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991.
R Kano H Matshushiro T Watari H Tsujimoto A Hasegawa 《Canadian Metallurgical Quarterly》1997,40(9-10):335-341
To develop the molecular differentiation analysis of dermatophytes, we carried out RAPD and Southern hybridization analyses using genomic DNAs of six Arthroderma species, including A. fulvum, A. grubyi, A. gypseum, A. incurvatum, A. otae and A. racemosum. The RAPD analysis gave different band patterns specific to each of the six Arthroderma fungi. However, minor differences in the banding patterns were observed between the strains of plus (+) and minus (-) mating types of A. gypseum, A. fulvum and A. incurvatum. Southern blot analysis using a probe (1S) obtained from A. grubyi DNA gave specific bands only in the DNA samples of A. grubyi and A. incurvatum. On the other hand, Southern blot analysis using a probe (C3) obtained from A. otae DNA gave specific bands in all six Arthroderma species examined, and the size of the bands were specific to each species. These findings indicate that RAPD and Southern hybridization analyses are useful in the differentiation of these Arthroderma species. 相似文献
992.
R Marana GF Catalano P Caruana F Margutti L Muzii S Mancuso 《Canadian Metallurgical Quarterly》1997,12(9):1935-1938
The efficacy of an oxidized regenerated cellulose barrier (Interceed) in reducing postoperative adhesion formation and improving reproductive outcome after ovarian surgery was evaluated in a prospective randomized trial. Twenty-nine New Zealand White female rabbits were submitted to a mid-line laparotomy and a standardized surgical incision was made on both ovaries. At random, one ovary was entirely wrapped in a sheet of Interceed, whereas the contralateral ovary was left uncovered. Four weeks following surgery, the rabbits were mated with a male of proven fertility. Two weeks later, a second-look laparotomy was performed by a blinded observer who evaluated the incidence and score of adhesions, the number of corpora lutea in each ovary, the number of embryos in the ipsilateral uterine horn and also calculated the nidation index for each side. Adhesions were observed in 66% of Interceed-covered and in 97% of control ovaries (P < 0.0001). The adhesion score on the Interceed side was significantly lower than on the control side. The nidation index for the Interceed side was significantly higher than for the control side. The authors conclude that, in the rabbit model, Interceed significantly reduces the incidence and score of postoperative ovarian adhesions and significantly improves reproductive outcome. 相似文献
993.
R Zahn A Vogt K Seidl S Schuster H Gülker KW Heinrich M Gottwik K Neuhaus J Senges 《Canadian Metallurgical Quarterly》1997,86(9):712-721
Balloon angioplasty as the treatment of first choice in the setting of an acute myocardial infarction (AMI) is gaining widespread acceptance because of favourable results from specialised centres concerning high patency rates and low mortality. This study reports the results of angioplasty for AMI at large community hospitals during 1992-1995. 4625 procedures were performed at 68 centres of the Arbeitsgemeinschaft Leitender Kardiologischer Krankenhaus?rzte (ALKK). The age of the patients was 60.8 +/- 11.3 years, with 75.1% men. The infarct related artery was the left anterior descendent in 43%, the right coronary artery in 37%, the circumflex artery in 16%, a bypass graft in 2.3% and the left main stem in 1.4% of patients. The success rate (residual stenosis < 50%) of the intervention was 86%. There was a wide range of procedures per centre, with a median of 40 AMI angioplasties per year and centre. The amount of angioplasties for AMI in relation to all angioplasties performed during this period rose from 5.2% in 1992 to 5.9% in 1995 (p = 0.01). Local complications at the puncture site occurred in 3.2%, with the need for a surgical intervention in 1.1% of patients. In 273 (5.9%) of the patients a second angioplasty was performed during the hospital stay. Aortocoronary bypass surgery was performed in 3% of the patients. Hospital mortality was 9.5% (438/4625 patients). The mortality rate remained constant during the years investigated (1992: 10.6%; 1993: 8.6%; 1994: 9.7%; 1995: 9.8%; p = ns). Higher mortality was observed in older patients, patients with multiple vessel disease, the left anterior descending artery or a bypass graft as infarct related artery as well as in patients with failed reperfusion (residual stenoses > 50%). Hospitals with a case load of more than 40 angioplasties for AMI per year showed a lower mortality as compared to the others. In clinical practice at large community hospitals results of angioplasty for AMI concerning mortality, complications and technical success rate are comparable to those of highly specialised centres. The absolute numbers of angioplasties for AMI increased constantly over the years. 相似文献
994.
Although the functions of serotonin in adult Aplysia have been the focus of numerous investigations, our understanding of the roles played by this neurotransmitter during development is very incomplete. In the previous study (Marois and Carew [1997a] J. Comp. Neurol. 386:477-490), we showed that identified serotonergic cells are present very early during the ontogeny of Aplysia. In order to gain insight into the possible functions that these serotonergic cells may exert, we have used immuno-electron microscopy in this study to examine the projection patterns and target tissues of the serotonergic cells during the larval development of Aplysia. The results indicate that the larval serotonergic cells have numerous and precise connections to non-neuronal and neuronal target tissues: Serotonergic cells innervate the ciliated cells of the velum, numerous muscle systems, possibly visceral organs, and several cells in the central nervous system. Repeated observations of one serotonergic contact onto an undifferentiated neuron in the abdominal ganglion over a short developmental time span suggest that the serotonergic input may trigger axonogenesis in the postsynaptic cell. Apart from this possibility, we suggest that the innervation patterns of the larval serotonergic cells essentially fulfill the same primary function attributed to the adult serotonergic cells, that of modulating ongoing physiological and behavioral activity. 相似文献
995.
Steeves G.M. Elezzabi A.Y. Teshima R. Said R.A. Freeman M.R. 《Quantum Electronics, IEEE Journal of》1998,34(8):1415-1418
A lumped element circuit model for the operation of a junction mixing scanning tunneling microscope (JM-STM) is presented. Fits from this model show excellent agreement with experimental results in the picosecond time regime. The tip sample capacitance employed in the model was calculated to be 33 fF, using the method of images. By varying the capacitance, various tip/sample geometries can be investigated. Testing the response of the model tunnel junction, for faster electrical pulses, suggests how the JM-STM can be pushed into the femtosecond time regime 相似文献
996.
Ehrlichia spp. from human and equine sources in the northeastern Unites States were detected by PCR, isolated, and propagated in the HL-60 promyelocytic leukemia cell line. Growth of Ehrlichia from both equine and human sources was enhanced by addition of retinoic acid, which causes granulocytic differentiation of the HL-60 cells. DNA sequencing of a portion of the 16S rDNA gene supported the hypothesis that the same pathogen was responsible for both equine and human granulocytic ehrlichiosis. 相似文献
997.
Identification of a gene that causes primary open angle glaucoma 总被引:3,自引:0,他引:3
EM Stone JH Fingert WL Alward TD Nguyen JR Polansky SL Sunden D Nishimura AF Clark A Nystuen BE Nichols DA Mackey R Ritch JW Kalenak ER Craven VC Sheffield 《Canadian Metallurgical Quarterly》1997,275(5300):668-670
Glaucoma is a major cause of blindness and is characterized by progressive degeneration of the optic nerve and is usually associated with elevated intraocular pressure. Analyses of sequence tagged site (STS) content and haplotype sharing between families affected with chromosome 1q-linked open angle glaucoma (GLC1A) were used to prioritize candidate genes for mutation screening. A gene encoding a trabecular meshwork protein (TIGR) mapped to the narrowest disease interval by STS content and radiation hybrid mapping. Thirteen glaucoma patients were found to have one of three mutations in this gene (3.9 percent of the population studied). One of these mutations was also found in a control individual (0.2 percent). Identification of these mutations will aid in early diagnosis, which is essential for optimal application of existing therapies. 相似文献
998.
Van Someren E.J.W. Vonk B.F.M. Thijssen W.A. Speelman J.D. Schuurman P.R. Mirmiran M. Swaab D.F. 《IEEE transactions on bio-medical engineering》1998,45(3):386-395
Actigraphy, the long-term measurement of human movement with a small solid state recorder, is gaining acceptance as a useful method in many research fields. Currently available actigraphs assess or estimate the movement duration per time interval. However, the output gives no information on movement type or intensity, and cannot be used in subjects suffering from tremor. The present paper describes a new type of actigraph, that has been developed primarily for the long-term evaluation of motor symptoms in Parkinson patients. The device is the first to discriminate tremor from other movements and to assess both duration and intensity of the two types of movement. It is based on a Motorola 68HC805B6 microcontroller and contains: an accelerometer, programmable gain stages, programmable low- and highpass filters, a programmable level comparator, a peak detector, interface circuits, a real time clock, data storage, and control circuitry. The micro-controller performs a period amplitude sequence analysis (PASA) on the conditioned accelerometer signal, and stores four output variables (tremor duration, tremor amplitude, movement duration, and movement amplitude) at the end of programmable time intervals. The analysis of fluctuations in the motor symptoms of, e.g., Parkinson patients using this actigraph can be of great help in the pharmacological management of symptoms 相似文献
999.
Disasters may strike at any moment in any location. When they do, no distinction is made about the type of firm that is being affected, whether it is a bank or a manufacturing plant. Most firms do not plan for possible disasters, and those that do have typically focused on computer and data contingency planning. In this paper, the focus is shifted to incorporate disaster recovery planning for manufacturing enterprises, especially those that are automated. Automated manufacturing enterprises have characteristics that put them at an increased risk to disasters. The methodological framework proposed in this paper will aid manufacturing organizations and their managers in reducing the risks associated with unanticipated disasters. The framework is termed the “Manufacturing Operations Recovery and Resumption” model. Recommended activities and tools for effective management of this methodology are identified 相似文献
1000.
Gyrotron coaxial resonators with a longitudinally slotted inner cylinder are examined analytically using a surface impedance model, from which expressions for the electromagnetic field, ohmic quality (Q) factor, and characteristic equation of the transverse eigenvalues χ m,p are obtained. The major attributes of such resonators are expressed by the dependence of χm,p on the parameter C-defined as the ratio of the outer to inner radii of the coaxial structure. In that connection, the effect of the corrugation parameters on χm,p is particularly investigated on the basis of an expression derived for the slope function dχm,p,p/dC. It is shown that the χm,p(C) curve may either exhibit oscillatory behavior or present a flat portion over a wide range of C depending on the corrugation parameters chosen. The theory is checked against experiment in which resonant frequencies and total Q factors were measured for TE modes operating in the range of 8-16 GHz in a coaxial cavity with 40 slots. Good agreement is found in that the magnitude of the relative error in frequency is less than 0.5%. Corrugated coaxial resonators prove to be relevant to megawatt gyrotrons where highly selective cavities are required to ensure high conversion efficiency 相似文献