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121.
Identification of receptor ligands with phage display peptide libraries.   总被引:18,自引:0,他引:18  
With the development and maturation of the technology of displaying peptides on bacteriophage, it has become possible to isolate peptide ligands to various targets. In the phage display strategy, up to 10(9) peptides of different permutations are expressed on the surface of filamentous phage. Thus, peptides capable of binding target molecules in vitro and even target tissues in vivo can be identified. In recent years, a series of libraries that display degenerate peptides of different lengths have been constructed, and specific ligands to cell surface receptors, such as integrins, have been isolated. In the in vivo biopanning, peptides targeting distinct organs or tumors have been rescued after intravenous administration of phage libraries into mice. In one application, the isolated peptide ligands have been used to direct a cytotoxic drug to tumor vasculature in mice. Further applications in radioimaging and radiotherapy are being investigated.  相似文献   
122.
94 patients with refractory multiple myeloma were treated in a multicentre trial with combinations of cytotoxic drugs including anthracyclines. All were refractory to a 5-drug combination containing 3 alkylating agents, vincristine and methylprednisolone (MOCCA). With a combination of epirubicin and iphosphamide a 50% response was achieved in 9% of 22 patients. The response rate after schedule VAP (vincristine, doxorubicin and prednisolone) was 8% of 13 patients and that after schedule VAD (vincristine, doxorubicin and dexamethasone) 20% of 59 patients. The previous chemotherapy had lasted for less than 12 months in 13 cases from among all these patients, and 5 of these (38%) responded. In contrast, there were only 10 responders (12%) among the 81 patients with longer previous chemotherapy.  相似文献   
123.

Background  

Reduced placental perfusion predisposes to the maternal syndrome pre-eclampsia characterized by systemically reduced perfusion. Considerable data support the role of angiogenic factors in the development of the maternal syndrome. Hypoxia-inducible factor (HIF-1) mediates the cellular responses to hypoxia e.g. by promoting angiogenesis.  相似文献   
124.
Goals of work The purpose of this study was to better understand various variables related to food intake and eating problems in children with cancer during their chemotherapy.Patients and methods Twenty-two consecutively admitted children, diagnosed with cancer and undergoing chemotherapy, participated in this study. Twenty-one of them, their parents and attending nurses participated in semi-structured interviews. Ten of the children underwent a taste acuity test, and recognition thresholds for the four basic tastes were determined.Main results The shared view of both children and parents was that altered taste was the predominant cause of the eating problems. In contrast, the nurses perceived that nausea was the most important cause of the children’s eating problems. In addition, psychological aspects such as learned food aversions and negative attitudes towards hospital food were regarded as important by children, parents and nurses. The taste test showed that the patients had higher thresholds for bitter taste and made more taste recognition errors compared to controls.Conclusions Changes seem to exist both in the primary gustatory sense as well as in food perception in paediatric cancer patients undergoing chemotherapy. Single solutions, such as efforts to serve “tasty food”, do not suffice alone. A more effective solution may be to combine different strategies and combinations of oral, enteral and parenteral nutrition should be considered to prevent malnutrition.  相似文献   
125.
Online health promotion materials have great potential to reach persons with disabilities and provide valuable information to this vulnerable population. While health promotion efforts are important for everyone, they are crucial for individuals with disabilities. Yet information needed to support these efforts is often presented in such a way that its access is limited or its content is inappropriate for this population. Whether designing or selecting online materials for individuals with disabilities, nurses can benefit from knowledge about strategies to make web sites more accessible or to assess the accessibility of existing web sites. The task of providing health promotion information to women with disabilities was undertaken as part of the "Health Promotion for Women with Disabilities Project" at Villanova University's College of Nursing. A web site was created as one method of providing information. This paper presents strategies that are used to make this site accessible.  相似文献   
126.
Mutations in the quinolone resistance-determining region of the gyrA gene from 138 ciprofloxacin-resistant (MIC, > or =4 microg/ml) and 24 ciprofloxacin-susceptible (MIC, < or =1 microg/ml) clinical Campylobacter jejuni isolates were subjected to single-strand conformation polymorphism analysis and sequencing. All of the isolates could be assigned to three genotypic clusters based on silent mutations. All resistant isolates had a point mutation at codon 86.  相似文献   
127.
The Classification of Nursing Interventions research team at The University of Iowa, College of Nursing is building a taxonomy of nursing interventions that will include all of the direct care treatment activities that nurses perform on behalf of patients. This report describes the study in which 12 nursing interventions and their associated activities for care of the integument were extracted from a large database and validated through a two-round Delphi survey. Using an adaptation of Fehring's model for determining diagnostic content validity of nursing diagnoses, a definition, critical activities, and supporting activities were developed for each of the following interventions: Bathing, Bedrest Care, Hair Care, Nail Care, Oral Health Maintenance, Oral Health Promotion, Oral Health Restoration, Positioning, Pressure Management, Skin Care–Topical Treatments, Skin Surveillance, and Wound Care. Further research is needed to validate supporting activities and to continue classifying interventions and activities that nurses use in treating impaired skin integrity (potential and actual) and altered oral mucous membrane integrity (potential and actual).  相似文献   
128.
129.
Mulibrey nanism (MUL) is an autosomal recessive disorder that is enriched in the Finnish population. Variable degrees of pericardial and myocardial involvement can lead to heart failure and premature death. The purpose of this study was using magnetic resonance imaging (MRI) to assess structural and functional abnormalities of the MUL cardiopathy in all four cardiac chambers as well as in the pericardium. Thirty-one patients with MUL (mean age 27, range 15-50 years) and 16 controls (mean age 31, range 19-45 years) were examined with a Siemens Vision 1.5-T imager. Ten patients had undergone pericardiectomies to relieve symptoms of constrictive pericarditis. In surgery performed 0.5-25 years before MRI, the removed pericardium was found to be thickened and consisting of scarlike fibrosis. Turbo spin echo images were obtained for assessment of pericardial thickness, and breath hold left ventricular (LV) short axis and four-chamber cine images were obtained for the volumetric data. In MRI, pericardial thickness was normal (under 3.4 mm) in all patients with MUL. In the 10 pericardiectomized patients, the remnants of the pericardium were of normal thickness as well. The LV septum (p = 0.01) and posterior wall (p<0.001) were hypertrophied and end-diastolic volumes of both ventricles (p<0.05) were reduced in all patients. The LV systolic function was preserved. The volume chance during the first third of diastole (p = 0.030), the absolute peak filling rate (p = 0.047), and the time to peak rate of LV diastolic filling (p = 0.030) indicated restrictive LV diastolic filling. The right ventricular ejection fraction and contraction of both atria were reduced.  相似文献   
130.
OBJECTIVES: To report data on current nurse practice behaviors related to evidence-based assessment of acute pain in older adults, perceived stage of adoption of pain assessment practices, and perceptions of barriers to optimal assessment in this population. METHODS: Medical records from 709 older adult patients hospitalized with hip fractures from 12 acute care settings were abstracted for nurse assessment practices during the first 72 hours after admission. Questionnaires sent to nurses on study units regarding perceived stage of adoption and barriers to assessment in older adults. RESULTS: Data revealed several areas in which pain assessment practices were not optimal. Pain was not routinely assessed every 4 hours, and pain location was assessed even less frequently. Pain behaviors were assessed more in patients with a diagnosis of dementia compared to those without dementia, but the frequency of pain behavior assessments was low. Pain was not routinely assessed within 60 minutes of administering an analgesic. Nurses reported not using optimal pain assessment practices even when they were aware of and persuaded that those practices were desirable. In addition, nurses reported that difficulty communicating with patients created the greatest challenge in managing pain. CONCLUSIONS: Our data suggest that pain is not being assessed and reassessed in a manner that is consistent with current practice recommendations in older adult patients with pathologic processes that highly suggest the presence of acute pain.  相似文献   
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