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31.
K.-W. Jauch 《Der Chirurg》1997,68(6):551-558
Summary. Trauma, operative interventions, infection and other disturbances of homeostasis lead to a uniform reaction of the body,
namely release and activation of hormones and cytokines. Profound alterations of substrate flow result, with mobilization
of energy stores and degradation of structural and functional proteins of vital organs like the gut mucosa. Due to these reactions
the energy demands of the organs are met and energy-consuming synthesis of substrates is indicated. Clinically, hypermetabolism,
hyperglycemia, lipolysis and increased urea production with negative nitrogen balance can be observed. The metabolic reactivity
is reached by an increased substrate cycling. To avoid negative consequences such as organ dysfunction, a rational situation-adapted
substrate supply is warranted as well as reduction of catabolic stimuli and stimulation of anabolic factors. The metabolic
care of the surgical patient is still a basic and important task.
相似文献
32.
四种可溶性载体对骨形态发生蛋白在小鼠体内诱导成骨活性的影响 总被引:28,自引:0,他引:28
以四种可溶性物质作为牛骨形态发生蛋白(bBMP)的载体,通过实验观察哪种物质是bBMP的有效缓释载体。将聚乙烯吡咯烷酮(PVP)、葡聚糖、羟乙基淀粉(HES)、甘露醇分别与等量bBMP复合后,注射入小鼠股部肌肉,观察组织学成骨及测定标本内钙含量。结果,bBMP/PVP有良好成骨,吸收较快,未见炎症及排斥反应,其混悬液较稳定,具有良好的适针性及可注射性,bBMP/甘露醇只有很低成骨率。其余各组未见成骨。PVP对bBMP具有满意助溶、助悬及缓释载体作用,对bBMP活性无损害,生物相容性好。 相似文献
33.
采用静态蒸汽总压法实验装置,在29.94℃、39.92℃和49.93℃下,测定了1,1,1,2-四氟乙烷-1,1-二氟乙烷二元系汽液相平衡时的物料,总量、系统组成、蒸汽总压和汽相体积。结合物料衡算和T、P、x推算y的曲面样条函数法,计算出对应的平衡汽液相组成。用改进的PR状态方程和一个与温度无关的可调相互作用参数关联了实验数据。 相似文献
34.
The purpose of this study was to evaluate whether the baseline stress-shortening data reflect the contractile state adequately and give results comparable to the evaluation of the end-systolic stress-shortening relationships using pharmacological manipulation of afterload. Five groups were studied (total 152 patients): a control group of 30 healthy volunteers, 32 patients after surgical correction of infantile tetralogy of Fallot, 50 patients treated for childhood malignancies with doxorubicin, 17 patients with left ventricular hypertrophy due to systemic hypertension, and 23 patients with congestive cardiomyopathy. In all patients except those with congestive cardiomyopathy, afterload was altered pharmacologically to evaluate the individual stress-shortening relationship. In all patients the baseline stress-shortening data were evaluated, as well as their relative positions to two predefined normal ranges for the relationship between end-systolic stress and shortening. Additionally, a slope value was calculated from the baseline data of the five groups studied and compared with the data obtained by pharmacological afterload increment. Our data show that the comparison of individual baseline data of end-systolic wall stress and fractional shortening with predefined normal ranges for the relationship between end-systolic stress and shortening is inadequate. The appropriate normal range to compare with is the 95% confidence interval of baseline stress-shortening data in normal subjects. Also the calculation of a slope value from the baseline stress-shortening data of a group of patients seems to be inappropriate. Such a slope value does not necessarily reflect the contractile state, as the specific conditions leading to variations of end-systolic wall stress are undefined and not standardized, and the correlation between baseline stress-shortening data depends largely on the influence of the end-systolic dimension on both parameters. 相似文献
35.
M Ochsner 《European journal of medicinal chemistry》1996,31(12):939-950
Zinc(II) phthalocyanine is the active component of the liposomal formulation CGP 55847 which showed a high activity in photodynamic therapy in a variety of animal tumours. The photophysical properties of zinc(II) phthalocyanine have been studied in detail and compared to those of Photofrin, the only sensitizing agent approved so far for phase III/IV clinical trials. Since the efficacy of photodynamic therapy intrinsically depends on the spectroscopic features of the sensitizer, quantum chemical methods have proven to be an efficient means for optimizing chemical structures. As will be shown, a simple modification of the time-honoured INDO model of Pople allows a prediction of the singlet and triplet state properties of molecules of the size of zinc(II) phthalocyanine with an rms error of ≤ 1000 cm−1. 相似文献
36.
The aim of the project was to survey the hospital prevalence of apallic syndrome in a federal state in Austria at an exact point in time. To achieve this, a point prevalence study was carried out on 28 November 2001 in the Vienna region. The central element was a questionnaire, which provided an exact recording of the patients' condition. An additional preliminary task was to check all the discharge diagnoses in the hospitals of the Vienna Hospital Association (Wiener Krankenanstalten Verbund) between 1996 and 2000 according to the ICD-9 diagnoses for apallic syndrome. These data should serve to cross-check the recorded results. All hospitals (n = 48) and nursing facilities (n = 44) in Vienna were included in this investigation. As the aim of the study was to record the prevalence of apallic syndrome in the population of Vienna, four patients of the group with full-stage apallic syndrome (n = 36) were excluded as they were from other federal states. In total, 32 hospital patients who met the clinical criteria for apallic syndrome (full-stage) were recorded. The point prevalence of apallic syndrome was 1.9/100,000 inhabitants. As a result of this study, the exact survey of hospital prevalence of apallic syndrome could be found. As a consequence, the Viennese government has developed a rehabilitation concept for patients with apallic syndrome in Vienna. 相似文献
37.
Rosina Stefanello 《Stress and health》2004,20(5):293-299
The aim of this work was to examine the occurrence of stressful events in the lives of children, using the ‘Scale of Infantile Social Readjustment’ (SISR), and the ‘Inventory of Symptoms of Infantile Stress’ (ISIS) to identify the presence of stress symptoms. The results of these evaluations were then used to examine the relationship between the levels of stress and the nutritional state of the children, by correlation. Forty 7–10‐year‐old children were included in the evaluation. From the analysed sample 49 per cent of them were eutrophic (weight/height normal to age), 50 per cent were above weight and 1 per cent was undernourished. Whereas 70 per cent of the girls were eutrophic and 30 per cent were above weight, only 35 per cent of the boys were eutrophic, 60 per cent were above weight and 5 per cent were undernourished. The results obtained in this first study indicated that 45 per cent of eutrophic girls demonstrated symptoms of stress, while 20 per cent of them were asymptomatic (with no symptoms of stress). Of the overweight boys, 30 per cent of them showed symptoms of stress and 35 per cent did not. This study indicated a possible relationship between weight and the symptoms of stress. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
38.
Carl Ganter 《Magnetic resonance in medicine》2004,52(2):368-375
A previously developed eigenvector formalism is adapted to off-resonance in the transient response of quasiperiodic steady-state free precession (SSFP) sequences, including TrueFISP as a special case. The effective relaxation rates for essentially parallel and perpendicular deviations from the steady state are determined analytically in leading order perturbation theory. The latter are a known cause of oscillatory artifacts and therefore constitute the main target of a variety of preparation techniques. In addition, the former also play a dominating role in applications such as inversion recovery (IR) TrueFISP, which intentionally measure far away from the equilibrium. For both components, the approach toward equilibrium turns out to depend sensitively on field inhomogeneities, especially for smaller ratios of T2/T1. For the perpendicular deviations, the calculations show that--except very close to banding artifacts, where the steady-state signal is almost zero--field inhomogeneities additionally increase their effective relaxation rate almost as much as in the free induction decay (FID). The analytical results are tested against numerical simulation and MR measurements. 相似文献
39.
Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts. 相似文献
40.
Carl Ganter 《Magnetic resonance in medicine》2006,55(1):98-107
Spoiled gradient echo sequences can only reach a homogeneous steady state if sufficiently strong crusher gradients are used in combination with RF phase cycling (RF spoiling). However, the signal depends quite sensitively on the chosen phase increment ? and—lacking analytical solutions—numerical simulations must be used to study the transient and steady‐state magnetization. For the steady state an exact analytical solution is derived, which holds for arbitrary sequence and tissue parameters. Besides a considerably improved computation performance, the analytical approach enables a better understanding of the complicated dependence on ?. For short repetition times (TR) the regime of small ? turns out to be particularly interesting: It is shown that the typical ?c, where RF spoiling starts to become effective, is essentially inversely proportional to T2. This tissue dependence implies that contrasts can be considerably larger with partial spoiling (? ≈ ?c) than with conventional RF spoiling (? ? ?c). As an example, the uptake of contrast agents in tissues is investigated. For typical parameters a considerably improved contrast enhancement can be obtained, both theoretically and experimentally. Magn Reson Med, 2006. © 2005 Wiley‐Liss, Inc. 相似文献