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61.
We are grateful to Dr Parmar for raising this important issue.Dr Parmar appears to be under the impression that our studysample consisted of elderly men with hypertension.  相似文献   
62.
Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm−5) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH2O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH2O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion.  相似文献   
63.
64.
BACKGROUND CONTEXT: Methylprednisolone has evolved during the 1990s, through the results obtained from the National Acute Spinal Cord Injury Studies NASCIS II and III, as a standard treatment in acute spinal injury. PURPOSE: To evaluate the scientific basic for the use of methylprednisolone in acute spinal cord injury. STUDY DESIGN: Systematic review of the accumulated literature. METHODS: Critical evaluation of the data obtained in the NASCIS II and III studies plus other accumulated literature. RESULTS: Analyses have been made on subgroups of the study populations, and the results were based on statistical artefacts. Furthermore, improved functional recovery shown by these studies was not clinically significant. CONCLUSION: There is insufficient evidence to support the use of methylprednisolone as a standard treatment in acute spinal cord injury.  相似文献   
65.
The purpose of this study was to evaluate an instrument for assessment of physical disability, mainly intended for clinical settings, the Disability Rating Index (DRI). Healthy persons (n = 1092), both white and blue collar workers, and patients (n = 366) with different levels of physical capacity, were assessed. Most of the patients (n = 303) underwent rehabilitation programmes for neck/shoulder/low-back pain but some (n = 47) were arthritis patients waiting for hip or knee replacement surgery, or wheelchair patients with multiple sclerosis (n = 16). The reliability was investigated by test-retest studies, intra- and inter-rater and internal consistency studies. Five construct validity tests were carried out: a discrimination study; a converging validity test; a test for sensitivity to small alterations in health status; and two correlational validity tests. Correlation of the self-reported DRI to the actual performance in similar activities was carried out. Responsiveness was tested by correlation of the DRI before/after replacement surgery for arthritis. The test-retest correlations were 0.83–0.95 in the studies, including correlation of different versions. The intra- and inter-rater reproducibility was 0.98 and 0.99 respectively. The Kruskal-Wallis test in the discrimination study yielded p < 0.0001. More than 90% of the respondents completed the questionnaire correctly. Correlation of the DRI to the Functional Status Questionnaire was 0.46. The responsiveness was excellent, p = 0.0001. The DRI proved to be a robust, practical clinical and research instrument with good responsiveness and acceptability for assessment of disability caused by impairment of common motor functions.  相似文献   
66.
OBJECTIVE: To compare effectiveness of two techniques for removing football face masks: cutting loop straps [cutting tool: FMXtractor (FMX)] or removing screws with a cordless screwdriver and using the FMXtractor as needed for failed removals [combined tool (CT)]. Null hypotheses: no differences in face mask removal success, removal time or difficulty between techniques or helmet characteristics. DESIGN: Retrospective, cross-sectional. SETTING: NOCSAE-certified helmet reconditioning plants. PARTICIPANTS: 600 used high school helmets. INTERVENTIONS: Face mask removal attempted with two techniques. MAIN OUTCOME MEASUREMENTS: Success, removal time, rating of perceived exertion (RPE). RESULTS: Both techniques were effective [CT 100% (300/300); FMX 99.4% (298/300)]. Use of the backup FMXtractor in CT trials was required in 19% of trials. There was significantly (P<0.001) less call for the backup tool in helmets with silver screws (6%) than in helmets with other screws (31%). Mean removal time was 44.51+/-18.79s (CT: 37.84+/-15.37s, FMX: 51.21+/-19.54s; P<0.001). RPE was different between techniques (CT: 1.83+/-1.20, FMX: 3.11+/-1.27; P<0.001). Removal from helmets with silver screws was faster (Silver=33.38+/-11.03, Others=42.18+/-17.64; P<0.001) and easier (Silver=1.42+/-0.89, Other=2.23+/-1.33; P<0.001). CONCLUSIONS: CT was faster and easier than FMX. Most CT trials were completed with the screwdriver alone; helmets with silver screws had 94% screwdriver success. Clinically, these findings are important because this and other research shows that compared to removal with cutting tools, screwdriver removal decreases time, difficulty and helmet movement (reducing potential for iatrogenic injury). The combined-tool approach captures benefits of the screwdriver while offering a contingency for screw removal failure. Teams should use degradation-resistant screws. CLINICAL RELEVANCE: Sports medicine professionals must be prepared with appropriate tools and techniques to efficiently remove the face mask from an injured football player's helmet.  相似文献   
67.
A set-up for D.C. recordings of slow ocular potentials such as the c-wave of the electroretinogram (ERG) as well as the fast oscillation (FO), the light peak (LP) and the dark trough (DT) in both clinical and experimental work is described. It includes matched calomel half-cells connected by saline-agar bridges to a corneal contact lens on the eye and a reference chamber on the forehead, a low-drift differential-input D.C. amplifier, an A/D converter, a computer, a thermoprinter, a flexible disc memory, a plotter, and a device for light stimulation controlled by the computer.Examples of the usefulness of the set-up in clinical work are shown in the form of D.C. c-wave ERGs of normal subjects as well as of patients with vitelliform macular degeneration, choriocapillaris atrophy, and retinitis pigmentosa. The direct corneal recording of the FO and LP is demonstrated as well. The different origins of the standing potential (SP) of the eye, the ERG c-wave, the FO and the LP are reviewed briefly.  相似文献   
68.
The planar fibrous connective tissues of the body are composed of a dense extracellular network of collagen and elastin fibers embedded in a ground matrix, and thus can be thought of as biocomposites. Thus, the quantification of fiber architecture is an important step in developing an understanding of the mechanics of planar tissues in health and disease. We have used small angle light scattering (SALS) to map the gross fiber orientation of several soft membrane connective tissues. However, the device and analysis methods used in these studies required extensive manual intervention and were unsuitable for largescale fiber architectural mapping studies. We have developed an improved SALS device that allows for rapid data acquisition, automated high spatial resolution specimen positioning, and new analysis methods suitable for large-scale mapping studies. Extensive validation experiments revealed that the SALS device can accurately measure fiber orientation for up to a tissue thickness of at least 500 μm to an angular resolution of∼1o and a spatial resolution of±254 μm. To demonstrate the new device’s capabilities, structural measurements from porcine aortic valve leaflets are presented. Results indicate that the new SALS device provides an accurate method for rapid quantification of the gross fiber structure of planar connective tissues.  相似文献   
69.
We assessed the prevalence of Parkinson's disease in Cantalejo, Spain. In 1994, we screened 1,579 persons (age > or = 40 years) using a high-sensitivity method. Cases fulfilling established clinical criteria were followed for a minimum of 3 years. Prevalences were compared with those from other door-to-door surveys. We detected 27 individuals with parkinsonism, 20 of whom had Parkinson's disease. The prevalence of Parkinson's disease increased with age and, when age-adjusted to European standards, was 9.01 per 1,000 (age 40 years and over; 10.78 in men and 5.23 in women). Of the 11 men, three were in Hoehn & Yahr grades III-IV, but six of the nine women were more severely affected. Overall, we found 18 newly diagnosed cases of parkinsonism, 13 of which were Parkinson's disease, and the majority of which were in men aged 80 years or older with a mean duration of illness of 5 years. Our prevalence figures are the highest reported, apparently because of the inclusion of several very elderly men. Parkinson's disease in Cantalejo is less severe in men than in women, particularly in those newly diagnosed. Despite the low numbers, the high prevalence and sex-related pattern are unexplained but they probably relate to the high sensitivity of the screening method.  相似文献   
70.
OBJECTIVE: The combination of mifepristone and misoprostol is an established method for induction of early first trimester abortion, but there is no consensus about the best evaluation of treatment outcome. We assessed endometrial thickness, determined by ultrasound and serum-human chorionic gonadotropin (s-hCG) as markers of successful management. METHODS: Prospective trial involving 255 women, with a gestation of 62 days or less, who were to undergo medical abortion. In addition to our established routines of performing clinical and ultrasound examinations, we also determined the s-hCG level prior to treatment and at follow-up. RESULTS: Of the 255 subjects treated during the study, 20 (7.8%) were lost to follow-up. The overall complete abortion rate was 94.0%. Fourteen subjects required vacuum aspiration, nine of them prior to the scheduled follow-up and five thereafter. None of the pregnancies were ongoing. A decrease of 99% in s-hCG levels was noted in 99% of the women, when levels determined prior to mifepristone intake and those measured 15-71 days post-abortion were compared. CONCLUSION: This study confirms that s-hCG levels drop sharply after medical abortion. To assess the completeness of medical abortion, we recommend that clinical examination to be combined with determination of s-hCG. Ultrasonography should be carried out only when indicated.  相似文献   
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