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We aimed to investigate the cytotoxic effects of nimbolide, a limonoid present in leaves and flowers of the neem tree (Azadirachta indica) on human breast cancer cells. The molecular mechanisms involved in the apoptotic activity exerted by nimbolide were studied on the estrogen dependent (MCF-7) and estrogen independent (MDA-MB-231) human breast cancer cell lines. The growth inhibitory effect of nimbolide was assessed by MTT assay. Apoptosis induction by nimbolide treatment was determined by JC-1 mitochondrial membrane potential staining, cytochrome c release, caspase activation, cleavage of PARP and AO/EtBr dual staining. The modulation of apoptotic proteins (intrinsic pathway: Bax, bad, Bcl-2, Bcl-xL, Mcl-1, XIAP-1 and caspase-3, 9; extrinsic pathway: TRAIL, FasL, FADDR and Caspase-8) were studied by western blot and real time PCR analysis. Treatment with nimbolide resulted in dose and time-dependent inhibition of growth of MCF-7 and MDA-MB-231 cells. The occurrence of apoptosis in these cells was indicated by JC-1 staining, modulation of both intrinsic and extrinsic apoptotic signaling molecules expression and further apoptosis was confirmed by AO/EtBr dual staining. These events were associated with: increased levels of proapoptotic proteins Bax, Bad, Fas-L, TRAIL, FADDR, cytochrome c and reduced levels of the anti-apoptotic proteins Bcl-2, Bcl-xL, Mcl-1 and XIAP-1. Nimbolide induces the cleavage of pro-caspase-8, pro-caspase-3 and PARP. The above data suggest that nimbolide induces apoptosis by both the intrinsic and extrinsic pathways. With evidence of above data it is suggested that nimbolide exhibit anticancer effect through its apoptosis-inducing property. Thus, nimbolide raises new hope for its use in anticancer therapy.  相似文献   
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Mosquito-borne diseases have an economic impact, including loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. In mosquito control programs, botanical origin may have the potential to be used successfully as eggs, larvae, and adult. The larvicidal, ovicidal, and repellent activities of crude benzene and ethyl acetate extracts of leaf of Ervatamia coronaria and Caesalpinia pulcherrima were assayed for their toxicity against three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus (Diptera: Culicidae). The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in benzene extract of E. coronaria against the larvae of Anopheles Stephensi, Aedes aegypti, and Culex quinquefasciatus with the LC50 and LC90 values were 79.08, 89.59, and 96.15 ppm and 150.47, 166.04, and 174.10 ppm, respectively. Mean percent hatchability of the ovicidal activity was observed 48 h posttreatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. The leaf extract of E. coronaria was found to be most effective than Caesalpinia pulcherrima against eggs/egg rafts of three vector mosquitoes. For E. coronaria, the benzene extract exerted 300, 250, and 200 ppm against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus, respectively. The results of the repellent activity of benzene and ethyl acetate extract of E. coronaria and Caesalpinia pulcherrima plants at three different concentrations of 1.0, 2.5, and 5.0 mg/cm2 were applied on skin of fore arm in man and exposed against adult female mosquitoes. In this observation, these two plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal ecofriendly approach for the control of mosquitoes. This is the first report on the mosquito larvicidal, ovicidal, and repellent activities of the reported E. coronaria and Caesalpinia pulcherrima plants.  相似文献   
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ObjectiveTo investigate the bioactive constituents of Shemamruthaa (SM), a herbal combination and its therapeutic effects on the mitochondrial functions with reference to lipid peroxidation (LPO), antioxidant status, citric acid cycle enzymes and electron transport chain enzymes in mammary tissues of 7,12-dimethylbenz(a)-anthracene (DMBA) induced mammary carcinoma in rat model.MethodsAdult female Sprague-Dawley rats were used for the study and were divided into four groups. Group I served as control and Group II rats were induced mammary carcinoma by administration of DMBA (25 mg/kg b.w.) orally. The normal and cancer-induced rats (Group III) were treated with SM (400 mg/kg b.w./day) orally by gastric incubation for 14 days. Group IV rats served as SM-treated control animals.ResultsCancer-induced rats showed a considerably increased level of LPO with concomitant decreased levels of antioxidants, citric acid cycle enzymes, electron transport chain enzymes and cytochrome contents in the mammary tissue. Treatment with SM brought back the aforementioned biochemical parameters to near normal.ConclusionsFrom the results, it can be inferred that Shemamruthaa possesses significant anticancer effect through its role in attenuation of LPO, prevention of membrane damage and restoring membrane integrity.  相似文献   
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Objective

To evaluate the effect of aqueous seed extract of Solanum surattense (S. surattense) on the oxidative potential of cauda epididymal spermatozoa.

Methods

S. surattense seed extract was orally administered at the dosage of 10 mg/kg b.w. for 15 days, after which aspartate transferase (AST), alanine transferase (ALT), glutamate dehydrogenase (GDH), citric acid and iso-citrate dehydrogenase (ICDH) were assayed.

Results

The activity levels of the enzymes AST and ALT, which are considered to be the androgenicity in the sperm suspension, were depleted in the extract fed rats. The activity level of the enzyme ICDH, was reduced significantly in the treated group (P<0.001).

Conclusions

It can be concluded that the oral administration of the aqueous seed extract of S. surattense can deplete the oxidative stress of cauda epididymal spermatozoa in albino rats.  相似文献   
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In the present study, the multiple targets have been identified in the mediation of anti-inflammatory response of curcumin. The anti-inflammatory pathway of curcumin was identified through docking with of curcumin with various inflammation inducing enzymes like glycogen synthase kinase (GSK-3β), p38 mitogen activated protein kinase (MAPK), COX, interleukin-1β converting enzyme (ICE) and tumor necrosis factor-α converting enzyme (TACE). Theoretical docking study was used for the prediction of the conformation orientation and position (pose) of the bioactive compound into the binding pocket and estimation of effective target-ligand interactions (scoring) was utilized for conformational sampling. The final docked conformations were selected according to their scores. The binding target GSK-3β (-6.44) was found to be more selective for curcumin binding when compared with MAPK (-4.08), COX (-7.35), ICE (-4.02), TACE (-6.38) and their respective native ligand. The binding takes place through hydrogen bonding interactions of curcumin with the amino acids in the substrate enzyme. The key amino acids involved were Vall35, Gln185 and Lys85 in GSK-3β. The binding efficiency of curcumin was compared with a standard molecule GF109203 which showed a docking score of - 4.97. These findings enabled us to identify the keto form of curcumin as a best choice of lead compound to target GSK-3β.  相似文献   
7.
Procalcitonin appears to be an early and sensitive marker of bacterial infection in a variety of clinical settings. The use of levels of procalcitonin to predict infection in children undergoing cardiac surgery, however, may be complicated by the systemic inflammatory response that normally accompanies cardiopulmonary bypass. The aim of our study was to estimate peri-operative concentrations of procalcitonin in non-infected children undergoing cardiac surgery. Samples of serum for assay of procalcitonin were obtained in 53 patients at baseline, 24, 48, and 72 hours following cardiac surgery. Concentrations were assessed using an immunoluminetric technique. Median concentrations were lowest at baseline at less than 0.5 nanograms per millilitre, increased at 24 hours to 1.8 nanograms per millilitre, maximized at 48 hours at 2.1 nanograms per millilitre, and decreased at 72 hours to 1.3 nanograms per millilitre, but did not return to baseline levels. Ratios of concentrations between 24, 48 and 72 hours after surgery as compared to baseline were 6.15, with 95 percent confidence intervals between 4.60 and 8.23, 6.49, with 95 percent confidence intervals from 4.55 to 9.27, and 4.26, with 95 percent confidence intervals between 2.78 and 6.51, respectively, with a p value less than 0.001. In 8 patients, who had no evidence of infection, concentrations during the period from 24 to 72 hours were well above the median for the group. We conclude that concentrations of procalcitonin in the serum increase significantly in children following cardiac surgery, with a peak at 48 hours, and do not return to baseline within 72 hours of surgery. A proportion of patients, in the absence of infection, had exaggerated elevations post-operatively.  相似文献   
8.
Earthworms have been widely used in traditional medicine for thousands of years. However, it is only during the past few decades, with the development of biochemical technologies, that research on the pharmaceutical effects has been initiated. The present study was carried out to investigate the hepatoprotective and antioxidant properties of indigenous earthworm powder (Perionyx excavatus), using alcohol induction as a model of hepatotoxic and oxidative damage. Alcohol-hepatotoxic rats exhibited elevation in the lipid-peroxidative marker thiobarbituric acid reactive substance (TBARS). A decrease in the activities of enzymatic antioxidant enzymes: Superoxide dismutase (SOD), Catalase (CAT), Glutathione peroxidase (GPx), and non-enzymatic antioxidant vitamin C, vitamin E and reduced glutathione (GSH) was observed. Oral administration of dried earthworm powder (500 mg/kg body weight) for 42 days reversed these parameters towards normalcy. These results suggest that the indigenous earthworm Perionyx excavatus could afford a significant hepatoprotective and antioxidant effect against alcohol induced rats.  相似文献   
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