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61.
OBJECTIVE: The purpose is to examine the responsiveness of the Health Utilities Index Mark 2 (HUI2), Mark 3 (HUI3), and other generic and disease-specific measures in osteoarthritis patients undergoing total hip arthroplasty (THA). METHODS: Ninety patients (mean age=68.13; SD=8.15) on a waiting list for THA completed measures that included the standard gamble, HUI2, HUI3, SF-36, Harris Hip Scale, WOMAC, and MACTAR. before and after THA. Responsiveness statistics (effect size, standardized response mean, Guyatt's responsiveness statistic, paired-sample t-tests, and relative efficiency statistic) were calculated. RESULTS: The disease-specific measures were more responsive than the generic measures. Rankings of the degree of responsiveness varied depending on the responsiveness statistic used. CONCLUSIONS: Disease-specific measures are the most responsive in THA patients. However, the SF-36, HUI2, and HUI3 had summary scores and domain/attributes scores that were also responsive and provided additional information. Among the generic measures, HUI3 was the most responsive.  相似文献   
62.
Tumor oxygen status is a reliable prognostic marker that impacts malignant progression and outcome of tumor therapy. However, tumor oxygenation is heterogeneous and cannot be sufficiently described by a single parameter. It is influenced by several factors including microvessel density (MVD), blood flow (BF), blood volume (BV), blood oxygen saturation, tissue pO(2), oxygen consumption rate, and hypoxic fraction. The goal of this investigation was to integrate these measurements to obtain a comprehensive profile of tumor oxygenation. Platelet/endothelial cell adhesion molecule immunohistochemistry, the recessed oxygen microelectrode, color and power Doppler ultrasound (DUS), and diffuse light spectroscopy (DLS) were used to measure tumor oxygen status using vascular endothelial growth factor (VEGF)-transfected hypervascular human melanoma xenografts and their nontransfected counterparts as a model. NIH1286 human melanoma cells were transfected with a retroviral vector +/- a 720-bp fragment of human VEGF(121). High VEGF-producing clones were selected by ELISA. Oxygen consumption rate was measured in NIH1286/VEGF+ [VEGF-transfected cells (VEGF+ cells)] and NIH1286/Vec cells [cells transfected with vector alone (Vec cells)] using a standard Clark oxygen electrode. Athymic nude 6-8-week-old mice received s.c. injection in the right flank with 5 x 10(6) VEGF+ or Vec cells. When tumors were 10-14 mm in maximum dimension, serum was analyzed for VEGF by ELISA. Cryopreserved tumor tissue sections were immunostained for platelet/endothelial cell adhesion molecule, and MVD measurements were made. Tumor-bearing mice were anesthetized, and pO(2) measurements were made using Eppendorf pO(2) histograph or the recessed oxygen microelectrode. Tumor BF and BV were measured by quantitative analysis of DUS images. DLS was used to measure tumor BF and blood oxygen saturation variation. VEGF+ cell supernatants had 15,500 pg/ml VEGF, and Vec cells had 10 pg/ml. VEGF+ and Vec cells had equivalent oxygen consumption rates. VEGF+ tumors had a faster growth rate than Vec tumors. Serum from VEGF+ tumor-bearing mice showed 4,211 pg/ml VEGF, whereas VEGF was undetectable in the serum of control mice. MVD values were 74 +/- 11 in VEGF+ tumors and 39 +/- 4 in control tumors at x200 magnification/0.95-mm(2) area. The median pO(2) values were 3.5-fold higher in VEGF+ tumors than in Vec tumors by the recessed oxygen microelectrode and 18-fold higher by Eppendorf pO(2) histograph. DUS showed a 3.3-fold higher mean BF and a 5.5-fold higher BV in VEGF+ tumors than in Vec tumors. DLS showed a 3.2-fold higher mean BF and 1.7-fold higher oxygen saturation in the hypervascular tumors as compared with the control tumor type, consistent with increased BF and BV data by DUS. An integrated approach that yields a comprehensive and consistent profile of oxygen status in tumors could potentially provide critical information for prognosis and treatment.  相似文献   
63.
In England, the education of nurses in the academic arena has a relatively short history arguably representing recent advancement of the nursing discipline. Until we undertook this study, however, expectations for the next decade were unknown. The current investigation replicates a similar study of Australian nurse academics (Sellers & Deans, 1996) which found discrepancies between how nurse academics perceived the future development of the profession, compared to how they actually expected it to develop. In order to provide information concerning the future of nursing education in England and related professional and social factors, a random sample of nurse academics was surveyed. Findings indicate that although advances have been made, there are a number of concerns regarding the development of nursing as a discipline. These include parity of status with other academic areas, resource issues, the workload of nurse academics and the perception that there is lack of cohesiveness amongst nurses as a professional group. Findings in this study closely mirror results in the Australian study indicating similarities in how the nursing profession copes with the transition from a predominantly hospital based education program to a program grounded in academic institutions.  相似文献   
64.
BACKGROUND AND PURPOSE: Current imaging does not permit quantification of neural injury after traumatic brain injury (TBI) and therefore limits both the development of new treatments and the appropriate counseling of patients concerning prognosis. We evaluated the utility of magnetization transfer ratio (MTR) and proton MR spectroscopy in identifying patients with neuronal injury after TBI. METHODS: Thirty patients with TBI (21-77 years old; mean age, 42 years; admission Glasgow Coma Scale (GOS) scores 3-15; mean score, 11) were studied on a 1.5-T system with magnetization transfer imaging and MR spectroscopy of the splenium. Magnetization transfer imaging was also performed in the brain stem in all patients, and other areas of the brain were sampled in one patient. The splenium of the corpus callosum and brain stem were studied because these are often affected by diffuse axonal injury. Scans were obtained 2 to 1129 days after injury (median, 41 days). MTR was considered abnormal if it was more than 2 SD below normal. Proton MR spectroscopy was used to calculate the N-acetylaspartate (NAA)/creatine (Cr) ratio. GOS was determined at least 3 months after injury. RESULTS: In 10 patients with a GOS of 1 to 4, the mean NAA/Cr was 1.24 +/- 0.28; two of these patients had abnormal MTR in normal-appearing white matter (NAWM). In 20 patients with a GOS of 5, the mean NAA/Cr was 1.53 +/- 0.37 (P < .05); four of these patients had abnormal MTR in NAWM. MTR abnormalities in NAWM were identified in six patients, but these changes did not correlate with GOS or MR spectroscopy changes. CONCLUSION: MTR and MR spectroscopy can quantify damage after TBI, and NAA levels may be a sensitive indicator of the neuronal damage that results in a worse clinical outcome.  相似文献   
65.
Background: Remifentanil hydrochloride is an ultra-short-acting, esterase-metabolized micro-opioid receptor agonist. This study compared the use of remifentanil or fentanyl during elective supratentorial craniotomy for space-occupying lesions.

Methods: Sixty-three adults gave written informed consent for this prospective, randomized, double-blind, multiple-center trial. Anesthesia was induced with thiopental, pancuronium, nitrous oxide/oxygen, and fentanyl (n = 32; 2 micro gram [center dot] kg [center dot] sup -1 min sup -1) or remifentanil (n = 31; 1 micro [center dot] kg sup -1 [center dot] min sup -1). After tracheal intubation, infusion rates were reduced to 0.03 micro gram [center dot] kg sup -1 [center dot] min sup -1 (fentanyl) or 0.2 micro gram [center dot] kg sup -1 [center dot] min sup -1 (remifentanil) and then adjusted to maintain anesthesia and stable hemodynamics. Isoflurane was given only after specified infusion rate increases had occurred. At the time of the first burr hole, intracranial pressure was measured in a subset of patients. At bone flap replacement either saline (fentanyl group) or remifentanil ([nearly equal] 0.2 micro gram [center dot] kg sup -1 [center dot] min sup -1) were infused until dressing completion. Hemodynamics and time to recovery were monitored for 60 min. Analgesic requirements and nausea and vomiting were observed for 24 h. Neurological examinations were performed before operation and on postoperative days 1 and 7.

Results: Induction hemodynamics were similar. Systolic blood pressure was greater in the patients receiving fentanyl after tracheal intubation (fentanyl = 127 +/- 18 mmHg; remifentanil = 113 +/- 18 mmHg; P = 0.004). Intracranial pressure (fentanyl = 14 +/- 13 mmHg; remifentanil = 13 +/- 10 mmHg) and cerebral perfusion pressure (fentanyl = 76 +/- 19 mmHg; remifentanil = 78 +/- 14 mmHg) were similar. Isoflurane use was greater in the patients who received fentanyl. Median time to tracheal extubation was similar (fentanyl = 4 min: range = -1 to 40 min; remifentanil = 5 min: range = 1 to 15 min). Seven patients receiving fentanyl and none receiving remifentanil required naloxone. Postoperative systolic blood pressure was greater (fentanyl = 134 +/- 16 mmHg; remifentanil = 147 +/- 15 mmHg; P = 0.001) and analgesics were required earlier in patients receiving remifentanil. Incidences of nausea and vomiting were similar.  相似文献   

66.
67.
1. 13,460 men, or about 80 per cent of the entire camp strength, were vaccinated against pneumonia with pneumococcus lipovaccine. 2. The dosage employed in all cases was 1 cc. of the lipovaccine containing approximately 10 billion each of Pneumococcus Types I, II, and III. 3. Both the local and general reactions produced by the vaccine were usually mild. Only 0.7 per cent of those who received the vaccine were sufficiently affected to need hospital care. None of these was seriously ill, and a majority of them returned to duty on the 2nd or 3rd day after admission. 4. Most of the troops inoculated were under observation for 2 or 3 months after vaccination. During this period there were 32 cases of Pneumococcus Type I, II, and III pneumonia among the vaccinated four-fifths of camp, and 42 cases of pneumonia of these types among the unvaccinated one-fifth of camp. If, however, all cases of pneumonia that developed within 1 week after vaccination are excluded from the vaccinated group, there remain only 8 cases of pneumonia produced by fixed types, and these were all secondary to severe attacks of influenza. This exclusion is justified by the fact that protective bodies do not begin to appear in the serum until the 8th day after injection of pneumococcus lipovaccine. 5. There is no evidence whatever that pneumococcus vaccine predisposes the individual even temporarily toward either pneumococcus or streptococcus pneumonia. 6. The weekly incidence rate for pneumonia (all types) among the vaccinated troops was conspicuously lower than that for the unvaccinated troops. 7. The pneumonia incidence rate per 1,000 men during the period of the experiment was twice as high for unvaccinated recruits as for vaccinated recruits, and nearly seven times as high for unvaccinated seasoned men as for vaccinated seasoned men. 8. Influenza causes a marked reduction in resistance to pneumonia even among vaccinated men. Of the 155 cases of pneumonia (all types) developing 1 week or more after vaccination, 133 were secondary to influenza. 9. The death rate for 155 cases of pneumonia (all types) that developed among vaccinated men 1 week or more after vaccination was only 12.2 per cent, whereas the death rate for 327 cases of all types that occurred among unvaccinated troops was 22.3 per cent. The death rate for primary pneumonia among vaccinated troops was 11.9 per cent. Among unvaccinated, it was 31.8 per cent, almost three times as great. On the other hand, the mortality rate in pneumonia secondary to influenza is about the same for the vaccinated and unvaccinated groups. 10. In conclusion, it must be admitted that the results of pneurnococcus vaccination at Camp Wheeler have not been so striking as those obtained at Camp Upton in 1918, largely on account of the influenza epidemic; but, although influenza obscured to some extent the effect of pneumococcus vaccination at Camp Wheeler, the results are sufficiently encouraging to justify its further application in civil as well as in military life.  相似文献   
68.
A necrotic liver abscess model was studied with magnetic resonance (MR) imaging at 1.5 T before and after intravenous administration of gadoteridol at doses of 0.1, 0.25, and 0.5 mmol/kg in 24 rabbits. Enhancement characteristics and lesion delineation were assessed with both breath-hold and non-breath-hold imaging techniques. Lesion delineation, as assessed both by signal intensity measurements and evaluations by two image readers blinded to imaging technique, was greatest on high-dose (0.5 mmol/kg) breath-hold images. Lesion rim enhancement was seen consistently only on postcontrast images obtained at a dose of 0.5 mmol/kg and progressed with time after injection of contrast material.  相似文献   
69.
70.
Mucosal immunity and tolerance: relevance to vaccine development   总被引:17,自引:0,他引:17  
Summary: The mucosal immune system of mammals consists of an integrated network of lymphoid cells which work in concert with innate host factors to promote host defense. Major mucosal effector immune mechanisms include secretory antibodies, largely of immunoglobulin A (IgA) isotype, cytotoxic T cells, as well as cytokines, chemokines and their receptors. Immunologic unresponsiveness (tolerance) is a key feature of the mucosal immune system, and deliberate vaccination or natural immunization by a mucosal route can effectively induce immune suppression. The diverse compartments located in the aerodigestive and genitourinary tracts and exocrine glands communicate via preferential homing of lymphocytes and antigen-presenting cells. Mucosal administration of antigens may result in the concomitant expression of secretory immunoglobulin A (S-IgA) antibody responses in various mucosal tissues and secretions, and under certain conditions, in the suppression of immune responses. Thus, developing formulations based on efficient delivery of selected anti-gens/tolerogens, cytokines and adjuvants may impact on the design of future vaccines and of specific immunotherapeutic approaches against diseases associated with untoward immune responses, such as autoimmune disorders, allergic reactions, and tissue-damaging inflammatory reactions triggered by persistent microorganisms.  相似文献   
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