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51.
DG Avode B Bouteille F Houngbe C Adjien C Adjide D Houinato A Hountondjl M Dumas 《Canadian Metallurgical Quarterly》1998,39(1):60-61
Retroperitoneal extravasation is an extremely uncommon complication of duodenal ulcer perforation. The preoperative diagnosis is difficult and may even by missed at operation. There were 25 cases reported in the literature. Only one patient was correctly diagnosed preoperatively and only seven patients survived. We describe the first case of retroperitoneal extravasation from perforated duodenal ulcer presenting as scrotal sepsis. 相似文献
52.
Quinine and quinidine are reported to potentiate the behavioural effects of serotonergic agents and monoamine uptake inhibitors. We have therefore investigated the presynaptic actions of quinine and quinidine on monoamine uptake and release in rat brain tissue in vitro. Quinidine evoked the release of [3H]5-HT, [3H]noradrenaline and [3H]dopamine from pre-loaded rat brain slices in a concentration dependent manner with EC50 values of 175, 486 and 150 microM, respectively. Quinine induced [3H]monoamine release with similar potencies. Both quinine and quinidine also inhibited the active uptake of [3H]5-HT, [3H]noradrenaline and [3H]dopamine into rat brain synaptosomes with IC50 values in the range 0.13-12.4 microM. The potency of each drug to inhibit [3H]5-HT uptake was significantly higher than that for [3H]noradrenaline or [3H]dopamine. The relative potency of quinidine compared to quinine was more marked in the case of [3H]5-HT (58-fold) than for [3H]noradrenaline (3-fold) or [3H]dopamine (4-fold). The inhibition of [3H]5-HT uptake by quinine and quinidine was competitive in nature and corresponded with the potencies of these drugs to inhibit [3H]paroxetine binding. No correlation was observed between the potencies of quinine and quinidine to induce the release of [3H]monoamines and to inhibit their uptake, suggesting that these effects are mediated by two distinct mechanisms. We conclude that the presynaptic actions of quinine and quinidine on monoamine uptake and release may be implicated in their potentiation of the effects of serotonergic agents and uptake blockers. 相似文献
53.
MA Piplani DG Disler TR McCauley TJ Holmes JP Cousins 《Canadian Metallurgical Quarterly》1996,198(3):855-859
PURPOSE: To determine the accuracy of semiautomated quantification of articular cartilage volume from three-dimensional (3D) reformations of magnetic resonance (MR) images. MATERIALS AND METHODS: Sagittal, fat-suppressed, 3D, spoiled gradient-recalled-echo MR imaging of two bovine and two human cadaver knees was performed. Articular cartilage volume was calculated from 3D reformations of the MR images by using a semiautomated program written at the authors' institution. Calculated volumes were compared with directly measured volumes of the surgically removed articular cartilage. RESULTS: The percentage of error of the MR imaging-determined volumes was 6.53% +/- 4.75 (mean +/- standard deviation). A strong correlation between the two sets of observations was shown (r=.997). Linear regression showed the calculated volumes to be highly accurate (slope=1.002, P>.25). Repeated reformations yielded volumes that were reproducible (mean absolute error, 0.013 mL +/- 0.019) and not significantly different from the measured volume (P>.10). CONCLUSION: Semiautomated quantification of knee articular cartilage from MR images yields highly accurate cartilage volumes. 相似文献
54.
In the retinas of teleost fish dopamine, released from interplexiform cells, modulates synaptic transmission at both the chemical and electrical synapses of retinal horizontal cells. This modulation is due to activation of adenylate cyclase and phosphorylation by protein kinase A, perhaps of the synaptic ion channel proteins themselves. In this study we have fractionated the white perch retina by Percoll density gradient centrifugation in order to identify proteins which coenrich with horizontal cells. In addition we have tested retinal fractions for phosphorylation by native cAMP-dependent kinase. Our findings indicate that there are at least 3 proteins of molecular weights 28, 43/44 and 50 kDa which coenrich with horizontal cells and 3 proteins of 30/31 kDa, 35 kDa (putative rhodopsin) and 48 kDa (putative arrestin) which coenrich with photoreceptor fractions. The 43/44 kDa phosphoprotein is a target for cAMP-dependent protein phosphorylation and thus is apparently an element of the dopaminergic modulatory pathway in perch horizontal cells. 相似文献
55.
Wolfgang Luf und Ernst Brandl 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1988,186(4):327-332
Zusammenfassung Zur Bestimmung der Annatto-Farbstoffe Norbixin und Bixin in Käse wird eine derivativspektroskopische und eine HPLC-Methode vorgeschlagen. Beide Methoden kommen mit einer raschen und einfachen Probenaufbereitung aus, da eine Abtrennung von-Carotin und Fett nicht erforderlich ist. Die Probenaufbereitung besteht aus einer Extraktion der Farbstoffe mit Aceton, Filtration, Eindampfen des Extraktes, Entfernen von Restwasser durch Zusats von einigen Millimetern absolutem Alkohol und anschließendem Eindampfen, Aufnehmen in Chloroform/Eisessig (99,5 + 0,5) für die Derivativspektroskopie bzw. Aceton für die HPLC. Die derivativspektroskopische Methode erlaubt sowohl die qualitative Analyse (Nachweisgrenze unter 0,67 mg/kg abhängig vom natürlichen-Carotingealt), als auch eine Quantifizierung. Sie kann deshalb sowohl als Screeningmethode zur Kontrolle der rigorosen österreichischen Vorschriften, als auch zur Kontrolle der Einhaltung von Höchstwerten verwendet werden und zeichnet sich weiters durch eine kurze Analysenzeit (75 s) und geringem Materialaufwand aus. Die HPLC-Methode gestattet einerseits eine Auftrennung der Komponenten Norbixin und Bixin als auch eine separate quentitative Erfassung der in Schnittkäse anzutreffenden Carotinoide wie-Carotin,-Apo-8-Carotinal und-Apo-8-Carotinsäureethylester (Nachweisgrenze für Norbixin und Bixin 0,2 mg/kg). Die dafür erforderliche Analysenzeit beträgt 20 min. Die HPLC-Methode wird für Bestätigungszwecke bei Vorliegen geringer Bixin-Norbixinkonzentrationen bzw. als Alternative vorgeschlagen.
Detection of annatto dye-stuffs, norbixin and bixin, in cheese by means of derivative spectroscopy and high performance liquid chromatography (HPLC)
Summary A derivative spectroscopic method and a HPLC-method are described for the determination of the annatto dye-stuffs, norbixin and bixin, in cheese. Both methods enable a simple and quick sample preparation since the separation of-carotene and fat is not required. The sample preparation step consists of extraction with acetone, filtration, evaporation of the extract and separation of water residues by the addition of a few milliliters of absolute ethanol. This is followed by evaporation and extraction of the residual solution with chloroform/acetic acid (99.5 + 0.5) for the derivative spectroscopic method or with acetone for the HPLC method. The qualitative detection (detection limit greater than 0.67 mg/kg, depending on the genuine-carotene content) as well as the quantitative determination is possible by means of the derivative spectroscopic method. Therefore, this technique may be used within the rigorous Austrian regulation or for controlling the quantities and limits of annatto dye-stuffs in cheese, if its application is allowed. The method also has the advantage of quick detection (only 75 s) and saving of material used. The HPLC method allows for the separation and quantification of norbixin and bixin as well as the other carotenoids such as-carotene,-apo-8-carotenal and-apo-8-carotenoic acid — ethylester, which may also be found in varieties of cheese (detection limit of norbixin and bixin: 0.2 mg/kg). The time required for the separation of the above mentioned substances is 20 min and the HPLC method is proposed for the confirmation of low concentrations of these substances.相似文献
56.
57.
DG Hall 《Canadian Metallurgical Quarterly》1994,65(5):1299-1317
4 experiments examined 3- and 4-year-olds' interpretations of novel words applied to familial objects in the sentence frame, "This Y is X," where X is a novel word, and Y is a familiar basic-level count noun (e.g., "dog," "cup"). These novel words are ambiguous and could be interpreted either as proper names (e.g., "Fred") or as adjectives/mass nouns (e.g., "red"/"lead"). The experiments addressed 2 questions. First, do children appreciate that the words can be construed either as proper names referring to individuals or as adjectives/mass nouns referring to salient properties/material kinds? The results showed that children could easily make either interpretation. Second, what factors affect children's tendency to make either a proper name or an adjective/mass noun interpretation? In the experiments, children learned the novel words for a range of animals and artifacts. Most children who learned the words for typical pets (e.g., a bird) made proper name interpretations, as did the majority of those who learned the words for certain non-pet animals (e.g., a caterpillar) described as possessed by someone, but only about half of those who learned the words for such non-pet animals not so described. Very few children who learned the words for either simple (e.g., a shoe) or complex (e.g., a boat) artifacts made proper name interpretations. The results provide clear evidence of the role of semantic information in constraining children's interpretation of a novel word, and they help to refine an understanding of what counts as a nameable individual for preschoolers. 相似文献
58.
59.
DD Stapleton TC Moffett DG Baskin JB Bassingthwaighte 《Canadian Metallurgical Quarterly》1995,2(3):277-282
OBJECTIVE: Provide regional flow measurement in the hearts of small mammals using a new, higher-resolution technique based on the deposition of a molecular marker. METHODS: We determined the instantaneous extraction and retention of the "molecular microsphere" radiolabeled desmethylimipramine in retrogradely perfused hamster hearts. In a separate series of experiments, autoradiography was used to measure regional myocardial deposition densities in hamster hearts of about 0.5 g with spatial area resolution of 16 x 16 microns. RESULTS: Radiolabeled desmethylimipramine is almost 100% extracted during a single transcapillary passage and is retained in the tissue for many minutes. Autoradiographic images demonstrated a spatial flow heterogeneity with standard deviations of 31 +/- 4% of the mean flow (N = 5) in 16 x 16 x 20-micronm3 voxels. This is equivalent to the projections made using fractal relationships from cruder observations obtained with microspheres in the hearts of baboons, sheep, and rabbits. CONCLUSIONS: Autoradiography using a molecular deposition marker provides quantitative information on myocardial flow heterogeneities with resolution at the size of cardiac myocytes. Because the regions resolved are smaller than the volume of regions supplied by single arterioles, the results must slightly exaggerate the true heterogeneity of regional flows. 相似文献
60.
We have reported that acute cardiac allograft rejection is associated with increased numbers of donor-reactive helper T lymphocytes (HTL) in the peripheral blood of patients. Further, increased frequencies of circulating donor-reactive HTL may predict allograft rejection episodes diagnosed by endomyocardial biopsy. The present study evaluates the relationship between donor-reactive HTL and allograft "acceptance" in cardiac transplant recipients bearing long-term allografts (> 1 year). Patients were categorized as either long-term acceptors or persistent rejecters based on the number of rejection episodes and the ability to withdraw steroid therapy. Limiting dilution analysis for IL-2-producing HTL was utilized, with cadaver donor splenocytes as a source of donor alloantigens. Donor-reactive HTL frequencies were determined from peripheral blood samples obtained before transplant, and at 1 month and 1 year after transplant. Individuals who accommodated their allografts and were withdrawn from steroid therapy had reduced numbers of donor-reactive HTL at 1 year after transplant as compared with earlier time points. Further, PBMC obtained from these individuals at 1 year after transplant responded weakly to donor alloantigens in a mixed lymphocyte response (MLR). This relationship between donor-reactive HTL and allograft accommodation was exemplified in a cardiac/liver transplant patient who was diagnosed with progressive multifocal leukoencephalopathy and removed from all immunosuppression. No subsequent rejection episodes were diagnosed. Donor-reactive HTL were not detectable and this individual failed to mount an MLR to donor alloantigens. However, a vigorous donor-reactive response was observed when MLR cultures were supplemented with exogenous IL-2. Therefore, nonresponsiveness to the allograft appeared to be due to a deficit in IL-2 production. In contrast, patients who experienced persistent rejection episodes and required continued steroid therapy maintained large numbers of donor-reactive HTL at 1 year after transplant. PBMC from these individuals responded vigorously to donor alloantigens in an MLR. Hence, monitoring donor-reactive HTL may identify individuals who have accommodated their graft and may tolerate a reduction in immunosuppression. 相似文献