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991.
A susceptibility locus (IDDM2) for Type I (insulin-dependent) diabetes mellitus has been identified as allelic variation at a variable number of tandem repeats polymorphic region upstream of the human insulin gene. In Caucasian populations, individuals homozygous for the short length alleles (26 to 63 repeats: class I) have a two- to fivefold increased risk of developing the disease, while the long alleles (more than 140 repeats: class III) are dominantly protective. Recent evidence has shown that class I alleles are not equally predisposing, and in particular, the 42-repeat allele (allele 814) can be protective when paternally inherited. We have assessed the contribution of IDDM2 to disease in a group of Basque families with Type I diabetes. As in other Caucasoid populations, we found that class I alleles, as a whole, are associated with an increased risk of developing the disease. Using a polymerase chain reaction-based assay to more accurately resolve the different sizes of individual class I alleles, we identified 14 different variants and observed that allele 814 has an anomalous behaviour in Basques, being the only class I allele that does not have an increased frequency in the diabetic alleles group. These findings provide additional support for the recently published allele-specific effects of IDDM2 in Type I diabetes pathogenesis. 相似文献
992.
J Calvo Cascallo N Mundi Salvadó M Cardona Fontanet 《Canadian Metallurgical Quarterly》1993,45(2):41-44
When in some selected patients, a direct arterial surgery (DAS) procedure or an endoluminal surgery (ES) are required for a chronic arterial ischemia (III or IV degrees), and an arteriography with contrast is absolutely contraindicated (because of severe renal failure without hemodialysis program or a severe congestive heart failure or a hyperthyroidism or a seriously demonstrated hypersensibility against the contrast agents); an angiography by digital subtraction with carbon dioxide (DIVAS-CO2) is indicated. This technique provides good quality images with minimal risks for the patient and an adequate study for ulterior treatment. We report a case of a 67-years-old woman, with diabetes-II, ischemic cardiopathy, arterial hypertension and a demonstrated hypersensibility against the iodide compounds. The patient was admitted because of a chronic ischemia (IV degree) with ischemic ulcerations on some fingers from the left foot. High doses of analgesic drugs were needed. Because the hypersensibility against the iodide compounds, an angiography with CO2 was carried out. The good quality images provided by this technique showed the factibility of a revascularization. 相似文献
993.
994.
Lourdes Amigo Agustín Olano Marta M. Calvo 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,200(4):293-296
The effect of CO2 on the growth of psychrotrophic milk spoilage organisms was studied, both in raw fresh milk and in pure cultures of three species ofPseudomonas growing in sterilised milk. Changes of sensory properties of CO2-treated samples after heat treatment were also analysed. Inhibition of psychrotrophic growth at 7 °C in milk treated with CO2 to a pH 6.2 or 6.0 was impaired by a gradual reduction of the CO2 content during storage. Growth inhibition was considerably improved by pH adjustment at 24-h intervals. Sensory analysis showed significant differences between non-acidified and acidified samples after heat treatment at 75 °C for 20 s or 110 °C for 5 min. No sensory differences were found between non-acidified and acidified milks degassed before heat treatment.
Konservierung von Rohmilch mit Kohlendioxid. Sensorische Untersuchung wärmebehandelter Milch
Zusammenfassung Es wird der Einfluß von CO2 auf das Wachstum von psychrotrophen Milchfäulnisorganismen in frischer Rohmilch bzw. in reinen Kulturen von drei Spezies von in sterilisierter Milch wachsendenPseudomonas untersucht. Auch die Veränderungen in den sensorischen Eigenschaften nach der Wärmebehandlung der mit CO2 behandelten Proben werden untersucht. Die Hemmwirkung auf das von Psychrotrophen bei 7 °C in durch CO2 auf pH 6.2 bzw. 6.0 eingestellte Milch schwindet durch die allmähliche Abnahme an CO2 während der Lagerung. Der hemmende Einfluß steigt erheblich durch tägliche Einstellung des pH-Werts. Die sensorischen Analysen zeigten signifikante Unterschiede zwischen nicht angesäuerten und angesäuerten Proben nach einer Erhitzung auf 75 °C für 20 s bzw. 110 °C für 5 min. Es konnten jedoch keine signifikanten sensorischen Unterschied zwischen nicht angesäuerter und angesäuerter Milch, die vor der Hitzebehandlung entgast worden waren, beobachtet werden.相似文献
995.
Beln Calvo Santiago Celma Ma Teresa Sanz Pedro A. Martínez 《Microelectronics Reliability》2004,44(7):1189-1198
In this paper a new CMOS transconductor structure based on a gm-boosted degenerated differential pair is presented for applications in the video frequency range. The proposed circuit combines two techniques, a switchable array of source degenerating MOS resistors and a programmable output current mirror, in order to widen the Gm tuning range while maintaining linearity. Degeneration MOS resistors are made common-mode voltage independent thanks to a simple control circuit. Post-layout simulation results from a 0.35 μm design supplied at 3.3 V show a wide tuning range (10–100 MHz), good linearity (−58.4 dB for an output signal voltage of 1.1 Vp–p) and low excess phase (<0.5° over the whole tuning range). 相似文献
996.
M. L. Calvo A. Manzanares M. Chevalier V. Lakshminarayanan 《Image and vision computing》1998,16(14):1003-1017
We discuss a formalism to characterize degraded edge images formed in a diffraction limited system (with circular pupil of unit radius) under conditions of incoherent illumination. We introduce a novel definition of degraded edges and consider this approach to model a basic optical mechanism involved in the perception of visual depth and edge detection. We introduce a degradation parameter to quantize the degree of edge blur. We present a generalization of such a procedure by assuming the Heaviside function to be a systematic generator of degraded edges. We reproduce experimentally the predictions made by the formalism proposed herein. 相似文献
997.
A new 3D exhaustive ray tracing algorithm for microcells is presented. This algorithm, based on an intelligent sequence search and Fermat's principle, overcomes some of the limitations of `brute force' ray tracing and image theory 相似文献
998.
E Hortelano Martínez J Calvo Catalá MI Gonzalez-Cruz Cervellera E Ortega González M Riera Ayora I Valero Prieto A Herrera Ballester 《Canadian Metallurgical Quarterly》1997,14(5):241-243
BACKGROUND: To study the seroprevalence of hepatitis C virus in a cohort of six patients with a diagnosis of polyarteritis nodosa (PAN). METHODS: There have been included six patients with a diagnosis of PAN, carrying out a serodiagnosis of hepatitis B virus (VHB) and C (VHC) this last one by means of the following methods: ELISA, RIBA-II and PCR. RESULTS: These cases (50%) showed exclusive positivity to VHC by means of the three ways of diagnosis, two cases showed positivity to VHB (33.3%), one case (16.6%) showed positivity to both virus (VHB and (VHC) and one case didn't show positivity virus. CONCLUSIONS: It is probable a ethipatogenic relation between hepatitis C virus and polyarteritis nodosa, our sample doesn't show any difference from that written in the literature. The positive rheumatoid factors can give false positive for VHC by means of the technique ELISA because of this it is necessary to confirm the positive by means of the techniques RIBA-II and PCR. 相似文献
999.
1000.
Joaquim M.F. Dos Santos Teresa H.V.T. Dias Santiago D.A. Reyes Cortes C.A.N. Conde 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1989,280(2-3):288-290
A xenon-filled gas proportional scintillation counter for X-ray spectrometry using low-cost designing techniques is described. This detector has a basic energy resolution of 8.3% for 5.9 keV photons. X-ray fluorescence spectra are presented for a variety of samples. 相似文献