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911.
Rats confronted with the onset of a light gradient display a transient increase in locomotion called theactivity response (AR) and a dark preference (Godsil & Fanselow, 2004). These experiments demonstrate that the magnitude of the AR can be blunted
with Pavlovian fear-conditioning procedures via associative and nonassociative fear. Although manifested in decreased locomotion,
the blunted AR effect was not due to increased freezing or immobility behaviors. Instead, rats displayed reduced rearing and
an increase in a class of behaviors calledstationary activity. These results suggest that the lighting differential supplied by the cue influences the topography of defensive behavior
and reduces the expression of freezing. This procedure provides a means by which to examine learned and unlearned defensive
responses to the same stimulus. 相似文献
912.
Cuhadar S Atay A Koseoglu M Dirican A Hur A 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(2):202-214
Introduction
The collected and shipped blood samples are exposed to a various extra-analytical factors prior to analysis. The aim of the study was to determine the stability of analytes in serum gel tubes and plain tubes exposed to a range of storage temperatures and times after centrifugation.Materials and methods:
Fifteen healthy volunteers were recruited and venous blood was collected into four tubes, two with and two without gel separator. Analyzing the baseline samples in 30 min, all were stored at 4ºC or 24ºC for 6, 12, 18, 24, 30, 36, 48 and 72 hours and 1 week. Sixteen biochemical anaytes were measured on each sample. Variations remained under the desirable bias considered as clinically insignificant.Results:
On day three, most analytes remained stable including albumin, protein, creatinine, cholesterol, triglycerides, gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LD) regardless of tube types. Glucose concentration decreased markedly (P = 0.001) beginning from the first hours of storage in plain serum. The stability maximized for the analytes including glucose, total bilirubin, urea nitrogen (BUN), uric acid stored at 4 ºC in gel tubes. Aspartate aminotransferase (AST) activity increased significantly (P = 0.002) up to 48-h, however bias was not significant clinically. High density lipoprotein (HDL) concentration was stable in gel tubes at 24 ºC, in plain tubes at 4 ºC stored up to 36-h.Conclusion:
Serum gel or non-gel tubes might be used interchangeably for 11 analytes chilled or at 24 ºC, whereas some restrictions must be applied for glucose, AST, BUN, HDL, and uric acid. 相似文献913.
A microfluidic device that is able to perform dielectric spectroscopy is developed. The device consists of a measurement chamber that is 250 μm thick and 750 μm in radius. Around 1000 cells fit inside the chamber assuming average quantities for cell radius and volume fraction. This number is about 1000 folds lower than the capacity of conventional fixtures. A T-cell leukemia cell line Jurkat is tested using the microfluidic device. Measurements of deionized water and salt solutions are utilized to determine parasitic effects and geometric capacitance of the device. Physical models, including Maxwell-Wagner mixture and double shell models, are used to derive quantities for sub-cellular units. Clausius-Mossotti factor of Jurkat cells is extracted from the impedance spectrum. Effects of cellular heterogeneity are discussed and parameterized. Jurkat cells are also tested with a time domain reflectometry system for verification of the microfluidic device. Results indicate good agreement of values obtained with both techniques. The device can be used as a unique cell diagnostic tool to yield information on sub-cellular units. 相似文献
914.
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
915.
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
916.
力学教学对当代大学生的创新能力和素质的培养有着重要的作用.该文结合教学实践和体会,通过力学史的渗透、多种教学手段相结合、“一题多解”的训练、使用力学知识解决生活实际问题和鼓励学生参加课程实践活动等方式,不断激发学生学习兴趣,提高思维积极性,培养创新精神,加强创新能力和科学素质. 相似文献
917.
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
918.
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
919.
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
920.
Su Ye Sohn Gi Young Jang Byung Min Choi 《Journal of Zhejiang University. Science. B》2010,11(7):539-541
Congenital atresia of the left main coronary artery is a rare occurrence, and surgical revascularizationbypass graft is required.
We here report a rare case of congenital coronary anomaly in an infant. A 10-month-old male infant was admitted to the hospital
with heart failure symptoms. Echocardiographic examinations revealed mitral valve regurgitation and ischemic changes of the
anterolateral papillary muscle and chordae. Coronary angiography showed atresia of the left main coronary artery with a severe
hypoplastic left anterior descending artery and a circumflex coronary artery. Unfortunately, sudden cardiac arrest occurred
after catheterization and the infant did not recover despite of immediate cardiopulmonary resuscitation. Further studies are
needed to find a newer diagnostic method to detect coronary anomaly in an infant, and coronary angiography, if necessary,
has to be performed very carefully. 相似文献