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排序方式: 共有660条查询结果,搜索用时 31 毫秒
21.
Lorenzo Fuccio Douglas Rex Thierry Ponchon Leonardo Frazzoni Mário Dinis-Ribeiro Pradeep Bhandari Evelien Dekker Maria Pellisè Loredana Correale Jeanin van Hooft Rodrigo Jover Diogo Libanio Franco Radaelli Sergio Alfieri Franco Bazzoli Carlo Senore Jaroslaw Regula Thomas Seufferlein Cesare Hassan 《Gastroenterology》2019,156(5):1309-1323.e3
22.
Fritsch G; Buchinger P; Printz D; Fink FM; Mann G; Peters C; Wagner T; Adler A; Gadner H 《Blood》1993,81(9):2301-2309
Mononuclear cells (MNC) isolated by density centrifugation of cord blood and healthy bone marrow, and of peripheral blood (PB) from patients treated with granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF after chemotherapy, were double-stained with anti CD34 monoclonal antibody (MoAb) (8G12) versus anti CD45, CD45-RB, CD45- RO, and CD45-RA, respectively, and analyzed by flow cytometry. In all specimens, CD34+ MNC co-expressed CD45 at a low level and the expression of CD45-RB was similar or slightly higher. Most CD34+ MNC were negative for CD45-RO, a weak coexpression was only seen in some bone marrow (BM) and blood samples. In contrast, CD45-RA could subdivide the CD34+ population into fractions negative, dim (+), and normal positive (++) for these subgroups, and typical staining patterns were observed for the different sources of hematopoietic cells: in BM, most CD34+ MNC were RA++. In PB, their majority was RA++ after G-CSF but RA+ or RA- after GM-CSF. In cord blood, the hematopoietic progenitors were mainly RA-/RO-. Semisolid culture of sorted CD34+ MNC showed that clusters and dispersed (late) colony-forming unit-GM (CFU- GM) originated from 34+/RA++ cells, while the 34+/RA- MNC formed compact and multicentric, both white and red colonies derived from early progenitors. Addition of 20 ng stem cell factor per milliliter of medium containing 34+/RA- cord blood MNC led to a change of many burst- forming unit-erythrocyte (BFU-E) to CFU-mix which was not, at least to this extent, seen in blood and BM. We conclude that early myeloid CD34+ cells are 45+/RA-. Because this population excludes 34+/19+ B cells and 33+ myeloid cells, both of which are RA++, two-color flow cytometric analysis using CD34 and CD45-RA facilitates the characterization and quantification of early myeloid progenitor cells. 相似文献
23.
Paul T Kr ner Megan ML Engels Benjamin S Glicksberg Kipp W Johnson Obaie Mzaik Jeanin E van Hooft Michael B Wallace Hashem B El-Serag Chayakrit Krittanawong 《World journal of gastroenterology : WJG》2021,27(40):6794-6824
The development of artificial intelligence (AI) has increased dramatically in the last 20 years, with clinical applications progressively being explored for most of the medical specialties. The field of gastroenterology and hepatology, substantially reliant on vast amounts of imaging studies, is not an exception. The clinical applications of AI systems in this field include the identification of premalignant or malignant lesions (e.g., identification of dysplasia or esophageal adenocarcinoma in Barrett’s esophagus, pancreatic malignancies), detection of lesions (e.g., polyp identification and classification, small-bowel bleeding lesion on capsule endoscopy, pancreatic cystic lesions), development of objective scoring systems for risk stratification, predicting disease prognosis or treatment response [e.g., determining survival in patients post-resection of hepatocellular carcinoma), determining which patients with inflammatory bowel disease (IBD) will benefit from biologic therapy], or evaluation of metrics such as bowel preparation score or quality of endoscopic examination. The objective of this comprehensive review is to analyze the available AI-related studies pertaining to the entirety of the gastrointestinal tract, including the upper, middle and lower tracts; IBD; the hepatobiliary system; and the pancreas, discussing the findings and clinical applications, as well as outlining the current limitations and future directions in this field. 相似文献
24.
Practice, efficacy, and costs of thyroid nodule evaluation: a retrospective study in a Dutch university hospital. 总被引:2,自引:0,他引:2
Lotty Hooft Otto S Hoekstra Maarten Boers Maurits W Van Tulder Paul Van Diest Paul Lips 《Thyroid》2004,14(4):287-293
Fine-needle aspiration (FNA) of thyroid nodules has markedly reduced the role of thyroid scintigraphy. This is often limited to nondiagnostic or follicular (tumor) FNA classifications. In this study, we evaluated the efficacy and cost of such a strategy in a university center. From 1992-1998, 995 aspirations were done in 667 patients with palpable nodules. FNA was classified as malignant, suspicious, follicular, benign or inadequate. The Gold standard was surgery or extended follow-up, including physical examination, FNA, and/or ultrasound (US) with a time interval of half a year. Cost analysis was limited to operated patients. The first FNA yielded inadequate results in 28%, decreasing to 6% after 4 aspirations (n = 42). The other final classifications were: 76%, benign; 14%, follicular; 2%, suspicious; 1%, malignant (n = 7). Scintigraphy ((99m)Tc) suggested a hyperfunctioning autonomous nodule (adenoma) in 12% and 3% of the inadequate and follicular subset, respectively. Surgery for diagnostic reasons (n = 105) yielded 24 malignancies (23%): in 47% of suspicious, 12% of the follicular, and in all with malignant FNA. Postoperative morbidity occurred in 14 (5 laryngeal nerve paralyses) with benign histology. Major cost drivers were surgery and hospitalization: mean costs per patient amounting to Euro 3.311 in case of benign histology. We conclude that current work-up is still unable to prevent unnecessary surgery for benign thyroid nodules. Thyroid scintigraphy proved most productive in the inadequate FNA category. Improvement of the diagnostic process using immunohistochemistry and/or imaging is needed from the patient's and society's perspective. 相似文献
25.
Hooft L van der Veldt AA Hoekstra OS Boers M Molthoff CF van Diest PJ 《Clinical endocrinology》2008,68(2):252-257
Background Distinguishing malignant thyroid nodules in patients with follicular cytology by fine‐needle aspiration (FNA) remains problematic. The large majority of thyroid nodules (> 85%) are overtreated. Therefore, a clear need exists to develop more accurate initial diagnostic tests for follicular thyroid nodules. Galectin‐3 is the most recent promising marker to aid discrimination between benign and malignant thyroid lesions; however, this biomarker can be absent in follicular malignancies. Aims This study was undertaken to determine whether additional biomarkers can help to discriminate between benign and malignant thyroid nodules. Methods Surgical specimens of 36 patients with benign (n = 12) and malignant (n = 24) thyroid nodules showing follicular cytology were assessed by immunohistochemistry for the expression of galectin‐3 and novel biomarkers. Results Expression of hexokinase III (HK III) (P = 0·000) cyclin A (P = 0·002) and galectin‐3 (P = 0·003) differed significantly between benign and malignant thyroid nodules. HK III had a sensitivity of 79% [95% confidence interval (CI) 60–91] and a specificity of 100% (95% CI 76–100) in predicting malignancy. Galectin‐3 had a sensitivity of 79% (95% CI 56–91) and a specificity of 75% (95% CI 47–91) in predicting malignancy. Combining HK III, cyclin A and galectin‐3 in a parallel test increased the sensitivity to 96% (95% CI 80–99) while the specificity remained at a high level of 75% (95% CI 47–91). Leave‐one‐out cross‐validation demonstrated a stable predictive validity of a model based on HK III, cyclin A and galectin‐3. Conclusions In this study, we have demonstrated that in addition to galectin‐3, HK III and cyclin A profiles could be important biomarkers in predicting malignancy in follicular thyroid nodules. The use of these biomarkers may allow an accurate preoperative diagnosis of thyroid cancer, which can be cost saving and may avoid serious morbidity such as vocal cord paralysis. The value of the suggested biomarkers warrants further evaluation in a large prospective study on cytological samples of follicular thyroid nodules. 相似文献
26.
Nynke D Scherpbier-de Haan Gerald MM Vervoort Chris van Weel Jozé CC Braspenning Jan Mulder Jack FM Wetzels Wim JC de Grauw 《The British journal of general practice》2013,63(617):e798-e806
Background
Chronic kidney disease (CKD) is highly prevalent in patients with diabetes or hypertension in primary care. A shared care model could improve quality of care in these patientsAim
To assess the effect of a shared care model in managing patients with CKD who also have diabetes or hypertension.Design and setting
A cluster randomised controlled trial in nine general practices in The Netherlands.Method
Five practices were allocated to the shared care model and four practices to usual care for 1 year. Primary outcome was the achievement of blood pressure targets (130/80 mmHg) and lowering of blood pressure in patients with diabetes mellitus or hypertension and an estimated glomerular filtration rate (eGFR)<60ml/min/1.73m2.Results
Data of 90 intervention and 74 control patients could be analysed. Blood pressure in the intervention group decreased with 8.1 (95% CI = 4.8 to 11.3)/1.1 (95% CI = −1.0 to 3.2) compared to −0.2 (95% CI = −3.8 to 3.3)/−0.5 (95% CI = −2.9 to 1.8) in the control group. Use of lipid-lowering drugs, angiotensin-system inhibitors and vitamin D was higher in the intervention group than in the control group (73% versus 51%, 81% versus 64%, and 15% versus 1%, respectively, [P = 0.004, P = 0.01, and P = 0.002]).Conclusion
A shared care model between GP, nurse practitioner and nephrologist is beneficial in reducing systolic blood pressure in patients with CKD in primary care. 相似文献27.
28.
de Jong K van Hooft JE Nio CY Gouma DJ Dijkgraaf MG Bruno MJ Fockens P 《Scandinavian journal of gastroenterology》2012,(47):1056-1063
Abstract Background. Magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) are considered useful techniques in the evaluation of pancreatic cysts. Aim of this study was to prospectively compare the diagnostic value of these techniques. Methods. This study included consecutive patients who underwent MRI, EUS, and EUS-FNA for a pancreatic cyst that was eventually resected surgically. Observers scored for cyst characteristics, a distinction between mucinous and non-mucinous cysts and a suspicion of malignancy. The interobserver agreement between MRI and EUS was calculated. Results. A total of 32 patients were included. Sensitivity for diagnosing a mucinous cyst was 78% for EUS versus 91% for MRI. Sensitivity for detecting malignancy was 25% (1/4) and 50% (2/4) for EUS and MRI respectively. Sensitivity of EUS-FNA for diagnosing a mucinous cyst (positive cytology and/or CEA >192 ng/ml) was 61%. Sensitivity for detecting malignancy (positive cytology) was 1/4 (25%). Interobserver agreement between MRI and EUS for the features was poor to fair. Conclusion. MRI and EUS are comparable techniques for the morphological characterization of pancreatic cysts. Combined sensitivity of EUS and MRI was higher than the sensitivity of one of the techniques alone. For diagnosing a mucinous cyst, FNA findings showed a low sensitivity, but a high specificity. 相似文献
29.
Background
Critically-ill trauma patients have a high mortality.Objective
To study the factors affecting the mortality of ICU trauma patients treated at Al-Ain Hospital, United Arab Emirates (UAE).Methods
All trauma patients who were admitted to the ICU were prospectively collected over three years (2003–2006). Univariate and multivariate analysis were used to compare patients who died and who did not. Gender, age, nationality, mechanism of injury, systolic blood pressure and GCS on arrival, the need for ventilation, presence of head or chest injuries, AIS for the chest and head injuries and the ISS were studied.Results
There were 202 patients (181 males). The most common mechanism of injury was road traffic collisions (72.3 %). The overall mortality was 13.9%. A direct logistic regression model has shown that factors that affected mortality were decreased GCS (p < 0.0001), mechanism of injury (p = 0.004) with burns having the highest mortality, increased age (p = 0.004), and increased ISS (p = 0.02). The best GCS that predicted mortality was 5.5 while the best ISS that predicted mortality was 13.5.Conclusion
Road traffic collision is the most common cause of serious trauma in UAE followed by falls. Decreased GCS was the most significant factor that predicted mortality in the ICU trauma patients. 相似文献30.