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1.
A novel experimental method was developed which allows the determination of the threshold concentration of sucrose by use of a linear sucrose gradient in water. With this method a continuous tasting of the test-liquid is possible. A panel of 15 persons experienced in taste-testing was used. Three gradients of different steepness were applied: 0 to 1.5% (w/w) sucrose in 2 min (I), 3 min (II) and 4 min (III). The results of the new method were compared with those of the standard method (DIN). With gradients I and II we found values which were significantly higher than those of the standard method (I: 0.49% (w/w); II: 0.46% (w/w); DIN: 0.31% (w/w)), whereas with gradient III the same threshold value was found as with the DIN-Method (III: 0.32% (w/w)).  相似文献   
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The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
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To bypass a diverse range of fork stalling impediments encountered during genome replication, cells possess a variety of DNA damage tolerance (DDT) mechanisms including translesion synthesis, template switching, and fork reversal. These pathways function to bypass obstacles and allow efficient DNA synthesis to be maintained. In addition, lagging strand obstacles can also be circumvented by downstream priming during Okazaki fragment generation, leaving gaps to be filled post-replication. Whether repriming occurs on the leading strand has been intensely debated over the past half-century. Early studies indicated that both DNA strands were synthesised discontinuously. Although later studies suggested that leading strand synthesis was continuous, leading to the preferred semi-discontinuous replication model. However, more recently it has been established that replicative primases can perform leading strand repriming in prokaryotes. An analogous fork restart mechanism has also been identified in most eukaryotes, which possess a specialist primase called PrimPol that conducts repriming downstream of stalling lesions and structures. PrimPol also plays a more general role in maintaining efficient fork progression. Here, we review and discuss the historical evidence and recent discoveries that substantiate repriming as an intrinsic replication restart pathway for maintaining efficient genome duplication across all domains of life.  相似文献   
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We have designed a flexible ecological momentary assessment/intervention smartphone (EMA/EMI) “app”. We examine the utility of this app for collecting real-time data, and assessing intra-subject variability, by using it to assess how freshman undergraduates spend their time. We also explore whether its use can promote greater self-awareness. Participants were randomly divided into an experimental group, who used the app, and a control group, who did not. We used the app to collect both randomized in-the-moment data as well as end-of-day data to assess time use. Using a posttest survey we asked participants questions about how they spent time throughout the school semester. We also asked the experimental group about their experience with the app. Among other findings, 80.49% participants indicated that they became more aware of how they spent their time using the app. Corroborating this report, among the experimental group, end-of-semester self-assessment of time spent wasted, and time spent using electronics recreationally, predicted semester GPA at a strength comparable to high school GPA and ACT score (two of the best single predictors for first semester college GPA), but had no correlation among controls. We discuss the advantages and limitations of using apps, such as ours, for EMA and/or EMI.  相似文献   
5.
The compulsory dispute settlement regime included in the 1982 Law of the Sea Convention is recognized as one of the most comprehensive in a modern international convention. Yet, in the recent application of this regime, the question has arisen as to whether the procedural prerequisites associated with the LOS Convention's compulsory dispute settlement mechanism are so arduous as to avoid binding and compulsory jurisdiction in most instances. This article addresses that question by examining, in particular, the reasoning of the Southern Bluefin Tuna arbitration tribunal, which found Article 281 of Section 1 of the LOS Convention to bar jurisdiction to the compulsory dispute settlement mechanism prescribed by the Convention, and offers suggestions as to how states might distinguish or overcome the barriers imposed by the Southern Bluefin Tuna tribunal in future cases.  相似文献   
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A new implantable electrocatalytic glucose sensor for subcutaneous glucose monitoring has been fabricated by immobilizing glucose oxidase on a chemically modified carbon fiber. The sensor was inserted subcutaneously on a male spraguely rat without any incision after dipping the microsensor in the rat's serum for 3 days. The so called "stained" microsensor, operated in the amperometric mode with an applied potential of +0.23 V versus Ag|AgCl, was able to directly measure the glucose concentration upon infusion of glucose. The results obtained were encouraging, with the response time was less than 2s and the apparent Michaelis-Menten value at 5.1+/-0.5mM. The "stained" microsensor shows good stability and reproducibility with constant response spanned over 25 days. Most common interferences in glucose analysis were minimized by the outerlayer Nafion. Hematology examinations showed minimal material-tissue interaction. Use of such mechanical devices will allow a more refined understanding towards glucose control in diabetic patients as the implanted microsensor was not effected by biocompatibility failures.  相似文献   
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The enzyme methionine aminopeptidase-2 (MetAP-2) is thought to play an important function in human endothelial cell proliferation, and as such provides a valuable target in both inflammation and cancer. Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with increased synovial vascularity, and hence is a potential therapeutic target for angiogenesis inhibitors. We examined the use of PPI-2458, a selective non-reversible inhibitor of MetAP-2, in disease models of RA, namely acute and chronic collagen-induced arthritis (CIA) in mice. Whilst acute CIA is a monophasic disease, CIA induced with murine collagen type II manifests as a chronic relapsing arthritis and mimics more closely the disease course of RA. Our study showed PPI-2458 was able to reduce clinical signs of arthritis in both acute and chronic CIA models. This reduction in arthritis was paralleled by decreased joint inflammation and destruction. Detailed mechanism of action studies demonstrated that PPI-2458 inhibited human endothelial cell proliferation and angiogenesis in vitro, without affecting production of inflammatory cytokines. Furthermore, we also investigated release of inflammatory cytokines and chemokines from human RA synovial cell cultures, and observed no effect of PPI-2458 on spontaneous expression of cytokines and chemokines, or indeed on the angiogenic molecule vascular endothelial growth factor (VEGF). These results highlight MetAP-2 as a good candidate for therapeutic intervention in RA.  相似文献   
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