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1.
Abstract

The Westland petrel (Procellaria westlandica) is an endemic New Zealand species and one of the very few burrowing seabird species still breeding on mainland New Zealand. It nests only on a series of coastal ridgelines near to Punakaiki on the West Coast of the South Island. Between 2002 and 2005, surveys were undertaken at 28 of the 29 known colonies. The area occupied by the colonies was 73 ha; most colonies had fewer than 50 burrows, but six colonies had 201–500 burrows and four colonies had more than 1000 burrows. We find that the current breeding range of Westland petrel and the location of individual colonies are similar to those reported in both the 1950s and 1970s. Based on total burrow counts at 28 colonies and burrow occupancy rates determined by annual monitoring, the annual breeding population is estimated to be between 2954 and 5137 breeding pairs.  相似文献   
2.
The bioactive compounds content and the antioxidant activity (AA) of twelve fruits native to the Cerrado were compared with the Red Delicious apple by means of the antiradical efficiency (using the 2,2-diphenyl-1-picrylhydrazil assay/DPPH), ferric reducing antioxidant power (FRAP) and the β-carotene/linoleic system. The antiradical efficiency (AE) and the kinetic parameters (Efficient concentration/EC50 and time needed to reach the steady state to EC50 concentration/TEC50) of the DPPH curve were also evaluated for comparison with the Trolox equivalent (TE) values. A strong, significant and positive correlation was observed between the TE and AE values, whereas a weak and negative correlation was observed between TE and EC50, suggesting that the values of AE and TE are more useful for the determination of antiradical activity in fruits than the widely used EC50. The total phenolic content found in the fruits corresponded positively to their antioxidant activity. The high content of bioactive compounds (flavanols, anthocyanins or vitamin C) relative to the apple values found in araticum, cagaita, cajuzinho, jurubeba, lobeira, magaba and tucum corresponded to the high antioxidant activity of these fruits. Flavanols and anthocyanins may be the main bioactive components in these Cerrado fruits. The daily consumption of at least seven of the twelve Cerrado fruits studied, particularly, araticum, cagaita, lobeira and tucum, may confer protection against oxidative stress, and thus, they may prevent chronic diseases and premature aging. The findings of this study should stimulate demand, consumption and cultivation of Cerrado fruits and result in sustainable development of the region where this biome dominates.  相似文献   
3.
4.
Antioxidant activity of leaf extracts from Bauhinia monandra   总被引:2,自引:0,他引:2  
Bauhinia monandra Kurz. is used in Brazil for the treatment of diabetes. Since this activity may be correlated with the presence of antioxidant compounds, leaf extracts of B. monandra were evaluated for their radical scavenging capacity (RSC). An ethanolic extract was taken up in aqueous methanol and partitioned with hexane, chloroform, ethyl acetate to yield three organic extracts together with remaining aqueous extract. The RSC was determined spectrophotometrically using 1,1-diphenylpicrylhydrazyl free radical (DPPH). The chloroform and ethyl acetate extracts were the most appropriate as sources of antioxidant compounds as shown by their inhibition concentration (IC50) and inhibition percentage (IP) values. The antioxidant activity of such extracts was attributed to the presence of three compounds of different polarities (flavonoids and steroids). The chloroform and ethyl acetate extracts exhibited an IC50 of approximately 2 mg/g DPPH and IP values in the range of 60-65%. The results indicate that the extracts of B. monandra have a very potent antioxidant activity, compared with the pure catechins used as positive controls and with other plant extracts.  相似文献   
5.

Background

Patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) commonly require hospitalization and admission to intensive care unit (ICU). It is useful to identify patients at the time of admission who are likely to have poor outcome. This study was carried out to define the predictors of mortality in patients with acute exacerbation of COPD and to device a scoring system using the baseline physiological variables for prognosticating these patients.

Methods

Eighty-two patients with acute respiratory failure secondary to COPD admitted to medical ICU over a one-year period were included. Clinical and demographic profile at the time of admission to ICU including APACHE II score and Glasgow coma scale were recorded at the time of admission to ICU. In addition, acid base disorders, renal functions, liver functions and serum albumin, were recorded at the time of presentation. Primary outcome measure was hospital mortality.

Results

Invasive ventilation was required in 69 patients (84.1%). Fifty-two patients survived to hospital discharge (63.4%). APACHE II score at the time of admission to ICU {odds ratio (95 % CI): 1.32 (1.138–1.532); p < 0.001} and serum albumin (done within 24 hours of admission) {odds ratio (95 % CI): 0.114 (0.03-0.432); p = 0.001}. An equation, constructed using the adjusted odds ratio for the two parameters, had an area under the ROC curve of 91.3%. For the choice of cut-off, sensitivity, specificity, positive and negative predictive value for predicting outcome was 90%, 86.5%, 79.4% and 93.7%.

Conclusion

APACHE II score at admission and SA levels with in 24 hrs after admission are independent predictors of mortality for patients with COPD admitted to ICU. The equation derived from these two parameters is useful for predicting outcome of these patients.  相似文献   
6.
Five dihydro-piran-2,4-diones, including 5,6-dimethyl-dihydro-piran-2,4-dione one of the intermediates of the synthesis of caloverticilic acid, were synthesized and submitted to molluscicidal bioassay. The compound's yields varied from moderate to good (42%- 80%) and were achieved through the preparation of the dianion of ethyl acetoacetate, reaction with and aldehyde followed by hydrolysis of the ester (NaOH, H(2)O, 2 h, T.A.) and lactonization in acidic medium (HCl, 0 degrees C). The 5,6-dimethyl-dihydro-piran-2,4-dione and three analogous dihydro-piran-2,4-diones 6-substituted,-phenyl, (4-methoxy-phenyl), and -propenyl, showed significant activities against the Biomphalaria glabrata egg masses, while the analogous 6-(3,4-dimethoxy-phenyl) was inactive as molluscicide. This activity is reported for the first time, extending the range of biological activities of this group.  相似文献   
7.
The isolation of ent-kaur-16-en-19-oic acid (1) from the leaves and bark of Annona glabra and its determination by reversed-phase HPLC with a photodiode array detector is described. The results indicate that 1 accumulates in the bark of the plant with only very low concentrations in the leaves. Levels of 1 varied throughout the year being highest for bark and leaves in the autumn (5.29 +/- 0.23 and 0.27 +/- 0.01 mg/g dry weight, respectively) and lowest in the spring for bark and in the winter for leaves (4.00 +/- 0.25 and 0.11 +/- 0.01 mg/g dry weight, respectively).  相似文献   
8.
The aetiology of anti-neutrophil cytoplasmic antibody (ANCA)-associated systemic vasculitis has not been well defined. Here we review two factors which may play a role in the pathogenesis of the disease: genetics and infection. In particular, we discuss the role of autoantibodies to LAMP-2, which may arise following infection with Gram-negative bacteria, and may contribute to the development of ANCA-associated systemic vasculitis in genetically susceptible individuals.  相似文献   
9.
The Annona fruit borer, Cerconota anonella, causes significant damage to the fruits of Annona squamosa (custard apple) and A. muricata (soursop). The methods currently available for the control of this pest are costly and new techniques, possibly involving the use of pheromones for trapping or disrupting the mating cycle of the insect are required. In order to provide the basic information required for the development of new control systems, the reproductive behaviour of the moth was observed under laboratory conditions. The calling and courtship behaviours exhibited by virgin females and males of C. anonella commenced at the eighth hour of the scotophase and continued for a 3.5‐h period. Males were attracted by conspecific females as young as 1 d old, and showed a courtship behaviour composed of three steps: antennation, wing fanning and short flights. Mating mainly occurred when both males and females were between 2 and 5 d old, but maximum activity was observed on the third day after emergence. Receptive females elevated their wings, showing their abdomens where the abdominal hairpencils were already exposed. As part of the courtship repertoire and immediately prior to copula, males performed pronounced sideways movements of their abdomens, a behaviour that appears to be exclusive to C. anonella.  相似文献   
10.
OBJECTIVE: To evaluate cell proliferation in clinically healthy oral mucosa exposed to smoking and alcohol carcinogens over a period of 24 months using the AgNOR staining technique. STUDY DESIGN: Sixty patients were initially evaluated: 17 were control individuals, 25 were smokers and 18 were smokers and alcohol drinkers. Fifty-two of these patients were reevaluated. Specimens for cytology were obtained from swabs of lower lip mucosa, border of the tongue and floor of the mouth and underwent AgNOR staining for evaluation of mean number and mean area of AgNOR dots per nucleus and percentage of nuclei with > 3 and > 5 AgNOR dots. Student t and Kruskal-Wallis tests were used to compare values obtained. RESULTS: A statistically significant increase was found in mean number of AgNOR dots per nucleus in 2 groups. One group showed a tendency toward increase of these values. The results of the longitudinal evaluation (Kruskal-Wallis test) revealed a statistically significant difference in number and area of AgNOR dots in the cells of the lower lip. CONCLUSION: The increase of the variables suggests that the longitudinal evaluation of changes in cell proliferation in individuals exposed to smoking and alcohol carcinogens may be a useful monitoring tool.  相似文献   
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