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101.
102.
Edrophonium, an anticholinesterase, exerts a biphasic effect on cardiovascular autonomic drive in humans (lower doses enhance; higher doses reduce). Twenty-five anesthetized, mechanically respired (10 breaths. min(-1), constant tidal volume) patients were given either saline (n = 10) or edrophonium (0.01-1.0 mg. kg(-1), n = 15) following surgery. ECG, radial arterial pressure, and respiratory rate were sampled at 250 Hz to obtain time series for consecutive R-R intervals (RRIs), and systolic (SBP) and diastolic blood pressure (DBP). A Wigner distribution was used for time frequency mapping of spectral powers at high (HFP, 0.15-0.5 Hz) and low (LFP, 0.0-0.05 Hz) frequency. Edrophonium produced a dose-dependent decrease in heart rate [baseline 66.8 +/- 1.9 (S.E.M.) beats per minute; maximum decrease to 55.8 +/- 1.4 beats per minute with 1.0 mg. kg(-1), P < 0.01]. HFP of the RRI increased at low doses (0.2-0.4 mg. kg(-1); maximum increase to 111.0 +/- 58.2% baseline; P < 0.01) but decreased (-49.5 +/- 35.5% baseline; P < 0.01) at higher (1.0 mg. kg(-1)) doses. Edrophonium had no effect on SBP and DBP. HFP of SBP decreased with increasing doses (maximal decrease to -26.2 +/- 7.5% baseline, P < 0.01, 1.0 mg. kg(-1)). LFP of SBP was also decreased (-46.3 +/- 10.9% baseline, P < 0.01, 1.0 mg. kg(-1)). Edrophonium may enhance (lower dose) or reduce (higher dose) cardiovascular autonomic drive in humans, as evidenced by the significant changes it evokes in HFP of the RRI (parasympathetic drive), and in the HFP and LFP of SBP (sympathetic drive). These observations may account for the modest autonomic side effects of edrophonium when this drug is used clinically.  相似文献   
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Abstract Traditional Native American people are experiencing serious health, economic, and social problems resulting from alcoholism. Native Americans maintain a worldview of health and illness that conflicts with the dominant culture's approach to treatment. The purposes of this study were to describe the health beliefs of traditional Muscogee (Creek) Indians concerning the causes of illness and learn how these beliefs relate to alcoholism. The researchers conducted in-depth interviews of 55 traditional Muscogee (Creek) participants to learn traditional beliefs about illness and alcoholism. Data were analyzed using content analysis. Results indicate that both illness and alcoholism are perceived as having natural and unnatural (supernatural) causes. A challenge facing nurses is how to provide culturally sensitive care when clients' and nurses' beliefs about the cause of alcoholism may be in conflict. The authors discuss preservation, accommodation, and repatterning of health care beliefs as a basis for planning culturally sensitive nursing care.  相似文献   
105.
A brief overview is provided of the bioactivity of macrolides against a range of bacterial species. Topics considered include the cellular pharmacokinetics of uptake and efflux of these drugs and the importance of intra- or extracellular and cytoplasmic or granular location on their activity. Emphasis is placed on the importance of synergy between macrolides and host defenses, with drug accumulation producing modification of cellular function, such as enhancement of phagocytosis, and exocytosis of polymorphonuclear neutrophils. Such interaction may explain the activity of such agents against organisms which normally inhibit fusion of phagolysosomes.  相似文献   
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107.
Executive and compensatory memory retraining in traumatic brain injury   总被引:3,自引:0,他引:3  
A controlled treatment outcome study was conducted comparing the efficacy of memory remediation treatment with no treatment on traumatic brain-injury patients. The memory remediation treatment consisted of both compensatory and executive training skills and was delivered 6 hours weekly over a 2 1/2-week period. Six subjects in the treatment group and 6 subjects in the control group were matched on WAIS-R FSIQ scores, pre-test memory scores and age. Pre-and post-test measures were obtained for both groups on a paragraph memory task. A significant difference was demonstrated between the treatment and control post-test memory scores. The experimental group significantly improved memory scores beyond that of the control group, suggesting that memory remediation is effective for head-injury patients with memory deficits. Discussion of findings and suggestions for further investigation are presented.  相似文献   
108.
The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function.  相似文献   
109.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
110.
During the period 1981–1986, 1605 infants presenting a major congenital heart defect (CHD) were identified in Sweden. Using the personal identification numbers of the mothers, 1507 of them could be linked to the Medical Birth Registry and two controls were selected for each infant. For this total of 4521 infants, 2686 postoccurrence sibs born during the period 1981–1989 were identified from the Medical Birth Registry. The tendency to have one or more sibs was higher among cases than among controls and was correlated to the life status of the proband. This tendency did not vary according to the type of CHD when controlling for life status. The prevalence at birth of CHD was almost four times higher among sibs of CHD infants than among sibs of normal infants. The tendency to have a sib with an extracardiac malformation did not differ between CHD probands and normal probands. The importance of only including births occurring after the proband when evaluating recurrence risks is stressed. © 1994 Wiley-Liss, Inc.  相似文献   
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