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排序方式: 共有2408条查询结果,搜索用时 13 毫秒
31.
Krasinskas AM Abraham SC Metz DC Furth EE 《The American journal of surgical pathology》2003,27(2):236-241
Gastric polyps are often present in the setting of atrophic gastritis. Although the majority of these polyps are nonneoplastic, such as hyperplastic polyps, neoplastic polyps may be present. We discuss nine cases that illustrate an additional nonneoplastic cause of polyps in atrophic gastritis. Specifically, preserved islands of relatively normal oxyntic mucosa in a background of gastric atrophy may appear polypoid endoscopically. The patients (seven women, two men, mean age 64 years) presented with nonspecific abdominal or reflux symptoms (n = 8) and diarrhea (n = 1). Five of five patients tested were confirmed to have hypergastrinemia, and three of three patients tested had antiparietal cell antibodies. Biopsies from the gastric body or fundus of our nine patients showed fragments of atrophic mucosa and separate fragments of preserved oxyntic mucosa. Based upon the histologic characteristics of the atrophic fundic and relatively normal antral biopsies, the gastric atrophy appeared to be of autoimmune-type. The relatively preserved oxyntic glands showed parietal cell hypertrophy and focal mild chronic inflammation. The number of polyps observed endoscopically ranged from less than five to multiple/diffuse. Three patients had persistent nodularities in their stomachs for 1, 3, and 7 years of their follow-up. Our study shows that some patients with atrophic gastritis, autoimmune-type, may present with gastric polyps/nodules that represent relatively preserved oxyntic mucosa. This presentation may be more common than is presently recognized because biopsies of the polyps alone will not show histologic features of atrophic gastritis or reveal the etiology of the polyp itself. Although a limited number of previous studies have suggested this type of polypoid presentation may represent "early" atrophic gastritis, its persistence in three of our patients argues against this hypothesis. 相似文献
32.
Peter Scheunemann Nikolas H. Stoecklein Alexander Rehders Minu Bidde Sylvia Metz Matthias Peiper Claus F. Eisenberger Jan Schulte am Esch Wolfram T. Knoefel Stefan B. Hosch 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2008,393(3):359-365
Background and aims Occurrence of tumor relapse is frequent in patients with pancreatic cancer despite the absence of residual tumor detectable
at primary surgery and in histopathological examination. Therefore, it has to be assumed that current tumor staging procedures
fail to identify minimal amounts of disseminated tumor cells, which might be precursors of subsequent metastatic relapse.
The aim of this study was to assess the prognostic impact of minimal tumor cell spread detected in lymph nodes classified
as “tumor-free” in routine histopathologic evaluation.
Materials and methods A total of 154 “tumor-free” lymph nodes from 59 patients with pancreatic cancer who underwent intentionally curative tumor
resection were examined by immunohistochemistry for disseminated tumor cells.
Results Fifty (32.5%) of the “tumor-free” lymph nodes obtained from 36 (61%) patients displayed disseminated tumor cells. Multivariate
survival analysis revealed that the presence of disseminated tumor cells in “tumor-free” lymph nodes is an independent prognostic
factor for both a significantly reduced relapse-free survival (p = 0.03) and overall survival (p = 0.02).
Conclusions The frequent occurrence and prognostic impact of immunohistochemically identifiable disseminated tumor cells in lymph nodes
of patients with operable pancreatic cancer supports the need for a refined staging system of excised lymph nodes, which should
include immunohistochemical examination. 相似文献
33.
Tracy Pitt Stacy Brethauer Vadim Sherman Suthep Udomsawaengsup Matt Metz Silas Chikunguwo Bipan Chand Philip Schauer 《Surgery for obesity and related diseases》2008,4(3):394-8; discussion 398
BACKGROUND: To evaluate, in an observational study, the utility of diagnostic laparoscopy as a tool to evaluate patients with abdominal pain of unknown etiology after gastric bypass surgery. METHODS: A retrospective analysis was performed of data from patients who had undergone laparoscopy for diagnosis or treatment of abdominal pain. This study included 13 patients with negative preoperative radiographic and/or endoscopic findings. RESULTS: A total of 13 patients who had undergone Roux-en-Y gastric bypass underwent diagnostic laparoscopy for abdominal pain. The findings included internal hernia (4), adhesions (3), ventral hernia (2), partial small bowel obstruction (1), and chronic cholecystitis (1). There were 2 negative laparoscopies, while a diagnosis was made in 85%. After an average follow-up of 3.2 months, 7 of 11 patients had unresolved abdominal pain and 4 patients experienced pain resolution (2 patients were lost to follow-up). CONCLUSION: The results from this small retrospective study suggest that significant pathologic findings can be identified in most patients who have negative preoperative evaluation findings; however, the efficacy of diagnostic laparoscopy to eliminate pain in this patient population requires additional study. Despite the potential complications, we believe that diagnostic laparoscopy has a role in the diagnosis and treatment of chronic abdominal pain after gastric bypass. 相似文献
34.
Background: Limited blood supplies necessitate the rational use of blood products. The aim of the present study was to provide a basis for audits of red cell usage in surgery by benchmarking common practice. Application of the data to the construction of a maximum surgical blood order schedule may be relevant for centres that perform a serological crossmatch or who collect autologous units. Methods: Data on surgical procedures identified by Commonwealth Medical Benefits Schedule item numbers, were collected retrospectively from theatre and blood bank records at the Royal Melbourne and Melbourne Private hospitals from May 1997 to April 1998. The percentage of procedures for which red cells were transfused, and the mean, median and range of units transfused for procedures with ≥ 30% transfusion likelihood were identified. Results: Over 12 months, 266 surgical procedure codes were itemized ≥ 10 times each, contributing 12 300 data entries. Only 38 procedures demonstrated an incidence of transfusion of at least 30%. Most frequently transfused procedures included spinal fusion, total hip replacement, mandible/maxilla resection, prostatectomy and bladder excision. Conclusion: The number of common surgical procedures in which there is a 30% or greater likelihood that red cell transfusions will be given is limited. This benchmarking of common red cell usage is a first step in the process of determination of transfusion appropriateness. 相似文献
35.
Alterations in intervertebral disc composition,matrix homeostasis and biomechanical behavior in the UCD‐T2DM rat model of type 2 diabetes 下载免费PDF全文
Aaron J. Fields Britta Berg‐Johansen Lionel N. Metz Stephanie Miller Brandan La Ellen C. Liebenberg Dezba G. Coughlin James L. Graham Kimber L. Stanhope Peter J. Havel Jeffrey C. Lotz 《Journal of orthopaedic research》2015,33(5):738-746
Type 2 diabetes (T2D) adversely affects many tissues, and the greater incidence of discogenic low back pain among diabetic patients suggests that the intervertebral disc is affected too. Using a rat model of polygenic obese T2D, we demonstrate that diabetes compromises several aspects of disc composition, matrix homeostasis, and biomechanical behavior. Coccygeal motion segments were harvested from 6‐month‐old lean Sprague‐Dawley rats, obese Sprague‐Dawley rats, and diabetic obese UCD‐T2DM rats (diabetic for 69 ± 7 days). Findings indicated that diabetes but not obesity reduced disc glycosaminoglycan and water contents, and these degenerative changes correlated with increased vertebral endplate thickness and decreased endplate porosity, and with higher levels of the advanced glycation end‐product (AGE) pentosidine. Consistent with their diminished glycosaminoglycan and water contents and their higher AGE levels, discs from diabetic rats were stiffer and exhibited less creep when compressed. At the matrix level, elevated expression of hypoxia‐inducible genes and catabolic markers in the discs from diabetic rats coincided with increased oxidative stress and greater interactions between AGEs and one of their receptors (RAGE). Taken together, these findings indicate that endplate sclerosis, increased oxidative stress, and AGE/RAGE‐mediated interactions could be important factors for explaining the greater incidence of disc pathology in T2D. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:738–746, 2015. 相似文献
36.
37.
Bastos Gonçalves F Metz R Hendriks JM Rouwet EV Muhs BE Poldermans D Verhagen HJ 《The Journal of cardiovascular surgery》2010,51(5):657-667
Aortic dissection is a devastating cardiovascular condition with an incidence of 3,5:100 000. It is classified according to anatomic extent, mechanism of lesion, duration from index event and course (uncomplicated vs. complicated). Intramural hematoma and penetrating aortic ulcers share many of the features of classic dissections, but tend to occur in older patients with advanced atherosclerosis. In uncomplicated type-B dissection, conservative treatment with tight blood pressure and heart rate control is safe and effective. Early stent-graft implantation may, however, result in more favorable aortic remodeling and reduced late complications. For acute complicated cases intervention is usually required. Stent-graft coverage of the entry tear frequently resolves malperfusion, but the role of the false lumen in organ perfusion must be assessed and endovascular revascularization performed if necessary. In chronic type-B dissections, coverage of the entry tear likely results in continued pressurization of the false lumen due to rigidity of the dissecting membrane and distal fenestrations. Better understanding of the different disease mechanisms involved, imaging advances and introduction of dedicated stent-grafts are expected to further improve patient outcomes in the future. Primary and secondary pharmacological prevention, stricter follow-up protocols and screening of family members may also prove valuable. Better patient selection will allow preventive treatment with low morbidity for those at higher risk of complications. 相似文献
38.
Marcus Maurer Markus Magerl Martin Metz Torsten Zuberbier 《Journal der Deutschen Dermatologischen Gesellschaft》2013,11(10):971-978
At the end of 2012, more than 300 participants discussed and agreed on the update of the international guidelines on urticaria at the 4th International Consensus Meeting (URTICARIA 2012). Currently, the recommendations are in the final process of international coordination. In preparation for the update, questions were prepared by an expert panel; this was followed by a systematic literature search. The questions and the resulting recommendations were discussed by the participants and decided upon in an open vote. Consensus was defined as at least 75% agreement. The updated guidelines will modify and improve the currently available guidelines in various areas, especially in therapy. For the treatment of chronic urticaria, the new algorithm recommends a three‐step process starting with a standard dose of a non‐sedating H1 antihistamine. If there is an insufficient treatment response, the dosage should be increased up to four times. In, therapy refractory patients, omalizumab, cyclosporine A, or montelukast are advised in the third step. Short‐term corticosteroid treatment for a maximum of 10 days may be considered. H2 antihistamines and dapsone, which were included in the previous version of the guidelines, are absent in the updated and revised version because of changes in the evidence level. 相似文献
39.
Renal gluconeogenesis and increased glucose utilization in shock 总被引:1,自引:0,他引:1
40.
The prognostic value of normal exercise myocardial perfusion imaging and exercise echocardiography: a meta-analysis. 总被引:2,自引:0,他引:2
Louise D Metz Mary Beattie Robert Hom Rita F Redberg Deborah Grady Kirsten E Fleischmann 《Journal of the American College of Cardiology》2007,49(2):227-237
OBJECTIVES: The purpose of this work was to determine the prognostic value of normal exercise myocardial perfusion imaging (MPI) tests and exercise echocardiography tests, and to determine the prognostic value of these imaging modalities in women and men. BACKGROUND: Exercise MPI and exercise echocardiography provide prognostic information that is useful in the risk stratification of patients with suspected coronary artery disease (CAD). METHODS: We searched the PubMed, Cochrane, and DARE databases between January 1990 and May 2005, and reviewed bibliographies of articles obtained. We included prospective cohort studies of subjects who underwent exercise MPI or exercise echocardiography for known or suspected CAD, and provided data on primary outcomes of myocardial infarction (MI) and cardiac death with at least 3 months of follow-up. Secondary outcomes (unstable angina, revascularization procedures) were abstracted if provided. Studies performed exclusively in patients with CAD were excluded. RESULTS: The negative predictive value (NPV) for MI and cardiac death was 98.8% (95% confidence interval [CI] 98.5 to 99.0) over 36 months of follow-up for MPI, and 98.4% (95% CI 97.9 to 98.9) over 33 months for echocardiography. The corresponding annualized event rates were 0.45% per year for MPI and 0.54% per year for echocardiography. In subgroup analyses, annualized event rates were <1% for each MPI isotope, and were similar for women and men. For secondary events, MPI and echocardiography had annualized event rates of 1.25% and 0.95%, respectively. CONCLUSIONS: Both exercise MPI and exercise echocardiography have high NPVs for primary and secondary cardiac events. The prognostic utility of both modalities is similar for both men and women. 相似文献