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951.
We have undertaken a prospective study of the presentation of all 669 ulcers seen in a specialist multidisciplinary foot clinic between 1 January 1993 and 1 August 1996, with particular reference to the factors which precipitated ulceration as well as to any delays in referral. Nearly two-thirds (61.3%) of all lesions were first detected by the patient or a relative, and the remainder by a healthcare professional. The median (range) time which elapsed between ulcer onset and first professional review was 4 (0-247) days, and the median time between first review and first referral to the specialist clinic was 15 (0-608) days. Significant delays were judged to have occurred in 39 instances. The most common precipitant of ulceration was rubbing from footwear, which was responsible for 138 (20.6%). Fifty-eight (8.7%) were the result of immobilization from other illness, and a further 24 were the consequence of surgery. Overall, professional factors contributed to the development or deterioration of 106 lesions (15.8% total). These results should form the basis of strategies designed to minimize the onset of ulceration in those known to be at risk: educational strategies need to be directed at professionals as much as at patients.  相似文献   
952.
Prior studies in CD4-deficient mice established the capacity of T helper (Th) lineage cells to mature into Th1 cells. Unexpectedly, challenge of these mice with Nippostrongylus brasiliensis, a Th2-inducing stimulus, failed to result in the development of Th2 cells. Additional studies were performed using CD4+ or CD4-CD8- (double-negative) T cell receptor (TCR) transgenic T cells reactive to LACK antigen of Leishmania major. Double-negative T cells were unable to develop into Th2 cells in vivo, and, unlike CD4+ T cells, could not be primed for interleukin-4 production in vitro. Similarly, CD4+ TCR transgenic T cells primed on antigen-presenting cells expressing mutant MHC class II molecules unable to bind CD4 did not differentiate into Th2 cells. These data suggest that interactions between the TCR, MHC II-peptide complex and CD4 may be involved in Th2 development.  相似文献   
953.
The aim of this study was to measure the production of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) by alveolar macrophages in patients with rheumatoid arthritis and interstitial lung disease (ILD). Rheumatoid arthritis patients diagnosed by ACR criteria (n = 8) with associated ILD documented by pulmonary function tests and high resolution computerized tomography scanning, and 12 healthy volunteers (6 smokers and 6 nonsmokers). We determined the spontaneous and induced production of bacterial lipopolysaccharides (LSP), TNF-alpha and IL-6 by alveolar macrophages obtained by bronchoalveolar lavage. The macrophages were isolated by Ficoll-Hypaque gradient centrifugation and plastic adherence and cultured in serum-containing medium (low endotoxin) in the presence and absence of LPS (100 ng/ml). TNF-alpha and IL-6 levels contents were determined in supernatants by ELISA. In the patient group both spontaneous and induced production of TNF-alpha were significantly higher than in controls (p < 0.01). Macrophages stimulated with LPS in patients with rheumatoid arthritis and ILD also released greater amounts of IL-6 than did those of the healthy controls. IL-6 spontaneous and induced production was significantly lower in smokers than in nonsmokers. TNF-alpha and IL-6 production in patients with rheumatoid arthritis and ILD, studied in bronchoalveolar lavage specimens reveals that alveolar macrophages are hyperreactive in these patients, who are possibly sensitized as a consequence of the inflammatory lung process inherent to the disease. Further study is needed to define the pathogenic role of these mediators.  相似文献   
954.
The authors report a case of presumed idiopathic chronic iridocyclitis in which an intraocular foreign body (IOFB) was finally identified. There was no history of prior eye trauma. Ophthalmologic and laboratory evaluations were inconclusive. Seven months following unsuccessful medical treatment of the iritis and given the patient's occupational history, a skull x-ray was performed followed by computed tomography of the orbits. A metallic IOFB was identified in the pars plicata and was surgically removed with resolution of the inflammation. The possibility of an IOFB should always be entertained in idiopathic iridocyclitis refractory to medical treatment, even when there is no history of ocular trauma.  相似文献   
955.
956.
Visceral pain is a substantial, clinical problem but unfortunately few experimental models are available to study this phenomenon in man. In the present study we inserted a stimulation catheter 5-10 cm into the ileo-sigmoidostomy of nine patients. The catheter contained six small, flexible electrodes separated by 4 mm. The gut was stimulated by single burst, repeated burst (five stimuli delivered at 2 Hz), or continuous burst stimuli (4 Hz for 30, 60, 90, and 120 s). The sensation (ST), pain detection (PDT), and pain tolerance (PTT) thresholds to single/repeated burst stimuli were determined. The location/size/sensitivity of referred pain after repeated/continuous stimulation were characterized. The brain potentials to single burst stimuli and to increasing stimulus intensity were measured. ST to single burst stimuli was easy to determine (8 mA) and to reproduce. The patients found it difficult to determine the PDT and PTT to single burst stimuli, however both thresholds were easily determined for repeated burst stimuli. The pain thresholds to single burst stimuli were twice as high as the thresholds to repeated burst stimuli, indicating the importance of central temporal summation for visceral pain. Minor changes in the stimulus location resulted in changes of the referred pain projection site. The words most frequently selected (78%) from the McGill Pain Questionnaire to describe repeated burst stimulations were shooting, pricking, flashing, and boring. The amplitude of the brain potentials increased at increasing stimulus intensity. A stimulus intensity giving an initial pain rating of around 5 on a 0-10 visual analog scale (VAS) was used for continuous stimulation. A general increase of the pain intensity and the area of referred pain was found during this stimulation. It was concluded that electrical stimulation of the human gut provokes pain and especially long sequences of visceral stimuli are adequate to evoke referred pain mimicking pain profiles of pathologic origin.  相似文献   
957.
Enthesitis occurs commonly in patients with seronegative spondyloarthropathies. The patella is frequently affected by enthesopathy, but overgrowth has not been reported as a manifestation of enthesitis in pediatrics. We describe 3 patients with seronegative enthesopathy and arthropathy syndrome and patellar overgrowth.  相似文献   
958.
We studied the incidence and severity of supine hypertension in 117 patients with severe primary autonomic failure presenting to a referral center over a 9-year period. Patients were uniformly characterized by disabling orthostatic hypotension, lack of compensatory heart rate increase, abnormal autonomic function tests, and unresponsive plasma norepinephrine. Fifty-four patients had isolated autonomic impairment (pure autonomic failure). Sixty-three patients had central nervous system involvement in addition to autonomic impairment (multiple-system atrophy). Patients were studied off medications, in a metabolic ward, and on a controlled diet containing 150 mEq of sodium. Fifty-six percent of patients had supine diastolic blood pressure > or =90 mm Hg. The prevalence of hypertension was slightly greater in females (63%) than in males (52%). Potential mechanisms responsible for this hypertension were investigated. No correlation was found between blood volume and blood pressure. Similarly, plasma norepinephrine (92+/-15 pg/mL) and plasma renin activity (0.3+/-0.05 ng/mL per hour) were very low in the subset of patients with pure autonomic failure and supine hypertension (mean systolic/diastolic pressure, 177 +/- 6/108 +/- 2 mm Hg, range 167/97 to 219/121). Supine hypertension represents a challenge in the treatment of orthostatic hypotension. We found these patients to be particularly responsive to the hypotensive effects of transdermal nitroglycerin. Doses ranging from 0.025 to 0.1 mg/h decreased systolic blood pressure by 36+/-7 mm Hg and may effectively treat supine hypertension overnight, but the dose should be individualized and used with caution.  相似文献   
959.
Growth hormone receptor (GHR) has a major role in the regulation of growth hormone action, and thus, is an obvious candidate gene associated with milk production traits in mammals. The present authors have sequenced 273 bp of the 3' flanking region of the bovine GHR, and found three length variants and one base substitution polymorphism in this region. Allele frequencies of the length variants differ between Finnish native and commercial dairy cattle breeds. The chromosomal localization of GHR was confirmed to bovine chromosome 20 by synteny mapping and linkage analysis.  相似文献   
960.
STUDY OBJECTIVES: To determine whether the quantitative evaluation of hemomediastinum using transesophageal echocardiography (TEE) is predictive of the presence of a traumatic disruption of the thoracic aorta (TDA) or its branches in patients who have sustained severe blunt chest trauma. DESIGN: Retrospective study. SETTING: ICU of a tertiary referral teaching hospital. PATIENTS: Forty-one patients sustaining severe blunt chest trauma (32 men, nine women; mean age, 43+/-16 years; mean Injury Severity Score, 39+/-22) who underwent a TEE study were divided into two groups, patients with (group TDA+, n=15) or without (group TDA-, n=26) major vascular injury diagnosed using an alternative method such as aortography, surgery, or necropsy. The control group included 41 age- and sex-matched patients with an unremarkable TEE study performed to rule out an intracardiac source of emboli. INTERVENTIONS: The presence of hemomediastinum was quantitatively assessed by measuring the distances between the esophageal scope and anteromedial aortic wall (distance 1), and between the posterolateral aortic wall and left visceral pleura (distance 2) at the level of the aortic isthmus. An observer who was unaware of both medical history and final diagnosis measured the distances. MEASUREMENTS AND RESULTS: In group TDA+, TEE demonstrated aortic injuries in 13 patients, revealed an isolated hemomediastinum in one patient (ruptured intercostal arteries), and was unremarkable in the remaining patient, who sustained a disrupted right subclavian artery. No associated major vessel injuries were diagnosed in the group TDA- (normal aortograms). When compared to the control group, mean distances were greater in patients with chest trauma (distance 1=5.5+/-4.4 mm vs 2.7+/-0.8 mm, p=0.001; distance 2=3.8+/-5.0 mm vs 1.2+/-0.3 mm, p=0.02). The corresponding distances were even greater in group TDA+ when compared with group TDA- (distance 1=8.6+/-5.9 mm vs 3.7+/-1.5 mm, and distance 2=7.1+/-7.0 mm vs 2.0+/-1.7; for both differences, p<0.01). A threshold value of 5.5 mm for distance 1 or 6.6 mm for distance 2 had a sensitivity of 80%, a specificity of 92%, a positive and negative predictive value of 86% and 89%, respectively, for the diagnosis of underlying major vascular injury. CONCLUSIONS: TEE allows quantitative assessment of traumatic hemomediastinum. The presence of a large hemomediastinum requires further evaluation by aortography, even if the thoracic aorta appears normal during the TEE examination, in order to rule out an underlying major vascular injury which may be outside the field of view of the echocardiographer.  相似文献   
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