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991.
To clarify when and how rapidly individual muscles are damaged in the course of Duchenne muscular dystrophy (DMD), we followed X-ray CT of whole body skeletal muscles from 29 cases of DMD patients (age ranging 3 to 23 years) for a period of 2 to 6 years. Each patient had 2 to 5 scans with an average of 3.3. We evaluated chronological changes of 23 muscles from the entire body using the muscle damage stage defined as follows. The stages were classified into the following 5 stages: stage 0; normal, 1; area of fatty replacement less than 10% of whole muscle area, 2; area of fatty replacement between 10 to 50%, 3; area of fatty replacement 50 to 90%, 4; almost complete fatty replacement. Each muscle had its own period of rapid degeneration starting at 5 to 10 years of age and, continuing 5 to 10 years. In some muscles such as gluteus maximus or quadriceps femoris, fatty replacement started at 5 years or earlier and progressed for five years, while other muscles such as splenius capitis, damage started much later, e.g. around 10 years of age and the progression was much slower. There was a variation of at least 5 years among individual patients in any muscle damage stage, reflecting the variability of clinical severity in each patient. On the basis of the above results we defined the whole body muscle damage index as a summation of the muscle damage stages of the following five muscles: gluteus maximus, quadriceps femoris, gracilis, medial head of gastrocnemius and splenius capitis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
Evidence that dopamine in the nucleus accumbens is involved in the ability of rats to switch to cue-directed behaviours. 总被引:2,自引:0,他引:2
R van den Bos G A Charria Ortiz A C Bergmans A R Cools 《Behavioural brain research》1991,42(1):107-114
Recently we have reported that injections of d-amphetamine into the nucleus accumbens enhanced the number of switches to cue-directed behaviours without an effect on the number of switches to non-cue-directed behaviours in a swimming test. In the present study we investigated to what extent this effect is mediated via the dopaminergic system in the nucleus accumbens. For that purpose drugs selective for D1- and D2-receptors were studied in this swimming test. It was found that the selective D2-agonist LY 171 555 (50 ng/0.5 microliters) enhanced the number of different cue-directed behaviours. The selective D2-antagonist raclopride (50 ng/0.5 microliters) decreased it. Furthermore an ineffective dose of raclopride attenuated the effect of LY 171 555. Both the selective D1-antagonist SCH 23390 (400 ng/0.5 microliters) and the selective D1-agonist SKF 38393 (50-400 ng/0.5 microliters) decreased the number of different cue-directed behaviours. The effect induced by SCH 23390 could not be blocked by SKF 38393. Similarly the effect induced by SKF could not be attenuated by SCH 23390. These data point to a role for dopamine D2-receptors in the ability to switch to cue-directed behaviours. The present findings do not yet allow the conclusion that D1-receptors are involved. 相似文献
993.
A survey of hospitals in New York State treating psychiatric patients with chemical abuse disorders.
Eighty-eight of 143 hospitals in New York State providing psychiatric inpatient treatment responded to a mailed questionnaire designed to determine the size of three subgroups of chemical abusers--alcohol abusers, drug abusers, and polychemical abusers--among inpatients with psychiatric diagnoses, as well as the availability of services for these patients. Data for New York City and its metropolitan area were analyzed separately. In 1987 almost one-third of psychiatric admissions both in and outside the metropolitan area had comorbid chemical abuse disorders. Seventy-five percent of patients in the metropolitan area with comorbid chemical abuse had a drug abuse disorder; in rural areas 88 percent of patients with chemical abuse disorders abused alcohol. Both hospital- and community-based aftercare services, especially in the metropolitan area, were less available to psychiatric patients with chemical abuse than to patients without these disorders. 相似文献
994.
R Benigni M Cotta-Ramusino C Andreoli 《Journal of toxicology and environmental health》1991,34(3):397-407
This paper is a quantitative analysis of the relationship between the chemical structure and the Salmonella mutagenicity of a number of chlorofluorocarbons (CFC). The molecules were characterized by both molecular orbital and physical chemical parameters. The results of the analysis indicated that the CFC mutagenicity is correlated with two parameters: the free energy of binding to biological receptors, and the energy of the highest occupied molecular orbital (HOMO). Since these are the same factors that would favor the cytochrome P-450-catalyzed metabolism, it would appear that the CFC mutagenicity is determined more by the rate of initial activation than by the rate of DNA attack. 相似文献
995.
V L Towle J C Witt S H Nader A T Reder R Foust J P Spire 《Electroencephalography and clinical neurophysiology》1991,80(5):339-346
Pattern visual evoked potentials were obtained from 46 patients with definite relapsing/remitting multiple sclerosis, using both a conventional 5-channel occipital array and a 3-D recording technique consisting of three bipolar derivations approximating the three dimensions of space. These three orthogonal wave forms were displayed as a 3-D Lissajous trajectory for each subject. Two of the 15 patients with completely normal conventional pattern VEPs had abnormalities of the orientation of the B-C curvilinear segment of the 3-D pattern VEPs. Delays in the first major occipital positive component (P100) were evident using both techniques; the correlation between P100 latency and the latency of the corresponding trajectory apex was r = 0.99 (P less than 0.01). Post-chiasmal MRI abnormalities were associated with 3-D VEP orientation abnormalities. Three-dimensional pattern VEPs are moderately more sensitive than conventional pattern VEPs at detecting dysfunction posterior to the optic chiasm in demyelinating disease and do not require the use of eccentric fixation to do so. 相似文献
996.
Thyroid function tests were studied in 105 severely disabled children. Fifty-four cases (53%) showed following abnormalities. Serum TSH concentration was increased in 2 cases. Both serum T4 and T3 levels were decreased in 18 cases (17%). Only the serum T4 level was decreased in 25 cases (24%). Only the serum T3 level was decreased in 10 cases (9.5%). Two patients showed primary hypothyroidism. Two patients (monozygotic twins) were suspected to have subclinical hypothalamic-pituitary hypothyroidism caused by septo-optic-dysplasia. Abnormal thyroid functions were caused by anticonvulsants in most patients. The serum T4 level was correlated with the number of anticonvulsants, but not correlated with motor performance (daily activity) or feeding function. Four patients who had low T4 level or low T4 and T3 levels were received L-thyroxine supplementation, but no clinical improvement was observed. The serum TSH concentration was decreased and the TRH test showed hyporeaction in all of these cases. The low T3 level and normal T4 level were not related to anticonvulsant administration. Two of these patients were in poor nutritional condition, resulting in so called low T3 syndrome. 相似文献
997.
998.
Changes in women's mental and physical health from pregnancy through six months postpartum 总被引:1,自引:0,他引:1
A longitudinal study was conducted to investigate changes in women's mental and physical health around the time of childbirth, and to determine whether health was related to length of maternity leave. Thirty-seven married, employed first-time mothers completed questionnaires during pregnancy, and again at 6 weeks, 3 months, and 6 months postpartum. Results showed that, from pregnancy to the 6th postpartum month, the number of days that mothers were ill because of infections steadily increased. In addition, depressive symptoms for new mothers rose from pregnancy to the 6th week postpartum, and declined thereafter. For women who did not return to work during the period of the study, a significant decline in depressive symptoms was observed from the prenatal period through the 6th postpartum month. These findings demonstrate significant changes in mental and physical health for this group of first-time mothers. 相似文献
999.
Gonadotrophin-releasing hormone agonists (GnRHAs) were investigated as contraceptive agents from the late 1970's to the mid-1980's. They were abandoned as they appeared to offer no advantage over conventional combination-type oral contraceptives (COCs). This conclusion appears to be incorrect. We propose here a contraceptive regimen of a depot formulation of a GnRHA plus add-back estrogen and intermittent progestogen. The dose of add-back sex-steroids is substantially less than that in COCs; this reduction in sex-steroids should lead to a major reduction in lifetime breast cancer occurrence. 相似文献
1000.
Following an encephalopathic illness, a 13-year-old Chinese boy had a partial form of Klüver-Bucy syndrome with emotional disturbance, recent memory loss, hypersexuality, and polyphagia. Other unusual features included narcolepsy, polydipsia, and polyuria. Virologic studies failed to incriminate the etiologic agent, including herpes simplex virus. Brain biopsy of the frontal lobe demonstrated Alzheimer type II astrocytosis. 相似文献