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Tumor vascularity has been proposed as a prognostic indicator for a number of solid tumors. Although a correlation between microvessel number and metastatic behavior has also been suggested for cutaneous melanoma, the small number of cases studied to date allows one to draw only preliminary conclusions. In this study, we have assessed tumor vascularity in cutaneous melanoma by comparing 60 cases of metastasizing and non-metastasizing tumors matched for tumor thickness, age, sex, and anatomic site. Ulex europaeus agglutinin I appeared to be the most suitable vascular marker for this study. Our results indicate that there was no statistically significant difference between the two groups with regard to tumor vascularity. Even after identifying 15 cases of thin (<1.0 mm thick) melanoma, there was no significant difference in the number of microvessels between metastasizing and non-metastasizing tumors. Comparison of patterns of vascular microarchitecture also failed to discriminate between the two groups. Thus, our results indicate that tumor vascularity may not be an independent prognostic factor for cutaneous melanoma.  相似文献   
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Background Are follicles where no oocytes are retrieved empty follicles?Methods The levels of estradiol (E2), progesterone (P), testosterone (T), cortisol (F), and prolactin (PRL) of follicular fluids (FF) aspirated individually from 34 randomly selected IVF patients in whom no oocytes were recovered were compared with the respective hormone levels of FF obtained from the same patients when oocytes were retrieved. Two FF without oocytes of a 35th patient in whom no oocytes were retrieved were analyzed.Results Hormones did not differ significantly in the paired samples, while in the two FF of the 35th woman they were in agreement with cystic follicles.Conclusions It is necessary to differentiate aspirated follicles where no oocytes are retrieved from the empty follicle syndrome, which was not observed in the IVF series studied and should be rare in IVF patients.  相似文献   
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Background  

Nonalcoholic fatty liver disease is one of the most prevalent forms of chronic liver disease in the Western world. Taurine is a conditionally essential amino acid in humans that may be a promising therapy for treating this disease.  相似文献   
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Macrophages that are recruited to the site of implanted biomaterials undergo fusion to form surface-damaging foreign body giant cells. Exposure of peripheral blood monocytes to interleukin-4 can recapitulate the fusion process in vitro. In this study, we used interleukin-4 to induce multinucleation of murine bone marrow-derived macrophages and observed changes in cell shape, including elongation and lamellipodia formation, before fusion. Because cytoskeletal rearrangements are regulated by small GTPases, we examined the effects of inhibitors of Rho kinase (Y-32885) and Rac activation (NSC23766) on fusion. Y-32885 did not prevent cytoskeletal changes or fusion but limited the extent of multinucleation. NSC23766, on the other hand, inhibited lamellipodia formation and fusion in a dose-dependent manner. In addition, we found that in control cells, these changes were preceded by Rac1 activation. However, NSC23766 did not block the uptake of polystyrene microspheres. Likewise, short interfering RNA knockdown of Rac1 limited fusion without limiting phagocytosis. Thus, phagocytosis and fusion can be partially decoupled based on their susceptibility to NSC23766. Furthermore, poly(ethylene-co-vinyl acetate) scaffolds containing NSC23766 attenuated foreign body giant cell formation in vivo. These observations suggest that targeting Rac1 activation could protect biomaterials without compromising the ability of macrophages to perform beneficial phagocytic functions at implantation sites.  相似文献   
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Botryosphaeria panicle and shoot blight was considered as one of the single greatest threats to the California pistachio industry in the last two decades. A large number of fungi with typical morphological characteristics of Botryosphaeriaceae and Diaporthe were collected from pistachios in 18 counties in California and deposited in our culture collection. The aims of this study were to identify these isolates, recognize the distribution of these fungal species and test their pathogenicity to pistachio cultivars. A total of 304 California isolates were identified based on comparisons of DNA sequence data of the ITS, TEF-1α and β-tubulin gene regions, and combined with the morphological features of the cultures and conidia. Research results showed that California isolates represent eight species of Botryosphaeriaceae and one species of Diaporthe. These species include Botryosphaeria dothidea, Diplodia seriata, Dothiorella iberica, Dot. sarmentorum, Lasiodiplodia citricola, L. gilanensis, Neofusicoccum mediterraneum, Neof. vitifusiforme and Diaporthe chamaeropis. Of the Botryosphaeriaceae, 86 % of the isolates were identified as Neof. mediterraneum, which distributed in all the sampled counties. On pistachio trees, in addition to isolates from California, Neof. mediterraneum from Arizona, Neof. australe from Australia, B. dothidea, Neof. parvum and Dia. viticola from Greece were also identified. Pathogenicity of the California fungi on pistachio cultivars, Kerman (female) and Peters (male), using a mycelium plug and conidial suspension inoculation methods showed that all these species are pathogenic to the two tested pistachio cultivars, with L. citricola, L. gilanensis being the most pathogenic species, followed by Neof. mediterraneum. This study represents the first comprehensive work on the species identification, distribution and pathogenicity of Botryosphaeriaceae and Diaporthe on pistachio in California.  相似文献   
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OBJECTIVE: This study compared three methods of assessing malnutrition in cirrhotics and correlated nutritional status with clinical outcome. METHODS: This cross-sectional study evaluated nutritional status by subjective global assessment (SGA), prognostic nutritional index (PNI), and handgrip strength (HG) in outpatients with cirrhosis (n = 50) and two control groups with hypertension (n = 46) and functional gastrointestinal disorders (n = 49). Patients with cirrhosis were followed for 1 y to verify the incidence of major complications, the need for transplantation, and death. RESULTS: Among patients with cirrhosis, 88% were Child-Pugh A and only 12% were Child-Pugh B. Among these, prevalences of malnutrition were 28% by SGA, 18.7% by PNI, and 63% by HG (P < 0.05). HG, but not SGA or PNI, predicted a poorer clinical outcome in patients with cirrhosis because major complications such as uncontrolled ascites, hepatic encephalopathy, spontaneous bacterial peritonitis, and hepatorenal syndrome developed in 65.5% of malnourished patients versus 11.8% of well-nourished ones (P < 0.05). No significant differences by any method were seen between the two groups regarding liver transplantation or death. CONCLUSIONS: There was a high prevalence of malnutrition in cirrhotic outpatients, especially when assessed by HG, which was superior to SGA and PNI in this study. HG was the only technique that predicted a significant incidence of major complications in 1 y in undernourished cirrhotic patients.  相似文献   
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