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151.
Localization of CEA,HCG, Lysozyme,alpha-1-antitrypsin,and alpha-1-antichymotrypsin in gastric cancer and prognosis 总被引:1,自引:0,他引:1
Ch. Wittekind R. Wachner W. Henke S. von Kleist 《Virchows Archiv : an international journal of pathology》1986,409(5):715-724
Summary Carcinoembryonic antigen (CEA),-human chorionic gonadotropin (HCG), alpha-1-antichymotrypsin (ACT), alpha-1-antitrypsin (AAT) and Lysozyme (LYS) were traced by immunoperoxidase staining in gastric carcinomas. The immunohistological results were evaluated in relation to histological types (WHO and Laurén), stage of disease, grade and survival time. CEA was demonstrated in 96% of the tumours, HCG in 34%, ACT in 78%, AAT in 42%, and LYS in 71%. Comparing the staining patterns of the antigens and the intensity of staining some differences were notable. Except for signet-ring cell carcinomas, all of which were intensively positive, CEA expression decreased significantly with loss of differentiation. This observation was not seen with the other marker substances. None of the tested markers was characteristic for one particular histological type, nor could they be correlated with the tumour stage or grade. The marker positivity of CEA, ACT and LYS was not related to survival time. For HCG only, a correlation between tissue expression and a restricted survival time was established. Patients with AAT positive carcinomas had a significantly better survival probability. 相似文献
152.
Quantitative Evaluation of the Blood-Brain Barrier Capacity to Form Dopamine from Circulating L-DOPA
J. E. Hardebo L. Edvinsson Ch. Owman E. Rosengren 《Acta physiologica (Oxford, England)》1977,99(3):377-384
The ability of the blood-brain barrier to form dopamine from increasing doses of systemically administered L-DOPA has been studied in rats by a combination of chemical determination of dopamine, and histo-chemical and cytofluorometric measurements of L-DOPA and dopamine. The break-through of L-DOPA from the circulation into the brain parenchyma via the enzymatic blood-brain barrier was estimated by comparing the amount of newly formed dopamine in the caudate nucleus-putamen and in the cerebellum. The capillaries were found to efficiently trap L-DOPA in their walls, and an upper limit was reached (at an administered i.p. dose of 100 mg/kg of L-DOPA). It could be estimated that approximately 3 % of the total dose of L-DOPA given was decarboxylated by the blood-brain barrier. The possible influence by the regional differences in perfusion of the two regions seen after administration of L-DOPA was ruled out in measurements of local cerebral blood flow using the 14C-ethanol technique. 相似文献
153.
Zusammenfassung An vier gesunden jugendlichen Versuchspersonen wurde für den Multifidus-Anteil des M. erector trunci die Häufigkeit synchroner Entladungen zweier differenter Faseraktionspontentiale bei ein- (rechts-) und beidseitiger Ableitung untersucht. Die Beobachtungen genügten den Bedingungen für eine statistische Auswertung. Die Häufigkeit synchroner Impulse wurde durch die prozentuale Differenz der errechneten (= zufälligen) abzüglich der gezählten (= beobachteter) Koinzidenzen ausgedrückt. Die so erhaltenen Mittelwerte (Synchronisationsraten) lagen — in Entsprechung zu den von Buchthal für die Extremitätenmuskeln erhobenen Werten — sowohl für die einseitigen wie für die beidseitigen Ableitungen zweier differenter Aktionspotentiale unter ±10%. Ein signifikanter Unterschied der Synchronisationsrate bei den einzelnen Versuchspersonen fand sich nicht, ebenso keine Beziehung zwischen der Häufigkeit synchroner Entladungen und der mittleren Frequenz. Für die ausgewerteten Beobachtungen wurde die AS-Dauer bei leichter Halteaktivität bestimmt. In einzelnen Fällen konnte eine vollkommene Synchronisation zweier Motoneuronen-Entladungen und eine Abhängigkeit der Aktionspotentiale vom Atemcyclus beobachtet werden.Mit 6 TextabbildungenDie Untersuchungen wurden mit Unterstützung der Deutschen Forschungs-gemeinschaft durchgeführt. 相似文献
154.
The present study reports the maturation of behavioral responses to several classes of auditory stimulation and defines both natural and artificial stimuli to which kittens respond. This development is discussed relative to the physical maturation of the external auditory canal and the pinna and the extant electrophysiological and neuroanatomical literature. The external auditory canal did not reach its maximum depth until 12 ± 3 days of age and this was followed by a gradual deepening of the external concavity resulting in the complex adult pinna being formed at around 31 days of age. All but two of the animals showed diffuse pinna movements to tactile, visual and olfactory stimulation on the first post-natal day. The kittens showed a definite response to auditory stimuli by 5 ± 1.5 days. In all cases, the early responses consisted of a general arousal, bouts of pinna movements and facial squints. In general the earliest responses were seen to the tape recorded natural stimuli. Seventy-five percent of the animals responded to all stimulus presentations by 7 days of age, but showed adult latencies only at 14 days. Some degree of spatial localization appeared as early as 10 days, but 75% of the subjects showed this at 16 days with adult latencies coming in at 26 days. It was within this latter period that the animals began to show habituation to the non-animal sounds. These results demonstrate, by using a battery of both natural and artificial auditory stimuli, a diffuse reactivity in the neonatal kitten which suggests that the immature auditory system is quite capable of mediating simple behaviors before central connections are either electrophysiologically or anatomically mature. 相似文献
155.
Nutzung von Gen5 und Gen6 ts-Mutanten des Phagen T3 für die Anzeige von Hemmstoffen der DNS-Synthese
In an enzyme-specific drug screening system nalidixic acid and 3'FTdR, inhibitors of DNA synthesis, both reduce the growth of wild type and temperature-sensitive point mutants of phage T3 with different efficiencies. The wild type shows the strongest sensitivity against the drugs, while an exonuclease mutant is the most insensitive variant. The DNA polymerase mutants exhibit an intermediate degree of inhibition. The anthracycline antibiotics violamycin BI and adriblastin which preferentially inhibit RNA synthesis show the same degree of inhibition for all mutants. This is true also for the RNA synthesis inhibitor lambdamycin, which is identical with chartreusin. The protein synthesis inhibitors chloramphenicol and o-phenanthroline, a chelating agent, impair all mutants to the same extent. Our data confirm the hypothesis that structural variants of essential viral enzymes, when compared with the wild type should sensitivities against specific inhibitors and show that this T3 system could be used for the indication of specific inhibitors of DNA synthesis. 相似文献
156.
K. H. Scholz J. Marten Ch. Herrmann U. Spaar U. Tebbe K. L. Neuhaus H. Kreuzer 《Journal of molecular medicine (Berlin, Germany)》1990,68(16):823-829
Summary According to several reports of close correlations between pulmonary artery pressure and ANF plasma levels it would be convenient to replace invasive pressure monitoring by ANF determination.Mean pulmonary artery and right atrial pressures and pulmonary artery as well as peripheral venous ANF plasma concentrations were measured in 24 patients before and after coronary angioplasty (PTCA) continuously at rest and during exercise: At rest, both pressure and ANF-values remained unchanged before and after PTCA. At exercise, there was a decrease of mean pulmonary artery pressure (from 41.3±8.6 to 31.5±7.4 mmHg,p<0.001), mean right atrial pressure (from 11.9±3.0 to 9.0±2.3 mmHg,p< 0.001), pulmonary artery (282.5±191.0 to 207.3±157.2 pg/ml,p<0.05) and peripheral venous (112.7±48.0 to 97.1±53.2 pg/ml, n.s.) ANF concentration after PTCA. We found no correlation between PTCA-induced changes of right arterial pressures and ANF concentrations, while changes of pulmonary artery pressures were significantly correlated to changes of peripheral venous (r=0.79,p<0.001) as well as pulmonary artery (r=0.59,p<0.01) ANF concentrations at exercise. In 6 of the 24 patients, however there was an inverse relationship between changes of pulmonary artery pressures and ANF concentrations. — Our data demonstrate a significant correlation between changes of ANF plasma level and pulmonary artery pressure values at exercise after PTCA. In the individual case however invasive pressure monitoring cannot be replaced by determination of ANF plasma levels.
Abkürzungsverzeichnis ANF Atrialer natriuretischer Faktor - PTCA Perkutane transluminale Koronarangioplastie - PPa mittlerer pulmonalarterieller Druck - PPc mittlerer pulmonalcapillärer Druck - PRA mittlerer rechtsatrialer Druck Herrn Prof. Dr. med F. Scheler zum 65. Geburtstag gewidmet 相似文献
Abkürzungsverzeichnis ANF Atrialer natriuretischer Faktor - PTCA Perkutane transluminale Koronarangioplastie - PPa mittlerer pulmonalarterieller Druck - PPc mittlerer pulmonalcapillärer Druck - PRA mittlerer rechtsatrialer Druck Herrn Prof. Dr. med F. Scheler zum 65. Geburtstag gewidmet 相似文献
157.
158.
Rodolphe Thiébaut Jérémie Guedj Hélène Jacqmin-Gadda Geneviève Chêne Pascale Trimoulet Didier Neau Daniel Commenges 《BMC medical research methodology》2006,6(1):38-9
Background
Mathematical models are widely used for studying the dynamic of infectious agents such as hepatitis C virus (HCV). Most often, model parameters are estimated using standard least-square procedures for each individual. Hierarchical models have been proposed in such applications. However, another issue is the left-censoring (undetectable values) of plasma viral load due to the lack of sensitivity of assays used for quantification. A method is proposed to take into account left-censored values for estimating parameters of non linear mixed models and its impact is demonstrated through a simulation study and an actual clinical trial of anti-HCV drugs. 相似文献159.
The release of [3H]γ-aminobutyrate (GABA) neosynthesized from [3H]glutamine was estimated in one substantia nigra and in the ipsilateral thalamus of halothane-anesthetized cats by perfusing a [3H]glutamine-enriched physiological medium through a push-pull cannula implanted in the two structures under investigation. After two hours of superfusion, muscimol (10?6 M) was delivered through the nigral push-pull cannula for 50–60 min and local- and distal-evoked changes of [3H]GABA release were analyzed. In some experiments, changes of global neuronal activity induced by muscimol application were recorded in different thalamic nuclei, using a bipolar electrode. In a few of the above experiments, biochemical and electrophysiological determinations were simultaneously performed in the substantia nigra and the thalamus. The nigral application of muscimol (10?6 M) induced locally an activation of the substantia nigra reticulata cells, as well as an increase in release of [3H]GABA.Distally, in the thalamus, two types of biochemical and electrophysiological responses were observed according to the localization of the tip of the push-pull cannula or the electrode. (1) An increased release of [3H]GABA and a depression of the global multi-unit cellular activity were obtained in the ventralis medialis-ventralis lateralis, the centralis lateralis and the paracentralis nuclei. These effects could reflect an activation of the GABAergic nigrothalamic neurons projecting to these different thalamic nuclei. (2) In contrast, in the medialis dorsalis paralamellar zone adjacent to the intralaminar nuclei of the thalamus, a decrease of [3H]GABA release and an activation of the multi-unit activity were obtained. These latter results may suggest either a polysynaptic response or the non-GABAergic nature of the nigrothalamic neurons afferent to the medialis dorsalis paralamellar zone. 相似文献
160.
H. Erkkilä Ch. Raitta M. Iivanainen E. Taskinen H. -A. Unnérus M. Gummerus 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1985,222(3):134-138
The condition called lactation optic neuritis has been previously considered a clinical entity of its own. Four women, who developed optic neuritis within 1–12 months while breast-feeding their infants, were investigated ophthalmologically and neurologically in order, to find specific clinical features for this condition. The course of the disorder was similar to classic optic neuritis without lactation. The clinical history and laboratory findings in three of the four patients suggested a demyelinating disorder. It is possible that the decreased immunosuppressive activity just after pregnancy induces the manifestation of an underlying demyelinating disease. The existence of lactation optic neuritis, however, is questioned as a separate entity of its own. Lactation together with decreased immunosuppression may merely act as a provocateur in the onset of optic neuritis, which in many cases is the first clinical manifestation of incipient multiple sclerosis. 相似文献