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1.
2.
N-3 fatty acids only delay early relapse of ulcerative colitis in remission   总被引:4,自引:0,他引:4  
Relapse prevention by dietary n-3 fatty acids (5.1 g/day) was studied in a double-blind, placebo-controlled trial of 64 patients with ulcerative colitis in remission and off steroids. 5-ASA compounds were stopped three months after randomization and clinical disease activity monitored for two years. Macroscopic and histologic activity and extension was assessed by colonoscopy at entry and at exit. Both treatment groups were well matched at start. Nine patients on placebo and eight on n-3 fatty acids stopped taking their medication prematurely. Actuarial relapse-free survival was improved by n-3 fatty acids only during months 2 and 3 (2P<0.05–0.01), but cumulative relapse rate at two years was similar for those taking placebo (18/33=55%) and n-3 fatty acids (18/31=58%). There was also no consistent difference in clinical, macroscopic, and histologic disease activity between treatment groups. The n-3 fatty acids temporarily retard, but do not prevent, relapse of ulcerative colitis.  相似文献   
3.
Marked neovascularization is a hallmark of many neoplasms in the nervous system. Recent reports indicate that the endothelial mitogen vascular endothelial growth factor (VEGF) may play a critical role in the regulation of vascular endothelial proliferation in malignant gliomas. Using novel monoclonal antibodies to the VEGF polypeptide we have determined the expression and cellular distribution of VEGF protein in a representative series of 171 human central nervous system (CNS) tumors by immunohistochemistry and immunoblotting. In agreement with previous in situ hybridization data, 19 out of 20 glioblastomas (95%) showed immunoreactivity for VEGF, whereas both the percentage of immunoreactive tumors and the extent of immunoreactivity for VEGF were significantly lower in astrocytomas. Of the pilocytic astrocytomas (WHO grade I) 44% were immunoreactive for VEGF, but we observed several cases with pronounced vascular proliferates in the absence of VEGF. In ependymomas, meningiomas, hemangioblastomas, and primitive neuroectodermal tumors, there was no correlation between VEGF expression, vascular endothelial proliferation and the grade of malignancy. Oligodendrogliomas and the oligodendroglial component of mixed gliomas lacked immunoreactive VEGF, indicating that endothelial growth factors other than VEGF may regulate tumor angiogenesis in these neoplasms. Western blot analysis showed a predominant VEGF protein species of 23 kDa and confirmed the immunohistochemical data in all cases. Our findings demonstrate that VEGF is expressed in a wide spectrum of brain tumors in which it may induce neovascularization. However, other angiogenic factors also appear to contribute to the vascularization of CNS neoplasms. Received: 18 April 1996 / Revised, accepted: 20 August 1996  相似文献   
4.
Sperm quality in Hodgkin's disease versus non-Hodgkin's lymphoma   总被引:3,自引:4,他引:3  
The study was conducted to determine the deleterious effect of lymphoma disease on spermatogenesis and to evaluate the possibility that the disease is mediated primarily by inherent mechanisms in Hodgkin's disease and non-Hodgkin's lymphoma patients. A total of 89 patients with lymphoma disease (Hodgkin's and non-Hodgkin's) were referred for sperm preservation prior to adjuvant treatments. A comparison was made of pre- and post-thaw sperm quality between lymphoma patients and healthy volunteers who applied for sperm donation. This was followed by further assessment of the differences between patients with Hodgkin's disease and non-Hodgkin's lymphoma in terms of sperm variables, clinical parameters and blood hormone concentrations. It was found that patients with lymphoma disease had significantly impaired pre-freeze and post-thaw sperm quality compared with that of healthy volunteers. Patients with non-Hodgkin's lymphoma had spermatozoa of higher quality than patients with Hodgkin's disease. No differences were found in the clinical or hormonal parameters between these two groups. As expected, reduced testicular size and abnormal testicular consistency were correlated with decreased sperm quality. The mere presence of cancer disease has a direct negative effect on spermatogenesis, which is probably not related to incidental side-effects. A variable degree of impairment should be expected with different categories of cancer.   相似文献   
5.
About 380 children younger than 16 years of age are diagnosed with a brain tumor in Germany every year. Compared to adults, different types of brain tumors are found in children. The diagnosis is often delayed in spite of presentation with characteristic symptoms. Unspecific persistent symptoms must be followed by further diagnostics. Since the 1980s, multimodal therapeutic regimens have been developed systematically by the Society for Pediatric Oncology and Hematology (GPOH) in the context of treatment optimalization trials. Neurosurgery, chemotherapy and irradiation are applied according to histology, stage of metastasis, and the age of the children. Currently, 80–90% of children diagnosed with a brain tumor in Germany are treated according to the respective trial in the context of the ‘treatment network HIT’. The principle aims are improved survival and quality of life, and the reduction of therapy-associated toxicity and late-effects. In this article, typical clinical symptoms, diagnostic recommendations and current treatment strategies are described.  相似文献   
6.
Monitoring the occurrence of adverse events in the scientific literature is a mandatory process in drug marketing surveillance. This is a very time‐consuming and complex task to fulfill the compliance and, most importantly, to ensure patient safety. Therefore, a machine learning (ML) algorithm has been trained to support this manual intellectual review process, by automatically providing a classification of the literature articles into two types. An algorithm has been designed to automatically classify “relevant articles” which are reporting any kind of drug safety relevant information, and those which are not reporting an adverse drug reaction as “not relevant.” The review process is consisted of many rules and aspects which needed to be taken into consideration. Therefore, for the training of the algorithm, thousands of documents from previous screenings have been used. After several iterations of adjustments and fine tuning, the ML approach is definitively a great achievement in pre‐sorting the articles into “relevant” and “non‐relevant” and supporting the intellectual review process.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
Using machine learning (ML) to make decisions based on previous decisions is becoming more prominent in the digital world. However, to implement such a workflow in a very regulated field is a big challenge.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
To what extend is it possible to replace human decisions needing intellectual input by ML?
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
It shows that it is to a certain extent possible to detect drug safety‐related information to the drugs in focus in written text. Furthermore, it combines the methodologies to show which technical solutions are best.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
Using ML in more and more processes will gain efficiency and will make drug discovery, drug development, and postmarketing surveillance more efficient and, most importantly, it will increase the patients’ safety.  相似文献   
7.
Reddy VS  Phan HH  O'Neill JA  Neblett WW  Pietsch JB  Morgan WM  Cywes R 《The American surgeon》2001,67(9):859-63; discussion 863-4
The purpose of this study was to compare a recent contemporaneous experience between laparoscopic (LS) and open (OS) splenectomy in children. All splenectomy cases between 1994 and 1999 at our institution were reviewed. The study included open and laparoscopic cases performed according to surgeon preference. Emergency splenectomies for trauma were excluded. The patient record was reviewed for the diagnosis, indications, postoperative length of stay, operative technique, postoperative complications, blood loss/blood transfusion, total amount of parenteral narcotics, and time to resumption of oral intake. Chi-square and t tests were used to compare measured differences for statistical significance. Between May 1994 and December 1999, 52 splenectomies were performed at Vanderbilt Children's Hospital. Of these, 45 were elective operations with 29 open and 16 laparoscopic procedures. During four OS and five LS operations a concomitant cholecystectomy was performed. The median patient age was 9.2 years (range 0.5 to 17.3). There was no statistical difference between the two groups in terms of age, weight, American Society of Anesthesiologists class, or estimated blood loss. There were no immediate postoperative complications in either group. There were no conversions from LS to OS. The mean duration of surgery was 264 minutes (LS) versus 169 minutes (OS) (P < 0.05). The average time to first oral intake was shorter in patients undergoing LS (1.1 vs 1.6 days, P < 0.05) and the mean postoperative length of stay was also shorter in the LS group (1.3 vs 3.1 days, P < 0.05). The use of postoperative intravenous narcotics (in morphine-equivalent doses) was significantly less in LS patients than in OS patients (7.5 mg or 0.15 mg/kg vs 46.9 mg or 1.5 mg/kg, P < 0.001), as was the need for PCA pump analgesia (90% in the OS group vs 25% in LS group, P < 0.01). Overall the average hospital charge (anesthesia fee, narcotics charge, and hospital room charge) was $5400 (range $4240-6250) in the OS group and $4950 (range $4450-6240) in the LS group (P < 0.05). Among the nine patients undergoing splenectomy with cholecystectomy, findings between the OS and LS groups were similar except for one late complication consisting of a diaphragmatic hernia in an LS patient. Both LS and OS with or without a concomitant procedure can be accomplished safely in children. LS appears to result in longer operative times but shorter lengths of stay, earlier first oral intake, and significantly fewer requirements for intravenous narcotics; all of these contribute to a reduction in hospital charges compared with the open operation.  相似文献   
8.
Comparison of Celsior and UW solution in experimental pancreas preservation   总被引:10,自引:0,他引:10  
BACKGROUND: The University of Wisconsin solution (UW) is the gold standard for pancreas preservation. Celsior (CEL) was formulated specifically for heart preservation. Recently, experimental and clinical experience has been reported on the application of CEL to abdominal organs. In this animal study, pancreas preservation with CEL was compared with that in UW solution. PATIENTS AND MATERIALS: Heterotopic, allogeneic pancreaticoduodenal transplantation was performed in female G?ttingen Minipigs (n = 12 donors, n = 12 recipients). The grafts were flushed and stored for 6 h at 4 degrees C in UW or CEL. The recipients were randomized into two groups receiving either UW (n = 6)- or CEL (n = 6)-preserved grafts with a follow-up of 5 days. Blood flow (laser Doppler), partial oxygen tension, histological changes, endothelin-1 (plasma, immunohistochemistry), lipase, amylase, trypsinogen activation peptide, and C-reactive protein (CRP) were measured. RESULTS: Partial oxygen tension was lower in the CEL group (P < 0.05). However, blood flow did not differ between UW- and CEL-preserved organs. The histomorphologic analysis of the pancreatic grafts revealed significantly less edema in the UW-preserved organs. Serum levels of amylase, lipase, CRP, and TAP taken from the central venous blood were comparable in the two groups, except for higher amylase values 36 h after reperfusion in the CEL group compared to the UW group (P < 0.05). Likewise, TAP taken from the portal venous effluent of the graft was found to be higher in the CEL group than in UW (P < 0.05). Endothelin-1 serum levels rose significantly during reperfusion without differences between the two groups. ET-1 immunohistochemistry revealed increased local ET-1 during reperfusion in all grafts. However, the ET-1 immunostaining in the CEL group was more pronounced than that in the UW group (P < 0.05). CONCLUSIONS: Our results suggest that CEL solution is not as effective in preventing pancreatic ischemia/reperfusion damage as the standard UW solution in experimental pancreas transplantation. Increased ET-1 immunostaining and reduced p(ti)O(2) in the CEL group indicate increased microcirculatory damage in the CEL group.  相似文献   
9.
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states.  相似文献   
10.

Background  

Patients with diabetic polyneuropathy (DPN) are often confronted with ulceration of foot soles. Increased plantar pressure under the forefoot has been identified as a major risk factor for ulceration. This study sets out to test the hypothesis that changes in gait characteristics induced by DPN related muscle weakness are the origin of the elevated plantar pressures.  相似文献   
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