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The synthesis of certain S-benzylisothiocarbamides and the assessment of their extreme pressure (ep) properties are reported. These additives were compared with a commercial additive. The tribological end effects were studied using a scanning electron microscope. m-chlorophenyl and p-tolyl-S-benzylisothiocarbamides were found to be potentially effective. The mechanism of ep activity is discussed and a theory put forward to explain the ep additive-metal interaction.  相似文献   
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The long term sequelae of childhood sexual abuse include many symptoms commonly encountered in general practice settings. Guidelines to empathic history taking, comprehensive assessment, and an overview of management are presented, together with a contextual background.  相似文献   
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Grossglauser and Tse (2001) introduced a mobile random network model where each node moves independently on a unit disk according to a stationary uniform distribution and showed that a throughput of Theta(1) is achievable. El Gamal, Mammen, Prabhakar, and Shah (2004) showed that the delay associated with this throughput scales as Theta(nlogn), when each node moves according to an independent random walk. In a later work, Diggavi, Grossglauser, and Tse (2002) considered a random network on a sphere with a restricted mobility model, where each node moves along a randomly chosen great circle on the unit sphere. They showed that even with this one-dimensional restriction on mobility, constant throughput scaling is achievable. Thus, this particular mobility restriction does not affect the throughput scaling. This raises the question whether this mobility restriction affects the delay scaling. This correspondence studies the delay scaling at Theta(1) throughput for a random network with restricted mobility. First, a variant of the scheme presented by Diggavi, Grossglauser, and Tse (2002) is presented and it is shown to achieve Theta(1) throughput using different (and perhaps simpler) techniques. The exact order of delay scaling for this scheme is determined, somewhat surprisingly, to be of Theta(nlogn), which is the same as that without the mobility restriction. Thus, this particular mobility restriction does not affect either the maximal throughput scaling or the corresponding delay scaling of the network. This happens because under this 1-D restriction, each node is in the proximity of every other node in essentially the same manner as without this restriction  相似文献   
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Encouraged by its Building Research Institute, Denmark has been examining how low rise, high density development might offer a better answer to mass housing needs than blocks of flats. The economic, organisational and sociological arguments which have arisen as a result are reviewed in this article.  相似文献   
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A plot of absorbance vs 1/time (the "1/time domain") is a more useful representation of the primary data in capillary electrophoresis than traditional plots of absorbance vs time (the "time domain") in a wide set of circumstances, especially when comparing electropherograms in which the rate of electroosmotic flow is not precisely the same. The quantity that is of fundamental interest in capillary electrophoresis (CE) is the electrophoretic mobility of an analyte. The electrophoretic mobility of a species is nonlinearly proportional to time and, therefore, not linearly represented in the time domain: that is, the distance between two peaks along the time axis is not linearly related to the difference in their electrophoretic mobilities. In contrast, the electrophoretic mobility is linearly proportional to 1/time, and the distance between two peaks along the 1/time axis is linearly related to the difference in electrophoretic mobilities. Plots in the 1/time domain are similar to the familiar plots in the time domain (each analyte is represented by a peak, and the order of peaks corresponds to the order in which these analytes reach the detector), but the spacing between the peaks corresponds linearly to differences in mobility. This article derives this useful, visually appealing, and broadly applicable plotting strategy and illustrates common situations in which these plots are more useful than plots in the time domain.  相似文献   
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BACKGROUND: The rarity of pancreatic tumours other than nesidioblastosis in children is such that the experience of any one surgeon or institution is small. As a consequence, there is limited information on the appropriate management and outcome of these tumours. For this reason a review was conducted of the experience of a large paediatric surgical institution. METHODS: During a 23-year period, six patients with pancreatic tumours other than nesidioblastosis were treated at the Royal Children's Hospital, Melbourne. RESULTS: Despite the varied modes of presentation and surgery undertaken, all six patients with surgery alone, with follow-up from 1 to 18 years. Two of the tumours were malignant; the remaining four being islet cell adenomata. No form of adjuvant treatment (chemotherapy or radiotherapy) was used. CONCLUSION: These rare paediatric tumours appear to have a good prognosis, even when malignant, and respond well to radical surgical ablation. Adjuvant therapy appears to be unnecessary.  相似文献   
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OBJECTIVE: To determine the effects of elevated endogenous E2 levels on in vitro platelet function in patients undergoing controlled ovarian hyperstimulation (COH). DESIGN: Women with normal ovulatory cycles and patients undergoing COH on cycle day 3 and near ovulation (preovulatory follicles were at least 16 mm in diameter) were studied. Serum E2, Thrombostat 4000, (V. d. Goltz, Seeon, Germany), von Willebrand factor antigen (vWF-Ag), and platelet aggregation and adenosine triphosphate (ATP) release to adenosine diphosphate (ADP), collagen (COL), and arachidonic acid (AA) were measured. SETTING: University-based outpatient infertility clinic. PATIENT(S): Twenty-two consenting infertile women undergoing COH cycles and 14 women with documented ovulatory cycles. MAIN OUTCOME MEASURE(S): Whole blood platelet aggregation with ADP, COL, AA, and Thrombostat 4000. RESULTS(S): Estradiol levels rose significantly at peak times (P = 0.011). No changes were noted in in vitro platelet function measured by the Thrombostat 4000 and by whole blood platelet aggregation with ADP and AA and in ATP release with ADP, COL, or AA. Aggregation with collagen was increased because of likely elevations in vWF-Ag levels. CONCLUSION(S): No significant changes in in vitro platelet function were noted in 19 women undergoing COH with E2 levels two to three times that observed in oral contraceptive or hormone replacement therapy users, suggesting no increased risk for arterial thromboembolism.  相似文献   
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Nutritional support is an important aspect of the management of burn patients. Nutrition supplementation can be achieved either by 'hospital-made' or 'commercial' diets. Commercial diets are efficacious but expensive and sometimes not easily available. This study was undertaken to compare the efficacy and tolerance of a hospital-made diet with a commercial diet. Twenty patients with burns ranging from 20-50 per cent TBSA were studied to compare the efficacy and tolerance of the 'hospital-made' diet with 'commercial' preparations. Patients were divided into two groups of 10 each and randomised within each group to receive either a hospital-made diet (five patients) or a commercial diet (five patients). Efficacy of diet was assessed by evaluation of nutritional status, graft take, number of surgical procedures and duration of hospital stay. Tolerance was assessed by recording side effects such as nausea, vomiting, abdominal distention and diarrhoea. Both diets were well tolerated by all patients. There was no significant difference in nutritional status, number of surgical procedures, percentage of graft take and duration of hospital stay on either diet, suggesting that hospital-made diets are similar in efficacy and tolerance but cheaper and more easily available. They are a good alternative to 'commercial' diets, especially in poor patients.  相似文献   
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