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951.
The effect of thymosin fraction 5 and its synthetic component thymosin-alpha 1 administered i. p. and i. c. v. on the behavior of 219 Wistar rats in the open field was studied to establish the effective dose and time of action of both substances. It was shown that at i. c. v. administration of both compounds in a dose of 10 ng the motor activity was suppressed for about 0.5 hour. At i. p. administration thymosin fraction 5 in doses of 0.15, 0.3 and 0.6 mg/kg suppressed the motor activity for more than 2 hours. The higher the dose, the greater the degree of suppression of the motor activity. Both peptides influence in a similar way the motor activity of the animals irrespective of the route of administration.  相似文献   
952.
Experiments were performed on spinalized rats, transected at the Cl level. The intravenous administration of TRH and its analog YM-14673 (N alpha-[(S)-4-oxo-2-azetidinyl) carbonyl]-L-histidyl-L-prolinamide dehydrate) produced marked increases in the amplitude of mono- and polysynaptic reflex potentials and those of the withdrawal flexor reflexes. The effects of YM-14673 were stronger and longer-lasting than those of TRH. The stimulant action of TRH and YM-14673 on the flexor reflexes was not antagonized by prazosin, chlorpromazine, haloperidol or cyproheptadine, suggesting no involvement of the release of catecholamines or serotonin in the stimulant effects of TRH and its analog. Therefore, YM-14673 may be beneficial for the treatment of several spinal motor neuron diseases.  相似文献   
953.
Fifty-six patients with recurrent bronchopulmonary infections associated with chronic bronchitis were randomly allocated to 2 groups, to assess whether treatment with an immunomodulator, Diribiotin CK, could enhance resistance to infection. The double-blind, placebo-controlled prospective trial over a 9 month period showed that this immunomodulator was well tolerated and significantly reduced the rate of respiratory tract infection. The drug also significantly reduced the prescribing of antibiotic medication and the rate of absenteism from work. These effects have been demonstrated in a rigorously designed clinical study. This is the first time that a clear clinical activity has been attributed to an inducer of soluble mediators of immunity.  相似文献   
954.
955.
To determine the potential effect of screening on referral patterns, an adult population sample (4,404 men, 5,164 women, 20-69 years of age) was systematically recruited and screened for hypercholesterolemia and then analyzed by different cholesterol referral recommendations. Using levels suggested by the Lipid Research Clinics Coronary Primary Prevention Trial (greater than or equal to 265 mg/dL), 7.3% of men and 5.8% of women would be referred for follow-up. With the suggested recommendations of the National Cholesterol Education Program (NCEP), (greater than or equal to 200 mg/dL), 49.2% of men and 40.2% of women would be referred. The use of age-related definitions of the NIH Consensus Conference on Lipid Lowering results in 28.0% referrals in men and 21.8% in women. From this population, hypercholesterolemia subjects (greater than or equal to 265 mg/dL at screening; n = 624) were invited for a second cholesterol determination (58% returned), which found 36% below the 265 mg/dL level. Population screening for cholesterol is likely to produce large numbers of patients for follow-up, with the actual numbers strongly dependent on cutoff levels and age-sex distributions. Referral and follow-up of these patients may place a significant load on an unprepared health care community.  相似文献   
956.
The effect of psychosocial factors on lung cancer mortality at one year   总被引:1,自引:0,他引:1  
In this study newly diagnosed male and female lung cancer patients admitted to two Ontario Cancer Foundation treatment clinics were interviewed. Information was obtained on demographic variables, presence of other chronic illness and the following psychosocial attributes: locus of control, social support and personality traits. From the clinic charts, information on stage of disease and pathological diagnosis was obtained. After controlling for the effects of stage and pathological diagnosis, the following psychological variables were found to increase the odds of death from lung cancer among males and females combined at one year after diagnosis: a high need for one aspect of social support, a reserved personality and the extremes of the personality trait soberness vs enthusiasm.  相似文献   
957.
Ticks of the Ornithodoros moubata complex were collected from domestic pig sties and dwelling houses, and from a warthog habitat, and tested for the presence of African swine fever (ASF) virus. Collections were made in 9 of the 24 districts of Malawi, these being primarily the districts in which O. moubata is most numerous. ASF virus was isolated from ticks collected in both domestic pig sties and houses in certain villages in Mchinji district where ASF outbreaks had recently occurred. Mchinji district is in the centre of a large ASF enzootic area which stretches into other districts of Malawi and also into Zambia and Mozambique. The high titre of virus in some of the ticks demonstrates that O. moubata can act as a virus reservoir and potential vector of disease in the field situation in Malawi.  相似文献   
958.
959.
960.
Since its introduction in early 1985, the Volk +90D lens has become a very popular auxiliary lens for biomicroscopic fundus evaluation. The Volk +90D lens provides a wide field of view which is accessible by simple scanning of the biomicroscope. The necessity to hand hold the lens, however, has not always provided enough stability, particularly for the novice user. This article describes a newly introduced holder for the Volk +90D lens which mounts on the base of the biomicroscope headrest providing rapid and stable lens placement. Use of this holder improves the technique of retinal examination and photography by stabilizing the image and by freeing both hands to operate the slit lamp biomicroscope. The enhanced stability afforded by this holder also gives the examiner the practical capability of viewing the posterior pole without mydriasis.  相似文献   
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