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991.
Tilman?T.?ZittelEmail author Klaus?Manncke Stefan?Haug Joachim?F.?Sch?fer Martin?E.?Kreis Horst?D.?Becker Ekkehard?C.?Jehle 《Journal of gastrointestinal surgery》2000,4(6):632-641
We investigated the functional results after laparoscopic rectopexy for rectal prolapse in 29 patients at least 12 months
postoperatively. Twenty patients were evaluated completely pre- and postoperatively (median 22 months postoperatively, range
12 to 54 months). Six patients were interviewed by telephone, two patients were lost to follow-up, and one patient died of
causes unrelated to rectal prolapse. Patients underwent a proctologic examination, anoscopy, rigid sigmoidoscopy, fluoroscopic
defecography, and anorectal manometry pre- and postoperatively, and an additional standardized interview postoperatively.
Anorectal manometry showed a significant increase in maximum anal resting and squeeze pressures postoperatively (resting pressure
72 ±8 vs. 95 ±13 mm Hg, pre- vs. postoperatively; P = 0.046; squeeze pressure 105 ±17 vs. 142 ±19 mm Hg, pre- vs. postoperatively; P = 0.035), and continence improved postoperatively (Wexner incontinence score 6.0 ±1.0 vs. 3.9 ± 0.8 pre- vs. postoperatively,
P = 0.02). Twenty (77%) of 26 patients were satisfied with the operative result, but functional morbidity was observed in four
patients, with two patients complaining of severe evacuation problems. Rectal prolapse recurred in one patient 42 months postoperatively
(recurrence rate 1 [3.8%] of 26 patients). Functional results were very similar to those obtained after open rectopexy, with
symptoms of prolapse and incontinence improved in the great majority of patients.
Presented at the Fortieth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Fla., May 16–19, 1999. 相似文献
992.
Bernhard Olzowy Gregor von Gleichenstein Martin Canis Nikolaus Plesnila Klaus Mees 《European archives of oto-rhino-laryngology》2008,265(11):1329-1333
It is controversially discussed inasmuch acute hearing disorders might originate from impaired cochlear circulation. Hypoxia-specific
alterations of inner ear parameters measurable in patients with acute sensorineural hearing loss would therefore be of great
interest. Aim of this study was to characterize hypoxia-related alterations of the 2f
1−f
2 distortion product. Nine guinea pigs were anaesthetized by i.m. administration of Midazolam, Medetomidin and Fentanyl. For
introduction of hypoxia, the spontaneously breathing animals were offered a gas mixture of N2O and O2 containing either 21 or 12–13% O2. Distortion product otoacoustic emissions (DPOAEs) were continuously monitored at f
2 = 16 kHz; f
2/f
1 = 1, 2; DP-definition = 2f
1−f
2; L
1 = 65 dB and L
2 = 55 dB, while inhaled oxygen was switched from 21 to 12–13% and back. Oxygen saturation (SaO2) was continuously monitored. Data from an hypoxic interval were only used for further data processing if DPOAE levels were
stable before and after hypoxia. Six hypoxic intervals in five animals fulfilled the stability criterion. During the hypoxic
interval with the highest measured SaO2 (75%), no alterations of DPOAE levels were observed. During the remaining five hypoxic intervals, when SaO2 ranged between 57 and 70%, DPOAE levels were on average lower with an increased standard deviation compared to mean pre-hypoxic
levels. Mean decrease correlated with the decrease of SaO2 (r = 0.90, P = 0.014). Alterations followed a characteristic time course—when hypoxia was started, DPOAE levels exhibited a short increase
before they decreased and remarkably destabilized. After re-oxygenation DPOAE levels showed a pronounced level decrease, while
SaO2 already had recovered to pre-hypoxic values. After reaching a minimum, DPOAE levels slowly recovered to pre-hypoxic values.
The decrease of DPOAE levels during hypoxia and the post-hypoxic level alterations have similarly been described by other
authors before, while the distinct destabilization and transiently increased DPOAE levels have not been explicitly mentioned.
A micromechanical mechanism that might explain a transient level increase and the post-hypoxic DPOAE level changes is discussed. 相似文献
993.
Klaus H. Baumann Ludwig Kiesel Manfred Kaufmann Gunther Bastert Benno Runnebaum 《Breast cancer research and treatment》1993,25(1):37-46
Summary Gonadotropin-releasing hormone analogs (GnRH-A) have been added to the armentarium in the therapy of hormone-dependent breast cancer in premenopausal women. The effect of chronic GnRH-A-treatment in premenopausal women is based on the suppression of the hypothalamus-pituitary-ovarian axis and the reduction of sex-steroid serum levels. In addition, a number of experimental and clinical data have been accumulated indicating a direct action of GnRH-A on breast cancer cells and tissue. In this study we analyzed 235 human breast cancer biopsies for specific GnRH-A-binding. We demonstrate high affinity GnRH-A binding sites in human breast cancer tissues. The evaluation of clinical data showed no correlation of the level of GnRH-A-binding with classical tumor parameters. 相似文献
994.
995.
996.
Klaus L. Mohnike Ute Kluba Uwe Mittler Volker Aumann Peter Vorwerk Werner F. Blum 《European journal of pediatrics》1996,155(2):81-86
Abstract The insulin-like growth factor (IGF) signaling pathway may be of importance for the proliferation of different tumours (e.g. breast cancer and Wilms tumour). The bioavailability of both IGF-I and IGF-II is regulated by specific IGF-binding proteins (IGFBPs). IGFBP-2 is the predominant binding protein during fetal life, where it is expressed in most tissues. In contrast, postnatally it is mainly released by specific cell types (hepatocytes, astroglia, kidney cells, prostate cells) and a range of tumour cell lines. Furthermore, phytohaemagglutinin stimulated normal lymphoblasts and malignant lymphoblasts express IGFBP-2. In order to investigate the IGF regulatory pathway in leukaemia serum levels of IGF-I, IGF-II, IGFBP-2 and IGFBP-3 were determined in 28 leukaemic children. Whereas serum levels of IGF-I (mean/range: –2.7/–0.1 to –6.7 SDS), IGF-II (–3.6 SDS/–1.3 to –8.7) and IGFBP-3 (–2.0/+2.2 to –7.1 SDS) were significantly decreased comparable to levels in growth hormone deficiency, IGFBP-2 levels (+4.0/–0.45 to +7.4 SDS) were found to be markedly elevated and inversely correlated to IGF-I (r=–0.51,P=0.013). After haematological remission upon chemotherapy all four parameters had normalized in the 16 re-investigated children. Similar findings have been observed in one boy with a relapse including CNS leukaemia.Conclusion This study demonstrates that the proliferation of malignant lymphoblasts (at diagnosis vs treatment) occurs in the presence of decreased serum levels of IGF-I, IGF-II and IGFBP-3 and that diminished production of these peptides may contribute to impaired growth. It further indicates that serum levels of IGFBP-2 may be directly related to the proliferation of lymphoblasts. 相似文献
997.
Zusammenfassung Menschliche Erythrocyten zeigten sich in der Lage, Galaktose zur fermentativen Reduktion von intracellulär erzeugtem Methämoglobin auszunutzen. Erwachsenerythrocyten kamen mit Galaktose, auf 28%, Erythrocyten von 5–20 Tage alten Neugeborenen auf 66% und Nabelschnurerythrocyten auf 89% der mit Glucose erreichten Reduktionsbeschleunigung.Die geringe Atmung der Erythrocyten war bei Neugeborenen und Erwachsenen nicht different, gleichgültig, ob Glucose oder Galaktose als Substrat vorlagen. Durch Zusatz von Methylenblau wurde in beiden Erythrocytenarten die O2-Aufnahme auf das 8fache gesteigert, wenn Glucose anwesend war. Bei Galaktose als Substrat erfolgte durch Methylenblau lediglich bei Neugeborenenerythrocyten eine Steigerung der O2-Aufnahme (auf das 1 1/2fache); bei Erwachsenenerythrocyten sank die O2-Aufnahme ab.Aus den Versuchen ist abzuleiten, daß Erythrocyten von Neugeborenen Galaktose rascher in Glucose umwandeln als Erwachsenenerythrocyten.Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
998.
Priv.-Doz. Dr. Klaus Seifert 《European archives of oto-rhino-laryngology》1971,200(3):252-274
Zusammenfassung Die Bowman-Drüsen makrosmatischer Versuchstiere wurden nach Perfusionsfixierung der Riechschleimhaut licht- und elektronenmikroskopisch untersucht. Sie Bind zusammengesetzt aus zwei Drüsenzelltypen, die feinstrukturell und offensichtlich auch in ihrer Sekretionsleistung grundsätzlich voneinander unterschieden sind. Sie werden im Detail beschrieben. Die belle Drüsenzelle, vorwiegend im Drüsenfundus zu finden, ähnelt in ihrer Feinstruktur anderen Drüsenzellen mit seröser Sekretion. Die dunkle Drasenzelle bildet große Sekretvacuolen, die auf die PAS-Reaktion stark ansprechen. Das Sekret der Bowman-Drüsen wird durch gerade Ausführungsgänge mit flachem Epithel in die apikale Hälfte des Riechsaumes entleert und bildet hier eine dünnflüssige Grenzschicht zum Luftraum, in der die Riechhaare flottieren.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
Light and electron microscopic studies on the glands of Bowman in the olfactory epithelium of macrosmatic animals
Summary The glands of Bowman in macrosmatic mammalian animals were studied by light and electron-microscopy after fixation of the olfactory mucosa by perfusion. The glands are composed of two types of cells which have a different ultrastructure and also, presumably, a different kind of secretion. The cell types are described in detail. Bright glandular cells are found in the fundus region of the glandular duct; their fine structure resembles that of other glandular cells with a serous-type of secretion. The second type is represented by dark glandular cells which form great droplets of secretion that have a strong PAS-reaction. The secretions of the glands of Bowman empty into the upper portion of the olfactory border through straight ducts having a flat epithelial lining. Here, in the vicinity of the respiratory air space, the secretions form a liquid boundery layer of low viscosity in which the olfactory hairs are submerged.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
999.
1000.
Cultures of exfoliated epithelial cells from different locations of the human urinary tract and the renal tubular system 总被引:1,自引:0,他引:1
Dörrenhaus A Müller JI Golka K Jedrusik P Schulze H Föllmann W 《Archives of toxicology》2000,74(10):618-626
Exfoliated human urinary tract epithelial cells and renal tubular cells from urinary sediments of healthy adults, of urological patients and of internal patients were isolated and cultured. Cells started proliferating within 1 week after seeding a sediment. Proliferating cells formed colonies of different morphologies, designated as type-1 or type-2 cell colonies. Type-1 cell colonies showed irregular contours and spindle-like cells within the colonies. Subcultivation of type-1 cells for up to six passages was possible. Type-2 cell colonies showed smooth-edged contours and subcultivation was not possible. The epithelial character of type-1 cells was demonstrated by positive immunohistochemical staining for cytokeratin-7. In contrast to carbonic anhydrase-positive stained Madin Darby canine kidney cells (MDCK), which were used as positive controls for renal tubular cells, type-1 cells were carbonic anhydrase-negative on staining with the cobalt phosphate method. This indicates that type-1 cells were not of renal tubular origin. Type-2 cells were positively stained for carbonic anhydrase, indicating that type-2 cells were renal tubular cells. Type-2 cell colonies could be assigned to two subgroups with different cell forms. Colonies of cobblestone-like cells more often occurred than type-2 cell colonies with spindle-like cells, which are described in this study for the first time. Colonies with cobblestone-like cells formed domes (hemicysts), whereas spindle-like type-2 cell colonies did not. Cultures of urinary sediments from healthy adults, elderly multimorbid patients treated with furosemide, and urological patients with urolithiasis treated with sulfamethoxazole/trimethoprim and/or with a percutaneous nephrostomy catheter were compared. In 52% of all cultured sediments from healthy adults, in 30% of those from multimorbid patients, and in 75-80% of those from urological patients cells proliferated to colonies. The ratios of type-1 to type-2 cell colonies were 3.3:1 (healthy adults), 1.4:1 (urological patients with urolithiasis), and 1.8:1 (urological patients with urolithiasis, urine was directly collected from the renal pelvis with a percutaneous nephrostomy catheter). Successful cultures of the urinary sediments from these three groups revealed means of 3 or 4 colonies, 14 colonies, and 21 colonies, respectively. Differences in the number of colonies in relation to sex were observed only for the group of urological patients. It was shown that type-1 cells were urothelial cells, which did not show morphological differences due to their locations of origin within the urinary tract, whereas type-2 cells were probably renal tubular cells. These findings offer new aspects in the culturing of human urothelial or kidney epithelial cells with a method based on noninvasive collecting of specimens and requiring only minimal culture effort. The cultures obtained by this method can be used for in vitro studies in toxicological and clinical research. 相似文献