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121.
Objective: Thiol-disulphide homeostasis (TDH) has a critical role in various clinical disorders. We aimed to assess the association of TDH with acute tonsillopharyngitis (AT) in children.

Methods: This study included 94 (73 viral and 21 bacterial) tonsillopharyngitis patients and 88 control children. Their native thiol, total thiol, and disulphide levels were measured.

Results: Viral and bacterial tonsillopharyngitis patients had lower native thiol levels compared with healthy children (P?P?=?0.008, respectively). Both groups had lower total thiol levels compared with control children (P?=?0.002 for viral, P?=?0.011 for bacterial). The disulphide levels were lower in bacterial than in viral tonsillopharyngitis patients (P?=?0.04), and there was a significant difference between viral tonsillopharyngitis patients and the control group (P?P?P?=?0.017 for bacterial). The disulphide/native thiol and disulphide/total thiol ratios were significantly higher in viral (P?P?=?0.017 for both) than in healthy children. In all patients, a correlation was found between the levels of C-reactive protein (CRP) and native thiol (r?=??0.211, P?=?0.04), CRP and total thiol (r?=??0.217, P?=?0.036), white blood cell (WBC) and native thiol (r?=??0.228, P?=?0.002), WBC and total thiol (r?=??0.191, P?=?0.01), and WBC and disulphide (r?=?0.160, P?=?0.03).

Discussion: TDH is altered in AT in children. The alteration is more prominent in viral than in bacterial tonsillopharyngitis.  相似文献   
122.
G.O. Afacan  T. Onal  G. Akansel  A.S. Arslan 《HOMO》2017,68(5):393-397
The lateral angle of the internal acoustic canal is one of the measurements of petrous bone that has been previously studied for sex estimation, mostly in adults. We aimed at evaluating the effects of age, side, and sex on the lateral angle of the internal acoustic canal in pediatric patients.Pediatric routine cranial MRI studies were retrospectively investigated for this study. The lateral angle was measured on T2-weighted axial images when the anterior and posterior lips of the meatus and the cochlea were clearly visible on the same image. The data were evaluated for age, side and sex-related changes. Although 552 temporal bones from 273 patients were inspected, due to exclusion criteria lateral angle could be satisfactorily measured only in 101 temporal bones from 58 patients. The measurements did not differ significantly between sexes. An age-related, statistically significant decrease was observed for the entire pediatric sample studied, as well as for the males, but not for females. The measurements did not differ from side to side.The significant age-related decrease in lateral angle in male pediatric patients that was not detected in female counterparts may be the reflection of a sex-related difference in temporal bone development during childhood. Routine cranial MRI data may help investigators study age and sex-related changes in lateral angle in children.  相似文献   
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Biological Trace Element Research - The quantity of some essential and non-essential elements of wild edible mushroom samples collected from Tunceli Province of Turkey was determined by using flame...  相似文献   
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To study the effects of continuous positive airway pressure (CPAP) on lung volume, and upper airway and respiratory muscle activity, we quantitated the CPAP-induced changes in diaphragmatic and genioglossal electromyograms, esophageal and transdiaphragmatic pressures (Pes and Pdi), and functional residual capacity (FRC) in six normal awake subjects in the supine position. CPAP resulted in increased FRC, increased peak and rate of rise of diaphragmatic activity (EMGdi and EMGdi/TI), decreased peak genioglossal activity (EMGge), decreased inspiratory time and inspiratory duty cycle (P less than 0.001 for all comparisons). Inspiratory changes in Pes and Pdi, as well as Pes/EMGdi and Pdi/EMGdi also decreased (P less than 0.001 for all comparisons), but mean inspiratory airflow for a given Pes increased (P less than 0.001) on CPAP. The increase in mean inspiratory airflow for a given Pes despite the decrease in upper airway muscle activity suggests that CPAP mechanically splints the upper airway. The changes in EMGge and EMGdi after CPAP application most likely reflect the effects of CPAP and the associated changes in respiratory system mechanics on the afferent input from receptors distributed throughout the intact respiratory system.  相似文献   
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To study respiratory timing mechanisms in patients with occlusive apnea, inspiratory and expiratory times (TI and TE) were calculated from the diaphragmatic electromyogram obtained in seven patients during non-rapid-eye-movement (NREM) sleep. Peak diaphragmatic activity (EMGdi) had a curvilinear relationship with TI during the ventilatory and occlusive phases such that TI shortened as EMGdi decreased during the ventilatory phase (r = 0.87, P less than 0.05) and it prolonged as EMGdi increased during the occlusive phase (r = 0.89, P less than 0.02). However, EMGdi vs. TI for the occlusive phase was shifted to the right of that for the ventilatory phase, reflecting the relatively longer TI during upper airway occlusion. TI also had a linear relationship with pleural pressure (r = 0.94, P less than 0.001) that remained unchanged during the ventilatory and occlusive phases such that it prolonged as negative inspiratory pressure increased. These results indicate that respiratory timing is continuously modified in patients with occlusive apnea as inspiratory neural drive fluctuates during NREM sleep and suggest that this modification is due to the net effects of changing inspiratory neural drive and afferent input predominantly from upper airway mechanoreceptors.  相似文献   
128.
In this paper, radiation shielding parameters such as mass attenuation coefficients and half value layer (HVL) of some antioxidants are investigated using MCNPX (version 2.4.0). The validation of the generated MCNPX simulation geometry for antioxidant structures is provided by comparing the results with standard WinXcom data for radiation mass attenuation coefficients of antioxidants. Very good agreement between W?NXCOM and MCNPX was obtained. The results from the validated geometry were used to calculate the shielding parameters of different antioxidants. The radiation attenuation properties of each antioxidant were compared with each other. The results showed that, on average, the highest and the lowest radiation mass attenuation coefficients were observed on hesperidin and delphinidin chloride, respectively. It can be concluded that Monte Carlo simulation is a strong tool and an alternate method where experimental investigations are not possible and a standard simulation setup can be used in further studies for different biological structures. It can also be concluded that the obtained results from this study are very useful for radiology and radiotherapy applications where antioxidants are frequently used.  相似文献   
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Abstract

Using problems from real life contexts which is related to learners environment or their culture plays an important role in their learning that concept. In this regard, science educators especially physics educators search for real-life domain of theoretical concepts for effective science teaching and they consider analogical and physical models as an opportunity in their instruction. In the presented activity, we worked with 66 senior pre-service science teachers from our science teaching methods course. We used crowd movements as a real-life domain of our analogical models to scientifically explain a stampede case, then utilized physical model to explore continuity equation. Real life problem based scenarios could be used while taking advantage of the 3?D modeling in teaching of scientific principle. As a result, we found that pre-service teachers were able to make scientific explanation for causes of stampedes by using modeling activity. High school teachers and upper-level instructors could benefit from including the modeling activity introduced in this study to help their students understand the concepts related to continuity equation by designing a physical model based on an analogical model. Via the physical model, students are able to make predictions, observations, interpretations and explanations of a complex and abstract scientific phenomenon.  相似文献   
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