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911.
The Neurospora crassa Asm-1+ (ascospore maturation 1) gene encodes an abundant nucleus-localized protein required for formation of female structures and for ascospore maturation. Deletion mutants of Asm-1+ are "ascus-dominant," i.e., when crossed to wild type, neither Asm-1+ nor Asm-1 delta spores mature. To explain this behavior, we considered three models: an effect of reduced dosage of the gene product, failure of internuclear communication, and failure of transvection (regulation dependent on pairing of alleles). We found that for proper regulation of subsequent sexual sporulation, Asm-1+ must be in proximity, probably paired, to its allelic counterpart in the zygote: i.e., transvection must occur. Disruption of pairing causes failure of ascospore progeny to mature. Transvection in Neurospora, unlike in Drosophila, occurs immediately before meiosis, and can be demonstrated between wild-type alleles. 相似文献
912.
BM Fernández 《Canadian Metallurgical Quarterly》1996,7(2):48-54
Being part of the first report of the SEEIUC Forum on the training of nurses in critical care units, this article shows the different postgraduation training paths which Spanish legislation establishes. The "Titulos Oficiales de Especialización Profesional" ("Official Degrees on Professional Specialization") settle the seven nursing specialties regulated by the Decreto 992/1987. Following a second path, "Titulos de Postgraduado no Oficiales" ("Non-official postgraduation degrees"), every University acknowledged by the LRU and creating them as their Own Degrees, may organize Master courses, University experts, University specialists and Postgraduation university degrees, according to their autonomy. So that this autonomous offer is as homogeneous as possible, there is an interuniversity agreement which encompasses 24 national universities and gathers the general criteria for the academic organization of such courses. The report is completed by an analysis of the training offer for critical care nursing, developed during the 1995/1996 course in Spain. 相似文献
913.
I Pechán 《Canadian Metallurgical Quarterly》1996,97(7):397-405
Exact and early diagnosis of acute myocardial infarction is essential for the subsequent routine management of this frequent cardiovascular disease. At present, the clinical biochemistry possesses a set of more or less cardiospecific protein markers for early detection of myocardial ischemic damage. After the admission of patient to the hospital, serial estimations of rather non-specific enzyme activities (creatine kinase, its MB-izoenzyme, lactate dehydrogenase, hydroxybutyrate dehydrogenase) are currently used for the detection of acute myocardial infarction and for the further monitoring of the patient and managing his therapy. In the past decade, many cardiospecific biochemical markers were discovered and gradually introduced into the routine clinical practice. The most perspective markers are some molecules of contractile proteins of heart myofibrils (troponins, myosin chains) as well as "rediscovered" myoglobin. The aim of this review article is to inform about the commonly used, as well as about the new biochemical markers, to discuss some problems of diagnostic strategy in the early and exact detection of ischemic myocardial damage and to attract attention to the difficulties. However its disadvantage resides in its presence in both myocardium and skeletal muscles which arise when the diagnosis of acute myocardial infarction is prematurely excluded from consideration and such patients are discharged too soon from hospital. (Fig. 1, Tab. 1, Ref. 72.) 相似文献
914.
LI al-Gazali AH Dawodu M Hamada M Bakir D Bakalinová 《Canadian Metallurgical Quarterly》1996,63(2):346-347
We report on a child with severe midline facial cleft, bilateral cleft lip and palate, telecanthus, S-shaped palpebral fissures, limbic dermoid, midface hypoplasia, hypoplastic corpus callosum, and multiple skin appendages. This case may be an example of severe frontofacionasal "dysplasia" or a newly recognised syndrome. 相似文献
915.
G Gulyás 《Canadian Metallurgical Quarterly》1996,20(5):369-375
Two female and three male patients with acquired "tufted angioma" are presented. The age of these patients ranged from 10 to 62 years. Two lesions were sited in the head and neck region, two in the upper extremities, and one on the trunk. Clinically, the angiomatous lesions appeared as elevated plaques, flat lesions with papular and macular areas, or erythematous plaques with small nodules. In four cases a biopsy was done, and in one case the tumour was excised. Histologically, the neoplasms were characterized by irregularly distributed vascular tufts in the dermis, and, in one case, in the upper subcutis. The vascular tufts were composed of plump endothelial cells and spindle-shaped pericytes surrounded by crescent-shaped vascular spaces. The positive staining for CD 31 and for CD 34 and alpha-smooth muscle actin, and the negative staining of endothelial cells for factor VIII underline both the existence of two cellular components in tufted angioma and the immaturity of endothelial cells. Evidence of regular mitotic figures in two cases and increased proliferative activity in three out of four cases tested, emphasize the neoplastic nature of slowly growing tufted angioma. Benign tufted angioma is a distinct entity in the spectrum of capillary haemangiomas and must be distinguished from other vascular neoplasms. 相似文献
916.
E Poves Martínez 《Canadian Metallurgical Quarterly》1996,88(10):677-686
In the last years different classification systems for hospitalized patients have been developed in the United States, that allow to evaluate different aspects of any Hospital: The quality, the efficacy and the efficiency. The classification of "The Diagnosis Related Groups" (DRG) relates the hospitalized patients with the expenses that they generate, and it is the most used in Europe. In the version DRG-All Patient, all the diagnoses and procedures of the hospitalized patients, using the International Classification of Diseases, are divided in to 25 Major Diagnostic Categories (MDC) where each one excludes all the others. We describe the behavior with respect to the age, sex and stay of all the GDR integrated in the CDM 6 and 7: diseases and disorders of the digestive tract, and diseases and disorders of the hepatobiliary system and the pancreas. The study has been carried out with a national data base of two millions of cases seen from 214 acute-care Hospitals. The MDC number 6 is the most frequent, with an important number of patients in the pediatric age; it is more frequent in males; the average stay is 8.59 days and 19 GDR (36.5%) have a variation coefficient greater than one. The other MDC, number 7 is less frequent, the majority of the patients are between 60-80 years of age, the average stay is 12.2 days with a coefficient of variation greater than one in 4 GDR (17.4%). Clinical Services should know the characteristics and behavior of their patients, as well as the comparison with the national data bases. This may allow a control of the quality and the costs by using a common "language" with the managers. 相似文献
917.
The effect of the removal of pineal gland, performed in adult age or during perinatal life, was investigated in the neonatal androgen sterility (NA-CEA) syndrome, in combination with drugs acting on serotonergic neurons. Perinatal pinealectomy (Px) was more potent in preventing the development of NA-CEA state than Px performed in the adult age. These data indicate that the masculinized hypothalamus becomes less sensitive to pineal influences during the lifespan. Effect of Px was potentiated by drugs increasing the central serotonergic tone. The results lead to the assumption that pineal hormones are influential on the maturation of serotonergic neurons, which might interfere with the sterilizing property of neonatal androgen treatment during the "critical" period of sexual differentiation. 相似文献
918.
Monoclonal antibodies (MoAbs) against potato virus A (PVA) were examined in their reactivity with PVA and its denatured capsid protein (PVA-CP) bound to the nitrocellulose membrane. Five MoAbs reacted with native PVA, three of them also with PVA-CP. One MoAb gave no reaction in dot-blot test. In polyacrylamide electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) PVA-CP migrated as two major bands. In immunoblot analysis, two MoAbs reacted only with the slower band, one only with the faster one. We presume that those bands do not correspond to the intact CP but they do to truncated N- and C-terminal CP molecules, respectively, and that the corresponding epitopes reacting with MoAbs are localized near to both termini of CP molecules. After mild trypsinolysis of PVA particles no MoAb reacted with resulting "core" CP. 相似文献
919.
D Defey E Storch S Cardozo O Díaz G Fernández 《Canadian Metallurgical Quarterly》1996,42(10):1447-1456
Menopause has often been described as a time of loss and decay in the lay and medical literature. The present research aims at defining women's perception of themselves and their health care needs in this period of life. Through a community-based sample of women, participative assessments were performed and their conclusions contrasted with the opinions of male and female gynecologists. Though both groups coincided concerning the relevance of loneliness, partnership, beauty and the "empty nest" syndrome, several items showed a marked difference between both groups. Gynecologists tended to perceive women as much more striving for an active sex-life, depressed, lacking projects for the future and worried about their health care than they actually were. Women, instead, stressed the relevance of menopause as a life crisis laden with opportunities for self-accomplishment and positive changes in life-style towards greater autonomy. 相似文献
920.
David A. Bader Joseph Jájá David Harwood Larry S. Davis 《The Journal of supercomputing》1996,10(2):141-168
This paper presents efficient and portable implementations of a powerful image enhancement process, the Symmetric Neighborhood Filter (SNF), and an image segmentation technique that makes use of the SNF and a variant of the conventional connected components algorithm which we call -Connected Components. We use efficient techniques for distributing and coalescing data as well as efficient combinations of task and data parallelism. The image segmentation algorithm makes use of an efficient connected components algorithm based on a novel approach for parallel merging. The algorithms have been coded in Split-C and run on a variety of platforms, including the Thinking Machines CM-5, IBM SP-1 and SP-2, Cray Research T3D, Meiko Scientific CS-2, Intel Paragon, and workstation clusters. Our experimental results are consistent with the theoretical analysis (and provide the best known execution times for segmentation, even when compared with machine-specific implementations). Our test data include difficult images from the Landsat Thematic Mapper (TM) satellite data.Also affiliated with the Department of Electrical Engineering.Also affiliated with the Department of Computer Science and the Center for Automation Research. 相似文献