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101.
Zusammenfassung Während der sterilenAutolyse der weißen Hirnsubstanz bis zu 24 Tagen verändern sich die Lipoide nur geringfügig. Die erst vom 9. Tage an verstärkte Abnahme des Lipoid-P beruht auf der Spaltung von Lecithin und Plasmalogen und wird von einer entsprechenden Zunahme freier Fettsäuren (FFS), geringerer der Aldehyde begleitet. FFS sind in der frischen weißen Substanz nur in Spuren nachweisbar. Lysophosphatide treten—im Gegensatz zu anderen Organen—in papierchromatographisch nachweisbarer Menge nicht auf. Cholesterin und seine Ester bleiben unverändert. Kephaline, Inositphosphatide, Sphingomyelin, Cerebroside und Sulfatide verhalten sich chromatographisch weitgehend konstant. Die postmortale Autolyse hat bis mehrere Tage nach dem Tode keinen nennenswerten Einfluß auf die Lipoidzusammensetzung.Bei der Untersuchung von 20 verschiedenenErweichungsherden des Gehirns fand sich eine vom Alter der Herde nicht unbedingt abhängige Zunahme der FFS, Aldehyde, Triglyceride und Cholesterinester. Freie wie auch glycerid- und cholesteringebundene Fettsäuren und freie höhere Aldehyde stammen offensichtlich aus den strukturbildenden Lipoiden des Myelin. In verschiedenen Herden treten spurenweise Lysophosphatide auf.
Summary Lipides change slightly during sterile autolysis of human white matter up to the 24 th day. From the 9 th day on, there is a decrease of lipid-phosphorus caused by a breakdown of lecithin and plasmalogen accompanied by a comparable increase of free fatty acids (FFA) and aldehydes. In fresh white matter there are only traces of FFA. In the autolysing brain, contrary to several other autolysing organs, there are no lysophosphatides detectable by means of paper chromatography. Free and esterified cholesterol, cephalins, phosphoinositides, sphingomyelin, cerebrosides and sulfatides remain chromatographically constant during sterile autolysis. According to the above findings it can be concluded that postmortem autolysis up to several days duration has only neglectable effects on the lipid-composition of the white matter.After analysis of 20 different foci of anaemic softening of human brain we found an increase of FFA, aldehydes, triglycerides and of esterified cholesterol which is independent on the age of the lesion. FFA as well as those fatty acids which are bound to glycerol and cholesterol and free higher aldehydes derive from the myelin lipides. Also in contrast to autolysis there were traces of lysophosphatides found in several foci.


Herrn Prof. Dr.E. Letterer zum Geburtstag am 30. Juni 1966 gewidmet.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   
102.
103.
The European Laryngological Society is proposing a classification of different laryngeal endoscopic cordectomies in order to ensure better definitions of postoperative results. We chose to keep the word “cordectomy” even for partial resections because it is the term most often used in the surgical literature. The classification comprises eight types of cordectomies: a subepithelial cordectomy (type I), which is resection of the epithelium; a subligamental cordectomy (type II), which is a resection of the epithelium, Reinke’s space and vocal ligament; transmuscular cordectomy (type III), which proceeds through the vocalis muscle; total cordectomy (type IV); extended cordectomy, which encompasses the contralateral vocal fold and the anterior commissure (type Va); extended cordectomy, which includes the arytenoid (type Vb); extended cordectomy, which encompasses the subglottis (type Vc); and extended cordectomy, which includes the ventricle (type Vd). Indications for performing those cordectomies may vary from surgeon to surgeon. The operations are classified according to the surgical approach used and the degree of resection in order to facilitate use of the classification in daily practice. Each surgical procedure ensures that a specimen is available for histopathological examination. Received: 29 December 1998 / Accepted: 2 July 1999  相似文献   
104.
Mitotic gene conversions, among other recombinagenic events,can play an important role in the multistep process of carcinogenesis.The ability of chemicals to induce such gene conversions caneasily be monitored in the Saccharomyces cerevisiae tester strainYHE2, a derivative of strain D7. For the detection of drug-inducedgene conversions, two mutations in the TRP5 locus are used,trp5–12 and trp5–27. Here we report on the characterizationof the stable allele trp5–27. Our analysis revealed tworelevant mutations in trp5–27: (a) a transition C to Tat position 121 after ATG that results in an amber stop codonand abolishes gene expression and (b) a transversion A to Tat position 1555 that creates an ochre stop codon. Simultaneousamber and ochre suppression with the suppressors SUP3 and SUP11,respectively, was capable of relieving the tryptophan-requiringphenotype of strains carrying the trp5–27 allele. Thesefindings have implications on the length of gene conversiontracts in conversion events between trp5–12 and trp5–27:conversion tracts can cover several kilobases, if the site ofthe mutation in trp5–12 lies outside of the positionsmutated in trp5–27. Conversely, the maximal length islimited to 1435 bp, if the mutation in trp5–12 is locatedbetween the positions mutated in trp5–27. 1To whom correspondence should be addressed  相似文献   
105.
Summary This publication describes a new model to investigate the influence of tumor necrosis factor- (TNF-) on a three-dimensional glial cell aggregate under defined, standardized, reproducible conditions using the glioma cell line A 172.The cells are initially grown as normal monolayer culture until they reach a cell density of up to 1×106. Subsequently they are grown as spheroids by the liquid overlay technique. Spheroids grown in this way were divided into ten groups of more than 50 cell aggregates. Three groups were coincubated with free TNF- in increasing dosages (100 ng/ml, 200 ng/ml and 1000 ng/ml); three groups were incubated with empty liposomes (0.2 mg/ml, 0.4 mg/ml and 2 mg/ml); three groups received liposomes which had been loaded with TNF-, and one group, which received no treatment, served as control.The diameter of the spheroids ranged from 80 m to 350 m. There was no significant difference in growth between the 3 groups treated with free TNF-. Comparing spheroids treated with TNF- with those which had been coincubated with empty liposomes, there was a significant difference (p<0.001) in growth, which correlated with the amount of liposomes. Similarly, free TNF- had a significantly (P<0.001) stronger growth-inhibiting effect as compared to liposomes loaded with TNF-. Comparing the groups treated with liposomes only to those treated with liposomes loaded with TNF-, the latter exhibited a more marked (although not significantly) growth-inhibiting effect.The preliminary conclusion is that the major growth-inhibiting effect seems to be mediated by the liposomes. This phenomenon is in agreement with results obtained in monolayer cultures.  相似文献   
106.
The increased uptake of native serum albumin in tumors is well described. In previous approaches to use this distribution pattern for tumor therapy, albumin molecules were loaded with maximum quantities of antineoplastic drugs. To preserve the properties of native albumin and to avoid enhanced phagocytotic clearance, we used methotrexate (MTX)-albumin-conjugates with a molar loading ratio of 1:1. In this study we evaluated the effects of single injections of MTX-rat-serum albumin (MTX-RSA) containing 50, 20 and 10 mug MTX on 40 BDIX rats bearing O-342 ovarian carcinoma. Tumor volume post treatment and area-under-the-curve of tumor volumes over treatment were compared with an untreated group using the Mann-Whitney U-test. MTX-RSA treatment caused dose dependent effects and in the 50 mug MTX-dosage significant (P 0.01) growth delay. Additional distribution studies with indirectly radio-iodinated MTX-RSA confirmed the prominent tumor uptake of this compound. We conclude that MTX-albumin-conjugates created with optimized labeling techniques and loading ratios cause significant effects even with very low MTX-doses. Thus these compounds may contribute to enhance the efficacy of MTX-treatment.  相似文献   
107.
Objectives: When perinatal medicine emerged as a new medical discipline in the 1960s, Berlin was as one of the world's leading centers. During that time, the city was separated into two parts, each fostering its own health care system. After the destruction of the Berlin Wall, it was possible to speak with the citizens of East Berlin and to access their database systems. This created the singular opportunity to objectively compare the development of perinatal care in both parts of Berlin. Methods: Rates of maternal, perinatal, and infant mortality as well as the rate of preterm deliveries were evaluated over time and between East and West Berlin. The timing of introduction of 20 specific perinatal interventions was evaluated across 18 hospitals with more than 500 deliveries (11 in West Berlin and 7 in East Berlin). Interviews were conducted with 100 gynecologists, 100 midwives, and 100 women who had recently delivered their first child from each side of the city regarding their opinions of the importance of these interventions for the quality of perinatal medicine and how they would distribute a budget to improve maternity care. Results: Maternal, perinatal, and infant mortality decreased in both parts of Berlin until 1990 (p<0.0001), without significant differences between East and West Berlin, though the preterm delivery rate was slightly lower in East Berlin compared with West Berlin (p<0.06). Some new clinical techniques and treatments—such as cardiotocography, ultrasound, tocolytic therapy, and peridural anesthesia—were introduced earlier in West Berlin. In contrast, certain public health measures—such as maternal transport, screening programs for diabetes, and support of breastfeeding—were introduced much earlier in East Berlin. There were significant differences between the beliefs of gynecologists, midwives, and mothers in East and West Berlin. In general, citizens of East Berlin were more enthusiastic about technological medical advances, whereas citizens of West Berlin were more supportive of public health and alternative methods. In addition, there were significant differences between female and male physicians in their beliefs about how to improve health care, regardless of whether they resided in East or West Berlin. Conclusions: The results of this study may serve as a basis for reflection on how different social circumstances and health care policies can influence the improvement of maternal and child health care.  相似文献   
108.
109.
BACKGROUND: Elective coronary artery bypass surgery can be performed with low operative mortality. There is a controversial discussion whether short-term and long-term results of CABG justify this procedure in elderly patients. METHODS: To add to this discussion, we evaluated retrospectively, the clinical profile, operative technique, short- and long-term results of 1127 patients over 70 years of age who underwent myocardial revascularization between January 1985 and December 1996. RESULTS: Mean age of the cohort was 73.9 years and it rose continuously. In 1996, septuagenarians represented 21.5% of our coronary patients, in comparison to 6.4% in 1985. Analysis of risk factors showed an increasing prevalence of renal failure, obesity, hyperuricemia and a history of smoking. Preoperatively, 87% of our patients were in NYHA-class III or IV, and thus operated to relieve severe symptoms. The percentage of emergent operations decreased over the observed period by 10.3%. The internal mammary artery was used with rising frequency (44.8% in 1985-1992 vs 61.5% in 1993-1996). The number of simultaneous valve replacements increased, too. Postoperatively, we noted a rising incidence of respiratory failure (17.1%) and neurological disorders (13.7%). On the other hand, the need for intra-aortic balloon pumping and hemofiltration declined by 6.6% and 2.9%, respectively. Perioperative mortality (< or =24 hrs) was 3.65%, hospital mortality (< or =30 days) was 9.64%. The actuarial survival (standard error) at 1 year was 82% (+/-4.3%), and 65.7% (+/-3.8%) at 5 years. CONCLUSIONS: Our data suggest that coronary artery bypass grafting can be performed in septuagenarians at an acceptable risk. Since the large majority of patients improve symptomatically, surgery is a recommendable option for a growing number of elderly patients suffering from severe angina.  相似文献   
110.
Traumatic lung hernia is a rare diagnosis. A 52-year-old female motorvehicle passenger was admitted as a trauma patient after a motorvehicle accident. She was found to have an incarcerated lung hernia. Size of the hernia, incarceration and respiratory insufficiency mandated immediate surgical intervention with reposition, drainage and stabilisation of the chest wall. The postoperative course was uneventful. The management of the patient is discussed and the available literature reviewed.  相似文献   
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