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851.
OBJECTIVES: To investigate the significance of serum levels of soluble tumour necrosis factor receptor I (sTNF-RI) as a potential biochemical marker in women with cervical cancer. DESIGN: A prospective, case-controlled study. PARTICIPANTS: Seventy-one women with cervical cancer and 33 women with myoma were enrolled in this study. METHODS: Pre-operative serum levels of sTNF-RI were measured with a standard enzyme-linked immunosorbent assay utilising murine monoclonal antibody against sTNF-RI. MAIN OUTCOME MEASURES: All data in both groups were evaluated and correlated with the pre-operative serum levels of sTNF-RI. Data analysis was carried out using ANOVA with multiple comparison and linear regression. RESULTS: The mean serum level of sTNF-RI in the cervical cancer group was significantly lower than that in the myoma group (P < 0.001). The sTNF-RI levels decreased sequentially with disease progression from Stage Ia to IIb in women with cervical cancer. The mean serum level of sTNF-RI was also significantly lower in women with positive lymph node (P < 0.05) or recurrent cancer (P < 0.001). A negative correlation was observed between serum levels of sTNF-RI and tumour size (r = -0.622, P < 0.0001). CONCLUSIONS: Decreased pre-operative serum levels of sTNF-RI are observed in women with cervical cancer. The results do not support that the use of sTNF-RI as a biochemical marker for cervical cancer.  相似文献   
852.
PURPOSE: The purpose of this study was to evaluate the outcome of patients with healed moderate to severe contact lens-associated corneal infectious ulcers who were re-fit with contact lenses. METHODS: We retrospectively studied patients who were fit with contact lenses on our service and who had had moderate to severe corneal infectious ulcers associated with previous contact lens use. Six patients were included in the study. RESULTS: Gas permeable contact lenses were fit in five patients, and a soft contact lens was fit in one patient. Successful fit was achieved in all cases and visual acuities were equal to or better than 20/30 in all patients. No significant complications were observed after a mean follow-up of 23 months (range, 6-45 months). CONCLUSION: In this small series of patients with a history of moderate to severe contact-lens related infectious keratitis, no complications were observed after contact lenses were refit. Contact lens wear in patients with a history of infectious keratitis may be safe and useful in order to achieve visual rehabilitation.  相似文献   
853.
Acute cholangitis is associated with significant morbidity and mortality. Endoscopic drainage procedures have been shown to be a safe and effective mode of treatment in acute cholangitis. As there is paucity of large series on endoscopic management of acute cholangitis, a study was performed to evaluate safety and efficiency of endoscopic biliary decompression in acute cholangitis. The study included 89 consecutive patients (mean age 55+/-15 years; range 35-70 years; 50 males) with acute cholangitis requiring biliary drainage. Main presenting features were upper abdominal pain (84%), fever with chills (90%) and jaundice (74%). Altered sensorium, hypotension, features of peritonitis and acute renal failure were present in 15, 11, 18 and 5%, respectively. Endoscopic procedures performed were endoscopic sphincterotomy (ES) with stone extraction (n=40); ES with endoscopic nasobiliary drainage (ENBD; n=30); ENBD without ES (n=8); and ES with stent placement (n=11). Of the 89 patients, 85 (95%) responded within 48-72 h. Endoscopic common duct clearance could be achieved in 58 of 78 (74%) patients, whereas in 11 patients undergoing stent placement, stone extraction was not attempted. Complications included post-sphincterotomy bleed (n=2), retroduodenal perforation (n=1) and acute pancreatitis (n=1) with an overall complication rate of 4.4%. All the complications were seen in patients undergoing ES with stone extraction. Mortality was 3.3%. In conclusion, endoscopic biliary drainage is a safe and effective mode of treatment for acute cholangitis. Endoscopic nasobiliary drainage or stent placement is safer than ES in acute cholangitis as an initial step.  相似文献   
854.
The method based on the combination of polymerase chain reaction (PCR) and fluorescence polarization is presented. A targeted DNA was amplified with a 5'-fluorescein labeled primer, using a 256 bp DNA fragment of stx2 gene in Escherichia coli O157:H7 (188-443 bp) as a template. The fluorescence anisotropy of the 5'-fluorescein labeled primer increased upon the polymerization through Taq polymerase. The conversion of primer to PCR product was quantitatively monitored by anisotropy ratio and relative hydrodynamic volume. This system was also applied to the determination of E.coli O157:H7.  相似文献   
855.
856.
OBJECTIVE: To determine the value of follow-up abdominal computed tomography in patients with splenic trauma managed nonoperatively. DESIGN: Retrospective chart review. MATERIALS AND METHODS: A total of 108 consecutive patients with splenic injuries treated at a single institution from 1990 to 1996 were studied. All admission and follow-up computed tomographic (CT) scans were reviewed by the authors. RESULTS: Initial management was surgical in 35 patients (32%) and intentionally nonoperative in 73 patients (68%). Nonoperative management was successful in 45 of 49 adults (92%) and 21 of 24 children(88%). Sixty-two follow-up abdominal CT scans were obtained in 49 patients. Information that affected management was evident on only one follow-up CT scan performed in the absence of clinical indications. Potential savings in hospital and physician charges for routine follow-up CT scans in this study were $54,302.00. CONCLUSIONS: Follow-up abdominal CT scans are not routinely necessary in patients with splenic injuries managed nonoperatively.  相似文献   
857.
Classical genetic and molecular data show that genes determining disease resistance in plants are frequently clustered in the genome. Genes for resistance (R genes) to diverse pathogens cloned from several species encode proteins that have motifs in common. These motifs indicate that R genes are part of signal-transduction systems. Most of these R genes encode a leucine-rich repeat (LRR) region. Sequences encoding putative solvent-exposed residues in this region are hypervariable and have elevated ratios of nonsynonymous to synonymous substitutions; this suggests that they have evolved to detect variation in pathogen-derived ligands. Generation of new resistance specificities previously had been thought to involve frequent unequal crossing-over and gene conversions. However, comparisons between resistance haplotypes reveal that orthologs are more similar than paralogs implying a low rate of sequence homogenization from unequal crossing-over and gene conversion. We propose a new model adapted and expanded from one proposed for the evolution of vertebrate major histocompatibility complex and immunoglobulin gene families. Our model emphasizes divergent selection acting on arrays of solvent-exposed residues in the LRR resulting in evolution of individual R genes within a haplotype. Intergenic unequal crossing-over and gene conversions are important but are not the primary mechanisms generating variation.  相似文献   
858.
Hearing aids with multi-channel compression are often fitted on the basis of loudness scaling data obtained using narrow bands of noise or tones. Here, we report the development and evaluation of an alternative fitting procedure based on the use of speech signals. The parameters of the hearing aid (the gains in each channel for high and low input levels) are adjusted adaptively under computer control on the basis of the listener's responses. The goal is that speech at 85 dB SPL should be judged as 'loud', speech at 60 dB SPL should be judged as 'quiet', and speech at both levels should be judged as 'neither tinny nor boomy'. The procedure was evaluated using a two-channel compression hearing aid, the remote control of which allowed two programs to be stored. One program was based on our fitting procedure. The other was either based on the manufacturer's recommended full fitting procedure (which included loudness scaling with bands of noise), or was based on the audiogram alone, using the manufacturer's algorithm. After an acclimatization period of at least two weeks, subjects were then asked to fill in a questionnaire about their experiences with the two programs in different listening situations. The results generally indicated a preference for the program based on our adaptive fitting procedure. We also conducted laboratory measurements of speech intelligibility, in quiet and in a background of a single competing talker. These showed no clear difference between programs, although scores overall were very high. We conclude that our adaptive procedure gives very satisfactory results in everyday life. Parameter values giving good comfort also give good intelligibility. The procedure typically takes between five and 10 minutes per ear, which is quicker than most loudness scaling procedures.  相似文献   
859.
O'nyong-nyong (ONN) virus is an alphavirus (family Togaviridae, genus Alphavirus) classified in the Semliki Forest virus (SFV) antigenic complex. ONN was initially isolated in northern Uganda in 1959 during the early stages of an explosive arbovirus epidemic in which > 2 million cases were reported. No additional epidemics or human isolations of ONN were reported until 1996, when it was isolated from an epidemic in southern Uganda. We report the complete nucleotide and deduced amino acid sequence of one of these 1996-1997 ONN isolates (SG650) and that of the related alphavirus Igbo Ora virus. The data indicate that the recent ONN virus isolate is closely related to the previously published ONN strain isolated in 1959. In addition, phylogenetic analysis of the sequence data reveals that Igbo Ora virus, previously thought to be a separate virus closely related to ONN and Chikungunya (CHIK), clearly is a strain of ONN. The sequence data also reveal that unlike the published ONN (1959) sequence, all ONN strains from the 1996-1997 epidemic possess a stop codon at the nsp3-nsp4 junction.  相似文献   
860.
Transcarboxylase from Propionibacterium shermanii is a biotin-containing enzyme which catalyzes the reversible transfer of a carboxyl group from methylmalonyl-CoA to pyruvate. The central hexameric 12 S subunit of the enzyme associates with six 6 S subunits in the complete enzyme complex. We have constructed a series of cloned genes which encode COOH-terminal truncations of the 12 S subunit. Five of these subunits, which remained soluble following expression in Escherichia coli and were missing from 39 to 97 COOH-terminal amino acids, were purified and compared to the full-length subunit after enzyme complexes were assembled in vitro. All of the truncated subunits were 90% as active in the transcarboxylase reaction as wild type except the reaction containing the shortest complex, TC-12 S (1-507), which had 54% of the wild type activity (TC-12 S-WT). The reduced activity was not due to a lack of CoA ester binding sites or the Km for substrate. However, TC-12 S (1-507) was slower to form than TC-12 S-WT and had more incomplete complexes as judged by high performance liquid chromatography gel filtration profiles and electron microscopy. Isolated TC-12 S (1-507) was 70-80% as active as TC-12 S-WT. We also noted that the truncated form was heat-labile compared to wild type. We conclude that the COOH-terminal region of the 12 S subunit plays a role in assembly and stability of the hexamer and also affects the binding of 6 S subunits to form enzyme complexes. Once complexes do form, the catalytic capacity of TC-12 S (1-507) is almost the same as TC-12 S-WT.  相似文献   
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