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1.

Objectives

To evaluate the ovicidal and oviposition deterrent activities of five medicinal plant extracts namely Aegle marmelos (Linn.), Limonia acidissima (Linn.), Sphaeranthus indicus (Linn.), Sphaeranthus amaranthoides (burm.f), and Chromolaena odorata (Linn.) against Culex quinquefasciatus and Aedes aegypti mosquitoes. Three solvents, namely hexane, ethyl acetate, and methanol, were used for the preparation of extracts from each plant.

Methods

Four different concentrations—62.5 parts per million (ppm), 125 ppm, 250 ppm, and 500 ppm—were prepared using acetone and tested for ovicidal and oviposition deterrent activities. One-way analysis of variance (ANOVA) was used to determine the significance of the treatments and means were separated by Tukey''s test of comparison.

Results

Among the different extracts of the five plants screened, the hexane extract of L. acidissima recorded the highest ovicidal activity of 79.2% and 60% at 500 ppm concentration against the eggs of Cx. quinquefasciatus and Ae. aegypti, respectively. Similarly, the same hexane extract of L. acidissima showed 100% oviposition deterrent activity at all the tested concentrations against Cx. quinquefasciatus and Ae. aegypti adult females.

Conclusion

It is concluded that the hexane extract of L. acidissima could be used in an integrated mosquito management program.  相似文献   
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The mosquitocidal activity of different fractions and isolated compounds from the ethyl acetate extract of Ecbolium viride root was assessed on larvae and pupae of Culex quinquefasciatus Say (Diptera: Culicidae). The larvae and pupae were exposed to concentrations of 6.125, 12.5, 25 and 50 ppm for fractions and 1, 2.5, 5 and 10 ppm for compound. Among the 12 fractions screened, fraction 6 from the ethyl acetate extract of E. viride was recorded to have the highest larvicidal and pupicidal activities against C. quinquefasciatus. The lethal concentration (LC50 and LC90) values of fraction 6 were 4.26 and 9.0 ppm against C. quinquefasciatus larvae and 6.55 and 12.19 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Fraction 7 was recorded to have moderate activity with LC50 and LC90 values of 11.25 and 25.02 ppm against C. quinquefasciatus larvae and 13.33 and 31.15 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Ecbolin A and ecbolin B were identified from fractions 7 and 6, respectively. The structure of the isolated compounds was identified on the basis of spectral data (1H NMR and 13C NMR) and compared with literature spectral data. Further, the isolated compound, ecbolin B, from fraction 6 was recorded to have strong larvicidal and pupicidal activities than ecbolin A. The LC50 and LC90 values of ecbolin B on C. quinquefasciatus larvae were 1.36 and 2.76 ppm, and on pupae, these were 1.54 and 3.51 ppm, respectively. The present results suggest that ecbolin B could be used as a mosquitocidal agent against C. quinquefasciatus.  相似文献   
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BackgroundThe consequences of atherosclerosis can be detected by multislice computed tomography (MSCT), invasive coronary angiogram (CAG) and the resultant myocardial ischaemia by myocardial perfusion single photon emission computed tomography (MPS). In this study an attempt is made to compare MSCT with MPS and also to compare the MSCT findings with that of invasive CAG in patients suspected to have coronary artery disease (CAD).Materials and methodsA total of 99 patients suspected to have CAD underwent both MSCT and MPS with 99mTc sestamibi. The MSCT studies were classified as having no CAD, significant CAD (>50% diameter stenosis), and insignificant CAD (<50% diameter stenosis). Myocardial perfusion single photon emission computed tomography was reported as normal and reversible ischaemia. In a subgroup of 33 patient invasive CAG was done.ResultsIn 99 patients, 396 coronaries were evaluated with MSCT and MPS. Coronary artery calcium scoring (CACS) in these patient ranged from 0 to 2200. No CAD was noted in 128 (32%) coronaries but MPS was found abnormal in 9 (7%) coronaries. Insignificant CAD was noted in 169 (43%) coronaries amongst which reversible ischaemia was noted in 23 (14%). Significant CAD was noted in 99 (25%) coronaries of which only 54 (55%) were MPS positive for reversible ischaemia. The MSCT has a negative predictive value (NPV) of 97%. When MSCT was normal, MPS was almost normal, but the reverse was not true. That is when MPS was normal MSCT was not always normal but showed lesion of insignificant obstruction.In the subset of 33 patients, who underwent invasive angiogram, 132 coronaries were evaluated. Coronary angiogram showed 48 coronaries (36%) to have significant CAD (>50% diameter stenosis). Multislice computed tomography correlated well in 46 (84%) with P value of <0.001 (χ2-test) but for 9 (16%) showing overestimation due to increased CACS (>800). Myocardial perfusion single photon emission computed tomography was normal in 15 (27%) coronaries.ConclusionMyocardial perfusion single photon emission computed tomography provides functional information of the anatomical lesions and MSCT provides anatomical information. Both are two different diagnostic modalities. The MSCT has high NPV in patients with less likelihood for CAD. When compared with CAG, the correlation with MSCT was good and is useful where the calcium score is low.  相似文献   
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Herein, we reported the supramolecular organization of N-acyltris(hydroxymethyl)aminomethane (NATM) in the solid state as well as in aqueous solution. Single crystal X-ray diffraction revealed that NATM adopts a fully interdigitized structure. The thermodynamic parameters associated with thermotropic phase behaviour of NATM was determined by differential scanning calorimetry. The molecular packing and phase state of the NATM analyzed by laurdan and prodan fluorescence supports the formation of an interdigitized phase in aqueous solution. The potential application of the self-assembled NATM vesicles was demonstrated through entrapping model drug, Rhodamine B.

Self assembly of N-acyltris(hydroxymethyl)aminomethane into interdigitized vesicles.  相似文献   
6.
Background Previous studies demonstrated higher mortality for patients with a longer pre-intensive care unit (ICU) hospital length of stay (LOS), in well-resourced settings. Objectives The study aimed to determine the association between pre-ICU hospital LOS and ICU outcomes in a resource-limited setting. We hypothesised that longer pre-ICU hospital LOS would be associated with higher ICU mortality. Methods This was a retrospective cohort study measuring the association between pre-ICU hospital LOS and ICU outcomes using data extracted from a regional hospital ICU in KwaZulu-Natal, South Africa. Consecutive ICU admissions of all patients (medical and surgical) older than 18 years were included during the study period September 2014 to August 2018. A corrected sample size of 2 040 patients was identified. Multivariable logistic regression was used to assess the primary outcome of ICU mortality, and multivariable Cox proportional hazard regression was used for the secondary outcome of ICU LOS. Results The median pre-ICU hospital LOS was 1 day (interquartile range (IQR) 0 - 2 days). The median length of ICU stay was 2.4 days (IQR 1.1 - 4.8 days) and the observed ICU mortality was 16% (n=327/2 040). Pre-ICU hospital LOS was not associated with ICU mortality in the unadjusted (odds ratio (OR) 1.00; 95% confidence interval (CI) 0.98 - 1.02; p=0.68; n=2 040) and fully adjusted logistic regression models (OR 1.00; 95% CI 0.98 - 1.03; p=0.90; n=1 981) using a complete case analysis for missing patient-level covariates. In Cox proportional hazard models, there was no association between pre-ICU hospital LOS and ICU LOS (hazard ratio 1.00; 95% CI 0.98 - 1.03; p=0.72; n=1 967), including when stratified by admission source. Conclusion Pre-ICU hospital LOS was not associated with either ICU mortality or ICU LOS in a resource-limited setting. Future studies should aim to include multicentre data and evaluate long-term outcomes. Contributions of the study The study was conducted in a resource-limited setting and found no association between prolonged LOS pre-ICU and patient outcomes. Several potential explanations for this observation have been explored. This important subject is pertinent to the appropriate use of limited resources and encourages future studies to evaluate this association and to consider longer-term outcomes (e.g. 30-day mortality) in future findings.  相似文献   
7.
Asbestos‐related lung cancer accounts for 4–12% of all lung cancers worldwide. Since putative mechanisms of carcinogenesis differ between asbestos and tobacco induced lung cancers, tumors induced by the two agents may be genetically distinct. To identify gene expression biomarkers associated with asbestos‐related lung tumorigenicity we performed gene expression array analysis on tumors of 36 patients with primary lung adenocarcinoma, comparing 12 patients with lung asbestos body counts above levels associated with urban dwelling (ARLC‐AC: asbestos‐related lung cancer‐adenocarcinoma) with 24 patients with no asbestos bodies (NARLC‐AC: non‐asbestos related lung cancer‐adenocarcinoma). Genes differentially expressed between ARLC‐AC and NARLC‐AC were identified on fold change and P value, and then prioritized using gene ontology. Candidates included ZNRF3, ADAM28, PPP1CA, IRF6, RAB3D, and PRDX1. Expression of these six genes was technically and biologically replicated by qRT‐PCR in the training set and biologically validated in three independent test sets. ADAM28, encoding a disintegrin and metalloproteinase domain protein that interacts with integrins, was consistently upregulated in ARLC across all four datasets. Further studies are being designed to investigate the possible role of this gene in asbestos lung tumorigenicity, its potential utility as a marker of asbestos related lung cancer for purposes of causal attribution, and its potential as a treatment target for lung cancers arising in asbestos exposed persons. © 2010 Wiley‐Liss, Inc.  相似文献   
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Rheumatoid arthritis is a chronic, progressive and systemic inflammatory disorder mainly affecting the synovial joints. In the present study, we evaluated the anti-arthritic effect of the methanol extract of Saraca asoca (Roxb.) Wilde., (Fabaceae) on adjuvant induced arthritis by assessing paw swelling, body weight, the levels of lysosomal enzymes, protein bound carbohydrates, serum cytokines, urinary collagen and histopathology of joints. It was found that S. asoca methanol extract at doses of 50, 100 and 200 mg/kg reduced the paw thickness and elevated the mean body weight of arthritic rats. The treatment of S. asoca showed a significant reduction in the levels of both plasma and liver lysosomal enzymes. The protein bound carbohydrates and urinary collagen contents were also decreased at a significant level by the treatment of S. asoca methanol extract. The histopathological study of the joints showed the anti-arthritic property of S. asoca which nearly normalized the histological architecture of the joints. Further, we established the anti-arthritic activity of S. asoca methanol extract by measuring the levels of cytokines in both arthritic and treated rats. The treatment of S. asoca reduced the levels of pro-inflammatory cytokines. In conclusion, S. asoca methanol extract was capable of ameliorating the conditions of arthritis in adjuvant induced arthritic rats.  相似文献   
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