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71.
72.
A 17-year-old male presented to a local hospital with symptoms of pneumonia and a hacking cough productive of yellow sputum. Direct examination of a bronchial lavage sample revealed organisms morphologically consistent with Blastomyces dermatitidis, which was confirmed by culture. The patient was placed on intravenous antifungal therapy and his condition improved dramatically. OBJECTIVES: to describe the gross and microscopic morphologies of both yeast and mold forms of B. dermatitidis; to identify B. dermatitidis given patient history, and microscopic and colony morphology; to describe the symptoms of primary pulmonary infections caused by B. dermatitidis, and to name additional tissues typically affected by the systemic pathogen.  相似文献   
73.
There is a wealth of material on 'how to do' change plus empirical work revealing change process complexity. In health care, the relevance of context is highlighted, but studies of rural health-care change have focused on community impacts. There is little to inform health-care managers of how remoteness and rurality impact upon change processes. This study considered Scottish maternity units and aimed to identify issues in the change process associated with rurality and remoteness. Six units were purposively selected and 131 interviews were conducted with managers, staff and community members over 15 months. Analysis induced themes pertinent to remoteness and rurality. These included: perceived 'distance' between senior managers imposing change and the wider community of staff and residents; perceptions of community vulnerability; and tensions arising from working in small teams and living in small communities. The study provides useful insights for rural managers at a time of considerable service reconfiguration.  相似文献   
74.
75.
An evaluative research study was conducted to examine the construct validity and applicability of a selected clinical-performance-evaluation tool. The tool was designed for baccalaureate students in a community health nursing course. Eighteen senior students functioning in two urban clinical agencies participated in the study. Data were collected at two evaluation points over one semester. Results indicated strong support for construct validity of the tool. This finding suggests a high level of correlation between theoretical concepts and clinical practice. Recommendations for use of the clinical performance evaluation tool are discussed.  相似文献   
76.
While waiting to observe the response to ibutilide fumarate by a patient with atrial fibrillation, a nurse preparing the intravenous solution inadvertently spilled the drug on the hands of a medical resident. The resident immediately wiped his hands dry with disposable paper towels. Several hours later he sensed tingling and itching over the area, and the next day two erythematous bullous lesions were present on the dorsal surfaces of both hands. A single application of topical steroid was applied to the affected areas. The lesions were kept clean and dry, and healed completely in approximately 10 days. This is an unusual allergic reaction due to contact with ibutilide fumarate.  相似文献   
77.
Nonepileptic Posttraumatic Seizures   总被引:4,自引:2,他引:2  
Summary: Purpose: Epileptic posttraumatic seizures (PTSs) are a well-recognized consequence of head injury (HI), but HI and nonepileptic seizures (NESs) have not been related. We describe a significant subset of patients with NESs who had their seizures attributed to HI.
Methods: We reviewed the records of all patients diagnosed with NES at the University of Maryland Medical Center over a 6-year period (1989–1995) and selected patients with seizures attributed to a head injury occurring ≥3 years before the onset of their seizures.
Results: Of 157 patients with video-EEG confirmed NES, 37 (24%) had the onset of their seizures attributed to an HI. Their average age was 34 years (range, 15–56 years); 68% were women. Nonepileptic PTS usually developed within the first year after HI (89%). Convulsive symptoms were present in 54%. Whereas epileptic PTSs characteristically follow severe HI, the majority (78%) of our patients with nonepileptic PTSs sustained only mild HI. Before their HI, 76% of our patients were employed, working in the home, or students, but only 11% could continue those activities after developing nonepileptic PTSs.
Conclusions: Nonepileptic PTSs are frequently mistaken for epileptic PTSs and result in serious disability. The misdiagnosis of nonepileptic PTSs leads to ineffective and inappropriate treatment. Patients with intractable seizures after HIS, articularly mild HIS, should be carefully evaluated for NESs.  相似文献   
78.
Arachidonic acid (AA), released in response to muscarinic acetylcholine receptor (mAChR) stimulation, previously has been reported to function as a reversible feedback inhibitor of the mAChR. To determine if the effects of AA on binding to the mAChR are subtype specific and whether AA inhibits ligand binding to other G protein-coupled receptors (GPCRs), the effects of AA on ligand binding to the mAChR subtypes (M1, M2, M3, M4, and M5) and to the μ-opioid receptor, β2-adrenergic receptor (β2-AR), 5-hydroxytryptamine receptor (5-HTR), and nicotinic receptors were examined. AA was found to inhibit ligand binding to all mAChR subtypes, to the β2-AR, the 5-HTR, and to the μ-opioid receptor. However, AA does not inhibit ligand binding to the nicotinic receptor, even at high concentrations of AA. Thus, AA inhibits several types of GPCRs, with 50% inhibition occurring at 3–25 μM, whereas the nicotinic receptor, a non-GPCR, remains unaffected. Further research is needed to determine the mechanism by which AA inhibits GPCR function.  相似文献   
79.
The term "health state utility" implies the assigning of a numerical value to a state of health. Assessment of the success of health care procedures, using health state utilities, enables evaluation of available treatments and procedures in terms of differing health outcomes and therefore facilitates cost-benefit analyses. Although measurement of general health state utilities has become increasingly common in medicine using a variety of techniques, few attempts have as yet been made in dentistry to place valuations on different dental health states. The absence of tried and tested methods for measuring tooth quality make the benefits gained from preventive and restorative dental programmes difficult to quantify. The aim of this study was to assess the average utility values, held by a group of dentists and a group of members of the general public, for four different tooth states which it was hypothesised would have different values. These were 1) a decayed and painful posterior tooth; 2) a decayed and non-painful posterior tooth; 3) a posterior tooth which had been restored and would need further restorative treatment and 4) a permanently restored posterior tooth. A standard gamble questionnaire was used to elicit the utility values which were then substituted as "weightings" in a modified version of the "T-health" index (1). The results show that it is possible to assess dental health state utility values using the standard gamble method and that the average utility values of the dentists in the study were consistently higher than those of the general public.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
80.
Whirling disease: re-emergence among wild trout   总被引:6,自引:0,他引:6  
Summary: Whirling disease of rainbow trout is caused by Myxobolus cerebralis, a myxozoan parasite possessing a life cycle well adapted to the natural environments where salmonid fish are found. Whirling disease was first described in Europe in 1898 among farmed rainbow trout but recent occurrences have been devastating to wild trout in North America. The disease is considered a major threat to survival of wild rainbow trout in the intermountain west of the United States. Difficulties in containing the spread and potentially eliminating the pathogen are tied to features of a complex life cycle involving two hosts, the salmonid fish and an aquatic oligochaete. Details of the morphologic development of the parasite have been described in each host but only now are we beginning to appreciate the breadth of interactions between these developmental forms and the sequential responses of the host. Fundamental mechanisms of the recognition and attachment of the parasite to the hosts, how host immunity is evaded and the unknown influences of environmental factors all contribute to a rather poor understanding of the biology of the parasite. Although the biology and ecology of the salmonid host are better known than for the oligochaete host, our knowledge is inadequate to interpret their complex interactions with the parasite. This uncertainty precludes the development of effective management activities designed to enhance the viability and productivity of wild trout populations in M. cerebralis- positive river systems. Improving our understanding of the hosts, the parasite and the environmental factors determining their interaction should provide for more focused and effective control methods for containing the spread and devastating effects whirling disease is causing to our wild trout populations.  相似文献   
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