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排序方式: 共有308条查询结果,搜索用时 13 毫秒
91.
JONATHAN M. LEVY M.D. PAUL W. NYKAMP M.D. GERALD JOGERST M.D. †FRED S. YERGER M.D. ‡NICHOLAS R. PITHA M.D. JACK O. McFARLAND M.D. 《The American journal of gastroenterology》1978,70(3):298-301
Computed tomogriiphy (CT) has been successfully applied to the diagnosis of abnormalities of the solid abdominal organs. In a patient with liver abscess, CT was used to direct percutaneous drainage of a loeulated portion of the abscess. The use of CT for liiopsy and treatment of intra-abdominal diseases should become more common as sean time decreases. 相似文献
92.
NICHOLAS KIPSHIDZE M.D. PH.D. PARAMJITH S. CHAWLA M.D. † 《Journal of interventional cardiology》1999,12(5):329-337
The development of the autoperfusion balloon catheter provided the ability to perform prolonged balloon inflations during angioplasty procedures. For a number of years the autoperfusion balloon catheter was successfully used to treat acute complications of percutaneous coronary interventions. However, with the advent of stent implantation procedures and the use of platelet glycoprotein IIb/IIIa receptor inhibitors, the role of autoperfusion balloon angioplasty has decreased. However, the perfusion balloon may have an important role in angioplasty and/or stenting of coronary lesions with unfavorable coronary anatomy and also in carotid angioplasty. The perfusion balloon also may be helpful for the treatment of in-stent restenosis. In the future the autoperfusion balloon or its principle may hold promise in emerging interventions, such as gene therapy and vascular brachytherapy where prolonged interrupted of coronary circulation is required. 相似文献
93.
RICHARD JOHN SCHILLING M.B. D. WYN DAVIES M.D. NICHOLAS SIMON PETERS M.D. 《Journal of cardiovascular electrophysiology》1998,9(9):921-933
Noncontact Mappin g of VT During Sinus Rhythm. Introduction : Regions of the diseased ventricle that activate abnormally during sinus rhythm (SR) may be the areas of slow and disorganized conduction that form the diastolic pathway through which reentry may occur during ventricular tachycardia (VT).
Methods and Results : We examined features of electrograms recorded during SR that might indicate a site suitable for ablation of VT using a noncontact mapping system, which enables reconstruction of > 3,000 electrograms. Preablation SR electrogram characteristics at sites of successful radiofrequency ablation (RFA) were examined in 13 patients with 53 VTs. Timing of onset, lateness of activity, electrogram duration, and number of baseline crossing events of reconstructed electrograms at the sites of successful RFA were compared with the electrograms of latest onset, latest activity, longest duration, and most baseline crossing events of all ventricular sites. Onset of activation at sites of successful RFA were 26.9 ± 25.2 msec (mean ± SD) earlier than (and 2.9 ± 1.7 cm away from) the site of latest onset of SR activation. Electrogram duration at sites of successful RFA was 83%± 14.6% of (and 4.3 ± 1.8 cm away from) the longest electrogram. The baseline crossing events at sites of successful RFA were 53%± 22% of (and 4.9 ± 1.9 cm away from) the most fractionated electrogram. The latest activity at sites of successful RFA was 21.6 ± 24.8 msec earlier than (and 4.3 ± 1.6 cm away from) the site of latest activity.
Conclusion : Although the site of latest onset of endocardial activation during SR proved to be the most sensitive indicator, the characteristics of SR electrograms did not usefully predict successful ablation sites. 相似文献
Methods and Results : We examined features of electrograms recorded during SR that might indicate a site suitable for ablation of VT using a noncontact mapping system, which enables reconstruction of > 3,000 electrograms. Preablation SR electrogram characteristics at sites of successful radiofrequency ablation (RFA) were examined in 13 patients with 53 VTs. Timing of onset, lateness of activity, electrogram duration, and number of baseline crossing events of reconstructed electrograms at the sites of successful RFA were compared with the electrograms of latest onset, latest activity, longest duration, and most baseline crossing events of all ventricular sites. Onset of activation at sites of successful RFA were 26.9 ± 25.2 msec (mean ± SD) earlier than (and 2.9 ± 1.7 cm away from) the site of latest onset of SR activation. Electrogram duration at sites of successful RFA was 83%± 14.6% of (and 4.3 ± 1.8 cm away from) the longest electrogram. The baseline crossing events at sites of successful RFA were 53%± 22% of (and 4.9 ± 1.9 cm away from) the most fractionated electrogram. The latest activity at sites of successful RFA was 21.6 ± 24.8 msec earlier than (and 4.3 ± 1.6 cm away from) the site of latest activity.
Conclusion : Although the site of latest onset of endocardial activation during SR proved to be the most sensitive indicator, the characteristics of SR electrograms did not usefully predict successful ablation sites. 相似文献
94.
HENRY D. ROYAL M.D. NICHOLAS PAPANICOLAOU M.D. MICHAEL BETTMANN M.D. BARBARAJ McNEIL M.D. Ph.D. 《The American journal of gastroenterology》1980,74(2):173-175
In this case of active gastrointestinal bleeding, radionuclide blood pool scintigraphy localized the bleeding to the region of the duodenum. Celiac and superior and inferior mesenteric arteriography did not identify the site of bleeding: however, bleeding duodenal varices were found at the time of surgery. The potential role of radionuclides in the management of patients with gastrointestinal bleeding, especially with bleeding from varices. is discussed. 相似文献
95.
JAN P PIEK NICHOLAS C BARRETT MURRAY J DYCK ANGELA M REIERSEN 《Developmental medicine and child neurology》2010,52(2):200-204
Aim It has been suggested that one approach to identifying motor impairment in children is to use the Child Behavior Checklist (CBCL) as a screening tool. The current study examined the validity of the CBCL in identifying motor impairment. Method A total of 398 children, 206 females and 192 males, aged from 3 years 9 months to 14 years 10 months were assessed on the McCarron Assessment of Neuromuscular Development to determine their motor ability. Parents completed the CBCL. Results The ‘Clumsy’ item on the CBCL was found to predict motor ability independent of the child’s age, sex, and scores on other items of the CBCL. However, the sensitivity of the ‘Clumsy’ item in terms of identifying motor impairment was found to be a low 16.7% compared with specificity of 93.2%. The item ‘Not liked’ was also found to be a significant predictor of motor impairment. Interpretation Although the ‘Clumsy’ and ‘Not liked’ items were found to have a relationship with motor ability, they should not be relied upon to categorize children as motor impaired versus not impaired. It is possible that these items may be better indicators of motor impairment in children with developmental disorders such as attention‐deficit‐hyperactivity disorder, but clinical samples are needed to address this. 相似文献
96.
97.
CÉCILE KNAI MARK PETTICREW NICHOLAS MAYS SIMON CAPEWELL REBECCA CASSIDY STEVEN CUMMINS ELIZABETH EASTMURE PATRICK FAFARD BENJAMIN HAWKINS JØRGEN DEJGÅRD JENSEN SRINIVASA VITTAL KATIKIREDDI MODI MWATSAMA JIM ORFORD HEIDE WEISHAAR 《The Milbank quarterly》2018,96(3):472-498
Policy Points:
- Worldwide, more than 70% of all deaths are attributable to noncommunicable diseases (NCDs), nearly half of which are premature and apply to individuals of working age. Although such deaths are largely preventable, effective solutions continue to elude the public health community.
- One reason is the considerable influence of the “commercial determinants of health”: NCDs are the product of a system that includes powerful corporate actors, who are often involved in public health policymaking.
- This article shows how a complex systems perspective may be used to analyze the commercial determinants of NCDs, and it explains how this can help with (1) conceptualizing the problem of NCDs and (2) developing effective policy interventions.
Context
The high burden of noncommunicable diseases (NCDs) is politically salient and eminently preventable. However, effective solutions largely continue to elude the public health community. Two pressing issues heighten this challenge: the first is the public health community's narrow approach to addressing NCDs, and the second is the involvement of corporate actors in policymaking. While NCDs are often conceptualized in terms of individual‐level risk factors, we argue that they should be reframed as products of a complex system. This article explores the value of a systems approach to understanding NCDs as an emergent property of a complex system, with a focus on commercial actors.Methods
Drawing on Donella Meadows's systems thinking framework, this article examines how a systems perspective may be used to analyze the commercial determinants of NCDs and, specifically, how unhealthy commodity industries influence public health policy.Findings
Unhealthy commodity industries actively design and shape the NCD policy system, intervene at different levels of the system to gain agency over policy and politics, and legitimize their presence in public health policy decisions.Conclusions
It should be possible to apply the principles of systems thinking to other complex public health issues, not just NCDs. Such an approach should be tested and refined for other complex public health challenges. 相似文献98.
HOWARD S. CUCKLE NICHOLAS J. WALD KIRAN NANCHAHAL JAMES DENSEM 《BJOG : an international journal of obstetrics and gynaecology》1989,96(1):52-60
Summary. The risk of having a Down's syndrome term pregnancy was estimated using maternal age and the results of two maternal serum alpha-fetoprotein (AFP) tests carried out between 14 and 20 weeks gestation. The estimates of risk were derived from published data and the AFP results from nine affected and 145 unaffected pregnancies in which repeat testing had been carried out. Repeat AFP testing is unjustified in antenatal screening programmes for Down's syndrome, but if a second test happens to have been done, the appropriate estimate of risk that would be applicable when counselling individual patients depends on both results. For example a woman aged 35 years and 6 months with a first AFP level of 0–50 multiples of the normal median (MoM) was estimated to have a risk of 1:172. If a second test were done on a fresh sample and the AFP level were 0·80 MoM then the estimated risk would be 1:216 which is higher than the estimated risk of 1:353 obtained if the second test were regarded as the only result. Estimates of risk are given for maternal serum AFP results in first and second tests ranging from 0·40 to 2·50 MoM. 相似文献
99.
NICHOLAS M. FISK Foreman Fellow G. N. BRUCE STOREY Head 《BJOG : an international journal of obstetrics and gynaecology》1988,95(11):1137-1143
Summary. Obstetric cholestasis has been associated with a high incidence of stillbirth and perinatal complications. Between 1975 and 1984, 83 pregnancies were complicated by cholestasis. Meconium staining occurred in 45%, spontaneous preterm labour in 44%, and intrapartum fetal distress in 22%. Of 86 infants two were stillborn and one died soon after birth. Perinatal mortality fell from 107 in a previous series from this hospital (1965–1974) to 35/1000 in this series. Cardiotocography, estimations of oestriol, liver function tests and ultrasonic assessment of amniotic fluid volume failed to predict fetal compromise, whereas amniocentesis revealed meconium in 8 of 26 pregnancies. Early intervention was indicated in 49 pregnancies, 12 because of fetal compromise. This study suggests that intensive fetal surveillance, including amniocentesis for meconium, and induction of labour at term or with a mature lecithin/sphyngomyelin ratio, may reduce the stillbirth rate in this 'high-risk' condition. 相似文献
100.
W. F. GREEN N. R. NICHOLAS C. M. SALOME A. J. WOOLCOCK 《Clinical and experimental allergy》1989,19(2):203-207
Two studies were made to determine the acaricidal and allergen reducing properties of Allersearch DMS solution. In Study 1, samples of dust and carpet containing living mites were treated, in vitro, with DMS solution. No living mites were found in dust after 3-4 min or in carpets 50 min after treatment. In Study 2, mite counts and allergen estimation made on bed blankets before and after spraying with DMS solution showed a marked reduction in mite numbers (95%) and allergenicity (100-fold). Mite numbers and allergenicity stayed at this low level for 6 weeks. At 16 weeks both mites and allergens showed a slight increase, but were still significantly (P less than 0.001) below pretreatment levels. 相似文献