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41.
Twenty healthy men and twelve patients with hypertensive type neurocirculatory dystonia belonging to the flying personnel were examined. They breathed a hypercapnic-hypoxia mixture formed during rebreathing in a closed circuit without a CO2 adsorber. In both groups this provocative test produced similar variations of most parameters under study. However in contrast to the healthy men, the hypertensive subjects showed a lower compensatory hyperventilation, a greater increase of blood pressure and cardiac output and a relatively small decrease of total peripheral resistance. Three test subjects displayed sinus arrhythmia. The time of test tolerance in the patients was on the average 20% shorter than in the healthy subjects. The changes can be viewed as an indication that the reserve capability of the cardiorespiratory system declines. The fact that the test is rapid, simple and safe makes it possible to use it during regular medical monitoring of the flying personnel with functional disorders of the cardiovascular system.  相似文献   
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Types of ophthalmic traumas subject to change at present are enumerated: communal, criminal, war traumas, and injuries resultant from emergency situations (disasters). The changes are discussed. Main factors which should be borne in mind when investigating the problem of ocular injuries are determined. Priority trends of research in ophthalmic traumatology are defined.  相似文献   
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Interferon was injected intracervically as the first stage of combination treatment in 125 cases of histologically verified squamous Ca in situ and invasive cervical carcinoma. Colpomicroscopic, cytological and histological examination was carried out before and after treatment. The pronounced effect of interferon as an antitumor agent was established. Post-treatment histological examination failed to detect any tumor cells in 36 out of 125 patients (28.8%). Widening the scope of indications for preservative operations in patients with preinvasive and microinvasive cervical carcinoma after preliminary interferon therapy was suggested.  相似文献   
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MRI scans were obtained of the cervical section of the spinal cords of 30 patients with remitting multiple sclerosis. During the study period, patients received immunomodulatory agents (seven received interferon β-1a, 13 received interferon β-1b, and 10 received glatiramer acetate). Total focus volume in brain matter was assessed before and after treatment, along with the linear size of the spinal cord on sagittal sections at the level of the inferior margin of the body of C2. There was a significant (p = 0.002) reduction in focus volume in the group overall, from 10993 mm3 (8098–13888 mm3, p < 0.05; Me = 9336) to 5630 mm3 (7400–3860 mm3, p < 0.05, Me = 4180). There were also significant decreases in focus volume on the background of treatment with interferon β-1b and glatiramer acetate (p = 0.026 and 0.027, respectively). Significant differences between groups were found in the magnitudes of increases in spinal cord atrophy: H (2, n = 30) = 8.06; p = 0.0178. Patients given glatiramer acetate showed a significantly smaller increase in atrophy as compared with those treated with interferon β (p < 0.02). Translated from Zhurnal Nevrologii i Psikhiatrii imeni S. S. Korsakova, Multiple Sclerosis, Supplement, No. 4, pp. 129–132, 2007.  相似文献   
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Sex differences have been reported in a variety of affective and neurodegenerative disorders that involve dysfunctional dopamine (DA) neurotransmission. In addition, there is evidence for differences in sensitivity to the abuse-related effects of psychostimulants across the menstrual cycle which may result from effects of ovarian hormones on DA function. The goal of the present study was to extend previous work examining menstrual cycle-related changes in DA D2 receptor availability in humans to drug-naive female cynomolgus monkeys (n=7) using the selective D2-like receptor ligand [(18)F]fluoroclebopride (FCP) and a high-resolution microPET P4 scanner. Menstrual cycle phase was characterized by daily vaginal swabs and measurements of serum progesterone levels. PET studies were conducted once during the luteal phase and once during the follicular phase. Regions of interest in the caudate nucleus, putamen, and cerebellum were defined on coregistered MRIs. Distribution volumes were calculated for FCP in each structure and the distribution volume ratio (DVR) for both brain regions relative to the cerebellum was used as a measure of D2 receptor availability. FCP DVRs were significantly higher in the luteal phase compared to the follicular phase in both the caudate nucleus (11.7% difference, p=0.02) and putamen (11.6% difference, p=0.03). These findings extend earlier work in humans and suggest that changes in DA receptor availability may be involved in the variation in symptoms of various neuropsychiatric disorders across the menstrual cycle, including differences in sensitivity to the abuse-related effects of stimulants.  相似文献   
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BACKGROUND: The reason for increased peripheral blood leukocyte (PBL) nitric oxide (NO) production in patients with multiple sclerosis (MS) is unknown. OBJECTIVE: To investigate whether PBL NO production is related to measures of oxidative stress. METHODS: PBL nitrite, diene conjugates (DC, a measure of undergone oxidative stress), antiradical activity (ARA) and antioxidant acitvity (AOA) were measured in 35 healthy control persons and 80 patients with MS. We investigated the correlation of these measures with a partial correlation analysis, with age as the control variable. RESULTS: There was a significant correlation in both MS patients and healthy control persons between PBL nitrite levels and PBL DC, ARA and AOA. The correlations were stronger in healthy control persons. An analysis by disease subtype showed that the correlations were present in patients with relapsing-remitting and secondary progressive MS, but absent in primary progressive MS. CONCLUSIONS: PBL nitrite levels and measures of oxidative stress are closely related in MS-patients as well as in healthy control persons. Increased serum NO levels in MS may be the result of a physiologic reaction to overall oxidative stress. The differences in the strength of correlation between different disease subtypes may reflect differences in leukocyte biology.  相似文献   
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