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1.
We present design, characterization, and testing of an inexpensive, sheath-flow based microfluidic device for three-dimensional (3D) hydrodynamic focusing of cells in imaging flow cytometry. In contrast to other 3D sheathing devices, our device hydrodynamically focuses the cells in a single-file near the bottom wall of the microchannel that allows imaging cells with high magnification and low working distance objectives, without the need for small device dimensions. The relatively large dimensions of the microchannels enable easy fabrication using less-precise fabrication techniques, and the simplicity of the device design avoids the need for tedious alignment of various layers. We have characterized the performance of the device with 3D numerical simulations and validated these simulations with experiments of hydrodynamic focusing of a fluorescently dyed sample fluid. The simulations show that the width and the height of the 3D focused sample stream can be controlled independently by varying the heights of main and side channels of the device, and the flow rates of sample and sheath fluids. Based on simulations, we also provide useful guidelines for choosing the device dimensions and flow rates for focusing cells of a particular size. Thereafter, we demonstrate the applicability of our device for imaging a large number of RBCs using brightfield microscopy. We also discuss the choice of the region of interest and camera frame rate so as to image each cell individually in our device. The design of our microfluidic device makes it equally applicable for imaging cells of different sizes using various other imaging techniques such as phase-contrast and fluorescence microscopy.  相似文献   
2.
Given the paucity of studies conducted to know the effect of suddenness and earlier onset of endocrinological changes associated with hysterectomy, on the serum and urinary levels of calcium, magnesium and phosphate the present study was conducted to compare the levels of calcium, magnesium and phosphate in serum and urine of hysterectomised and natural menopausal south Indian women. This is a cross-sectional observational study. The study included three groups of 30 healthy premenopausal, 30 early surgical menopausal and 30 natural post menopausal women. Women suffering from any endocrine disease were excluded. Analysis was performed in serum and urine sample. The levels of calcium, magnesium and phosphate in serum and calcium/creatinine, magnesium/creatinine and phosphate/creatinine ratio were estimated in urine by spectrophotometric method. Hysterectomised women (serum calcium: 8.7 ± 0.09 mg/dl; urine calcium/creatinine: 0.16 ± 0.02) have significantly low serum calcium (p < 0.001) and high urinary calcium/creatinine (p = 0.002) ratio and post menopausal women (serum magnesium: 2.1 ± 0.03; serum phosphate: 4.4 ± 0.16; urinary calcium/creatinine: 0.17 ± 0.02; urinary magnesium/creatinine: 0.09 ± 0.01) have significantly high serum magnesium (p = 0.016), serum phosphate (p = 0.043) and high urinary calcium/creatinine (p = 0.002), magnesium/creatinine ratio (p = 0.025) compared to healthy pre menopausal women. Post menopausal women (serum calcium: 9.1 ± 0.08) have significantly high serum calcium and phosphate compared to hysterectomised women (serum phosphate: 3.93 ± 0.11). Hysterectomised women have significantly low serum calcium, oestrogen and high urinary calcium/creatinine ratio compared to healthy premenopausal women and low serum calcium and low serum phosphate compared to natural postmenopausal women. Natural postmenopausal women had low serum oestrogen and high serum magnesium, serum phosphate, urinary calcium creatinine ratio and urinary magnesium creatinine ratio compared to healthy premenopausal women.  相似文献   
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4.
The cultural construction of home and school knowledge in tribal India   总被引:1,自引:0,他引:1  
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5.
Dependence on alcohol, nicotine and duration of alcohol consumption are known to alter thyroid function tests. This study was conducted to assess the effect of interaction between the duration of alcohol consumption and alcohol dependence on TFT. The subjects consisted of 38 male patients with alcohol dependent syndrome co morbid with nicotine dependent syndrome, 33 male patients with alcohol dependent syndrome and 30 male normal healthy volunteers. Liver function tests, haematological parameters and thyroid function tests were assayed. Two way multivariate ANOVA was used to assess the interaction effect by SPSS 21 package. Multivariate analysis of combined TFT levels revealed no significant (P = .078) difference amongst groups based on alcohol dependence, significant difference (P = .001) amongst groups based on duration of alcohol consumption and no significant (P = .604) interaction effect between duration of alcohol consumption and alcohol dependence. Tests of between subject effects for individual TFT revealed significant (P = .014) difference in T3 between groups based on alcohol dependence, significant difference in the levels of fT4 (P = .001), T3 (P = .07) and T4 (P < .001) between groups based on duration of alcohol consumption was observed. Interaction between the effect of duration of alcohol consumption and alcohol dependence for individual TFT did not reveal any significance. fT4, TSH and T4 levels were significantly low in persons consuming alcohol for more than 20 years. TSH levels were significantly low in ADS compared to controls. Significant decrease in the levels of thyroid hormones was observed as the duration of alcohol consumption increased.  相似文献   
6.
Pushpa Khare 《Resonance》2014,19(5):406-420
The only source of information about the universe is the radiation that we receive from various astronomical sources. This article describes some of the methods used by astronomers to analyze this radiation to unveil the mysteries of the universe.  相似文献   
7.
Background:Developing appropriate concussion prevention and management paradigms in middle school(MS)settings requires understanding parents’general levels of concussion-related knowledge and attitudes.This study examined factors associated with concussion-symptom knowledge and care-seeking attitudes among parents of MS children(aged 10-15 years).Methods:A panel of 1224 randomly selected U.S.residents,aged ≥18 years and identifying as parents of MS children,completed an online questionnaire capturing parental and child characteristics.The parents’concussion-symptom knowledge was measured using 25 questions,with possible answers being“yes”,“maybe”,and“no”.Correct answers earned 2 points,“maybe”answers earned 1 point,and incorrect answers earned 0 point(range:0-50;higher scores=better knowledge).Concussion care-seeking attitudes were also collected using five 7-point scale items(range:5-35;higher scores=more positive attitudes).Multivariable ordinal logistic regression models identified predictors of higher scores.Models met proportional odds assumptions.Adjusted odds ratios(aORs)with 95%confidence intervals(95%CIs)(excluding 1.00)were deemed statistically significant.Results:Median scores were 39(interquartile range:32-44)for symptom knowledge and 32(interquartile range:28-35)for care-seeking attitude.In multivariable models,odds of better symptom knowledge were higher in women vs.men(aOR=2.28;95%CI:1.71-3.05),white/non-Hispanics vs.other racial or ethnic groups(aOR=1.88;95%CI:1.42-2.49),higher parental age(10-year-increase aOR=1.47;95%CI:1.26-1.71),and greater competitiveness(10%-scale-increase aOR=1.24;95%CI:1.13-1.36).Odds of more positive care-seeking attitudes were higher in white/non-Hispanics vs.other racial or ethnic groups(aOR=1.45;95%CI:1.06-1.99)and in older parental age(10-year-increase aOR=1.24;95%CI:1.05-1.47).Conclusion:Characteristics of middle school children’s parents(e.g.,sex,race or ethnicity,age)are associated with their concussion-symptom knowledge and care-seeking attitudes.Parents’variations in concussion knowledge and attitudes warrant tailored concussion education and prevention.  相似文献   
8.
Starting in the 1990s, the Caribbean two-island nation of Trinidad and Tobago witnessed the establishment of several Indian-music format radio stations, most of which now stream their content on the World Wide Web or otherwise make their content available beyond the range of their terrestrial radio transmitters. The convergence of traditional terrestrial radio with audio streaming technology combined with the spread of high speed broadband connections has expanded the audience of a typical radio station from a few kilometers to a globally dispersed set of listeners who often include those physically displaced from their native cultural programming. The present investigation examines the Facebook comments of domestic and foreign listeners to Indian-music format radio stations from the Republic of Trinidad and Tobago.  相似文献   
9.
There is a rich body of research devoted to the causes and remedies of social loafing in workplace teams. However, the social loafing phenomenon remains underinvestigated from the perspective of students in undergraduate business classroom teams. In particular, how they define and respond to loafing remains unknown. This article reports findings from a two-stage study that shows social loafing as a more complex construct than current conceptions suggest. Moreover, students avoid confronting loafers and prefer to have instructors administer postpriori justice based on their self-report of individual contributions. Based on the findings and recent writings, the article speculates on the causes of these student responses to social loafing in classroom teams.  相似文献   
10.
Avinash Khare 《Resonance》2013,18(10):885-896
In this article I shall present a brief review of the hundred-year young Bohr model of the atom. In particular, I will first introduce the Thomson and the Rutherford models of atoms, their shortcomings and then discuss in some detail the development of the atomic model by Niels Bohr. Further, I will mention its refinements at the hand of Sommerfeld and also its shortcomings. Finally, I will discuss the implication of this model in the development of quantum mechanics.  相似文献   
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