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31.
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Margherita Mascolo MD Elizabeth Dee MD Ronald Townsend MD John T. Brinton PhD Philip S. Mehler MD FACP FAED 《The International journal of eating disorders》2015,48(5):532-534
Forty‐seven year old female, with a history of anorexia nervosa, was admitted to a medical stabilization unit (ACUTE) complaining of abdominal pain exacerbated by oral intake, associated with nausea, and relieved by emesis. Admission body mass index was 10.6. Labs were notable for hepatitis and hypoglycemia. On her progressive oral refeeding plan, she suddenly developed severe abdominal pain. Computed tomography (CT) revealed gastric dilatation and superior mesenteric artery (SMA) syndrome. SMA syndrome is a rare complication of severe malnutrition resulting from compression of the duodenum between the aorta and the SMA. It is diagnosed by an upper gastrointestinal series or an abdominal CT. Gastric dilatation, in turn, is a rare complication of SMA syndrome to be included in the differential diagnoses of abdominal pain in severely malnourished patients as it is potentially life‐threatening. The patient was switched to an oral liquid diet, began weight restoring, and had resolution of symptoms. © 2015 Wiley Periodicals, Inc. (Int J Eat Disord 2015; 48:532–534) 相似文献
33.
Radioimmunoassays that detect specifically peptide sequences within either the biologically active amino region (N-assay) or inactive carboxyl region (C-assay) of parathyroid hormone (PTH) were used to evaluate the metabolism of PTH during and after infusion and injection of homogeneous (containing less than 0.1% hormonal fragments) intact bovine PTH (bPTH) into calves. During continuous infusions of hormone, when constant blood levels of immunoreactive PTH were reached, a dissociation between the concentrations of amino versus carboxyl immunoreactivity was observed; concentrations of hormone measured by the C-assay rose to a level of approximately three times higher than that measured by the N-assay. Analysis by gel filtration of immunoreactive PTH in plasma samples from calves after injection of hormone showed the rapid disappearance of intact hormone (N- and C-assays) and the appearance of a large fragment detected by the C-assay but not by the N-assay. The hormonal fragment lacked antigenic determinants within the amino peptide sequence required for biologic activity. No additional fragments of PTH were detected by gel filtration using the N- and C-assays. No detectable conversion of intact PTH to hormonal fragments occurred during incubation in vitro in bovine serum. The results are consistent with the concept that PTH is metabolized after entry into the circulation at peripheral sites located outside the vascular space, resulting in the rapid disappearance from blood of intact hormone and the appearance of a biologically inactive hormonal fragment(s). These studies done in calves agree with earlier studies done in dogs and man and point to the existence in mammals of common pathways for the peripheral metabolism of PTH. 相似文献
34.
Dugan VG Varela AS Stallknecht DE Hurd CC Little SE 《Vector borne and zoonotic diseases (Larchmont, N.Y.)》2004,4(2):131-136
Although white-tailed deer (WTD; Odocoileus virginianus ) are considered the primary natural reservoir host for Ehrlichia chaffeensis, the causative agent of human monocytotropic ehrlichiosis, the potential role of other vertebrates as reservoir hosts has not been fully explored. Because domestic goats are naturally infected in areas where E. chaffeensis is endemic in deer, we evaluated the susceptibility of domestic goats to experimental infection with E. chaffeensis. A total of 12 goats were inoculated with E. chaffeensis (15B-WTD-GA or Ark strain)-infected DH82 cells by one of three routes: intravenously, subcutaneously, or intradermally. White-tailed deer simultaneously inoculated with the same dose, route, and inoculum served as positive controls; additional goats and WTD were included as negative controls. Evidence of E. chaffeensis infection was evaluated in all animals by indirect fluorescent antibody assay, PCR, and cell culture isolation techniques. All goats exposed to E. chaffeensis seroconverted by 14 days post-infection (DPI), and E. chaffeensis was isolated from one goat on 3 DPI; however, molecular or cell culture evidence of active infection was not detected in goats later than 3 DPI. White-tailed deer exhibited serologic and molecular evidence of E. chaffeensis infection throughout both trials, and E. chaffeensis was reisolated in cell culture from all infected WTD on numerous days post-infection. Our results suggest that despite the occurrence of natural infection in goats, this animal may not be susceptible to experimental infection and thus may not serve as a suitable model of E. chaffeensis reservoir host infection. 相似文献
35.
36.
Drug-induced haemolytic anaemia can be life threatening. We report a case of ceftriaxone-induced severe haemolytic anaemia in a previously healthy 68-year-old woman. The patient had a positive direct antiglobulin test (anti-C3d positive, anti-immunoglobulin G negative). Serological tests showed ceftriaxone-specific antibodies. The patient recovered after cessation of the drug. This complication may cause milder anaemia and thus be poorly recognized. 相似文献
37.
Spinal cord injury and protection 总被引:5,自引:0,他引:5
D K Anderson P Demediuk R D Saunders L L Dugan E D Means L A Horrocks 《Annals of emergency medicine》1985,14(8):816-821
Subsequent to traumatic injury of the spinal cord, a series of pathophysiological events occurs in the injured tissue that leads to tissue destruction and paraplegia. These include hemorrhagic necrosis, ischemia, edema, inflammation, neuronophagia, loss of Ca2+ from the extracellular space, and loss of K+ from the intracellular space. In addition, there is trauma-initiated lipid peroxidation and hydrolysis in cellular membranes. Both lipid peroxidation and hydrolysis can damage cells directly; hydrolysis also results in the formation of the biologically active prostaglandins and leukotrienes (eicosanoids). The time course of membrane lipid alterations seen in studies of antioxidant interventions suggests that posttraumatic ischemia, edema, inflammation, and ionic fluxes are the result of extensive membrane peroxidative reactions and lipolysis that produce vasoactive and chemotactic eicosanoids. A diverse group of compounds has been shown to be effective in ameliorating spinal cord injury in experimental animals. These include the synthetic glucocorticoid methylprednisolone sodium succinate (MPSS); the antioxidants vitamin E, selenium, and dimethyl sulfoxide (DMSO); the opiate antagonist naloxone; and thyrotropin-releasing hormone (TRH). With the exception of TRH, all of these agents have demonstrable antioxidant and/or anti-lipid-hydrolysis properties. Thus the effectiveness of these substances may lie in their ability to quench membrane peroxidative reactions or to inhibit the release of fatty acids from membrane phospholipids, or both. Whatever the mode of action, early administration appears to be a requirement for maximum effectiveness. 相似文献
38.
AbstractGlyoxal is a popular substitute for formalin and in many ways acts like it, although there are significant differences. When formulated correctly, glyoxal fixatives produce superior morphological detail in only 1-9 h, but crosslinking does not occur. Glyoxal has a unique reactivity with arginine, producing a cyclic imidazole in place of the highly charged guanidinium group, thus reducing eosinophilia in arginine-rich tissue elements. In the absence of crosslink-induced masking of epitopes, most antibodies work directly on glyoxal-fixed specimens without the need for antigen retrieval. The arginine reaction does cause loss of immunoreactivity in arginine-rich antigens, however. Fortunately, the imidazole is readily removed by a simple antigen retrieval process: pH 8.6 Tris HCl buffer for 10 min at 125°C. The conformational basis for needing antigen retrieval, and how it works on a molecular level is explained for both glyoxal and formalin fixation. (The J Histotechnol 29:65, 2006)Submitted November 4, 2005; accepted with revisions March 15, 2006. 相似文献
39.
Andrew D. Choi Dustin M. Thomas James Lee Suhny Abbara Ricardo C. Cury Jonathon A. Leipsic Christopher Maroules Prashant Nagpal Michael L. Steigner Dee Dee Wang Michelle C. Williams Irfan Zeb Todd C. Villines Ron Blankstein 《Journal of Cardiovascular Computed Tomography》2021,15(1):2-15
Cardiovascular computed tomography (CCT) is a well-validated non-invasive imaging tool with an ever-expanding array of applications beyond the assessment of coronary artery disease. These include the evaluation of structural heart diseases, congenital heart diseases, peri-procedural electrophysiology applications, and the functional evaluation of ischemia. This breadth requires a robust and diverse training curriculum to ensure graduates of CCT training programs meet minimum competency standards for independent CCT interpretation. This statement from the Society of Cardiovascular Computed Tomography aims to supplement existing societal training guidelines by providing a curriculum and competency framework to inform the development of a comprehensive, integrated training experience for cardiology and radiology trainees in CCT. 相似文献
40.
Rosiglitazone improves insulin sensitivity and glucose tolerance in subjects with impaired glucose tolerance 总被引:2,自引:0,他引:2
Hung YJ Hsieh CH Pei D Kuo SW Lee JT Wu LY He CT Lee CH Fan SC Sheu WH 《Clinical endocrinology》2005,62(1):85-91
OBJECTIVE: This study was designed to evaluate the effects of rosiglitazone (ROS) on insulin sensitivity, beta-cell function, and glycaemic response to glucose challenge and meal in subjects with impaired glucose tolerance (IGT). METHODS: Thirty patients with IGT (ages between 30 and 75 years and BMI (body mass index) < or = 27 kg/m2) were randomly assigned to receive either placebo (n = 15) or ROS (4 mg/day) (n = 15). All participants underwent a 75-g oral glucose tolerance test (OGTT), meal test, and frequently sampled intravenous glucose tolerance test (FSIGT) before and after the 12-week treatment. RESULTS: After 12 weeks of ROS treatment, there were significant increases in total cholesterol (TC) (4.25 +/- 0.22 vs 4.80 +/- 0.17 mmol/l, P < 0.001), high-density lipoprotein cholesterol (HDL-C) (1.25 +/- 0.07 vs 1.43 +/- 0.06 mmol/l, P < 0.05), and low-density lipoprotein cholesterol (LDL-C) (2.70 +/- 0.15 vs 3.37 +/- 0.17 mmol/l, P < 0.05) without changes in triglyceride concentration, TC/HDL-C and LDL-C/HDL-C ratio. Although the acute insulin response (AIR) to intravenous glucose and disposition index (measured as the ability of pancreatic beta-cell compensation in the presence of insulin resistance) remained unchanged, the insulin sensitivity (SI) and glucose effectiveness (SG) were remarkably elevated (0.38 +/- 0.06 vs 0.54 +/- 0.09 x 10(-5) min(-1)/pmol, P < 0.05; 0.017 +/- 0.002 vs 0.021 +/- 0.001 min(-1), P < 0.05, respectively) in the ROS group. The glucose, insulin, and c-peptide areas under curve (AUC) in response to OGTT and the glucose and insulin AUC during meal were significantly ameliorated in the ROS group. Five out of 15 (33%) and two out of 15 (13%) subjects treated with ROS and placebo, respectively, reversed to normal response during OGTT (P < 0.05). CONCLUSION: Rosiglitazone treatment significantly improved insulin resistance and reduced postchallenge glucose and insulin concentrations in patients with impaired glucose tolerance without remarkable effects on beta-cell secretory function. 相似文献