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Research funding has been seen as one of the most important resource in the reward system of science. And usage of publications denotes an interesting perspective of user behavior in scientific communication. This study aims to address the relationship between funding and Usage Count, which is a new metrics item established on the platform of Web of Science. Full records of 300,010 articles published in 2013 were downloaded in October 2015, and divided into six disciplines, including information science library science, education educational research, economics, computer science, materials science, and chemistry. Seven indicators were proposed to measure the impact, including Funding rate, Citation per paper, Usage rate, Usage per paper, Citation difference, Usage difference, and Conversion rate. It concluded funding has impact on usage and citation, and funded papers attract more usage, but varying in different disciplines. Usage Count can be used in the extension of citation metrics but with limits. This study originally engages with usage metrics and detected that there is positive correlation between usage and funding.  相似文献   
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This article is focused on the phase structure development in immiscible polymer blends during melt mixing. Nonuniformity of the phase structure, i.e., the coexistence of areas containing particles with markedly different size distribution, was detected in quenched and compression molded samples of a number of various blends prepared by long and intensive mixing in the chamber of a Plasticorder. The same effect was found also for polystyrene/polyamide blends prepared in a twin‐screw extruder. It was shown that neglecting nonuniformity of the phase structure can lead to considerable error in evaluation of the effect of system parameters on the blend morphology. The reasons for the effect were discussed and it was found that inhomogeneous flow field in mixers is a plausible explanation of the nonuniform phase structure. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers  相似文献   
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We report a patient with a metastatic parathyroid carcinoma and medullary carcinoma of the thyroid. This patient represents a variation of the multiple endocrine neoplasia syndrome (MEN) type 2A. There was no evidence of a phaeochromocytoma. The case illustrates the difficulties that may be encountered in localising the source of PTH secretion; the patient underwent four unsuccessful exploratory operations of the neck and mediastinum before further investigations revealed a single metastatic deposit of parathyroid carcinoma involving the first thoracic vertebra. PCR amplification and sequencing of the RET oncogene from the metastatic parathyroid carcinoma and genomic DNA revealed a heterozygous mutation (Cys634Tyr) in exon 11, as has previously been described to occur in MEN 2A. In addition, loss of tumour heterozygosity was demonstrated at loci from chromosomes 1, 2, 3p, 13q and 16p. This represents the first report of a parathyroid carcinoma in a MEN2A patient, in which the multiple allelic deletions are consistent with the generalised losses observed in aggressive tumours.  相似文献   
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Cholesterol 7 alpha-hydroxylase, the rate-limiting enzyme in the bile acid biosynthetic pathway, is thought to be regulated by hydrophobic bile acids through negative feedback control. The role of cholesterol in the regulation of cholesterol 7 alpha-hydroxylase is more controversial, in part because of incomplete understanding of the relationship between the pathways of cholesterol synthesis and degradation. The main objective of this study was to define the interaction between these two pathways in an experimental model in which the supply of newly synthesized cholesterol was interrupted by sustained infusion of mevinolin (lovastatin), an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) or accelerated by a continuous infusion of mevalonate, a cholesterol precursor. The study was carried out in rats subjected to short-term bile fistula. In one set of experiments, rats were treated postoperatively with mevinolin (5 mg/kg loading dose followed by 2 mg/kg/hr infusion), mevalonate (180 mumol/hr infusion) or both for up to 96 hr. In a separate set of experiments, rats were infused intraduodenally with taurocholate (36 mumol/100 gm/hr for up to 96 hr). We determined cholesterol 7 alpha-hydroxylase- and HMG-CoA reductase specific activities at those time intervals, whereas bile acid synthesis rates were determined throughout the study. Compared with rats not subjected to surgery, rats with short-term biliary diversion had increases in cholesterol 7 alpha-hydroxylase activity of 259% and 827% at 48 and 96 hr, respectively. The increase in bile acid biosynthesis was less pronounced. Continuous infusion of mevinolin completely prevented increases in cholesterol 7 alpha-hydroxylase specific activity and bile acid biosynthesis at both time intervals.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BACKGROUND: Previous studies have documented greater use of health services by depressed persons and have postulated that health care costs could be reduced overall through better recognition and treatment of depression. OBJECTIVE: To determine whether a greater burden of medical illness contributes to excess charges for diagnostic tests among older adults with symptoms of depression. DESIGN: Prospective cohort study. SETTING: A primary care group practice at an academic institution. PATIENTS: 3767 patients 60 years of age and older who completed testing on the Centers for Epidemiologic Studies Depression Scale (CES-D) during routine office visits. MEASUREMENTS: Charges for all inpatient and ambulatory diagnostic testing for 2 years, including clinical pathology, diagnostic imaging, and special procedures; number of visits to the ambulatory care center or emergency department; and number of hospitalizations. The Ambulatory Care Group case-mix approach, which is based on ambulatory diagnoses, was used as a measure of health status and expected resource consumption. RESULTS: Patients with symptoms of depression (CES-D scores > or = 16) were significantly younger (66.6 compared with 68.1 years; P < 0.001), more likely to be white (50.5% compared with 33.9%; P = 0.001), and more likely to be female (75.8% compared with 67.6%; P = 0.001) than were those without these symptoms (CES-D scores < 16). They also had more nonpsychiatric comorbid conditions, had more visits to the ambulatory care center (9.2 compared with 7.8; P < 0.001), were more likely to use the emergency department (52.3% compared with 40%; P = 0.001), were more likely to be hospitalized (22.4% compared with 17%; P = 0.002), and had greater median total diagnostic test charges for a period of 1 year ($583 compared with $387; P < 0.001). The difference in charges, most of which were clinical pathology charges (54.2%), persisted into the second year. Ambulatory Care Group assignment was independently associated with diagnostic test charges. The CES-D summary score was not independently associated with diagnostic test charges when controlling for Ambulatory Care Group assignment. CONCLUSIONS: Patients with symptoms of depression accrue greater average diagnostic test charges. However, these data suggest that such patients also have a greater burden of comorbid nonpsychiatric illness. Efforts to improve outcome and decrease cost for patients who have late-life depression must target interventions to improve the care of psychiatric and medical illness concurrently.  相似文献   
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