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991.
Ten protein and enzyme polymorphic systems, viz. haemoglobin, albumin, transferrin, adenosine deaminase, adenylate kinase phosphoglucomutase, esterase-D, glyoxalase, alkaline phosphatase and amylase were studied in numigall (guinea fowl x chicken hybrids) to assess structural gene expression and regulatory gene divergence between the parental species. The investigation revealed presence of both the maternal and paternal electrophoretic components in case of adenosine deaminase, alkaline phosphatase, amylase, albumin and transferrin although no clear differences could be identified for haemoglobin and glyoxalase. Esterase-D and adenylate kinase phenotypes showed a dominance of the chicken type. 相似文献
992.
Although barium studies and CT are useful in assessing abdominal pathology in tuberculosis, imaging findings are not always specific and a histopathological or bacteriological confirmation is often required. The aim of the present study was to evaluate the role of ultrasound (US) guided fine needle aspiration cytology (FNAC) in the diagnosis of abdominal tuberculosis in patients with non-palpable lesions detected on US/CT. FNAC was performed on 31 sites in 30 patients. The sites included enlarged lymph nodes (n = 14), focal lesions in liver (n = 2) and spleen (n = 8), and thickened bowel in the ileocaecal region (n = 7). The results were classified cytomorphologically into four groups: (1) definite evidence of tuberculosis; (2) presumptive evidence of tuberculosis; (3) suggestive of tuberculosis; and (4) negative for tuberculosis. 18 of the 31 FNACs (58%) revealed a positive diagnosis of tuberculosis (definite evidence in nine patients and presumptive evidence in nine patients). 13 of the 31 FNACs (42%) showed either necrosis alone (n = 4) or negative results (n = 9). Zeihl-Neelson staining for acid-fast bacilli on direct smear was positive in only nine patients (29%). Splenic and lymph nodal FNAC had a high sensitivity (87.5% and 78.6%, respectively) in the diagnosis of tuberculosis. None of the bowel and liver FNACs was diagnostic. No complications were encountered. US guided FNAC offers a safe and accurate method of achieving a diagnosis in patients with suspected abdominal tuberculosis who present with radiologically demonstrable but non-palpable lesions, especially those involving lymph nodes and spleen. 相似文献
993.
CA Long SK Teplick JC Brandon GH Harb K Yan ML Baker 《Canadian Metallurgical Quarterly》1994,5(3):479-484
PURPOSE: To determine what interaction and effect different cholesterol gallstone solvents have on catheters used for gallstone chemolysis. MATERIALS AND METHODS: Five types of catheters used for biliary procedures were chosen: polyethylene, Percuflex, silicon, Silitek, and polyurethane. The solvents chosen were methyl tert-butyl ether, ethyl propionate, isopropyl acetate, and N-propyl acetate. After incubation of the catheters in the solvents for 72 hours, they were air dried. Weight and area changes were determined for each catheter. Additionally, carbon-13 nuclear magnetic resonance (NMR) spectroscopy was performed for analysis of composition changes. RESULTS: Three catheters--silicone, Silitek, and polyurethane--showed changes in their physical characteristics that would make them less desirable for stone chemolysis. The silicone catheter showed changes in elastic texture as well as marked weight reduction. The Silitek and polyurethane catheters had similar, but less dramatic changes. C-13 NMR analysis of collected solvents showed that commonly used plasticizers were leached out of some catheters. CONCLUSION: These results suggest that all catheters are not suitable for use with all solvents. The choice of catheter should be made based on the solvent in use. The polyethylene catheter performed best under the conditions and endpoints used in this study. 相似文献
994.
We report a case of myelodysplastic syndrome (MDS) with myelofibrosis and pulmonary tuberculosis who had marked basophilia in the peripheral blood. A clonal karyotypic abnormality characterized by trisomy 8 was demonstrated by cytogenetic analysis. By correlation of cell morphology with results of fluorescence in situ hybridization using a chromosome 8 probe, we demonstrated that the basophils were not reactive but belonged to the neoplastic MDS clone. 相似文献
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998.
The fusion (F) protein of bovine respiratory syncytial virus (BRSV) was expressed by using a baculovirus vector. Antigenicity was tested by immunofluorescence analysis with F-specific monoclonal and polyclonal antibodies. Antibodies to recombinant F protein raised in a rabbit neutralized BRSV and human respiratory syncytial virus infectivity when tested in a plaque reduction assay. The recombinant F protein was evaluated as a source of antigen in an enzyme-linked immunosorbent assay (ELISA), and this ELISA was compared with the virus neutralization (VN) test for detecting BRSV antibodies in 10 consecutive serum samples from four calves vaccinated with a live modified BRSV vaccine and from two nonvaccinated control calves. The ELISA with the baculovirus-expressed F protein as an antigen compared favorably with the VN test and is a rapid, sensitive, and specific method for detecting serum antibodies to BRSV. 相似文献
999.
Modulation of the activity of RNase E in vitro by RNA sequences and secondary structures 5' to cleavage sites 总被引:1,自引:0,他引:1
The endoribonuclease RNase E is believed to initiate the degradation of many mRNAs in Escherichia coli, yet the mechanism by which it recognizes cleavage sites is poorly understood. We have prepared derivatives of the mRNA encoding ribosomal protein S20 which contain a single major RNase E cleavage site at residues 300/301 preceded by variable 5' extensions. Three of these RNAs are cleaved in vitro with significantly reduced efficiencies relative to the intact S20 mRNA by both crude RNase E and pure Rne protein (endonuclease component of RNase E). In all three substrates as well as in the full-length mRNA the major cleavage site itself remains single-stranded. One such substrate (t84D) contains a 5' stem-loop structure characterized by three noncanonical A-G pairs. Removal or denaturation of the stem restores efficient cleavage at the major RNase E site. The other two contain single-stranded 5'-termini but apparently lack cleavage sites near the termini. Our data show that sensitivity to RNase E can be influenced by distant structural motifs in the RNA and also suggest a model in which the initial recognition and cleavage of a substrate near its 5' end facilitates sequential cleavages at more distal sites. The model implies that RNase E contains at least a dimer of the Rne subunit and that the products of the first cleavage are retained by Rne prior to the second cleavage. 相似文献
1000.