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101.
OBJECTIVE: A pattern of chronic adult antisocial behavior is not sufficient for the DSM-III-R diagnosis of antisocial personality disorder unless the early-onset criteria are satisfied, even if the adult criteria are met. The utility of the early-onset requirement for the diagnosis was examined in intravenous drug abusers, a population known to have high rates of irresponsible, aggressive, and criminal behavior. METHOD: The subjects were 237 drug abusers who had volunteered for an outpatient study of psychopathology and HIV risk behavior and infection. They completed a structured psychiatric interview as part of their participation in that study. The adult antisocial behavior of the group that met both the early-onset and the adult criteria for antisocial personality disorder, the group that met only the adult criteria, and the group that met neither the early-onset nor the adult criteria was then compared. RESULTS: Antisocial personality disorder (meeting the early-onset and adult criteria) was diagnosed in 44% of the sample; an additional 24% met only the adult criteria. The group with the diagnosis of antisocial personality disorder reported a more pervasive and more serious pattern of adult antisocial behavior than did the other groups, although antisocial behavior was commonplace in all three groups. CONCLUSIONS: Early onset of multiple antisocial behaviors identified a subset of drug abusers with important differences in the extent and severity of their adult antisocial behavior. The antisocial behavior of the group that met only the adult criteria suggests the possibility of a late-onset and less severe form of antisocial personality disorder.  相似文献   
102.
Twelve measures commonly used to assess attentional processes were examined in a sample of 120 outpatients referred for neuropsychological evaluation. A single factor solution emerged. A second analysis partially replicated factors derived by Shum. McFarland, Bain, and Humphreys (1990). Classification rates (impaired vs. unimpaired) for the measures are presented. The implications of these findings for clinical assessment of attention are discussed  相似文献   
103.
For the optimal timing of application of radiosensitizers in a course of radiotherapy it is important to know the sensitizer concentration at the time of irradiation. We have studied the pharmacokinetics of the hypoxic cell sensitizer isometronidazole in man and mouse and analyzed the data on the basis of an open two-compartment model after extravasal application. The parameter estimation is performed directly to avoid estimation biasing and data points from blood and tissue compartments are approximated simultaneously. The values obtained differ significantly from the estimations calculated by other authors for the same data.  相似文献   
104.
The behavioural and biochemical effects of the non-competitive N-methyl-D-aspartate (NMDA) receptor antagonists, dizocilpine and memantine, and the competitive NMDA receptor antagonist, CGP 39551, were investigated in rats. Systemic injections of dizocilpine (0.33 mg/kg) increased locomotion and rearing in an open field, whereas memantine (20 mg/kg) increased only locomotor activity. CGP 39551 (10 and 20 mg/kg) did not change open field activity. Dopamine (DA) metabolism--as measured by the ratio of dihydroxyphenylacetic acid/dopamine (DOPAC/DA)--increased in response to dizocilpine in the prefrontal cortex and the nucleus accumbens. Memantine enhanced DOPAC/DA in the prefrontal cortex, the nucleus accumbens and to a lesser degree in the posterior striatum. In contrast to non-competitive NMDA receptor antagonists, CGP 39551 did not increase DA metabolism of subcortical structures and even decreased DOPAC/DA in the prefrontal cortex. These results indicate that competitive and non-competitive NMDA receptor antagonists affect spontaneous locomotion differentially in rats. The biochemical data imply that the stimulant actions non-competitive NMDA receptor antagonists are at least partially due to activation of ascending dopaminergic systems. Potential mechanisms involved in the differential effects of both types of NMDA receptor antagonists are discussed.  相似文献   
105.
The correlation between the occurrence of Graves' ophthalmopathy and Graves' hyperthyroidism may indicate a role for tri-iodothyronine (T3) hormone in the pathogenesis of Graves' ophthalmopathy. In Graves' ophthalmopathy the recti eye muscles are greatly enlarged whereas skeletal muscles seem unaffected. The distribution of the nuclear T3 receptor was studied in normal human and rat eye and skeletal muscles with immunohistochemistry using mouse (monoclonal) antibodies, and by in-situ hybridization for the detection of mRNA encoding the T3-receptor protein. Nuclear staining with T3-receptor antibodies was found in all types of tissues studied. Cytoplasmic staining occurred predominantly in the muscle fibres of the orbital layer of the eye muscles and was generally absent or very low in skeletal muscle fibres and hepatocytes. Immunostaining could be inhibited by preabsorbing the antibodies with bacterially expressed T3-receptor protein, implying specificity. The presence of nuclear and cytoplasmic hormone-free T3 receptor sites was indicated after preincubation of sections with T3 hormone; T3-receptor immunostaining decreased and T3-hormone staining increased. In-situ hybridization clearly revealed the presence of alpha-1 and beta-1 forms of the T3-receptor mRNA in liver, skeletal muscles, and orbital and intermediate layers of the eye muscles. The data demonstrate the presence of T3 hormone-receptor molecules in the extraocular and skeletal muscles. The different susceptibilities of these muscles to Graves' hyperthyroidism may relate to the quantitative differences in T3 hormone-receptor distribution.  相似文献   
106.
The treatment planning for radiotherapy with fast neutrons requires modifications of the planning systems used for photons. The neutron- and photon-component of the treatment fields must be determined and can then be used for separate calculations. The corrections for inhomogeneities are performed by use of attenuation coefficients and the corresponding corrections for changes in the kerma. The treatment planning system MEVAPLAN (Siemens) was modified to follow these requirements. Thus treatment planning for 14 MeV DT-neutrons could be performed. The multiplanar option is used to calculate 3D-dose distributions based on up to 40 serial CT slices. The generated three-dimensional dose matrix and the CT data are transferred via magnetic tape to the visualization system VOXEL-MAN developed at the University Hospital of Hamburg. This system uses a ray casting algorithm based on the generalized Voxel-model to display detailed 3D-images of human anatomy together with the calculated dose distribution. Different treatment plans for neutrons and photons are calculated and visualized. Various manipulations of the data-sets are displayed to improve the critical examination of the simulated dose distribution and to discern the quality of treatment techniques.  相似文献   
107.
108.
Summary We studied the effects of repeated intra-articular injections of sterile 140 mM NaCl solution on articular cartilage in adult rabbits. After 20 injections into the knee joints over a period of 4 weeks, chondrocyte glucosaminoglycan synthesis was evenly reduced in all cartilage layers, accompanied by a significant proteoglycan depletion of the matrix which was most marked in the superficial half of the cartilage. These and other changes only partially reversed during a further 4-week period after the injections had been stopped. Our data underline the need for a clear-cut indication for intra-articular injections. The microtrauma caused by injection, in conjunction with the introduction of a carrier solution into the joint, may, at least when repeated at short intervals, lead to measurable damage to the articular cartilage.Recipient of grant no. Ne 308/1-1 from the Deutsche Forschungsgemeinschaft, Bonn, Germany  相似文献   
109.
110.
We determined an operational value for the lumped constant to be used in measurements of the local rate of cerebral glucose use (lCMR(glc)) with FDG in normal adult male rats. METHODS: The standard quantitative autoradiographic method was used with 2-deoxy-d-(14)C-glucose ((14)C-DG) and with (14)C-FDG in awake normal adult male rats. Timed arterial blood samples were drawn for 45 min after the bolus and assayed for plasma glucose and (14)C concentrations. At the end of the 45-min experimental period, the rats were killed, and their brains were removed and divided in half sagittally. One hemisphere was immediately frozen and assayed for local (14)C concentrations by quantitative autoradiography; the other was weighed, homogenized in t-octylphenoxypolyethoxyethanol solution, and assayed for (14)C concentrations in the whole brain by liquid scintillation counting. Paired rats (3 pairs), one in each pair receiving (14)C-DG and the other receiving (14)C-FDG, were studied in parallel on the same day. Additional unpaired animals (n = 8) were studied with either (14)C-DG or (14)C-FDG but not in parallel on the same day. To calculate the lCMR(glc) in rats studied with (14)C-FDG, the rate constants for (14)C-FDG were estimated from the (14)C-DG values determined for rats and the (14)C-FDG/(14)C-DG ratios determined for humans. In all of the rats studied with either (14)C-DG or (14)C-FDG, the lCMR(glc) was first calculated in 12 representative brain structures with the lumped constant of 0.48 previously determined for (14)C-DG in rats. The ratio of the lCMR(glc) thus determined with (14)C-FDG to that determined with (14)C-DG for each structure was then multiplied by the lumped constant for (14)C-DG to estimate the lumped constant for (14)C-FDG. The lCMR(glc) and the lumped constant for FDG in the brain as a whole were similarly estimated from the tracer concentrations in the brain homogenates. RESULTS: The mean values for the lumped constant for FDG were found to be 0.71 and 0.70 in the autoradiographic assays and the assays with brain homogenates, respectively. CONCLUSION: The appropriate value for the lumped constant to be used in determinations of the lCMR(glc) in normal adult male rat studies with (18)F-FDG and small-animal PET scanners is 0.71.  相似文献   
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