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31.
Background Merkel cell carcinoma (MCC) is a rare malignant cutaneous tumour, the incidence of which is increasing. Second malignancies have been reported to occur with high incidence in these patients. Objectives We report the rate and nature of multiple malignancies in patients with MCC treated over a 10 year period in Addenbrooke’s Hospital in Cambridge, United Kingdom, as well as the temporal relationship of these additional malignancies to the diagnosis of MCC. Results The 27 patients had an approximately equal sex incidence with a median age at diagnosis of 79 years. Seventy percent (n=19) of patients had a second primary malignant tumour; and 7 of these patients had two or more tumours in addition to the MCC. Eighteen patients had additional cutaneous malignancies: melanoma, squamous cell carcinoma and basal cell carcinoma, and 8 patients presented non‐cutaneous malignancy including colorectal, haematological and breast tumours. Of the 28 additional tumours in our patients, half were diagnosed prior to presentation of MCC, 32% within 6 months of diagnosis, and 18% between 6 months and 3 years after diagnosis. Possible reasons for the high rate of additional tumours in this population are discussed. Conclusions Our figures reflect a higher incidence of multiple malignancies in those with Merkel cell tumour than has previously been reported. This has important implications for the care and surveillance of these patients.  相似文献   
32.
Stomach erosion after gastric banding represents one of its least studied complications, despite the fact that the modalities of presentation and treatment have been clarified in recent years. Associations between this complication and specific surgical factors related to the patient have not been reported. We evaluated the incidence of this complication in various operating environments, to identify a possible association with a specific risk factor. A total of 250 patients underwent gastric banding between 2006 and 2008 and were followed for at least 1 year of follow-up. The procedure was performed in three Centers by the same surgical team. Center A was selected for the learning curve, in the initial phase of the study. All surgeries were performed with standardized techniques. An annual endoscopic evaluation was performed during first 12 months. The data from the three Centers were evaluated comparatively, to assess the incidence of migration and compare sterilization and perioperative preparation techniques. Between May 2006 and December 2008, 140 patients operated on at Center A, 70 at Center B, and 50 at Center C were included. Twelve cases of intragastric migration were observed (4.8% of the entire cohort): two cases at Center A (1.4%) and 10 cases at Center C (25%; A vs. C and A vs. B, p?<?0.05); no cases of erosions were observed in Center B of 50 patients (0%; reviewer 1, comment 1). From a retrospective observation, no significant difference in sterilization techniques was observed, while there were differences in perioperative preparation, although these are not objectifiable parameters.  相似文献   
33.
Objective:   The aim of the present work was to measure the pain threshold in hypertensive patients with a new auto-algometry method.
Design and Setting:   Auto-algometry consists of asking the subjects to push their fingers against a fixed round-tip needle until they feel a pain sensation. An electronic force transducer permits the measurement of the force applied by the subjects and storage of the data on a personal computer. Eight tests are performed twice on each subject on the tip and back of four fingers. For each test, the maximal applied force (grams) is defined as pain threshold. The overall discomfort during the entire procedure is reported by the subjects on a 0 (no discomfort) to 10 (intolerable pain) scale.
Patients and Interventions:   A group of hypertensive patients ( n  = 22) and a group of normotensive subjects ( n  = 22) underwent the auto-algometry examination.
Results:   The pain threshold was higher in hypertensive patients compared with normotensive subjects. All discomfort scores referred by the subjects fell within the 4–6 range.
Conclusion:   The data obtained from this study indicate that the auto-algometer as described here can detect hypoalgesia associated with hypertension.  相似文献   
34.
BACKGROUND AND PURPOSE: Inclusion of oligodendroglial tumors may confound the utility of MR based glioma grading. Our aim was, first, to assess retrospectively whether a histogram-analysis method of MR peifusion images may both grade gliomas and differentiate between low-grade oligodendroglial tumors with or without loss of heterozygosity (LOH) on 1p/19q and, second, to assess retrospectively whether low-grade oligodendroglial subtypes can be identified in a population of patients with high-grade and low-grade astrocytic and oligodendroglial tumors.  相似文献   
35.
Monda LA 《Radiologic technology》2002,74(1):46-68; quiz 69-72
After completing this article on mammographic processing, readers will: Understand the relationship between mammography and breast cancer survival. Define quality assurance and quality control. Discuss the history of the Mammography Quality Standards Act. List the important considerations in processor setup. Name the tests in the medical physicist survey. Know how to perform daily processor quality control. Understand the importance of continuous quality improvement.  相似文献   
36.
37.
Since the posterior hypothalamus (PH) plays a key role in the control of body temperature, the aim of this study was to evaluate the changes in adrenaline, noradrenaline and dopamine levels in the PH during the hyperthermia induced by prostaglandin E(1) (PGE(1)). The concentration of adrenaline, noradrenaline and dopamine in the PH, the firing rate of the sympathetic nerves innervating interscapular brown adipose tissue (IBAT), IBAT and colonic temperatures (T(IBAT) and T(C)) were monitored in 12 urethane-anaesthetized male Sprague-Dawley rats before and after an intracerebroventricular injection of 500 ng PGE(1) dissolved in 2 microl of 0.9% NaCl saline solution or only saline. The catecholamines were collected using a microdialysis probe and quantified by HPLC. The results showed that PGE(1) caused a significant increment in the concentration of adrenaline from 15. 83+/-2.69 to 34.95+/-3.9 ng ml(-1) and of dopamine from 35.15+/-4.48 to 55.68+/-6.21 ng ml(-1). A significant decrease in the level of noradrenaline from 18.75+/-2.05 to 8.56+/-2.26 ng ml(-1) was registered. The firing rate of sympathetic nerves to IBAT was increased from 100+/-0% to 204.83+/-15.22% by PGE(1). T(IBAT) and T(C) rose respectively from 36.91+/-0.15 degrees C to 38.88+/-0.29 degrees C, and from 36.7+/-0.15 degrees C to 38.13+/-0.36 degrees C after the injection of PGE(1). The changes in adrenaline and noradrenaline occurred during the first 20 min as did the changes in temperature and firing rate, while the change in dopamine was delayed until 21-60 min after the PGE(1) injection. No significant change of analyzed variables was found in the control rats. These findings suggest that these biogenic amines of the PH are involved in the control of the sympathetic and thermogenic changes induced by PGE(1).  相似文献   
38.
This experiment tested (i) the effect of orexin A injected into a lateral cerebral ventricle on sympathetic and thermogenic activity and (ii) the involvement of prostaglandins in these phenomena. The firing rates of the sympathetic nerves to interscapular brown adipose tissue (IBAT), along with IBAT and colonic temperatures and heart rate were monitored in urethane-anesthetized male Sprague-Dawley rats before and 6 h after an injection of orexin A (1.5 nmol) into the lateral cerebral ventricle. The same variables were monitored in rats with an intraperitoneal administration of lysine acetylsalicylate (100 mg/kg bw), an inhibitor of prostaglandins synthesis. The results show that orexin A increases the sympathetic firing rate, IBAT and colonic temperatures and heart rate. This increase is reduced by lysine acetylsalicylate. These findings suggest that orexin A affects sympathetic activity, which controls body temperature. Prostaglandins are involved in this control.  相似文献   
39.
5-Fluorouracil in combination with leucovorin has been shown to be active in therapeutic trials of metastatic colorectal carcinoma. In this study, we administered these drugs to 72 patients with metastatic colorectal carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36 patients with or without prior 5-fluorouracil treatment received 5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous infusion every two weeks. Clinical efficacy and toxicity were assessed by WHO criteria. Variables were tested for relations to response and survival by univariate and multivariate analysis. The response rate was 19.4% in weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527). Median survivals in the two arms were 18.4 months (weekly) and 21 months (biweekly) respectively (P = 0.708). Gastrointestinal side effects including nausea, vomiting, diarrhea and mucositia were the major toxicities of these regimens. By multivariate analysis, the only factor to influence response rate was the site of metastases (P = 0.009). The only factor to affect survival was performance status of the patient (P = 0.0001). We concluded that the two 5-fluorouracil based regimens are well-tolerated and shown to have a response rate comparable with previous reports of similar regimens in patients with metastatic colorectal cancer. Only liver metastases seemed to have a better response to therapy. Performance status is the most important prognostic factor in patients with metastatic colorectal cancer.   相似文献   
40.
Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant role in mediatingtat induced T-cell apoptosis.  相似文献   
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