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91.
Antigenic structure of the hexacosapeptide melittin: evidence for three determinants, one with a helical conformation. 总被引:2,自引:0,他引:2 下载免费PDF全文
ELISA-based epitope analysis was performed using rabbit polyclonal antisera against melittin. Antigenic sites were found at the C-terminus, in the middle section and within the N-terminal helix. Antibodies against the helical segment could discriminate between two faces of the amphiphilic helix. The antigenic sites include the bulk of the melittin hexacosapeptide, which is synonymous with a very high epitope density. 相似文献
92.
Invasive pulmonary aspergillosis is characterized by radiological signs allowing a correct diagnosis, including differentiation from pulmonary candidiasis, when they are associated with appropriate clinical symptoms (neutropenia and fever persisting despite broad-spectrum antibiotics). In particular the formation of a pulmonary mycetoma in a previously normal lung is one of these signs. Unlike a simple fungus ball (the saprophytic form of aspergillosis), the rounded density of invasive pulmonary aspergillosis consists of sequestrum of devitalized lung tissue owing to blood vessel invasion by Aspergillus hyphae. This morphologic phenomenon is demonstrated in the present case report and is discussed together with the other roentgenological signs of the invasive aspergillosis. 相似文献
93.
Eva Broberger Carol Tishelman Louise von Essen Eva Doukkali Mirjam A. G. Sprangers 《Quality of life research》2007,16(10):1635-1645
Patients with lung cancer experience considerable distress. Therefore, accurate methods for assessing distress and quality
of life over time may play a key role for managing and evaluating palliative care. Alternatives to commonly used standardized
questionnaires are individual measures. This study prospectively and retrospectively explored the concerns that 46 patients
with inoperable lung cancer spontaneously reported as causing most distress close to diagnosis and 6 months later. Changes
in content individually generated through a structured inductive freelisting were compared with EORTC-QLQ-C30+LC13 ratings.
The results showed that patients perceived a wide variety of concerns as most distressing and that their concerns changed
over time. Between 56 and 62% of these concerns were assessed by items included in the EORTC-QLQ-C30+LC13 questionnaires.
Furthermore, patients’ reports of most distress from fatigue, pain and dyspnea were not always reflected in intensity ratings
of comparable EORTC-QLQ-C30+LC13 items. These results indicate that items included in standardized measures are not always
adequate to assess patients’ concerns, priorities and changes over time. In addition to standardized questionnaires, individualized
measures may be useful in the clinical palliative setting for providing detailed information about the individual’s problems
and prioritizations. 相似文献
94.
Prenatal nicotine exposure selectively affects perinatal forebrain aromatase activity and fetal adrenal function in male rats. 总被引:2,自引:0,他引:2
N I von Ziegler M Schlumpf W Lichtensteiger 《Brain research. Developmental brain research》1991,62(1):23-31
Previous studies have revealed effects of prenatal nicotine treatment on fetal plasma testosterone and perinatal sexual brain differentiation in the rat. In an attempt to further elucidate the processes underlying this action of nicotine, we studied the effect of the drug on brain steroid aromatase which converts androgens to estrogens and is known to be important in sexual brain differentiation. Aromatase activity (AA) was measured by the conversion of [1 beta-3H]-androstenedione to estrone in a brain region comprising preoptic, hypothalamic and amygdaloid areas. In untreated animals, the development of AA between gestational day (GD) 18 and postnatal day (PN) 15 was similar in both sexes, except for a significant drop of AA in female brain at PN6, i.e., during the later part of the critical period for sexual brain differentiation. When time-pregnant rats were treated with nicotine delivered by an osmotic minipump for either one week (2 mg/kg/d or 6 mg/kg/d from GD12) or two weeks (6 mg/kg/d from GD8), their male offspring showed a decrease of AA to female levels at PN6, the sex difference existing at this stage thus being abolished. AA of offspring from dams bearing tartaric acid-containing minipumps or sham-operated at GD8 or GD12 was identical to that of untreated controls. No drug effect was seen in female fetuses and offspring. Sex differences in the developmental effect of nicotine may thus involve brain aromatase. An additional sex-dependent effect of nicotine was observed in the male fetal adrenal axis at GD18. Whether the drug effects on the two steroid hormone systems are interrelated, remains to be elucidated. 相似文献
95.
J. J. E. Vos J. G. Huisman P. W. Modderman A. E. G. Kr. von dem Borne 《British journal of haematology》1987,65(4):447-450
A radioimmunoassay (RIA) for the detection of platelets and platelet fragments was developed. A sandwich of two monoclonal antibodies directed against the platelet-specific glycoprotein complex IIb-IIIa (GP IIb-IIIa) was used in this assay. A discontinuous 7.5-20% (v/v) albumin gradient was applied to separate platelets and their fragments of various sizes. In platelet suspensions fractionated in this way, we observed that particles smaller than normal platelets still carried the GP IIb-IIIa antigens. This procedure enabled us to detect platelet-derived particles in platelet-rich plasma from thrombocytopenic patients. 相似文献
96.
E M Grischke H Anton W Stolz D von Fournier G Bastert 《Acta obstetricia et gynecologica Scandinavica》1991,70(3):225-229
We compared urodynamic findings and results of lateral urethrocystography in 84 case. The aim of the study was to establish a possible correlation between anatomic findings and functional results. Clinically, a significantly greater increase in the normal axis of urethral inclination was noted in patients with a urodynamic diagnosis of stress incontinence than in patients with urge incontinence or for normal urodynamic findings. Lateral urethrocystography vis-à-vis urodynamic assessment proved to be a method having high sensitivity (91%) but low specificity. These two methods supply different but complementary data. Together with the patients' medical history, the assessment of their complaints, clinical vaginal examination, and clinical stress test, they offer valuable information for an efficient therapeutic concept. 相似文献
97.
98.
Sonja A Kotz Stefan Frisch D Yves von Cramon Angela D Friederici 《Journal of the International Neuropsychological Society》2003,9(7):1053-1060
The role of the basal ganglia in syntactic language processing was investigated with event-related brain potentials in fourteen neurologically impaired patients. Seven of these patients had basal ganglia lesions while 7 other patients primarily had lesions of the left temporo-parietal region excluding the basal ganglia. All patients listened to sentences that were either correct or included a verb argument structure violation. In previous experiments this type of violation elicited a biphasic pattern of an N400-P600 complex in young healthy participants. While the N400 may result from incorrect semantic-thematic role assignment, the P600 reflects the fact that verb information does not license the syntactic structure at present. Results of the patient experiment revealed a double dissociation: patients with left temporo-parietal lesions only show a P600, whereas patients with lesions of the basal ganglia showed no P600, but a negativity with extended duration that resembled an N400. The latter pattern not only confirms previous reports that the basal ganglia modulate the P600 but extends these results by showing that the N400 as a late semantic-thematic integration process appears partially modulated by the basal ganglia. 相似文献
99.
100.
Zweiunddrei?ig Patienten mit Metastasenkrankheit der Wirbels?ule, überwiegend von Mammakarzinomen und Plasmozytomen wurden
über 41/2 Jahre operativ dekomprimiert und stabilisiert. Unter Einbeziehung von 5 früh Verstorbenen, betr?gt die mittlere
überlebenszeit 9,5 Monate. Bei Entlassung der überlebenden aus station?rer Behandlung waren mit einer Ausnahme alle Patienten
gehf?hig. In der Regel kamen Verbundosteosynthesen, bevorzugt der ventrale Zugang, zur Anwendung. Die pr?operative Embolisation
war ein unverzichtbarer Bestandteil des Managements. Die operative Behandlung der Wirbels?ulenmetastasen ist eine segensreiche
Methode, die in das gesamte Behandlungskonzept der bedauernswerten Patienten frühzeitig integriert werden sollte. Hochgradige
Paresen oder Paralysen, insbesondere nach fudroyantem Verlauf, nicht kontrollierte Prim?rtumoren und spezielle Tumoren, z.
B. das Bronchialkarzinom sowie gastrointestinale Karzinome, sind auch in der eigenen Serie indikatorisch eher kritisch zu
sehen.
相似文献