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1.
OBJECTIVE: To assess whether hypertension is a risk factor for hysterectomy performed for benign diseases. METHODS: Self-report questionnaires were collected from 77% of 2301 Danish women aged 30, 40, 50, or 60 years selected at random in 1982 for a prevalence study. Information about cardiovascular diseases, hypertension, use of medicine, weight and dieting history, life-styles, psychologic factors, gynecologic history (including history of hysterectomy), and social background were recorded. Weight, height, and blood pressure were measured. In an incidence study, the cohort was followed during 1982-1990 via central registers to assess the incidence of hysterectomy. Logistic and Cox regressions were used to analyze data. RESULTS: In the prevalence study, history of hypertension partly explained the relation between hysterectomy and cardiovascular diseases. In the incidence study, history of hypertension and use of diuretics were significant risk factors for hysterectomy. After confounder control, use of diuretics was explained by weight-related variables, and hypertension was a risk factor for hysterectomy in educated women (adjusted relative risk [RR] 2.88, 95% confidence interval [CI] 1.07, 7.76) and in women with weight fluctuations (adjusted RR 3.31, 95% CI 1.35, 8.14). Weight cycling and lack of education remained significant risk factors for hysterectomy in women with and without hypertension, respectively. CONCLUSION: History of hypertension, weight cycling, and lack of education are closely related risk factors for premenopausal hysterectomy. These three risk factors contribute to women undergoing hysterectomy having an increased risk for cardiovascular diseases. We proposed that hypertension might be a plausible biological cause of menorrhagia and an indication for hysterectomy. 相似文献
2.
Yukihisa Tanaka Jiro Hirano Tadashi Funada 《Journal of the American Oil Chemists' Society》1992,69(12):1210-1214
In an attempt to concentrate the content of DHA (docosahexaenoic acid) in a glyceride mixture containing triglyceride, diglyceride
and monoglyceride, fish oil was hydrolyzed with six kinds of microbial lipase. After the hydrolysis, free fatty acid was removed
and fatty acid components of the glyceride mixtures were analyzed. When the hydrolysis withCandida cylindracea lipase was 70% complete, the DHA content in the glyceride mixture was three times more than that in the original fish oil.
The EPA (eicosapentaenoic acid) content became almost 70% of the original fish oil. Hydrolysis with other lipases did not
result in an increase in the DHA content in the glyceride mixtures. Hydrolysis of DHA-rich tuna oil (DHA content is about
25%) withCandida cylindracea lipase resulted in 53% DHA in the glyceride mixture. The EPA content, however, remained close to that of the original tuna
oil. In this report, the acyl chain specificity of lipases is evaluated in terms of hydrolysis resistant value (HRV). HRV
is the ratio between the DHA contents in the glyceride mixture of hydrolyzed oil and original oil. HRV clearly indicates differences
in hydrolysis between DHA and other fatty acids (e.g., saturated and monoenoic acids). 相似文献
3.
Hiroyuki Miki Takanori Takeno Toshiyuki Takagi Alexei Bozhko Mikhail Shupegin Hideya Onodera Takao Komiyama Takashi Aoyama 《Diamond and Related Materials》2006,15(11-12):1898
Superconductivity in a tungsten-containing carbon-oxide film was reported. The film with 500 nm thickness was deposited onto polycrystalline silicon oxides using chemical vapor deposition and the co-sputtering of a tungsten metal target. The bonding state of the carbon atoms and the macroscopic and microscopic crystal structure of the film were investigated by Raman spectroscopy, X-ray diffraction and transmission electron microscopy measurements. From the experimental results, we determined that this film essentially had an amorphous structure. The temperature dependence on resistivity was measured in the temperature range of 2–300 K. Resistive superconducting transition was observed at 3.8 K. The dc magnetizations were measured in the temperature range of 1.8–6.5 K. The diamagnetism resulting from a superconductive state was observed below 3.75 K, which is consistent with a resistive superconducting transition. It is thought that the finite sized clusters of the different superconductive transition temperatures cooperatively produce a macroscopic superconducting phenomenon. 相似文献
4.
A membrane, which has positively charged groups in the polymer main chain, was prepared from polyethylenimine by crosslinking and successive alkylation. Dibromoalkane was used as a crosslinking agent. The crosslinked membrane was alkylated using methyl iodide under several conditions. Elemental and ICP emission analyses were introduced to measure the rates of alkylation and quaternization. From the membrane potential measurement, the effective charge density was estimated. The highest value was about 1.0 M, which was obtained by a prolonged alkylation time. This value was larger than that of some commercial ion exchange membranes. The effective charge density, which was obtained by the last alkylation procedure, was 10 times larger than that of the former one, though the rate of quaternizing increased by less than a factor of two. This implies that the activity constant in the membrane increased when the charge density is increased. © 1993 John Wiley & Sons, Inc. 相似文献
5.
The change of the conductivity in the rare earth perovskite oxide took place after the chemisorption of flammable gases. The sensitivity for methanol was highest. From the conductivity change of these perovskite oxides after the injection of methanol, the energy needed to promote an electron from a conducting to a nonconducting state, E=E
c-E
t, could be derived from the equation=A
0 exp (–E/kT). LnCoO3 had the smallest E and H (metal-O), which is the binding energy of oxygen coordinating to the metal ions, but exhibited the highest activity for gas sensing. The gas sensing mechanism was also considered. 相似文献
6.
α,β,β-Trifluoroethylenesulfonyl fluoride (TFESF) was grafted onto polyethylene (PE) film by a simultaneous-irradiation method. The influences of the grafting conditions were analyzed kinetically. The dependencies of the grafting rate on the dose rates and monomer concentrations ranging from 10 to 75% were found to be of 1 and 0 order, respectively. The overall activation energy for the graft polymerization was 2.05 × 104 J/mol. The grafting rate was found to be independent of the film thicknesses ranging from 25 to 100 μm. 相似文献
7.
The catalytic effects of liquid metals for low-temperature (336 °C) asphalt-cracking have been examined using a semi-batch reactor. All the liquid metals examined (Bi, Cd, Ga, In, Pb and Sn) effectively catalysed the reduction of molecular weight with minimal gasification (<1 wt%). Gasification had a positive correlation with the reduction in molecular weight in the processed asphalts. The catalytic activities of liquid metals tor these two reactions were proportional to a parameter which represents the interaction between the atoms of the catalyst metal and the radicals formed in the course of the reaction. Mass flow among four fractions (saturates, aromatics, resins and asphaltenes) had two independent paths: conversion of resins to saturates and of aromatics to asphaltenes. The former path dominated when catalytic dehydrogenation activity was relatively low, whereas the latter dominated when the catalytic activity was high. 相似文献
8.
9.
Analysis of Energy Saving and Environmental Characteristics of Electric Vehicles in Regionally Disaggregated World Energy Model
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This paper investigates the impact of an extensive introduction of electric vehicles (EV) and plug‐in hybrid vehicles (PHEV) into the global energy system by 2050. The significant growth of automobile ownership in emerging countries is likely to increase world oil demand and the associated carbon dioxide emissions. In order to address these energy, security, and environmental concerns, the deployment of clean energy vehicles, such as EV and PHEV, is expected to play a crucial role due to their high fuel efficiency. Consequently, we develop both a global energy system model and a world vehicle penetration model, which can explicitly analyze the impact of EV introduction into the seasonal daily electric load curve, with consideration of the specific electricity charging profile through 2050. The simulation results confirm that EV deployment contributes to energy conservation, because oil demand reduction outstrips the growth in electricity demand and the associated fuel input into the power generation mix. Concerning carbon dioxide abatement, the magnitude of the impact relies on the carbon intensity of the power generation mix. If the intensity is low enough to guarantee a carbon mitigation effect due to EV fuel saving, emissions reduction is well assured. It should be noted, however, that in regions with high carbon intensity in the power generation mix, carbon emissions per mileage of EVs is almost equivalent to that of efficient gasoline vehicles such as hybrid vehicles, and the figure for PHEV is slightly higher than for hybrid vehicles. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 20–36, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22373 相似文献
10.
Jianming Zhu Dr. Jing Wang Kai Cheng Hui Chen Dr. Ran An Dr. Yaping Zhang Prof. Makoto Komiyama Prof. Xingguo Liang 《Chembiochem : a European journal of chemical biology》2020,21(6):785-788
High-resolution melting (HRM) analysis has been improved and applied for the first time to quantitative analysis of enzymatic reactions. By using the relative ratios of peak intensities of substrates and products, the quantitativity of conventional HRM analysis has been improved to allow detailed kinetic analysis. As an example, the ligation of sticky ends through the action of T4 DNA ligase has been kinetically analyzed, with comprehensive data on substrate specificity and other properties having been obtained. For the first time, the kinetic parameters (kobs and apparent Km) of sticky-end ligation were obtained for both fully matched and mismatched sticky ends. The effect of ATP concentration on sticky-end ligation was also investigated. The improved HRM method should also be applicable to versatile DNA-transforming enzymes, because the only requirement is that the products have Tm values different enough from the substrates. 相似文献