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131.
OE Kolesova LM Alekseeva LA Apollonova TM Frolova VV Ivanitskaia 《Canadian Metallurgical Quarterly》1982,45(2):59-62
The increase of the concentration of fatty acids, the reduction in the concentration of serotonin, the lowering of the activity of glucose-6-phosphate dehydrogenase and transketolase, and the development of compensated metabolic acidosis were discovered in the stage that preceded strophanthine arrhythmia. These characteristics may be recommended for a wider use on the clinical basis for predicting arrhythmias in the treatment of cardiac glycosides. 相似文献
132.
JL Wright LM Lawson PD Pare BJ Wiggs S Kennedy JC Hogg 《Canadian Metallurgical Quarterly》1983,127(4):474-477
To investigate the effect of smoking status on pulmonary function and pathologic changes in the peripheral airways, we studied 97 patients who underwent thoracotomy for coin lesions. The patients were divided into 4 groups: nonsmokers (n = 9), current smokers (n = 51), and those who had ceased smoking for less than (n = 18) or more than (n = 19) 2 yr prior to surgery. We found that current smokers had evidence of air-flow obstruction with abnormal lung volumes when compared with nonsmokers. Ex-smokers had lung volumes similar to those of nonsmokers, but showed evidence of obstruction, with the FEV1/FVC between the values found for nonsmokers and current smokers. Examination of the small airways showed that the membranous bronchioles of current smokers and ex-smokers displayed only increased goblet cell metaplasia when compared with those in nonsmokers; the respiratory bronchioles of current and ex-smokers showed increases in intraluminal and airway wall inflammatory cells, wall fibrosis, and pigment deposition. We conclude that patients who currently smoke cigarettes have reduced lung function that is associated with abnormalities of airway structure. Although those who have stopped smoking have function that is closer to the nonsmoking group, there is no apparent difference in structural change between current and ex-smokers. 相似文献
133.
The optical constants of water ice have been determined in the near infrared from 4000 to 7000 cm(-1). Polycrystalline ice films with thickness as great as ~1164 mum were formed by condensation of water vapor on a cold silicon substrate at temperatures of 166, 176, 186, and 196 K. The transmission of light through the ice films was measured during their growth from 0 to 1164 mum over the frequency range of approximately 500-7000 cm(-1). The optical constants were extracted by means of simultaneously fitting the calculated transmission spectra of films of varying thickness to their respective measured transmission spectra with an iterative Kramers-Kronig technique. Equations are presented to account for reflection losses at the interfaces when the sample is held in a cell. These equations are used to reanalyze the transmission spectrum of water ice (358-mum sample at 247 K) recorded by Ockman in 1957 [Philos. Mag. Suppl. 7, 199 (1958)]. Our imaginary indices for water ice are compared with those of Gosse et al. [Appl. Opt. 34, 6582 (1995)], Kou et al. [Appl. Opt. 32, 3531 (1993)], Grundy and Schmitt [J. Geophys. Res. 103, 25809 (1998)], and Warren [Appl. Opt. 23, 1206 (1984)], and with the new indices from Ockman's spectrum. The temperature dependence in the imaginary index of refraction observed by us between 166 and 196 K and that between our data at 196 K and the data of Gosse et al. at 250 K are compared with that predicted by the model of Grundy and Schmitt. On the basis of this comparison a linear interpolation of the imaginary indices of refraction between 196 and 250 K is proposed. We believe that the accuracy of this interpolation is better than 20%. 相似文献
134.
Xu Y. Tolbert L.M. Chiasson J.N. Campbell J.B. Peng F.Z. 《Electric Power Applications, IET》2007,1(6):853-861
A generalised instantaneous non-active power theory is presented. Comprehensive definitions of instantaneous active and non-active currents, as well as instantaneous, average and apparent powers, are proposed. These definitions have flexible forms that are applicable to different power systems, such as single-phase or multi-phase, periodic or non-periodic and balanced or unbalanced systems. By changing the averaging interval and the reference voltage, various non-active power theories can be derived from this theory. The definitions of instantaneous active and non- active currents provide an algorithm for a STATCOM to calculate the non-active current in the load current. The theory is implemented by the STATCOM, and four cases (three-phase balanced RL load, three-phase unbalanced RL load, diode rectifier load and single-phase load) are tested. The experimental results show that the STATCOM can perform instantaneous non-active power compensation, and both the fundamental non-active component and the harmonics are eliminated from the utility so that nearly unity power factor can be achieved. The STATCOM also has a fast dynamic response for transients. 相似文献
135.
OBJECTIVES: To identify the predictors of perceived health and predictors of changes in perceived health in frail hospitalized older persons during the year after hospitalization. DESIGN: Both cross-sectional and longitudinal multivariate analysis of data from a cohort followed for 1 year. SETTING: Six hospital in a group practice model health maintenance organization (HMO) in Southern California. PARTICIPANTS: A total of 1889 persons aged 65 or older who met at least one of 13 inclusionary criteria for a randomized trial of Comprehensive Geriatric Assessment consultation at admission and completed three Functional and Health Status Questionnaires (FHSQ) during a 12-month period. MEASUREMENTS: Functional and health status measures included basic and intermediate activities of daily living (BADL and IADI) and social activities (SA) scales from the Functional Status Questionnaire as well as the mental health index (MHI) and current health perception (CHP), scales from the Medical Outcomes Study short from. Subject's severity of disease was measured by the Resource Demand Scale (RD Scale). RESULTS: In the cross-sectional analyses, MHI score, IADL score, RD Scale, history of falls during the 3 months before hospitalization, and female gender were significant predictors of perceived health in all models for each time point, BADL score, age, presence of incontinence, and ethnicity were significant in the model for baseline only, and SA score was significant in models for 3 months and 12 months only. In the longitudinal analyses, the baseline CHP score and the changes in MHI, IADL, and BADL score predicted CHP change from 0 to 3 months and from 3 to 12 months. CONCLUSIONS: Functional and psychosocial health indicators are the most important and most consistent predictors of perceived health. Our study showed that several predictors of perceived health in cross-sectional analysis did not predict changes in perceived health over a 1-year period. Hence, to fully understand the medical and social contributors to perceived health, a comprehensive approach using both cross-sectional and longitudinal analyses is necessary. 相似文献
136.
Ratings of the performances of practicing internists by hospital-based registered nurses 总被引:1,自引:0,他引:1
PURPOSE: To examine the feasibility and reliability of ratings completed by hospital-based registered nurses of the humanistic qualities, communication skills, and selected aspects of the clinical skills of practicing internists. METHOD: In 1988-1989, registered nurses who worked in the same 175 hospitals as 232 internists with admitting privileges at these hospitals rated the internists' performances. The nurses were selected from medicine floors, specialty floors, and intensive care units and/or critical care units, using lists provided by head nurses. A total of 1,877 rating questionnaires with 13 performance categories were collected (with a mean of 8.01 nurses per internist). The ratings were analyzed to determine measurement characteristics and the relationships of the nurses' demographic characteristics to the ratings. In addition, for each of ten performance categories for 152 of the internists, the average rating each internist received from nurses was compared with the average rating each internist received from peer physicians. Statistical analysis used Pearson correlations, canonical correlations, factor analyses, Student's t-tests, analysis of variance, and stepwise multiple regression. Finally, the internists themselves, including physicians who were not actually rated by the nurses, were asked to complete a brief questionnaire that included questions about their opinions of the use of nurses' ratings. RESULTS: The nurses' ratings correlated moderately strongly with the peer physicians' ratings and had a common structure. However, the nurses' ratings were lower for several humanistic qualities, including respect, integrity, and responsibility, and their ratings were higher for medical knowledge and verbal communications. Across the 13 performance categories, approximately 10-15 ratings from nurses were needed to obtain a reliable assessment of an internist's humanistic qualities and communication skills. Many internists felt that nurses' ratings should be used equally with, or at least as a lesser contribution to, ratings by peer physicians of humanistic qualities and communication skills. CONCLUSION: Nurses' ratings appear to provide a feasible and reliable method of evaluating the internists' communication skills and humanistic qualities, when used in conjunction with ratings by peer physicians. 相似文献
137.
N Zini AM Martelli LM Neri A Bavelloni P Sabatelli S Santi NM Maraldi 《Canadian Metallurgical Quarterly》1995,103(6):447-457
The complex pathway which links the agonist-cell membrane receptor binding to the response at the genome level involves, among other elements, protein kinase C (PKC). Agonists acting at the cell membrane can affect an autonomous nuclear polyphosphoinositide signaling system inducing an activation of nuclear phosphoinositidase activity and a subsequent translocation of PKC to the nuclear region. The fine localization of PKC has been investigated by means of electron microscopy quantitative immunogold labeling in 3T3 mouse fibroblasts, mitogenically stimulated by IGF-I. The enzyme, which in untreated cells is present in the cytoplasm, except for the organelles, and in the nucleoplasm, after IGF-I treatment is reduced in the cytoplasm and almost doubled in the nucleus. The PKC isoform translocated to the nucleus is the alpha isozyme, which is found not only associated with the nuclear envelope but mainly with the interchromatin domains. By using in situ matrix preparations, PKC appears to be retained at the nuclear matrix level, both at the nuclear lamina and at the inner nuclear matrix, suggesting a direct involvement in the phosphorylation of nuclear proteins which are responsible for the regulation of DNA replication. 相似文献
138.
GR Douglas J Jiao JD Gingerich LM Soper JA Gossen 《Canadian Metallurgical Quarterly》1996,28(4):317-324
In order to help establish criteria for optimizing protocols for in vivo mutation studies, lacZ transgenic mice (Muta mouse) were treated with five consecutive daily doses of ethylnitrosourea (50 mg/kg), sampled at times up to 55 days after treatment, and mutant frequencies and DNA sequences determined for liver and bone marrow. In the bone marrow, the mutant frequency rose very rapidly in the first 5 days after treatment to 34 times the control frequency. Subsequently, there was a brood peak where the mutant frequency did not vary significantly, although it did appear to begin to decline after 45 days. In contrast, in the liver, the peak mutant frequency (11 times the control frequency) was not achieved until 35 days, after which there appeared to be a slow decline up to 55 days, which was not statistically significant. Once the maximum mutant frequency was reached, the mutation spectra in the two tissues were indistinguishable. In contrast to the G:C-->A:T transitions in 5'-CpG sites characteristic of untreated mice, A:T-->T:A transversions and A:T-->G:C transitions were prominent in both liver and bone marrow of ENU-treated mice, suggesting the involvement of unrepaired O2- and O4-ethylthymine adducts. In addition, G:C-->T:A transversions were induced in liver. This study demonstrates the possibility that although tissues may have different mutation fixation times, a single mutation fixation time equal to the longest time may be appropriate for in vivo mutation studies, provided that the mutation frequency does not decline appreciably after the peak is reached. This study also illustrates the necessity of ensuring that mutation characteristics are determined after optimal fixation has occurred. 相似文献
139.
RA Reinhardt MP Masada GK Johnson LM DuBois GJ Seymour AC Allison 《Canadian Metallurgical Quarterly》1993,20(7):514-519
Interleukin (IL)-1 alpha and beta are cytokines which can mediate inflammatory, bone resorbing, and reparative effects in the periodontium, but few longitudinal data exist exploring their role following periodontal therapy. This study examined gingival crevicular fluid (GCF) concentrations of IL-1 alpha and IL-1 beta at sites with shallow sulci (SS) or inflamed moderate/advanced pockets (M/AP) before and 6 months after treatment with closed scaling/root planing (SC/RP) or papillary flap debridement (PFD), all in the same subject (n = 14 patients). No significant differences were noted in IL-1 alpha or beta concentrations (determined with two-site enzyme-linked immunosorbent assays) between SS and M/AP sites at baseline. While both therapies improved clinical parameters of periodontal disease, IL-1 alpha concentration increased significantly (p < 0.05) in M/AP-PFD sites 6 months after treatment, but were unchanged in other groups. IL-1 beta concentrations were numerically lower after therapy, except for a significant increase (p < 0.05) in M/AP-PFD sites. These data suggest that surgical wound healing in an inflamed, plaque-infected site (M/AP-PFD) results in prolonged production of IL-1, which may be a reflection of the extent of tissue trauma and delayed wound healing. In spite of increased IL-1 levels, these sites demonstrated significant short-term improvement in clinical attachment level (+ 1.8 mm, p < or = 0.001) postoperatively. 相似文献
140.
A case of a 65-year old female patient is reported, dealing with consumption coagulopathy and secondary hyperfibrinolysis due to cystic spleen. Following treatment with heparin, antifibrinolytic agents and replacement of clotting factors prior to surgery, the patient attained a satisfactory condition to be operated on. After removal of the cystic spleen, which was interspersed with massive hemorrhages, blood coagulation returned to normal quickly and continuously. The pathogenesis of consumption coagulopathy in relation to cystic spleen is discussed and it is referred to the pathomechanism of similar blood disorders in hemangiomatous and cavernous lesions of Kasabach-Merritt-syndrome, Klippel-Trenaunay-syndrome and pachymeningeosis haemorrhagica interna. 相似文献