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161.
162.
W M Budde J B Jonas J Németh A E Gründler 《Klinische Monatsbl?tter für Augenheilkunde》1999,214(5):300-301
PURPOSE: To evaluate whether the position of the central retinal vessel trunk exit on the lamina cribrosa spatially correlates with the location of parapapillary atrophy in glaucoma. METHODS: Color stereo optic disc photographs of 79 patients with primary or secondary open-angle glaucoma and 53 normal subjects were morphometrically evaluated. We determined the position of the central retinal vessel trunk exit on the lamina cribrosa surface and measured the area of parapapillary atrophy in four 90 degrees quadrants. RESULTS: After correction for normal values, the beta zone area of parapapillary atrophy in the glaucoma eyes was significantly larger, when measured in the disc quadrant most distant to the central retinal vessel trunk exit than as if measured in the quadrant containing the vessel trunk exit. CONCLUSIONS: Position of the central retinal vessel trunk exit on the lamina cribrosa influences the location of parapapillary atrophy in glaucoma. The longer the distance to the central retinal vessel trunk exit, the more enlarged is parapapillary atrophy. 相似文献
163.
In this paper, we present new experimental results which speak of the topic of temporal properties of processes underlying the selection of spatial location. We used the double motion induction paradigm to assess the strength of the selective effects. Prior exposure of an area to flicker, decreased the effectiveness of a cueing spot presented later at that location. This effect lasted for at least 1.5 s. In further experiments, it was found that both static and flickering cues, with time, lose their effectiveness to facilitate processing. While the static cueing decays quickly to very low effectiveness, flicker cueing decays to a level of effectiveness which can be maintained for a long time. Thus with time two flickering cues presented with a temporal offset become equivalent to each other, but remain more effective than a static cue. We conclude that mechanisms coding temporal change determine cue effectiveness for capturing attention. Simple exponential decay functions with different temporal constants and different lower asymptotes can describe these effects. 相似文献
164.
Two types of cone bipolar cells, the blue cone bipolar cell and the diffuse bipolar cell (DB3), were labelled immunohistochemically and investigated in the retina of a New World monkey, the marmoset. Blue cone bipolar cells were labelled with an antiserum against cholecystokinin. Short-wavelength-sensitive (SWS) cones were labelled with an antiserum against the SWS cone opsin. The DB3 cells were labelled with antibodies to calbindin. Blue cone bipolar cells in marmoset do not form a regular mosaic but instead follow the random distribution of the SWS cones. Nevertheless, the SWS cone to blue cone bipolar cell connectivity in marmoset is very similar to that previously described for macaque. In contrast to the blue cone bipolar cells, the DB3 cells form a regular mosaic. The synaptic connectivity of DB3 cells in the inner plexiform layer was analyzed. They make output synapses onto ganglion cells and amacrine cells, and gap junctions with each other. Our results provide further evidence for the existence of parallel bipolar cell pathways in the primate retina and support the view that the retinae of Old World and New World primates have common neuronal connectivity. The random distribution of SWS cones and blue cone bipolar cells is an exception to the general rule of a regular mosaic distribution of cell populations in the retina. 相似文献
165.
Glycine is a major inhibitory neurotransmitter in the mammalian retina and has been shown to influence the responses of ganglion cells. Midget and parasol ganglion cells serve distinct physiological roles in the primate retina and show differences in their response characteristics to light stimuli. In the present study, we addressed the question of whether the expression of glycine receptors differs in midget and parasol ganglion cells. Ganglion cells in the retinae of marmoset and macaque monkeys were injected with Neurobiotin in a live in vitro retinal whole-mount preparation. Retinal pieces were then processed with an antibody against the alpha1 subunit of the glycine receptor. Strong punctate immunoreactivity indicative of synaptic localization is present in the ON and OFF sublamina of the inner plexiform layer. Many of the immunoreactive puncta coincide with the dendrites of both midget and parasol ganglion cells. Immunoreactive puncta are present on distal and proximal dendrites of ON and OFF cells. These results suggest that ON and OFF midget and parasol cells do not differ with respect to the distribution of the alpha1 subunit of the glycine receptor. 相似文献
166.
Fluorine-18 fluorodeoxyglucose positron emission tomography in the follow-up of differentiated thyroid cancer 总被引:4,自引:2,他引:2
Frank Grünwald Axel Schomburg Hans Bender Edzard Klemm Christian Menzel Thomas Bultmann Holger Palmedo Jürgen Ruhimann Beate Kozak Hans-Jürgen Biersack 《European journal of nuclear medicine and molecular imaging》1996,23(3):312-319
Whole-body fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging was performed during the follow-up of 33 patients suffering from differentiated thyroid cancer. Among them there were 26 patients with papillary and seven with follicular tumours. Primary tumour stage (pT) was pT1 in six cases, pT2 in eight cases, pT3 in three cases and pT4 in 14 cases. FDG PET was normal in 18 patients. In three patients a slightly increased metabolism was observed in the thyroid bed, assumed to be related to remnant tissue. In one case local recurrence, in ten cases lymph node metastases (one false-positive, caused by sarcoidosis) and in three cases distant metastases were found with FDG PET. In comparison with whole-body scintigraphy using iodine-131 (WBS) there were a lot of discrepancies in imaging results. Whereas three patients had distant metastases (proven with131I) and a negative FDG PET, in four cases131I-negative lymph node metastases were detectable with PET. Even in the patients with concordant staging, differences between131I and FDG were observed as to the exact lesion localization. Therefore, a coexistence of131I-positive/FDG-negative,131I-negative/FDG-positive and131I-positive/FDG-positive malignant tissue can be assumed in these patients. A higher correlation of FDG PET was observed with hexakis (2-methoxyisobutylisonitrile) technetium-99m (I) (MIBI) scintigraphy (performed in 20 cases) than with WBS. In highly differentiated tumours131I scintigraphy had a high sensitivity, whereas in poorly differentiated carcinomas FDG PET was superior. The clinical use of FDG PET can be recommended in all cases of suspected or proven recurrence and/or metastases of differentiated thyroid cancer and is particularly useful in cases with elevated serum thyroglobulin levels and negative WBS. 相似文献
167.
K. Gründel W. Schwenk B. Böhm J. M. Müller 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1996,381(3):160-164
Zusammenfassung In einer prospektiv randomisierten Studie wurden bei 100 Patienten mit elektiven konventionellen (n=66) oder laparoskopischen (n=34) kolorektalen Resektionen die präoperative Darmvorbereitung mit einer 2 1-Polyäthylenglykol(PEG)-haltigen Lösung plus Prepacol® (Gruppe A, n=50) und die mit einer 4 1-PEG-Lösung (Gruppe B, n=50) verglichen. Im Rahmen der Studie wurde auch der Einfluß der Art und Qualität der Darmvorbereitung auf die Dauer des postoperativen Ileus untersucht. Die Qualität der Darmvorbereitung wurde wührend der Resektion am eröffneten Darm mit einem 4-Punkte-Score durch den Chirurgen bestimmt. Das Zeitintervall vom Ende der Operation bis zum ersten postoperativen Windabgang und dem ersten Stuhlgang wurden dokumentiert. Die Qualität der Darmvorbereitung wurde in beiden Gruppen als gleich gut beurteilt (Gruppe A: 94%; Gruppe B: 84%; p=0,5). Das postoperative Intervall bis zum Abgang von Winden (A: 3,1 ± 1,2 Tage; B: 3,2 ± 13 Tage; p = 0,6) und zum ersten Stuhlgang (A: 3,9 ± 1,3 Tage; B: 4,1 ± 1,3 Tage; p=0,5) war in beiden Patientengruppen etwa gleich lang. Als einziger Faktor mit eigenständigem Einfluß auf die Dauer des postoperativen Ileus in der multivariaten Analyse (Alter, Geschlecht, Vorbereitung, Operationsdauer, Operation, Operationstechnik) wurde die Operationstechnik (laparoskopisch oder konventionell) identifiziert. Der erste Stuhlgang trat nach laparoskopischeu Resektionen bereits nach durchschnittlich 3,2±1,1 Tagen auf, nach konventionellen Operationen dagegen erst nach 4,3±1,2 Tagen (p=0,001). Die Art (41 PEG oder 21 FEG plus Prepacol®) und Qualität der Darmvorbereitung beeinflußten die Dauer der postoperativen Motilitätsstörung nicht.
Effect of bowel lavage with prepacol and polyethylene glycol on the duration of postoperative ileus following colorectal resection
In a prospective randomized study in 100 patients undergoing conventional (n=66) or laparoscopic (n=34) colorectal resection, mechanical lavage with 2 1 of a polyethylene glycol (PEG) solution (group A, n=50) combined with a laxative was compared with lavage with 4 1 of PEG alone (group B, n=50). The influence of bowel preparation on postoperative Hens was investigated. The efficacy of bowel preparation was determined intraoperatively by a surgeon blind to the type of preparation. The time interval between the end of the operation an first flatus or bowel movement was recorded. The efficacy of preparation was no different between the groups (group A: 94%, group B: 84%; P=0.5). The time lapse before first flatus (A: 3.1 ± 1.2 days, B: 3.2 ± 1.3 days; P = 0.6) or bowel movement (A: 3.9 ± 1.3 days, B: 4.1 ± 1.3 days; P = 0.5) also did not differ between the groups. The only factor found in multivariate analysis (age, sex, operation, duration and type of surgery, bowel preparation) to prolong the duration of postoperative ileus was the type of surgery. The first bowel movement occurred 3.2 ± 1.1 days after conventional surgery and 4.3±1.2 days (P<0.001) after laparoscopic surgery. The type of preoperative bowel preparation had no influence on the duration of postoperative Hens. The postoperative interval before the first bowel movement was shorter after laparoscopic surgery.相似文献
168.
Gansauge F Steinbach G Gansauge S König HH Müller J Grünert A Beger HG 《Cancer letters》1998,134(2):193-199
Soluble interleukin-2-receptor-alpha (sIL-2Ralpha) serum concentrations were examined in chronic pancreatitis patients, patients with cystadenocarcinoma of the pancreas, patients with adenocarcinoma of the pancreas and healthy blood donors. sIL-2Ralpha serum concentrations in pancreatic cancer patients were significantly higher than those of normal control subjects or chronic pancreatitis patients. In patients with adenocarcinoma of the pancreas no significant differences were found between sIL-2Ralpha and tumor size, grading, resectability and lymph node involvement. In Kaplan-Meier regression analysis patients with adenocarcinoma of the pancreas with low sIL-2Ralpha levels (<500 U/ml) lived significantly shorter than patients with sIL-2Ralpha concentrations above 500 U/ml (P < 0.01), suggesting that determination of sIL-2Ralpha serum concentrations could provide additional important information about prognosis. 相似文献
169.
H. E. Klein O. Benkert S. Berger G. Gröschl 《European archives of psychiatry and clinical neuroscience》1981,230(4):339-349
Zusammenfassung 32 ambulante Hämodialyse-Patienten wurden über einen Zeitraum von 8 Tagen mehrfach täglich durch psychometrische Fremd- und Selbstbeurteilungsskalen in ihrer Befindlichkeit eingeschätzt. Ziel der Untersuchung war es, depressive Verstimmungen in ihrer Häufigkeit und Ausprägung bei Hämodialyse-Patienten zu erfassen. Es sollte zudem geprüft werden, inwieweit derartige depressive Verstimmungen zur Frage der biochemischen Determiniertheit von depressiven Syndromen beitragen können. Es fanden sich subjektiv erlebte kurzfristige depressive Stimmungsschwankungen in etwa 15% der Fälle, die in den psychometrischen Fremdbeurteilungen jedoch nicht zu objektivieren waren. Derartige depressive Verstimmungen sind somit als Modelldepression für die biologische Depressions-Forschung nicht geeignet. Geringe Häufigkeit und Schwere der depressiven Verstimmungen, sowie psychopathologischer Längs- und Querschnitts-befund lassen die Hämofiltration als wesentlichen Depressionsfaktor im Sinne der Katecholamin-/Indolamin-Mangel-Hypothese unwahrscheinlich erscheinen. 相似文献
170.
J. Grüntzig H. M. Siefert B. I. Wenzel-Hora 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1981,217(2):111-116
In in vivo animal experiments (dog, ape, monkey) the efferent lymph vessels of the conjunctivae and eyelids could be shown as far as the jugular vein by direct and indirect application of Iotasul, a water-soluble X-ray contrast medium.
Zusammenfassung Mit dem wasserlöslichen Röntgenkontrastmittel Iotasul lassen sich im Tierexperiment (Hund, Affe) in vivo die Lymphabflußwege der Bindehaut und der Lider sowohl nach direkter als auch nach indirekter Applikation bis zum Truncus jugularis darstellen.相似文献