检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

运动神经元在脊髓损伤后肌痉挛发生中的作用

世界核心医学期刊文摘（神经病学分册） 2005年第3期1卷 29-30页

作者： Gorassini M.A. Knash M.E. harvey p.j. 陈云春 513 HMRC Centre for Neuroscience University of Alberta Edm onton Alta. T6G 2S2 Canada

Motoneurons in the spinal cord have intrinsic voltage dependent persistent in ward currents (pICs; e.g. persistent calcium currents) that amplify synaptic inp uts by three to five fold in addition to providing a sustained excitatory driv e that allows motoneurons to fire repetitively following a brief synaptic excita tion. In this study, we examined whether prolonged involuntary muscle spasms in subjects with long term injury to the spinal cord are mediated by the activatio n of pICs in the motoneuron. To examine this in the human, we used a paired moto r unit analysis technique where the firing frequency of one motor unit of the pa ir (control unit) was used to estimate the synaptic drive to the motoneuron pool , including the drive to a second higher threshold motor unit of the pair (test unit). The degree to which a motoneuron pIC helped to sustain the discharge of a test motor unit (self sustained firing) was determined from the reduction in control unit firing at de recruitment (△F) compared with recruitment of the te st unit. This △F value corresponds to the reduction in synaptic drive needed to counteract the intrinsic pIC and, thus, was used an indirect measure of this cu rrent. In the nine motor unit pairs studied, the average estimated synaptic driv e, or control unit firing rate, required to recruit a test motor unit at the ons et of a muscle spasm was significantly higher (by 43%) than the estimated synap tic drive during derecruitment at the end of a muscle spasm. This indicated that a motoneuron pIC, and associated self sustained firing, facilitated the firing of the test units during the prolonged muscle spasms. In addition, in all subje cts tested (seven out of seven), we observed that following a muscle spasm or vo luntary contraction, spontaneous and self sustained firing of motor units could continue for many seconds, even minutes, at very low discharge rates (average 5.2 ±.1.6 Hz) with extremely low spike to spike variability (coefficient of v ar

关键词：脊髓损伤运动神经元肌痉挛肌肉阵挛运动单位钙离子流神经元群高阈尖波放电率

SARS-CoV-2 variants are associated with different clinical courses in children with MIS-C

在线全文

学校读者我要写书评

暂无评论

World journal of pediatrics 2024年第2期20卷 143-152页

作者： Andres F.Moreno Rojas Emelia Bainto Helen harvey Adriana H.Tremoulet jane C.Burns Kirsten B.Dummer Department of pediatrics Division of Pediatric CardiologyUniversity of California San Diegoand Rady Children’s Hospital3020 Children’s Way MC 5004San DiegoCA 92123USA Kawasaki Disease Research Center La JollaCAUSA Department of pediatrics Division of Pediatric Critical CareUniversity of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA Department of pediatrics University of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA

Background Recent infection with SARS‑CoV-2 in children has been associated with multisystem inflammatory syndrome in children(MIS-C).SARS‑CoV-2 has undergone different *** publications exist about specific variants and their correlation with the severity of *** This was a single-center,retrospective study including all patients admitted with MIS-C at Rady Children’s Hospital-San Diego between May 2020 and March *** epidemiologic data,including viral genomic information,were obtained from public ***,clinical presentation,laboratory values,and outcomes were obtained from electronic medical *** The analysis included 104 pediatric *** MIS-C waves were *** variants in San Diego during the first wave included clades 20A to *** the second wave,there were variants from clades 20A to C,20G,21C(Epsilon),20I(Alpha),and 20j(Gamma).The third wave had Delta strains(clades 21A,21I,and 21j),and the fourth had Omicron variants(clades 21K,21L,and 22C).MIS-C presented with similar symptoms and laboratory findings across all *** patients were admitted to the pediatric intensive care unit(pICU)(74%)and required inotropic support(63%)during the second *** of the patients required mechanical circulatory support,and only two required invasive ventilatory *** was no *** The various strains of SARS-CoV-2 triggered MIS-C with differing severities,with the second wave having a more severe clinical *** the differences in disease severity across variants were due to changes in the virus or other factors remains unknown.

关键词： Complications COVID-19 MIS-C SARS-CoV-2 variants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

冠状动脉搭桥术后抑郁的性别差异

世界核心医学期刊文摘(心脏病学分册) 2006年第4期 37-37页

作者： Mitchell R.H.B. Robertson E. harvey p.j. 柴大军 Toronto General Hospital EN-7-233 200 Elizabeth St Toronto Ont. M5G 2C4 Canada

Background: previous research suggests that after coronary artery bypass graft(CABG)surgery, women fare worse than men. This study investigates sex differences in depression during recovery from CABG surgery. Methods: We followed 137 patients(72 men, 65 women)undergoing elective isolated first CABG surgery between july 2003 and April 2004. patients were interviewed ≤28 days before surgery and between 6 and 12 weeks after surgery. patients completed a structured diagnostic interview for major depressive disorder(MDD)and the Beck Depression Inventory(BDI). Clinical data were retrieved from patient charts. Results: prevalence of MDD before surgery was 28.2%, but decreased to 16.4%after surgery(p=.038). Women had significantly more depressive symptoms than men pre-CABG, with a mean BDI of 12.5(95%CI 10.6-14.4)for women versus 8.0(95%CI 6.3-9.8)for men(p=.0001), but not post-CABG. There was a significant sex-by-time interaction with depre ssive symptoms in women improving almost 6-fold more than in men, with BDI chan ge scores of 4.1(95%CI 2.0-6.1)for women versus 0.7(95%CI-1.0-2.5)for men(p =.008). The interaction remained significant after adjusting the model for the p redetermined baseline characteristics education, social support, and operative r isk. Conclusions: Women had more depressive symptoms than men pre-CABG, but imp roved to a level comparable to men post-CABG. Women benefited from CABG as much or more than men in terms of their mental health. preoperative depressive sympt oms should not preclude women from CABG surgery.

关键词：抑郁症状术前男性女性 CABG 性别差异差异(心理学)

A route to enhanced performance for the petawatt beamlines of the Orion laser facility

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

High power Laser Science and Engineering 2022年第3期10卷 11-18页

作者： E.j.harvey AWE AldermastonReadingRG74PRUK

The Orion laser facility at AWE provides multiple beams to target delivering synchronized pulses at both nanosecond and sub-picosecond *** the latter,the peak power approaches the petawatt *** paper presents a conceptual design for potential development of these *** would deliver a significant enhancement of performance at the fundamental *** addition,a new approach is described for the management of frequency conversion at high intensity,which may allow significantly enhanced performance at the second harmonic also.

关键词： chirped pulse amplification frequency doubling temporal contrast

Structural and Mechanistic Aspects of Mn-oxo and Co-based Compounds in Water Oxidation Catalysis and potential Applications in Solar Fuel production

在线全文

学校读者我要写书评

暂无评论

journal of Integrative plant Biology 2010年第8期52卷 704-711页

作者： harvey j.M.Hou Department of Chemistry and Biochemistry University of Massachusetts Dartmouth North Dartmouth

To address the issues of energy crisis and global warming, novel renewable carbon-free or carbon-neutral energy sources must be identified and developed. A deeper understanding of photosynthesis is the key to provide a solid foundation to facilitate this transformation. To mimic the water oxidation of photosystem II oxygen evolving complex, Mn-oxo complexes and Co-phosphate catalytic material were discovered in solar energy storage. Building on these discoveries, recent advances in solar energy conversion showed a compelling working principle by combing the active Mn-oxo and Co-based catalysts in water splitting with semiconductor heteronanostructures for effective solar energy harnessing. In this review the appealing systems including Mn-oxo tetramer/Nafion, Mn-oxo dimer/TiO2, Mn-oxo oligomer/WO3, Co-pi/Fe2O3, and Co-pi/ZnO are summarized and discussed. These accomplishments offer a promising framework and have a profound impact in the field of solar fuel production.

关键词： Mn Structural and Mechanistic Aspects of Mn-oxo and Co-based Compounds in Water Oxidation Catalysis and potential Applications in Solar Fuel production II Figure

FETAL LUNG MATURITY pREDICTION BY pLACENTAL GRADE AND BIpARIETAL DIAMETER

在线全文

学校读者我要写书评

暂无评论

中华医学杂志(英文版) 1985年第8期98卷 561-564页

作者：邹玲 harvey A Gabert Willam j McGanity Department of Obstetrics and Gynecology Affiliated Hospital Shandong Medical College Jinan China

Fetal lung maturity was studied in 108 singleton pregnancies. placental grades and biparietal diameter measurements were recorded. Of these. 58 also had amniocentesis for lecithin-sphingomyelin ratio, phosphatidylglycerol and foam test. Factors such as maternal age, race, parity, and fetal sex were also studied to see if they influenced the placental grading. placental grading appeared to be more advanced among those with first gravida who subsequently gave birth to a male offspring. When the placental grade was Ⅰ, Ⅱ, or Ⅲ and the biparietal diameter ≥ 8.7 cm, fetal lungs were all biochemically mature and none of the neonates developed respiratory distress syndrome after delivery. Utilizing both placental grading and biparietal diameter, fetal lung maturity could be predicted accurately, making amniocentesis unnecessary.

关键词：

Evolution of breast cancer therapeutics: Breast tumour kinase's role in breast cancer and hope for breast tumour kinase targeted therapy

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World journal of Clinical Oncology 2014年第3期5卷 299-310页

作者： Haroon A Hussain Amanda j harvey Brunel Institute for Cancer Genetics and pharmacogenomics Biosciences Brunel University (London)

There have been significant improvements in the detection and treatment of breast cancer in recent decades. However, there is still a need to develop more effective therapeutic techniques that are patient specific with reduced toxicity leading to further increases in patients' overall survival; the ongoing progress in understanding recurrence, resistant and spread also needs to be maintained. Better understanding of breast cancer pathology, molecular biology and progression as well as identification of some of the underlying factors involved in breast cancer tumourgenesis and metastasis has led to the identification of novel therapeutic targets. Over a number of years interest has risen in breast tumour kinase(Brk) also known as protein tyrosine kinase 6; the research field has grown and Brk has been described as a desirable therapeutic target in relation to tyrosine kinase inhibition as well as disruption of its kinase independent activity. This review will outline the current "state of play" with respect to targeted therapy for breast cancer, as well as discussing Brk's role in the processes underlying tumour development and metas-tasis and its potential as a therapeutic target in breast cancer.

关键词： Breast tumour kinase protein tyrosine kinase 6 Breast neoplasms Targeted molecular therapy Intracellular signaling peptides and proteins protein kinase inhibitors

Roles of manganese in photosystem II dynamics to irradiations and temperatures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers in Biology 2013年第3期8卷 312-322页

作者： Xuejing HOU harvey j. M. HOU Department of Chemistry and Biochemistry University of Massachusetts Dartmouth North Dartmouth MA 02747 USA Department of physical Sciences Alabama State University Montgomery AL 36104 USA

The most amazing chemistry is the light-driven water splitting reaction occurred in the oxygen-evolving complex of phototsystem II in higher plants, green algae, and cyanobacteria. Mn, in the form of Mn4CaOs cluster in photosystem II, is responsible for the catalytic water splitting reaction as well as plays roles in photosystem II dynamics to irradiation and temperatures. Manganese hypothesis of UV-initiated photoinhibition as a direct target is established, and thermal inactivation of photosystem II involves the valence and structural changes of manganese. Recent progresses in understanding the roles of manganese in photoinhibition especially under UV light and in thermal inactivation including elevated temperatures using synthetic models and native pS II complexes are summarized and evaluated. potential problems and possible solutions are discussed and presented.

关键词： photosynthesis manganese photosystem II irradiation temperature stress

Methane production from Sargassum muticum:effects of seasonality and of freshwater washes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

能源与人工环境(英文) 2021年第3期2卷 235-242页

作者： Supattra Maneein john j.Milledge patricia j.harvey Birthe V.Nielsen Algae Biotechnology University of GreenwichChatham MaritimeME44TBUK

Biogas production from Sargassum muticum,an invasive seaweed species to Europe,is hampered by low methane(CH_(4))yields during anaerobic digestion(AD),but causes are *** research is the first to demonstrate the impact of extensive freshwater washing of spring-and summer-harvested *** on the CH_(4)production rates and the biochemical methane potential(BMp).The findings reveal that the rate profile of CH_(4)production is affected by extensively washing the seaweed and is dependent on ***-harvested *** had higher initial CH_(4)production rates compared to summer-harvested *** spring-harvested ***,the initial rate of CH_(4)production was lowered by extensive *** contrast,extensively washed summer-harvested *** had a higher degradation rate and CH_(4)production rate relative to its non-extensively washed *** highest CH_(4)potentials accumulated by the treated and non-treated *** are,however,statistically similar and not influenced by seasonality or extensive washing(p>0.05).potential causes for differences in the rate of CH_(4)production between summer-and spring-harvested *** are *** differences in CH_(4)production from treated summer-and spring-harvested *** acts as a stepping stone to understanding the causes for low CH_(4)yields,which could allow for further enhancements in CH_(4)production from ***.

关键词： Seaweed Biogas Biofuels Seasonality Washing