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71.
A cytoskeletal actin gene in the mosquito Anopheles gambiae 总被引:2,自引:0,他引:2
C. E. Salazar D. Mills Hamm D. M. Wesson C. B. Beard V. Kumar F. H. Collins 《Insect molecular biology》1994,3(1):1-13
Five actin genes have been identified in the mosquito Anopheles gambiae , and a constitutively expressed actin gene has been chosen for detailed analysis. We have physically mapped and sequenced this gene and six associated cDNAs, including translated coding regions, as well as the 5 and 3 flanking sequences. Analysis of stage-specific RNA shows this gene to be present in all stages of mosquito development and in an established A. gambiae cell line, thus indicating a cytoskeietal actin. In the sequence of the translated coding region and in pattern of expression, this gene is very similar to the cytoskeietal actin genes of Droso-phila melanogaster , and in sequence, equally similar to the Artemia cytoskeietal actin gene 403 (99.2% identity among the three amino acid sequences). Sequencing of this A. gambiae actin gene (designated actWior its location in chromosome division 1D) and selected cDNAs shows that it possesses three alternative leader sequences; thus the gene appears to have three alternative promoters. These promoters should ultimately prove useful in the production of transgenic constructs for constitutive expression. 相似文献
72.
T H Bourne F Lawton A Leather S Granberg S Campbell W P Collins 《Ultrasound in obstetrics & gynecology》1994,4(1):73-75
There is sometimes a discrepancy between the apparent thickness of postmenopausal endometria, as determined by transvaginal ultrasonography, and the examination of endometrial biopsies. We describe a case which showed that tamoxifen (20 mg/day over 12 months) decreased impedance to blood flow in the uterine arteries and increased the apparent thickness of the endometrium. Conversely, the analysis of biopsies suggested the presence of an atrophic endometrium. The introduction of sterile saline into the uterine cavity during a repeat ultrasound scan revealed the presence of a large, free-floating endometrial polyp, which was subsequently difficult to see by hysteroscopy. 相似文献
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Human interleukin 3 (IL-3) is a multipotential cytokine that supports the growth of early hematopoietic progenitors and promotes their response to other, later-acting cytokines. We found that IL-3 was able to induce the expression of interleukin 2 (IL-2) receptor (IL-2R) (CD25) on a subset of early myeloid cells in normal human bone marrow that had been first depleted of mature hematopoietic cells and E-rosette-positive T cells by treatment with soybean lectin and sheep erythrocytes (SBA-E-BM). Immunofluorescence analysis revealed that the CD25+ cells were contained almost entirely within the lymphoblastoid gate of the IL-3-cultured marrow. CD25 was undetectable on freshly isolated marrow and less than 10% CD25+ cells could be detected following liquid culture at 37 degrees C in the presence of 10% human serum, 10% fetal calf serum, or under serum-free conditions. Addition of IL-3 (100 U/ml) significantly increased the expression of CD25 to 37%, 31%, and 24%, respectively. CD25 could also be induced by granulocyte-macrophage colony-stimulating factor (GM-CSF), but no IL-2R was detectable following exposure to granulocyte colony-stimulating factor (G-CSF), macrophage colony-stimulating factor (M-CSF), interleukin 1 (IL-1), interleukin 4 (IL-4), or IL-2. Expression of CD25 was dependent on the dose of IL-3 or GM-CSF added and was maximal within 24 h of exposure. Two-color immunofluorescence analysis demonstrated that CD25 was not expressed by cells of lymphoid lineage or by mature monocytes, but rather was present on cells that coexpressed CD13, CD33, CD34, MY8, and HLA-DR, and that lacked CD14 or CD11b, thus placing the CD25+ cells at or near the myeloblast stage of differentiation. An identical phenotype was found for CD25+ cells induced by GM-CSF. Cycloheximide completely inhibited the IL-3-induced expression of CD25, indicating the necessity for protein synthesis, and although most of the CD25+ cells were in G0/G1 phase, 25% of the cells were in S or G2M phase, indicating that receptor expression was not cell-cycle dependent. The p75 chain of IL-2R was not detected on the CD25+ cells. IL-3 was also found to directly induce CD25 in greater than 46% of SBA-E-BM enriched for CD34+ cells by panning. Consistent with the expression of only p55 IL-2R, the functional activity of IL-2 on enriched CD34+ cells exposed to IL-3 could not be demonstrated in either granulocyte-macrophage colony-forming unit (CFU-GM) assays or proliferation assays.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Contact dermatitis in patients with leg ulcers 总被引:3,自引:2,他引:1
100 patients with leg ulcers were patch tested against a standard battery of allergens. The readings were carried out daily from the 2nd to the 7th days. 55 patients showed positive reactions to one or more allergens. 32% of positive reactions developed for the first time after 48 h and 11% after 72 h. No single day or combination of two days gave 100% positive results. A single reading on the 4th day gave the highest number of positive reactions at 92%. The prevalence of positive patch tests was significantly higher in patients with surrounding eczema, and in patients with positive patch tests the ulcer duration was significantly longer than in those with negative patch tests. The total number of positive results in individuals increased linearly with the duration of the ulcer. Of allergens to which the ulcer was exposed, the occurrence of multiple sensitivity was significantly greater than predicted from the prevalence of individual sensitivities. However, there was no association between medicaments and metal sensitivity. This, together with the absence of an exponential rise in the number of allergens with the duration of ulcer, does not support the theory of systemic ampliative allergy. 相似文献
78.
Deborah D Albright Diane Jordan-Wagner Diane C Napoli Amy L Parker Fonzie Quance-Fitch Bonnie Whisman Jacob W Collins Larry L Hagan 《Annals of allergy, asthma & immunology》2006,97(4):521-527
BACKGROUND: Multicolored Asian lady beetles (Harmonia axyridis) have been used as a biological control agent against crop-destroying aphids in the United States. Outside their natural habitat, H. axyridis seeks refuge in homes during fall and winter, leading to patient complaints and symptoms of rhinitis, wheezing, and urticaria on exposure to the beetles. OBJECTIVE: To gain a better understanding of the character and spectrum of allergic disease provoked by exposure to home-infesting lady beetles. METHODS: Eight patients with allergic symptoms suspected of being caused by H. axyridis and consistent with an IgE-mediated process were identified and interviewed. A whole-body extract from H. axyridis was prepared. Western blots using the patients' serum identified specific IgE antibodies in the extract. Through a novel technique, immunohistochemical analysis using beetle sections overlayed with patient serum was performed. A random survey of allergists from across the United States was also performed to evaluate experience with cases of lady beetle allergy. RESULTS: Western blots revealed IgE binding to 5 proteins with molecular weights of approximately 8.6, 21, 28, 31, and 75 kDa. Specific IgE bound to proteins localized in the beetle's mouth and leg areas. The allergist survey revealed positive responses in North Central, Mid-Atlantic and New England states. CONCLUSION: In 8 patients with allergic symptoms on exposure to high levels of lady beetles, specific IgE bound to proteins from H. axyridis. There was also an increased frequency of suspected cases of lady beetle allergy in endemic areas. 相似文献
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Computerised videokeratography is increasing in sophistication and accuracy. The Orbscan II Videokeratographer combines the advantages of Placido derived and slit-scanning derived topography, to acquire shape information on the posterior surface of the cornea. The purpose of this paper is to construct a model of slit-scanning elevation topography and highlight potential sources of variation in this methodology. Ray tracing calculations were performed on a defined, theoretical, spherical model to obtain a pachymetric measurement. These calculations were tested by comparing the pachymetry measurement derived from the model, over a refractive index shift from 1.376 to 1.400 with the pachymetry measurement obtained by Orbscan II, of a human eye, with an identical alteration in refractive index. The two methods of measurement differed by only 0.157 microm, suggesting that the model is a good representation of slit-scanning elevation topography, and that refractive index variations have only a minimal effect on Orbscan II pachymetry measurement. 相似文献