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排序方式: 共有256条查询结果,搜索用时 15 毫秒
1.
Separate injections of Haemophilus influenzae type b capsular polysaccharide-tetanus conjugate (PRP-T) vaccine and diphtheria-tetanus-pertussis (DTP) reconstitution of freeze-dried PRP-T vaccine with liquid DTP vaccine have been shown to be safe and immunogenic in infants. The present study was conducted to test the safety and immunogenicity of the liquid combination vaccine administered to young infants in the dual-chamber syringe. The study was a monocenter, open clinical trial of 3 month-old infants receiving PRP-T and DTP vaccines in the dual-chamber syringe reconstituted prior to injection. Healthy infants were immunized according to a 3, 4 and 5 months-of-age schedule. The vaccine was administered in a dual-chamber syringe, ready to use with two chambers. The proximal chamber contained freeze-dried PRP-T and the distal chamber contained liquid combination-vaccine DTP. The freeze-dried PRP-T vaccine was reconstituted with the liquid DTP vaccine in the same unidose dual-chamber syringe (0.5 mL) and was injected intramuscularly into the deltoid region. Blood sampling was performed prior to vaccination at 3 months of age and after the third vaccination at 6 months. The primary end-point was the serological response to PRP-T vaccine as expressed by the percentage of infants with an antibody titer greater than or equal to 1 microgram/mL. The reactogenicity was expressed as the percentage of reported local and systemic reactions. A total of 108 infants were included in the study and received the dual-chamber syringe vaccine. After the third injection, all the infants had a PRP antibody titer greater than or equal to 0.15 microgram/mL and 94.4% of infants had a PRP antibody titer greater than or equal to 1 microgram/mL; the pertussis agglutinin titers were over the threshold 40 and 80 in all infants and 98.1% were over the threshold 320. After the third injection, all the infants had diphtheria antibody titers greater than 0.1 IU/mL and 83.3% had titers greater than 1 IU/mL; all the infants had tetanus antibody titers greater than 0.1 IU/mL and 97.2% had results over 1 IU/mL. Thirty-seven infants (34.6%) had local reactions and 64.5% had systemic reactions. The dual-chamber syringe may reduce the cost of vaccine delivery, as well as the workload, and increase the vaccine acceptability and coverage rate of vaccines. 相似文献
2.
UR Juergens SC Christiansen DD Stevenson BL Zuraw 《Canadian Metallurgical Quarterly》1995,96(2):148-156
Aspirin-sensitive patients may be desensitized through a graded series of exposures to aspirin. We investigated the underlying mechanism of aspirin desensitization by measuring the release of leukotrienes B4 and C4 from calcium ionophore-stimulated peripheral blood monocytes. Compared with monocytes from normal volunteers (n = 5), monocytes from patients with aspirin-sensitive asthma (n = 10) released increased amounts of thromboxane B2 (1060 +/- 245 pg/ml vs 456 +/- 62 pg/ml), leukotriene B4 (861 +/- 139 pg/ml vs 341 +/- 44 pg/ml), and leukotriene C4 (147 +/- 31 pg/ml vs 56 +/- 6 pg/ml) at baseline. After aspirin desensitization, thromboxane B2 release was almost completely suppressed in both groups. Leukotriene B4 release was significantly decreased in the aspirin-sensitive group (484 +/- 85 pg/ml) but not in the normal subject group (466 +/- 55 pg/ml). The need for prednisone decreased significantly after patients were desensitized to aspirin (10.4 +/- 2.2 mg/day to 1.6 +/- 2.8 mg/day). These results demonstrate that desensitization to aspirin results in decreased monocyte leukotriene B4 release. On the basis of the bronchospastic and inflammatory potential of leukotrienes, the decrease in leukotriene release may contribute to the clinical improvement seen after aspirin desensitization. 相似文献
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Extrarenal rhabdoid tumors of soft tissue: a clinicopathologic and immunohistochemical study of 18 cases 总被引:1,自引:0,他引:1
JC Fanburg-Smith M Hengge UR Hengge JS Smith M Miettinen 《Canadian Metallurgical Quarterly》1998,2(6):351-362
Rhabdoid tumor is a well-accepted clincopathologic entity among childhood renal neoplasms; similar tumors have been described in extrarenal locations. We present the clinicopathologic profile and the immunohistochemical features of a series of soft tissue rhabdoid tumors. Twenty-eight cases coded as extrarenal rhabdoid tumor (ERRT), RT, possible ERRT, and "large cell sarcoma" were retrieved from the Armed Forces Institute of Pathology soft tissue registry. The tumors were reclassified according to strict criteria by light microscopy, clinical information, immunohistochemistry, and, in some cases, electron microscopy. Soft tissue rhabdoid tumor (STRT) was defined as (1) a tumor composed of noncohesive single cells, clusters, or sheets of large tumor cells with abundant glassy eosinophilic cytoplasm, an eccentric vesicular nucleus, and an extremely large nucleolus; (2) positivity for vimentin and/or cytokeratin or other epithelial markers by immunostaining; and (3) exclusion of other tumor types with rhabdoid inclusions (melanoma, other sarcomas, carcinoma). Eighteen cases met our criteria for soft tissue rhabdoid tumors. The median patient age was 13 years (range, 6 months to 56 years). Ninety-four percent of STRT cases were positive for vimentin and 59% for pan-cytokeratin. Sixty-three percent and 60% were positive for CAM 5.2 and EMA, respectively. Seventy-nine percent stained for at least one epithelial marker; 76% stained for both vimentin and epithelial markers simultaneously. Forty-two percent stained for MSA, and 14% for CEA and SMA. CD99, synaptophysin, CD57 (Leu-7), NSE, and focal S100 protein were identified in 75%, 66%, 56%, 54%, and 31% of the STRT cases, respectively. All STRT cases examined were negative for HMB-45, chromogranin, BER-EP4, desmin, myoglobin, CD34, and GFAP. Follow-up examination in 61% of the STRT patients revealed that 64% of patients died of disease within a median follow-up interval of 19 months (range, 4 months to 5 years); 82% had metastases to lung, lymph nodes, or liver; 22% had local recurrences before metastasis; and 18% were alive without known disease status (median, 5.5 years). Soft tissue rhabdoid tumor is a highly aggressive sarcoma, predominantly of childhood. Besides having nearly consistent coexpression of vimentin and epithelial markers, STRTs show positivity for multiple neural/neuroectodermal markers that overlap with those of primitive neuroectodermal tumor. 相似文献
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The influence of sodium chloride, sucrose and pH on the pasting characteristics of corn starch phosphate monoesters (SPM) with different degrees of substitution (D.S.) were investigated. The SPM with D.S. of 0.055 showed a marked decrease of the initial viscosity with an increase of sucrose concentration up to 55%. The opposite effect was observed for the SPM with D.S. of 0.113 and 0.147. All the SPM presented a higher final viscosity with an increase of sucrose concentration. A significant decrease of the initial viscosity and of all other pasting characteristics of the initial viscosity and of all other pasting characteristics was noted in the presence of sodium chloride. The phosphated starches were not stable in acidic medium and showed some reduction of their pasting characteristics in alkaline medium. 相似文献
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Isosteric Heat of Adsorption of n-Ethane on Zeolites NaX and NaY Using a volumetric method isotherms of adsorption of ethane on zeolites NaX and NaY were measured. The Clausius-Clapeyron equation was used to calculate the isosteric heat of adsorption of the paraffin on both molecular-sieves. These enthalpies show a linear dependence of the amount of adsorbed molecules. The zeolite with the higher charge density shows a larger heat of adsorption. The difference in the heat of adsorption is explained by adsorption on different centers in the cavity of both zeolites. 相似文献
9.
By exploiting the rapid increase in available sequence data, the definition of medically relevant protein targets has been improved by a combination of: (i) differential genome analysis (target list): and (ii) analysis of individual proteins (target analysis). Fast sequence comparisons, data mining, and genetic algorithms further promote these procedures. Mycobacterium tuberculosis proteins were chosen as applied examples. 相似文献
10.
v-raf suppresses apoptosis and promotes growth of interleukin-3-dependent myeloid cells 总被引:1,自引:0,他引:1
JL Cleveland J Troppmair G Packham DS Askew P Lloyd M González-Garcia G Nu?ez JN Ihle UR Rapp 《Canadian Metallurgical Quarterly》1994,9(8):2217-2226
Interleukin-3 (IL-3) is required for the proliferation, survival and differentiation of myeloid progenitors. In the absence of IL-3, murine myeloid 32D.3 cells accumulate in the G1 phase of the cell cycle and subsequently undergo programmed cell death, or apoptosis. Here we demonstrate that enforced expression of the v-raf oncogene suppresses apoptosis of myeloid 32D.3 cells following the withdrawal of IL-3. Surprisingly, steady state levels of Bcl-2, an oncogene known to suppress apoptosis, were not dependent upon IL-3 in 32D.3 cells and its levels were not augmented in v-raf clones. This suggests that ability of v-raf to suppress apoptosis in the absence of ligand is either Bcl-2 independent or that v-raf kinase promotes Bcl-2 function. v-raf also promoted growth of these cells in the presence of IL-3. v-raf clones proliferated at an increased rate due to a shortened G1 phase and had decreased requirements for IL-3 for growth. Therefore, transformation of myeloid cells by v-raf involves signaling pathways which promote both cell cycle progression and cell survival. 相似文献