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排序方式: 共有643条查询结果,搜索用时 15 毫秒
1.
Lymphocytic adenohypophysitis of pregnancy with complete recovery   总被引:1,自引:0,他引:1  
A case of lymphocytic adenohypophysitis in a postpartum woman who became symptomatic during her 8th month of pregnancy is presented. The clinical presentation, endocrine findings, pathological findings, and operative management are discussed. Transient hypopituitarism is documented. Unlike most previously published cases, this woman had complete recovery of anterior pituitary function.  相似文献   
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We describe the case of a recipient of an implantable cardioverter defibrillator with multiple syncopal episodes due both to superior vena cava obstruction and electrical instability. These complications occurred in the presence of two transvenous implantable cardioverter defibrillator leads. The patient has been managed conservatively with anticoagulants and new antiarrhythmic drugs with improvement in both his clinical problems.  相似文献   
4.
Tumour angiogenesis: vascular growth and survival   总被引:3,自引:0,他引:3  
Angiogenesis starts at the edge of a malignant epithelial tumour concurrently with tumour cell invasion and stromatogenesis, i.e. the formation of specific connective tissue stroma amenable to easy penetration by endothelial and tumour cells. However, as the tumour continues its growth, the edge becomes the inner tumour area, and a new invading tumour front is formed by the multiplying malignant cells which outflank the initial edge. This process, which repeats itself again and again, forms the "relay race" model of tumour vascular growth and regression. At the heart of the tumour unfavourable environmental conditions prevail -- hypoxia, acidity, lack of nutrients, failure of waste removal, and apoptosis rather than proliferation. Blood vessels and tumour cells are greatly decreased, but do not vanish, as tumour cells are shifting to anaerobic glycolysis, and blood vessels are turning into anti-apoptotic pathways -- vascular survival ability (VSA). Thus, assessing vascular density (VD) by simply counting "hot spots" at the edge of a tumour, where conditions are most favourable, is futile; it may reflect tumour angiogenic activity (TAA), but is not representative of genuine tumour vasculature. By combining vessel counts at the invading tumour front with those of the inner tumour areas a complete picture of tumour VD can be achieved. The thus formed four patterns of vascularization, designated as "edvin" (edge vsinner tumour area), are: edvin 1: low TAA/low VSA; edvin 4: high TAA/high VSA; edvin 2: low TAA/high VSA; and edvin 3: high TAA/low VSA. It is expected that this scheme will prove useful in the field of chemoradiotherapy and anti-angiogenic treatment.  相似文献   
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c-erbB-2-positive breast carcinomas are highly aggressive tumors. In vitro data on breast cell lines showed that c-erbB-2 enhanced translational efficiency of hypoxia inducible factor-1alpha (HIF1alpha) production (Laughner et al., Mol Cell Biol 2001;21:3995-4005). We investigated the clinical correlate of this observation to assess whether c-erbB-2 expression was related to HIF1alpha expression, angiogenesis, and prognosis. A series of 180 breast carcinomas of known c-erbB-2 status (90 c-erbB-2-positive and 90 c-erbB-2-negative carcinomas) were stained immunohistochemically for HIF1alpha and CD31 endothelial cell antigen. c-erbB-2 positivity was clearly related to HIF1alpha protein expression and high angiogenesis. However, prognosis was decreased only in cases with simultaneous c-erbB-2 and HIF1alpha expression. If activation of c-erbB-2 in humans results in overexpression of HIF1alpha independently of conditions of hypoxia, as occur in experimental studies, this interaction may represent a main pathway conferring clinical aggressiveness to c-erbB-2-positive breast tumors.  相似文献   
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BACKGROUND: Waldenstrom's macroglobulinemia (WM) is an unusual lymphoplasmacytoid lymphoma characterized by the presence of a serum monoclonal immunoglobulin M. Although several studies have evaluated possible prognostic factors of this disease, few have focused on the survival and prognosis of symptomatic patients after the initiation of treatment. PATIENTS AND METHODS: Our study included 122 previously untreated patients with a median age of 67 years who required systemic treatment. Multiple variables were analyzed for their prognostic value on survival after initiation of treatment using univariate and Cox regression multivariate analysis. RESULTS: The median overall survival was 106 months. Pretreatment factors associated with shorter survival were age >/=65 years, splenomegaly, B-symptoms (weight loss, fever or night sweats), hemoglobin <10 g/dl, platelets <100 x 10(6)/dl, albumin <3.5 g/dl and bone marrow lymphoplasmacytic infiltrate >/=50%. In the multivariate analysis, the two variables with independent prognostic value were age >/=65 years and hemoglobin <10 g/dl. Furthermore, we were able to divide our patients into three risk groups based on the presence of two, one or none of these two adverse prognostic factors. The median survival times in the high-, intermediate- and low-risk groups were 46 months, 107 months and 172 months, respectively (P <0.0001). DISCUSSION: Our findings suggest that advanced age and anemia appear to be the two dominant prognostic factors for survival after initiation of treatment in patients with WM. These two readily available parameters can stratify the patients into three distinct subgroups and may help the selection of appropriate treatment.  相似文献   
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Although foreign bodies left in the abdominal cavity may remain asymptomatic for long periods, they may also cause serious complications. We present a case of gauze forgotten in the lower abdomen which remained asymptomatic for almost 1 year. When a granuloma had formed, it infiltrated the bladder wall giving the clinical and imaging appearance of an invasive bladder tumor.  相似文献   
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Using the recently proposed Susceptible–Asymptomatic–Infected–Vaccinated–Removed (SAIVR) model, we study the impact of key factors affecting COVID-19 vaccine rollout effectiveness and the susceptibility to resurgent epidemics. The SAIVR model expands the widely used Susceptible–Infectious–Removed (SIR) model for describing epidemics by adding compartments to include the asymptomatic infected (A) and the vaccinated (V) populations. We solve the model numerically to make predictions on the susceptibility to resurgent COVID-19 epidemics depending on initial vaccination coverage, importation loads, continuing vaccination, and more contagious SARS-CoV-2 variants, under persistent immunity and immunity waning conditions. The parameters of the model represent reported epidemiological characteristics of the SARS-CoV-2 virus such as the disease spread in countries with high levels of vaccination coverage. Our findings help explain how the combined effects of different vaccination coverage levels and waning immunity lead to distinct patterns of resurgent COVID-19 epidemics (either surges or endemic), which are observed in countries that implemented different COVID-19 health policies and achieved different vaccinated population plateaus after the vaccine rollouts in the first half of 2021.  相似文献   
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The aim of the current study was to investigate whether a Total Lifestyle Index (TLI), including adherence to the Mediterranean diet, sleep duration, physical activity and engagement in activities of daily living, is associated with cognitive health over time and dementia risk, in a representative cohort of older people. A total of 1018 non-demented community-dwelling older adults ≥65 years old (60% women) from the HELIAD study were included. A comprehensive neurological and neuropsychological assessment was conducted at baseline and at the 3-year follow-up evaluating cognitive functioning, and a dementia diagnosis was set. Diet, physical activity, sleep duration and engagement in activities of daily living were assessed using standard, validated questionnaires at baseline. Sixty-one participants developed dementia at follow-up; participants who developed dementia were older and had fewer years of education compared with participants with normal cognition. With the exception of sleep duration, participants with normal cognition at follow-up scored higher in the individual lifestyle factors compared to those who developed dementia. Regarding TLI, values were lower for participants with dementia compared with those with normal cognition. Each additional unit of the TLI was associated with 0.5% of a standard deviation less decline per year of the Global Cognition score, whereas for each additional unit of the TLI, the risk for dementia was reduced by 0.2% per year (p < 0.05). Our results suggest that greater adherence to a healthy lifestyle pattern is associated with a slower decline of cognitive function and reduced dementia risk.  相似文献   
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