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We have used intracellular dye-filling combined with multiple-labelling immunofluorescence to examine the dendritic morphology of neurons and their relations with neuropeptide-containing preganglionic terminals in the lumbar sympathetic chain of guinea-pigs. Presumptive vasoconstrictor neurons with immunoreactivity for both tyrosine hydroxylase and neuropeptide Y dendritic fields that were significantly smaller, on average, than those of presumptive pilomotor neurons containing immunoreactivity to tyrosine hydroxylase but not to neuropeptide Y. However, there was considerable variation in the sizes of the dendritic fields of the vasoconstrictor neurons. Preganglionic nerve terminals containing immunoreactivity to calcitonin gene-related peptide, but not to substance P, only surrounded cell bodies of vasoconstrictor neurons containing immunoreactivity to tyrosine hydroxylase and neuropeptide Y. In most cases, the neuropeptide-containing preganglionic terminals were not associated closely with the distal dendrites of these neurons. Few neuropeptide-containing terminals were associated closely with either the cell bodies or dendrites of the pilomotor neurons. These results show that there is a considerable range in the size of dendritic trees of sympathetic final motor neurons. Some of this variation is related to the pathways within which the neurons lie, so that presumptive pilomotor neurons generally are larger than presumptive vasoconstrictor neurons. The marked variation in size of vasoconstrictor neurons raises the possibility that there may be a size dependent recruitment of these neurons, similar to that seen in pools of spinal motor neurons. The distribution of the peptide-containing preganglionic endings suggests that they would act predominantly at the cell body and proximal dendrites of the final motor neurons. 相似文献
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A structured interview and standardized rating scales were used to assess a sample of 194 outpatients with schizophrenia in a regional Australian mental health service for substance use, abuse, and dependence. Case manager assessments and urine drug screens were also used to determine substance use. Additional measurements included demographic information, history of criminal charges, symptom self-reports, personal hopefulness, and social support. The sample was predominantly male and showed relative instability in accommodations, and almost half had a history of criminal offenses, most frequently drug or alcohol related. The 6-month and lifetime prevalence of substance abuse or dependence was 26.8 and 59.8 percent, respectively, with alcohol, cannabis, and amphetamines being the most commonly abused substances. Current users of alcohol comprised 77.3 percent and current users of other nonprescribed substances (excluding tobacco and caffeine) comprised 29.9 percent of the sample. Rates of tobacco and caffeine consumption were high. There was a moderate degree of concordance between case manager determinations of a substance-use problem and research diagnoses. Subjects with current or lifetime diagnoses of substance abuse/dependence were predominantly young, single males with higher rates of criminal charges; however, there was no evidence of increased rates of suicide attempts, hospital admissions, or daily doses of antipsychotic drugs in these groups compared with subjects with no past or current diagnosis of substance abuse or dependence. Subjects with a current diagnosis of substance use were younger at first treatment and currently more symptomatic than those with no past or current substance use diagnosis. The picture emerging from this study replicates the high rate of substance abuse in persons with schizophrenia reported in North American studies but differs from the latter in finding a slightly different pattern of substances abused (i.e., absence of cocaine), reflecting relative differences in the availability of certain drugs. 相似文献
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AG González NL Alvarenga AG Ravelo IA Jiménez IL Bazzocchi NJ Canela LM Moujir 《Canadian Metallurgical Quarterly》1996,43(1):129-132
OBJECTIVE: To calculate and compare the costs of the treatment of varicocele by antegrade scrotal sclerotherapy with other modalities. PATIENTS AND METHODS: A total of 2305 operations using antegrade scrotal sclerotherapy to treat varicocele in childhood and adolescence were analysed for cost factors and compared with different surgical treatment methods for varicocele. RESULTS: Calculation of the pre-, intra- and post-operative costs showed that antegrade scrotal sclerotherapy was the most economically effective of all forms of surgical management for varicocele. CONCLUSIONS: Because antegrade scrotal sclerotherapy is a cost-effective treatment for varicocele, the indications for treatment may be widened to include more men with potential infertility, and thus avoid the need for expensive methods of artificial fertilization. 相似文献
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Problem areas within a proficiency testing (PT) program are performance evaluation and sample stability. The different units used in the various T3 uptake methodologies make performance evaluation complex. To facilitate this evaluation, a normalization method for T3 uptake performance evaluation has been developed. Sample stability studies for T3 uptake indicate that, at room temperature, sample values increase after storage for about seven days. Room temperature sample stability studies for T4 using a competitive protein binding (CPB) method indicate that the apparent T4 content of pooled serum increases after about one week. Fatty acids are shown to be an interfering substance in the T4 CPB method as well as the T4 radioimmunoassay (RIA) method. This interference increases with a decrease in carbon chain length from C18 to C12 and with an increase in unsaturation of fatty acids. The B/B0 ration for arachidonic acid at a concentration of 0.48 micronMoles per tube is 17.4 in a CPB method and 87.1 in a radioimmunoassay method indicating that the greater effect is in the CPB method. The increase in T3 uptake values are probably also due to the interfering effect of fatty acids. 相似文献
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Hip involvement in ankylosing spondylitis (AS) is a common and disabling problem. The clinical and x-ray records of 87 patients with definite AS (Rome criteria) were examined to define and characterize their hip disease. Clinical hip disease was present in 33 cases (38%), was usually bilateral (91%), and tended to begin early in the disease course; it was the cause of 50% of the Class III and IV disability in the entire study group. Typical findings included regional pain, limitation of motion, muscle atrophy, and flexion contractures. Radiologic hip abnormalities occurred in 42 cases (48%). The radiographic pattern was distinctive when compared to that in two control groups and included axial migration of the femoral head (63%), concentric joint space narrowing (50%), rufflike femoral osteophytosis (36%), and protrusio acetabuli (30%). Eight patients required bilateral hip surgery. Para-articular ossification occurred in 8 of 16 replaced hips; in 5 of 8 hips it caused clinical immobility. This potentially serious complication may limit the usefulness of hip arthroplasty in some AS patients. 相似文献
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