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31.
Effectively managing and optimizing the value of the patent portfolio is a major challenge for many firms, especially those in knowledge intensive industries, such as the pharmaceutical, biotechnological and chemical industry. However, insights on effective patent portfolio strategies are rare. Therefore, in this article we investigate in detail how firms successfully manage and optimize their patent portfolios to increase their overall competitiveness. We discover that successful patent portfolio management is rooted in managing the patents along their life cycles. Based on the findings of ten case studies, we develop a holistic patent life cycle management model reflecting five distinctive phases of patent management: explore, generate, protect, optimize and decline. We conclude with how our findings can be used in practice.  相似文献   
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A one-day laboratory course on positron emission tomography (PET) for the education of physics students and PhD students in medical physics has been set up. In the course, the physical background and the principles of a PET scanner are introduced. Course attendees set the system in operation, calibrate it using a 22Na point source and reconstruct different source geometries filled with 18F. The PET scanner features an individual channel read-out of 96 lutetium oxyorthosilicate (LSO) scintillator crystals coupled to avalanche photodiodes (APD). The analog data of each APD are digitized by fast sampling analog to digital converters (SADC) and processed within field programmable gate arrays (FPGA) to extract amplitudes and time stamps. All SADCs are continuously sampling with a precise rate of 80 MHz, which is synchronous for the whole system. The data is transmitted via USB to a Linux PC, where further processing and the image reconstruction are performed. The course attendees get an insight into detector techniques, modern read-out electronics, data acquisition and PET image reconstruction. In addition, a short introduction to some common software applications used in particle and high energy physics is part of the course.  相似文献   
34.
Endogenous polyphenolic compounds in cacao impart both bitter and astringent characteristics to chocolate confections. While an increase in these compounds may be desirable from a health perspective, they are generally incongruent with consumer expectations. Traditionally, chocolate products undergo several processing steps (e.g., fermentation and roasting) that decrease polyphenol content, and thus bitterness. The objective of this study was to estimate group rejection thresholds for increased content of cocoa powder produced from under-fermented cocoa beans in a semisweet chocolate-type confection. The group rejection threshold was equivalent to 80.7% of the non-fat cocoa solids coming from the under-fermented cocoa powder. Contrary to expectations, there were no differences in rejection thresholds when participants were grouped based on their self-reported preference for milk or dark chocolate, indicating that these groups react similarly to an increase in high cocoa flavanol containing cocoa powder.  相似文献   
35.
Computers used as supporting tools for diagnostics, operation planning and therapy are of increasing relevance in surgery. Rapid progress in imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRT) and ultrasound already allows to represent anatomical and physiological conditions with maximal authenticity. In order to simulate complex surgeries we must develop ergonomic and intuitively useable software tools, thus enabling a precise and fast virtual execution of the planned surgical intervention preoperatively. Intraoperative support will consist of passive navigation tools, available already today, supporting the intraoperative orientation and, in the future, robots performing specific steps autonomously. Methods of augmented reality for the interaction of virtual objects and the real surgical scene are also suitable for the visualization of planning data and other medically relevant information in the operation situs. In maxillofacial and craniofacial surgery the techniques mentioned have been applied in all fields from dental implantology up to the correction of craniofacial malformations and the resection of skull base tumors. Many applications are still being developed or are still in the form of a prototype. However, it is already clear that developments in this area will have a considerable effect on a surgeon's routine work.  相似文献   
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Exogenous reinfection in experimental airborne tuberculosis   总被引:1,自引:0,他引:1  
This study of experimental airborne tuberculosis in which guinea pigs were infected with tubercle bacilli of low and high virulence, provides no support for hypotheses suggesting that a second or third exposure to tubercle bacilli leads to an adverse effect on host response to the first infecting strain or to the reinfecting strain. The principal influence of the first infection was to protect against a subsequent infection. This protection was most evident as inhibition of the spread of bacilli from the lungs to the spleen. The first infection appeared to exert less influence on events at the site of reimplantation of organisms in the lungs.  相似文献   
38.
Eighty-seven patients diagnosed as having primary Raynaud's phenomenon (Raynaud's disease) were reexamined after this symptom had been present for a mean of 8.8 years (range 2.0-34.5). One or more additional clinical feature(s) suggesting an underlying connective tissue disease were found in 12 patients (14%) at first evaluation, and in 23 (26%) by the last evaluation. The most frequent findings were puffy fingers (10 patients), digital tip pitting scars (8 patients), and digital tip ulcerations (6 patients). Distal esophageal hypomotility and/or decreased pulmonary diffusing capacity for carbon monoxide were found in 12 patients. Only 4 individuals (5%) developed clear evidence of a connective tissue disease, and in all cases, the diagnosis was the CREST (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasias) syndrome variant of systemic sclerosis. This condition became obvious 8-17 years after the onset of Raynaud's phenomenon. One or more serologic test values were initially abnormal in 2 of these CREST syndrome patients, as well as in 12 patients who continued to have primary Raynaud's phenomenon at the last evaluation. The combination of puffy fingers, digital pitting scars, and serum anticentromere antibody, all consistent with CREST syndrome, occurred in a small group of patients. None of the 78 patients whose serologic tests were repeated during followup had a change in the serologic profile. These results suggest that only a small proportion of patients with primary Raynaud's phenomenon develop one of the connective tissue diseases during the first decade after onset. When such a disorder does appear, systemic sclerosis with the CREST syndrome variant is the most likely eventual diagnosis.  相似文献   
39.
After ingestion of 12 g of theophylline caused severe toxicity in a young woman, we developed an experimental canine model to study human theophylline toxicity. Our study involved four anesthetized dogs given theophylline in a continuous intravenous drip for 180 minutes in one of four protocols. The protocols included a low-dose infusion (400 mg/h), a high-dose infusion (1000 mg/h), a high-dose infusion with beta-blockade induced by propranolol at 125 minutes after infusion, and a high-dose infusion while maintaining beta-blockade with propranolol throughout the experiment. Toxic levels of theophylline were associated with hypokalemia, hypophosphatemia, hyperglycemia, metabolic acidosis, and hypotension in both the patient and the experimental series. These effects were either prevented or partially reversed after induction of beta-blockade with propranolol. Very high levels of theophylline were associated with elevated levels of norepinephrine and epinephrine in the animals.  相似文献   
40.
In the current studies, we have explored agonist-mediated down-regulation of adrenergic receptors in vivo. We infused catecholamines from sc implanted osmotic minipumps and examined the effects of the resultant increases in circulating levels of catecholamines on rat renal cortical alpha- and beta-adrenergic receptor subtypes, as assessed in radioligand binding studies. Infusion of epinephrine or norepinephrine (at 150 micrograms/kg X h) elevated plasma levels of each catecholamine 10- to 20-fold and decreased renal cortical alpha 1-receptor number about 50% without changing alpha 2-receptor number. Isoproterenol infusion (150 micrograms/kg X h) raised plasma levels of this catecholamine, but had no effect on the number of either alpha 1- or alpha 2-receptors. Renal cortical beta-adrenergic receptor number was decreased by infusion of all three catecholamines. However, the beta 1- and beta 2-adrenergic receptors were altered selectively by the different agonists. Infusion of norepinephrine decreased both beta 1- and beta 2-receptor number, but was more effective for the beta 1-receptors; this result was somewhat at variance with that we previously reported for rats bearing transplanted pheochromocytomas. The decrease in beta-receptor number due to epinephrine infusion was largely due to loss of the renal cortical beta 2-receptors. Infusion of isoproterenol decreased the number of both beta 1- and beta 2-receptors (69% and 75%, respectively). Infusion of norepinephrine maximally decreased the number of alpha 1-, beta 1-, and beta 2-receptors within 2 days, and the t 1/2 for receptor loss was about 12 h. beta-Receptors lost in response to isoproterenol infusion could not be recovered in a pellet prepared by high speed centrifugation of the supernatant derived from the preparation of renal cortical membranes. These results indicate that adrenergic receptor subtypes are differentially down-regulated by elevated levels of circulating catecholamines and that this differential loss of receptors depends on the nature of the receptor subtype, the agonist, and perhaps also whether catecholamines are infused rather than increased by pheochromocytoma.  相似文献   
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