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101.
102.
P W Lowry W R Jarvis A D Oberle L A Bland R Silberman J A Bocchini H D Dean J M Swenson R J Wallace 《The New England journal of medicine》1988,319(15):978-982
Seventeen cases of otitis media caused by Mycobacterium chelonae were detected among patients seen at a single ear-nose-and-throat (ENT) office (Office A) in Louisiana between May 5 and September 15, 1987. All the patients had a tympanotomy tube or tubes in place or had one or more tympanic-membrane perforations, with chronic otorrhea that was unresponsive to standard therapy with antimicrobial agents. Middle-ear exploration in six patients revealed abundant granulation tissue; multiple granulomas and acid-fast bacilli were demonstrated on a section of tissue from one patient with a nonhealing mastoidectomy incision. Thirteen of the 14 ear isolates obtained from patients seen in Office A had the same unusual pattern of high-level resistance to aminoglycosides. M. chelonae and other nontuberculous mycobacteria were recovered from several sources of water in Office A, as well as in another ENT office (Office B) in a neighboring city that was visited by the index patient. Only one additional case was detected in Office B during the same period. Otologic instruments in Office A were cleaned in an ultrasonic bath with tap water and a liquid detergent; the contents of the bath were changed only once weekly. Instruments in Office B were placed in boiling water between patient examinations. This outbreak establishes M. chelonae as an agent of otitis media and underscores the need for high-level disinfection or sterilization of ENT instruments between examinations to prevent the transmission of this organism to patients in the office setting. 相似文献
103.
L E Wallace M Rowe J S Gaston A B Rickinson M A Epstein 《European journal of immunology》1982,12(12):1012-1018
Epstein-Barr virus (EBV)-specific cytotoxic T cell precursors, present in the circulation of previously infected (seropositive) individuals, have been reactivated in vitro by challenging with autologous EBV-transformed cells, and the reactivated populations subsequently expanded as interleukin 2 (IL2)-dependent cell lines. These lines were dominated by T cells possessing the cytotoxic/suppressor cell surface phenotype and, when tested for effector function in chromium-release assays, demonstrated potent EBV-specific, HLA-A and -B antigen-restricted cytotoxicity even when derived from seropositive donors whose initial cytotoxic response to in vitro reactivation was relatively weak. With all the lines tested from 10 seropositive donors, strong killing of autologous EBV-transformed cells was observed in the absence of any significant lysis of autologous mitogen-stimulated lymphoblasts or of a panel of EBV genome-negative cell lines sensitive to natural killing. Furthermore, the availability of IL2-expanded effectors cell populations allowed their being tested upon a wide panel of allogeneic EBV-transformed targets such that the dominant HLA-restricted reactivities within these populations could be identified. Monoclonal antibody blocking experiments confirmed that lysis of the autologous EBV-transformed cell line by IL2-expanded effectors could be specifically inhibited (a) by pretreatment of the target cells with antibodies binding to the HLA/beta 2-microglobulin complex, and (b) by pretreatment of the effector cells with the cytotoxic/suppressor T cell-specific antibody Leu 2a. 相似文献
104.
This article uses characters in popular films to demonstrate the theory and application of short term dynamic psychotherapy (STDP) in the treatment of performance anxiety. The reader is taught to identify affect phobias that are hypothesized to underlie performance anxiety. Similar in function to external phobias, affect phobias or internal phobias involve the avoidance of feelings (e.g., fear about feeling anger, shame about showing grief, pain about closeness), which thwarts adaptive responding and generates numerous behavioral problems. STDP treatment focuses on the restructuring of defenses, conflicted affects, and attachments. The resolution of the affect phobia requires systematic desensitization of affective responses (i.e., exposure and desensitization of underlying conflicted feelings). When patients learn to access adaptive forms of feelings, performance anxiety can often be resolved. 相似文献
105.
A. M. Mackenzie M Nolan K.-J. Wei M. A. Clements D. Gowanlock B. J. Wallace A. J. Gibbs 《Archives of virology》1998,143(5):903-914
Summary. A potyvirus, which we call ceratobium mosaic virus, has been detected in about one third of more than 100 plants representing
c. 33 orchid genera in two collections in Australia. It was detected using RT-PCR with redundant primers that are Potyviridae-specific and have additional sequences corresponding to either the SP6 or T7 bacteriophage promoters at their 5′-termini.
Thus the nucleotide sequence of the resulting PCR fragments, consisting of about 1.7 kb of the 3′ portion of the viral genome,
could be determined directly. Viral sequences obtained from five infected orchids indicate that they contained different isolates
of a single potyvirus species most closely related to the bean common mosaic group of potyviruses, but clearly distinct from
all whose virion protein genes have been reported to the international gene sequence databases.
Accepted December 18, 1997 Received September 9, 1997 相似文献
106.
Anne Hansen Ree Kristin Bjørnland Nils Brünner Harald Thidemann Johansen Kjetil Boye Pedersen Ansgar O. Aasen Øystein Fodstad 《Clinical & experimental metastasis》1998,16(3):205-215
Hormone-independent growth and invasiveness represent phenotypic properties acquired during early progression of breast cancer. We compared human mammary adenocarcinoma cells, MCF-7, which are estrogen-dependent and poorly metastatic, with the estrogen-independent and highly metastatic subline, MCF7/LCC1, with regard to expression of tissue-degrading factors of the matrix metalloproteinase (MMP)-and urokinase (uPA)-dependent degradative pathways, as well as for their in vitro invasive properties. Both cell lines showed low constitutive mRNA expression of the MMP inhibitor TIMP-1. Baseline expression of TIMP-2 mRNA was also very low in MCF-7 cells, whereas the MCF7/LCC1 level was much higher (~10- fold). Furthermore, both cell lines revealed low constitutive capacity to migrate in an in vitro invasion assay. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA; 100 nM) induced the mRNAs for TIMP-1 as well as for MMP-1, MMP-9, the uPA receptor, and the uPA inhibitor PAI-1, am ongst which only the responses of MMP-9 and PAI-1 were cell-specific. The mRNA levels of MMP-9 and PAI-1 were ~10-fold and ~15-fold higher in MCF7/LCC1 cells compared to MCF-7 cells. The secretion of immuno-reactive PAI-1 was considerably elevated (. 20-fold) in TPA-treated MCF7/LCC1 cells, whereas the TPA-dependent level of 92-kDa MMP-9 was only ~2-fold higher in MCF7/LCC1 cells than in MCF-7 cells. In both cell lines treatment with TPA was associated with an increase (~10-fold) in in vitro migration, which in the MCF7/LCC1 cells was significantly attenuated by a reconstituted basement membrane extract (Matrigel). These data suggest that TPA-responsive in vitro invasive properties that are probably associ-ated with PAI-1 expression may co-vary with progression from hormone-dependent to -independent breast cancer. © Rapid Science 1998 相似文献
107.
Hen Fluorescein-Labeled Gonococcal Lipopolysaccharide Antibody in the Delayed Fluorescent Antibody Technique for the Confirmation of Neisseria gonorrhoeae 下载免费PDF全文
F. E. Ashton R. A. Leitch M. B. Perry R. Wallace B. B. Diena 《Journal of clinical microbiology》1979,9(3):323-328
A fluorescent antibody reagent (termed anti-LPS conjugate) was prepared from sera obtained from hens immunized with gonococcal R-type lipopolysaccharide. The reagent was absorbed with Formalin-treated cells of Neisseria meningitidis. The anti-LPS conjugate gave uniform brilliant staining of Neisseria gonorrhoeae with little background fluorescence, thus making interpretation and reading of fluorescence simple. The conjugate did not significantly stain cultures of N. meningitidis, Neisseria lactamica, nonpathogenic Neisseria species, or other gram-negative bacteria. Several preparations of the conjugate provided the same specificity and reproducibility of staining. The anti-LPS conjugate was compared with Difco Laboratories fluorescent antibody conjugate for staining of N. gonorrhoeae. Both conjugates stained cells of the light and dark variants of gonococcal colony types 1 and 2, as well as cells of colony types 3 and 4. When used for the confirmation of N. gonorrhoeae, the anti-LPS and Difco conjugates stained 426 of 431 (98.8%) and 210 of 213 (98.6%) of the gonococcal cultures, respectively. Absorption of the anti-LPS conjugate with R-type lipopolysaccharide removed the staining of gonococci. However, absorption of Difco conjugate with R-type lipopolysaccharide did not remove the staining of gonococci, suggesting that the majority of fluorescein-labeled antibody present in the Difco conjugate is directed to gonococcal cell surface components other than lipopolysaccharide. The results of this study indicate that fluorescein-labeled gonococcal lipopolysaccharide antibody should be a reliable fluorescent antibody reagent for the confirmation of N. gonorrhoeae. 相似文献
108.
109.
110.
B Wallace 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(5):1374-1378
Three populations of Drosophila melanogaster that were daughter populations of two others with histories of high, continuous radiation exposure [population 5 (irradiated, small population size) gave rise to populations 17 (small) and 18 (large); population 6 (irradiated, large population size) gave rise to population 19 (large)] were maintained for 1 year with no radiation exposure. The frequency with which random combinations of second chromosomes taken from population 19 proved to be lethal changed abruptly after about 8 months, thus revealing the origin of a selectively favored element in that population. (This "element" may or may not have been the cause of the lethality.) A comparison of the loss of lethals in populations 17 and 18 with a loss that occurred concurrently in the still-irradiated population 5 suggests that a second, selectively favored element had arisen in that population just before populations 17 and 18 were split off. This element was on a nonlethal chromosome. The result in population 5 was the elimination of many lethals from that population, followed by a subsequent increase as mutations occurred in the favored nonlethal chromosome. Populations 17 and 18, with no radiation exposure, underwent a loss of lethals with no subsequent increase. The events described here, as well as others to be described elsewhere, suggest that populations may be subject to episodic periods of rapid gene frequency changes that occur under intense selection pressure. In the instances in which the changeover was revealed by the elimination of preexisting lethals, earlier lethal frequencies were reduced by approximately one-half; the selectively favored elements appear, then, to be favored in the heterozygous--not homozygous--condition. 相似文献