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31.
32.
Background: Abnormalities around titanium stapled sites are not well described in the literature. Existenceof staple granulomas or neoplasms on titanium stapled sites used in TAPP procedures is unknown.Case: We report a case in which differentiation of suspected staple granuloma or neoplasm around a titanium staple,used to secure the mesh in a TAPP procedure, could not be made other than by pathologic examination.Conclusion: This case emphasises that although the appearance of the lesion may be suspected for staple granuloma,the possibility of a malignant neoplasm should always be considered. 相似文献
33.
Cholesterol is important for cell membrane structure and functions as well as for production of steroid hormones and bile acids. It is transported through the body as lipoprotein particles of varying density and composition. Cholesterol homeostasis is maintained through finely tuned mechanisms regulating dietary uptake, hepatic biosynthesis and secretion as well as plasma clearance. Proprotein convertase subtilisin/kexin type 9 (PCSK9) reduces cellular uptake of plasma low-density lipoprotein-cholesterol (LDL-C) by promoting LDL receptor (LDLR) degradation. Two nonsense single-nucleotide polymorphisms (SNPs) at the PCSK9 locus have been associated with life-long hypocholesterolemia and a remarkable reduction of the risk for coronary heart disease (CHD) in African-Americans. These loss-of-function SNPs presumably render PCSK9 less capable of inducing LDLR catabolism, effectively increasing LDLR availability and allowing efficient removal of plasma LDL-C. The combined frequency of heterozygosity for these nonsense SNPs is approximately 3-4% in populations of African descent. Homozygosity for either SNP, which would aggravate hypocholesterolemia, is reportedly rare. Whether such an aggravation would represent a health risk is still a matter of debate. From an evolutionary point of view, the cardioprotective effect of these nonsense SNPs may be a secondary phenotype made evident by the dyslipidemia-inducing lifestyle of today's North America. Their relatively high frequency in African-Americans must be interpreted in the context of the ancestral environment of these subjects in Africa, where diet and lifestyle were presumably less predisposing to atherosclerosis and where parasitic infections were major causes of morbidity and mortality before reproductive age. Parasites feed on host cholesterol for successful infection. The nonsense PCSK9 SNPs may have been positively selected because they reduced susceptibility to severe parasitic infections through cholesterol restriction. If so, these SNPs should be significantly more frequent in Sub-Saharan Africa where parasitic diseases, malaria in particular, have been and still are major selective forces. 相似文献
34.
J. Chr Reidemeister W. Isselhard W. Hasselkus R. Olbrisch U. Müller W. Stock 《Basic research in cardiology》1973,68(1):21-38
Zusammenfassung Ein Verfahren zur Verlängerung der tolerierbaren Ischämiezeit des Myokards stellt der vonBretschneider 1964 angegebene Herzstillstand durch Natrium- und Kalziumentzug und Procaingabe dar. Bisher waren der Sauerstoffverbrauch, der anaerobe Stoffwechsel, die Elektrolytbilanzen, sowie die histologisch morphologischen Veränderungen während der Kardioplegie am Hundeherzen untersucht worden. Für die sichere klinische Anwendung mußte die Erholung des Stoffwechsels nach einem solchen induzierten Herzstillstand analysiert werden. Eine erste Versuchsreihe zeigte, daß am isolierten Kaninchenherzen nach 60 min Ischämie bei 18 °C mit dieser Methode zwar eine gerade ausreichende postischämische Erholung des Stoffwechsels möglich ist, daß aber erhebliche Substratverluste mit der Reperfusion auftreten. Die zweite Versuchsreihe am Hundeherzen in situ ergab eine vollständige Erholung des Stoffwechsels innerhalb der ersten 5 min nach einer Ischämie von 60 min bei 25 °C mit der Methode vonBretschneider. Dabei tritt kein Substratverlust mit der Wiederdurchblutung des Koronarsystems auf. Die Summe der Adeninnucleotide bleibt auch während der 60 min Ischämie völlig konstant.Ein Vergleich der Veränderungen der Substrate und Metabolite des Stoffwechsels während der Kardioplegie mit den anderen bisher auch klinisch verwendeten Verfahren ergibt eindeutig die längsten tolerierbaren Ischämiezeiten bei Anwendung dieser Herzstillstandsmethode, so daß die Methode nach dem augenblicklichen Stand der Kenntnisse als das beste Verfahren zur Durchführung eines induzierten Herzstillstandes, d. h. einer notwendigen Myokardischämie gewertet werden muß.
Mit 3 Abbildungen und 2 Tabellen 相似文献
Summary In 1964Bretschneider introduced a cardioplegia by sodium and calcium depletion and application of procaine which was a new principle for prolongation of the tolerable ischemic period of the myocardium. Untill now the oxygen consumption, the anaerobic metabolism, the electrolyte balances and the histologic changes during this cardioplegia had been investigated in dogs. For a safe clinical use the recovery period after such an induced cardiac arrest had to be evaluated.In a first group of experiments a sufficient postischemie recovery was found after a 60 min period of ischemia at 18 °C with his method of cardiac arrest in isolated rabbit hearts. But a considerable ammount of metabolites was lost during reperfusion with blood.A second group of experiments showed a complete postischemic recovery during the first five minutes after a 60 min period of ischemia at 25 °C introduced by the method ofBretschneider in dogs in situ. There was no loss of metabolites during reperfusion of the coronary system with blood. The sum of adenine nucleotides remained constant throughout a 60 min period of ischemia.The changes of primary substrates and metabolites during this artificial cardiac arrest compared with other clinically introduced methods of cardioplegia showed the longest tolerable ischemic period with the cardiac stand still according toBretschneider. This method must be regarded in the moment as the safest method of induced cardiac arrest for a necessary period of myocardial ischemia.
Mit 3 Abbildungen und 2 Tabellen 相似文献
35.
O Kuchel E Bolté M Chrétien J Chan K Racz J Gutkowska J Hardy 《The Journal of clinical endocrinology and metabolism》1987,64(1):170-174
Yearly episodes of edema, hypokalemia, anxiety, and depression were found to be due to cortisol and deoxycorticosterone surges secondary to a pituitary adenoma in a woman without any of the usual clinical features of Cushing's syndrome. During the long clinical remissions, she had no recognizable laboratory abnormality. She had two episodes in the year following incomplete transphenoidal pituitary tumor resection, but has had none in 2 yr since receiving radiotherapy. The episodes were caused by mineralocorticoid actions of large ACTH-induced increases in cortisol and deoxycorticosterone secretion. A history of episodic edema and hypokalemia, often attributed in women to surreptitious diuretic abuse, requires a careful search for hypercorticism even in the absence of clinical Cushing's syndrome. 相似文献
36.
37.
M. Schuler G. Musekamp J. Bengel M. Schwarze K. Spanier Chr. Gutenbrunner I. Ehlebracht-König S. Nolte R. H. Osborne H. Faller 《Quality of life research》2014,23(9):2531-2543
Purpose
To assess stable effects of self-management programs, measurement instruments should primarily capture the attributes of interest, for example, the self-management skills of the measured persons. However, measurements of psychological constructs are always influenced by both aspects of the situation (states) and aspects of the person (traits). This study tests whether the Health Education Impact Questionnaire (heiQ?), an instrument assessing a wide range of proximal outcomes of self-management programs, is primarily influenced by person factors instead of situational factors. Furthermore, measurement invariance over time, changes in traits and predictors of change for each heiQ? scale were examined.Methods
Subjects were N = 580 patients with rheumatism, asthma, orthopedic conditions or inflammatory bowel disease, who filled out the heiQ? at the beginning, the end of and 3 months after a disease-specific inpatient rehabilitation program in Germany. Structural equation modeling techniques were used to estimate latent trait-change models and test for measurement invariance in each heiQ? scale. Coefficients of consistency, occasion specificity and reliability were computed.Results
All scales showed scalar invariance over time. Reliability coefficients were high (0.80–0.94), and consistency coefficients (0.49–0.79) were always substantially higher than occasion specificity coefficients (0.14–0.38), indicating that the heiQ? scales primarily capture person factors. Trait-changes with small to medium effect sizes were shown in five scales and were affected by sex, age and diagnostic group.Conclusion
The heiQ? can be used to assess stable effects in important outcomes of self-management programs over time, e.g., changes in self-management skills or emotional well-being. 相似文献38.
Die Rezidivierung operierter Mammacarcinome bei db-Inzuchtmäusen und Versuche zu ihrer Beeinflussung
Chr. Hackmann 《Journal of cancer research and clinical oncology》1951,57(4):454-461
Zusammenfassung Die Excision der Mammacarcinome bei db-Inzuchtmäusen verlängert die Lebenserwartung der operierten Tiere gegenüber den nicht operierten. In mehr als zwei Drittel der Fälle kommt es jedoch nach kurzer Zeit zur Bildung neuer Tumoren, und zwar überwiegend an den vorher noch nicht erkrankten Milchdrüsen.Diese Tumoren werden nicht als Absiedlungen des ersten Tumors aufgefaßt, sondern als multiple primäre Tumorbildungen.Eine Inaktivierung des auslösenden Mammatumorfaktors durch immunisierende Maßnahmen, wie sie beim Ehrlich-Impfcarcinom wirksam sind, ließ sich in den vorliegenden Versuchen nicht erweisen. Bei der Implantation von Lebergewebe tumorfreier Mäuse aus niedrigfrequenter Zucht wurde eine Herabsetzung der Tumorfrequenz nach Excision des ersten Tumors beobachtet, die jedoch nicht als signifikant angesehen werden kann.Implantation von Milz sowie von Hoden und ebenso die Ovarektomie ergaben keine Anhaltspunkte für eine Beeinflussung der Tumorfrequenz. 相似文献
39.
Dr. G. Szalay Chr. Meyer A. Schaumberg V. Mann M.A. Weigand R. Schnettler 《Notfall & Rettungsmedizin》2010,13(1):47-51
A 58-year-old man was suffered multiple trauma in a traffic accident. Besides fractures of the extremities, the clinical investigation showed an unstable pelvic injury which was stabilized in the resuscitation room by means of a pneumatic pelvic sling. In a CT of the trunk active bleeding from the liver was detected as well as free liquid in the small pelvis. The dorsal and ventral pelvic rings were anatomically repositioned. An emergency laparotomy was carried out with the pelvic sling still in position and the pelvic injury was stabilized with external fixation afterwards. This case demonstrates that unstable pelvic injuries can be stabilized by applying a pneumatic pelvic sling in the resuscitation room and that anatomical repositioning of the dorsal and ventral pelvic rings becomes possible in a simple way. Further diagnosis and treatment can thus be initiated without delay. 相似文献