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991.
LIa Mel'nichenko II Sheleketina LP Averianova SS Iagmur 《Canadian Metallurgical Quarterly》1997,(6):53-56
Our studies on phosphatide, a food concentrate, produced as a by-product during the extraction of an edible oil in the oil-extraction plants, showed its high efficacy in patients (n = 52) with abnormalities of the hepatobiliary system. The drug having more than 40 weight percent of phosphorus-containing lipids appeared to be efficacious not only in respect of the subjective status of the patients but also the functional state of the liver and paraments characterizing lipid metabolism. 相似文献
992.
OBJECTIVE: To determine if the use of a catheter-valve rather than a standard drainage system decreases the morbidity associated with the use of a long-term catheter. PATIENTS AND METHODS: One hundred patients undergoing long-term catheterization were recruited into a prospective randomized study to investigate the acceptability and determine any increase in infection associated with the use of a catheter-valve, compared with the standard drainage system. Each patient participated in the study protocol for 3 months, during which the frequency of urinary tract infection was assessed, and the patients' views obtained using a standard questionnaire and by interview. RESULTS: Ninety-four patients completed the study; most (92%) were happy or satisfied with the valve, as opposed to only 35% of those using a standard drainage bag. There was no significant difference between the groups in the incidence of urinary tract infections. CONCLUSION: The patients who used the standard drainage system felt their level of activity was impaired, whereas the group who were using the valve did not. In the long-term the valve was cheaper and caused less morbidity, but because it is constructed to allow one-way flow, this was not associated with an increase in the incidence of urinary tract infections. 相似文献
993.
994.
The lpxC (envA) gene of Escherichia coli encodes UDP-3-O-acyl-GlcNAc deacetylase, the second and committed step of lipopolysaccharide biosynthesis. Although present in all gram-negative bacteria examined, the deacetylase from E. coli is the only example of this enzyme that has been expressed and purified. In order to examine other variants of this protein, we cloned the Pseudomonas aeruginosa deacetylase structural gene from a lambda library as a 5.1-kb EcoRI fragment. The LpxC reading frame encodes an inferred protein of 33,435 Da that is highly homologous to the E. coli protein and that possesses a nearly identical hydropathy profile. In order to verify function, we subcloned the P. aeruginosa lpxC gene into the T7-based expression vector pET11a. Upon induction at 30 degrees C, this construct yielded active protein to approximately 18% of the soluble fraction. We devised a novel, rapid, and reproducible assay for the deacetylase which facilitated purification of the enzyme in three steps. The purified recombinant protein was found to be highly sensitive to EDTA yet was reactivated by the addition of excess heavy metal, as was the case for crude extracts of P. aeruginosa. In contrast, deacetylase activity in crude extracts of E. coli was insensitive to EDTA, and the extracts of the envA1 mutant were sensitive in a time-dependent manner. The lpxC gene has no significant homology with amidase signature sequences. Therefore, we assign this protein to the metalloamidase family as a member with a novel structure. 相似文献
995.
996.
EJ Hoffenberg SS Rothenberg D Bensard JM Sondheimer RJ Sokol 《Canadian Metallurgical Quarterly》1997,151(10):993-998
BACKGROUND: Abdominal pain in childhood is common yet frustrating when unexplained. OBJECTIVE: To describe the clinical features and outcome of 8 children (6 girls and 2 boys; mean[+/- SD] age, 13 +/- 2 years) with unexplained abdominal pain who underwent exploratory laparoscopy. SETTING: All 8 patients were examined at an academic pediatric gastroenterology center and referred for exploratory laparoscopy because of unexplained abdominal pain. Laparoscopy was offered after family agreement to pursue behavioral management if the pain and disability did not improve. RESULTS: In all 8 children, laparoscopy detected an anomaly at a site corresponding to that of the abdominal pain. Findings were adhesions in 7 children (3 colonic, 2 ileocecal, 1 gastric, and 1 appendiceal) and ovarian torsion in 1 child. At a mean follow-up of 12.6 months, the abdominal pain had completely resolved in 6 children, notably improved in 1 child, and continued unchanged in 1 child. Disability completely resolved in 2 of 3 children. CONCLUSIONS: In children with unexplained abdominal pain that is acute in onset, well described, and suggestive of peritoneal involvement, exploratory laparoscopy (1) successfully ends the cycle of abdominal pain in most cases; and (2) commonly identifies abnormalities, usually adhesions. However, whether laparoscopy, the placebo effect, or both promote the healing process is unclear. Further study is needed to develop criteria for referral for laparoscopic evaluation of unexplained abdominal pain. 相似文献
997.
S Das SW Barthold SS Giles RR Montgomery SR Telford E Fikrig 《Canadian Metallurgical Quarterly》1997,99(5):987-995
The temporal synthesis of the P21 protein of Borrelia burgdorferi and the development of the humoral response to this antigen was assessed in infected mice. p21 is a member of the ospE-F gene family and its protein, P21, has been shown to be expressed by B. burgdorferi within infected mice but not by spirochetes cultured in vitro. P21 was not detected on B. burgdorferi in unfed or engorged Ixodes dammini (also known as I. scapularis) ticks, further supporting the postulate that P21 synthesis is specific for the mammalian host. In B. burgdorferi-infected mice, ospE mRNA and OspE antibodies were observed at 7 d, whereas p21 mRNA and P21-specific antibodies were detected at 21-28 d, suggesting that p21 is expressed later than ospE. Moreover, ospA mRNA was not discernible until day 14, indicating that ospA, like p21, is not expressed in the early stages of tick-transmitted murine Lyme borreliosis. Because p21 is expressed during infection in mice, we assessed the human humoral response to P21. 28% (34 of 122) of the patients with either early- or late-stage Lyme disease, and 33% (11 of 33) of the individuals with Lyme arthritis had P21 antibodies, suggesting that a P21 response may serve, at least partially, as a marker of infection. Active immunization with recombinant P21 did not protect C3H mice from tick-borne B. burgdorferi infection, and passive transfer of P21 antiserum to infected mice did not alter the course of disease. These data suggest that the antigenic structure of B. burgdorferi changes during the early stages of murine infection. 相似文献
998.
999.
1000.
A Abi-Dargham MS Gandelman GA DeErausquin Y Zea-Ponce SS Zoghbi RM Baldwin M Laruelle DS Charney PB Hoffer JL Neumeyer RB Innis 《Canadian Metallurgical Quarterly》1996,37(7):1129-1133
Iodine-123-2 beta-carbomethoxy-3 beta-(4-iodophenyl)tropane (beta-CIT) is a useful SPECT tracer for imaging the dopamine transporter. Its slow kinetics, however, necessitate imaging on the day after the injection. Two N-omega-fluoroalkyl analogs of beta-CIT, the fluoropropyl and fluoroethyl compounds (beta-CIT-FP and beta-CIT-FE, respectively), characterized by faster kinetics in baboons, were tested in humans as potential tracers for the dopamine transporter. Four healthy volunteers were injected with [123I]-beta-CIT-FP and another four were injected with [123I]beta-CIT-FE. SPECT data were acquired for 1149 +/- 590 min and 240 +/- 30 min, respectively. Both tracers demonstrated high brain uptake (6.37% +/- 0.37% and 7.8% +/- 1.5% of the injected dose, respectively). Activity concentrated with time in the striatal area, reaching a peak within 30 min, with little or no washout for [123I]beta-CIT-FP and a faster washout for [123I]beta-CIT-FE (14.7% +/- 6.9%). Occipital and midbrain activity showed similar patterns, displaying a peak within 15 min and rapid washout, followed by stable levels at approximately 100 min for both tracers. The ratio of peak specific striatal-to-peak specific midbrain activity was 9.1 +/- 1.8 for [123I]beta-CIT-FP and 7.7 +/- 0.7 for [123I]beta-CIT-FE, showing high in vivo selectivity for the dopamine transporter. These preliminary results suggest that both compounds could be used as SPECT (labeled with 123I) or PET (labeled with 18F) radiotracers to image the dopamine transporters in the living human brain. 相似文献