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11.
J Knodel VP Ruffolo P Ratanalangkarn K Wongboonsin 《Canadian Metallurgical Quarterly》1996,27(6):307-318
Two large national surveys in 1988 and 1933 provide new evidence on trends in family-size preferences in Thailand at a time when the Thai fertility transition is reaching its conclusion. Although the average preferred number of children has continued to decline, a resistant lower bound of two children is found for the vast majority of respondents, stemming, apparently, from a pervasive, although not inflexible, desire to have one child of each sex. Moreover, new evidence from birth-registration data indicates that the decline in the total fertility rate appears to have leveled off at about replacement level. These findings challenge the view that fertility in Thailand will continue to fall well below replacement level, and contradict recently expressed alarmist predictions of population decline in the foreseeable future. 相似文献
12.
OBJECTIVES: The Physician Orders for Life-Sustaining Treatment (POLST), a comprehensive, one-page order form, was developed to convey preferences for life-sustaining treatments during transfer from one care site to another. This study examined the extent to which the POLST form ensured that nursing home residents' wishes were honored for Do Not Resuscitate (DNR) and requests for transfer only if comfort measures fail. DESIGN: The study used chart record data to follow prospectively a sample of nursing home residents with the POLST. SETTING: Eight geographically diverse, long-term, adult-care facilities in Oregon in which the POLST was in use. PARTICIPANTS: Nursing home residents (n = 180), who had a POLST recording DNR designation and who indicated a desire for transfer only if comfort measures failed, were followed for 1 year. MEASUREMENTS: For all subjects: treatment and disposition after significant health status changes; orders for narcotics and for provision or limitation of aggressive interventions. For hospitalized subjects: diagnosis, medical interventions, and DNR orders. For those who died: cause and location of death, life-sustaining treatments attempted, and comfort measures provided. RESULTS: No study subject received CPR, ICU care, or ventilator support, and only 2% were hospitalized to extend life. Of the 38 subjects who died during the study year, 63% had an order for narcotics, and only two (5%) died in an acute care hospital. A total of 24 subjects (13%) were hospitalized during the year. Hospitalized subjects' mean length of stay was 4.9 days, and the mean rate of hospitalizations for all subjects was 174 per 1000 resident years. In 85% of all hospitalizations, patients were transferred because the nursing home could not control suffering. In 15% of hospitalizations (n = 4), the transfer was to extend life, overriding POLST orders. CONCLUSIONS: POLST orders regarding CPR in nursing home residents in this study were universally respected. Study subjects received remarkably high levels of comfort care and low rates of transfer for aggressive life-extending treatments. 相似文献
13.
TV Martyniuk IE Chazova VP Masenko VN Volkov IuN Belenkov 《Canadian Metallurgical Quarterly》1998,70(4):33-36
AIM: Assessment of RAAS and vasopressin in patients with primary pulmonary hypertension (PPH). MATERIALS AND METHODS: Activity of plasma renin (APR), angiotensin-converting enzyme (ACE), plasma levels of angiotensin II (AII) and vasopressin (VP), serum concentration of aldosteron (AS) were measured by radioimmunoassay and enzyme immunoassay in 21 PPH patients with circulatory failure (age 34.7 +/- 2.1 years), 11 patients with NYHA functional class II-III, 10 with class IV, and 10 control subjects (age 29.8 +/- 1.5 years). RESULTS: Compared to controls, 21 PPH patients had elevated RAAS parameters: APR up to 3.52 ng/ml/h (p < 0.05), activity of ACE up to 43.13 units, AII level up to 33.93 ng/ml (p < 0.01), AS up to 468.86 ng/ml (p < 0.01), VP up to 5.26 ng/ml (p < 0.001). Circulatory failure progression resulted in activation of all the RAAS components. This and VP activation was the greatest in PPH patients with ACE > 5 ng/ml/h. PPH patients with mean pressure in the pulmonary artery higher than 60 mm Hg demonstrated higher ARP, AS, VP, AII, ACE than those who had this pressure under 60 mm Hg. CONCLUSION: PPH patients display a noticeable activation of RAAS and VP. This activation seems to be secondary as the changes increase with elevation of the pressure in the pulmonary artery and aggravation of circulatory insufficiency. Plasma renin activity determines the degree of RAAS activation as a whole. The discovered activation of RAAS in PPH gives grounds for doubts in the validity of using ACE inhibitors in the treatment of PPH. 相似文献
14.
VI Korol''kov VP Krotov V Konvertino P Le?tem EV Trambovetski? J Fanton R Krisman IuV Gordeev D Evert AM Nosovski? J Konnolli 《Canadian Metallurgical Quarterly》1998,32(3):30-37
Medical practice guidelines are being developed rapidly and advocated as a crucial component in transforming and improving the delivery of health care services. However, little is known about the ability of hospitals to institute guidelines outside of experimental settings. This article approaches guideline implementation from the viewpoint of process innovation assimilation and presents specific recommendations for organizational tactics leading to successful implementation of practice guidelines. 相似文献
15.
L. P. Fominskii V. P. Tarabrina M. V. Levchuk 《Powder Metallurgy and Metal Ceramics》1985,24(10):745-750
Conclusions The electroerosion disintegration of a manganese-containing Sormait type alloy in water yields powders of spherical particle shape. A coarse (>40-m) fraction of such a powder consists mainly of hollow particles, which are the most suitable for the flame-spray deposition of coatings. The particles of the powder have a homogeneous fine-grained structure differing radically from that of the starting alloy, and surpass the latter in microhardness. The powder is passivated by Fe3O4 films which increase its resistance to attack by corrosive environments. EE powders may find application for the deposition of protective coatings.A group of Fe-base C-Mn-Si-Cr-Ni hard-facing alloys-Publisher.Translated from Poroshkovaya Metallurgiya, No. 10(274), pp. 66–71, October, 1985. 相似文献
16.
Strength of Materials - In view of the problem complexity, numerical methods, mainly finite and boundary element methods, are fairly widely used in the calculation of the static deformation of... 相似文献
17.
18.
K. I. Patrylak F. M. Bobonych Yu. G. Voloshyna M. M. Levchuk V. M. Solomakha L. K. Patrylak I. A. Manza O. M. Taranookha 《Catalysis Today》2001,65(2-4):129-135
A range of Pd-containing catalysts on the basis of mordenite–clinoptilolite rocks of different starting phase compositions is synthesized. Final phase composition and acidity of rocks change as the conditions of their dealumination are changed. The efficiency of catalysts synthesized is weakly influenced by change of mordenite component contents within 50–80%, and it is not inferior to the efficiency of the catalysts on the synthetic mordenite basis. The nature of active sites as trifunction ones and isomerization mechanism are proposed. 相似文献
19.
P Mooney M Sarmiento JM Bishop N Biswas NM Cason L Dauwe J Godfrey VP Kenney R Pemper E Rojek RC Ruchti WD Shephard G Ginther RM Edelstein CP Forsyth K Gamarnik AE Kreymer RJ Lipton JM McQuade DM Potter JS Russ L Spiegel DE Johnson D Buchholz LM Cremaldi SW Delchamps HS Mao JL Rosen W Sakumoto RA Schluter SB Sontz C Winter 《Canadian Metallurgical Quarterly》1989,39(9):2494-2498
20.
VP Costa S Kuzniec LJ Molnar GG Cerri P Puech-Le?o CA Carvalho 《Canadian Metallurgical Quarterly》1998,105(4):689-693
OBJECTIVE: This study aimed to evaluate the retrobulbar circulatory effects of reversed ophthalmic artery flow (ROAF) on the ophthalmic artery branches by means of color Doppler imaging. DESIGN: The design was a case-controlled study. PARTICIPANTS: Among 56 consecutive patients with severe (>70% stenosis) occlusive carotid artery disease, 15 patients (26.8%) with ROAF were identified. The control group consisted of 15 patients with similar degrees of carotid artery stenosis and forward ophthalmic artery flow. INTERVENTION: Arteriography and measurement of the retrobulbar hemodynamic parameters with color Doppler imaging were performed. MAIN OUTCOME MEASURES: Blood flow velocities and resistive index in the ophthalmic, central retinal, and temporal short posterior ciliary arteries were measured. RESULTS: Arteriography confirmed the diagnosis of ROAF in all 15 patients. There was no patient with ROAF diagnosed by arteriography and not diagnosed by color Doppler imaging. The frequency of bilateral severe occlusive carotid artery disease was significantly higher in the ROAF group (40%) compared to the control group (6.6%) (P = 0.04). Patients with ROAF showed significantly reduced vascular resistance in the ophthalmic artery (P = 0.03), higher vascular resistance, and lower blood flow velocities in the central retinal and temporal short posterior ciliary arteries (P < 0.05). CONCLUSION: This study suggests that patients with ROAF show a steal phenomenon, characterized by a shunt to the low-resistance intracranial circuit and reduction of retrobulbar blood flow. 相似文献