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81.
Previous work indicates that strains of Neisseria gonorrhoeae isolated in Seattle, Wash., and Atlanta, Ga., show an association between serotypes 1 and 2 of protein I of the outer membrane and the ability to cause disseminated infection (T.M. Buchanan and J.F. Hildebrandt, Infect. Immun. 32:985-994, 1981). By using the same serotyping system, we confirmed the association between those serotypes and both disseminated infection and serum resistance in strains from North Carolina. Some strains of the same serotype had protein I species with different apparent molecular weights.  相似文献   
82.
Among the advantages offered by the lamprey brainstem and spinal cord for studies of the structure and function of the nervous system is the unique identifiability of several pairs of reticulospinal neurons in the brainstem. These neurons have been exploited in investigations of the patterns of sensory input to these cells and the patterns of their outputs to spinal neurons, but no doubt these cells could be used much more effectively in exploring their roles in descending control of the spinal cord. The variability of cell positions of neurons in the spinal cord has precluded the recognition of unique spinal neurons. However, classes of nerve cells can be readily defined and characterized within the lamprey spinal cord and this has led to progress in understanding the cellular and synaptic mechanisms of locomotor activity. In addition, both the identifiable reticulospinal cells and the various spinal nerve cell classes and their known synaptic interactions have been used to demonstrate the degree and specificity of regeneration within the lamprey nervous system. The lack of uniquely identifiable cells within the lamprey spinal cord has hampered progress in these areas, especially in gaining a full understanding of the locomotor network and how neuromodulation of the network is accomplished.  相似文献   
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What criteria would you use to assess the conceptual model you choose to guide your nursing department's practice? Whether you are assessing a model for your own use or critiquing someone else's, there are several considerations relating to the model's utility that should be kept in mind. To avoid choices based primarily on intuition or what "seems right," the author presents a framework for assessing the adequacy, completeness, and appropriateness of nursing models before their adoption for use in practice.  相似文献   
86.
Anhedonia and the deficit syndrome of schizophrenia   总被引:2,自引:0,他引:2  
Schizophrenic outpatients with and without the deficit syndrome were administered Chapman's "psychosis proneness" scales. As hypothesized, deficit syndrome patients had higher scores on Social Anhedonia and Physical Anhedonia, but did not differ from nondeficit patients on Perceptual Aberration, Magical Ideation, or Impulsive Nonconformity. The differences between the two groups were not related to race, gender, age, socioeconomic status of family of origin, or drug treatment. These results support the validity of the deficit syndrome, and suggest that the Social Anhedonia and Physical Anhedonia scales may be useful in future studies of schizophrenia.  相似文献   
87.
Fish oil (FO) diets are associated with decreased thrombosis, which is though to be related, in part, to changes in platelet and vessel wall prostanoid synthesis. Recently, we found that 13-hydroxyoctadecadienoic acid (13-HODE) synthesized in the vessel wall from linoleic acid (LA, 18:2 n-6) via the lipoxygenase pathway, also decreases platelet/vessel wall interactions. Thus, we determined whether diets containing fish oil, walnut oil (rich in linoleic acid), black currant seed oil (rich in both linoleic and gamma linolenic acids, 18:3 n-6), or lard influenced vessel wall 13-HODE synthesis and platelet/vessel wall adhesion in rabbits. In vivo, vessel wall thrombogenicity was decreased in animals fed the black currant seed oil rich diet for 4 weeks as compared to the control "LARD" diet. This latter effect was better obtained when gamma linoleic acid was present suggesting a secondary effect of this fatty acid. The decreased vessel wall thrombogenicity in those animals, was associated with increased vessel wall 13-HODE synthesis. In contrast, ex vivo platelet adhesivity was significantly decreased in the fish oil diet fed animals, as compared to the control "LARD" diet and correlated with decreased platelet 12-HETE synthesis. We conclude that both fish oil and black currant seed oil rich diets inhibit platelet/vessel wall adhesion; the black current seed oil diet by increasing the availability of linoleic acid for 13-HODE synthesis and inhibiting vessel wall thrombogenicity; the fish oil diet, by inhibiting platelet 12-HETE synthesis and subsequent platelet adhesion.  相似文献   
88.
Employment of geriatric nurse practitioners (GNPs) is one strategy to improve nursing home care. The effects of GNPs on costs and profitability of nursing homes and on costs of patient medical service use outside the nursing home are examined. Employment of GNPs does not adversely affect nursing home costs or significantly affect profits. There is some evidence of cost savings in medical service use for newly admitted patients but no evidence of savings for continuing residents. GNPs reduce the use of hospital services for both groups, and the reduction is statistically significant for newly admitted patients.  相似文献   
89.
Children with leukemia and solid tumors are often hospitalized for empiric broad-spectrum antibiotic therapy because of fever during periods of chemotherapy-induced neutropenia. Conventional practice dictates that parenteral antibiotics be continued until the patient is afebrile and has recovered from neutropenia, ie, until the absolute neutrophil count (ANC) exceeds 500 cells per cubic millimeter. However, the practice in our center has been to discontinue parenteral antibiotic therapy and discharge many such patients before resolution of neutropenia. Since the feasibility and safety of this approach has not been studied, we reviewed the records of 114 consecutive hospitalizations for fever and neutropenia in 61 patients during a 13-month period. Seventy-seven children (68%) were discharged to their homes while still neutropenic after they had been afebrile for 1 to 2 days on parenteral antibiotics, had negative blood cultures, appeared well, and usually had some evidence of bone marrow recovery. Five patients (4.4%) developed recurrent fever and required rehospitalization within 7 days of discharge. Only three of the 77 patients (3.9%) who were sent home with neutropenia had recurrent fever. Each had a brief and uneventful second hospitalization. Two of the 37 children discharged with an ANC over 500 cells per cubic millimeter required rehospitalization. A declining ANC and advanced malignancy were risk factors in predicting recurrence of fever following discharge. A rising monocyte count was a predictor of imminent recovery from neutropenia. These results suggest that "early" discharge of an afebrile yet still neutropenic patient is safe when the patient is in remission, has no evidence of serious infection, appears clinically stable, and has indications of bone marrow recovery. The conventional approach of routinely continuing the hospitalization until resolution of neutropenia may be unnecessary in such low-risk patients.  相似文献   
90.
Although the results are steadily improving, the treatment of the child with lymphoblastic leukemia in relapse remains unsatisfactory. Owing to the very nature of relapse, it is highly unlikely that future chemotherapy protocols will provide curative treatment for the majority of patients with recurrent disease. Therefore, the greatest possible emphasis must be given to further improvements and refinements in front-line (initial) therapy so as to prevent relapse from ever occurring. Our goal should be to put the relapse leukemia specialist "out of business."  相似文献   
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