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排序方式: 共有810条查询结果,搜索用时 31 毫秒
151.
IV Gannushkina ML Farago AL Antelava MV Baranchikova NN Ve?ko 《Canadian Metallurgical Quarterly》1998,(5):16-22
To reveal the hemodynamic effect of plasma DNA, the authors measured the concentrations of plasma DNA, the length of its molecular fragments, and hemodynamic resistance/Toms effect. The Toms effect was detected in all blood samples from 10 healthy donors and 39 patients without acute stroke caused by atherosclerosis of the head great arteries with and without arterial hypertension. There was a clear inverse relationships between the plasma concentrations of DNA which had only long-molecular fragments in healthy persons and the hemodynamic resistance of its blood flow samples. The patient blood plasma had significant increased DNA concentrations but their molecular fragments were long and short. Inverse relationships between the plasma DNA concentration and the hemodynamic resistance of the patients' blood flow samples had a less correlation coefficient due to the high proportion of short DNA molecular fragments. The Toms effect was shown in the DNA solution prepared only from human funic blood where the DNA molecular fragments were long. The Toms effect was absent in the solutions prepared from the commercial cattle or salmon sperm DNA which contained shorter DNA molecular fragments. It is concluded that plasma DNA has a hemodynamic effect and the origin of long-molecular fragments of DNA which is typical for healthy young persons and short DNA molecular fragments that additionally appear in patients with vascular disorders is different. 相似文献
152.
153.
Yiping He Xiaomin Yao Nereus W. Gunther IV Yanping Xie Shu-I Tu Xianming Shi 《Food Analytical Methods》2010,3(4):321-329
A multiplex real-time PCR (qPCR) assay was developed for simultaneous detection and differentiation of the three most important
Campylobacter species in chickens. Three novel sets of PCR primers and TaqMan probes were designed to amplify the unique DNA sequences
within the hipO, cdtA, and pepT genes which are specific to Campylobacter jejuni, Campylobacter coli, and Campylobacter lari, respectively. To avoid competition in the multiple target amplifications, the concentrations of primers and probes were
optimized. By using the optimized qPCR conditions together with a minor-groove binding probe of pepT, amplification efficiency greater than 92% and detection sensitivity of 38 genome copies/reaction have been achieved for
all three targets. The assay was highly specific for C. jejuni, C. coli, and C. lari with testing of 33 Campylobacter strains and 20 non-Campylobacter strains. In chicken samples spiked with known quantities of Campylobacter cells, the assay was able to detect 1 CFU/g after a 24-h enrichment. Application of the assay in food was further evaluated
using 21 fresh chicken samples obtained from local supermarkets. The results revealed that, after a 24-h or 48-h enrichment,
14 samples (66.7%) were positive for C. jejuni, five samples (23.8%) were positive for C. coli, and none of the samples was contaminated by C. lari. Taken together, the multiplex qPCR assay combined with an enrichment step is a sensitive, species-specific, and non-labor-intensive
method suitable for rapid detection of C. jejuni, C. coli, and C. lari in chicken samples. 相似文献
154.
Atomic Energy - The real and important problem of choosing a location for NPP sites is examined. It is shown that the methodology of VAB-3 level-3 probabilistic safety analysis can be used in... 相似文献
155.
Verrill M. Norwood IV Robert W. Huigens III 《Chembiochem : a European journal of chemical biology》2019,20(18):2273-2297
Indole-containing compounds demonstrate an array of biological activities relevant to numerous human diseases. The biological activities of diverse indole-based agents are driven by molecular interactions between indole agent and critical therapeutic target. The chemical inventory of medicinally useful or promising indole compounds spans the entire structural spectrum, from simple synthetic indoles to highly complex indole alkaloids. In an analogous fashion, the chemistry behind the indole heterocycle is unique and provides rich opportunities for extensive synthetic chemistry, enabling the construction and development of novel indole compounds to explore chemical space. This review will present heterocyclic chemistry of the indole nucleus, indole compounds of clinical use, complex indole alkaloids and indole-inspired discovery efforts by multiple research groups interested in using novel indole-containing small molecules to drive discoveries in human biology and medicine. 相似文献
156.
Bessolov V. N. Kompan M. E. Konenkova E. V. Panteleev V. N. Rodin S. N. Shcheglov M. P. 《Technical Physics Letters》2019,45(6):529-532
Technical Physics Letters - Two different approaches to epitaxy of 4-μm-thick layers of polar GaN(0001) and semipolar GaN(10 $$\bar {1}$$ 1) on a V-shaped nanostructured Si(100) substrate with... 相似文献
157.
Karane M. M. S. Panteleev A. V. 《Journal of Computer and Systems Sciences International》2022,61(5):751-775
Journal of Computer and Systems Sciences International - The problem of finding the optimal control of bundles of trajectories of continuous deterministic systems with incomplete feedback is... 相似文献
158.
IuG Suchkov IV Khudiakov EN Emel''ianenko MI Levi VI Pushkareva IIu Suchko VIu Litvin EV Kulesh RS Zotova AL Gintsburg 《Canadian Metallurgical Quarterly》1997,17(4):42-46
The purpose of this study was to find criteria characteristic for patients in need of care and social services. The criteria should serve as a guideline for patients and staff to facilitate care planning before discharge. The sample consisted of 49 patients, born before 1925, in need of emergency inpatient treatment, admitted to medical- or orthopaedic wards. Data of the patient's self care needs were collected by interviews, assessment of self care status and need of treatment. The patients could be divided into three groups depending on type of discharge. Group A (n = 27) discharged home, group B (n = 7) discharged to geriatric clinic and group C (n = 15) discharged and in need of further care and social services. Criteria indicating the patients further assistance from the community were in group C (medical- and orthopaedic wards) deficit in daily living activities and locomotion. Group B had an increased need of support from the physiotherapist and the occupational therapist, in locomotion as well as daily living activities The physician's assessment showed that the criteria behind the decision "no further medical treatment appropriate" and "ready for discharge" were not related to medical impairment but to lack of self care, need of care, rehabilitation and social services. 相似文献
159.
NN Kudriavtseva IV Bakshtanovskaia DF Avgustinovich 《Canadian Metallurgical Quarterly》1997,47(1):86-97
The influence of repeated experience of aggression in daily intermale confrontations on individual and social behaviour was studied in male mice of C57BL/6J (C57) and CBA/Lac (CBA) strains. Repeated experience of aggression led to a decrease of emotionality in males of highly emotional CBA strain and increase in exploratory activity in the open field and exploratory activity tests, decrease of immobility time in Porsolt's test and pain sensitivity estimated by the "hot plate" test. Low emotional C57 males did not change their individual behaviour in different situations under the influence of repeated experience of aggression. However, aggressive C57 mice demonstrated anxiety-like behaviour estimated in the plus-maze test. In the partition test aggressive mice of both strains showed an increase in communicative level (as a reaction to a familiar male) in comparison with their behaviour before aggressive confrontations. Behavioural reaction to a receptive female under unfamiliar conditions decreased which testified to a decrease in sexual motivation. It is concluded that formation of the aggressive type of social behaviour is accompanied by changes in the individual and social behaviour of male mice. Characteristics of these changes are genetically determined and depend on the duration of confrontations. 相似文献
160.
Miniaturized,Battery‐Free Optofluidic Systems with Potential for Wireless Pharmacology and Optogenetics 下载免费PDF全文
Kyung Nim Noh Sung Il Park Raza Qazi Zhanan Zou Aaron D. Mickle Jose G. Grajales‐Reyes Kyung‐In Jang Robert W. Gereau IV Jianliang Xiao John A. Rogers Jae‐Woong Jeong 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(4)
Combination of optogenetics and pharmacology represents a unique approach to dissect neural circuitry with high specificity and versatility. However, conventional tools available to perform these experiments, such as optical fibers and metal cannula, are limited due to their tethered operation and lack of biomechanical compatibility. To address these issues, a miniaturized, battery‐free, soft optofluidic system that can provide wireless drug delivery and optical stimulation for spatiotemporal control of the targeted neural circuit in freely behaving animals is reported. The device integrates microscale inorganic light‐emitting diodes and microfluidic drug delivery systems with a tiny stretchable multichannel radiofrequency antenna, which not only eliminates the need for bulky batteries but also offers fully wireless, independent control of light and fluid delivery. This design enables a miniature (125 mm3), lightweight (220 mg), soft, and flexible platform, thus facilitating seamless implantation and operation in the body without causing disturbance of naturalistic behavior. The proof‐of‐principle experiments and analytical studies validate the feasibility and reliability of the fully implantable optofluidic systems for use in freely moving animals, demonstrating its potential for wireless in vivo pharmacology and optogenetics. 相似文献