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991.
Albert Z. Kapikian Anthony R. Kalica J.Wai-Kuo Shih W.Lee Cline Thomas S. Thornhill Richard G. Wyatt Robert M. Chanock Hyun Wha Kim John L. Gerin 《Virology》1976,70(2):564-569
The buoyant density in cesium chloride of the human reoviruslike (HRVL) agent of infantile gastroenteritis was studied utilizing electron microscopy and complement fixation (CF) for the detection of reoviruslike particles in fractions of the density gradient. Three virus positive stool filtrates were studied. “Full” reoviruslike particles had a density of 1.35–1.37 g/cm3, whereas “empty” particles had a density of 1.29 g/cm3. Peak CF activity coincided with the peak fraction of both the “full” and “empty” reoviruslike particles. In addition, by differential centrifugation, CF activity was also associated with the virion and not a “soluble” antigen. 相似文献
992.
Selective hyperthermia can be a feasible treatment modality for deep tissue abnormalities. It is accomplished by using a laser or ultrasound noninvasively to transfer energy to a desired target causing tissue damage. This process has two potential benefits to medical professionals: simplicity of procedure and safety to patient. However, optimizing these selective interactions is difficult due to the number of variables. We propose an optimization coefficient relating the dynamic and geometric parameters of selective hyperthermia, and proceed to measure it in an experimental setup consisting of a near-infrared laser and laser-absorbing dye. To simulate tissue, gelatin phantoms are created using a combination of water, intralipid, and gelatin. Our experiments use a 1.00-cm-diam spherical phantom that is homogeneously enhanced with an indocyanine green (ICG) solution and placed inside a nontarget phantom and irradiated by an 805-nm diode laser. Temperature measurements taken at different locations are analyzed so optimization coefficients can be calculated for different parameters. This optimization coefficient compares the difference in temperatures from inside and outside the target. Analysis of the values after thermal equilibrium provides information about the best parameter selection. Our findings indicate that the optimal ICG concentration and power combination for our tested parameters are 0.083% and 0.97 W, respectively. Based on our analysis, optimization can be obtained by using this coefficient to compare the selectivity of several parameter combinations. 相似文献
993.
Thomas Herzinger Gerold Kick Dagmar Ludolph-Hauser Bernhard Przybilla 《Annals of allergy, asthma & immunology》2004,92(6):673-675
BACKGROUND: Despite its worldwide and abundant consumption, beer has rarely been found to cause anaphylaxis. Barley malt contained in lager beers seems to be an important elicitor. OBJECTIVE: To report the unusual case of severe anaphylaxis following the ingestion of wheat beer. METHODS: A 59-year-old man experienced angioedema, generalized urticaria, and unconsciousness after ingestion of wheat beer. He tolerated lager beer well. For diagnostic evaluation, skin prick tests, oral challenge tests, and identification of specific IgE antibodies were performed. RESULTS: Skin prick test results with standard series of common aeroallergens and food allergens were negative with the exception of a 1 + reaction to wheat flour. The results of skin prick tests with native materials were positive for 2 brands of wheat beer and wheat malt shred but negative for baker's yeast, hops, and a brand of lager beer. Oral challenges with wheat beer or wheat flour elicited urticaria. By CAP-FEIA, specific IgE antibodies to wheat and barley flour but not to hops or baker's yeast were found in serum. Immunoblot analysis revealed that patient's IgE was bound to a protein of approximately 35 kDa in wheat extract. CONCLUSIONS: This is the first report, to our knowledge, on anaphylaxis to beer attributable to wheat allergy. 相似文献
994.
D. Willoughby Roger C. Thomas Christof J. Schwiening 《Pflügers Archiv : European journal of physiology》1998,436(4):615-622
We have evaluated the pyrene-based ratiometric fluorescent dye, 8-hydroxypyrene-1,3,6-trisulphonic acid (HPTS), by using
it in conjunction with glass pH-sensitive microelectrodes to measure intracellular pH (pHi) in voltage-clamped snail neurones. Intracellular acidification with propionic acid, and alkalinization following the activation
of H+ channels allowed the calibration of the dye to be compared with that of the pH microelectrode over the pH range 6.50–7.50.
HPTS calibrated in vitro and glass pH-sensitive microelectrodes produced similar absolute resting pHi values, 7.16±0.05 (n=10) and 7.17±0.06 (n=9) respectively in nominally CO2/HCO3
–-free saline. At both extremes of the pH range there were small discrepancies. At acidic pHi, 6.87±0.09 (n=5), the intracellular HPTS measurement differed by –0.08±0.03 pH units from the pH-sensitive microelectrode measurement.
At alkaline pHi,7.32±0.10 (n=5), HPTS measurements produced pH values that differed by +0.07±0.04 pH units from those of the pH-sensitive microelectrode.
Some of the discrepancy could be accounted for by the slow response of the recessed-tip pH-sensitive microelectrode (time
constant 77±15 s, n=3). Further experiments showed that HPTS, used at an intracellular concentration of 200 μM to 2 mM, did not block activity-dependent
pHi changes. The intracellular HPTS concentration was calculated by measurement of intracellular chloride during a series of
HPTS-KCl injections. Comparison of HPTS with 2′,7′-bis(2-carboxyethyl)-5,6-carboxyfluorescein (BCECF), at the same concentration,
showed that HPTS produces a larger change in ratio over the pH range 6.00–8.00.
Received: 19 February 1998 / Received after revision and accepted: 22 April 1998 相似文献
995.
Dal Zotto L; Quaderi NA; Elliott R; Lingerfelter PA; Carrel L; Valsecchi V; Montini E; Yen CH; Chapman V; Kalcheva I; Arrigo G; Zuffardi O; Thomas S; Willard HF; Ballabio A; Disteche CM; Rugarli EI 《Human molecular genetics》1998,7(3):489-499
We have recently reported isolation of the gene responsible for X- linked
Opitz G/BBB syndrome, a defect of midline development. MID1 is located on
the distal short arm of the human X chromosome (Xp22. 3) and encodes a
novel member of the B box family of zinc finger proteins. We have now
cloned the murine homolog of MID1 and performed preliminary expression
studies during development. Mid1 expression in undifferentiated cells in
the central nervous, gastrointestinal and urogenital systems suggests that
abnormal cell proliferation may underlie the defect in midline development
characteristic of Opitz syndrome. We have also found that Mid1 is located
within the mouse pseudoautosomal region (PAR) in Mus musculus , while it
seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a
recent acquisition of the M. musculus PAR. Genetic and FISH analyses also
demonstrated a high frequency of unequal crossovers in the murine PAR,
creating spontaneous deletion/duplication events involving Mid1. These data
provide evidence for the first time that genetic instability of the PAR may
affect functionally important genes. In addition, we show that MID1 is the
first example of a gene subject to X-inactivation in man while escaping it
in mouse. These data contribute to a better understanding of the molecular
content and evolution of the rodent PAR.
相似文献
996.
997.
James P. Thompson Richard B. Crandall Thomas J. Doyle IV Stephen A. Hines Catherine A. Crandall 《Parasitology research》1986,72(4):525-535
Eleven of 15 ferrets experimentally infected withBrugia malayi became amicrofilaremic after a brief patency; only four ferrets remained patent after 6 months of infection and two of these ferrets developed a high, persistent microfilaremia. Blastogenic responses of peripheral blood lymphocytes to antigens of microfilariae (mf), assayed in vitro, demonstrated an antigen sensitivity at prepatent, patent and postpatent periods of infection. Lymphocytes from ferrets with high microfilaremia had elevated background responses in culture which were directly correlated with the number of circulating mf. This background response was attributed to antigenic stimulation by mf present in the lymphocyte cultures; addition of mf to cultures of lymphocytes from postpatent ferrets induced responses equivalent to those observed in microfilaremic ferrets. Lymphocyte responses to the mitogen, concanavalin A, did not differ significantly among microfilaremic, amicrofilaremic and uninfected ferrets. Antibody in IgG to antigens of mf measured by ELISA and by immunoblots from SDS-PAGE showed similar patterns of response in ferrets which became amicrofilaremic and in the few ferrets which remained microfilaremic. Prausnitz-Kustner tests demonstrated no consistent differences in titers to microfilarial antigens between patent and amicrofilaremic ferrets. The results suggest a high level of immune responsiveness to antigens of mf in infected ferrets with no evidence of immunosuppression associated with prolonged microfilaremia or of major changes in immune responses with development of amicrofilaremic infections. 相似文献
998.
Riedl M Czech T Slootweg J Czernin S Hainfellner JA Schima W Vierhapper H Luger A 《Endocrine pathology》1995,6(2):159-166
This report describes a case of lymphocytic hypophysitis in a 63-year-old man who presented with symptoms of a pituitary mass
lesion associated with hypothyroidism and hypogonadism. Postoperative endocrinological testing demonstrated gonadotropic,
thyrotropic, and corticotropic hypopituitarism, and the patient was commenced on replacement therapy with hydrocortisone and
levothyroxine. Histological examination of the pituitary tissue obtained by transsphenoidal surgery revealed lymphocytic hypophysitis
without evidence of a pituitary adenoma. The vast majority of patients with lymphocytic hypophysitis are women particularly
during pregnancy and the puerperium. Until recently only four men were reported in the literature. The pathogenesis of lymphocytic
hypophysitis is uncertain but autoimmune mechanisms are possibly involved. 相似文献
999.
Paolo Lionetti Jo Spencer Emma J. Breese Simon H. Murch Jacqueline Taylor Thomas T. Macdonald 《European journal of immunology》1993,23(3):664-668
Staphylococcus aureus enterotoxin B (SEB) was added to explants of fetal human intestine in organ culture or administered into the lumen of fetal small intestine prior to culture. Both routes produced a massive increase in lamina propria T cells expressing Vβ33, and to a lesser extent, those expressing Vβ5 and Vβ12. SEB-activated lamina propria T cells produced interleukin-2 and interferon-Y and T cell activation was accompanied by tissue damage, which was inhibited by FK506. 相似文献
1000.
A two-dimensional finite element model incorporating cancellous bone inhomogeneity is used to study femoral head stress alterations
caused by changes from the usual articular contact patterns. The contact stress distributions, calculated from an earlier
mathematical analysis by Greenwald and O'Connor (16), are found to influence not only the adjacent subchondral bone, but relatively
distant parts of the head as well. Both abnormally large joint incongruity and abnormally low cartilage compliance cause load
to shift away from the superior “weight-bearing” area, out toward the periphery of the contact region. As a consequence, transverse
compressive stresses, which are of appreciable magnitude but which do not contribute to weight bearing, are built up throughout
much of the superior and central portions of the femoral head. Most small changes in the overall cartilage thickness or in
its thickness distribution, when considered in isolation from hip compliance changes, have only minor effects on the internal
stress distribution. An important exception is cartilage thinning at the superior margin, which can result in abrupt longitudinal
compressive stress concentrations. It is suggested that such alterations of the normal patterns of stress transmission may
contribute to sclerosis or to the formation of osteophytes or cysts in the osteoarthritic hip.
This study was aided by grants from the Easter Seal Research Foundation (#N7739), the National Science Foundation (#ENG78-05451),
the Barra Foundation, Inc., and the Western Pennsylvania Chapter of the Arthritis Foundation. The authors wish to acknowledge
the excellent service provided by the University of Pittsburgh Computer Center. The assistance of Mr. Gary E. Graf and Mrs.
Diana W. Montgomery are also appreciated. 相似文献