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981.
982.
Jeroen A. van Kan Ce Zhang Piravi Perumal Malar Johan R. C. van der Maarel 《Biomicrofluidics》2012,6(3)
An easy method is introduced allowing fast polydimethylsiloxane (PDMS) replication of nanofluidic lab-on-chip devices using accurately fabricated molds featuring cross-sections down to 60 nm. A high quality master is obtained through proton beam writing and UV lithography. This master can be used more than 200 times to replicate nanofluidic devices capable of handling single DNA molecules. This method allows to fabricate nanofluidic devices through simple PDMS casting. The extensions of YOYO-1 stained bacteriophage T4 and λ−DNA inside these nanochannels have been investigated using fluorescence microscopy and follow the scaling prediction of a large, locally coiled polymer chain confined in nanochannels. 相似文献
983.
In this study we investigated if the occurrence of the sticking region was a result of diminishing potentiation (coinciding delayed muscle activation) or the result of a mechanically poor region in which the muscles can produce less force. A regular one-repetition maximum (1RM) free-weight bench press was compared with isometric bench presses performed at 12 different positions. A lower force at the sticking region compared to the other regions in the isometric bench presses would confirm the mechanically-poor-position hypothesis. Twelve resistance-trained males (age 21.7 ± 1.3 years, mass 78 ± 5.8 kg, height 1.81 ± 0.05 m) were tested in 1RM and in isometric contractions in bench press in 12 different positions, indicated by the vertical distance between barbell and sternum, covering the whole range of motion during the concentric phase. Barbell kinematics and muscle activity were registered. In both types of executions a region of lower force output was observed, which supports the mechanically-poor-position hypothesis. Electromyographic activity of four muscles showed the same pattern in the isometric and 1RM attempts. It was concluded that diminishing effect potentiation could not explain the existence of the sticking region. 相似文献
984.
This paper addresses the challenge of striking a balance between, on one hand, mitigating uncertainty through the existence of systematic processes and structures and, on the other, stimulating creativity through allowable variation in work processes and structures. Both objectives are fundamental aspects of product development work. Our main finding is that both objectives can be achieved simultaneously. We introduce trust as a mediating variable. We show first, that being systematic in the processes for obtaining information and applying explicit organizational rules and structures in product development work creates an atmosphere of trust in the organization. Second, we show that trust increases creativity. The paper contributes to an understanding of how and why trust is important in product development organizations and of how trust can be actively managed. Above all, the paper contributes to the understanding of how uncertainty and creativity should be managed in organizations conducting product development. 相似文献
985.
Kavita Shalia Sudha Savant Vijaya A. Haldankar Tulip Nandu Poonam Pawar Siddhi Divekar V. K. Shah Purvi Bhatt 《Indian journal of clinical biochemistry : IJCB》2012,27(1):74-82
To analyse the association of high sensitivity C-reactive (hsCRP) protein levels and −717A/G single nucleotide polymorphism
of CRP with acute myocardial infarction (AMI) in the Indian population. Study population included 100 MI cases wherein 32
patients had experienced previous MI (MI-Group-1), 68 MI cases were recruited at presentation (MI-Group-2) and equal number
of age and gender matched healthy individuals. hsCRP levels were determined by ELISA and genotyping of −717A/G was carried
out by polymerase chain reaction-based restriction digestion method. The −717A/G genotypes did not influence hsCRP level and
their distribution did not differ between groups. However, in the present study hsCRP demonstrated significant correlation
with BMI in controls of both the genders and with triglycerides in females of AMI at presentation who otherwise are with low
risk profile. Identifying traditional risk factors associated with inflammation may help in controlling the acute event. 相似文献
986.
Meera S. Ghadge Purva P. Naik Bijaynath P. Tiwari Ruprekha M. Hegde Tanaji J. Matale 《Indian journal of clinical biochemistry : IJCB》2012,27(1):97-99
Breast cancer is one of the most frequent malignancies in the world. Available staging procedures to detect breast cancer
are bone scan, chest X-ray, liver ultrasonography, computerized tomography, estimation of tumor markers like carbohydrate
antigen (CA15-3) and carcino embryonic antigen. These procedures are expensive and may not be required in all cases. Out of
70 patients studied, 55 had normal CA15-3 and 15 had elevated levels of Ca15-3. Eight (14.5%) of the 55 patients with normal
CA15-3 had abnormal bone scan. Fifteen patients had CA15-3 levels above the normal range and among these 9 (60%) had abnormal
bone scan. While prime facie it would appear that a high level of CA15-3 correlate with abnormal bone scan, it is also true
that the numbers are small at present and conclusions about the validity of CA15-3 as marker of bone metastasis may be premature. 相似文献
987.
Schmitt KU Wider D Michel FI Brügger O Gerber H Denoth J 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(1):57-72
Wrist injuries are frequently observed after falls in snowboarding. In this study, laboratory experiments mimicking forward and backward falls were analysed. In six different falling scenarios, participants self-initiated falls from a static initial position. Eighteen volunteers conducted a total of 741 trials. Measurements were taken for basic parameters describing the kinematics as well as the biomechanical loading during impact, such as impact force, impact acceleration, and velocity. The effective mass affecting the wrist in a fall also was determined. The elbow angle at impact showed a more extended arm in backward falls compared to forward falls, whereas the wrist angle at impact remained similar in forward and backward falls. The study results suggest a new performance standard for wrist guards, indicating the following parameters to characterize an impact: an effective mass acting on one wrist of 3-5 kg, an impact angle of 75 degrees of the forearm relative to the ground, and an impact velocity of 3 m/s. 相似文献
988.
Yong Huo 《Journal of Zhejiang University. Science. B》2010,11(8):631-633
##正##Dr.Gruntzig et al.(1979) successfully completed the world's first percutaneous coronary intervention (PCI),a percutaneous transluminal coronary 相似文献
989.
Ling Xia Ying-lan Gong Xiu-wei Zhu Yu Zhang Qi Sun Heng-gui Zhang 《Journal of Zhejiang University. Science. B》2010,11(6):402-416
The aim of this study is to build two mathematical models of canine ionic currents specific to right atria and left atria.The canine left atria mathematical model was firstly modified from the Ramirez-Nattel-Courtemanche(RNC) model using the recently available experimental data of ionic currents and was further developed based on our own experimental data.A model of right atria was then built by considering the differences between right atria and left atria.The two developed models well reproduced the exper... 相似文献
990.
Qing-jun Liu Wei-wei Ye Hui Yu Ning Hu Li-ping Du Ping Wang 《Journal of Zhejiang University. Science. B》2010,11(5):323-331
Neurochip based on light-addressable potentiometric sensor(LAPS),whose sensing elements are excitable cells,can monitor electrophysiological properties of cultured neuron networks with cellular signals well analyzed.Here we report a kind of neurochip with rat pheochromocytoma(PC12) cells hybrid with LAPS and a method of de-noising signals based on wavelet transform.Cells were cultured on LAPS for several days to form networks,and we then used LAPS system to detect the extracellular potentials with signals d... 相似文献