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81.
Differing levels of the Ca(2+)-ATPase enzymes that reside on the plasma membrane (PM) and on the endoplasmic reticulum (ER) were identified in individual rat cochlear tissues by the use of a semi-quantitative enzyme-linked immunosorbent assay (ELISA). Unlike other studies, a specific antibody to PM Ca(2+)-ATPase was used to detect significantly greater levels (about 2x) of PM Ca(2+)-ATPase in the stria vascularis (SV) than that in the spiral ligament (SL) and organ of Corti (OC) tissues. Similarly, levels of ER Ca(2+)-ATPase were also significantly higher in the SV than in the SL and OC tissues. The presence of ER Ca(2+)-ATPase in the tissues of the SV has not been demonstrated previously. Given the importance of Ca2+ homeostasis in the inner ear, the statistically significantly higher densities of both PM and ER Ca(2+)-ATPase measured in the SV relative to the SL and OC regions would indicate tissue-specific responses to fluctuations in systemic and local Ca2+ concentrations. 相似文献
82.
A telephone survey was conducted of all the 71 Danish hospitals with the capacity to receive acutely ill medical patients. The purpose was to register treatment regimes used in acute asthma and exacerbations in chronic obstructive pulmonary disease (COPD). The house officer on duty was interviewed and questioned about the use of nebulizers, oxygen therapy, bronchodilators, steroids, theophyllins and monitoring of the patient's condition. The physician survey was supplemented by a smaller survey among emergency room nurses about nebulizing systems. The answers showed inadequate knowledge of nebulizing systems. There was a noticeable variation in the dosing of oxygen and in the dosing of bronchodilators and steroids. beta 2-agonist treatment by nebulizer differed with a factor 14 in dose. The majority of the physicians had no specific parameters for monitoring severity of disease. CONCLUSION: There is a need for improvement of the knowledge of nebulizing systems, including specific knowledge of the appropriate use of propellant gasflow and time of nebulizing for optimum performance of the used nebulizer. Divergent answers from the nurses and the physicians show the need for interdisciplinary instruction. The noticeable variation in treatment in this Danish survey displays a need for quality control in terms of concise guidelines for medical therapy in acute exacerbations of asthma and COPD and guidelines for monitoring of the response to the treatment. A suggestion for a treatment regime is proposed. 相似文献
83.
K Kasai E Kanazawa H Aboshi LC Richards M Matsuno 《Canadian Metallurgical Quarterly》1997,39(4):196-201
The purpose of this study was to provide information about arch shape variations among South Pacific populations. The application of Fourier transforms, Y(phi i) = ao/2 + sigma (aicos phi i + bisin phi i) was used to separate two components of variation; size and shape. Dental arch size can be described by one coefficient (ao), while the shape can be summarized by the first three harmonics (amp1-3) in the Fourier series. The materials used in this study were dental casts of South Pacific populations (Fiji, Western Samoa and Kiribati), Australian Aboriginals and Japanese. Fijians, Western Samoans and Kiribati people have larger upper and lower dental arches than that of Japanese. These populations were separated by the arch size and first Fourier amplitudes which showed the arch depth/width ratio. The Fijian upper and lower dental arches were significantly larger than those found in other populations and was characterized by a wide posterior arch breadth. The Western Samoan and Kiribati arch shape was more similar to the Japanese arch shape than the Fijian. Distribution patterns of arch shape characteristics in these populations showed the same tendencies in the upper and lower arches. 相似文献
84.
Courts routinely award coverage for TMJ disorders under medical plans, despite exclusionary language and evidence that the insured failed to disclose preexisting treatment as required by the plan and neglected to attempt more conservative treatment first. Such decisions adversely affect both the health carrier and the plan participants. Various states have enacted legislation mandating coverage of TMJ; however, TMJ issues still exist and will remain a frequent topic for litigation until the judiciary recognizes that validating contract language ultimately benefits insureds as consumers and reinforces the integrity of the industry as a whole. 相似文献
85.
86.
B Coyle W Reardon JA Herbrick LC Tsui E Gausden J Lee R Coffey A Grueters A Grossman PD Phelps L Luxon P Kendall-Taylor SW Scherer RC Trembath 《Canadian Metallurgical Quarterly》1998,7(7):1105-1112
Pendred syndrome is an autosomal recessive disorder characterized by the association between sensorineural hearing loss and thyroid swelling or goitre and is likely to be the most common form of syndromic deafness. Within the thyroid gland of affected individuals, iodide is incompletely organified with variable effects upon thyroid hormone biosynthesis, whilst the molecular basis of the hearing loss is unknown. The PDS gene has been identified by positional cloning of chromosome 7q31, within the Pendred syndrome critical linkage interval and encodes for a putative ion transporter called pendrin. We have investigated a cohort of 56 kindreds, all with features suggestive of a diagnosis of Pendred syndrome. Molecular analysis of the PDS gene identified 47 of the 60 (78%) mutant alleles in 31 families (includes three homozygous consanguineous kindreds and one extended family segregating three mutant alleles). Moreover, four recurrent mutations accounted for 35 (74%) of PDS disease chromosomes detected and haplotype analysis would favour common founders rather than mutational hotspots within the PDS gene. Whilst these findings demonstrate molecular heterogeneity for PDS mutations associated with Pendred syndrome, this study would support the use of molecular analysis of the PDS gene in the assessment of families with congenital hearing loss. 相似文献
87.
Fas (CD95) and Fas ligand (FasL) play major roles in staphylococcal enterotoxin B (SEB)-induced peripheral deletion of Vbeta8+ T cells. We found that peripheral deletion was defective in radiation chimeras with non-functional tissue FasL, regardless of the FasL status of the bone marrow-derived cells. SEB induced a dramatic upregulation of FasL expression and function in nonlymphoid cells of liver and small intestine. This effect was resistant to inhibition by cyclosporin A, which also failed to inhibit peripheral deletion. In SCID animals nonlymphoid tissues did not express FasL in response to SEB unless transplanted lymphocytes were present. Thus, some immune responses induce FasL in nonlymphoid tissues, which in turn kills activated lymphocytes, leading to peripheral T cell deletion. 相似文献
88.
89.
JD Fisch BH Ortiz SI Tazuke U Chitkara LC Giudice 《Canadian Metallurgical Quarterly》1998,13(7):1981-1986
Recent reports describe successful treatment of interstitial ectopic pregnancies using methotrexate. While the number of reported cases is increasing, no consensus exists regarding the management of this complication of pregnancy. We present the successful use of combined systemic and direct intrasac injection of methotrexate for an interstitial pregnancy with the highest yet reported initial beta-human chorionic gonadotrophin concentration (102,000 mIU/ml). We also describe the use of Doppler ultrasound for monitoring treatment progression. Through a review of the current literature, we propose to facilitate management decisions and increase outcome success by summarizing previously reported treatment regimens and by describing enhanced parameters for patient selection and monitoring. 相似文献
90.
R Trotta KA Puorro M Paroli L Azzoni B Abebe LC Eisenlohr B Perussia 《Canadian Metallurgical Quarterly》1998,161(12):6648-6656
Extracellular signal-regulated kinases (ERK, also known as mitogen-activated protein kinases) are serine-threonine kinases transducing signals elicited upon ligand binding to several tyrosine kinase-associated receptors. We have reported that ERK2 phosphorylation and activation follows engagement of the low affinity receptor for the Fc portion of IgG (CD16) on NK cells, and is necessary for CD16-induced TNF-alpha mRNA expression. Here, we analyzed the involvement of ERK in NK cell-mediated cytotoxicity and IFN-gamma expression induced upon stimulation with targets cells, coated or not with Abs. Our data indicate that, as with immune complexes, ERK2 phosphorylation occurs in human primary NK cells upon interaction with target cells sensitive to granule exocytosis-mediated spontaneous cytotoxicity, and that this regulates both target cell- and immune complex-induced cytotoxicity and IFN-gamma mRNA expression. A specific inhibitor of mitogen-activated protein kinase kinase reduced both spontaneous and Ab-dependent cytotoxicity in a dose-dependent manner involving, at least in part, inhibition of granule exocytosis without affecting effector/target cell interaction and rearrangement of the cytoskeleton proteins actin and tubulin. Involvement of ERK in the regulation of Ca2+-dependent cell-mediated cytotoxicity was confirmed, using a genetic approach, in primary NK cells infected with a recombinant vaccinia virus encoding an ERK inactive mutant. These data indicate that the biochemical pathways elicited in NK cells upon engagement of receptors responsible for either spontaneous or Ab-dependent recognition of target cells, although distinct, utilize ERK as one of their downstream molecules to regulate effector functions. 相似文献