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81.
CT evaluation of complications of abdominal aortic surgery 总被引:5,自引:0,他引:5
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We present the case of a 3-year-old boy with post-natal growth failure, microcephaly, developmental delay, facial dysmorphism, an evolving pigmentary retinopathy, pituitary hypoplasia, micropenis, and growth hormone (GH) deficiency. He has a microcephalic osteodysplastic slender-bone disorder with disharmonic delayed osseous maturation, most closely resembling patients with microcephalic osteodysplastic primordial dwarfism type II (MOPD II). Intrauterine growth retardation, a universal finding in the MOPD II, was absent in our patient. 相似文献
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Furler SM Poynten AM Kriketos AD Lowy AJ Ellis BA Maclean EL Courtenay BG Kraegen EW Campbell LV Chisholm DJ 《Obesity research》2001,9(9):535-543
OBJECTIVE: Insulin resistance is closely associated with two disparate aspects of lipid storage: the intracellular lipid content of skeletal muscle and the magnitude of central adipose beds. Our aim was to determine their relative contribution to impaired insulin action. RESEARCH METHODS AND PROCEDURES: Eighteen older (56 to 75 years of age) men were studied before elective knee surgery. Insulin sensitivity (M/Delta I) was determined by hyperinsulinemic-euglycemic clamp. Central abdominal fat (CF) was assessed by DXA. Skeletal muscle was excised at surgery and assayed for content of metabolically active long-chain acyl-CoA esters (LCAC). RESULTS: Significant inverse relationships were observed between LCAC and M/Delta I (R(2) = 0.34, p = 0.01) and between CF and M/Delta I (R(2) = 0.38, p = 0.006), but not between CF and LCAC (R(2) = 0.0005, p = 0.93). In a multiple regression model (R(2) = 0.71, p < 0.0001), both CF (p = 0.0006) and LCAC (p = 0.0009) were independent statistical predictors of M/Delta I. Leptin levels correlated inversely with M/Delta I (R(2) = 0.60, p = 0.0002) and positively with central (R(2) = 0.41, p = 0.006) and total body fat (R(2) = 0.63, p = 0.0001). DISCUSSION: The mechanisms by which altered lipid metabolism in skeletal muscle influences insulin action may not be related directly to those linking central fat and insulin sensitivity. In particular, it is unlikely that muscle accumulation of lipids directly derived from labile central fat depots is a principal contributor to peripheral insulin resistance. Instead, our results imply that circulating factors, other than nonesterified fatty acids or triglyceride, mediate between central fat depots and skeletal muscle tissue. Leptin was not exclusively associated with central fat, but other factors, secreted specifically from central fat cells, could modulate muscle insulin sensitivity. 相似文献
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Lieberman G Buscombe JR Hilson AJ Reid WM Thakrar D Maclean AB 《American journal of obstetrics and gynecology》2000,183(3):534-540
OBJECTIVE: This study was undertaken to determine whether preoperative radioimmunoscintigraphy of complex ovarian masses with technetium Tc 99m MAb-170 (Tru-Scint AD; Biomira Inc, Edmonton, Alberta, Canada), a murine whole immunoglobulin G monoclonal antibody that has been found to have panadenocarcinoma affinity, would predict surgical findings. STUDY DESIGN: The age range of studied patients was 42 to 83 years (mean, 60.3 years). Planar computed tomographic imaging and single-photon emission computed tomographic imaging were performed at 15 minutes, 6 to 8 hours, and 18 to 24 hours after injection of 1000 MBq technetium Tc 99m MAb-170. Laparotomy was performed within 10 days. RESULTS: Eighteen patients had borderline or invasive ovarian cancers verified by histologic examination. All primary malignancies or deposits (including intrahepatic deposits) yielded positive results on radioimmunoscintigraphic imaging. Radioimmunoscintigraphy was able to identify serosal deposits not seen on computed tomographic or ultrasonographic scans. False-positive localization of the antibody was noted in 6 of the 9 patients with benign pathologic processes. CONCLUSION: It is possible to detect with technetium Tc 99m MAb-170 all patients who have cancer (including sites not seen on computed tomographic or ultrasonographic scan); however, the low specificity (33%) means that patients still require surgical verification of disease. 相似文献
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Introduction: Increased stress levels have been reported and it has been implicated for mental illness amongst service personnel. However no study has been reported among Indian naval sailors. 相似文献
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M. M. Szczesniak R. B. H. Williams H. M. Brake J. C. Maclean I. E. Cole I. J. Cook 《Neurogastroenterology and motility》2010,22(4):381-e89
Background Inappropriate or excessive, non‐swallow related, reflexive relaxation of the upper esophageal sphincter (UES) in response to esophageal distension may be the principal mechanism permitting retrograde trans‐sphincteric flow during acid regurgitation. The neural pathways mediating reflexive UES relaxation in the human have received little attention. Patients with laryngitis demonstrate an increased acid reflux in the proximal esophagus. Such events, combined with an increased tendency for UES relaxation, might precipitate regurgitation into the pharynx. The aim was to determine whether the esophago‐UES relaxation reflex induced by rapid esophageal distension is upregulated in patients with posterior laryngitis. Methods In 21 healthy volunteers and 14 patients with posterior laryngitis, UES responses to rapid air insufflation were examined. UES responses were monitored with perfused manometry catheter with a oval sleeve sensor. Key Results The probability of triggering UES relaxation in response to the rapid esophageal air distension, for all volumes of insufflation, was higher in laryngitis (45%) than in health (17%). The minimum distension volume required to elicit an UES relaxation response was significantly lower in laryngitis patients when compared with controls. Patients who demonstrated a laryngoscopic response to a trial of omeprazole, were less likely to generate a distension‐induced UES contractile response (5%) than patients who did not respond (23%). Conclusions & Inferences The threshold for esophageal distension‐induced UES relaxation is reduced in patients with laryngitis when compared with controls. This finding supports the hypothesis that in this population, a hypersensitive belch‐like response may be one contributory mechanism of regurgitation when triggered by an abrupt spontaneous gastro‐esophageal reflux event. 相似文献
90.
The effect of a central fusion lock on forced vergence fixation disparity curve parameters, that is, magnitudes of fixation disparity and associated phoria, curve type and the central slope of the curve, was studied in 84 subjects because of ambiguity in the previous studies. It was found that the magnitudes of exo fixation disparity and exo associated phoria decreased significantly when they were measured with the central fusion lock. The central lock had no noticeable effect on the type of the curve, although, the central slope of the curve was flatter in the presence of the central lock. 相似文献