检索结果-南通市图书馆

Review of nonalcoholic fatty liver disease in women with polycystic ovary syndrome

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World journal of Gastroenterology 2014年第39期20卷 14172-14184页

作者： carly E Kelley Ann j Brown Anna Mae Diehl Tracy L Setji Department of Medicine Division of Endocrinology Duke University Medical Center Durham NC 27710 United States Department of Medicine Division of Gastroenterology Duke University Medical Center Durham NC 27710 United States

Polycystic ovary syndrome(PCOS) is the most common endocrine disorder in reproductive-aged women. Women with PCOS frequently have metabolic complications including insulin resistance(IR), early diabetes, hypertension and dyslipidemia. Recent studies have demonstrated an association between PCOS and another metabolic complication: nonalcoholic fatty liver disease(NAFLD). NAFLD occurs as a result of abnormal lipid handling by the liver, which sensitizes the liver to injury and inflammation. It can progress to nonalcoholic steatohepatitis(NASH), which is characterized by hepatocyte injury and apoptosis. With time and further inflammation, NASH can progress to cirrhosis. Thus, given the young age at which NAFLD may occur in PCOS, these women may be at significant risk for progressive hepatic injury over the course of their lives. Many potential links between PCOS and NAFLD have been proposed, most notably IR and hyperandrogenemia. Further studies are needed to clarify the association between PCOS and NAFLD. In the interim, clinicians should be aware of this connection and consider screening for NAFLD in PCOS patients who have other metabolic risk factors. The optimal method of screening is unknown. However, measuring alanine aminotransferase and/or obtaining ultrasound on high-risk patients can be considered. First line treatment consists of lifestyle interventions and weight loss, with possible pharmacologic interventions in some cases.

关键词： Polycystic ovary syndrome Fatty liver Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis

NEXT NEAREST NEIGHBOR EFFECT ON TETRAHEDRAL FERROUS AND OCTAHEDRAL FERRIC IRON IN CHROMITE

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 1986年第8期29卷 889-896页

作者：李哲,j.G.stevens Institute of Geology Academia Sinica Beijing Mssbauer Effect Data Center University of North Carolina Asheville U. S. A.

Four chromites have been studied by using Mssbauer spectroscopy. Of the spectra of four chromites studied, three spectra aro fitted to three or four Fe2+doublets in the tetrahedral A sites and one or two Fe3+doublets in the tetrahedral A sites and octahedral B sites. The fourth spectrum is fitted to one Fe3+doublet in the A sites and two Fe3+doublets in tho B sites. Constant isomer shifts of approximately 0.9 mm/s for Fe2+ions in the A sites and 0.3 mm/s for Fe3+ions in the B sites as well as gradual changing quadrupole splitting for both of the A sites and the B sites are obtained. The binomial distributions in the B sites are ealeulated. Next nearest neighbor effect is used to explain the multiple doublets caused by Fe2+ions in the A sites in the spectra of chromites Ⅰ, Ⅱ, Ⅲ and by Fe3+ions in the B sites in the spectrum of chromite Ⅳ.

关键词： tetrahedral octahedral fitted NEXT neighbor explain nearest splitting fourth umber

Mechanisms underlying feed intolerance in the critically ill: Implications for treatment

同方期刊数据库评论

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 Gastroenterology 2007年第29期13卷 3909-3917页

作者： Adam Deane Marianne j Chapman Robert j Fraser Laura K Bryant carly Burgstad Nam Q Nguyen Intensive Care Unit Royal Adelaide Hospital Adelaide South Australia Discipline of Medicine University of Adelaide and Investigation and Procedures Unit Repatriation General Hospital Adelaide South Australia Investigation and Procedures Unit Repatriation General Hospital Adelaide South Australia Department of Gastroenterology and Hepatology Royal Adelaide Hospital Adelaide South Australia

Malnutrition is associated with poor outcomes in critically ill patients. Although nutritional support is yet to be proven to improve mortality in non-malnourished critically ill patients, early enteral feeding is considered best practice. However, enteral feeding is often limited by delayed gastric emptying. The best method to clinically identify delayed gastric emptying and feed intolerance is unclear. Gastric residual volume （GRV） measured at the bedside is widely used as a surrogate marker for gastric emptying, but the value of GRV measurement has recently been disputed. While the mechanisms underlying delayed gastric emptying require further investigation, recent research has given a better appreciation of the pathophysiology. A number of pharmacological strategies are available to improve the success of feeding. Recent data suggest a combination of intravenous metoclopramide and en/thromycin to be the most successful treatment, but novel drug therapies should be explored. Simpler methods to access the duodenum and more distal small bowel for feed delivery are also under investigation. This review summarises current understanding of the factors responsible for, and mechanisms underlying feed intolerance in critical illness, together with the evidence for current practices. Areas requiring further research are also highlighted.

关键词： Critical illness Enteral nutrition Gastric emptying Gastric motility Gastrointestinal hormones Metoclopramide Erythromycin Prokinetic therapy

Thermodynamic functions of ZrW_2O_8 from its heat capacity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 563-567页

作者： ji FengMin DAI XianXi stevens R GOATES j B College of Sciences Ningbo University of TechnologyNingbo 315211China Research Group of Quantum Statistics and Methods of Theoretical Physics Department of PhysicsFudan University Shanghai 200433China Department of Chemistry Brigham Young UniversityProvoUT 84602USA

It is interesting to maximize the amount of information we can obtain from one experiment on a single sample. In obtaining all the thermodynamic properties of some materials from their experimental heat capacity data only, we aim to get the tempera- ture-independent energy spectrum. However, all the practical measured energy spectra depend on the temperature of experi- ments. One promising method to obtain the temperature-independent energy spectrum is to solve the so-called specific heat-phonon spectrum inversion （SPI） problem. Here we show, by developing a new practical solution method of SPI, the phonon spectrum of the negative thermal expansion material ZrW208 is obtained. This phonon spectrum is tempera- ture-independent and almost method independent. Hence all the thermodynamic properties of ZrW208, such as thermodynamic potential, entropy, Helmholtz free energy, etc. are obtained by heat capacity only.

关键词： holographic studies instability problems specific heat-phonon spectrum inversion problem DMF method

Impact of bolus volume on small intestinal intra-luminal impedance in healthy subjects

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World journal of Gastroenterology 2010年第17期16卷 2151-2157页

作者： Nam Q Nguyen Laura K Bryant carly M Burgstad Robert j Fraser Daniel Sifrim Richard H Holloway Department of Gastroenterology & Hepatology Royal Adelaide HospitalAdelaide 5000Australia Investigation and Procedures Unit Repatriation General HospitalDaw Park 5041Australia Department of Medicine Centre for Gastroen-terological ResearchK.U.LeuvenLeuven 3000Belgium

AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance ***: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 *** subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline,over ≥ 3 consecutive segments within 10 s of bolus injection.A minor or major imped-ance event was defined as a duration of impedance drop jor impedance events (≥ 10 mL boluses = 63%,3 mL boluses = 17%,and < 3 mL boluses = 0%,P = 0.02).CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.

关键词： Bolus volume Health Impedance Luminal flow Small intestine

Necklaces of PT-symmetric dimers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2018年第5期6卷 I0012-I0018页

作者： D.j.NODAL stevens BENjAMIN jARAMILLO AVILA B.M.RODRIGUEZ-LARA Tecnologico de Monterrey Escuela de Ingenieria y CienciasAve.Eugenio Garza Sada 2501MonterreyN.L.64849Mexico CONACYT-Instituto Nacional de Astroffsica Optica y ElectronicaCalle Luis Enrique Erro No.1Sta.Ma.TonantzintlaPue.CP 72840Mexico Instituto Nacional de Astroffsica Optica y ElectronicaCalle Luis Enrique Erro No.1Sta.Ma.TonantzintlaPue.CP 72840Mexico

We study light propagation through cyclic arrays, composed by copies of a given PT-symmetric dimer, using a group theoretical approach and finite dement modeling. The theoretical mode-coupling analysis suggests the use of these devices as output port replicators where the dynamics is controlled by the impinging light field. This is confirmed in good agreement with finite element propagation in an experimentally feasible necklace of passive PT-symmetric dimers constructed from lossy and lossless waveguides.

关键词： Necklaces PT-symmetric dimers

Individual variation in ballooning dispersal by black widow spiderlings： The effects of family and social rearing

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2015年第3期61卷 520-528页

作者： j. Chadwick jOHNSON Rebecca HALPIN Dale stevens II Annika VANNAN jesse LAM Katie BRATSCH School of Mathematical and Natural Sciences (2352) Arizona State University at the West Campus Glendale AZ 85306 USA

Individual behavioral variation is ubiquitous across taxa and important to understand if we wish to fully use beha- vioral data to understand the ecology and evolution of organisms. Only recently have studies of individual variation in dispersal behavior become a focus of research. A better understanding of individual variation in dispersal behavior is likely to improve our understanding of population dynamics. In particular, the dynamics of critically small populations （endangered species） and large populations （pest species） may be driven by unique dispersal variants. Here we documented individual variation in the ballooning dispersal behavior of Western black widow spiderlings Latrodectus hesperus, an urban pest species found in superabundant in- festations throughout cities of the desert Southwest USA. We found a great deal of family-level variation in ballooning dispersal, and this variation was highly consistent （repeatable） across time. Maternal egg investment was a poor predictor of this ballooning dispersal. Instead, we show that spiderlings reared in isolation are significantly slower to disperse than spiderlings raised in a more natural setting surrounded by full siblings. Thus, our study examines a widespread but poorly understood dispersal behavior （ballooning）, and suggests urban pest population dynamics are likely driven by the interaction of variation in individuals, families and social environments

关键词： Individual variation Dispersal Spiders Ballooning Social rearing

Exploring nationally and regionally defined models for large area population mapping

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International journal of Digital Earth 2015年第12期8卷 989-1006页

作者： A.E.Gaughan F.R.stevens C.Linard N.N.Patel A.j.Tatem Department of Geography and Geosciences University of LouisvilleLouisvilleKYUSA Biological Control and Spatial Ecology UniversitéLibre de BruxellesBrusselsBelgium Department of Geography and Geoinformation Science George Mason UniversityFairfaxVAUSA Department of Geography and Environment University of SouthamptonSouthamptonUK Fogarty International Center National Institutes of HealthBethesdaMDUSA Flowminder Foundation StockholmSweden

Interactions between humans,diseases,and the environment take place across a range of temporal and spatial scales,making accurate,contemporary data on human population distributions critical for a variety of *** for disaggregating census data to finer-scale,gridded population density estimates continue to be refined as computational power increases and more detailed census,input,and validation datasets become ***,the availability of spatially detailed census data still varies widely by *** this study,we develop quantitative guidelines for choosing regionally-parameterized census count disaggregation models over country-specific *** examine underlying methodological considerations for improving gridded population datasets for countries with coarser scale census data by investigating regional versus country-specific models used to estimate density surfaces for redistributing census *** is given to the spatial resolution of input census data using examples from East Africa and Southeast *** suggest that for many countries more accurate population maps can be produced by using regionally-parameterized models where more spatially refined data exists than that which is available for the focal *** study highlights the advancement of statistical toolsets and considerations for underlying data used in generating widely used gridded population data.

关键词： human population modeling random forest regression dasymetric mapping gridded population datasets

Magnetic anchor guidance for endoscopic submucosal dissection and other endoscopic procedures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World journal of Gastroenterology 2017年第16期23卷 2883-2890页

作者： Mohamed Mortagy Neal Mehta Mansour A Parsi Seiichiro Abe Tyler stevens john j Vargo Yutaka Saito Amit Bhatt Department of Internal Medicine Homer Stryker MD School of MedicineWestern Michigan UniversityKalamazooMI 49008United States Department of Internal Medicine Medicine InstituteCleveland ClinicClevelandOH 44195United States Department of Gastroenterology and Hepatology Digestive Disease InstituteCleveland ClinicClevelandOH 44195United States Endoscopy Division National Cancer Center HospitalTokyo 104-0045Japan

Endoscopic submucosal dissection(ESD) is a wellestablished, minimally invasive treatment for superficial neoplasms of the gastrointestinal tract. The universal adoption of ESD has been limited by its slow learning curve, long procedure times, and high risk of complications. One technical challenge is the lack of a second hand that can provide traction, as in conventional surgery. Reliable tissue retraction that exposes the submucosal plane of dissection would allow for safer and more efficient dissection. Magnetic anchor guided endoscopic submucosal dissection(MAGESD) has potential benefits compared to other current traction methods. MAG-ESD offers dynamic tissue retraction independent of the endoscope mimicking a surgeon's "second hand". Two types of magnets can be used: electromagnets and permanent magnets. In this article we review the MAG-ESD technology, published work and studies of magnets in ESD. We also review the use of magnetic anchor guidance systems in natural orifice transluminal endoscopic surgery and the idea of magnetic non-contact retraction using surface ferromagentization. We discuss the current limitations, the future potential of MAG-ESD and the developments needed for adoption of this technology.

关键词： Endoscopic submucosal dissection Gastric cancer Magnetic anchor guidance Esophageal cancer Magnets Traction Natural orifice transluminal endoscopic surgery