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31.
The water-soluble glucan was obtained from Pleurotus florida fruit bodies by hot water extraction, ethanol precipitation, DEAE cellulose dialysis and Sephadex G-75 gel filtration. The structural information of the glucan was achieved by chemical (hydrolysis, methylation, periodate oxidation) and spectroscopic (1H and 13C) analyses, indicated a repeating unit built up of (1→6)-linked D-glucose. The following structure has been determined for the repeating unit: →6)-α-D-Glcp-(1→ This fraction exhibited significant macrophage activity through the release of nitric oxide  相似文献   
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There is a paucity of robust clinical trial data to guide the treatment of acute pulmonary embolism (PE) thus the clinical guidelines rely heavily on expert opinion. Pulmonary Embolism Response Teams (PERT) have been developed to streamline the care of patients with acute PE. We conducted a survey among 100 experts in the field of PE during the second annual meeting of the PERT Consortium. Respondents were queried with respect to their demographic information, clinical practice questions and clinical vignettes. Clinical practice questions were focused questions about the risk stratification and treatment of patients with acute submassive PE, anticoagulation strategies for patients receiving thrombolysis and the use of inferior vena cava filters. Clinical vignettes were designed to assess participants’ preferred choice of treatment for a variety of commonly encountered clinical scenarios. Among physicians affiliated with a PERT, there is overall agreement with regards to the criteria used for risk classification of patients with PE and its application to patients in the provided clinical vignettes. In contrast, there is substantial variability in the treatment strategies of patients presenting with commonly encountered clinical scenarios. The results of this survey highlight the need for more clinical trial data along with accepted algorithms for treatment of acute PE. In the absence of this, PERTs can facilitate multidisciplinary discussions in order to standardize treatment and provide evidence-based therapies to patients with acute PE.  相似文献   
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There is a well‐documented shortage of physician researchers, and numerous training programs have been launched to facilitate development of new physician scientists. Short‐term research training programs are the most practical form of research exposure for most medical students, and the summer between their first and second years of medical school is generally the longest period they can devote solely to research. The goal of short‐term training programs is to whet the students’ appetite for research and spark their interest in the field. Relatively little research has been done to test the effectiveness of short‐term research training programs. In an effort to examine short‐term effects of three different NIH‐funded summer research training programs for medical students, we assessed the trainees’ (N = 75) research self‐efficacy prior to and after the programs using an 11‐item scale. These hands‐on training programs combined experiential, didactic, and mentoring elements. The students demonstrated a significant increase in their self‐efficacy for research. Trainees’ gender, ranking of their school, type of research, and specific content of research project did not predict improvement. Effect sizes for different types of items on the scale varied, with the largest gain seen in research methodology and communication of study findings.  相似文献   
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Purpose: To describe the clinical features, treatment, and outcomes of conjunctival melanoma in Asian Indians.

Methods: Retrospective study of 42 patients.

Results: The mean age at presentation of conjunctival melanoma was 43 years (median, 45 years; range, 9–78 years). There were 20 (48%) males and 22 (52%) females. Nineteen patients (45%) had a known history of a preexisting pigmented conjunctival lesion. Bulbar conjunctiva (n = 28; 67%) was the most common tumor epicenter, and medial ocular surface quadrant (n = 15; 36%) was more commonly involved. The mean tumor basal diameter was 12 mm (median, 10 mm; range, 4–30 mm), and the mean tumor thickness was 4 mm (median, 2 mm; range, 1–30 mm). Majority of the patients had a pigmented tumor (n = 33; 79%). The tumors arose de novo (n = 17, 41%) or were associated with conjunctival nevus (n = 9; 21%) or primary acquired melanosis (n = 16, 38%). Wide excisional biopsy, adjunctive cryotherapy, and amniotic membrane grafting were performed in 27 (71%) patients, 11 (29%) underwent orbital exenteration, and 4 were lost to follow-up prior to definitive treatment. Over a mean follow-up period of 24 months (median, 9 months; range, <1 to 136 months), four (11%) patients had tumor recurrence, seven (18%) had locoregional lymph node metastasis, and four (11%) developed systemic metastasis and died due to metastatic disease.

Conclusion: Conjunctival melanoma predominantly occurs in middle-aged Asian Indians and is associated with a high rate of systemic metastasis and death.  相似文献   

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Singh  J.  Cerghet  M.  Poisson  L. M.  Datta  I.  Labuzek  K.  Suhail  H.  Rattan  R.  Giri  Shailendra 《Journal of neuroimmune pharmacology》2019,14(2):241-250

Identification of non-invasive biomarkers of disease progression in multiple sclerosis (MS) is critically needed for monitoring the disease progression and for effective therapeutic interventions. Urine is an attractive source for non-invasive biomarkers because it is easily obtained in the clinic. In search of a urine metabolite signature of progression in chronic experimental autoimmune encephalomyelitis (EAE), we profiled urine at the chronic stage of the disease (day 45 post immunization) by global untargeted metabolomics. Using a combination of high-throughput liquid-and-gas chromatography with mass spectrometry, we found 105 metabolites (P < 0.05) significantly altered at the chronic stage, indicating a robust alteration in the urine metabolite profile during disease. Assessment of altered metabolites against the Kyoto Encyclopedia of Genes and Genomes revealed distinct non-overlapping metabolic pathways and revealed phenylalanine-tyrosine and associated metabolism being the most impacted. Combined with previously performed plasma profiling, eight common metabolites were significantly altered in both of the biofluids. Metaboanalyst analysis of these common metabolites revealed that phenylalanine metabolism and Valine, leucine, and isoleucine biosynthetic pathways are central metabolic pathways in both bio-fluids and could be analyzed further, either for the discovery of therapeutics or biomarker development. Overall, our study suggests that urine and plasma metabolomics may contribute to the identification of a distinct metabolic fingerprint of EAE disease discriminating from the healthy control which may aid in the development of an objective non-invasive monitoring method for progressive autoimmune diseases like MS.

Untargeted urinary metabolomics of a chronic mouse model of multiple sclerosis identified Phenylalanine, tyrosine & tryptophan metabolism as the significantly altered metabolic pathway. Eight common metabolites were identified when we combined urinary and plasma metabolic signature, which revealed a perturbation of Phenylalanine metabolism and valine, leucine & isoleucine metabolic pathways, involved in CNS dysfunction during diseases. The identified eight metabolic signature of urine and plasma may be of clinical relevance as potential biomarkers and guide towards the identification of specific metabolic pathways as novel drug targets.

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