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111.
Low density lipoprotein (LDL) was isolated from normal rabbits and was modified with acetic anhydride. Blood monocyte derived
macrophages from normal and hypercholesterolemic (HC) rabbits were cultured, and on the 8th day the cells were incubated with
native and modified LDL to study their binding and degradation. Macrophages from both normal and hypercholesterolemic rabbits
express a limited number of receptors for normal plasma LDL whereas they exhibit a large number of receptors for acetyl LDL.
There was no significant difference between binding and degradation of acetyl LDL by normal or hypercholesterolemic cells.
However, binding and degradation of native LDL by monocytes of hypercholesterolemic cells were significantly less (p<0.0001)
in comparison to binding and degradation of native LDL by normal cells indicating that there is a feedback inhibitory pathway
in the cell that inhibits the synthesis of LDL receptors in the presence of excess LDL. 相似文献
112.
Emokpae M. A. Das S. C. Orok T. Mohammed A. Z. Hassan S. A. 《Indian journal of clinical biochemistry : IJCB》2004,19(1):62-66
This study was conducted to investigate the diagnostic performance characteristics of prostate specific antigen (PSA) by comparing
serum PSA value with histological findings in patients suspevted of having prostate cancer in Aminu Kano Teaching Hospital.
Nigeria. Clinical and Laboratory records were examined and collated for serum PSA values, together with histological findings
of biopsy specimen, clinical diagnosis, age of patients, and mode of presentation. The serum PSA values were determined by
ELECSYS 1010 autoanalysers Roche, Germany based on electrochemiluminescence immunoassay technique. The results show that serum
PSA values increase with age in the assymptomatic non-cancer patients who came for medical check up but were within normal
limit. In prostatic disease conditions PSA values were raised in benign prostatic hyperplasia 35.957± 4.0315ng/ml, in undifferentiated
carcinoma 56.22±4.295ng/ml and adenocarcinoma >100ng/ml as compared to the normal range (0–4ng/ml). These cases were confirmed
by histological diagnosis. It is concluded that PSA evaluations is a sensitive marker for prostate cancer but because of various
other conditions that affect serum PSA concentration, other methods of investigations such as Digital Rectal examination,
Trans Urethral Ultra-Sonography and histological examination should be combined to confirm diagnosis. Prognosis of patients
will be better if early diagnosis is made. 相似文献
113.
Simple and sensitive Liquid Chromatography-Tandem Mass Spectrometry (LCMS/MS)
method was developed and validated, then was implicated on hypertensive human
subjects to study drug interaction of atorvastatin (ATVS) and Olmesartan (OLM) on
status of Angiotensin-II (ANG-II). The ANG-II in plasma was extracted with 5 mL
methanol containing 5 % formic acid through C18 (cartridges)
liquid–liquid extraction, dried and reconstituted with 1 mL of 16 % acetonitrile in
0.1 % formic acid in water. The chromatographic separation of ANG-II with a Agilent
technology 6410 Triple quadrupole was carried multiple reaction monitoring scan mode
with a Agilent 1290 Infinity LC system for UHPLC. The sample were separated on a
(Thermo Scientific) Hy-Purity advance (50 × 4.6 mm, 5 μm) using Mobile Phase A: 16 %
acetonitrile in 0.1 % formic acid in water and Mobile Phase B: 0.1 % formic acid in
methanol at a flow rate of 0.3 mL/min, performed at ambient temperature. The mobile
phase gradient of 16 % acetonitrile in water was linearly increased to 38 %
acetonitrile over 10 min and subsequently the mobile-phase was increased to 100 %
acetonitrile over 15 min. The developed method was validated for specificity,
accuracy, precision, stability, linearity, sensitivity and recovery. The method was
linear between peak area ratio of standard and internal standard over the range of
50–800 ng/mL. The method was successfully applied for the drug interaction study
revealed levels of ANG-II were significantly higher in ATVS + OLM treatment
condition as compared to individual treatment of OLM. This reflects the reason of
low effectiveness of ATVS + OLM in combination instead of synergistic
activity.
Electronic supplementary material
The online version of this article (doi:10.1007/s12291-014-0457-x) contains supplementary material, which is available to authorized users. 相似文献114.
Mascha Verma Rashmi Khadapkar Priyadarshi Soumyaranjan Sahu Bibhu Ranjan Das 《Indian journal of clinical biochemistry : IJCB》2006,21(2):90-94
An increase in the communication within the healthcare services, both nationally and internationally, has strengthened the
need for harmonization of measurements and reference intervals in laboratory medicine. In the present report, the calculated
reference interval for serum creatinine (sCr) levels of healthy normal individuals (n=1121) in different sex and age groups
are compared with the established interval. The calculated reference interval for sCr level was 0.4–1.3 mg/dL and 0.6 to 1.3
mg/dL in the age groups of 21–40 and 41–60 years respectively. The difference between the mean sCr values in total males and
total females (age range 21–60 years) was statistically significant (p<0.0001); When male and female subjects were analyzed
age-group wise, the data showed a significant difference in mean sCr values (p<0.0001) in three age groups (21–30, 31–40 and
41–50 years) however, in older age group (51–60 years), the difference was non-significant (p=0.07). The reference ranges
were 0.7–1.3 and 0.4–1.0 mg/dL for males and females respectively where the lower limit was 0.1–0.2 units less than that of
standard limits. An increase in the mean value of sCr was observed particularly in females with an increase in age. Hence
it is of interest to validate an age specific reference ranges for sCr in our population. 相似文献
115.
Subir Kumar Das Sowmya Varadhan L. Dhanya Sukhes Mukherjee S. Mohana V. Balakrishnan D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2009,24(1):60-64
Chronic pancreatitis, an irreversible inflammatory disease of the pancreas, is associated with the replacement of the destroyed
parenchyma by extended development of fibrosis. Despite marked progress in diagnostic tools, no consensus has been reached
in diagnosis of chronic pancreatitis. In this study we examined the hematological and biochemical parameters among 40 chronic
pancreatitis patients within 18 to 67 yrs. ESR level and ALP activity was elevated in 40% cases. Serum amylase activity increased
in 32 patients and it showed significant correlation with ALP (r=0.458, p=0.003), CA-19.9 (r=0.556, p<0.001), and calcium
level (r=−0.472, p=0.002). Type IV collagen level in chronic pancreatitis also elevated (164.4 ± 55.5 ng/ml) and showed negative
significant correlation with calcium level (r= −0.505, p=0.001). However, no significant correlation was observed between
amylase activity and type IV collagen (r=0.289, p= 0.07). 相似文献
116.
The purpose of this qualitative study was to explore secondary science teachers’ beliefs about multiculturalism and its implementation in their classrooms. Participants included nine secondary science teachers, with experience ranging from 1 to 15 years of teaching. Data were collected through interviews, using a semi-structured interview protocol (Kvale, 1996). The interviews were coded, analyzed, and grouped into five themes aligned with the multicultural dimensions developed by Banks and Banks (2007): Content Integration, Knowledge Construction, Prejudice Reduction, Equity Pedagogy, and Empowering School Culture. Results of the research study indicated these participants harbored a general misconception that there was only one science; traditionally that has meant a Western Modern Science (WMS: Cobern & Loving, 2001). The research also suggests the participants in this study had limited knowledge pertaining to multiculturalism in their science classrooms. To these participants, Prejudice Reduction and Equity Pedagogy were the only two dimensions that were important when teaching science content. 相似文献
117.
Yuanyuan Zhu Shuanghao Zheng Pengfei Lu Jiaxin Ma Pratteek Das Feng Su Hui-Ming Cheng Zhong-Shuai Wu 《国家科学评论(英文版)》2022,9(7)
MXenes are one of the key materials for micro-supercapacitors (MSCs), integrating miniaturized energy-storage components with microelectronics. However, the energy densities of MSCs are greatly hampered by MXenes’ narrow working potential window (typically ≤0.6 V) in aqueous electrolytes. Here, we report the fabrication of high-voltage MXene-MSCs through the efficient regulation of reaction kinetics in 2D Ti3C2Tx MXene microelectrodes using a water-in-LiCl (WIL, 20 m LiCl) salt gel electrolyte. Importantly, the intrinsic energy-storage mechanism of MXene microelectrodes in WIL, which is totally different from traditional electrolytes (1 m LiCl), was revealed through insitu and exsitu characterizations. We validated that the suppression of MXene oxidation at high anodic potential occurred due to the high content of WIL regulating anion intercalation in MXene electrodes, which effectively broadened the voltage window of MXene-MSCs. Remarkably, the symmetric planar MXene-MSCs presented a record operating voltage of 1.6 V, resulting in an exceptionally high volumetric energy density of 31.7 mWh cm−3. With the ultra-high ionic conductivity (69.5 mS cm−1) and ultralow freezing point (−57°C) of the WIL gel electrolyte, our MSCs could be operated in a wide temperature range of −40 to 60°C, and worked for a long duration even at −40°C, demonstrative of its practicality in extreme environments. 相似文献
118.
Shanshan Liu Zihan Li Ke Yang Enze Zhang Awadhesh Narayan Xiaoqian Zhang Jiayi Zhu Wenqing Liu Zhiming Liao Masaki Kudo Takaaki Toriyama Yunkun Yang Qiang Li Linfeng Ai Ce Huang Jiabao Sun Xiaojiao Guo Wenzhong Bao Qingsong Deng Yanhui Chen Lifeng Yin Jian Shen Xiaodong Han Syo Matsumura Jin Zou Yongbing Xu Xiaodong Xu Hua Wu Faxian Xiu 《国家科学评论(英文版)》2022,9(6):163-170
Two-dimensional(2D) ferromagnetic materials have been discovered with tunable magnetism and orbital-driven nodal-line features. Controlling the 2D magnetism in exfoliated nanoflakes via electric/magnetic fields enables a boosted Curie temperature(TC) or phase transitions. One of the challenges, however, is the realization of high TC2D magnets that are tunable, robust and suitable for large scale fabrication. Here, we report molecular-beam epitaxy growth of wafer-scale Fe 相似文献
119.
Madelyn H. Labella Angela J. Narayan Christopher M. McCormick Christopher D. Desjardins Ann S. Masten 《Child development》2019,90(1):227-244
A multimethod, multi-informant design was used to examine links among sociodemographic risk, family adversity, parenting quality, and child adjustment in families experiencing homelessness. Participants were 245 homeless parents (Mage = 31.0, 63.6% African American) and their 4- to 6-year-old children (48.6% male). Path analyses revealed unique associations by risk domain: Higher sociodemographic risk predicted more externalizing behavior and poorer teacher–child relationships, whereas higher family adversity predicted more internalizing behavior. Parenting quality was positively associated with peer acceptance and buffered effects of family adversity on internalizing symptoms, consistent with a protective effect. Parenting quality was associated with lower externalizing behavior only when sociodemographic risk was below the sample mean. Implications for research and practice are discussed. 相似文献
120.