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排序方式: 共有1846条查询结果,搜索用时 31 毫秒
131.
UC Wieshmann GJ Barker MR Symms PA Bartlett JM Stevens SD Shorvon 《Canadian Metallurgical Quarterly》1998,40(8):483-489
Breast reconstruction has been the subject of many controversies. It now seems generally agreed however that the operation has no deleterious influence on the follow up of breast cancer patients and that it has favorable psychologic effects. Breast reconstruction can be performed either by using prostheses or analogous tissues. These two different modalities have each their own advantages and limitations. Deep knowledge of the techniques and their indications allows to select the most appropriate approach in the individual patient and, thus, to improve long term results. 相似文献
132.
A bee sting can cause a foreign body granuloma of the skin, due to activated macrophages at the stinging site. A 52-year-old woman presented with a large doughnut-shaped ulcerative tumour on the left side of her face. A bean-sized facial papule had grown to a 4.0 x 3.9 x 1.1 cm mass after multiple bee stings induced by herself over a period of 1 year. Histology showed epidermal ulceration with granulomatous inflammatory cell infiltration of many eosinophils. No micro-organisms or foreign bodies were identified. Intralesional triamcinolone acetonide was not effective, but an excellent outcome was obtained using carbon dioxide laser vaporization of the lesion. 相似文献
133.
LI Bruijn MK Houseweart S Kato KL Anderson SD Anderson E Ohama AG Reaume RW Scott DW Cleveland 《Canadian Metallurgical Quarterly》1998,281(5384):1851-1854
Analysis of transgenic mice expressing familial amyotrophic lateral sclerosis (ALS)-linked mutations in the enzyme superoxide dismutase (SOD1) have shown that motor neuron death arises from a mutant-mediated toxic property or properties. In testing the disease mechanism, both elimination and elevation of wild-type SOD1 were found to have no effect on mutant-mediated disease, which demonstrates that the use of SOD mimetics is unlikely to be an effective therapy and raises the question of whether toxicity arises from superoxide-mediated oxidative stress. Aggregates containing SOD1 were common to disease caused by different mutants, implying that coaggregation of an unidentified essential component or components or aberrant catalysis by misfolded mutants underlies a portion of mutant-mediated toxicity. 相似文献
134.
EW Steyerberg HJ Keizer SD Foss? DT Sleijfer GC Toner H Schraffordt Koops PF Mulders JE Messemer K Ney JP Donohue 《Canadian Metallurgical Quarterly》1995,13(5):1177-1187
PURPOSE: To develop a statistical model that predicts the histology (necrosis, mature teratoma, or cancer) after chemotherapy for metastatic nonseminomatous germ cell tumor (NSGCT). PATIENTS AND METHODS: An international data set was collected comprising individual patient data from six study groups. Logistic regression analysis was used to estimate the probability of necrosis and the ratio of cancer and mature teratoma. RESULTS: Of 556 patients, 250 (45%) had necrosis at resection, 236 (42%) had mature teratoma, and 70 (13%) had cancer. Predictors of necrosis were the absence of teratoma elements in the primary tumor, prechemotherapy normal alfa-fetoprotein (AFP), normal human chorionic gonadotropin (HCG), and elevated lactate dehydrogenase (LDH) levels, a small prechemotherapy or postchemotherapy mass, and a large shrinkage of the mass during chemotherapy. Multivariate combination of predictors yielded reliable models (goodness-of-fit tests, P > .20), which discriminated necrosis well from other histologies (area under the receiver operating characteristic (ROC) curve, .84), but which discriminated cancer only reasonably from mature teratoma (area, .66). Internal and external validation confirmed these findings. CONCLUSION: The validated models estimate with high accuracy the histology at resection, especially necrosis, based on well-known and readily available predictors. The predicted probabilities may help to choose between immediate resection of a residual mass or follow-up, taking into account the expected benefits and risks of resection, feasibility of frequent follow-up, the financial costs, and the patient's individual preferences. 相似文献
135.
Most patients in acute myocardial infarction (AMI) undergo emergent coronary angiography (CAG). However, when to analyze lipoprotein profiles in AMI is not clear. To determine whether lipoprotein profiles change during catheterization, we measured serum lipid and apolipoprotein concentrations in 65 patients (51 men and 14 women) before and after catheterization. Heparin was injected at 50 units/kg for CAG and 200 units/kg for percutaneous transluminal coronary angioplasty (PTCA). We found that cholesterol and triglyceride decreased by 9.4% (P < 0.001) and 53.1% (P < 0.001), respectively, after catheterization. Apolipoproteins also decreased significantly. Variables decreased two to five times more after PTCA than after CAG. Lipoprotein lipase mass was higher after PTCA (267.8 +/- 135.3 micrograms/L) than after CAG (93.3 +/- 48.4 micrograms/L; P < 0.05). In conclusion, lipoprotein profiles change during catheterization. We recommend avoiding analysis of lipoprotein profiles after emergent CAG in AMI. 相似文献
136.
SD Brown 《Canadian Metallurgical Quarterly》1998,4(4):567-82, vii
Acute respiratory distress syndrome (ARDS) was formally described in 1971; however, physicians have been describing this syndrome and associating pulmonary edema with sepsis or toxic origins for over 100 years. Recently, an international conference accepted definitional criteria for ARDS that have become the accepted standard. ARDS is triggered by a large number of insults that often do not directly affect the lung. ARDS progresses pathologically through exudative, proliferative, and fibrotic phases. 相似文献
137.
SD Passik RK Portenoy PL Ricketts 《Canadian Metallurgical Quarterly》1998,12(5):729-34; discussion 736, 741-2
The relationship between the therapeutic use of potentially abusable drugs for symptom control and the multifaceted nature of abuse and addiction is extremely complex. Research is only beginning to elucidate the nature of this relationship and its clinical implications. At present, practical management is based primarily on clinical experience and anecdotal observations. In part I of this two-part series (published last month), the authors explored the epidemiology of substance abuse in the cancer population, provided definitions of addiction and abuse appropriate for the oncology setting, and offered guidelines for the assessment of aberrant drug-taking behavior. In this second part, the authors provide recommendations for the evaluation and treatment of patients with cancer who have a history of substance abuse. Suggested therapeutic goals are outlined, and plans for inpatient and outpatient management and detailed. 相似文献
138.
Hapalotrema mehrai Rao, 1976 and Hapalotrema postorchis Rao, 1976 (Digenea: Spirorchidae) are redescribed from the heart and pulmonary arteries of the green turtle, Chelonia mydas, from Moreton Bay in south-eastern Queensland. Hapalotrema pambanensis Gupta and Mehrotra, 1981 from C. mydas in India is made a synonym of H. mehrai. Hapalotrema dorsopora Dailey, Fast and Balazs, 1993 from C. mydas from Hawaii was described with a dorsally opening uterine pore, but this is found to be the opening of Laurer's canal; therefore H. dorsopora is also made a synonym of H. mehrai. In addition to differences in the numbers of testes and general dimensions, H. mehrai and H. postorchis differ in the development of Laurer's canal and in the absence of a canalicular seminal receptacle in H. postorchis. 相似文献
139.
Our objective was to determine whether methotrexate is an effective steroid-sparing agent for patients with severe asthma. Published reports of controlled trials assessing the use of methotrexate in asthma were identified by a search of the MEDLINE, EMBASE, CINAHL, Biological Abstracts on CD, and Current Contents databases. Bibliographies from identified studies and from review articles were manually searched. Published and unpublished reports in any language were identified and assessed for inclusion in the meta-analysis. We selected randomized, double-blind, placebo-controlled trials in which low-dose methotrexate was administered to corticosteroid-dependent asthmatics, and oral steroids were subsequently tapered according to the patients' clinical status. Data were extracted independently by two reviewers. For all eligible trials, the mean reduction in oral corticosteroid dose, the mean change in FEV1, and the standard deviations, were calculated for the treatment and control groups. Data concerning side-effects of therapy were also extracted. Data from 12 studies, reporting on a total of 250 patients, were pooled using a weighted average method, with weights proportional to the inverse of the variance of the treatment effect. Compared to placebo, the use of methotrexate was associated with a pooled 6.0% improvement in FEV1 (95% CI, 1.0-11%) and an 18.2% reduction in oral steroid use (95% CI, 11.7-24.7%). This corresponded to a 3.3 mg day-1 greater reduction in oral steroid use for patients taking methotrexate than for those taking placebo (95% CI, 2.1-4.4 mg day-1). Gastrointestinal complications and transient increases in liver enzymes were more common in patients randomized to methotrexate. Three potentially life-threatening side-effects (two pneumonias and one liver dysfunction) occurred in 159 patients randomized to methotrexate vs. none in those patients on placebo. It was concluded that methotrexate allowed a modest reduction in oral corticosteroid compared to patients receiving placebo. The benefit is relatively small, however, and should be balanced against the potential for side-effects associated with the use of methotrexate. 相似文献
140.
CS Dolman BM Mueller HN Lode R Xiang SD Gillies RA Reisfeld 《Canadian Metallurgical Quarterly》1998,4(10):2551-2557
Immunocytokines are antibody-cytokine fusion proteins that combine the unique targeting ability of antibodies with the multifunctional activities of cytokines to activate effector cells in the tumor microenvironment. Here, we demonstrate the therapeutic efficacy of a tumor-specific immunocytokine, huKS1/4-IL2, which effectively inhibited growth and dissemination of lung and bone marrow metastases of human prostate carcinoma in severe combined immunodeficient mice. This antitumor effect was specific and highly effective, irrespective of reconstitution of these mice with human lymphokine-activated killer cells. Survival times of mice treated with huKS1/4-IL2 were increased 4-fold as compared with animals treated with a mixture of the corresponding antibody and recombinant human interleukin-2 (rhIL2). A persistent antitumor response after treatment with the huKS1/4-IL2 immunocytokine in B, T, and natural killer cell-deficient severe combined immuodeficient-BEIGE mice, depleted of granulocytes, implies a major role for macrophages in this treatment effect. Our data demonstrate that immunocytokine-directed interleukin-2 therapy to tumor sites is an immunotherapeutic approach with potent effects against disseminated metastases of human prostate carcinoma and suggest that this treatment could be effective in an adjuvant setting for patients with minimal residual disease. 相似文献