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1.
We have developed a resistance thermometry system for the acquisition, control and monitoring of temperature in large-scale cryogenic applications. The resistance of the sensor is converted to a voltage using a self-balancing AC bridge circuit featuring square-wave excitation currents down to 1 nA. The system is easily scalable and includes intelligent features to treat special situations such as magnet quenches different from normal operation.  相似文献   
2.
We analysed a well-characterized group of 83 patients (43 men, 40 women; mean age +/- SEM: 65.5 +/- 0.6 years at the 10-year examination) with non-insulin-dependent (Type 2) diabetes mellitus (NIDDM) and in 123 control subjects (56 men, 67 women; mean age +/- 0.9 years) retrospectively for the relationship of apolipoprotein E (apo E) genotypes (E2/3, E3/3 vs E3/4, E4/4) to the incidence of clinical macrovascular disease and its risk factors and the incidence of microvascular complications of diabetes during the first 10 years of NIDDM, as well as carotid intima-media thickness measured by B-mode ultrasound at the 10-year examination. In patients with NIDDM, apo E4 genotype showed no relationship to clinical events or carotid intima-media thickness. However, in the control subjects with apo E4, the incidence of non-fatal myocardial infarction during the follow-up was increased (apo E4 positivity: 17.1%; apo E4 negativity 5.1%; p = 0.035) and they had higher common carotid intima-media thickness than those with apo E2/3 or apo E3/3 (1.15 +/- 0.05 mm vs 1.01 +/- 0.03 mm, p = 0.008). Apo E genotype groups showed no relationship to microvascular complications of diabetes, although control subjects with apo E4 positivity showed a higher frequency of microalbuminuria than those lacking apo E4. We conclude that apo E4 was a marker of vascular disease and increased atherosclerosis in non-diabetic subjects, whereas in the diabetic patients these relationships were absent. It is likely that NIDDM per se influences the vascular risk so overwhelmingly that the effects of other risk factors are obscured.  相似文献   
3.
BACKGROUND: Ultrasonically activated shears (UAS) have been documented to be both safe and fast devices in laparoscopic surgery. We studied whether the use of UAS would have some advantage in thyroid surgery. METHODS: Thyroidectomies, performed by one senior endocrine surgeon between December 1996 and February 1997, were retrospectively matched, with patients operated on by the same surgeon using the conventional method. RESULTS: Six pairs of total thyroidectomies and one pair of lobectomies could be matched. Mean operating time was 100 minutes for the patients operated on with the UAS and 154 minutes for the patients operated on with the conventional method. The mean operating time with the UAS was thus on average 64.6% of the operation time with the conventional method, with a 95% confidence interval from 50.1% to 83.5% (t = 4.00, 6 df, P = 0.007). CONCLUSIONS: In this material the use of UAS reduced significantly operating time in thyroidectomies.  相似文献   
4.
Triacylglycerols of the seed oils rich in α- and/or γ-linolenic acid moieties were separated by silver-ion high-performance liquid chromatography (HPLC) followed by on-line atmospheric pressure chemical ionization-mass spectrometric (APCI-MS) detection. Mass spectra of most triacylglycerols exhibited abundant [M + H]+ and [M − RCO2]+ ions, which defined the molecular weight and the molecular association of fatty acyl residues of a triacylglycerol, respectively. Silver ions formed weaker complexes with triacylglycerols containing γ-linolenic acid than with those containing α-linolenic acid, i.e., the elution order of molecules wasXYT γ>XYT α’,XT γ T α>XT α T α>, andT γ T γ T γ>T γ T γ T α>T γ T α T α>T α T α T α, whereT α=α-linolenic acid,T γ=γ-linolenic acid, andX, Y=fatty acids different from linolenic acid. Furthermore, silver-ion HPLC resulted in partial separation within equally unsaturated triacylglycerols according to differences in the combined number of acyl carbons. Regioisomeric forms of triacylglycerols were not determined from the seed oil samples, although differences were measured with reference compounds in the relative abundances of [M − RCO2]+ ions formed by a loss of a fatty acyl residue from thesn-2 position and thesn-1/3 positions. Silverion HPLC/APCI-MS provided valuable information for structure elucidation of seed oil triacylglycerols: 43 molecular species were identified from cloudberry seed oil, 39 from evening primrose oil, 79 from borage oil, 44 from alpine currant, and 56 from black currant seed oils. The quantitation requires to be studied further, especially in those cases where several molecular weight species of triacylglycerols eluted in a single chromatographic peak.  相似文献   
5.
The measurement of the piston velocity of a hydraulic actuator   总被引:1,自引:0,他引:1  
The use of three types of transducers to measure the velocity of the piston shaft of a hydraulic actuator is investigated. The types of transducers are linear magnetic scale, magnetostrictive, and optical rotary encoder. Different methods of calculating the piston velocity from the position information are proposed, and the results of the test measurement are presented  相似文献   
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BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) are risk factors for peptic ulcer in rheumatoid arthritis (RA) patients, but the contribution of reactive gastritis, concomitant Helicobacter pylori infection, or RA activity to NSAID ulcer pathogenesis is unknown. METHODS: Ninety-six RA patients taking NSAIDs and dyspeptic sex- and age-matched control patients without NSAID use or an RA diagnosis were enrolled in the study. RESULTS: Gastric ulcer (GU) was detected in 29 (30%) RA patients and 3 control patients (P < 0.001). Sixteen RA patients and no control patient had an H. pylori-negative GU. The GUs of the RA patients were mainly located in the prepyloric region (28%) and antrum (62%). Nine of the 29 RA patients (31%) with GU had more than 1 ulcer. Erosive gastropathy was detected in 34 (71% H. pylori-negative) RA patients and in 13 (62% H. pylori-negative) control subjects (P < 0.001). Chronic gastritis was observed in 65 RA patients (48% H. pylori-negative) and in 58 control subjects (43% H. pylori-negative) (NS). whereas reactive gastritis was found in only 2 RA patients and in none of the controls. Corticosteroid use was the only independent risk factor for GU: odds ratio was 6.8 (95% confidence interval, 1.3-36.0). The prevalences of duodenal ulcer or esophagitis were not increased in RA patients. CONCLUSIONS: RA patients using NSAIDs continuously are at a greatly increased risk of developing both H. pylori-negative and -positive GUs, and corticosteroid use is an independent risk factor for ulcer development. Most RA patients have chronic gastritis, whereas reactive gastritis is rarely associated with continuous NSAID use in RA patients.  相似文献   
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9.
An empirical statistical model is described for the use of indoor radon monitoring data as an indicator of the areal radon risk from soil and bedrock. The percentages of future homes expected to have radon concentrations exceeding the design level of 200 Bq/m3 unless constructed to provide protection against the entry of radon were assessed. The radon prognosis was made for different subareas, soil types and foundation types. This kind of report is used by the health and building authorities. In this study, 2689 indoor radon measurements were made in one of Finland's most radon-prone areas, consisting of eleven municipalities with a total area of 4600 km2 and a population of 186,000. Radon concentrations were seasonally adjusted. Data on the location, geology and construction of buildings were determined from maps and questionnaires. The measurements covered different kinds of geological units in the area. The radon risk is highest in the gravel-dominated subarea in an ice-marginal formation and lowest in the northern half of the area in buildings constructed on bedrock. In these two areas, the design level of 200 Bq/m3 would be exceeded in 99% and 39% of new houses with slab-on-grade.  相似文献   
10.
The purpose of this article is to describe the developmental level of QA in Finland. Working unit, regional and national level QA activities are reflected. The major effort to study the current situation of nursing QA was taken by STAKES (The National Research and Development Centre for Welfare and Health) in the beginning of 1993. Over 1200 institutions received a questionnaires where their QA activities were inquired. The increasing need for multiprofessional cooperation, better information and participation of nursing care personnel are discussed. To utilize research findings and to increase resources and skills of nursing care personnel to perform small scale studies are seen essential for QA advancement. To receive good quality care is a right of all patients. The nursing care personnel is responsible to deliver that kind of care. QA is a means to provide it. Accountability is demanded by both public and profession itself. Nurses have taken the leadership in providing good quality nursing care.  相似文献   
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