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21.
Notation analysis has now gained wide use in the assessment of competitive football play. Computer-aided methods have largely replaced the use of hand-notation systems. Whilst a hand-notation approach has been adopted previously in assessing injury-risk in football, the recording and analysing of events with injury potential are time-consuming. In this report, a computerised system of notating incidents in the game is described. Key incidents are monitored with respect to degree of injury potential, location and other factors. The use of the system is illustrated by comparing home and away performances in Premier League matches between Manchester United and Liverpool F.C. The system has advantages in speed and accuracy of handling data related to injury and injury risk.  相似文献   
22.
Two strains of 64 endophytic bacteria, Bacillus cereus Si-Ps1 and Pseudomonas azotoformans La-Pot3-3, isolated from Citrus sinensis and C. sinensis var. Thomson's leaves, respectively, reduced N-acyl homoserine-based quorum sensing in bioindicator strain Pseudomonas syringae pv. syringae (Pss) B728a and the biofilm production and swarming motility of field isolate Pss 3289. A homolog of aiiA gene encoding an AHL-lactonase was found in B. cereus (Si-Ps1), suggesting that this isolate can degrade the quorum-sensing signal molecules of Pss 3289. The crude extract of endophytic bacterium, B. cereus (Si-Ps1), inhibited Pss 3289 biofilm formation after 48 and 96 h by 55% and 58%, respectively. Similar reductions in biofilm formation were conferred by crude extracts of P. azotoformans (La-Pot3-3). Correspondingly, the number of planktonic cells in cultures treated with these extracts was higher than in control cultures, indicating a direct effect on biofilm formation and not on cell growth. In greenhouse assays, the virulence of Pss 3289 to different citrus cultivars was decreased when coinoculated with these endophytic bacteria.  相似文献   
23.
The minimal running velocity at which maximal oxygen uptake (VO2max) is elicited during an incremental test to exhaustion has been used to prescribe training for competitive middle- and long-distance runners. The purpose of this study was to determine the relationship between velocity at lactate turnpoint (vLTP) and vVO2max in long-distance runners. For this purpose 11 highly trained endurance runners were selected randomly from the national team. The average age, height and mass of the subjects were 24.36±1.1 years, 1.73±0.02 m and 63.25±21 kg respectively. The first test was used to determine vVO2max and VO2max (a continuous run to exhaustion with the start velocity at 10 km/h and the velocity increased 1 km/h per minute). The second test was used to determine vLTP (start velocity was 10 km/h and velocity increased 1 km/h for 4 min to reach lactate concentration over 5 mmol/l). The average VO2max and vVO2max of subjects were 58.54±2.8 ml/kg/min and 19±0.29 km/h respectively. Pearson’s correlation coefficient and SPSS 12 software were used for analysing data. There was a positive moderate correlation between vLTP and vVO2max (p=0.037, r=0.63). This study may indicate that, the more the athlete is capable of delaying the accumulation of his/her lactate, and the higher the velocity at which the accumulation takes place, the higher vVO2max he/she can have. On the other hand, coaches can design training programmes at vVO2max intensity to promote a higher vLTP.  相似文献   
24.
PurposeThe aim of the current study was to investigate the prevalence of shoulder pain and to explore the possible associated risk factors in middle-aged women.MethodsA total of 500 middle-aged women, aged 45–65 years, participated in this cross-sectional study. The point and lifetime prevalence of shoulder pain were calculated. Linear and logistic regressions were used to determine the possible associations between the risk factors and present shoulder pain.ResultsThe point and lifetime prevalence of shoulder pain were 18.6% and 27.6%, respectively. The logistic regression analysis demonstrated a significant association between present shoulder pain and history of shoulder pain and trauma, osteoporosis, trapezius muscle pain, and cervical radiculopathy (p < 0.05). However, there was no significant association between present shoulder pain and diabetes mellitus or postural deviation (p > 0.05).ConclusionThe results indicated that shoulder pain has considerable prevalence in middle-aged women. In addition, a history of shoulder pain and trauma, osteoporosis, trapezius muscle pain, and cervical radiculopathy were found to be associated with present shoulder pain. Future research should concentrate on longitudinal designs that explore preventive strategies and risk factors for shoulder pain.  相似文献   
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26.
Objective To find the clinical signs that are the best predictors of hypoxemia (SpO2=92%) in acute asthma in children. Methods Color of skin, dyspnea (by single breath counting), alertness, respiratory rate, presence of audible wheeze, wheezing on auscultation, accessory muscle use, nasal flaring, pulse rate, systolic and diastolic blood pressure, pulsus paradoxus and oxygen saturation at room air (by pulse oximetry) were recorded at the time of presentation and one hour after presentation after completion of 3 doses of nebulized salbutamol and budesonide. Results Hypoxemia (SpO2≤92%) was seen in 45% children at presentation and 14(28.6%) after one hour. The clinical signs that correlated significantly with hypoxemia at both time points were dyspnea assessed by single breath count (OR 3.3, 95% Cl 0.9–12.9), accessory muscle use score ≥3 (OR 3.0, 95% Cl 0.9–15.4) and pulsus paradoxus >10 (OR 3.0, 95% Cl 0.7–13.6). In a multiple logistic regression model accessory muscle score >-3 and pulsus paradoxus >10 were identified as independent predictors of hypoxemia (sensitivity 64.3%, specificity 91%). Conclusion Physical assessment in a child with acute exacerbation of asthma should at least include accessory muscle use and pulsus paradoxus, since these predict hypoxemia the best.  相似文献   
27.
Kynurenic acid (KYNA) is an endogenous antagonist of alpha7 nicotinic receptors and all ionotropic glutamate receptors. Its neuroprotective activity has been suggested. In this study, the presence of KYNAin human saliva and its potential bactericidal role was investigated. KYNAwas found in all samples of human saliva with mean concentration of 3.4 nM. The concentration of KYNA in saliva obtained from patients with odontogenic abscesses was 3.5 times higher than in healthy subjects. We have shown that the human gingival fibroblasts produce KYNAand an inflammatory stimulant, lipopolysaccharide, enhanced its synthesis in vitro. The bactericidal effect of KYNA was also presented. We hypothesize that KYNA may contribute to the control of oral microflora.  相似文献   
28.
The aim of this study was to evaluate the activity of alkaline (ALP) and acid (ACP) phosphatase in the blood serum of rats after ovariectomy and with estrogen replacement therapy. The relationship between mandible and spine bone mineral density (BMD) and parameters of bone remodeling was also estimated. The concentration of serum total alkaline and acid phosphatase was higher in the rats with estrogen deficiency, and statistically lower in rats administering 17 beta-estradiol. ALP and ACP levels were correlated significantly negative with mandible and spine BMD. Carried out examinations confirmed increasing bone resorption during experimental postmenopausal osteoporosis.  相似文献   
29.
Herein, a novel aptamer-functionalized magnetic adsorbent was developed and combined with magnetic solid-phase extraction (MSPE) for the specific enrichment of Pb2+ ions prior to flame atomic absorption spectrometric detection. First, silver-coated magnetite core–shell nanoparticles (Fe3O4@Ag MNPs) were synthesized by the chemical reduction of silver ions on the surface of magnetite nanoparticles. After that, the selective DNA aptamer against Pb2+ was conjugated on the surface of the synthesized nanoparticles to form aptamer-modified magnetic nanoparticles (Fe3O4@Ag-APT). The characterization of the prepared adsorbent was performed through SEM imaging, XRD, FT-IR, EDX, and DRS instruments. The influence of the various experimental parameters on the adsorption and desorption steps in MSPE was investigated via Taguchi experimental design to optimize different parameters. Under the optimized conditions, the Pb2+ calibration graph was linear in the range of 33–1000 μg L−1. The relative standard deviation (RSD%) of the method for six replicates containing 100 μg L−1 of Pb2+ ions was 0.34%. Furthermore, the limit of detection (LOD) and the limit of quantification (LOQ) were 10 μg L−1 and 33.3 μg L−1, respectively. Finally, the applicability of the proposed method was successfully confirmed by preconcentration and determination of trace amounts of Pb2+ ions in tap and seawater samples. We showed a proof of concept for Fe3O4@Ag-APT as an efficient bio-adsorbent, offering a promising strategy for the specific binding/removal of toxic heavy metal ions.

Herein, a novel aptamer-functionalized magnetic adsorbent was developed and combined with magnetic solid-phase extraction (MSPE) for the specific enrichment of Pb2+ ions prior to flame atomic absorption spectrometric detection.  相似文献   
30.
OBJECTIVE: With recent advances in molecular genetics, mouse models have been generated for a number of disease states. Recently, the authors and others have begun to examine normal age-related cognitive decline using mice as a model system. In this article, and the companion article that follows, the authors present data intended to better parameterize the aging phenotype in mice and examine the possible underlying neuronal mechanisms with special emphasis on age-related changes in calcium homeostasis. METHODS: Young (4-6-month-old) and aged (22-24-month-old) C57BL/6 mice were analyzed in terms of their spatial learning abilities in the hidden platform version of the Morris water maze and the delay win-shift version of the Olton radial arm maze. RESULTS: Although aged mice exhibited cognitive impairments in both behavioral tasks used, the extent of impairment differed between the two tasks, which might prove to be advantageous under certain experimental settings. CONCLUSIONS: Like in other areas of biomedical research, mice have become an invaluable research tool in the investigation of learning and memory. It is expected that similar benefits can be realized by developing mouse models for age-related cognitive decline.  相似文献   
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