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101.
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Lemierre syndrome used to be a complication of severe oropharyngeal infection with regional thrombophlebitis, septicaemia and septic metastatic infections caused by Fusobacterium necrophorum in the pre-antibiotic era. A case of septic arthritis of the hip caused by F. necrophorum as a complication of tonsillectomy is reported in a 9-year-old boy. Conclusion: Lemierre syndrome, usually seen after an oropharyngeal infection, can also complicate tonsillectomy.  相似文献   
103.
Fuel cells have great application potential as stationary power plants, as power sources in transportation, and as portable power generators for electronic devices. Most fuel cells currently being developed for use in vehicles and as portable power generators require hydrogen as a fuel. Chemical storage of hydrogen in liquid fuels is considered to be one of the most advantageous options for supplying hydrogen to the cell. In this case a fuel processor is needed to convert the liquid fuel into a hydrogen-rich stream. This paper presents a second-law analysis of an integrated fuel processor and fuel cell system. The following primary fuels are considered: methanol, ethanol, octane, ammonia, and methane. The maximum amount of electrical work and corresponding heat effects produced from these fuels are evaluated. An exergy analysis is performed for a methanol processor integrated with a proton exchange membrane fuel cell, for use as a portable power generator. The integrated FP–FC system, which can produce 100 W of electricity, is simulated with a computer model using the flow-sheeting program Aspen Plus. The influence of various operating conditions on the system efficiency is investigated, such as the methanol concentration in the feed, the temperature in the reformer and in the fuel cell, as well as the fuel cell efficiency. Finally, it is shown that the calculated overall exergetic efficiency of the FP–FC system is higher than that of typical combustion engines and rechargeable batteries.  相似文献   
104.
In the present set of studies, the authors examine the idea that self-sacrificial leadership motivates follower prosocial behavior, particularly among followers with a prevention focus. Drawing on the self-sacrificial leadership literature and regulatory focus theory, the authors provide results from 4 studies (1 laboratory and 3 field studies) that support the research hypothesis. Specifically, the relationship between self-sacrificial leadership and prosocial behavior (i.e., cooperation, organizational citizenship behavior) is stronger among followers who are high in prevention focus. Implications for the importance of taking a follower-centered approach to leadership are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Anticipating the rise in ‘suspect’ samples caused by the introduction of a more sensitive screening test for the presence of antibiotic residues in slaughter animals, an additional microbial post-screening method was developed. The test comprises four antibiotic group specific test plates, optimized for the analysis of kidney and has been validated according to 2002/657/EC using fortified kidney samples. For each test plate activity profiles are presented, enabling a considerate choice of one or more representative component for each test plate. This information can be used to minimize validation efforts for further implementation of the test in routine field laboratories.  相似文献   
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The density of neon has been determined at 298.15 K as a function of pressure from 80 MPa to 1 GPa. The precision of the measurements is 0.03%, while the estimated absolute accuracy is between 0.05 and 0.09%. The sound velocity has been measured between 98 and 298 K with intervals of 25 K and at pressures up to 1 GPa, with an accuracy generally better than 0.06%. The adiabatic compressibility and the ratio of the specific heats are calculated by combining pVT with velocity-of-sound data at 298 K. Several equations of state are fitted to the density data at 298.15 K.Paper presented at the Tenth Symposium on Thermophysical Properties, June 20–23, 1988, Gaithersburg, Maryland, U.S.A.  相似文献   
109.
PURPOSE: Although anismus has been considered to be the principal cause of anorectal outlet obstruction, it is doubtful whether contraction of the puborectalis muscle during straining is paradoxical. The present study was conducted to answer this question. METHODS: During the first part of the study, we retrospectively reviewed 121 patients with constipation and/or obstructed defecation (male:female, 10/111; median age, 51 years). All of these patients underwent electromyography (EMG) of the pelvic floor and the balloon expulsion test (BET) in the left lateral position. Evacuation proctography was performed in all of these patients in the sitting position. Both the posterior anorectal angle and the central anorectal angle were measured. EMG and BET were also performed in ten controls (male:female, 4/6; median age, 47). In 147 patients with fecal incontinence (male:female, 24/123; median age, 58) only EMG activity was recorded. Criteria for anismus during straining were increase or insufficient (<20 percent) decrease of EMG activity, failure to expel an air-filled balloon on BET, and decrease or insufficient (<5 percent) increase of anorectal angle on evacuation proctography. Between June 1994 and March 1995, we conducted a second prospective study in a consecutive series of 49 patients with constipation and/or obstructed defecation and 28 patients with fecal incontinence. Both groups were compared with 19 control subjects. In this study, all three tests were performed. EMG and BET were performed both in the left lateral position and in the sitting position. RESULTS: The retrospective study was undertaken by comparing the constipated patients with the incontinent patients and the controls, and the anismus detected by EMG was found in, respectively, 60, 46, and 60 percent. Failure to expel the air-filled balloon was observed in 80 constipated patients (66 percent) and in 9 control subjects (90 percent). Based on posterior anorectal angle and central anorectal angle measurements, anismus was diagnosed in, respectively, 21 and 35 percent of constipated patients. In the prospective study, none of the tests showed significant differences regarding the prevalence of anismus between the two subgroups of patients and the control subjects. The prevalence of anismus only differed between constipated and incontinent patients when the diagnosis was based on BET in the sitting position (67 vs. 32 percent; P < 0.005). Our study shows that contraction of the puborectalis muscle during straining is not exclusively found in patients with constipation and/or obstructed defecation. The three tests most commonly used for the diagnosis of anismus showed an extremely poor agreement. CONCLUSION: Based on these findings, we doubt the clinical significance of anismus.  相似文献   
110.
The prognostic significance of steroid-receptor activity is still debatable. Discrepancies in results are probably attributable to few patients, heterogeneous patient populations, and short follow-up. We investigated the prognostic significance of estrogen- and progesterone-receptor (ER and PgR, respectively) activity as a continuous variable in a homogeneous patient population. The prognostic significance of steroid-receptor activity was examined in 329 node-negative and 320 node-positive unselected breast cancer patients. In node-negative patients, ER values of primary tumors between 100 and 400 fmol/mg protein appeared to be a significant predictor for low risk of recurrence, whereas high ER (> 400) revealed an unfavorable prognosis. The classic cutoff level of ER (< 10 fmol/mg proteins) had no prognostic significance, however. In patients receiving adjuvant chemotherapy--the node-positive breast cancer patients--the classic cutoff value of ER (10 fmol/mg protein) predicts significantly distant metastases-free survival and overall survival only in the first 4 years of follow-up after diagnosis. Progesterone receptor is a time-dependent prognosticator in node-negative breast cancer patients (cutoff point for PgR, 80 fmol/mg). In node-positive breast cancer patients treated with chemotherapy or a combination of chemo- and hormonal therapy, PgR values lower than 60 fmol/mg had a worse prognosis. The results show the poor performance of standard cutoff points for ER and PgR positivity in predicting prognosis. Better prognosis is related to higher receptor levels but this relation is predominantly time-dependent. Moreover, patients who have high ER levels have a prognosis that is worse when compared with intermediate ER levels. Standard cutoff points for steroid receptors should not be used to select patients for prognosis.  相似文献   
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