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961.
HS Subramanya K Gopinath MV Nayudu HS Savithri MR Murthy 《Canadian Metallurgical Quarterly》1993,229(1):20-25
Serum IgG subclasses and Serum IgA were studied in 43 infants with acute bronchiolitis and 20 healthy infants. IgG subclasses were determined by a capture ELISA and IgA was quantified by turbidimetry. IgG1 concentrations were significantly lower in infants with bronchiolitis than in normal infants. The other IgG subclasses and IgA did not differ between the groups. The subgroups of infants with bronchiolitis who had previously suffered from otitis media or bronchitis, had significantly lower IgG2 than the other infants with bronchiolitis. The same was found for infants with bronchiolitis who had suffered from three or more lower respiratory tract infections. In infants who had suffered from upper or lower respiratory infections before the acute bronchiolitis, IgA was significantly higher than in infants without previous respiratory infections. Ten infants with bronchiolitis (23%) had IgG1 deficiency, that is values below the lower reference limit calculated in a population of healthy Norwegian infants. No healthy infants had any IgG1 deficiency. No infant with bronchiolitis had IgG2 or IgG3 deficiency. The low IgG1 values found in infants with acute bronchiolitis, may be one cause for infants to be more susceptible to RS virus infections. 相似文献
962.
P Estébanez M Rua-Figueroa MD Aguilar F Bru MV Rog Emilio Zunzunegui 《Canadian Metallurgical Quarterly》1996,10(4):445-446
Live eosinophils when mixed with Acridine Orange solution and viewed microscopically using u.v. light show very intense colours of their granules (yellow, orange and red) and green nuclear staining. Their active movement, translocation of granules and degranulation can be observed in vitro. Using this method, live eosinophils can be easily differentiated and enumerated. 相似文献
963.
964.
EB Trexler MV Bennett TA Bargiello VK Verselis 《Canadian Metallurgical Quarterly》1996,93(12):5836-5841
Gap junction channels are formed by members of the connexin gene family and mediate direct intercellular communication through linked hemichannels (connexons) from each of two adjacent cells. While for most connexins, the hemichannels appear to require an apposing hemichannel to open, macroscopic currents obtained from Xenopus oocytes expressing rat Cx46 suggested that some hemichannels can be readily opened by membrane depolarization [Paul, D. L., Ebihara, L., Takemoto, L. J., Swenson, K. I. & Goodenough, D. A. (1991), J. Cell Biol. 115, 1077-1089]. Here we demonstrate by single channel recording that hemichannels comprised of rat Cx46 exhibit complex voltage gating consistent with there being two distinct gating mechanisms. One mechanism partially closes Cx46 hemichannels from a fully open state, gammaopen, to a substate, gammasub, about one-third of the conductance of gammaopen; these transitions occur when the cell is depolarized to inside positive voltages, consistent with gating by transjunctional voltage in Cx46 gap junctions. The other gating mechanism closes Cx46 hemichannels to a fully closed state, gammaclosed, on hyperpolarization to inside negative voltages and has unusual characteristics; transitions between gammaclosed and gammaopen appear slow (10-20 ms), often involving several transient substates distinct from gammasub. The polarity of activation and kinetics of this latter form of gating indicate that it is the mechanism by which these hemichannels open in the cell surface membrane when unapposed by another hemichannel. Cx46 hemichannels display a substantial preference for cations over anions, yet have a large unitary conductance (approximately 300 pS) and a relatively large pore as inferred from permeability to tetraethylammonium (approximately 8.5 angstroms diameter). These hemichannels open at physiological voltages and could induce substantial cation fluxes in cells expressing Cx46. 相似文献
965.
MV Nakariakova TA Antonenko TG Khomutova MG Massova TK Konstantinova EG Gershte?n 《Canadian Metallurgical Quarterly》1996,(3):15-17
Inhaled Orlok causes changes in the CNS, blood morphology, renal function. The threshold concentration of Orlok is 0.17 mg/m3, its subthreshold concentration is 0.023 mg/m3, MAC in the workplace air is 0.05 mg/m3. 相似文献
966.
967.
Perceiving the length of a rod by dynamic touch is tied to the inertia tensor Iij, a quantification of its resistance to rotational acceleration. Perception of the portion extending in front of the grasp has previously been ascribed to decomposing one component of Iij by attention. The tensorial nature of dynamic touch suggests that this ability must be anchored wholly in the tensor. Three experiments show that perceived partial length is a function of two components of the tensor, one tied primarily to magnitude and the other tied primarily to direction, whereas perceived whole length is a function of a magnitude component alone. Dynamic touch is characterized in terms of a haptic perceptual instrument that softly assembles to exploit Iij differently depending on the intention, producing 1:1 maps that are appropriately scaled for each intention. 相似文献
968.
969.
970.
EG Pedachenko MV Khizhniak TI Makeeva AF Tanase?chum OV Tolstikhin 《Canadian Metallurgical Quarterly》1998,97(6):14-16
How many times have you been asked to participate in a meeting, forum, or task force to address a community health issue in the last few years? Opportunities seem to crop up almost weekly as non-profit organizations acclimate to meet changing needs and health systems continue to adapt to market forces. But participating in ongoing community projects, or even attending periodic meetings, draws time away from practice and professional obligations and limits an already modest supply of personal time. Is involvement in a community collaborative effort worth the time? And, if so, what are the benefits and challenges to physicians, health systems, and communities from this type of investment? 相似文献