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51.
The ability of endosonography (ES) to detect local recurrence after "curative" surgery for rectal cancer was investigated in 65 patients. Fifteen patients developed local recurrence. All of these 15 patients had ES evidence of recurrence; in four cases recurrence was detected by ES alone. Ten of the 15 patients with local failure underwent reoperation. Four patients were candidates for reoperation for cure. Three patients with radical reoperation belonged to the group in which recurrence was detected by ES alone. ES is able to detect small tumors before there is evidence of recurrence in other available forms of examination.  相似文献   
52.
Helicobacter pylori is the causative agent of a variety of gastric diseases, but the clinical relevance of bacterial virulence factors is still controversial. Virulent strains carrying the cag pathogenicity island (cagPAI) are thought to be key players in disease development. Here, we have compared cagPAI-dependent in vitro responses in H. pylori isolates obtained from 75 patients with gastritis, peptic ulcer, and gastric cancer (n = 25 in each group). AGS gastric epithelial cells were infected with each strain and assayed for (i) CagA expression, (ii) translocation and tyrosine phosphorylation of CagA, (iii) c-Src inactivation, (iv) cortactin dephosphorylation, (v) induction of actin cytoskeletal rearrangements associated with cell elongation, (vi) induction of cellular motility, and (vii) secretion of interleukin-8. Interestingly, we found high but similar prevalences of all of these cagPAI-dependent host cell responses (ranging from 56 to 80%) among the various groups of patients. This study revealed CagA proteins with unique features, CagA subspecies of various sizes, and new functional properties for the phenotypic outcomes. We further showed that induction of AGS cell motility and elongation are two independent processes. Our data corroborate epidemiological studies, which indicate a significant association of cagPAI presence and functionality with histopathological findings in gastritis, peptic ulcer, and gastric cancer patients, thus emphasizing the importance of the cagPAI for the pathogenicity of H. pylori. Nevertheless, we found no significant association of the specific H. pylori-induced responses with any particular patient group. This may indicate that the determination of disease development is highly complex and involves multiple bacterial and/or host factors.  相似文献   
53.
Zusammenfassung Die 15jährige Patientin litt wiederholt an Angina, die wohl über einer latenten Sepsis zu einer Endokardveränderung führte. Diese bedingte einen Thrombus des linken Vorhofes in der Gegend der Fossa ovalis. Aus der Zeit rühren embolische Narben der Milz und der linken Niere her. Unter eintretender Organisation des Thrombus wurde er durch den Blutstrom zu einem polypenförmigen Gebilde abgeglättet und ausgezogen. Er reichte nun durch das Ostium venosum sin. hindurch in die linke Herzkammer hinein und täuschte klinisch eine Insuffizienz der Klappe mit Stenose des Ostiums vor. Der organisierte Thrombus entartete in seinem größten Teile schleimig, während der neu angebildete Teil an der Basis auch jetzt noch wie ein typischer organisierter Thrombus aussah. Mikroskopisch konnte ich alle Bestandteile nachweisen, die die Autoren in den Myxomen beschrieben. Auch fand ich entzündliche Elemente, ebenso hyalines Fibrin, besonders in dem jüngeren, basalen Teile des Gebildes. Aus alledem komme ich zur Diagnose Thrombus myxomatodes und meine, daß auch alle die bisher beschriebenen primären Tumoren des endokards, außer den bösartigen Gewächsen, organisierte Thromben darstellen.Mit 5 Textabbildungen.  相似文献   
54.
55.
The accurate quantitation of picogram amounts of TNF is possible by ELISA and is useful in many areas of biomedical research, including studies of TNF release in vitro by stimulated lymphocytes and macrophages, and of serum levels in patients with cancer and sepsis. However, we show in this report that the detection of recombinant TNF standards by ELISA falls over time with incubation at 37 degrees C, and is further decreased when incubated with tumor infiltrating lymphocytes (TIL), making accurate quantitation difficult. We demonstrate that the soluble dimeric form of the TNF receptor can prevent this decrease, both in the presence and absence of TIL. In contrast, the soluble monomeric TNF receptor was much less effective in preventing this decrease. In addition, the dimeric but not the monomeric TNF receptor was found to inhibit bioactivity of TNF as measured by L929 cytotoxicity. The dimeric TNF receptor does not interfere with the detection of recombinant TNF standards by ELISA, and entirely stabilizes TNF levels incubated over 48 h at 37 degrees C in the presence and absence of TIL. This protection is specific, and the TNF receptor does not stabilize interferon-gamma. The dimeric form of the soluble TNF receptor has proven useful in detecting TNF released by TIL transduced with the TNF cDNA that are currently being used in studies of the gene therapy of cancer with TIL. The dimeric TNF receptor may also prove useful in the accurate quantitation of TNF released by stimulated lymphocytes and macrophages in vitro, and in the quantitation of serum TNF levels in patients.  相似文献   
56.
Summary We present a case with a characteristic magnetic resonance image (MRI) of bilateral open-lipped schizencephaly and atypical clinical presentation. The patient is still alive and in good health in her forties, she has never presented seizures, and although the motor dysfunction is well correlated with cerebral lobe involvement, neurobehavioral dysfunction is not proportional to the MR image of the cerebral malformation.
Un cas inhabituel de schizencéphalie bilatérale
Résumé Nous présentons un cas de schizencéphalie bilatérale ouverte caractérisé par une présentation clinique atypique et une imagerie par résonance magnétique nucléaire caractéristique. La patiente est encore vivante, en bonne santé, à plus de 40 ans, elle n'a jamais présenté de crise comitiale et, bien que les troubles moteurs soient bien corrélés aux altérations cérébrales, les troubles neuro-comportementaux ne sont pas proportionnels aux images IRM de cette malformation cérébrale.
  相似文献   
57.
58.
Zusammenfassung 1. Es wird eine Methode zur gleichzeitigen Bestimmung des sog. freien und des proteingebundenen Anteils von in vitro zugesetztem L-Trijodthyronin-131Jod im Serum mittels Dextran-Gel-Filtration angegeben. In der beschriebenen Form ist diese Technik für die routinemäßige Anwendung in der Klinik zur Bestimmung der Bindungs- und Transportverhältnisse von Trijodthyronin geeignet.2. In sog. Verdrängungsversuchen wurde nichtmarkiertes Trijodthyronin dem Inkubationsgemisch von Serum und L-Trijodthyronin-131Jod zugesetzt. Die zugesetzten Trijodthyroninmengen erschöpfen die Gesamtbindungskapazität der Serumproteine in dem gewählten Konzentrationsbereich keineswegs. Im Gegensatz zum Verhalten der prozentualen Anteile des sog. freien und des proteingebundenen Trijodthyronins steigt die absolute Menge des proteingebundenen Trijodthyronins dabei steil an. Man findet eine Kurve, die nicht einer einfachen Sättigunskurve entspricht, sondern eine Resultante aus Sättigungskurven verschiedener Trijodthyronin-bindender Proteine und Verdrängungskurven kompetitiv gebundener Substanzen (z.B. Thyroxin) darstellt.3. Dextran-Gel wirkt nicht als einfaches Molekülsieb für Trijodthyronin. Es greift vielmehr durch Adsorptionsvorgänge kompetitiv in die Serumproteinbindungsverhältnisse des Trijodthyronins ein. Die physiologische Bedeutung des sog. freien Anteils an Trijodthyronin wird diskutiert.4. Die Methode zur Bestimmung des proteingebundenen Jods (PB127I) mittels alkalischer offener Veraschung (Barker) wurde technisch vereinfacht und bezüglich ihrer Reproduzierbarkeit untersucht. Die131Jodausbeute aus zugesetztem L-Thyroxin-131Jod lag bei diesem Verfahren bei ca. 80%.
Summary 1. A method allowing the simultaneous determination in serum of the socalled free and the protein bound part of 1-triiodothyronine-131I added in vitro, using dextran gel filtration, is presented. Assessment of serum protein binding and transport of triiodothyronine can be conveniently performed for clinical purposes by this procedure.2. In socalled discharge experiments non-labelled triiodothyronine is added to incubation mixtures of serum and l-triiodothyronine-131I. The amount of added triiodothyronine did not exhaust the total binding capacity of serum proteins for triiodothyronine. In contrast to the behaviour of the percentages of socalled free and protein bound triiodothyronine the absolute amount of protein bound triiodothyronine was rising linearly with rising concentrations of triiodothyronine added. The curve obtained was interpreted as resulting from saturation curves of different triiodothyronine binding proteins and discharge curves of competitively bound substances, e.g. thyroxine.3. Dextran gel is not acting merely as molecular sieve for triiodothyronine, but rather competing actively with serum proteins for triiodothyronine, adsorbing the latter. The physiological rôle of the socalled free triiodothyronine is discussed.4. With addition of l-thyroxine-131I 80% of131iodine was recovered, when the method ofBarker for determination of serum protein bound127iodine (open alkaline ashing) was used.


Mit Unterstützung der Deutschen Forschungsgemeinschaft.

Herrn Prof. Dr. Dr. h. c.Carl Krauspe in Verehrung zum 70. Geburtstag gewidmet.  相似文献   
59.
Carbamazepine, phenobarbital, phenytoin, and valproic acid are commonly used antiepileptic drugs that show complicated pharmacokinetic behavior Nonisotopic immunoassays are used routinely to monitor these drugs, and assay specificity is important to obtain accurate results. By using samples from subjects receiving each of these antiepileptic medications, competitive immunoassays for them were evaluated on an IMMULITE 2000 automated chemiluminescent analyzer (Diagnostic Products, Los Angeles, CA). Phenytoin assays were evaluated using an additional set of samples from patients with abnormal renal function. All 4 methods were linear, had imprecision of less than 10%, and compared well with other commercial immunoassays. A positive bias was observed for phenytoin measured in samples from uremic patients compared with a high-performance liquid chromatography reference method. The molar cross-reactivity of carbamazepine-10,11-epoxide was 12% in the carbamazepine assay. Phenytoin metabolites and fosphenytoin had substantial cross-reactivity in the phenytoin assay. All antiepileptic drug assays performed well and are suitable for use in monitoring patients receiving antiepileptic drug therapy. One possible exception is the phenytoin assay with samples from patients with renal insufficiency.  相似文献   
60.
Summary Ten healthy sedentary subjects [age, 27.5 (SD 3.5) years; height, 180 (SD 5) cm; mass, 69.3 (SD 6.3) kg] performed two periods of maximal incremental graded cycle ergometer exercise in a supine position. Randomly ordered and using an open spirometric system, one exercise was carried out during normoxia [maximal oxygen consumption ( O2max)=38.6 (SD 3.5) ml·min–1·kg–1; maximal blood lactate concentration, 9.86 (SD 1.85) mmol·l–1; test duration, 22.6 (SD 2.7) min], the other during hypoxia [ O2max=33.2 (SD 3.2) ml·min–1· kg–1; maximal blood lactate concentration, 10.38 (SD 2.02) mmol·l–1; test duration, 19.7 (SD 2.8) min]. At rest, immediately (0 p) and 60 min (60 p) after exercise, counts of leucocyte subpopulations (flow cytometry), cortisol and catecholamine concentrations were determined. At 0 p in contrast to normoxia, during hypoxia there was no significant increase of granulocytes. There were no significant differences between normoxia and hypoxia in the increases from rest to 0 p in counts of monocytes, total lymphocytes and lymphocyte subpopulations [clusters of differentiation (CD), CD3+, CD4+CD45RO, CD4+CD45RO+, CD8+CD45RO, CD8+CD45RO+, CD3+HLA-DR+, CD3CD16/CD56+, CD3+CD16/CD56+, CD 19+] as well as adrenaline, noradrenaline and cortisol concentrations. The counts of CD3 CD16/CD56+-and CD8 +CD45RO+-cells increased most. At 60 p, CD3CD16/CD56+ and CD3+CD16/CD56+-cell counts were below pre-exercise levels and under hypoxia slightly but significantly lower than under normoxia. We concluded that the exercise-induced mobilization and redistribution of most leucocyte and lymphocyte subpopulations were unimpaired under acute hypoxia at sea level. Reduced increases of granulocyte counts during the study and reduced cell numbers of natural killer cells and cytotoxic, not major histocompatibility complex-restricted T-cells, only indicated marginal effects on the immune system.  相似文献   
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