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21.
BackgroundPostoperative hyperamylasemia is a frequent finding after pancreatoduodenectomy, but its incidence and clinical implications have not yet been analyzed systematically. The aim of this review is to reappraise the concept of postoperative hyperamylasemia with postoperative acute pancreatitis, including its definition, interpretation, and correlation.MethodsOnline databases were used to search all available relevant literature published through June 2019. The following search terms were used: “pancreaticoduodenectomy,” “amylase,” and “pancreatitis.” Surgical series reporting data on postoperative hyperamylasemia or postoperative acute pancreatitis were selected and screened.ResultsAmong 379 screened studies, 39 papers were included and comprised data from a total of 9,220 patients. Postoperative hyperamylasemia was rarely defined in most of these series, and serum amylase values were measured at different cutoff levels and reported on different postoperative days. The actual levels of serum amylase activity and the representative cutoff levels required to reach a diagnosis of postoperative acute pancreatitis were markedly greater on the first postoperative days and tended to decrease over time. Most studies analyzing postoperative hyperamylasemia focused on its correlation with postoperative pancreatic fistula and other postoperative morbidities. The incidence of postoperative acute pancreatitis varied markedly between studies, with its definition completely lacking in 40% of the analyzed papers. A soft pancreatic parenchyma, a small pancreatic duct, and pathology differing from cancer or chronic pancreatitis were all predisposing factors to the development of postoperative hyperamylasemia.ConclusionPostoperative hyperamylasemia has been proposed as the biochemical expression of pancreatic parenchymal injury related to localized ischemia and inflammation of the pancreatic stump. Such phenomena, analogous to those associated with acute pancreatitis, could perhaps be renamed as postoperative acute pancreatitis from a clinical standpoint. Patients with postoperative acute pancreatitis experienced an increased rate of all postoperative complications, particularly postoperative pancreatic fistula. Taken together, the discrepancies among previous studies of postoperative hyperamylasemia and postoperative acute pancreatitis outlined in the present review may provide a basis for stronger evidence necessary for the development of universally accepted definitions for postoperative hyperamylasemia and postoperative acute pancreatitis.  相似文献   
22.
ObjectiveTo identify in which cases after cytological diagnosis, the Bladder EpiCheck test could represent an effective tool in non-muscle invasive bladder carcinoma or an useless expence.Materials and methods375 patients diagnosed with non-muscle invasive bladder cancer, 269 with high grade urothelial carcinoma and 106 with carcinoma in situ, were treated and followed for 1 year. The treatment was an intravesical instillation of Bacillus Calmette-Guerin in 305 patients and Mitomycin-C in 70 patients.During the follow-up patients were evaluated by voided urine cytology and white-light cystoscopy, according to the European Association of Urology Guidelines. Bladder EpiCheck test was performed together with cytology in all cases.ResultsAnalyzing Bladder Epicheck results for each category defined by the Paris System for Reporting Urinary Cytology, we found that the Episcore >60 correlates with histological diagnosis of high grade urothelial carcinoma (HGUC) in atypical urothelial cells and Suspicious for High Grade Urothelial Carcinoma (P = 0.0002 Odds Ratio 0.05926 95% Confidence Interval from 0.01127 to 0.3116 and P = 0.0009 Odds Ratio 0.0315595% Confidence Interval from 0.001683 to 0.5914, Fisher's exact test, respectively), while in Negative for high grade urothelial carcinoma and HGUC patients Episcore is not helpful to identify cases with histological diagnosis of HGUC (P = 0.101 and P = 0.58 Fisher's exact test, respectively). Considering an Episcore ≥ 90 in the HGUC cytological group, this seems not to be correlated with a histological diagnosis of HGUC (P = 0.090 Fisher's exact test).ConclusionsCytology and Bladder EpiCheck test in combination may have the potential to reduce cystoscopies in the follow-up of non-muscle invasive bladder cancer only for cytological diagnoses of atypical urothelial cells and Suspicious for High Grade Urothelial Carcinoma . Moreover, in patients with a cytological diagnosis of Negative for high grade urothelial carcinoma or HGUC, cytology alone seems to be safe and cost-effective.  相似文献   
23.
PURPOSE: Missing cervical spine fractures during the initial plain film study may lead to severe neurological complications for patients and to medicolegal responsibilities for the physician. The upper cervical spine tract (C1-C2) is considered to be at high risk for misdiagnoses. We decided to investigate the possible causes of mistake in the cases of missed fractures on the initial plain film, performed in the emergency room. MATERIAL AND METHODS: We retrospectively reviewed the radiological reports, the original plain films and the CT findings, of 32 patients with upper cervical (C1-C2) fractures, admitted January 1994 to December 1998. Twenty-eight of these patients (87.5%) had multisystem trauma, 4 (12.5%) had minor craniocervical trauma. None of these patients had neurological signs correlated to the cervical injuries, 30 of them had normal consciousness and reported only neck pain, 2 of them were unconscious for the associated head trauma and were hospitalized in the intensive care unit. All the patients with normal consciousness underwent conventional three-view cervical spine radiography; the two unconscious patients in the intensive care unit were submitted to bedside examination with an anteroposterior and a lateral views of the cervical spine. All patients underwent spiral CT of the upper cervical tract. RESULTS: In 9 of 32 patients (28%) a cervical fracture was missed on the plain film and CT was performed only because of persistent neck pain. We found 2 Jefferson's fractures, 2 type II dens fractures, one type I dens fracture and 4 hangman's fractures. In 8 of the 9 patients (89%) the fracture was potentially unstable. Misdiagnoses resulted from overlapping bone structures (3%), suboptimal film quality (3%), satisfaction of search phenomenon (3%), missed mild tilting of the dens (6%), missed double cortex sign (16%), missed C1-C2 lateral subluxation (6%) and marked osteoporosis (3%). Prevertebral soft tissue swelling was not seen in any of the 9 cases of missed fractures. Considering the group of patients with C1-C2 fractures separately, the false negative rate is 28%, which corresponds to 10.7% of the total number of patients with cervical fractures and dislocations examined during the same period. CONCLUSIONS: Among the causes of false-negative interpretation, osteoporosis, suboptimal film quality due to associated fractures and overlapping bone structures must be considered unavoidable. On the other hand these possibilities should be indicated on the X-ray report because, if painful symptoms persist, a CT exam is strongly advised. Subtle alterations like dens tilting, double cortex sign, lateral subluxation of C1 and prevertebral soft tissue swelling should be regarded as highly suspicious for fracture. Missing these lesions might be considered a true diagnostic mistake with possible legal consequences, which may also expose the patient to the risk of neurological complications. The satisfaction of search phenomenon can be avoided only by trying to use a search pattern for every film, which includes checking all the visible anatomical structures even in the presence of a particularly evident lesion. In all questionable cases or high-risk fracture patients, even with an apparently negative plain film, it is advisable to perform CT instead of additional plain films. Finally, in all the patients treated in the intensive care unit for head trauma, an upper cervical CT scan should be routinely carried out at the same time as the brain scan.  相似文献   
24.
We recently identified the direct product of dopamine (DA) by monoamine-oxidase (MAO) activity, dihydroxyphenylacetaldehyde (DOPALD) in the trans-striatal dialysate. Based on these findings, in this work, we directly measured the variations in DOPALD levels after various kinds of pharmacological treatment in rat striatal extracellular fluid. Using both reversible and irreversible MAO inhibitors, we found that MAO-A inhibition suppressed, whereas MAO-B inhibition did not modify DOPALD levels in the dialysate. The vesicular DA uptake blocker Ro 4-1284 led to an increase in extracellular DA and DOPALD, whereas the increase in extracellular DA obtained after administration of the plasma membrane DA uptake blocker GBR-12909 occurred without concomitant changes in DOPALD extracellular levels. Microinfusions of DA through the dialysis probe or systemic administration of L-DOPA increased striatal DOPALD to a greater extent compared with other DA metabolites, both in intact and in 6-hydroxydopamine (6-OHDA)-lesioned striatum. This study indicates that the direct product of MAO activity within the rat striatum derives from the activity of the isoenzyme MAO-A. The assay of DOPALD, together with DOPAC, represents a reliable tool to measure directly, in freely moving animals, DA oxidative metabolism. As recent studies have shown that microinfusions of exogenous DOPALD might induce cell death, pharmacological modulation of DOPALD levels might also be relevant for an understanding of the mechanisms involved in DA neurotoxicity.  相似文献   
25.
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
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Psychosocial factors such as social support and depression have long been associated with health outcomes. Elevated depressive symptoms are usually associated with worse health outcomes, whereas social support has been related to improvements in health. Nitric oxide levels are an important marker of both cardiovascular health and immune function. Research suggests that exhaled nitric oxide is affected by stress, negative affect, and depression; however, the effect of social support has not been previously explored. Thus, we sought to examine the association of social support, negative affect, and depression with exhaled nitric oxide in a group of 35 healthy individuals (10 males and 25 females) with a mean age of 20.5 years across five weekly assessments. Results showed that changes in social support within individuals were positively associated with levels of exhaled nitric oxide independent of other psychosocial factors. Further exploration of the health implications of this positive relationship between airway nitric oxide and social support is necessary.  相似文献   
30.
Lung ultrasound (LU) has rapidly become a tool for assessment of patients stricken by the novel coronavirus 2019 (COVID-19). Over the past two and a half months (January, February, and first half of March 2020) we have used this modality for identification of lung involvement along with pulmonary severity in patients with suspected or documented COVID-19 infection. Use of LU has helped us in clinical decision making and reduced the use of both chest x-rays and computed tomography (CT).  相似文献   
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