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991.
AP Pobegailo 《Computer aided design》1996,28(12):973-979
This paper presents a method for Cn interpolation on smooth manifolds by performing one-parameter transformations on them. Continuity of interpolating curves is achieved by smooth transitions between the transformations. Interpolating curves have local control. Constructing of curves on quadrics, SO(3, R) and GL(3, R) is considered. 相似文献
992.
AP Halestrap 《Canadian Metallurgical Quarterly》1976,156(1):181-183
Pyruvate transport into rat liver mitochondria is inhibited by a variety of thiol reagents. alpha-Cyanocinnamate and its derivates, potent and reversible inhibitors of pyruvate transport, react reversibly with mercaptoethanol and cysteine to form addition products. It is concluded that these inhibitors react with an essential thiol group on the pyruvate carrier. 相似文献
993.
Prolonged isolation of rats resulted in hyperactivity in the open field and a significant increase in 24 hr urinary excretion of MHPG (3-methoxy-4-hydroxyphenylglycol). Exploratory activity of group-housed rats in open field was not associated with raised MHPG excretion, compared with that of rats remaining in home cages. Exposure of group-housed rats to 4 degrees C for 2 hr also increased urinary excretion of MHPG. Pretreatment of isolated rats with dl-, d-propranolol or practolol abolished hyperactivity of isolated rats and reduced MHPG output in these rats and in rats exposed to cold. dl-Propranolol did not reduce activity of group-housed rats in open field or their urinary excretion of MHPG. It is suggested that propranolol may have a selective inhibitory effect on stress-induced increases in noradrenaline turnover. 相似文献
994.
The effect of a brief appointment reminder for mental-health center applicants is reported. A standardized phone message was delivered by an administrative staff member one to three days before the appointment and a sequential experimental design alternating baseline and phone message conditions was used to assess the effects of the procedure. The no-show rate averages were 32%, 11%, 25%, and 14% respectively. The cost of the procedure was $162.00, which was totally recovered when only six appointments were kept. Since over 1000 patients were involved in the study, the return on the investment of +162.00 is considerable. Implications for this procedure are discussed for other community mental-health centers and for other community care-giving agencies. 相似文献
995.
In well-fed normal male rats, either force-feeding of tryptophan or a single injection of phenobarbital produced significant increments in hepatic microsomal cytochrome P-450 and the associated aniline hydroxylase activity. Administration of both tryptophan and phenobarbital together resulted in even greater stimulation than when the compounds were given alone. Adrenalectomy lowered instead the cytochrome P-450 concentration in comparison with that of normal rats, and administration of tryptophan and phenobarbital in this condition produced no significant increment in cytochrome P-450 concentration. In addition, phenobarbital administered either singly or in combination with tryptophan resulted in 80% mortality, which was reduced to zero by pretreatment with cortisol. While in cortisol-treated adrenalectomized rats administration of phenobarbital caused a 56% increment in cytochrome P-450 as compared to controls, tryptophan produced only a minor (9%) increase. In normal, as well as in adrenalectomized rats, tryptophan and phenobarbital administered either idividually or together increased microsomal protein concentration. In normal rats actinomycin-D treatment reduced both cytochrome P-450 and microsomal protein concentrations below that of the non-treated control levels. Further administration of either tryptophan or phenobarbital slightly increased the level of cytochrome P-450, and the two compounds together caused 40 and 21% increments of the same compared to actinomycin-treated and non-treated controls, respectively. 相似文献
996.
Efficacy of different feeding levels of monensin in the control of coccidiosis in broilers 总被引:1,自引:0,他引:1
The feed level of monensin which gave maximal protection from coccidial infection in broilers reared in floor pens depended on the severity of the coccidial exposure and the criteria of infection studied. With indirect seeding of pens with coccidia (light coccidial exposure), 40 ppm was as efficacious as 100 ppm in improving weight gain, lesion score, and feed conversion. Statistical analysis with direct seeding (seeder birds; severe coccidial exposure) showed that feed levels of 84 and 102 ppm gave maximal improvement of weight gain and 4-week feed conversion, respectively. Further increasing the monensin level from 100 to 121 ppm did not improve weight gain and feed conversion at 8 weeks. Conversely, the relationship of plasma pigmentation and total lesion scores to monensin feed levels indicated that increasing the dosage of monensin from 100 to 121 ppm improved the performance of the broilers on the basis of these 2 infection indicators. 相似文献
997.
Branching patterns of single corticospinal (CS) neurons were studied in the cat by activating these neurons antidromically from various regions of the spinal cord. 1. One hundred and ninety-three neurons were activated antidromically by microstimulation in the gray substance of the cervical cord and the majority of them were found in the forelimb area of the pericruciate cortex. 2. Branches to the lower levels of the spinal cord were found for 30% of the neurons projecting to the cervical gray matter. 3. The remaining 70% sent axons only to the cervical gray matter and some of them sent multiple branches to several segments in the cervical cord. 4. Only a few CS neurons located outside of the forelimb area could be activated from the cervical cord, but all of them also sent branches to the lower levels of the spinal cord. Neurons projecting to both the cervical cord and the lower levels were intermingled in the cortex with those projecting only to the cervical cord. 5. CS neurons activated from a given area of the cervical cord were often clustered together in a small area of the cortex, although some of these CS neurons sent their other branches to other parts of the spinal cord and neurons projecting to other parts were also intermingled among them. 6. The functional significance of multiple axonal branching of CS neurons is discussed in relation to cortical motor functions. 相似文献
998.
999.
Peripherally harvested lymphocytes have been labelled with 51Cr, reinjected into human subjects and their distribution then studied. Evidence is presented which suggests faecal loss of 51Cr represents loss of T lymphocytes and that there is normally a pathway of lymphocyte removal into the gut of probable importance in lymphocyte migration streams. In 9 normal subjects, without structural intestinal disease, faecal loss of lymphocytes over 5 days was 0.20% (SEM +/- 0.06) whereas in 5 patients with untreated coeliac disease faecal loss was 1.13 +/- 0.34%, in 7 with Crohn's disease it was 1.01 +/- 0.21% and in 5 with intestinal lymphangiectasia loss was 0.61 +/- 0.10%. In 1 patient with acute tropical sprue, enteric loss was 0.97%. By contrast, faecal loss was normal in 3 coeliac patients in remission on a gluten-free diet. Measurements were also made using an external counter. In contrast to the normals, where count rates steadily diminished, an increasing activity was recorded over the umbilicus over 7 days after dose administration in all the disease categories studied with the exception of the treated coeliacs. The finding of an increased enteric loss of lymphocytes may explain many of the immunological abnormalities in the conditions studied. 相似文献
1000.
本文介绍了如何用SystemVerilog验证FPGA,从而说明采用现有的验证工具和方法可以提高设计质量,并加快产品上市速度. 相似文献