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991.
Male Sprague-Dawley rats injected (i.p.) at 1500h with L-acetyl-carnitine in doses of 10, 30 or 90 mg/kg exhibited a notable increase in their pineal and serum melatonin content 1 hr later. Likewise, L-acetyl-carnitine administered in the same dose range induced a significant increase of pineal and serum melatonin content in rats treated at 0100h, following exposure of 30 min to bright white light to suppress endogenous melatonin. Under in vitro experimental conditions, however, 60 min of coincubation of isolated rat pineal glands with L-acetyl-carnitine (10(-5) M) did not result in an elevation in melatonin accumulated in the incubation medium. These results demonstrate that, in vivo, L-acetyl-carnitine can exert a modulatory action on synthesis and release of melatonin, possibly by modifying noradrenergic transmission and signal transduction in the pineal gland.  相似文献   
992.
Individuals who undergo head and neck surgery experience extreme stressors that go beyond those which occur with the usual surgical patient. This paper will review the literature and discuss the psychiatric consequences of otolaryngeal surgery. In addition, new head and neck surgical techniques, which offer special challenges to the patient as well as to the psychiatric consultant, will be examined. Tracheostomy, which occurs as a result of head and neck surgery, is of particular importance with regard to postoperative adaptation and is a significant complication that must be reckoned with.  相似文献   
993.
Summary Stress-induced hyperthermia (SIH), which is seen in the last mice removed from the cage, is a novel animal model sensitive to anxiolytic drugs. SIH is antagonized by CL 218872 (25 and 50 mg/kg, os), by tracazolate (5 and 7.5 mg/kg, ip) and by 2-AP-5 (50 and 100 mg/kg, ip). At higher dose, CL 218872 (100 mg/kg, os) and tracazolate (12.5 mg/kg, ip) lose their activity.PK 9084 (5–40 mg/kg, ip) and CGS 9896 (2–20 mg/kg, both ip and os) were also ineffective in preventing SIH. The anti-hyperthermic effect of CL 218872 (25 mg/kg) and tracazolate (7.5 mg/kg) was blocked by the benzodiazepine antagonist Ro 15–1788 (15 mg/kg). CGS 9896 (10 mg/kg, os) also reversed the effect of CL 218872 (25 mg/kg) on SIH.Differently from anxiolytics, MK-801 (0.5–1 mg/kg, os), PCP (2.5 mg/kg, ip) and d-amphetamine (10 mg/kg, ip) evoked hyperthermia in the first set of mice and prevented a further stress-induced rise of body temperature in the last set of mice.  相似文献   
994.
A modified method for measuring vitamin E is described, making use of thin-layer chromatography with Silufol plates. Effects of various storage conditions of the blood serum on its vitamin E levels were examined. Vitamin E proved to be sufficiently stable at storage at -10 degrees C and defrosting under 20 degrees C. Comparison of this mode of storage with other ones has demonstrated its advantages. The method was tried in clinical practice in examinations of patients with pulmonary tuberculosis, chronic alcoholism, females suffering from infertility due to inflammations and healthy ones (controls) and found to be accurate, reproducible, and informative.  相似文献   
995.
Analytic, within-subject, and between-subject biologic variations were estimated for leukocytes, erythrocytes, hemoglobin, hematocrit, mean cell volume (MCV), mean cell hemoglobin (MCH), mean cell hemoglobin content (MCHC), platelets, and a three-component differential count (lymphocytes, monocytes, and granulocytes in terms of both concentration and percentage of leukocytes) in cohorts of 12 male and 12 female healthy elderly subjects. The assays were performed with an Ortho ELT-800 automated analyzer. The estimates of within-subject biologic variation were similar to published data on young subjects, indicating that this aspect of homeostasis is not compromised in the elderly. The data were used to derive objective analytic goals; goals were surpassed except for assays of erythrocytes, hematocrit, and the derived MCV, MCH, and MCHC. The changes required for serial results to be significantly different were determined and found to be generally valid because most quantities have no heterogeneity of within-subject variation. All quantities had significant individuality; in consequence, conventional population-based reference values are of limited utility, and screening using reference limits will not detect latent or early disease in many subjects.  相似文献   
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997.
The study concerns symptoms and behavioral characteristics induced by MPTP in a 20-year-old Macaca cynomolgus fascicularis, their evolution over 7 months, and the animal's response to 1-dopa treatment. The symptoms which the animal developed include those that have been described earlier in Macaca mulatta and Saimiri sciureus, i.e., rigidity, action tremor, postural tremor, postural flexion, hypokinesia, and bradykinesia. In addition, however, the animal developed a 3.8 Hz resting tremor which in humans is pathognomonic of Parkinson's disease, as well as cogwheeling, the glabellar tap sign, drooling, impaired ability to relax, and many other symptoms. Also unlike previously described MPTP monkeys, the animal's symptoms neither improved spontaneously, nor did they remain stable shortly after MPTP injection. Instead, symptoms steadily progressed to reach a severe status 2 months after MPTP, and further progression was apparent after another 5 months. Therapeutic responses to 1-dopa required accumulation of or kindling by the 100 mg unit doses that were spaced 4 hr apart, were often organized in time as ON episodes that alternated with OFF episodes, and were associated with dyskinesias and bizarre behavior. Of particular interest is that the animal showed kinesia paradoxa which, in humans, constitutes a feature that is unique to Parkinson's disease among the extrapyramidal disorders. In addition to available evidence, the present findings validate the syndrome induced by MPTP in monkey as an animal analogue of Parkinson's disease. Taxonomic category, age, and the occurrence of shock in response to MPTP are discussed as variables that may possibly co-determine the pathology which MPTP may induce in monkey.  相似文献   
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