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81.
FC Blow KL Barry BJ BootsMiller LA Copeland R McCormick S Visnic 《Canadian Metallurgical Quarterly》1998,32(5):311-319
Within a fungal species, a subset of individuals may have more than the minimal complement of chromosomes. If the extra chromosomes are composed primarily of DNA not found in all representatives of the species, they are most appropriately referred to as supernumerary chromosomes. The patterns of repeated DNA sequences on certain supernumerary chromosomes suggest that they have a different evolutionary history from the essential chromosomes in the same genome. Supernumerary chromosomes can carry functional genes and, in at least two fungal species, genes on such chromosomes play important roles in host-pathogen interactions. Supernumerary chromosomes that confer an adaptive advantage in certain habitats, such as the ability to cause disease on a specific host, may be referred to as "conditionally dispensable" chromosomes in order to reflect their importance in some, but not all, growth conditions. In addition to describing the structural and functional characteristics of known supernumerary chromosomes in fungi, this review discusses the relative merits of the terms that have been used to describe them, and establishes experimental criteria for their identification. 相似文献
82.
The influence of the quality of care that patients receive during the course of their illness has been the subject of special scrutiny in the area of mental health. The concept of "expressed emotion" (EE) evolved in an effort to understand the impact of family and social environment on the vulnerability to relapse of schizophrenic patients. A semistructured interview, the Camberwell Family Interview, was developed to assess expressed emotion. This article examines the historical context, generalizability, methodological strengths and limitations of the construct of EE and the Camberwell Family Interview, as well as the nature and effects of treatment intervention programs designed to neutralize adverse effects of patient caretaker attitudes. 相似文献
83.
84.
HW Klafki AI Pick I Pardowitz T Cole LA Awni HU Barnikol F Mayer HD Kratzin N Hilschmann 《Canadian Metallurgical Quarterly》1993,374(12):1117-1122
Motivated by the finding that the amino acid sequence of the Bence Jones protein BJP-DIA was identical to that of the main protein component of the amyloid fibrils obtained from the same patient with AL-amyloidosis, (Klafki, H.-W., Kratzin, H.-D., Pick, A.-I., Eckart, K., Karas, M. & Hilschmann, N. (1992) Biochemistry 31, 3265-3272.), we attempted to create "amyloid-like" fibrils from the Bence Jones protein in vitro, without addition of proteolytic enzymes. Reduction of BJP-DIA, solubilized in PBS, pH 7.4, overnight at 37 degrees C resulted in the formation of a precipitate which had affinity for the dye Congo red. Electron microscopy of negatively stained samples of the reduced protein revealed aggregates of linear unbranched fibrils. SDS-polyacrylamide gel electrophoresis demonstrated that the precipitate consisted almost exclusively of intact light chain molecules. This result makes it possible to deduce a molecular model of these amyloid fibrils generated in vitro. 相似文献
85.
86.
Juan J. Cárdenas Luis RomeralAntonio Garcia Fabio Andrade 《Expert systems with applications》2012,39(5):5557-5565
This work presents an electricity consumption-forecasting framework configured automatically and based on an Adaptative Neural Network Inference System (ANFIS). This framework is aimed to be implemented in industrial plants, such as automotive factories, with the objective of giving support to an Intelligent Energy Management System (IEMS). The forecasting purpose is to support the decision-making (i.e. scheduling workdays, on-off production lines, shift power loads to avoid load peaks, etc.) to optimize and improve economical, environmental and electrical key performance indicators. The base structure algorithm, the ANFIS algorithm, was configured by means of a Multi Objective Genetic Algorithm (MOGA), with the aim of getting an automatic-configuration system modelling. This system was implemented in an independent section of an automotive factory, which was selected for the high randomness of its main loads. The time resolution for forecasting was the quarter hour. Under these challenging conditions, the autonomous configuration, system learning and prognosis were tested with success. 相似文献
87.
Inhibition of HeLa cell messenger RNA translation by 7-methylguanosine 5'-monophosphate 总被引:2,自引:0,他引:2
LA Weber ER Feman ED Hickey MC Williams C Baglioni 《Canadian Metallurgical Quarterly》1976,251(18):5657-5662
Translation of HeLa cell RNA containing poly(A) in a wheat germ cell-free system is markedly but incompletely inhibited by 7-methylguanosine 5'-monophosphate (m7G5'p). We have analyzed the translation products synthesized in the presence of different concentrations of m7G5'p and find that translation of all mRNAs is equally inhibited. To demonstrate the specificity of the inhibitor for RNAs with 5'-terminal m7G5' ppp... we show that specific translation products of satellite tobacco necrosis virus RNA, which does not have this 5' terminus, are synthesized in the presence of m7G5' p. Protein synthesis programmed by endogenous mRNA in a HeLa cell-free system is inhibited after a 10-min lag by m7G5' p. Other guanosine nucleotides without the 7-methyl group or with the phosphate in a different position are not inhibitor. We show that translation of all mRNAs is inhibited to a similar extent by m7G5'p in the HeLa cell-free system, by synthesizing 35S-labeled proteins in the presence of different inhibitory concentrations of this nucleotide and analyzing the translation products by electrophoresis and autoradiography. Translation of encephalomyocarditis virus RNA added to the HeLa cell-free system is not inhibited by m7"g5p; this viral RNA does not have this nucleotide at the 5' terminus. This indicates that m7G5'p specifically inhibits translation of mRNAs with the 5' terminus m7G5'ppp... and suggests that initiation of translation of picornavirus RNA may proceed via a mechanism different from that of cellular mRNAs. 相似文献
88.
The smoking habits of 56 families who lost babies to the sudden infant death syndrome (SIDS) were compared to those of 86 control families. A higher proportion of SIDS mothers smoked both during pregnancy (61% vs. 42%) and after their babies were born (59% vs. 37%). SIDS mother also smoked a significantly greater number of cigarettes than controls. Exposure to cigarette smoke ("passive smoking") appears to enhance the risk of SIDS for reasons not known. 相似文献
89.
Because of the unresolved controversy regarding the effect of epidural anesthesia upon uterine contractility, it was decided to study its effect on a small number of patients. Intrauterine and intra-arterial continuous pressure, continuous fetal heart rate, and maternal heart rate recordings were obtained from at least 20 minutes before administration of the epidural anesthic until complete dilatation in these patients. Nineteen patients were in spontaneous labor, and 18 had labor stimulated with oxytocin. Plain lidocaine, 1 or 1.5%, was used in 12 patients (30 observations), and lidocaine with epinephrine, 1:200,000 was used in 26 patients (51 observations). Uterine contractions were calculated in Montevideo units for 60 minutes following the epidural anesthetic. The changes, if any, were compared in both groups. There was a significant decrease in uterine activity when epinephrine was added to the anesthetic solution, mainly a lessening of intensity. There were comparable decreases in systolic/diastolic blood pressure in both groups and compensatory tachycardia. In one case, severe hypertension was observed following administration of lidocaine epinephrine. It was concluded that the addition of epinephrine to the anesthetic solution predictably produces diminution of uterine activity, and it does not give "cardiovascular support" to the laboring patient. 相似文献
90.
VA Belitser TV Varetskaia SN Tsynkalovskaia LA Tsariuk LI Shevchenko 《Canadian Metallurgical Quarterly》1976,48(4):521-532
A new diagnostic method to determine fibrinogen and fibrin splitting products is based on the fact that high-molecular fragments acting as specific inhibitors of fibrin self-assembly compose these products. Fibrinogen and fibrin splitting products are detected and determined quantitatively by prolongation of coagulation time in the test with the standard monomeric fibrin. The number of units of anticoagulating activity in the studied urine are the results of the determinations. Sensitivity of the method if necessary may be increased by adding of a certain amount of the fibrinogen and fibrin splitting products to the test that makes a favourable background for the action of the products. The method is rather sensitive, reliable and simple. It may be used in ordinary clinical laboratories. The method proved to be quite satisfactory when testing renal diseases at the clinic. It is of great significance for early detection of the transplanted kidney rejection. The new method is compared with the known immunological method which consist in determination of the inhibitory effect of the fibrinogen and fibrin splitting products on agglutination of erythrocytes of specific antibodies; the erythrocytes being subjected to "tanning" and "loading" with fibrinogen. A satisfactory correlation is found between the results of two methods. 相似文献