5,933 research outputs found

    R&D, Foreign Technology and Technical Efficiency in Developing Countries

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    This study investigates the relationship between firms’ innovation activities and efficiency in manufacturing firms in developing countries. We examine whether innovation activities including internal research and development (R&D) and adoption of foreign technology have differential effects on technical efficiency. We hypothesize that the relation between internal R&D and technical efficiency is positive; the relation between adoption of foreign technology and technical efficiency is negative and lastly, internal R&D in combination with the adoption of foreign technology have a positive effect on technical efficiency. We use cross-sectional firm level survey data from the 2013 World Bank Enterprise Survey and the linked 2014 Innovation Follow-up Survey for examining the effect of innovation activities on firms’ technical efficiency. We test our hypothesis using cross-sectional stochastic frontier analysis. We find that internal R&D has a negative and significant effect on technical efficiency. Adoption of foreign technology on the other hand does not have a significant effect on technical efficiency. Nevertheless, the combination of internal R&D and adoption of foreign technology has a negative and significant effect on technical efficiency. We conclude that internal R&D may have dynamic effects on technical efficiency. Furthermore, efficiency may be observed in firms conducting internal R&D but results in relative inefficiency for firms not conducting R&D giving rise to overall inefficiency in the manufacturing industry. Lastly, low rates of human capital hamper R&D activity and the adoption of foreign technology in manufacturing firms in developing countries

    Institutions, Resources and Innovation in Developng Countries:A Firm Level Approach

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    This study examines how firm-level resources interact with regional institutional quality to explain innovation in developing countries. We hypothesize that the institutional environment within which the firm operates moderates the effect of firm-level resources on innovative output. We examine the moderating role of institutions with regards to the transformation of firm-level resources including internal research and development, employee level of education and quality certification into innovative output using firm-level data from the World Bank Enterprise Survey and the Innovation Follow-up Survey that includes the innovation module for the years 2010 through 2012. We test our hypotheses using a multilevel logistic model. We find that the effects of firm-level resources vary depending on the institutional environment and that regional institutional quality positively moderates the effects of the firm-level resources. The positive effects of internal research and development on innovative output are substantially reinforced by regional institutional quality

    Treatment of gastrointestinal hemorrhage

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    Background: We assessed the value of selective arteriography in the diagnosis and management of acute gastrointestinal hemorrhage. Methods: We reviewed the records of 107 consecutive patients who had gastrointestinal hemorrhage and underwent selective arteriography between January 1992 and October 2003: 10 had upper gastrointestinal bleeding, 79 had lower gastrointestinal bleeding, and 18 had varicose bleeding with portal hypertension. Selective embolization was attempted in 15 patients to obtain hemostasis. Angiographic findings were reviewed and prospective reports were compared with the final diagnosis and outcome. Results: Of 129 angiographic studies, 36 correctly revealed the bleeding site and 93 were negative. Extravasation was seen in 24 cases at the level of stomach (n = 2), duodenum (n = 1), small bowel (n = 5), or colon (n = 16). Indirect signs of bleeding sources were identified in 12 patients (stomach in one, small bowel in four, large bowel in four, liver in three). Transcatheter embolization induced definitive hemostasis in 11 of 15 patients (73%), namely in the stomach (n = 2), small bowel (n = 3), colon (n = 7), and liver (n = 3). Three patients required surgery after embolization. Conclusion: Abdominal arteriography may localize gastrointestinal bleeding sources in approximately one-third of cases. Selective embolization may provide definitive hemostasis in most instance

    Elevated levels of the angiogenic cytokines basic fibroblast growth factor and vascular endothelial growth factor in sera of cancer patients.

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    The concentration of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) was determined in the serum of 90 untreated and 42 treated metastatic cancer patients, including patients with colorectal, breast, ovarian and renal carcinomas, with an enzyme-linked immunosorbent assay (ELISA). Levels higher than the 95th percentile of the concentrations of a control group, i.e. 7.5 pg ml(-1) for bFGF and 500 pg ml(-1) for VEGF, were identified as 'elevated'. One measurement during follow-up was included into the analysis per patient. For 19 treated patients, consecutive serum samples were analysed. Fifty-seven per cent of all untreated patients had elevated serum levels of one or both angiogenic factors. The fraction of patients with elevated serum levels of bFGF and/or VEGF was similar in the different tumour types. Agreement of bFGF levels and VEGF levels, classified in relation to their respective cut-off values, was present in 67% of all patients. Fifty-eight per cent of the patients with progressive disease during treatment compared with 15% of the patients showing response to treatment (chi-squared test P < 0.05) had elevated bFGF and/or VEGF serum levels. When consecutive serum samples were analysed, two-thirds of the patients showing progressive disease had increasing serum levels of the angiogenic factors compared with less than one-tenth of the patients showing response (chi-squared test P < 0.05). The lack of association between the serum bFGF and VEGF levels and the tumour type may suggest an aspecific host reaction responsible for solid tumour-related angiogenesis. The main determinants of the serum bFGF and VEGF concentration are the progression kinetics of the metastatic carcinomas

    Microvessel quantification in primary colorectal carcinoma: an immunohistochemical study.

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    The vascularisation of human primary colorectal carcinomas was studied immunohistochemically using the endothelial cell markers CD31 and factor VIII-related antigen. Tumour sections were systematically scanned at a magnification of x 100 to find areas of intense neovascularisation. Microvessel counts within these vascular 'hotspots' were performed at magnification x 250. Regions in which tumour cords were surrounded by a collagen IV-positive basement membrane were compared with those in which this was absent and with normal mucosa. CD31 appeared to be a more sensitive marker for endothelial cells than factor VIII-related antigen (mean 185 +/- 59 and 120 +/- 38 microvessels mm-2). Within individual tumour sections microvessel counts in vascular hotspots with highest vessel density correlated significantly with microvessel counts in vascular hotspots with second highest vessel density (P < 0.01). Microvessel counts in tumour areas where collagen IV-positive basement membrane were absent exceeded those in areas where it was present (factor of 1.7) and those in normal mucosa (factor of 1.6). The differences in vessel density between individual tumours and the low variability in vessel density within individual tumours using this quantification technique allow us to investigate the prognostic value of vessel density in areas of intense neovascularisation in human primary colorectal carcinomas
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