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61.
62.
EF Solomayer IJ Diel D Wallwiener S Bode G Meyberg M Sillem C Gollan MD Kramer U Krainick G Bastert 《Canadian Metallurgical Quarterly》1997,76(6):812-818
The "attentional model" of time estimation assumes that temporal judgments depend on the amount of attention allocated to the temporal processor (the timer). One of the main predictions of this model is that an interval will be judged shorter when attention is not allocated to the temporal parameters of the task. Previous studies combining temporal and nontemporal tasks (dual-task method) have suggested that the time spent processing the target duration might be a key factor. The less time devoted by the subject to the temporal task, the shorter the judged duration. In the two experiments presented here, subjects were asked to judge both the duration of a visual stimulus and an increment in intensity occurring at any time during this stimulus. In the second experiment, trials without intensity increments were added. The main result is that the judged duration was shorter when the increment occurred later in the stimulus or did not occur. In those cases, subjects had been expecting increment occurrence during most part of the stimulus and thus had focused for a shorter time on stimulus duration. We propose that attention shifts related to expectancy and to detection of the increment reduce subjective duration. 相似文献
63.
C Chabannon K Cornetta JP Lotz C Rosenfeld M Shlomchik S Yanovitch JP Marolleau G Sledge G Novakovitch EF Srour B Burtness J Camerlo G Gravis J Lee-Fischer C Faucher I Chabbert D Krause D Maraninchi B Mills L Kunkel F Oldham D Blaise P Viens 《Canadian Metallurgical Quarterly》1998,78(7):913-921
Seven chlorine-containing orcinol derivatives (2-8) and orcinol (9) have been isolated from diseased bulbs of the edible lily Lilium maximowiczii, and their structures have been elucidated. Six of the chlorinated orcinol derivatives (2, 4-8) showed antifungal activity. Because organochlorine compounds are rare in terrestrial higher plants, their biosynthetic origin was examined. These compounds were shown to be induced in intact bulb scales by UV irradiation or by inoculation with the pathogenic fungus Fusarium oxysporum f. sp. lilii. Biosynthetic studies suggested that these "natural organochlorine pesticides" are produced by enzymatic chlorination of orcinol (9) with chloroperoxidase and hydrogen peroxide, which are both induced in the plant tissue under stress conditions. 相似文献
64.
CJ Lacey HS Thompson EF Monteiro T O'Neill ML Davies FP Holding RE Fallon JS Roberts 《Canadian Metallurgical Quarterly》1999,179(3):612-618
A fusion protein vaccine consisting of human papillomavirus 6 L2E7 with Alhydrogel was developed for the treatment of genital warts. Twenty-seven subjects with genital warts received 3 immunizations over 4 weeks in an open-label study. The vaccine was well-tolerated, and all subjects made serum IgG antibodies, predominantly IgG1, against L2E7. Nineteen of 25 tested persons made antigen-specific T cell proliferative responses to L2E7, and peripheral blood mononuclear cells when cultured with L2E7 in vitro produced both interferon-gamma and interleukin (IL)-5, although IL-5 predominated after the final vaccination. Five subjects completely cleared warts within 8 weeks. Subjects whose warts were not cleared by 8 weeks were offered conventional therapy. Recurrence of warts was not seen in any of the 13 persons whose warts cleared by vaccine alone or with conventional therapy. While these preliminary results of the use of this therapeutic immunogen are encouraging, proof of efficacy will require randomized double-blind trials. 相似文献
65.
66.
An acute pulpalgia and temporomandibular disorders can produce many of the same symptoms. To illustrate identification of an acute pulpalgia as a component in TMD, the authors review the evaluation of 11 patients at a clinic that specializes in TMD treatment. During the evaluation, thermal testing and periodontal ligament anesthesia were used to identify the offending tooth. After receiving endodontic treatment or having the tooth extracted, patients reported either complete or partial relief of TMD symptoms. The authors provide questions that may help practitioners identify a tooth with an acute pulpalgia as a contributing factor to TMD symptoms and suggest a technique to confirm this diagnosis. 相似文献
67.
Peptides labelled with the fluorophore cyanine 3 were used to study naturally expressed neuropeptide receptors by confocal microscopy in continuous cell lines, primary cultures, and unfixed tissue. Swiss 3T3 fibroblasts bound cyanine 3-gastrin-releasing peptide at 4 degrees C, and internalized the peptide after 10 min at 37 degrees C. Internalization was specific, since it was blocked by incubation with unlabelled peptide. Primary cultures of myenteric neurons of the guinea pig incubated with cyanine 3-substance P at 4 degrees C had specific surface labelling. After 30 s at 37 degrees C, the peptide was internalized into vesicles in both the soma and neurites. Direct observation of live neurons showed movement of fluorescent vesicles to a perinuclear region after 30 min. Endocytosis was associated with a loss of surface binding sites. Unfixed whole mounts of guinea pig and rat ileum were incubated with cyanine 3-neurokinin A at 4 degrees C. After 5 min at 37 degrees C, Cy3-neurokinin A was specifically internalized in neurons and smooth muscle cells. After 30 min, a perinuclear labelling occurred in some cells. Labelling in rat neurons was diminished by the NK3-R antagonist SR142801. Thus, cyanine 3-neuropeptides are valuable tools to study expression and endocytosis of naturally expressed receptors. 相似文献
68.
A technique is described for using the internal mammary artery to bypass the left anterior descending coronary artery and another adjacent coronary artery even when the alignment of the two vessels is not favorable for a conventional sequential graft. The distal end of the mammary artery is amputated and used to construct a Y graft to the anterior descending artery and to the secondary target vessel. 相似文献
69.
PURPOSE: To describe the occurrence, cause, and significance of hemoptysis following thrombolytic therapy for acute myocardial infarction. PATIENTS AND METHODS: We retrospectively reviewed 2,634 patients presenting with acute myocardial infarction who received thrombolytic therapy to determine the incidence of hemoptysis. Chart and radiographic review included the type, dose, and route of thrombolytic therapy. In addition, the onset, duration, and severity of hemoptysis were recorded and correlated with radiographic and bronchoscopic findings. RESULTS: Eleven patients (0.4%) developed hemoptysis following administration of thrombolytic therapy for an acute myocardial infarction. The duration and severity had a wide range, although no patient had significant hemodynamic compromise. The source of hemoptysis was identified in only one patient who had a tongue laceration following cardiopulmonary resuscitation, and blood was seen within the oropharynx and trachea. No definitive cause was identified in all other patients. There was no correlation between the different types or doses of thrombolytic therapy and the duration or severity of hemoptysis. Chest radiographs were nonspecific and demonstrated resolution within 11 days following hemoptysis. CT of the thorax in one patient and bronchoscopy in two patients confirmed chest radiographic findings and in no patient was an underlying pulmonary abnormality identified. CONCLUSIONS: Pulmonary hemorrhage and hemoptysis are unusual complications of thrombolytic therapy in patients with acute myocardial infarction. Although hemoptysis may be the first indicator of an underlying pulmonary abnormality, we found no case in which a significant abnormality was unmasked. This study suggests that follow-up chest radiographs are recommended and further evaluation may be unnecessary if complete resolution is demonstrated. 相似文献
70.
PURPOSE: Retrospective studies suggest that adult patients with intractable epilepsy may have a history of febrile seizures in childhood. Risk factors for a febrile seizure may include the rate of increase in the core temperature (T-core), its peak (Tmax), the duration of the temperature increase, or an underlying brain pathology. Recently, neuronal migration disorders (NMD) have been diagnosed with increasing frequency in patients with epilepsy, but the link between NMD, febrile seizures, and epilepsy is unclear. We studied rat pups rendered hyperthermic to ascertain the incidence of seizures, mortality, and extent of hippocampal cell loss in each group. METHODS: We exposed 14-day-old rat pups with experimentally induced NMD (n = 39) and age-matched controls (n = 30) to hyperthermia (core body temperature > 42 degrees C). RESULTS: The incidence of hyperthermia-induced behavioral seizures and mortality rate were significantly higher in rats with NMD than in controls (p < 0.05). The longer duration of hyperthermia resulted in a higher incidence of behavioral seizures and higher mortality rate (p < 0.05). In rats with NMD, hyperthermia resulted in hippocampal pyramidal cell loss independent of seizure activity; the extent of neuronal damage correlated positively with the duration of hyperthermia. In control rats, occasional neuronal loss and astrocytosis occurred only after prolonged hyperthermia. CONCLUSIONS: In immature rats, NMD lower the threshold to hyperthermia-induced behavioral seizures and hyperthermia in the presence of NMD may cause irreversible hippocampal neuronal damage. 相似文献