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91.
The AA. investigated the frequency of antibodies against Toxoplasma gondii in 426 women with repeated abortions, perinatal mortality and malformed newborns. They showed on the whole a low incidence even if they demonstrated a high incidence (77.7%) of antibodies in women with malformed newborns. The meaning of the observations are briefly discussed. 相似文献
92.
Urinary metabolites and the pharmacokinetics of radioactivity derived from 14C-metronidazole (14C-MTZ) were determined after intravenous (iv) or intravaginal (ivg) administration of 10 mg/kg to adult rats. Following iv or ivg administration, the disappearance of 14C from blood followed the kinetics of a two-compartment open-system model. The blood half-lives of 14C during the beta-phase were 10.9 +/- 1.6 and 13.6 +/- 4.2 hr, after iv and ivg administration, respectively. After ivg application, the MTZ-derived radioactivity was detected in tail blood at 5 min, peaked at 1 hr, declined rapidly to 6 hr and more slowly thereafter. The vaginal absorption half-life of 14C-MTZ was 0.28 +/- 0.09 hr. About 12% of the administered dose remained in the vagina after 1 hr and 1.5% after 24 hr. At 24 hr, the tissue distribution and concentration of 14C were similar in iv and ivg dosed rats, the highest 14C concentration being present in the kidneys and lowest in the fat. The percentages of the dose excreted in 24 hr in the urine and feces were 58 and 15 after iv administration, compared to 37 and 40 after the ivg route, respectively. Unchanged 14C-MTZ and five of its metabolites were detected in the urine irrespective of the route of administration. The results show that metronidazole is rapidly absorbed through the vaginal mucosa of the rat and the metabolism and excretion of this chemotherapeutic agent are influenced by the route of administration. 相似文献
93.
94.
Copper speciation was determined in 68 rainwater samples collected in Wilmington, NC, from August 25, 2000, to September 24, 2002. Volume-weighted average concentrations of Cu(total), dissolved Cu(II), and dissolved Cu(I) were 5.3, 3.2, and 1.4 nM, respectively, with a significantly higher ratio of Cu(II)/Cu(I) in summer relative to winter events. The concentrations of all Cu species were higher in storms of continental origin relative to marine-dominated events, suggesting anthropogenic and/or terrestrial sources are important contributors of Cu in precipitation. Concentrations of strong Cu-complexing ligands were consistently lower than dissolved Cu concentrations, indicating a significant portion, but not all, of the dissolved Cu in rainwater is strongly complexed. A portion of these ligands, in addition to the sulfite and chloride in precipitation, may be Cu(I)-complexing ligands, which may explain the resistance of Cu(I) against oxidation in rainwater. Using our rainwater concentration data along with other published rainwater Cu concentrations and an estimate for total global annual rain, the total global flux of Cu removed from the atmosphere via wet deposition is 150 x 106 kg yr(-1). This represents complete removal of the estimated Cu input into the troposphere and indicates essentially all Cu released into the global atmosphere is removed by rain. 相似文献
95.
Cliff Saunders 《Accident; analysis and prevention》1980,12(1):75-76
96.
The effect of variation in dietary ascorbic acid on surgically induced osteoarthritis was examined in the stifle joints of guniea pigs. Two different surgical procedures were used to induce osteoarthritis in the right stifle joint of these animals. Guinea pigs were maintained either on a high (150 mg/day) or low (2.4 mg/day) dietary intake of vitamin C. Regardless of the surgical procedure used to induce osteoarthritis, the animals maintained on the high level of vitamin C consistently showed severe joint damage than animals on the low level of the vitamin. 相似文献
97.
CV Burton WH Kirkaldy-Willis K Yong-Hing KB Heithoff 《Canadian Metallurgical Quarterly》1981,(157):191-199
An interinstitutional study on the failed back surgery syndrome (FBSS) has determined that failure to recognize or adequately treat lateral stenosis of the lumbar spine with resultant nerve irritation and/or compression comprised the primary etiology in 57% to 58% of patients. Other common causes were recurrent or persistent disk herniation and lumbosacral adhesive arachnoiditis. The diagnosis of stenosis was made either by high-resolution CT scan of the lumbar spine or by directly testing lateral canal and for animal patency at the time of surgery. It is now appreciated that the process of degenerative disk disease, particularly when enhanced by diskectomy, results in progressive loss of intervertebral disk volume and predisposes to future ipsilateral or contralateral lateral spinal stenosis. Degenerative disk disease is ultimately a bilateral process and therefore surgical exposure should be bilateral. The direct and indirect costs of FBSS to patients and to society as well as the toll in human suffering are very high. This is particularly a matter of concern when it is realized that for many FBSS patients, surgery could have been avoided in the first place by preventive care or by innovative conservative treatment. When surgery is indicated, adequate diagnostic tests and the execution of appropriate procedures based upon this information should largely prevent the failed back surgery syndrome. 相似文献
98.
Dragline productin estimates, as derived from published tables, are compared to actual field production. Several equipment texts present dragline production estimating tables. The base data source for most of these tables are studies performed by the Power Crane and Shovel Association, PCSA. Only a small variance existed between the actual and estimated production. 相似文献
99.
BACKGROUND: Dehydroepiandrosterone (DHEA) is among the most abundant steroids in the human body and appears to have diverse biochemical activities. This multifunctional hormone has long been a compound of interest to research psychiatrists. Its recent promotion and availability as an over-the-counter supplement to the general public has led to widespread use. Little is known about potential adverse effects of DHEA when consumed on an acute or chronic basis. We report a case of mania in an older man acutely admitted to our psychiatric facility with no previous personal or family history of bipolar disorder that appeared to be related to recent DHEA use. The patient had initiated DHEA use 6 months prior to admission and was taking 200-300 mg/day at the time of presentation. METHODS: He was treated with valproic acid 500 mg twice daily. RESULTS: The patient showed sufficient improvement to be discharged following a 7-day inpatient hospitalization. CONCLUSIONS: A wide range of medications have been associated with the induction of hypomania and mania, and we have provided a brief discussion of the potential for DHEA to trigger manic symptoms. 相似文献
100.
P. J. Delaquis S. M. Ward R. A. Holley M. C. Cliff G. Mazza 《Journal of food science》1999,64(3):519-524
Pre-cooked roast beef slices were stored 28 days at 4±2°C in air or 100% N2 with and without vaporized horseradish essential oil (HEO). Addition of 20 μL HEO/L restricted growth of most spoilage bacteria. Pseudomonas spp. and Enterobacte-riaceae were strongly inhibited by HEO. Lactic acid bacteria were more resistant to the antimicrobial effect and dominated spoilage flora. Sensory evaluation and headspace analysis by gas chromatography/mass spectrometry revealed that development of off-flavors and odors derived from fat oxidation products was delayed by HEO. Cooked meat color was also preserved in samples stored under HEO. 相似文献