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11.
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
12.
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
13.
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
14.
Oleshko V. I. Tarasenko V. F. Burachenko A. G. Nguyen V. V. 《Technical Physics Letters》2019,45(4):309-313
Technical Physics Letters - In this paper, we experimentally studied pulsed electron beams with a high local density. The conditions in which the energy density cumulation is observed during the... 相似文献
15.
K Rithidech VP Bond EP Cronkite MH Thompson JE Bullis 《Canadian Metallurgical Quarterly》1995,92(4):1152-1156
In an effort to identify the precise role of a deletion at regions D-E of mouse chromosome 2 [del2(D-E)] during the development of radiation-induced myeloid leukemia, we conducted a serial sacrifice study in which metaphase chromosomes were examined by the G-banding technique. Such metaphase cells were collected from x-irradiated mice during the period of transformation of some of the normal hematopoietic cells to the fully developed leukemic phenotype. A group of 250 CBA/Ca male mice (10-12 weeks old) were exposed to a single dose of 2 Gy of 250-kilovolt-peak x-rays; 42 age-matched male mice served as controls. Groups of randomly selected mice were sacrificed at 20 hr, 1 week, and then at intervals of 3 months up to 24 months after x-irradiation. Slides for cytogenetic, hematological, and histological examination were prepared for each animal at each sacrifice time. An expansion of cells with lesions on one copy of chromosome 2 was evident in 20-25% of treated mice at each sacrifice time. The majority of such lesions were translocations at 2F or 2H, strongly suggesting hypermutability of these sites on mouse chromosome 2. No lesions were found in control mice. The finding leads to the possibility that genomic lesions close to 2D and 2E are aberrants associated with radiation leukemogenesis, whereas a single clone of cells with a del2(D-E) may lead directly to overt leukemia. The data also indicate that leukemic transformation arises from the cumulative effects of multiple genetic events on chromosome 2, reinforcing the thesis that multiple steps of mutation occur in the pathogenesis of cancer. 相似文献
16.
Bovine leukocyte adhesion deficiency--clinical course and laboratory findings in eight affected animals 总被引:1,自引:0,他引:1
KE Müller WE Bernadina HC Kalsbeek A Hoek VP Rutten GH Wentink 《Canadian Metallurgical Quarterly》1994,16(2):65-71
To compare multiple and singleton pregnancies in the treatment of threatened preterm delivery with prolonged intravenous ritodrine, 32 women with multiple pregnancy (26 twins, 6 triplets, 70 fetuses, 30.3 +/- 3.5 weeks) and 51 women with singleton pregnancy (31.3 +/- 2.6 weeks) admitted for threatened preterm delivery without rupture of the membranes were the subjects of a retrospective study of obstetric data, perinatal outcome and maternal adverse effects. Significance was assessed by chi 2 test and Student's t test. Multiple pregnancies were associated with a marked increase in the duration of tocolysis (17.2 +/- 17.3 vs. 7.6 +/- 8.1 days, P < 0.01), incidence of delivery before 37 weeks (87.5 vs. 35.3%, P < 0.01) and incidence of maternal cardiovascular complications (34.4 vs. 4.0%, P < 0.01), including three cases of pulmonary edema. The incidences of delivery before 32 weeks (12.5 vs. 7.8%) and of neonatal death (2.9 vs. 0%) were not significantly different in the two groups. Multiple pregnancies dramatically increased the incidence of maternal adverse effects of prolonged intravenous ritodrine therapy. Neonatal benefit is questionable and was difficult to establish since it was not a randomized study. 相似文献
17.
NS Ponomareva OG Voskresenskaia AA Kamenski? VP Golubovich IP Ashmarin 《Canadian Metallurgical Quarterly》1998,48(3):471-477
Ethinylestradiol (EE) has evident paradoxical effects on cancer risk for human breast and hepatic cancer which parallel in some respects its effects on estrogen-induced neoplasms in the hamster kidney and liver. EE has been shown to be only weakly carcinogenic in the hamster kidney, but the most potent carcinogenic estrogen in the hamster liver following prolonged treatment. Unexpectedly, when EE and potent carcinogenic estrogens, such as diethylstilbestrol (DES), 17beta-estradiol (E2) and Moxestrol (MOX), are administered concomitantly, estrogen-induced carcinogenesis in the kidney is completely prevented. In studying this novel finding, we found that, compared with E2 exposure alone, EE at 0.05 and 1.0 nM significantly (P < 0.001) inhibited the rise in proliferation of cultured primary hamster proximal renal tubular (PRT) cells in the presence of E2 (1.0 nM). Consistent with these findings, combined EE + DES treatment for 5.0 months reduced hamster kidney c-myc, c-fos and c-jun RNA expression to 43, 37 and 52%, respectively, compared with levels observed after DES treatment alone. Interestingly, TAM + DES treatment for the same period also resulted in the same low level of RNA expression of these proto-oncogenes. c-MYC, c-FOS and c-JUN protein products were comparably reduced after either EE + DES or TAM + DES treatment. It appears that c-fos expression and c-FOS protein levels in the hamster kidney were more responsive to TAM inhibition. These data demonstrate that EE possesses unique anti-tumorigenic properties in vivo in the hamster kidney. Additionally, the observed anti-estrogen-like effect of EE on cell proliferation of cultured PRT cells suggests that EE may interfere critically with estrogen receptor (ER)-mediated mitogenic pathway(s) affected by potent carcinogenic estrogens, thus preventing subsequent gene dysregulation and, hence, tumor development. Based on competition studies, the differential binding of EE to hamster kidney ER relative to that of the other estrogens (E2, DES, MOX) appears not to contribute to the prevention of estrogen carcinogenesis at this organ site by EE. 相似文献
18.
NM Nasybullina VP Zherdev VI Gunar VM Kopelevich GS Kozlova 《Canadian Metallurgical Quarterly》1997,60(6):52-54
The authors studied the permeability of the blood-brain barrier (CEB) to two nootropics: calcium ketogomopantothenate (KRA-Ca), a GABA derivative, and and calcium salt of oxybutyrate (OB-Ca), a derivative of GOBA. It was established that both preparations penetrate the CEB easily and are found in the brain at different intervals after their administration. However, essential differences in the distribution constant of these drugs were disclosed: KPA-Ca permeated the CEB more intensively and was accumulated in larger amounts in the late-term intervals. 相似文献
19.
As the data collected in a survey we conducted show, a major part of the modern general practitioner's work continues to be in the field of family medicine. This fact is also confirmed by the results of other surveys of general practice today. Patients still appreciate their GPs as a source of good medical care and counseling for the whole family. Our own study has shown that most patients would even like to see an expansion of the GP's counseling activities. The duration of the doctor-family relationship extends over many years, and is frequently longer than a decade. 相似文献
20.
NA Tamarina WD McMillan VP Shively WH Pearce 《Canadian Metallurgical Quarterly》1997,122(2):264-71; discussion 271-2
BACKGROUND: Abdominal aortic aneurysms (AAAs) are characterized by degradation of collagen and elastin resulting from increases in matrix metalloproteinase (MMP) activity. Previous authors have identified isolated increases in expression of specific MMPs in AAAs, but none have compared relative levels of expression of particular MMPs to one another or to those of their inhibitors, the tissue inhibitors of metalloproteinases (TIMPs). This study proposes to quantify relative mRNA levels for interstitial collagenase (MMP-1), 72 kd type IV collagenase (MMP-2), 92 kd type IV collagenase (MMP-9), TIMP-1, and TIMP-2 in normal aorta (NA) and AAA to provide insight as to the relative importance of each in aneurysm formation. METHODS: Competitive polymerase chain reactions (PCRs) with gene-specific external standards and cDNA derived from AAAs (n = 8; mean age, 67.4 years) and NA (n = 5; mean age, 40.6 years) were used to quantify mRNA levels. Results were normalized to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA levels, determined by means of competitive PCR, and compared by means of Mann-Whitney statistics. RESULTS: Significant increases in MMP mRNA expression in AAA over NA were observed for MMP-1 (3.64 versus 0.3, p = 0.007), MMP-9 (78.03 versus 3.35, p = 0.003), TIMP-1 (835.32 versus 477.2, p = 0.027), and TIMP-2 (18.09 versus 4.14, p = 0.003). The ratio of MMP to TIMP mRNA levels was higher in AAA than NA (0.135 versus 0.045, p = 0.018). CONCLUSIONS: Increases in expression of MMP-1, MMP-9, and MMP/TIMP ratios may result in increased proteolysis and matrix degradation, which characterize AAAs. MMP-9 appears to be the predominant metalloproteinase expressed in AAA, because its mRNA levels were more than 20 times and 2 times higher than those of MMP-1 and MMP-2, respectively. TIMP-1 mRNA levels were in molar excess to those of any of the metalloproteinases studied. 相似文献