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61.
Compared 26 volunteer telephone counselors and 34 nonvolunteer undergraduates using the Tennessee Self Concept Scale, the Personal Orientation Inventory, and the Self-Disclosure Questionnaire. Results show no differences between the groups on their self-concept except in their moral-ethical perceptions of themselves. The groups did differ on the other measures. The counselors showed a pattern of responding in the Personal Orientation Inventory suggesting that they were more self-actualizing than the college group, and they indicated a greater degree of openness on the Self-Disclosure Questionnaire. Results suggest that the volunteers are altruistic in their motivation to work in this capacity and serve as important role models for their clients. (18 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Yeast-phase cells of Histoplasma capsulatum were challenged with amphotericin B, and membrane perturbation was monitored by K+ efflux. Suspensions of washed cells readily absorbed about 1.12 microgram of amphotericin B per mg (dry weight) and further nonspecific sites were also apparent. The dose-response curve for initial rate of K+ efflux was sigmoidal within the range 0.1 to 1.0 microgram of amphotericin B per ml. A fungistatic concentration of amphotericin B (0.3 microgram/ml) evoked an efflux of 85 to 90% K+ from the cells within 15 min, but cell viability decreased only 13% (yeast phase) or 33% (transformed to mycelial units). Ultrastructural changes in treated cells were detected within 5 min, and the hallmark was expansion of vacuoles during the 1-h monitoring period. In contradistinction to a previous report, the appearance of the protoplasmic membrane was not altered by fungistatic concentration. When treated cells were returned to a fresh growth medium, there was a pronounced lag (20 h). During this apparent recovery phase, the large vacuoles fragmented and returned to normal size. It is proposed that vacuoles of H. capsulatum act as a spatial buffer of considerable survival value to stressed cells.  相似文献   
63.
A review of childhood injuries at the Wesley Guild Hospital, a component of Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, Nigeria, showed that 1,471 patients seen in the children's emergency room during a period of 4 years (1992-1995) were there as a result of trauma, representing 9% of all patients seen. The case notes and accident and emergency cards of 1,224 were available for review. Ages ranged from 2 months to 15 years, with a mean of 6.9 years, and 40% of the patients were between 5 and 10 years of age. More males were affected than females, with a ratio of 1.5:1. Road traffic crashes were the most common causal factor, responsible for 324 injuries (26.5%). About 90% of these were pedestrians knocked down by automobiles and motorcycles. Passengers accounted for about 10% of the cases. Falls occurred in 305 patients (25%); 229 patients fell while on level ground either playing or running, accounting for 75%. There were 122 patients (10%) with misplaced foreign bodies; about 60% of these were recovered from the ears, and 26.3% from the nostrils. Edible seeds were the most common foreign bodies, followed by beads. Injuries from bites occurred in 108 patients, with dog and snake bites taking the lead. Burns, mainly from scalding, occurred in 89 patients. Other rare injuries were knife wounds, gunshot wounds, and injuries resulting from assaults. The home was the most common site of injury (570 patients, 46.7%) followed by streets or roadways (363 patients, 29.7%); 19.5% of injuries occurred at school. The most common anatomic region affected was the head and neck, followed by the limbs. One hundred ninety-seven patients (16%) had bony fractures, femurs being the most affected bone. Head injury was seen in 104 patients, representing 8.5%, although only 17 of these injuries were severe. There were 10 cases of abdominal injury and 9 cases of chest injury, representing 0.8 and 0.7%, respectively. Wound infection occurred in 6.4% of the patients. Death occurred in 19 patients, accounting for 1.6%; 10 of these patients had severe head injuries. Road traffic injuries and burns accounted for the greatest number of complications. The findings of this study suggest that trauma is an important factor in childhood morbidity and mortality in our environment, with road traffic injuries taking the lead. Preschool pedestrian children were most commonly affected, the majority of them on errands for their parents. We believe that the majority of these injuries are preventable.  相似文献   
64.
Modulators of P-glycoprotein (P-gp) are often themselves transported out of cells, thereby limiting their effectiveness. It may be possible to develop more effective modulators of multidrug resistance by designing drugs that irreversibly block the function of P-gp. Therefore, we studied the effect of the mustard derivatives of fluphenazine (FPN) and trans-flupenthixol (FPT) on P-gp function. Both fluphenazine-mustard (FPN-M) and trans-flupenthixol-mustard (FPT-M) possessed alkylating activity, as assayed using 4-(p-nitrobenzyl) pyridine. Multidrug-resistant MCF-7/AdrR cells were incubated with FPN or FPN-M, or FPT or FPT-M for 1 h, washed for varying number of times in phosphate-buffered saline (PBS), then resuspended in medium containing [3H]vinblastine (VBL), and assayed for steady-state accumulation of the drug. Washing had far less of an effect on the ability of FPN-M and FPT-M to increase VBL accumulation compared to their parent compounds. After eight washes in excess PBS, the cells initially exposed to FPN or FPT accumulated only 30% and 50% of the initially accumulated drug, whereas the FPN-M- or FPT-M-treated cells accumulated approximately 75% and 90% of the control, respectively. FPN-M and FPT-M also increased the uptake and decreased the efflux of VBL from MDR cells despite repeated washing. We also examined the effects of these modulators on sensitivity of MDR cells to cytotoxic agents. FPN-M and FPT-M sensitized MCF-7/AdrR cells to VBL and doxorubicin to a greater extent than their parent compounds. These studies point out the potential of "irreversible" P-gp modulators to produce prolonged chemosensitization.  相似文献   
65.
An effective topical and regional anesthetic technique using 25% cocaine paste combined with intravenous midazolam hydrochloride was used in 554 patients undergoing functional endoscopic sinus surgery. The operative fields were excellent and all procedures were completed with little patient disturbance. Patients recovered rapidly from sedation and were usually fit for discharge on the same day. There were no anesthetic complications. The major surgical complication rate was 0.5%.  相似文献   
66.
To determine if recombinant human Cu-Zn superoxide dismutase (rhSOD) would prevent acute lung injury caused by hyperoxia and barotrauma, 26 newborn piglets were studied. Ten piglets were hyperventilated (arterial PCO2 15-20 Torr) with 100% O2 for 48 h. A second group received identical treatment for 4 h (n = 2) or 48 h (n = 8) but was given 5 mg/kg of rhSOD intratracheally at time 0. Six piglets were normally ventilated (arterial PCO2 40-45 Torr) for 48 h with 21% O2. Pulmonary function and tracheal aspirates were examined at time 0 and at 24 and 48 h, and bronchoalveolar lavage was performed at 48 h. In piglets treated with hyperoxia and hyperventilation, lung compliance decreased 42%, and tracheal aspirates showed an increase in neutrophil chemotactic activity (32%), total cell counts (135%), elastase activity (93%), and albumin concentration (339%) over 48 h (P < 0.05). All variables were significantly lower in rhSOD-treated piglets and comparable to normoxic control values. Surfactant remained active in all groups. Immunohistochemistry demonstrated that at 48 h significant rhSOD was distributed homogeneously in terminal airways. Adding rhSOD to tracheal aspirates of hyperoxic hyperventilated piglets did not alter neutrophil chemotaxis, suggesting that rhSOD protected the lung by reducing the production of chemotactic mediators. Results indicate that acute lung injury caused by 48 h of hyperoxia and hyperventilation is significantly ameliorated by prophylactic intratracheal administration of rhSOD.  相似文献   
67.
Since the early 1990s, the use of ozone in many commercial and industrial laundering applications has been evolving rapidly. Ozone allows washing to be conducted using cold water, thereby saving considerable heat energy and water consumption. Additionally, ozone enhances the wash process, resulting in a significant reduction in detergent dosage and number of rinses, thus saving water. Ozone/cold water cycles are gentler to fabrics, thus extending linen life. Finally, ozone/cold water laundering is beneficial for effluents, resulting in reductions in COD (chemical oxygen demand). Microorganisms are destroyed effectively in ozone-wash waters, and washing and drying cycles are shorter, thus saving labor. In this paper, the authors describe some specific case studies at commercial laundering installations in the UK, whereby the users of ozone have reaped major benefits, including enhanced microorganism kills/inactivation and significant cost savings.  相似文献   
68.
Young men from poorer backgrounds are associated with high road traffic collision levels. However, solving this problem has proven very difficult. Hence this paper summarises the findings of a UK government funded two-year trial of a cross-discipline intervention to reduce aggressive driving amongst this group.  相似文献   
69.
70.
BACKGROUND: Antenatal testing with the nonstress test is common in the evaluation of high-risk pregnancies. A reactive test gives the clinician reassurance of fetal well-being. CASE: A 19-year-old woman, gravida 1, para 0, delivered an infant with holoprosencephaly and multiple facial and limb abnormalities at 38 weeks' gestation. The fetal heart tracing was reassuring despite the infant's compromised neurologic status. CONCLUSION: The nonstress test is dependent only upon the fetal brainstem, and it predicts oxygenation at that site rather than normality of the entire central nervous system. This limitation of the nonstress test must be remembered when performing antenatal testing.  相似文献   
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