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71.
Valérie Finidori-Logli Anne-Geneviève Bagnères Dirk Erdmann Wittko Francke Jean-Luc Clément 《Journal of chemical ecology》1996,22(11):2063-2079
The sexual behavior of the ectoparasitoidDiglyphus isaea is described. Recognition of the female by the male occurs at close range. Males initiate courtship behavior in the presence of a living female regardless of age, as well as in the presence of a female killed by freezing. Courtship behavior is not observed in the presence of a dead female washed with organic solvents but could be elicited using a lure covered with a female organic extract. These findings demonstrate that each sex develops a specific chemical signature that can be dissolved in hexane and transferred to a lure. Analysis of organic extracts by gas chromatography revealed chemical dimorphism between the two sexes. Gas chromatography coupled with mass spectrometry showed that the main components in females were esters of medium-chain fatty acids and long-chain 11-alcohols. There were few hydrocarbons. Female esters, which were present in only small proportions in males, were recovered in the nonhydrocarbon fraction obtained after fractionation of the total extract on a silica-filled microcolumn as a mixture containing 11-heneicosyl, 11-docosyl, 11-tricosyl, 11-tetracosyl, and 11-pentacosyl octanoate, and 11-docosyl, 11-tricosyl, 11-tetracosyl, and 11-pentacosyl decanoate. These results demonstrate that there is a specific gender-related chemical signature. 相似文献
72.
Jean-Luc Zolesio 《电信纪事》1985,40(9-10):495-507
This paper reviews some discret Fourier transform algorithms: the algorithms with prime recursive radix, 2k radix, non regular division, short algorithms, prime factor and Winograd ones are considered. For each of them, the technique to built the algorithm is resumed and algebraic properties on basic ideas used are pointed out. The most important properties of the algorithms are shown underlying the links between criteria choice and implementation of algorithms. In particular, the computational load of the algorithms is analysed. 相似文献
73.
S Stuart B Pfohl M Battaglia L Bellodi W Grove R Cadoret 《Canadian Metallurgical Quarterly》1998,12(4):302-315
The distinction between personality disorder diagnoses is often unclear because of the frequent cooccurrence of one or more of the diagnoses. To date, studies using sample sizes large enough to evaluate the rates of cooccurrence in the less prevalent personality disorders have not been conducted. The Structured Interview for Diagnosis of Personality-Revised, a semistructured instrument designed to yield reliable personality disorder diagnoses, was used to evaluate 1116 subjects for the presence of DSM-III-R personality disorder diagnoses. Cooccurrence rates and odds ratios were calculated for each pair of diagnoses. There was a high degree of cooccurrence between the cluster A personality disorders, between the cluster C personality disorders, and between narcissistic, borderline, and histrionic disorders. In addition, there was also a high frequency of avoidant personality disorders within the cluster A personality disorder diagnoses. Possible explanations for the high degree of cooccurrence and the potential implications for the DSM-IV personality disorder diagnoses are discussed. 相似文献
74.
R Spreafico B Pasquier L Minotti R Garbelli P Kahane S Grand AL Benabid L Tassi G Avanzini G Battaglia C Munari 《Canadian Metallurgical Quarterly》1998,32(1-2):34-48
In this report we describe three patients with developmental cortical abnormalities (generally referred as cortical dysplasia), revealed by MRI and operated on for intractable epilepsy. Tissue, removed for strictly therapeutic reasons, was defined as the epileptogenic area by electroclinical data and stereo EEG (SEEG) recordings. Tissue samples were processed initially for histology, and selected sections were further processed for immunocytochemical investigation in order to determine whether the region of cortical dysplasia was co-extensive with the epileptogenic area. In two patients with nodular heterotopia, disorganized aggregates of neurons (as revealed by neuronal cytoskeletal markers) were found within the nodules. Both pyramidal and local circuit neurons were present in the nodules, but no reactive gliosis was present. When nodules reached the cortex, the cortical layers were disrupted. In the patient with localized cortical dysplasia, a complete disorganization of the cortical lamination was found, and numerous neurons were also present in the white matter. Disoriented pyramidal neurons weakly labelled with cytoskeletal neuronal markers were also present but no cytomegalic cells were found. One of the patients with nodular heterotopia underwent only partial resection of both the 'epileptogenic area' and of the lesion; this patient still presents with seizures. The other patient with nodular heterotopia is seizure-free after a complete lesionectomy and excision of the epileptogenic area. The third patient, with focal cortical dysplasia, had two surgeries; she became seizure-free only after the excision of the epileptogenic area detected by SEEG recording. The present data suggest that the dysplastic areas identified by MRI should not be considered as the only place of origin of the ictal discharges. From the neuropathological point of view, the focal cortical dysplasia can be considered as a pure form of migrational disorder. However, the presence of large aggregates of neurons interspersed within the white matter, in the subcortical nodular heterotopia, suggests that a defect of neuronal migration could be associated with an exuberant production of neuroblasts and/or a disruption of mechanisms for naturally occurring cell death. 相似文献
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78.
PF Plouin G Chatellier C Fumeron C Battaglia X Girerd M Azizi 《Canadian Metallurgical Quarterly》1994,23(31):1439-1445
Screening for renal artery stenoses in hypertensive patients aims at detecting lesions whose treatment (renal revascularization) will normalize or reduce blood pressure and correct or prevent reduced glomerular filtration. Consequently, screening tests such as renal artery duplex Doppler scanning, renal scintigraphy or digital-subtraction angiography are used in patients in whom hypertension is severe, drug-resistant or associated with renal failure. Surgical repair or transluminal angioplasty is not warranted for all stenoses, however, particularly in atheromatous stenoses where these procedures have a 1% mortality, a 10% morbidity and a 30% failure rate to improve blood pressure despite adequate anatomical outcome. Predictors of favourable blood pressure outcome following revascularization are aetiological (fibrous dysplasia rather than atheroma), historical (young age, short duration of hypertension), physiological (renal ischaemia confirmed by scintigraphy, lateralizing renal vein renin ratio) and anatomical (truncal rather than ostial or branch stenoses). Outcome of surgery and transluminal angioplasty has only been documented in retrospective, uncontrolled reports in which blood pressure improvement is overestimated via the placebo effect, habituation to blood pressure readings and optimization of drug treatment, the latter being frequently required despite adequate revascularization. The first prospective randomized trials evaluating angioplasty in atheromatous stenoses are underway and should provide objective information concerning the risk/benefit ratio of this procedure. 相似文献
79.
HP Simmen H Battaglia P Giovanoli E H?nseler J Blaser 《Canadian Metallurgical Quarterly》1995,161(1):23-27
PURPOSE: The maximum preload torque of implant prosthetic retaining screws from four manufacturers and of two alloy types was measured to determine one index of interchangeability of intersystem components. MATERIALS AND METHODS: Implant prosthetic retaining screws from four manufacturers (3i Implant Innovations Inc, West Palm Beach, FL; Impla-Med Inc, Sunrise, FL; Nobelpharma USA Inc, Chicago, IL; and Implant Support Systems Inc, Irvine, CA) and of two metal types (gold and titanium) were investigated using an in vitro simulation model. Five screws of each type were tightened down against a gold cylinder using a Tohnichi BTG-6 torque gauge (Tohnichi American Corporation, Northbrook, IL) until fracture occurred. RESULTS: The 3i Implant Innovations gold and the Nobelpharma gold were not significantly different. The 3i Implant Innovations titanium and the Impla-Med gold were able to withstand less preload torque than the 3i Implant Innovations gold and the Nobelpharma gold. The Implant Support Systems titanium was able to withstand significantly more preload torque than all of the other screws. CONCLUSIONS: Interchanging implant prosthetic retaining screws could introduce new and unknown variables that may affect the long-term survival of implant fixtures and/or the implant prostheses. 相似文献
80.
Nutrition in the fetus and the premature infant is a rapidly changing field, not solely due to the acquisition of new knowledge but also because there have been major conceptual advances that have altered our approach to nutrition during early stages of development. This special report will highlight some of these conceptual advances in this area. 相似文献