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991.
Pratelli A Tinelli A Decaro N Camero M Elia G Gentile A Buonavoglia C 《Journal of virological methods》2002,106(2):209-213
Comparative sequence analysis of the PCR products of the M gene and fragments of the pol1a and pol1b genes of canine coronavirus (CCoV) have demonstrated that two separate clusters of CCoV are present in dogs. This note describes a PCR assay to identify atypical CCoV strains with nucleotide substitutions in the M gene. A total of 177 faecal samples from dogs CCoV positive previously with the PCR assay were analysed. Sixty-two of the 177 samples were amplified with the PCR described in the present study and were thus considered atypical CCoVs. The specificity of the PCR typing assay was confirmed by sequence analysis of the PCR products. 相似文献
992.
OBJECTIVE: To analyze the long-term clinical outcome of dedifferentiated chondrosarcoma or chondrosarcoma with additional malignant mesenchymal component (CAMMC) of the larynx and compare the results with those of axial chondrosarcomas. STUDY DESIGN/METHODS: Two patients with CAMMC of the larynx (0.03%) were retrospectively identified within the archives of the Armed Forces Institute of Pathology between 1970 and 2001. We compared the clinical and histologic features of these two cases with those reported in the English literature (Medline 1966-2001) (Table I). RESULTS: Patient no. 1 was a 67-year-old man who presented with a 12-month history of hoarseness and was found to have a 4-cm mass involving the cricoid cartilage. Enucleation was performed and histologically demonstrated a dedifferentiated chondrosarcoma. Without additional intervention, the patient died after 136 months without evidence of disease. Patient no. 2 was a 41-year-old man who also presented with a 12-month history of hoarseness and dysphagia and was found to have a 5-cm mass involving the cricoid cartilage. A total laryngectomy was performed for the dedifferentiated chondrosarcoma. He is alive without evidence of disease at last contact (91 mo). CONCLUSION: CAMMC of the larynx are rare tumors but have a better prognosis than their axial counterparts (mean, 6 mo). Initial voice-sparing surgery can be followed with more aggressive surgery if recurrences develop. 相似文献
993.
Johnson TE Janes SJ MacDonald A Elia M Booth IW 《Archives of disease in childhood》2002,86(6):411-415
Background: There are few data on the optimal micronutrient composition of paediatric enteral feeds. The recent European Directive on Foods for Special Medical Purposes (1999/21/EC) did not distinguish between the composition of adult and paediatric feeds. Aims: To evaluate, in an open, observational study, the long term nutritional biochemistry of 12 children aged 1–6 years and/or 8–20 kg. Methods: The children were receiving at least 50% of their estimated average requirement (EAR) for energy from paediatric enteral formulae: 1.0 kcal/ml (Nutrison Paediatric Standard) or 1.5 kcal/ml (Nutrison Paediatric Energy Plus). Venous blood samples for trace elements, vitamins, and minerals were taken at study entry and six months later. Parents kept three day food and feed records every month. Results: Despite a median energy intake of only 75% EAR (range 52–158%), 67% (n = 8) achieved their reference nutrient intake (RNI) for all micronutrients. No significant micronutrient deficiencies were seen on blood analysis after six months. Eighty three per cent (n = 10) had vitamin B12 and 92% (n = 11) had copper intake >150% RNI. Fifty eight per cent (n = 7) had high plasma B12 (>733 µmol/l) and 75% (n = 9) had high serum copper (>22 µmol/l) concentrations. Conclusions: Children without excess losses maintain adequate micronutrient status on long term enteral feeding. Subjects had high blood concentrations of vitamin B12 and copper, and had high dietary intakes of these micronutrients. We suggest that the maximum nutrient guidelines for paediatric enteral feeds should be more clearly defined. 相似文献
994.
Decapitation and ecdysone therapy on the population dynamics of the Trypanosoma cruzi Dm28c clone in the stomach, small intestine and rectum of fifth-instar larvae of Rhodnius prolixus were investigated. Parasites were not found in the small intestine and rectum of decapitated insects after 10 days post-infection (p.i.). Decapitated ecdysone-supplemented insects sustained the flagellate infection in both gut compartments. In the rectum, the population density of parasites increased 5-fold in ecdysone-treated decapitated larvae and 7-fold in control insects. Epimastigote forms dominated with 40-65%, intermediate stages and round forms varied over 10-35% in the stomach, small intestine and rectum in both insect groups. Low numbers of metacyclic trypomastigotes were observed in the stomach and small intestine of the control group and decapitated insects supplemented with ecdysone but, at 15 days p.i., this form of flagellate reached about 20% in the rectum of the control insects. In the entire gut, at 30 days p.i., 23% of parasites in the control group and 8% in the decapitated insects treated with ecdysone were found. These results indicate that a head factor, possibly the prothoracicotropic hormone from the brain which stimulates ecdysone production by the prothoracic glands, may act directly or indirectly to stimulate the development of epimastigotes and round forms of the parasite and that a single ecdysone treatment is not able to fully reverse metacyclogenesis in decapitated R. prolixus. 相似文献
995.
996.
Ganzarolli SM Rached RN Garcia RC Del Bel Cury AA 《Journal of oral rehabilitation》2002,29(8):787-790
Well-fitted dentures prevent hyperplasic lesions, provide chewing efficiency and promote patient's comfort. Several factors may affect final adaptation of dentures, as the type of the acrylic resin, the flask cooling procedure and the water uptake. This investigation evaluated the effect of water storage and two different cooling procedures [bench cooling (BC) for 2 h; running water (RW) at 20 degrees C for 45 min] on the final adaptation of denture bases. A heat-cured acrylic resin (CL, Clássico, Clássico Artigos Odontológicos) and two microwave-cured acrylic resins [Acron MC, (AC) GC Dent. Ind. Corp.; Onda Cryl (OC), Clássico Artigos Odontológicos] were used to make the bases. Adaptation was assessed by measuring the weight of an intervening layer of silicone impression material between the base and the master die. Data was submitted to ANOVA and Tukey's test (0.05). The following means were found: (BC) CL=0.72 +/- 0.03 a; AC=0.70 +/- 0.03 b; OC=0.76 +/- 0.04 c//(RW) CL= 1.00 +/- 0.11 a; AC=1.00 +/- 0.12 a; OC=0.95 +/- 0.10 a. Different labels join groups that are not statistically different (P > 0.05). Comparisons are made among groups submitted to the same cooling procedure (BC or RW). The conclusions are: interaction of type of material and cooling procedure had a statistically significant effect on the final adaptation of the denture bases (P < 0.05); water storage was not detected as a source of variance (P > 0.05) on the final adaptation. 相似文献
997.
998.
999.
1000.
Wang H Hosiawa KA Garcia B Shum JB Dutartre P Kelvin DJ Zhong R 《Xenotransplantation》2003,10(4):325-336
Searching for a novel immunosuppressive agent to effectively prevent acute vascular rejection (AVR) is essential for success in clinical xenotransplantation. We previously reported that Lewis rat hearts transplanted into BALB/c mice developed typical AVR in 6 days. The present study was undertaken to determine the efficacy of LF 15-0195, a new immunosuppressive analog of 15-deoxyspergualin in the prevention of AVR in a rat-to-mouse cardiac xenograft model. We transplanted 2-week old Lewis rat hearts into BALB/c mice. Four groups were included in this study: untreated recipients and cyclosporin A (CsA) treated recipients were controls; LF 15-0195 treated recipients or LF 15-0195 combined with CsA treated recipients were experimental groups. Mouse recipients received either LF 15-0195 2 mg/kg subcutaneously from day-1 to post-operative day 14, or CsA 15 mg/kg subcutaneously daily, from day 0 to endpoint rejection, or the two drugs in combination. We observed that high dose CsA did not inhibit AVR and the graft was rejected in 11.3 +/- 1.9 days. Graft histology and immunohistology showed typical AVR, characterized by interstitial hemorrhage, intravascular fibrin deposition, thrombosis, and massive deposition of anti-rat immunoglobulin G (IgG) and immunoglobulin M (IgM). Serum xenoreactive antibodies (xAbs) were markedly elevated in these animals as well. In contrast, we observed that treatment with LF 15-0195 alone significantly prolonged graft survival to 19.3 +/- 0.7 days. Notably, xAbs were significantly decreased and the rejection pattern of these grafts was cell-mediated rejection (CMR), instead of AVR. When CsA was combined with LF 15-0195, the graft mean survival time was further increased to 58.5 +/- 17.3 days. Antibody production and T-cell infiltration were significantly inhibited at the terminal stages of graft survival and pathology showed striking attenuation of both AVR and CMR. Sequential studies on days 6 and 14 demonstrated that LF 15-0195 either alone or combined with CsA completely inhibited antibody production. However, intragraft infiltration by Mac-1 positive cells including natural killer cells, macrophages and granulocytes in LF 15-0195 treated recipients was similar to that of untreated recipients. We conclude that LF 15-0195 effectively prevented AVR by markedly inhibiting the production of anti-donor IgG xAbs. Also, treatment with short course LF 15-0195 and continuous CsA significantly reduced T-cell infiltration. Studies to test this therapy in inhibiting AVR in a pig-to-non-human primate xenotransplantation model are underway. 相似文献