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41.
An electron-cytochemical investigation was made of oxidation of 3,3-diaminobenzidine (DAB) in the brain of rats and man at different times after death. The oxidation product of DAB was localized in the mitochondria, lipofuscin granules, and erythrocytes. Oxidation of DAB by rat and human brain mitochondria was shown to be only very slightly depressed even 2 days after death.Laboratory of Experimental Pathology and Pathomorphology of the Brain, Institute of Psychiatry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. V. Snezhnevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 757–759, June, 1976. 相似文献
42.
Gerald R. Buzzell Armando Menndez-Pelez Roger A. Hoffman Carmen Rodríguez Isaac Antolin 《Anatomical record (Hoboken, N.J. : 2007)》1994,240(1):52-58
Background: The porphyrin concentrations of the Harderian glands of Syrian hamsters show marked sexual differences, with male levels being much lower than those of females. Porphyrinogenesis is inhibited by androgens, so orchidectomy leads to elevated male porphyrin concentrations; however, a number of other procedures (some of which also lower androgen levels) prevent this. We studied the effects of short-day photoperiods and melatonin on Harderian porphyrin concentrations. Methods: Intact, castrated, or pinealectomized hamsters of both sexes were exposed to long-day or short-day photoperiods. Intact or castrated hamsters were given melatonin injections in the morning or the afternoon, or were given beeswax pellets containing melatonin. After a variable period, Harderian glands were dissected and porphyrins were measured. Results: Prolonged short-day exposure (13 weeks) led to increased Harderian porphyrin concentrations and this rise was prevented by pinealectomy. The rise in Harderian porphyrins following short-day exposure was small, compared with that following castration. Short-day photoperiods also prevented the rise in porphyrin levels associated with castration and this effect was prevented by removal of the pineal. Melatonin injections, whether given in the morning or in the afternoon, had no effect on Harderian porphyrin concentration of castrated male hamsters. Continuous release melatonin pellets reduced the postcastrational rise in porphyrin levels in one experiment, while having no effect in another. In female hamster, neither short photoperiods nor melatonin pellets influenced Harderian porphyrin concentrations. Conclusions: These results suggested that a factor from the pineal gland helps maintain the low levels of porphyrin which are characteristic of male Harderian glands, despite the decrease in androgen levels which typically results from exposure to short days. Morning and afternoon injections of melatonin and continuous release melatonin pellets failed to resolve the question of whether this pineal factor is melatonin. Our results demonstrated that low male and high female porphyrin levels are maintained in Syrian hamsters, despite seasonal variations in the hormonal milieu, suggesting that these sexual differences are important for the (still unestablished) function of the Harderian glands in this species. © 1994 Wiley-Liss, Inc. 相似文献
43.
Primary malignant melanoma of the esophagus 总被引:2,自引:0,他引:2
Dr. Ernst -Dietrich Kreuser 《Virchows Archiv : an international journal of pathology》1979,385(1):49-59
Summary A case of primary malignant melanoma of the esophagus in a 74-year-old male is described. There was a diffuse pigmentation of the lower third of the esophagus macroscopically. Sections from this area revealed melanocytes in the basal layer of the epithelium. This melanosis was not caused by malignant melanoma cells, but obviously by preexisting ectopic and pigmented melanocytes a condition for which the term esophageal melanocytosis is proposed. It is suggested that esophageal melanocytosis as well as the presence of junctional changes may determine the primary nature of malignant melanoma of the esophagus. Furthermore, in order to outline the histologic criteria and the pathological features of primary esophageal melanomas, 64 cases have been reviewed. 相似文献
44.
Nora Ostrzega 《Diagnostic cytopathology》1993,9(4):457-460
The cytologic findings of juvenile papillomatosis (JP) have been rarely described. The clinical and cytologic findings were suggestive of a fibroadenoma, but due to the presence of 2 cc of clear fluid during the aspiration, fibrocystic change was in the differential diagnosis. Operation and subsequent examination of the mass identified a case of JP (so-called Swiss cheese disease of the breast). Because JP is a marker for breast carcinoma for the patients' families, and the patients may themselves be at increase risk for malignancy, it is important that this entity be considered in the differential diagnosis. The observations in this case indicate that it is difficult to diagnose JP only by cytology, but the combination of clinical findings—a well-circumscribed mass in a young patient with cystic fluid, but with a residual mass after aspiration due to the multicystic nature of JP—with the cytologic findings—sheets of hyperplatic breast epithelium with areas resembling fibroadenoma, macrophages, and apocrine cells—that appear to be sufficiently characteristic to suggest the diagnosis of JP. 相似文献
45.
V. Sundaresan P. Ganly P. Hasleton N. M. Bleehen P. Rabbitts 《The Journal of pathology》1993,169(1):43-52
Loss of genetic material, corresponding to chromosomal deletions, has been detected in a wide range of tumours and may indicate the position of a tumour suppressor gene. In order to identify the position of such a gene more precisely, many tumour samples must be studied until a minimum consensus deletion is characterized. This process is particularly necessary for lung tumours in which the deletion in chromosome 3, seen with such high frequencies in all histological subtypes, is almost always large. We have recently described the use of the polymerase chain reaction (PCR) for restriction fragment length polymorphism (RFLP) analysis of DNA isolated from small bronchial biopsies of lung tumours. In this study we adapted this technique to allow genotyping of DNA isolated from paraffin wax-embedded material (PWEM) microdissected from glass slides. We have investigated 12 lung tumours at polymorphic loci on chromosome 3 and showed allelic loss in all samples. In adapting PCR–RFLP analysis for DNA isolated from PWEM, we have concentrated on those approaches which might be adaptable to routine clinical practice. Somatic genetic changes are now being identified in many tumour types, and this information is expected to be of diagnostic and prognostic significance. 相似文献
46.
Physiological detection of deception (“lie detection”) procedures were evaluated with 24 actors, half of whom were “guilty” of a mock-crime and half were “innocent.” All subjects were trained in the Stanislavsky method of acting and were instructed to use this method to appear innocent on the polygraph test. Two versions of the control question detection of deception test were employed: one in which subjects verbally answered immediately following each question and the other in which they delayed their verbal answer for 8 sec following each question. The delayed answer technique allowed the separate measurement of physiological responses to the questions and the answers. Skin resistance responses, cardiovascular changes, and respiration were recorded and analyzed. Excluding inconclusive results, the overall accuracy of the decisions varied between 78% and 91% depending on the test employed. The principal results were: 1) attempts by guilty subjects to appear innocent were totally ineffective, 2) physiological responses elicited by the questions were more valid indicators of deception and nondeception than were the responses elicited by the verbal answers, and 3) errors occurred more frequently with innocent subjects (between 17% and 25% depending on the measure used) than with guilty subjects (0% with each measure). Variables which may affect the generalizability of these results to the field situation are discussed and suggestions for increasing the generalizability of laboratory findings are made. 相似文献
47.
Glomerular changes in BK virus nephropathy 总被引:10,自引:0,他引:10
This study seeks to define the glomerular changes that are associated with human BK virus nephropathy (BKVN). It is based on histopathologic review of 124 biopsies showing light-microscopic changes of viral nephropathy. The diagnosis of BKVN was confirmed by immunohistochemistry or by in situ hybridization. Histological lesions were scored by the Banff 97 criteria for renal allograft pathology and were correlated with clinical parameters. Viral cytopathic effect in the parietal Bowman's capsular epithelium was seen in 21/124 (17%) biopsies. Immunohistochemistry showed infection of Bowman's capsular epithelium in an additional 15/124 (12%) biopsies. Crescents were found in 15/124 (12%) samples. Glomerulitis exceeding grade Banff g1 was only occasionally shown (4/124=3% biopsies). Other pathologic lesions documented include mild increase in mesangial matrix in 23% biopsies, aneurysmal dilatation of glomerular capillaries in 28%, ischemic glomerulopathy in 62%, and chronic transplant glomerulopathy graded as mild (cg1) in 62% of biopsies and as moderate (cg2) in 2/124 (1.9%) biopsies. These findings show that infection of the glomerular epithelium cells can occur in a subset of patients with BKVN, most often in biopsies with high viral load in the tubular epithelium. Isolated crescents can occur in BKVN biopsies, but rapidly progressive glomerulonephritis is not observed. Two biopsies showed electron-dense deposits on ultrastructural examination, but a cause and effect relationship to BK virus infection could not be established. 相似文献
48.
Dr. W. Hofmann Th. Rommel Th. Schaupp F. Seuter J. A. Rossner F. M. Hecht G. Mall 《Virchows Archiv : an international journal of pathology》1980,385(2):151-168
Zusammenfassung In unserer ultrastrukturell durchgeführten Studie wurden Thromben in der Arteria carotis communis von Ratten nach einer zuerst von Meng und Seuter (1977) beschriebenen Methode experimentell erzeugt. Induktion der Thrombusbildung erfolgte in vivo durch Unterkühlung eines kleinen Gefäßabschnittes unter konstantem Druck und kurzfristiger Stase. Eine Änderung des Blutflusses wurde durch einen Silberclip erzeugt. Die geschädigten Gefäßsegmente einschließlich der Thromben bzw. deren Vorstufen wurden nach 5, 10, 30 min und 1, 4 und 24 h nach der Thrombosestimulation entnommen und fixiert. Semidünnschnitte und Ultradünnschnitte wurden im Licht- und Elektronenmikroskop morphologisch untersucht.Den Transformationsvorgängen im Thrombus konnten exakte Zeitmarken zugeordnet werden. Als wichtigstes histopathologisches Merkmal für die Altersbestimmung arterieller Thromben in der Frühphase der Thrombogenese werteten wir die Querstreifung der Fibrinfasern. Diese trat bereits nach 5 min auf, erreichte nach 30 min ein Maximum und verschwand als Folge der zunehmenden Verdichtung der Fasern nach einer Stunde. Nach 4 h sahen wir eine weitgehende Retraktion der Fibrinfasern, die nach 24 h zur Bildung des Fibrinfasergerüstes mit Einmauerung korpuskulärer Elemente führte. Überdies beobachteten wir zwei Thrombocytenaggregate von differenter Struktur. Wir unterschieden ein fibrinarmes Aggregat, in dem die Thrombocyten dichtgepackt und pseudopodienreich erschienen von einem thrombocytenarmen Aggregat mit reichlich interponierten Fibrinfasern. Die nach 5 min im Zentrum des Thrombus auftretende Agglutination der Plättchen im thrombocytenreichen Aggregat führte nach 30 min zur Thrombocytorrhexis und ergab daher einen weiteren Anhalt für die Altersbestimmung des Coagulum. Der entstandene celluläre Abraum stimulierte mononucleäre Zellen und Leukocyten zur Phagocytose. Daher sahen wir nach 4 h eine massive Leukocytose als Folge der frühen Thrombocytorrhexis. Nach 24 h war die viscöse Metamorphose im fibrinreichen und fibrinararmen Aggregat weitgehend abgeschlossen. Innerhalb des beobachteten Zeitraumes entstand eine Verballung und bizarre Deformierung der Erythrocyten, die bereits nach 5 min vom Zentrum des Thrombus ausging und nach 24 h die Peripherie erreichte. Eine Hämolyse der Erythrocyten war nach dieser Zeit noch nicht erkennbar.
Evolution in the early changes in the establishment of arterial thrombi
Summary Ultrastructural studies of thrombi were carried out on the common carotid artery of the rat using a method first described by Meng and Seuter (1977). Induction of thrombus formation in vivo was achieved by chilling of a small vessel segment under constant pressure and short-termed stasis. Disturbance of the blood flow was produced by a silver clip. The damaged vessel segments with the thrombotic deposits were removed 5, 10, 30 min, and 1, 4 and 24 h after stimulation of thrombosis. They were fixed and samples were studied as semithin and ultrathin sections morphologically using light and electronmicroscopy.In the maturation of thrombi exact time intervals could be determined. The most important histopathological characteristics for age determination of arterial thrombi in the early period of thrombogenesis were the cross stripes of fibrin fibres. They appeared after 5 min, reaching a maximum after 10 min and disappeared as a result of increasing fibre density after 1 h. After 4 h nearly complete retraction of fibrin fibres was found which led after 24 h to the formation of a corresponding frame walling in the corpuscular elements. Apart from this aggregation of thrombocytes, which were of two different types were observed, one showing a fibrin-poor aggregate in which the thrombocytes appeared densely packed with numerous pseudopods, and one showing a thrombocyte poor aggregate with abundant interposed fibrin fibres. Agglutination of platelets which occurred in the thrombocyte-rich aggregate in the centre of the thrombus after 5 min led to thrombocytorrhexis after 30 min. The resulting cellular waste stimulated phagocytosis by mononuclear cells and leucocytes. Because of this a massive leucocytosis was found as a result of the early thrombocytorrhexis after 4 h. After 24 h the viscous metamorphosis in the fibrin-rich and in the fibrin-poor aggregate was largely completed. Clumping and deformation of erythrocytes was observed in the middle of the thrombus after 5 min and at the periphery of the thrombus after 24 h. Haemolysis did not occur within this time interval.
Frau Antoni, Herrn Ing. grad. Derks und Herrn Rieger sei für ausgezeichnete technische Assistenz herzlichst gedankt. 相似文献
49.
Jager F Taddei A Moody GB Emdin M Antolic G Dorn R Smrdel A Marchesi C Mark RG 《Medical & biological engineering & computing》2003,41(2):172-182
The long-term ST database is the result of a multinational research effort. The goal was to develop a challenging and realistic
research resource for development and evaluation of automated systems to detect transient ST segment changes in electrocardiograms
and for supporting basic research into the mechanisms and dynamics of transient myocardial ischaemia. Twenty-four hour ambulatory
ECG records were selected from routine clinical practice settings in the USA and Europe, between 1994 and 2000, on the basic
of occurrence of ischaemic and non-ischaemic ST segment changes. Human expert annotators used newly developed annotation protocols
and a specially developed interactive graphic editor tool (Semia) that supported paperless editing of annotations and facilitated international co-operation via the Internet. The database
contains 86 two- and three-channel 24h annotated ambulatory records from 80 patients and is stored on DVD-ROMs. The database
annotation files contain ST segment annotations of transient ischaemic (1155) and heart-rate related ST episodes and annotations
of non-ischaemic ST segment events related to postural changes and conduction abnormalities. The database is intended to complement
the European Society of Cardiology ST-T database and the MIT-BIH and AHA arrhythmia databases. It provides a comprehensive
representation of ‘real-world’ data, with numerous examples of transient ischaemic and non-ischaemic ST segment changes, arrhythmias,
conduction abnormalities, axis shifts, noise and artifacts. 相似文献
50.
H. -O. Wintzer R. Amberg S. von Kleist B. Forster 《Virchows Archiv : an international journal of pathology》1988,413(6):581-589
Summary The postmortem stability of cell antigens has hardly been studied. Using monoclonal antibodies (mabs) we examined the postmortem detectability of lymphocyte surface antigens in different lymphoid organs by comparing two sensitive, immunohistological staining procedures.To quantify the probable degree of autolysis of the tissues a score system was applied by taking into consideration the postmortem age as well as the core temperature of the corpses.The antigens examined generally proved to be very resistant to autolytic influences. Differences were found when comparing different mabs and with regard to the type of lymphoid tissue. The loss of immunohistological reactions was most extensive in the spleen whereas tonsils showed almost no qualitative alterations in staining patterns. Reactivity of mabs with postmortem tissues decreased in the following order: Dako CD22 and anti-Leu 4, anti-Leu 3a, anti-Leu 7, Dako T8. The mabs anti-Leu 7 and Dako-T8 frequently failed to demonstrate their respective antigens but no correlation between the loss of staining and the degree of autolytic decomposition (our score) could be detected.In general, postmortem tissues as well as tissues shock frozen after delay are suitable for qualitative immunohistology of those cells characterized by the mabs applied.The APAAP-method proved unequivocally to be the superior staining technique. 相似文献