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1.
1IntroductionElbo(ECG)offersalotofilllcorralltinfondionforthediagnosisOfheartdis-eases.Berz1,seahaormalEChcax[lrins>llleu"knownsituations,thcycanbeCSUghtinthelongti1Ylecontin~11xHlltoriDg.ndterrnoultonngsystemwhichcanrecord24-hoUrECGdataisoneofeffectiveme~toprovidethefun~.AlthOUghthehag6scaleICmorestohavebeeddevelopepbedeavailabletostorelOngtboeECGdsta,itisveqdifficultyandtioublesomethatalopnUmbeOfdstaisprasersandstoredortiallsillltted.InthedigitedECGdata,thereare… 相似文献
2.
C. VILLARREAL M. H. RODRIGUEZ D. N. BOWN J. I. ARREDONDO-JIMÉNEZ 《Medical and veterinary entomology》1995,9(2):187-194
Abstract. Village-scale trials were carried out in southern Mexico to compare the efficacy of indoor-spraying of the pyrethroid insecticide lambda-cyhalothrin applied either as low-volume (LV) aqueous emulsion or as wettable-powder (WP) aqueous suspension for residual control of the principal coastal malaria vector Anopheles albimanus. Three indoor spray rounds were conducted at 3-month intervals using back-pack mist-blowers to apply lambda-cyhalothrin 12.5 mg a.i./m2 by LV, whereas the WP was applied by conventional compression sprayer at a mean rate of 26.5 mg a.i./m2 .
Both treatments caused mosquito mortality indoors and outdoors (collected inside house curtains) as a result of contact with treated surfaces before and after feeding, but had no significant impact on overall population density of An. albimanus resting indoors or assessed by human bait collections. Contact bioassays showed that WP and LV treatments with lambda-cyhalothrin were effective for 12–20 weeks (>75% mortality) without causing excito-repellency.
Compared to the WP treatment (8 houses/man/day), LV treatment (25 houses/man/day) was more than 3 times quicker per house, potentially saving 68% of labour costs. This is offset, however, by the much lower unit price of a compression sprayer (e.g. Hudson 'X-pert' at US120) than a mist-blower (e.g. 'Super Jolly' at US350), and higher running costs for LV applications. It was calculated, therefore, that LV becomes more economical than WP after 18.8 treatments/100 houses/10 men at equivalent rates of application, or after 7.6 spray rounds with half-rate LV applications. 相似文献
Both treatments caused mosquito mortality indoors and outdoors (collected inside house curtains) as a result of contact with treated surfaces before and after feeding, but had no significant impact on overall population density of An. albimanus resting indoors or assessed by human bait collections. Contact bioassays showed that WP and LV treatments with lambda-cyhalothrin were effective for 12–20 weeks (>75% mortality) without causing excito-repellency.
Compared to the WP treatment (8 houses/man/day), LV treatment (25 houses/man/day) was more than 3 times quicker per house, potentially saving 68% of labour costs. This is offset, however, by the much lower unit price of a compression sprayer (e.g. Hudson 'X-pert' at US120) than a mist-blower (e.g. 'Super Jolly' at US350), and higher running costs for LV applications. It was calculated, therefore, that LV becomes more economical than WP after 18.8 treatments/100 houses/10 men at equivalent rates of application, or after 7.6 spray rounds with half-rate LV applications. 相似文献
3.
María Prados-Privado Juan Carlos Prados-Frutos José Luis Calvo-Guirado José Antonio Bea 《Computer methods in biomechanics and biomedical engineering》2016,19(15):1583-1591
To measure fatigue in dental implants and in its components, it is necessary to use a probabilistic analysis since the randomness in the output depends on a number of parameters (such as fatigue properties of titanium and applied loads, unknown beforehand as they depend on mastication habits). The purpose is to apply a probabilistic approximation in order to predict fatigue life, taking into account the randomness of variables. More accuracy on the results has been obtained by taking into account different load blocks with different amplitudes, as happens with bite forces during the day and allowing us to know how effects have different type of bruxism on the piece analysed. 相似文献
4.
H. Daniel 《Biological trace element research》1987,13(1):301-318
Because of the large μ mass compared to the electron mass, the muonic X-rays have energies very suitable for standard γ-ray
spectroscopy (Ge detectors), so every element is easily recognized. By selecting the primary μ energies appropriately any
part of the specimen, also well inside, can be nondestructively investigated. On the other hand, surface layers may be analyzed.
Accuracies of quantitative analyses are 1% of the atomic abundance of the element in question in favorite cases. Results on
applications in nuclear medicine and surface physics are presented, and ways of improving the muon flux density are discussed. 相似文献
5.
Summary In the pelagic larvacean Oikopleura dioica, the epithelium lining the alimentary tract consists of ciliated and unciliated cell types. The ciliated cells also exhibit an apical border of long microvilli. Between the microvilli, the cellular membrane often projects deeply down into the cytoplasm; the membranes of these invaginations and those of apicolateral interdigitations may be associated with one another by tight junctions. Some of these junctions may be autocellular. The tight junctions are seen by freeze-fracture to be very simple in construction, composed of a single row of intramembranous particles, which may be fused into a P-face ridge. There is a dense cytoplasmic fuzz associated with these tight junctions which may extend into adjoining zonula adhaerens-like regions. The invaginations of the apical membranes are, in addition, associated by gap junctions which may also be autocellular. More conventional homocellular and heterocellular tight and gap junctions occur along the lateral borders of ciliated cells and between ciliated and unciliated cells. These gap junctions possess a reduced intercellular cleft and typical P-face connexons arranged in macular plaques, with complementary E-face pits. Both cell types exhibit extensive stacks of basal and lateral interdigitations. The tight junctions found here are unusual in that they are associated with a dense cytoplasmic fuzz which is normally more characteristic of zonulae adhaerentes. 相似文献
6.
STEVANJ. ARNOLD ALBERT F. BENNETT 《Biological journal of the Linnean Society. Linnean Society of London》1988,34(2):175-190
A series of morphologieal and locomotor performance variables was measured in a population of newborn garter snakes to determine whether performance capacity has a significant morphological basis in these animals. Morphological traits measured were body length and mass, number of body and tail vertebrae and numbers of vertebral abnormalities. Locomotor performances included burst and mid-distance speed and distance and time crawled before anti-predator displays were assumed. All performance variables were repeatable in daily replicate trials ( P < 0.001). Individual burst speed, mid-distance speed, and distance crawled were significantly correlated pairwise ( P < 0.01). Most morphological and performance variables had a significant mass dependence (static allometry), although the effects were rather weak ( r 2 < 0.1, except for body length): larger animals performed better and had fewer abnormalities. There were significant associations between some morphological traits and locomotor performance. Morphological factors accounted for 19% of the variation in mid-distance speed and 14% of the variation in antipredator behavior by multiple regression analysis. Canonical correlation of all performance and morphological variables simultaneously accounted for 24% of the observed variation in performance. Numbers of body and tail vertebrae (assayed by scale counts) had an interactive effect on speed of locomotion. 相似文献
7.
Summary Factors affecting the polyethylene glycol (PEG)-induced membrane fusion were examined. Human erythrocyte membrane ghosts, cytoskeleton-free vesicles budded from erythrocytes, mechanically disrupted erythrocyte vesicles, and recombinant vesicles from glycophorin and egg phosphatidylcholine were used as models. Fusion was monitored by darkfield light microscopy and by freeze-fracture electron microscopy. Osmotic swelling was found necessary for fusion between membrane ghosts following PEG treatment. The sample with the highest fusion percentage was sealed ghosts incubated in hypotonic media after at least 5 min of treatment in <25% PEG. At similar osmolarity, glycerol, dextran and PEG produced progressively more pronounced intramembranous particle (IMP) patching, correlating with their increasing fusion percentages. The patching of IMP preceded cell-cell contact, and occurred without direct PEG-protein interaction. The presence of cytoskeletal elements in small vesicles had no significant effect on fusion, nor on the aggregation of intramembranous particle (IMP) upon PEG treatment. Disrupting the membrane by lysolecithin, dimethylsulfoxide, retinol or mild sonication resulted in the fragmentation of ghosts without an increase in fusion percentage. The purity of the commercial PEG used had no apparent effect on fusion. We concluded that the key steps in PEG-induced fusion of cell membrane are the creation of IMP-free zones, and the osmotic swelling of cells after the formation of bilayer contacts during the PEG treatment. Cell cytoskeleton affects PEG-induced fusion only to the extent of affecting IMP patching. 相似文献
8.
George M. White 《Cell biochemistry and biophysics》1987,11(1):25-33
Computers, the human mind, and social systems have common problems of inadequate memory and insufficient data manipulation
speed. In each of these domains, information compression techniques have evolved to reduce storage and processing needs. Among
the techniques for information compression, coding of information in procedures stands out as exceptionally powerful. Procedural
information coding also gives rise to behavior that may be defined as intelligent. It is found in the human mind, in machines
and in social systems. Its use in human thought is aided by language development which promotes regular review of abstract
procedures. A practical consequence of better understanding of procedural information coding is the possibility of training
people to exhibit greater mental capacity, a controversial possibility. This paper explores the impact of data processing
resource limitations, data compression and procedural thinking in men and machines. 相似文献
9.
Summary Cell junctions in the renal tubule of the fresh-water rainbow trout were studied with thin-section and freeze-fracture techniques. Gap junctions were restricted to the proximal tubule, which is consistent with other vertebrate classes. Segments I and II of the proximal tubule and the collecting tubule/collecting duct system exhibited a well-developed zonula occludens with anastomosing strands. The distal segment showed a narrow zonula occludens composed of few parallel strands. The structure of the occluding junctions along the renal tubule of this teleost displays several similarities with the pattern of the zonulae occludentes in the amphibian and the mammalian nephron. From these observations, in conjunction with available data from other vertebrate classes, it can be concluded that in the proximal tubule the development of a deep and complex zonula occludens is a general feature of cold-blooded vertebrates. 相似文献
10.
(1) Using asolectin (mixed soybean phospholipids) liposomes, extra lipid, with or without additional plastoquinone, has been introduced into isolated thylakoid membranes of pea chloroplasts. (2) Evidence for this lipid enrichment was obtained from freeze-fracture which indicated that a decrease in the numbers of EF and PF particles per unit area of membrane occurred with increasing lipid incorporation. The decrease was not due to loss of integral membrane polypeptides as judged by assay of cytochrome present or SDS-polyacrylamide gel electrophoresis of lipid-enriched membrane fractions. Moreover, the enrichment procedure did not lead to extraction of low molecular weight lipophilic membrane components or of thylakoid membrane lipids. (3) The introduction of phospholipids into the membrane affected steady-state electron transport. Inhibition of electron transport was observed when either water (Photosystem (PS) II + PS I) or duroquinol (PS I) was used as electron donor with methyl viologen as electron acceptor, and the degree of inhibition increased with higher enrichment levels. Introduction of exogenous plastoquinone with the additional lipid had little effect on whole-chain electron transport, but caused an increase in the 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB)-sensitive rate of PS I electron transport. The inhibition was also detected by flash-induced oxidation-reduction changes of cytochrome f. 相似文献