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991.
JK Bultema 《Canadian Metallurgical Quarterly》1994,32(2):19-24
1. With an inpatient suicide, the staff may experience grief for a variety of reasons. The staff member's perception of self as a competent mental health care provider may be destroyed. The caregiver may grieve the loss of an ideal. Some inpatient staff members mistakenly believe that suicide can always be prevented and that the multidisciplinary team can accurately assess all patients. 2. To successfully mourn a loss, Worden (1982) identified four tasks of grieving that must be completed: accept the reality of the loss; experience the pain of grief; adjust to an environment in which the deceased or lost object is missing; and withdraw emotional energy and reinvest it in another relationship. 3. Interventions to promote healing post-inpatient suicide must be aimed at individual caregivers and the multidisciplinary team. Individual caregivers will differ in their responses based on experiences, beliefs, values, and culture. 相似文献
992.
An increasing number of clinical trials have demonstrated that obese patients are more likely than lean individuals to be hypertensive. Moreover, both obesity and arterial hypertension have been identified as independent risk factors for cardiovascular disease. Pathophysiologically, obesity appears to have a major influence on the hemodynamic changes associated with hypertension. The available evidence suggests that at any given level of arterial pressure, obese hypertensive patients have a higher cardiac output and lower total peripheral resistance than do lean patients. Recent reports have indicated that obesity exerts a disparate effect on target organs in hypertension. Whereas at rest obesity seems to mitigate cardiovascular changes in the systemic vascular bed caused by hypertension, no such mitigation was observed in the renovasculature; left ventricular hypertrophy as a major cardiovascular risk factor was even exacerbated by the presence of obesity. The different hemodynamic patterns in obese hypertensive patients have recently been shown clinically relevant for treating hypertensive patients. 相似文献
993.
This study evaluated impedance cardiography (ZCG) estimates of stroke volume (SV) during exercise. Seven subjects were studied at rest and during progressive cycle exercise in supine and upright positions. SV was determined by ZCG (SVZCG) during exercise and for the first 5 cardiac cycles following exercise. SVZCG was compared with separate measurements of SV by CO2 rebreathing (SVCO2). Static blood resistivity (p) was measured at each level of exercise. No significant differences were found between supine exercise and immediate post-exercise values for the peak of the first derivative of the impedance change (dZ/dtmax), left ventricular ejection time (LVET), or SVZCG. Small differences in dZ/dtmax and SVZCG, but not LVET, were found in exercise to post-exercise cycling in the upright position. Intra-individual SVZCG and SVCO2 were moderately correlated (upright mean r = 0.64, supine r = 0.42) from rest to 70% of peak VO2. Similar correlations were found between Pulse-O2 (VO2/heart rate, used as an index to SV) and both SVZCG (upright r = 0.73, supine r = 0.57) and SVCO2 (upright r = 0.8, supine r = 0.65). The ZCG parameters dZ/dtmax and LVET correlated better with Pulse-O2 (dZ/dtmax: upright r = 0.92, supine r = 0.73; LVET: upright r = -0.9, supine r = -0.9). SVZCG calculated with the Kubicek equation performed as well as SVCO2. ZCG might be a superior method if the inversely correlated parameters, dZ/dtmax and LVET, were not expressed as a product to calculate SV. 相似文献
994.
The 3Y1 cell line, established from a rat whole embryo, is widely used as a normal immortalized fibroblast. We analyzed p53 mutations in four clonal lines derived from the 3Y1 cell line; 3Y1-B clone 1-6, 3Y1-C and two clonal lines (3Y1 cl-3 and 3Y1 cl-6) which had been transformed by the human papilloma virus E6 gene. Polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis and DNA sequencing showed that three clonal lines had a double mutation at codons 130 and 136 on the same allele and that the other clonal line, 3Y1 cl-3, had no mutations. 3Y1-B clone 1-6, which has been registered as the standard clonal line at the Japanese Cancer Research Resources Bank, demonstrated weak bands of the wild type allele, suggesting the existence of heterogeneous cell types in this "clonal" line. PCR-SSCP analysis of 25 subclones obtained by limiting dilution of 3Y1-B clone 1-6 cells revealed a mixture of two types of cells; 12 subclones showed only the bands of mutated allele, and 13 subclones showed both bands of the wild and mutated p53 alleles. These findings should be taken into consideration when using this cell line as a normal immortalized cell line. 相似文献
995.
SC Connor JR Everett KR Jennings JK Nicholson G Woodnutt 《Canadian Metallurgical Quarterly》1994,46(2):128-134
High resolution proton nuclear magnetic resonance (1H NMR) spectroscopy has been used to investigate the metabolism and urinary excretion of the aminopenicillins, ampicillin and amoxycillin, in rats and of amoxycillin in man. 1H NMR resonances of the aminopenicillins, together with those for their 5R, 6R and 5S, 6R penicilloic acids and diketopiperazine metabolites were detected, assigned and quantified in urine samples with the aid of spin-echo NMR techniques. The dimer of amoxycillin was detected in rat urine for the first time together with novel drug-related resonances assigned to amoxycillin carbamate. Quantitative 1H NMR spectroscopic results were consistent with HPLC and microbiological data considering that only single measurements were recorded. Due to the short analysis time and simple sample preparation, NMR was particularly useful for studying the metabolism of the aminopenicillins for which sample degradation poses analytical problems. The non-invasive character of 1H NMR spectroscopic analysis of urine also provided unique information on a reversible reaction between amoxycillin and bicarbonate, an endogenous urinary metabolite. 相似文献
996.
The widespread utilization of frontalis electromyographic feedback as a general relaxation strategy far preceded empirical evidence demonstrating its efficacy for this purpose. This article reviews parametric studies testing the association between frontalis reduction and concomitant EMG decreases in nontargeted muscle groups. The current research supports the contention that biofeedback reinforces discriminative responding to a specific muscle group and not generalized relaxation to adjacent muscle groups. Methodological problems are noted, and implications for future research are addressed. 相似文献
997.
70 university students who planned to enter graduate school in the helping professions viewed 1 of 4 videotapes. Two tapes described some of the relationships between the law and psychology, and 2 described the issues of sex bias and sex-role stereotyping in counseling women. The same male and female made identical presentations on each topic. Ss evaluated the presenter on a general measure of professional effectiveness and rated the importance of the tape's content. Three of the 4 hypotheses advanced were supported: (a) the male presenter received higher ratings than the female presenter, (b) the difference in ratings between the female and male presenters was greater for the topic directly related to women than for the topic not directly related, and (c) the female presenter discussing sex-role stereotyping received the lowest ratings of the 4 conditions. Contrary to predictions, topics were not rated as more important when presented by a male than by a female. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
This study investigates 2 patterns of maternal behavior typical of mammals, using a heteropteran insect as the study animal. Sehirus cinctus, a burrower bug (Heteroptera: Cydnidae), exhibits relatively well-developed maternal behavior that includes guarding eggs and provisioning offspring. Mothers remained maternally responsive to stimulus eggs for 24-48 hr following removal of their own eggs, but the response grew weaker with longer separation times. A proportion of nulliparous females also exhibited maternal responsiveness when presented with stimulus eggs. Males, however, never responded parentally to eggs. The results of this study highlight similarities in general female responsiveness to stimulus young and differences in male responsiveness to stimulus young among certain invertebrates and vertebrates. 相似文献
999.
JG Drougas SE Barnard JK Wright M Sika RR Lopez KA Stokes PE Williams CW Pinson 《Canadian Metallurgical Quarterly》1996,46(6):648-655
To our knowledge postoperative hepatic hemodynamics and hepatic metabolism have not been fully studied on a long-term basis. Our goal was to develop a large animal model that would permit the measurement of hepatic blood flow (BF), perihepatic pressures (P), and hepatic metabolism in a long-term setting. Catheters were inserted into the jugular vein, carotid artery, pulmonary artery, hepatic vein, and portal vein (PV) of 27 commercially bred pigs; ultrasonic transit time flowmeter probes were placed around the hepatic artery and PV. Daily postoperative measurements of jugular vein P, carotid artery P, pulmonary artery P, hepatic vein P, and PVP, as well as hepatic artery BF and PVBF, were recorded for 20 days. Hepatic carbohydrate metabolism was assessed by arteriovenous difference techniques. Jugular vein P, pulmonary artery P, hepatic vein P, PVP, and heart rate reached steady-state values during the first week, with a mean +/- SEM of 1.0 +/- 0.3 mm Hg for jugular vein P, 21.4 +/- 2.1 mm Hg for pulmonary artery P, 4.3 +/- 0.4 mm Hg for HVP, 7.8 +/- 0.5 mm Hg for PVP, and 116 +/- 4 beats per minute for heart rate. Mean carotid artery P increased from 65 +/- 3 mm Hg during surgery to 94 +/- 2 mm Hg on postoperative day 1 (P < 0.001) and to a mean 101 +/- 2 mm Hg thereafter. Total hepatic BF reached a steady-state value of 1,132 +/- 187 ml/min by postoperative day 7 (P = 0.19). Over week 1 hepatic artery BF measured as a percentage of total hepatic BF decreased from 35.0 +/- 3.0% to 15.5 +/- 2.7%, and PVBF increased from 65.0 +/- 3.0% to 84.5 +/- 2.7% (P < 0.005); both variables were steady thereafter. In the hemodynamic steady state the net hepatic balances of glucose, lactate, glycerol, and alanine in 5 pigs were 9.9 +/- 4.0, -4.2 +/- 0.4, -2.3 +/- 1.1, and -0.68 +/- 0.22 micromol/kg per min respectively. The net gut (portal-drained viscera) balances of glucose, lactate, alanine, and glycerol were -2.0 +/- 2.5, 1.1 +/- 0.5, 0.73 +/- 0.18, and -0.69 +/- 0.19 micromol/kg per min respectively. Thus, a reliable large animal model was developed to study acute and chronic hepatic hemodynamics and metabolism. 相似文献
1000.
C Sakakura Y Igarashi JK Anand KK Sadozai S Hakomori 《Canadian Metallurgical Quarterly》1996,271(2):946-952
Plasmalopsychosine, a characteristic fatty aldehyde conjugate of beta-galactosylsphingosine (psychosine) found in brain white matter, enhances p140trk (Trk A) phosphorylation and mitogen-activated protein kinase (MAPK) activity and as a consequence induces neurite outgrowth in PC12 cells. The effect of plasmalopsychosine on neurite outgrowth and its prolonged activation of MAPK was similar to that of nerve growth factor (NGF), and the effect was specific to neuronal cells. Plasmalopsychosine was not capable of competing with cold chase-stable, high affinity binding of NGF to Trk A, indicating that plasmalopsychosine and NGF differ in terms of Trk A-activating mechanism. Tyrosine kinase inhibitors K-252a and staurosporine, known to inhibit the neurotrophic effect of NGF, also inhibited these effects of plasmalopsychosine, suggesting that plasmalopsychosine and NGF share a common signaling cascade. Plasmalopsychosine prevents apoptosis of PC12 cells caused by serum deprivation, indicating that it has "neurotrophic factor-like" activity. Taken together, these findings indicate that plasmalopsychosine may play an important role in development and maintenance of the vertebrate nervous system. 相似文献