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51.
18F‐Fluoro‐deoxyglucose positron emission computed tomography (FDG‐PET/CT) is an emerging diagnostic imaging modality in veterinary medicine; however, little published information is available on physiologic variants, benign processes, and artifacts. The purpose of this retrospective study was to describe the number of occurrences of non‐neoplastic disease‐related FDG‐PET/CT lesions in a group of dogs and cats. Archived FDG‐PET/CT scans were retrieved and interpreted based on a consensus opinion of two board‐certified veterinary radiologists. Non‐neoplastic disease‐related lesions were categorized as physiologic variant, benign activity, or equipment/technology related artifact. If the exact cause of hypermetabolic areas could not be determined, lesions were put into an indeterminate category. A total of 106 canine and feline FDG‐PET/CT scans were included in the study. In 104 of the 106 scans, a total of 718 occurrences of physiologic variant, areas of incidental benign activity, and artifacts were identified. Twenty‐two of 23 feline scans and 82 of 83 canine scans had at least one artifact. Previously unreported areas of increased radiopharmaceutical uptake included foci associated with the canine gall bladder, linear uptake along the canine mandible, and focal uptake in the gastrointestinal tract. Benign activity was often seen and related to healing, inflammation, and indwelling implants. Artifacts were most often related to injection or misregistration. Further experience in recognizing the common veterinary FDG physiologic variation, incidental radiopharmaceutical uptake, and artifacts is important to avoid misinterpretation and false‐positive diagnoses. 相似文献
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Katie Woodard Jordan Kraft Shiva Adhikari Daniel Patanroi Bret Crim Randy Berghefer Rodger Main 《Journal of veterinary diagnostic investigation》2021,33(3):410
As client interactions with veterinary diagnostic laboratories have evolved, so have client expectations: faster results, enhanced accessibility to cases, and more seamless data transfer from the laboratory database; all of these factors have encouraged the evolution of diagnostic laboratory systems. This evolution started with 24-h access to laboratory results via the web, yet data quality remained at the mercy of the person filling out the form. If bad (incomplete) information was flowing in, then the data coming out was equally bad (incomplete or inconsistent). By designing a web-based system integrated into our existing reporting platform, the Iowa State University Veterinary Diagnostic Laboratory (ISU-VDL) set out to improve the quality of submission data by including the premises identification number (PIN) and obtaining consistent location data, all while presenting to the client an easy-to-use interface. Efforts continued by incentivizing the use of this tool and client submission practices. As clients transitioned, data have become more complete, resulting in easier queries and an improved ability to leverage the diagnostic data. To further enhance the client experience, a streamlined daily reporting summary was designed to communicate laboratory results succinctly. The use of these web-based tools had a positive impact on the quality and consistency of the diagnostic data. As new ideas develop, the ISU-VDL strives to foster continuous improvement and positively impact the clients’ experience. 相似文献
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A field experiment with winter oilseed rape was conducted near Göttingen (northern Germany) in the growing season 1998–99. Twelve varieties were compared at two nitrogen (N) application rates (0, 206 kg N ha–1) regarding shoot dry matter production, shoot N content, shoot N uptake (beginning of shooting, beginning of flowering), and seed yield. Canopy reflectance was measured one week before the beginning of shooting and one week before flowering at different wavelengths between 550 and 940 nm using a spectral reflectance sensor, type FAL II. The vegetation indices red edge inflection point (RIP), soil adjusted vegetation index (SAVI), and normalized vegetation index (NDVI) introduced in literature as indicators of growth parameters were calculated from the reflectance values and compared with growth parameters. The results showed that the measuring angle (–45° to 45°) had a significant influence on the calculated vegetation indices. Therefore, the measuring angle should be kept constant during the measurements. Nitrogen fertilization led to an increase of all vegetation indices. The results revealed significant differences between the tested varieties, indicating problems regarding an accurate estimation of the N status of the crop. Consistent differences in the vegetation indices appeared between varieties with extremely different growth parameters. However, no general relationship between growth parameters and vegetation indices of the 12 varieties could be found. Therefore, variety‐specific calibrations are necessary. The indices RIP and SAVI resulted in similar statements and seem to be good parameters regarding N effects and variety differences, whereas NDVI could resolve variety differences in the fertilized treatments only imperfectly. 相似文献
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The ICG test is recommended as a replacement for the nowadays rarely performed BSP test. ICG has less side effects, and it has a greater range of use. Extrahepatic influences are of little importance. Disadvantages are the greater cost and extra equipment required, the labile nature of the dye solution and the calculation procedure. Reference ("normal") values of the clearance coefficient are 0.044 to 0.131 min-1 and those for the half life 5.2 to 11.2 min. The test is suitable for information about the secretion of the whole liver and the state of its circulation. 相似文献
57.
Atrial natriuretic peptide (ANP) is stored in atrial myocytes as a 126 amino acid precursor molecule (ANP 1-126) and is cleaved during its release into circulation into the biologically active C-terminal ANP (99-126) and the N-terminal counterpart, ANP (1-98). While interest has focused on ANP (99-126) under physiological and pathophysiological conditions, data for the cosecreted N-terminal sequence, ANP (1-98) are generally missing. Plasma levels of the N-terminal immunoreactive peptide (N-ANP [1-98]) were measured in normal dogs, and in dogs with impaired volume regulation (congestive heart failure; chronic renal failure or Cushing's syndrome and compared with those of C-ANP (99-126). The N-ANP (1-98) concentration was 593.1 +/- 81.1 fmol ml-1 in normal subjects, which is about 60-fold higher than the C-ANP (99-126) (10.8 +/- 2.6 fmol ml-1). In patients suffering from chronic renal failure ANP (1-98) was increased to 1582 +/- 196 fmol ml-1, and in dogs with congestive heart failure to 1612 +/- 244 fmol ml-1. In contrast, Cushing's syndrome dogs showed decreased N-ANP (1-98) concentrations (351 +/- 65.9 fmol ml-1). There was a positive correlation between plasma levels of N-ANP (1-98) and C-ANP (99-126) levels (correlation coefficients: normal: r = 0.78; congestive heart failure: r = 0.76; chronic renal failure: r = 0.86; Cushing's syndrome: r = 0.57). High pressure liquid chromatographic analysis of dog plasma showed one major peak of N-terminal immunoreactivity corresponding to ANP (1-98).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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I A Kraft S Alexander D Foster R D Leachman H S Lipscomb 《Science (New York, N.Y.)》1970,169(946):694-696
The electrocardiogram and cardiotachogram of a patient with a human heart transplant has been recorded for 72 hours. Within the donor P-QRS-T complex, one can identify the P waves emanating from residual sinoatrial heart tissue of the recipient. The recipient P waves are independent of the donor complexes. A clear circadian rhythm (23.4 hours) in heart rate is maintained for both donor and recipient tissue, the donor complexes preceding by a phase shift of 135 minutes the complexes of the recipient heart tissue. Both tissues display clear morning and evening minimum and maximum rates paralleling activity and lighting cycles. 相似文献
60.
Upon intravenous transplantation, hematopoietic stem cells (HSCs) can home to specialized niches, yet most HSCs fail to engraft unless recipients are subjected to toxic preconditioning. We provide evidence that, aside from immune barriers, donor HSC engraftment is restricted by occupancy of appropriate niches by host HSCs. Administration of ACK2, an antibody that blocks c-kit function, led to the transient removal of >98% of endogenous HSCs in immunodeficient mice. Subsequent transplantation of these mice with donor HSCs led to chimerism levels of up to 90%. Extrapolation of these methods to humans may enable mild but effective conditioning regimens for transplantation. 相似文献