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The neurotoxic effects of single subcutaneous injections of1000 mg triphenyl phosphite (TPP)/kg body weight were investigatedin White Leghorn hens. At 7 days postexposure, birds began toshow signs of mild to moderate ataxia that progressed to severeataxia and paralysis at 21 days. Inhibition of whole brain neuropathytarget esterase was 85% at 48 hr and 73% by 21 days postexposure.After postexposure periods of 7, 14, and 21 days, hens werekilled and their brains and spinal cords were examined for degeneratingaxons and terminals using the Fink-Heimer silver impregnationmethod. A small amount of degeneration was noted at 7 days.By 21 days, dense degeneration was noted in the spinal graymatter and funiculi. Degeneration was also present in the granularcell layer of cerebellar folia I-VI and in nuclei and fibertracts of the medulla. Moderate to dense degeneration was alsoseen in several forebrain and midbrain areas including the paleostriatum,ansa lenticularis, the dorsointermediate thalamic nucleus, lateralspiriform, pedunculopontine tegmental, and lateral mesencephalicnuclei and in the deeper layers of the optic tectum. These resultsindicate that, in addition to affecting the spinal cord andbrainstem, exposure to TPP also damages higher order centersresponsible for processing and integrating sensorimotor, visual,and auditory information. 相似文献
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Ohne Zusammenfassung 相似文献
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KLEPP K-I.; ULVIK R.J.; MATTHIESEN S.B.; HANNAN P.; JACOBS D.R. JR.; AARO L.E. 《European journal of public health》1993,3(1):38-42
The general public of the City of Bergen, Norway was Invitedto participate in a cholesterol screening programme in October1988. Participants received the results of the cholesterol screeningand nutritional information from trained health personnel. Ashort questionnaire was mailed to all 354 participants 12weeks after the initial cholesterol screening. In March 1990,all participants were invited to have their cholesterol levelsre-examined. Psychosocial factors believed to be predictiveof future serum cholesterol changes were assessed at baselinealong with demographic variables. The majority of participants(61%) reduced their cholesterol level from October 1988 to March1990, and the average reduction in cholesterol level for thetotal population was 4.0%. Baseline cholesterol levels, beingconfident of one's own ability to change one's diet (self-efficacy),seeing heart disease risk reduction as very important, and maritalstatus were factors that significantly predicted successfulcholesterol reduction 18 months later. 相似文献
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Postoperative radiation therapy in the management of lung cancer 总被引:1,自引:0,他引:1
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate. 相似文献
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Evaluation of maternal plasma creatine kinase activity as a marker of abnormal early pregnancy 总被引:1,自引:0,他引:1
Zorn JR; Cherruau B; Abi-Rached F; Dehee A; Danoy X; Le Blond J; Ekindjian O 《Human reproduction (Oxford, England)》1997,12(11):2534-2537
We have tested the value of maternal plasma creatine kinase activity for
diagnosing ectopic pregnancies obtained after in-vitro fertilization and
embryo transfer. Plasma creatine kinase was assayed in 57 patients: 20
normal, 23 miscarriages and 14 ectopic pregnancies, for a total of 240
samples. All values were in the lower part of the normal range except only
one in a miscarrying patient. A statistically significant difference was
observed for a cut-off value of 45 IU/l between normal and ectopic
pregnancies. However, for this cut-off point, the measurement of plasma
creatine kinase activity had a sensitivity of 0.50 and a specificity of
0.76 for the diagnosis of ectopic pregnancy. The positive predictive value
was 0.69. Creatine kinase activity measurements are thus of no practical
value in this particular population, in which an early and specific marker
of ectopic implantation would be of paramount interest. The association of
human chorionic gonadotrophin (HCG) determinations and ultrasound scanning
of the pelvis still remain the best paraclinical support for an early
diagnosis of ectopic implantation.
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