidation. These effects were moderately increased by the combination of vitamin E and EPO.  相似文献   
83.
Between April 2001 and April 2002 were studied 106 women with a clinical diagnosis of vaginal candidiasis seen at the Gynecology and Obstetrics Ambulatory of the Hospital das Clínicas da Universidade Federal de Goiás. The patients were assessed on two occasions, before starting treatment with itraconazole or fluconazole (initial visit) and 14 days after treatment (return). At two visits the signs and symptoms were recorded and vaginal secretion was collected. According to the clinical evaluation, itraconazole was effective in 64.3%, while fluconazole was effective in 71.0% of the patients. The mycological cure rates (negative culture) in the return were 64.3% for the patients treated with itraconazole and 78.9% for the patients treated with fluconazole. The MICs of itraconazole and fluconazole for 80 Candida isolates were determined by Etest method. We investigated the correlation between in vitro susceptibility (Susceptible, Susceptibility Depending Dose and Resistant) to itraconazole and fluconazole with clinical outcome of the patients. The success rates were 63.9% for itraconazole and 90.6% for fluconazole in the susceptible category, 100.0% for both drugs in the susceptible dose dependent category, and 0.0% for both drugs in the resistant category. Our results showed there were a positive correlation between in vitro susceptibility test results with clinical outcome in vaginal Candida infections and that both drugs might be one choice in the treatment of vaginal candidiasis.  相似文献   
84.
In the present work, spectroscopic, kinetic and dosimetric features of the radicalic intermediates produced after gamma irradiation at room temperature of solid triclosan (2,4,4-trichloro-2-hydroxydiphenyl ether; TCS) were investigated by means of electron spin resonance spectroscopy (ESR) at various temperatures. The same material was also irradiated with UV light, and an ESR spectrum very similar to that obtained for gamma-irradiated TCS, was recorded. The ESR spectrum of TCS is characterized by an unresolved doublet with resonance lines split into other doublets. An evaluation technique based on variations of four assigned peak-to-peak amplitudes and signal intensity was adopted, to monitor the evolution of the spectrum under different experimental conditions. Radicals of one type were proposed to be created upon irradiation exhibiting decays via intra-track and inter-track recombination reactions with activation energies of 43 ± 2 and 139 ± 6 kJ/mol, respectively. A radical exhibiting axial g anisotropy and interacting with two un-equivalent protons was found to describe the experimental spectrum well. The sensitivity of TCS to gamma radiation was high (G = 0.12) suggesting TCS to be a suitable dosimetric material in measuring normal and accidental radiation doses in the range of (1–25 kGy).  相似文献   
85.
86.
We investigated the histological structure and histochemistry of the nasal conchae of geese and compared these structures with those of other avian species. The rostral, middle and caudal conchae were dissected from the nasal cavity of eight geese, fixed in Carnoy’s solution and embedded in paraffin. The entrance of the rostral concha was lined by keratinized stratified squamous epithelium, which toward the middle concha was replaced by modified keratinized squamous epithelium, the deep layer of which opened into tubular glandular structures containing secretory epithelium on crypt-like invaginations. The lamina propria of the rostral concha contained numerous Grandry’s and Herbst corpuscles, which are pressure-sensitive receptors peculiar to waterfowl. The lamina propria of the middle concha contained solitary lymphoid follicles and lymphocyte infiltrations. The cartilaginous component of the middle concha was highly convoluted and resembled a spiral of two and a half scrolls, which were lined by pseudostratified columnar epithelium. We observed that unlike mammals, this epithelium contained mostly intraepithelial alveolar glands rather than goblet cells. The caudal concha was similar to the middle concha, but less convoluted. It was lined by olfactory epithelium and its lamina propria contained serous Bowman’s glands as well as olfactory nerve fibers. Histochemical examination demonstrated that while none of the conchae contained sulfated mucins, except for the cartilage, the intraepithelial glands of the rostral and middle conchae contained mostly carboxylated acidic mucin and some neutral mucin, and were thus of the mixed type. The outermost scroll of the spiral of the middle concha contained some periodate-Schiff stained mucins. Of the glands of the mucosa of the middle concha, the deep tubuloalveolar glands in the convex parts of the scrolls contained primarily acidic mucins, while the shallow intraepithelial alveolar glands in the concave parts of the scrolls contained primarily neutral mucins. Our findings indicate that the rostral and caudal conchae primarily have a sensory function and the middle concha participates in mucosal defense.  相似文献   
87.
Polyphenol oxidase (PPO) of nettle (Urtica dioica L.) was extracted and purified through (NH4)2SO4 precipitation, dialysis, and CM-Sephadex ion-exchange chromatography and was used for its characterization. The PPO showed activity to catechol, 4-methylcatechol, L-3,4-dihydroxyphenylalanine (L-DOPA), L-tyrosine, p-cresol, pyrogallol, catechin and trans-cinnamic acid. For each of these eight substrates, optimum conditions such as pH and temperature were determined and L-tyrosine was found to be one of the most suitable substrates. Optimum pH and temperature were found at pH 4.5 and 30°C respectively and Km and Vmax values were 7.90?×?10?4?M, and 11290?EU/mL for with L-tyrosine as substrate. The inhibitory effect of several inhibitors, L-cysteine chloride, sodium azide, sodium cyanide, benzoic acid, salicylic acid, L-ascorbic acid, glutathione, thiourea, sodium diethyl dithiocarbamate, β-mercaptoethanol and sodium metabisulfite were tested. The most effective was found to be sodium diethyl dithiocarbamate which acted as a competitive inhibitor with a Ki value of 1.79?×?10?9?M. In addition one isoenzyme of PPO was detected by native polacrylamide slab gel electrophoresis.  相似文献   
88.
The in vitro and in vivo inhibitory effects of 5-(3α, 12α-dihydroxy-5-β-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (1), 5-(3α, 7α, 12α-trihydroxy-5-β-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (2), 5-(3α, 7α, 12α-triacetoxy-5-β-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (3) and acetazolamide on rainbow trout (Oncorhynchus mykiss) (RT) erythrocyte carbonic anhydrase (CA) were investigated. The RT erythrocyte CA was obtained by affinity chromatography with a yield of 20.9%, a specific activity of 422.5?EU/mg protein and a purification of 222.4-fold. The purity of the enzyme was confirmed by SDS-PAGE. Inhibitory effects of the sulfonamides and acetazolamide on the RT erythrocyte CA were determined using the CO2-Hydratase method in vitro and in vivo studies. From in vitro studies, it was found that all the compounds inhibited CA. The obtained I50 value for the sulfonamides (1), (2) and (3) and acetazolamide were 0.83, 0.049, 0.82 and 0.052?μM, respectively. From in vivo studies, it was observed that CA was inhibited by the sulfonamides (1), (2) and (3) and acetazolamide.  相似文献   
89.
In this study, di(2,6-dimethylphenol) (Di-DMP), di(2,6-diisopropylphenol) (Di-DIP, dipropofol) and di(2,6-di-t-butylphenol) (Di-DTP) were synthesized by the reaction of monomeric phenol derivatives with catalytic CuCl(OH). TMEDA and Na2S2O4. Their antioxidant capacity and radical scavenging activity were examined using different in vitro methodologies such as 1,1-diphenyl-2-picryl-hydrazyl (DPPH·) free radical scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity by ferric thiocyanate, total reducing power by potassium ferricyanide reduction method, superoxide anion radical scavenging, hydrogen peroxide scavenging and ferrous ions chelating activities.  相似文献   
90.
Some novel benzimidazole derivatives were synthesized and their in vitro effects on rat liver microsomal NADPH-dependent lipid peroxidation (LP) level, ethoxyresorufin O-deethylase (EROD) and antifungal activities were determined. A significant decrease in male rat liver microsomal LP level was noted by compounds 4c (52%), 4e (58%) and 4h (43%) at 10? 3 M concentration. Compounds 4c (100.0%), 4h (100.0%), 5c (98.0%) and 5h (100.0%) inhibited the microsomal ethoxyresorufin O-deethylase (EROD) enzyme activity better than that of the specific inhibitor caffeine (85%). Among these compounds, only compounds 4b and 4h exhibited moderate activity against C.albicans whereas the others had weak effects.  相似文献   
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