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31.
Differential Effects of Clostridium difficile Toxins on Tissue-Cultured Cells 总被引:13,自引:4,他引:13
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Sam T. Donta Nadine Sullivan Tracy D. Wilkins 《Journal of clinical microbiology》1982,15(6):1157-1158
Two immunologically distinct Clostridium difficile toxins elicited similar morphological changes on cultured cells, although there were differences in both toxin potency and cell sensitivities. 相似文献
32.
Various forms of electronic health records (EHRs) are currently being introduced in several countries. Nurses are primary stakeholders and need to ensure that their information and knowledge needs are being met by such systems information sharing between health care providers to enable them to improve the quality and efficiency of health care service delivery for all subjects of care. The latest international EHR standards have adopted the openEHR approach of two-level modelling. The first level is a stable information model determining structure, while the second level consists of constraint models or 'archetypes' that reflect the specifications or clinician rules for how clinical information needs to be represented to enable unambiguous data sharing. The current state of play in terms of international health informatics standards development activities is providing the nursing profession with a unique opportunity and challenge. Much work has been undertaken internationally in the area of nursing terminologies and evidence-based practice. This paper argues that to make the most of these emerging technologies and EHRs we must now concentrate on developing a process to identify, document, implement, manage and govern our nursing domain knowledge as well as contribute to the development of relevant international standards. It is argued that one comprehensive nursing terminology, such as the ICNP or SNOMED CT is simply too complex and too difficult to maintain. As the openEHR archetype approach does not rely heavily on big standardised terminologies, it offers more flexibility during standardisation of clinical concepts and it ensures open, future-proof electronic health records. We conclude that it is highly desirable for the nursing profession to adopt this openEHR approach as a means of documenting and governing the nursing profession's domain knowledge. It is essential for the nursing profession to develop its domain knowledge constraint models (archetypes) collaboratively in an international context. 相似文献
33.
Phagosomal processing of Mycobacterium tuberculosis antigen 85B is modulated independently of mycobacterial viability and phagosome maturation
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Ramachandra L Smialek JL Shank SS Convery M Boom WH Harding CV 《Infection and immunity》2005,73(2):1097-1105
Control of Mycobacterium tuberculosis infection requires CD4 T-cell responses and major histocompatibility complex class II (MHC-II) processing of M. tuberculosis antigens (Ags). We have previously demonstrated that macrophages process heat-killed (HK) M. tuberculosis more efficiently than live M. tuberculosis. These observations suggested that live M. tuberculosis may inhibit Ag processing by inhibiting phagosome maturation or that HK M. tuberculosis may be less resistant to Ag processing. In the present study we examined the correlation between M. tuberculosis viability and phagosome maturation and efficiency of Ag processing. Since heat treatment could render M. tuberculosis Ags more accessible to proteolysis, M. tuberculosis was additionally killed by antibiotic treatment and radiation. Processing of HK, live, radiation-killed (RadK), or rifampin-killed (RifK) M. tuberculosis in activated murine bone marrow macrophages was examined by using an I-A(b)-restricted T-cell hybridoma cell line (BB7) that recognizes an epitope derived from Ag 85B. Macrophages processed HK M. tuberculosis more rapidly and efficiently than they processed live, RadK, or RifK M. tuberculosis. Live, RadK, and RifK M. tuberculosis cells were processed with similar efficiencies for presentation to BB7 T hybridoma cells. Furthermore, phagosomes containing live or RadK M. tuberculosis expressed fewer M. tuberculosis peptide-MHC-II complexes than phagosomes containing HK M. tuberculosis expressed. Since only live M. tuberculosis was able to prevent acidification of the phagosome, our results suggest that regulation of phagosome maturation does not explain the differences in processing of different forms of M. tuberculosis. These findings suggest that the mechanisms used by M. tuberculosis to inhibit phagosomal maturation differ from the mechanisms involved in modulating phagosome Ag processing. 相似文献
34.
Sam Tsemberis E. Sally Rogers Eleni Rodis Patricia Dushuttle Vicki Skryha 《Journal of community psychology》2003,31(6):581-590
Provision of residential services to people with mental illness has assumed increasing importance since deinstitutionalization and as community‐ based services have increased. This large‐scale multisite study of housing programs specifically for persons with mental illness examines one of the factors that lead to successful residential tenure for persons with serious mental illness. To date, the Lehman Quality of Life Scale has been used primarily to assess satisfaction with housing in studies of residential services. This article reports on a new measure of housing satisfaction. This new 25‐item instrument was developed, field tested in a variety of housing settings across the country, and analyzed for reliability and validity by a group of housing researchers and clinicians. The implications of using this instrument for future evaluation and research on housing for persons with mental illness are examined. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 581–590, 2003. 相似文献
35.
Navin Wadehra Sherif Farag Brian Bolwell Patrick Elder Sam Penza Matt Kalaycio Belinda Avalos Brad Pohlman Guido Marcucci Ronald Sobecks Thomas Lin Steven Andrèsen Edward Copelan 《Biology of blood and marrow transplantation》2006,12(12):1343-1349
Busulfan (Bu)-based preparative regimens have not been extensively investigated in Hodgkin disease (HD). The purposes of this study were to investigate the toxicity and efficacy of a novel preparative regimen of Bu 14 mg/kg, etoposide 50-60 mg/kg, and cyclophosphamide 120 mg/kg in patients with primary refractory and relapsed HD. One hundred twenty-seven patients with a median age of 33 years (range, 14-67 years) underwent transplantation. The regimen was well tolerated, with 5.5% treatment-related mortality at 100 days after transplantation. With a median follow up of 6.7 years, the 5-year progression-free survival was 48 +/- 5%, and the 5-year overall survival was 51 +/- 5%. A Cox proportional hazards model identified refractory disease at time of transplantation as the only significant factor affecting relapse and overall survival, whereas disease bulk >10 cm affected overall survival. Five patients died between 5.3 and 9.3 years of late complications, including secondary myelodysplasia or acute myeloid leukemia, secondary solid malignancies, and pulmonary toxicity. This novel Bu regimen is comparable to other radiation-free preparative regimens in its effectiveness in the control of HD and with a low-risk of early treatment-related mortality. 相似文献
36.
Monfraix S Bayat S Porra L Berruyer G Nemoz C Thomlinson W Suortti P Sovijärvi AR 《Physics in medicine and biology》2005,50(1):1-11
The aim of this study was to assess the feasibility of a novel respiration-gated spiral synchrotron radiation computed tomography (SRCT) technique for direct quantification of absolute regional lung volumes, using stable xenon (Xe) gas as an inhaled indicator. Spiral SRCT with K-edge subtraction using two monochromatic x-ray beams was used to visualize and directly quantify inhaled Xe concentrations and airspace volumes in three-dimensional (3D) reconstructed lung images. Volume measurements were validated using a hollow Xe-filled phantom. Spiral images spanning 49 mm in lung height were acquired following 60 breaths of an 80% Xe-20% O2 gas mixture, in two anaesthetized and mechanically ventilated rabbits at baseline and after histamine aerosol inhalation. Volumetric images of 20 mm lung sections were obtained at functional residual capacity (FRC) and at end-inspiration. 3D images showed large patchy filling defects in peripheral airways and alveoli following histamine provocation. Local specific lung compliance was calculated based on FRC/end-inspiration images in normal lung. This study demonstrates spiral SRCT as a new technique for direct determination of regional lung volume, offering possibilities for non-invasive investigation of regional lung function and mechanics, with a uniquely high spatial resolution. An example of non-uniform volume distribution in rabbit lung following histamine inhalation is presented. 相似文献
37.
BACKGROUND: Coordination of nonverbal behaviour during interactions is a prerequisite for satisfactory relationships. Lack of coordination may form a risk factor for depression. The 'vulnerability-accumulation hypothesis' assumes that vulnerability to recurrence of depression will increase with increasing experience of depressive episodes. Therefore it is expected that interviewers and patients remitted from a recurrent episode of depression would reach less coordination during a clinical interview compared to interviewers and patients remitted from a first lifetime episode. Moreover, we assumed that prior severity of depression modifies this reciprocal coordination process. METHODS: During discharge interviews, interviewers were videotaped in interaction with remitted patients with unipolar major depression recurrent depression (REC); n=28; first episode (SEP); n=22. Durations and frequencies of nonverbal involvement behaviour was registered during the first 15 min. Involvement of the patients consisted of gesticulating, looking at the interviewer, and general head movements; yes--nodding and hm, hm, yes, yes reflected involvement of the interviewer. Coordination between patients and interviewers was analyzed per 3-min epochs and defined as 'attunement': the absolute difference between patients' and interviewers' involvement. Averaged attunement, its time course and variability (presumably reflecting control of the attunement process) were assessed. RESULTS: The time course of nonverbal attunement differed between the REC and SEP condition. A larger variability of attunement was found in patients remitted from a relatively severely depressed episode, compared to patients remitted from a severe first life time episode. No other significant differences were found. CONCLUSIONS: Partial support was found for the notion that nonverbal vulnerability accumulates in depression and that the severity of prior depression modifies this process. 相似文献
38.
ACE Genotype May Have an Effect on Single versus Multiple Set Preferences in Strength Training 总被引:1,自引:0,他引:1
Colakoglu M Cam FS Kayitken B Cetinoz F Colakoglu S Turkmen M Sayin M 《European journal of applied physiology》2005,95(1):20-26
A polymorphic variant of the human angiotensin converting enzyme (ACE) gene was identified. The 'D' (rather than 'I') variant was associated with improvements in strength related to physical training. We set out to determine whether the response to different patterns of strength training might also differ. Ninty-nine Caucasian male non-elite athletes were randomly allocated into one of three groups: 31 non-training/control (CG: 31), single-set (SSG: 35) and multiple-set (MSG: 33). SSG and MSG trained three times a week for 6 weeks. Both training groups were underwent a strength-training program with two mesocycles (12-15 repetition maximum (RM) and 8-12 RM mesocycles). One RM loads in half squat and bench press were assessed before training and after the first and second mesocycles. ACE polymorphisms analysed by polymerase chain reaction (PCR) methods. Subjects with ACE II genotype in the MST group had improved strength development in 12-15 RM, while SST and MST groups had similar gains in 8-12 RM. Subjects with ACE DD genotype in both the SSG and the MSG had similar benefits from both 12-15 RM and 8-12 RM. Strength gains for subjects with ACE ID genotype in the SSG were similar to MSG gains in response to 8-12 RM loads but not with 12-15 RM loads. Additionally, subjects with DD genotype had superior strength gains in both strength training groups. Tailoring strength training programmes (single-set vs. multiple set) according to the athlete's ACE genotype may be advantageous. 相似文献
39.
Hibbitts S Rahman A John R Westmoreland D Fox JD 《Journal of virological methods》2003,108(2):145-155
New methods for the detection of human parainfluenza viruses (HPIVs) were developed. These were based on nucleic acid sequence-based amplification (NASBA) and utilised the NucliSens Basic Kit. Primers and probes were selected from the haemagglutinin neuraminidase (HN) gene of HPIV1, HPIV2 and HPIV3, and from the phosphoprotein (P) of HPIV4a and -4b. Synthetic RNA, titrated control virus stocks and respiratory specimens (n=44) were utilised to evaluate performance of the assays. Detection of NASBA products was by probe hybridisation and electrochemiluminescence (ECL) ('end-point' detection) or using molecular beacons ('real-time' detection). The assays using ECL detection proved to be both sensitive and specific. Typically, less than or equal to 100 RNA copies or one TCID(50) input was detectable with no cross-reaction between the specific HPIV assays and other respiratory viruses. Results for clinical samples were concordant with those obtained by 'conventional' procedures by classical viral diagnostic methods. 'Real-time' detection utilised probes specific for either HPIV1 or HPIV3 with similar performance characteristics to the assays with 'end-point' detection. The feasibility of multiplexing targets together was confirmed using a combined HPIV1 and HPIV3 assay with good results for ECL and molecular beacon detection on control material and clinical samples. 相似文献
40.
Ozçelik B Serin IS Basbug M Uludag S Narin F Tayyar M 《Human reproduction (Oxford, England)》2003,18(8):1703-1706
BACKGROUND: Our main aim was to investigate the effects of melatonin (ME), possibly the most powerful free-radical scavenger, on the prevention of i.p. adhesion formation in rat uterine horn. Our secondary aim was to determine whether different methods of administration of ME were beneficial. METHODS: Animals were randomly assigned into seven groups, each consisting of 13 rats. Measured serosal injury was created using a standard technique. While control and two sham groups were not given ME, two of the remaining four groups were given a single dose of 10 mg/kg (2 mg) of ME i.p. immediately after injury and 30 min prior to injury respectively. In the two other groups, ME treatment was continued daily for 5 days. All animals were killed 2 weeks after surgery and adhesions were determined and scored by a examiner blinded to the test. RESULTS: The extent, severity and total scores of adhesion were found to be significantly reduced in all of the ME treatment groups when compared with control and sham groups. There were no statistically significant differences between the treatment groups. CONCLUSIONS: This study showed that even single dose ME therapy was effective in the prevention of post- operative i.p. adhesion formation. 相似文献