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Increasing incidence of eczema herpeticum: analysis of seventy-five cases   总被引:1,自引:0,他引:1  
Clinicians at the Department of Dermatology at the University of Mainz saw 63 patients with 75 episodes of eczema herpeticum. An analysis of these cases shows an exceedingly high rate of increased incidence of the disease. From 1969 through 1981, 13 cases were registered, whereas in the years 1982 to 1986 the number of cases was 62. The mean age of the patients was 22.7 years, and 42 patients (56%) were between 15 and 24 years of age. This finding shows that the affected patients are not predominantly infants, as has been reported up to now. Of these patients 5 had one recurrence, two had two recurrences, and one had three recurrences. Acyclovir, used for treatment in 38 cases, led to rapid improvement, whereas therapy with immunoglobulins, antibiotics, and so-called immunostimulating agents did not clearly influence disease duration.  相似文献   
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The angiotensin AT2‐receptor is a main receptor of the protective arm of the renin‐angiotensin system. Understanding of this unconventional G‐protein coupled receptor has significantly advanced during the past decade, largely because of the availability of a selective non‐peptide AT2‐receptor agonist, which allowed the conduct of a multitude of studies in animal disease models. This article reviews such preclinical studies that in their entirety provide strong evidence for an anti‐fibrotic effect mediated by activation of the AT2‐receptor. Prevention of the development of fibrosis by AT2‐receptor stimulation has been demonstrated in lungs, heart, blood vessels, kidney, pancreas and skin. In lungs, AT2‐receptor stimulation was even able to reverse existing fibrosis. The article further discusses intracellular signalling mechanisms mediating the AT2‐receptor‐coupled anti‐fibrotic effect, including activation of phosphatases and subsequent interference with pro‐fibrotic signalling pathways, induction of matrix‐metalloproteinases and hetero‐dimerization with the AT1‐receptor, the TGF‐βRII‐receptor or the RXFP1‐receptor for relaxin. Knowledge of the anti‐fibrotic effects of the AT2‐receptor is of particular relevance because drugs targeting this receptor have entered clinical development for indications involving fibrotic diseases.  相似文献   
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Background In this multi-institutional prospective study, we evaluated whether we could identify risk factors predictive for non-sentinel lymph node (non-SN) metastases in breast cancer patients with a positive sentinel lymph node (SN). Methods In this multi-institutional study, 541 eligible breast cancer patients were included prospectively. Results The occurrence of non-SN metastases was related to the size of the SN metastasis (P = .02), primary tumor size (P = .001), and lymphovascular invasion (P = .07). The adjusted odds ratio was 3.1 for SN micro-metastasis compared with SN isolated tumor cells, 4.0 for SN macro-metastasis versus SN isolated tumor cells, 3.1 for tumor size (>3.0 cm compared with ≤3.0 cm), and 2.0 for lymphovascular invasion (yes versus no). There were no positive non-SNs when the primary tumor size was ≤1.0 cm (n = 24) [95% confidence interval (95% CI) 0%–14.0%]. The proportion of positive non-SNs ranged in a prognostic logistic regression model from 9.7% (95% CI 4.0%–23.0%) for patients with SN isolated tumor cells, tumor size of 1.1–3.0 cm, and without vessel invasion, to 72.6% (95% CI 47.0%–89.0%) for patients with SN macro-metastasis, tumor size >3.0 cm, and with vessel invasion. Conclusion We identified three predictive factors for non-SN metastases in breast cancer patients with a positive SN: size of the SN metastasis; primary tumor size; and vessel invasion. We were not able to identify a specific group of patients with a positive SN in whom the risk for non-SN metastases was less than 5%.  相似文献   
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Despite the high abundance of Archaea in the global ocean, their metabolism and biogeochemical roles remain largely unresolved. We investigated the population dynamics and metabolic activity of Thaumarchaeota in polar environments, where these microorganisms are particularly abundant and exhibit seasonal growth. Thaumarchaeota were more abundant in deep Arctic and Antarctic waters and grew throughout the winter at surface and deeper Arctic halocline waters. However, in situ single-cell activity measurements revealed a low activity of this group in the uptake of both leucine and bicarbonate (<5% Thaumarchaeota cells active), which is inconsistent with known heterotrophic and autotrophic thaumarchaeal lifestyles. These results suggested the existence of alternative sources of carbon and energy. Our analysis of an environmental metagenome from the Arctic winter revealed that Thaumarchaeota had pathways for ammonia oxidation and, unexpectedly, an abundance of genes involved in urea transport and degradation. Quantitative PCR analysis confirmed that most polar Thaumarchaeota had the potential to oxidize ammonia, and a large fraction of them had urease genes, enabling the use of urea to fuel nitrification. Thaumarchaeota from Arctic deep waters had a higher abundance of urease genes than those near the surface suggesting genetic differences between closely related archaeal populations. In situ measurements of urea uptake and concentration in Arctic waters showed that small-sized prokaryotes incorporated the carbon from urea, and the availability of urea was often higher than that of ammonium. Therefore, the degradation of urea may be a relevant pathway for Thaumarchaeota and other microorganisms exposed to the low-energy conditions of dark polar waters.  相似文献   
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J Oral Pathol Med (2010) 39 : 786–792 Background: Vascular endothelial growth factor (VEGF) plays an important role in promoting angiogenesis and is overexpressed in several malignancies. Polymorphisms of the VEGF gene can alter VEGF protein expression, which may be biologically significant and account for heterogeneity in disease risk and outcome. The aim of this case–control study was to evaluate potential associations between single nucleotide polymorphisms (SNP) of the VEGF gene with susceptibility of oral squamous cell carcinoma (OSCC). Patients and methods: Five VEGF SNP (?1154 G/A, +405 G/C, +936 C/T, ?2578 C/A and ?460 C/T) were determined in peripheral blood isolated from 80 patients with OSCC and from 40 age‐ and gender‐matched healthy volunteers (RT‐PCR). Results: The +936 T allele and the ?2578 C/A SNP were expressed significantly more often in the OSCC‐group (P = 0.002; P < 0.0001) where three associations between two SNPs (+936 and +405, ?2578 and ?1154, ?460 and ?2578) were found. Conclusion: Our findings provide support that +936 T allele and ?2578 C/A SNP of the VEGF gene alone or in combination with other SNP are associated with OSCC. The SNPs may be used as biomarker for the development of specialized anti‐VEGF drugs. Further studies must confirm the value of preoperative genetic analysis for prognosis.  相似文献   
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