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21.
22.
T F Schwarz A Nerlich B Hottentr?ger G J?ger I Wiest S Kantimm H Roggendorf M Schultz K P Gloning T Schramm 《American journal of clinical pathology》1991,96(1):121-126
Fetal tissues from 16 spontaneous abortions, two terminations, and one perinatal death, 18 of which were associated with maternal human parvovirus B19 infection, were examined for B19 infection by histology and in situ hybridization using a digoxigenin-labeled B19-DNA probe. In 15 spontaneous abortions and one termination, erythroblasts with intranuclear inclusions (lantern cells) reacted with B19-DNA by in situ hybridization. No internal or external fetal malformations were observed. Because 13 (86.7%) spontaneous abortions with lantern cells occurred between the 20th and 28th weeks of gestation, it is postulated that B19 infection may be a particular threat to the fetus during this stage of gestation. 相似文献
23.
24.
Renal excretion of endothelin in children 总被引:1,自引:0,他引:1
István Máttyus L. B. Zimmerhackl A. Schwarz M. Brandis M. Miltényi T. Tulassay 《Pediatric nephrology (Berlin, Germany)》1997,11(4):513-521
Endothelin (ET) is a peptide with profound vasoconstrictive potential. First isolated from porcine endothelial cell supernatant,
it is produced also by smooth muscle, epithelial and circulating cells. Besides vasoconstriction, a wide spectrum of biological
activities of ET (via activation of membrane receptors) has been described. These include regulation of other hormones and
neurotransmitters, cellular growth and proliferation, bronchoconstriction, and, in the kidney, natriuresis and water diuresis.
ET exerts its effects mainly in an autocrine and paracrine fashion. A high concentration of ET is found in urine, compared
with plasma originating mainly from the kidney itself. In this review we focus on the role of urinary excretion of ET in children.
ET excretion was determined under different physiological and pathological conditions. In premature infants and newborns,
the daily excretion of ET (corrected for body surface) was higher than in older children; it was constant, and comparable
to the values in healthy adults after the age of 2 years. Renal ET excretion correlated positively with urine flow in both
healthy and sick children. Conditions with tubular and/or collecting duct cell damage, such as severe hypoxia, hemolytic-uremic
syndrome, renal transplantation, diabetes mellitus, chronic renal failure, and contrast media cytotoxicity were characterized
by elevated urinary excretion of ET. In conclusion, the renal excretion of ET is influenced by several factors, probably reflecting
the intrarenal ET production. ET has a low specificity with regard to renal injury.
Received May 7, 1996; received in revised form January 14, 1997; accepted January 17, 1997 相似文献
25.
On the surface of the free (receptor-unbound) form of hCG, we have previously identified 14 topographically distinct epitopes (Schwarz et al. (1986) Endocrinology 118, 189-197; Berger et al. (1990) J. Endocrinol. 125, 301-309). Here we report that only two of them, i.e. the (adjacent) beta 3 and beta 5 epitopes, can be recognized by 125iodine-labeled monoclonal antibodies when hCG was specifically bound to the rat testis hCG receptor. The exclusive accessibility of precisely these two surface epitopes indicates that hCG assumes a defined rather than a stochastic orientation in its receptor-bound state. The inaccessibility of 12 of 14 epitopes is consistent with the idea that the 341 residues long extracellular domain of the recently cloned hCG receptor (MacFarland et al. (1989) Science 245, 494-499) is the ligand binding domain. It is proposed that the extracellular domain is folded in a way that a cavity is formed large enough to accommodate hCG. Thereby, a considerable portion of the total surface of hCG is covered, as reflected by the masking of most of its epitopes. 相似文献
26.
In einer prospektiven Studie zentraler Talusfrakturen wurden radiologische Daten (Nativr?ntgenbild, CT, MRT) auf ihre Korrelation
zum histologischen Befund (Biopsie zum Zeitpunkt der Schraubenentfernung) überprüft. Bei 9 Frakturen an 8 Patienten (Alter
14 – 48 Jahre) handelte es sich um Frakturen des Typs Hawkins I und II je einmal sowie des Typs III viermal; in 3 weiteren
F?llen lagen K?rperfrakturen vor. Innerhalb von 24 h nach dem Unfall wurden 7 Frakturen verschraubt und 2 mit Bohrdr?hten
adaptiert. Das verletzte Bein wurde für 14 – 53 Wochen post trauma vollst?ndig entlastet. Die Beobachtungszeit betrug mit
einer Ausnahme 2 Jahre oder mehr; 4 Patienten zeigten am letzten R?ntgenbild einen intakten Talus, 4 Patienten zeigten partielle
Einbrüche des Talusdoms und in 1 Fall war ein Teileinbruch fraglich. Die histologische Untersuchung (16 – 52 Wochen post trauma)
zeigte in allen F?llen osteozytenfreien origin?ren Knochen mit Anlagerung neuen Knochens in individuell recht unterschiedlichem
Ausma?. Das Hawkins-Zeichen war in 6 F?llen partiell positiv, sowie je einmal positiv und einmal negativ. Im CT konnte sowohl
Dekalzifikation als auch Frakturheilung besser als im R?ntgenbild beobachtet werden. Das MRT-Signal war 5mal normal, 2mal
partiell und einmal komplett pathologisch. Positives Hawkins-Zeichen und normales Signalverhalten sind prognostisch günstig
zu werten. Es kam jedoch in Folge zentraler Talusfraktur auch bei radiologisch günstigem Verlauf zur Osteonekrose wenigstens
von Teilen Talus gefolgt von schleichendem Ersatz. Die offenbar bei jeder zentralen Talusfraktur gest?rte Vaskularisation
wurde von keinem radiologischen Befund einwandfrei reflektiert.
相似文献
27.
Summary A prospective study was undertaken to determine the value of scintigraphy in predicting nonunion or necrosis of the femoral head following femoral neck fractures. Scintigraphy was carried out in 49 patients before operation and in 37 one week after operation; in 18 it was done before and after operation. The uptake of isotope was estimated visually as either normal or reduced compared to the opposite side. All the patients were followed up for at least 2 years. The results indicate that pre-operative bone scintigraphy is useful in elderly patients to predict nonunion and necrosis, and therefore is recommended to select those patients who will benefit from primary arthroplasty instead of fixation of the fracture.
Résumé Etude prospective de la valeur de la scintigraphie dans la prévision des complications tardives après fracture du col du fémur. Une scintigraphie a été réalisée avant l'intervention chez 49 patients et une semaine après chez 37 autres; dans 18 cas elle a été faite avant et après l'opération. La concentration d'isotopes a été évaluée visuellement et considérée comme normale ou comme diminuée par comparaison avec la hanche opposée. Tous les patients ont été suivis deux ans au moins. Les résultats permettent de penser que la scintigraphie pré-opératoire est un examen utile chez les sujets âgés présentant une fracture du col avec déplacement pour prédire pseudarthrose et nécrose de la tête fémorale. Elle permet de choisir les patients pour lesquels l'arthroplastie est préférable à l'ostéosynthèse.相似文献
28.
A plasmid encoding streptomycin-resistance could be detected in 13 of 32 Pasteurella multocida-cultures isolated from cattle and swine. The plasmid of these cultures proved to be similar upon Southern blot hybridization. It could be transformed into Escherichia coli 490A, where it also expressed streptomycin resistance. 相似文献
29.
30.
R Snyder J Bishop G Brodie W Burns A Coates J Levi D Raghavan M Schwarz M Tattersall D Thomson 《Cancer treatment reports》1987,71(3):273-276
Epirubicin was studied in a phase I setting to find the maximum tolerated dose when given weekly for 3 of 4 weeks. Forty-one evaluable patients were treated in groups at doses increasing from 20 to 45 mg/m2. The highest dose level produced the maximum degree of myelosuppression (lowest neutrophil count, 1.9 X 10(9)/L; range, 0-3.7) recorded on Day 22. This was well-tolerated in this group of mainly pretreated patients. Nonhematologic side effects were minimal. This dose schedule allows a greater dose per unit time to be administered than other recommended schedules for epirubicin. 相似文献