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51.
DV Beard PL Molina KE Muller KM Denelsbeck BM Hemminger JR Perry MP Braeuning DH Glueck WD Bidgood M Mauro 《Canadian Metallurgical Quarterly》1995,197(3):753-758
PURPOSE: Interpretation time of serial staging chest CT cases, which each contained current and previous examinations, with a simple prototype workstation called filmstack was experimentally compared with interpretation time with a film alternator. MATERIALS AND METHODS: The filmstack displayed a "stack" of sections for each examination; user controls allowed rapid selection of preset attenuation windows and both synchronized and unsynchronized scrolling. Eight radiologists were timed as they used the filmstack and the film alternator to interpret four ergonomically complex serial CT cases. RESULTS: All reports dictated on the basis of findings with filmstack and film were of acceptable clinical accuracy. The time to examine a case with filmstack was significantly faster than the time with film, including the time to load and unload the alternator (99% confidence [P = .01]). There was no statistically significant difference in interpretation time between filmstack and prehung film. CONCLUSION: Use of a low-cost stacked CT workstation with a single 1,024 x 1,024 monitor is an effective means of interpreting cases that require comparison of multiple CT examinations. 相似文献
52.
GM Weinstock JM Hardham MP McLeod EJ Sodergren SJ Norris 《Canadian Metallurgical Quarterly》1998,22(4):323-332
Covert brain activity related to task-free, spontaneous (i.e. unrequested), emotional evaluation of human face images was analysed in 27-channel averaged event-related potential (ERP) map series recorded from 18 healthy subjects while observing random sequences of face images without further instructions. After recording, subjects self-rated each face image on a scale from "liked" to "disliked". These ratings were used to dichotomize the face images into the affective evaluation categories of "liked" and "disliked" for each subject and the subjects into the affective attitudes of "philanthropists" and "misanthropists" (depending on their mean rating across images). Event-related map series were averaged for "liked" and "disliked" face images and for "philanthropists" and "misanthropists". The spatial configuration (landscape) of the electric field maps was assessed numerically by the electric gravity center, a conservative estimate of the mean location of all intracerebral, active, electric sources. Differences in electric gravity center location indicate activity of different neuronal populations. The electric gravity center locations of all event-related maps were averaged over the entire stimulus-on time (450 ms). The mean electric gravity center for disliked faces was located (significant across subjects) more to the right and somewhat more posterior than for liked faces. Similar differences were found between the mean electric gravity centers of misanthropists (more right and posterior) and philanthropists. Our neurophysiological findings are in line with neuropsychological findings, revealing visual emotional processing to depend on affective evaluation category and affective attitude, and extending the conclusions to a paradigm without directed task. 相似文献
53.
The dimer of bovine pancreatic ribonuclease A (RNase A) discovered by Crestfield, Stein, and Moore in 1962 has been crystallized and its structure determined and refined to a 2.1-A resolution. The dimer is 3D domain-swapped. The N-terminal helix (residues 1-15) of each subunit is swapped into the major domain (residues 23-124) of the other subunit. The dimer of bull seminal ribonuclease (BS-RNase) is also known to be domain-swapped, but the relationship of the subunits within the two dimers is strikingly different. In the RNase A dimer, the 3-stranded beta sheets of the two subunits are hydrogen-bonded at their edges to form a continuous 6-stranded sheet across the dimer interface; in the BS-RNase dimer, it is instead the two helices that abut. Whereas the BS-RNase dimer has 2-fold molecular symmetry, the two subunits of the RNase A dimer are related by a rotation of approximately 160 degrees. Taken together, these structures show that intersubunit adhesion comes mainly from the swapped helical domain binding to the other subunit in the "closed interface" but that the overall architecture of the domain-swapped oligomer depends on the interactions in the second type of interface, the "open interface." The RNase A dimer crystals take up the dye Congo Red, but the structure of a Congo Red-stained crystal reveals no bound dye molecule. Dimer formation is inhibited by excess amounts of the swapped helical domain. The possible implications for amyloid formation are discussed. 相似文献
54.
P Franco O Massa M Garcia-Rocha F Chiaradonna C Iaccarino I Correas E Mendez J Avila F Blasi MP Stoppelli 《Canadian Metallurgical Quarterly》1998,273(42):27734-27740
We recently reported that in vivo phosphorylation of urokinase-type plasminogen activator on Ser138/303 prevents its catalytic-independent ability to promote myelomonocytic cell adherence and motility. We now show that Ca2+ activated, phospholipid-dependent protein kinase C from rat brain phosphorylates in vitro a peptide corresponding to prourokinase residues 133-143 (DGKKPSSPPEE) and the full-length molecule on Ser138/139. The in vivo involvement of the protein kinase C isoenzyme family is supported by the finding that inhibition of kinase C activity prevents prourokinase phosphorylation on Ser138/303 in A431 human carcinoma cells. Conversely, a short treatment of A431 cells with phorbol myristate acetate increases the extent of phosphorylated prourokinase and, concomitantly, affects its function; under these conditions, the capability of prourokinase to up-regulate U937 monocyte-like cell adherence is severely impaired, although receptor binding is unaltered. By the aid of a "phosphorylation-like" variant (Ser138 to Glu) we show that modification of Ser138 is sufficient to confer to prourokinase the antagonistic properties observed following in vivo stimulation of protein kinase C activity. These observations provide the first evidence that protein kinase C directs the formation of a receptor competitive antagonist by regulating the in vivo phosphorylation state of prourokinase. 相似文献
55.
A new image analysis-based technique was used to quantitatively examine the effects of the "Ca2+-jump" activation protocol on the maintenance of fiber quality in skinned rabbit psoas muscle fiber segments. Specifically, contractions in pCa 4.6 were preceded by short-duration "preactivation" soaks in a solution in which EGTA was replaced with the low-Ca2+ buffering capacity analog hexamethylenediamine-N, N, N', N'-tetraacetate, which facilitated rapid Ca2+ equilibration within the fiber segments. Fiber quality was assessed by examining the Fourier spectra of the muscle fiber images before, during, and after activation. Segment lengths were typically below 500 micrometer, thus allowing the majority of the sarcomeres to be visualized in the field of view (x200 and x400 magnification). The preactivation protocol resulted in less deterioration of fiber quality with repetitive activation. In addition, there was also a significant reduction in the time required to reach the 50% level of maximum tension, with no significant change in the maximum tension level. 相似文献
56.
We sought to compare self-assessment of preoperative anxiety levels and selection of worst fears by surgical patients with the assessments made by the anesthesia and surgery residents providing intraoperative care for those patients. One hundred inpatients at a Veterans Affairs hospital (Group 1) and 45 patients at a University hospital (Group 2) were asked to complete a brief questionnaire; the residents were asked to complete the same questionnaire. Group 1 results showed that median patient visual analog scale (VAS) scores were lower for anxiety about anesthesia compared to surgery (16 vs 22, P < or = 0.05). Anesthesia resident VAS scores were higher than patient or surgery resident scores. Neither type of resident was able to predict their individual patient's VAS score (Kendall's tau). The fear chosen with the greatest incidence by Group 1 patients and residents was "whether surgery would work". A significant number of residents (34%, anesthesia or surgery, P < or = 0.05) matched their patient's fear choice. Residents commonly chose fears related to their specialty (e.g., anesthesia residents chose anesthesia-related fears more often than surgery residents, 50% vs 28%, P < or = 0.001). In Group 2, residents demonstrated an improved ability to predict patient scores. For instance, both surgery and anesthesia residents were able to predict individual University patient VAS scores (P < or = 0.01). The fear chosen with the greatest frequency by Group 2 patients was "pain after the operation". Sixty percent of anesthesia residents matched their patients' fear choice (P < or = 0.001). This study indicates a variable ability of anesthesia and surgery residents to predict patient anxiety and fear which may be due, in part, to difficulty in understanding a Veterans Affairs hospital patient population. 相似文献
57.
C Mabit P Salanne MP Boncoeur-Martel F Fiorenza D Valleix B Descottes M Caix 《Canadian Metallurgical Quarterly》1996,80(249):17-21
The anatomy of the malleolar peroneal groove is presented. The results are based on a coupled osteological and CTscan study of 20 samples of fibulae. The average distal fibular torsion was 64 degrees. The peroneal groove was oriented posteriorly (mean value: 78 degrees). Three types of morphological variations were found: concave, flat, convex (the convex shaped groove was the most frequent one: 70%). The average width of the groove was 9 mm. These morphometric results were compared to "clinical" ones performed on patients with a peroneal tendons dislocation syndrome: CTscan study showed an osseous dysplasia concerning the groove depth (flat or convex) and/or a torsional insufficiency. Hypothesis of a bone dysplasia in peroneal dislocation syndrome is discussed. 相似文献
58.
Olle EW Deogracias MP Messamore JE McClintock SD Barron AG Anderson TD Johnson KJ 《Proteomics. Clinical applications》2007,1(10):1212-1220
Wegener's Granulomatosis (WG) is an idiopathic granulomatosis autoimmune vasculitis that primarily affects small vessels and is associated with glomerulonephritis and pulmonary granulomatous vasculitis. Anti‐neutrophil cytoplasmic auto‐antibodies (cANCA) against proteinase‐3 are used to identify WG, but ANCA titers are not present in some patients with the localized disease. The objective of this study was to develop an antibody array to help identify protein expression patterns in serum from patients with WG as compared to normals. The arrays were tested for limits of detection, background, and cross reactivity using standard proteins. The arrays were hybridized with either normal patient serum (n = 30) or with serum samples from a population of WG patients (n = 26) that were age and sex matched. Data analysis and curve fitting of the standard dilution series calculated r2 values and determined a sensitivity of <50 pg/mL for the majority of proteins. A total of 24 proteins were assessed. Several statistically significant increases (p<0.05) were seen in the expression of: angiotensin converting enzyme‐I, IFN‐γ, IL‐8, s‐ICAM‐1 and s‐VCAM in WG patients as compared to controls. Utilizing the antibody microarray technology has led to the identification of potential biomarkers of vascular injury in the serum of WG patients. 相似文献
59.
Using selected incubation conditions we have identified intermediate steps, between the first glucose transferred to protein and the appropriate substrate for glycogen synthase. Mn2+ stimulates the addition of the first, and probably, the second glucose molecule to the acceptor protein but inhibits further elongation. In the presence of Mn2+ only one radioglucosylated protein band of M(r) 42 kDa was evident. In the absence of Mn2+, two bands of 60.7 and 64.6 kDa were obtained indicating elongation of the glucan chains. After Glc6P addition a family of glucosylated proteins with higher M(r) was obtained, as reported previously. Mn2+ inhibition of the second step, is reversed by PMSF+Glc6P addition. Under these conditions a family of radioglucosylated protein bands with M(r) far in excess of 42 kDa, similar to that obtained without Mn2+, was obtained. Therefore, two different transglucosylating activities were necessary, at least, to prepare the appropriate substrate for glycogen synthase. Based on these observations the model we proposed earlier for glycogen biogenesis is modified. The original "Glycogen Initiator" implies at present two enzymatic activities, Glycogen Initiator 1 (activated by Mn2+) and Glycogen Initiator 2 (inhibited by Mn2+). 相似文献
60.
We recorded clinical information over a 12-month period on consecutive consultations to the gastroenterology service of the Durham VA Medical Center. Of 902 consultations, 789 were prospectively collected. Eighty-five percent of the patients were between 40 and 70 years old. Seventy-five percent of the referrals were from the internal medicine service. The most frequent reasons for consultation were abdominal pain (19%), GI bleeding (active, 16%; occult, 9%), abnormal results of liver tests (18%), and request for a procedure (11%). Diseases of the liver (32%) and "peptic diseases" (30%) were the most common diagnoses. One or more procedures were done in 71% of consultations. When these data are compared with those of a practicing gastroenterologist, using an identical instrument, it is apparent that trainees' experience with structurally identifiable gastroenterologic disease and with a variety of procedures was similar in scope. There were, however, differences in that the physicians at the VA saw substantially fewer patients with so-called "functional" illness. If these data are applicable to other VA Medical Centers, then the training of physicians in gastroenterology at a VA Medical Center should probably be broadened. 相似文献