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991.
H G Beger R Bittner E Sch?lzel M Büchler S Block P Malfertheiner 《Chirurgie; mémoires de l'Académie de chirurgie》1989,115(3):193-201
In 122 patients with severe chronic pancreatitis and inflammatory enlargement of the head of the pancreas a duodenum-preserving resection of the pancreatic head was performed. Postoperative hospitalization was 16 days in median, the frequency of re-operation was 4.9%. In the early postoperative phase one patient died and hospital mortality amounted to 0.8%. Following a medium follow-up period of 4.2 years (min. 6 months, max. 15 years) 7 patients died (late mortality 4.9%). 77% of the patients were completely free of abdominal pain, 84% went back to their previous occupation. During the follow-up period in 81% of the patients the glucose metabolism was unchanged, in 13% it deteriorated, and in 5% it improved permanently; 80% of the patients had a marked increase in weight averaging 8.7 kg. Compared to the Whipple procedure the duodenum-preserving resection of the head of the pancreas spares the patient with chronic pancreatitis a gastric resection, the duodenectomy, and the resection of the extrahepatic bile ducts. The limited operative intervention at the head of the pancreas in terms of a subtotal resection and the preservation of the duodenum explains the low early and late postoperative morbidity and mortality. 相似文献
992.
OBJECTIVE: Right ventricular (RV) dysfunction remains the leading cause of early mortality after cardiac transplantation. The effect of brain death and subsequent hypothermic cardioplegic arrest and storage on subsequent post-transplant right ventricular function was examined. SUMMARY BACKGROUND DATA: Right ventricular dysfunction in the donor heart usually is attributed to failure of the donor right ventricle to adapt to the sudden increase in afterload (pulmonary vascular resistance) in the recipient. Strategies to improve ventricular mechanics in the postoperative period are aimed at reducing pulmonary vascular resistance with vasodilators or augmenting right ventricular contractility with inotropic agents. Events occurring in the donor heart (brain death, hypothermic cardioplegic arrest, and storage) also may be directly related to post-transplant RV dysfunction. METHODS: A canine model of brain death and orthotopic cardiac transplantation was used. A dynamic pressure-volume analysis of RV mechanics was performed using micromanometers and sonomicrometric dimension transducers. Systolic function was assessed by measurement of preload recruitable stroke work (PRSW). Brain death was induced in 17 dogs by inflation of an intracranial balloon. Right ventricular function then was assessed serially to 6 hours (PRSW). Right ventricular adrenergic beta receptor density and function was sampled at control and after 6 hours of brain death. The effect of cardioplegic arrest and hypothermic storage was assessed in a second group of 17 dogs, using the same instrumentation and method of RV analysis. RESULTS: A significant decrease in right ventricular PRSW occurred after brain death, with the average decrease being 37% +/- 10.4% from the control. The RV myocardial beta adrenergic receptor density did not significantly change (253 +/- 34 fmol/ng control vs. 336 +/- 54 fmol/ng after brain death). The adenylyl cyclase activity of the RV beta receptor was assessed and was not altered by brain death. Orthotopic transplantation after cardioplegic arrest and hypothermic storage significantly decreased RV PRSW from 23.6 +/- 2.0 x 10(3) erg to 13.5 +/- 1.4 x 10(3) erg. CONCLUSIONS: These data indicate that the donor right ventricle is exposed to factors significantly detrimental to its mechanical performance well before facing an increased afterload in the recipient. Strategies to reduce RV dysfunction associated with brain death and hypothermic storage could positively impact post-transplant survival. 相似文献
993.
Stefan Herzig Julia Jischa Antje Beinhauer Bettina Geirhos Kristin Tacke Ralf G. Hempelmann 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(6):636-643
The functional interaction between the dihydropyridine calcium channel blocker nitrendipine and quinidine was studied in isolated preparations from guinea-pig cardiac ventricle and in mesenteric arterial segments under a variety of experimental conditions. The negative inotropic potency of nitrendipine is clearly enhanced by quinidine (3·10–6-10–4 mol/l) by up to two orders of magnitude, i.e. cardiac nitrendipine effects are potentiated. Vasorelaxant effects, however, remain largely unaffected (nitrendipine potency is increased by half an order of magnitude maximally).To elucidate the mechanism of this interaction, the ability of quinidine to potentiate the negative inotropic effect of a series of 12 dihydropyridines was compared with their voltage-dependence of action in guinea-pig left atria. No significant correlation is found (r = 0.18). Furthermore, quinidine inhibits rather than stimulates binding of tritiated nitrendipine, nimodipine or (S)-isradipine to isolated cardiac membranes. Therefore, the mechanism of the quinidine-nitrendipine interaction differs from those previously proposed for modulation of dihydropyridine binding by other drugs.We hypothesize that quinidine-occupied calcium channels adopt an intermediate affinity for nitrendipine, higher than in resting channels, but lower than the high affinity present with inactivated channels. Model calculations which are based on this assumption are able to reproduce all experimental findings of this study. 相似文献
994.
S Wiersbitzky T F Schwarz R Bruns G J?ger S Bittner H Weidemann F Deinhardt B Hottentr?ger E Abel L Ladst?tter 《Kinder?rztliche Praxis》1990,58(4):185-189
We tested 638 human sera of all age groups (patients and blood donors) from the northern area of the G.D.R. and found 216 cases (33.9%) of specific parvovirus B19 antibodies (IgG) by antibody capture ELISA. The seroprevalence rose to 36.7% when the 18 parvo B19-IgM- and/or parvo B19-DNA-positive results were included. The antibody prevalence was 24.9 (27.8% resp.) in the 0-10 years group and increased continuously in the following age groups up to 61.1% (69.4% resp.) in the 51-60 years group. 50% of the newborn infants showed parvo B19-IgG-antibodies in the cord blood (of maternal origin). No sex differences in seroprevalence were observed. Parvovirus B19 is obviously very prevalent in the G.D.R. population. The main immunization occurs in the first 30-40 years of life but infection with parvo B19 at a later age is also well documented. Hence it follows that 35-45% of all G.D.R. females of reproductive age are susceptible to a parvovirus B19 infection. 相似文献
995.
Clinical presentation of a child with port-wine stain and seizures leads to the suspicion of Sturge-Weber disease (SWD). This diagnosis can be confirmed by the detection of a meningeal angiomatosis. In rare cases, early detection of meningeal pathology by ultrasound has been reported. Key findings are brain atrophy, gyriform cortical calcifications demonstrated by skull radiographs after the first year of life or earlier by cranial CT, and dys- or aplasia of the deep cerebral veins on angiography. Radionuclide imaging shows focal or diffuse tracer accumulation over the affected brain regions. MR demonstrates an abnormal appearance of the affected meninges, especially thickening and pathologically increased signal intensity after Gd-DTPA application. This, in association with the demonstration of abnormal enhancement in deep medullary veins, is the most characteristic finding. Contrast-enhanced MR allows early and non-invasive diagnosis of SWD, mainly by revealing leptomeningeal angiomatosis and abnormal venous vessels. 相似文献
996.
997.
Angus Craig Kerstin Baer Antje Diekmann 《International archives of occupational and environmental health》1981,49(2):105-114
Summary Forty students performed on a perceptual discrimination task both before and after a mid-day lunch interval. Half of the students
consumed a three-course lunch during the interval, the remaining half abstained from lunch. It was found that the actual ability
to discriminate between events was significantly impaired following the consumption of lunch, but did not alter when no food
was ingested. The magnitude of the post-lunch dip in discrimination efficiency was significantly greater in the less “neurotic”
and the more “extraverted” individuals, according to scores on the Eysenck Personality Inventory, and was also significantly
though negatively related to the extent of the drop in sublingual temperature that occurred over the lunch interval. It is
concluded that operational efficiency and safety may be at risk following lunch. 相似文献
998.
999.
Bilaterally increased VEGF-levels in muscles during experimental unilateral callus distraction. 总被引:6,自引:0,他引:6
Nils Hansen‐Algenstaedt Petra Algenstaedt Antje Bttcher Claudia Joscheck Britta Schwarzloh Christian Schaefer Ingo Müller Chieko Koike Wolfgang Rüther Bernd Fink 《Journal of orthopaedic research》2003,21(5):805-812
Angiogenesis is essential for wound healing and proliferative processes such as bone formation and repair. Since increased expression of the vascular endothelial growth factor (VEGF) stimulates bone formation, it can be hypothesized that surgical procedures leading to a systemic increase of VEGF for instance during wound healing, influence enchondral ossification processes and might be responsible for observed growth phenomena during callus distraction. To study the mechanisms of angiogenesis in soft tissue during unilateral callus distraction, lengthening of the right tibia was performed in 12 beagles. After osteotomy, application of a ring fixator and after five latency days, distraction was started for 25 days. A control group of four additional beagles underwent no surgical procedure. Subsequent to the distraction period (Group A), muscle samples from six beagles were taken from the distracted side (ds) and the contralateral non-distracted side (n-ds), six beagles underwent an additional consolidation period of 25 days (Group B). Samples were analyzed for VEGF, VEGFR-1 and VEGFR-2 mRNA expression using real-time PCR and protein expression using Western Blot analysis. Muscles from both extremities showed significantly increased expression of VEGF and its cognate receptors VEGFR-1/2. Expression decreased significantly after the consolidation period, whereby the level at the non-distracted side decreased more than the level at the distracted side. Interestingly VEGF and VEGFR-1 levels at the non-distracted side were significantly higher than at the distracted side. In contrast VEGFR-2, the receptor that mediates endothelial cell proliferation, showed higher levels at the distracted than at the non-distracted side. These findings indicate that callus distraction results not only in locally increased expression of VEGF and its receptors, but leads also to increased VEGF and VEGFR-1/2 levels at distant sides and might therefore be responsible for the observed growth phenomena during callus distraction. 相似文献
1000.
Computer simulations suggest that the simplest versions of the residual calcium model do not predict facilitation during trains of equal-interval stimuli at frog neuromuscular junctions or other synapses. Various modifications of the residual calcium model (e.g. continuous increase in number of active release sites or changes in calcium influx) could account for the observed data. 相似文献