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Effect of intraperitoneal injection of tetrapeptide A10 (H-Tyr-D-Orn-Phe-Gly-OH), selective -opiate receptor agonist, synthetic analog of dermorphine, in a dose of 100 g/kg on DNA synthesis and protein content in the myocardium was studied in albino rats. Five injections of tetrapeptide on days 2-6 after birth caused no changes in DNA synthesis 17 days after the last injection, i. e. in 24-day rats. The number of nucleoli and their area increased. In adult males long-term (3-week) treatment with tetrapeptide A10 increased the number of nucleoli and the mean and integral optical density of isolated cardiomyocytes stained with amido black B, which probably attested to activation of protein synthesis in the myocardium. Simultaneously, the content of catecholamines in the heart increased. These data are comparable with delayed effects of k-opiate receptor agonist dinorphine A1-13 and indicate that morphogenetic properties of opioid peptides in rat myocardium are realized via the same routes.  相似文献   
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Interstitial chromosomal deletions at 22q11.2 and 7q11.23 are detected in the vast majority of patients affected by CATCH 22 syndromes and the Williams-Beuren syndrome, respectively. In a group of 15 Williams- Beuren patients, we have shown previously that a large number of 7q11.23 deletions occur in association with an interchromosomal rearrangement, indicative of an unequal crossing-over event between the two homologous chromosomes 7. In this study, we show that a similar mechanism also underlies the formation of the 22q11.2 deletions associated with CATCH 22. In eight out of 10 families with a proband affected by CATCH 22, we were able to show that a meiotic recombination had occurred at the critical deleted region based on segregation analysis of grandparental haplotypes. The incidences of crossovers observed between the closest informative markers, proximal and distal to the deletion, were compared with the expected recombination frequencies between the markers. A significant number of recombination events occur at the breakpoint of deletions in CATCH 22 patients (P = 2.99x10(-7)). The segregation analysis of haplotypes in three- generation families was also performed on an extended number of Williams-Beuren cases (22 cases in all). The statistically significant occurrence of meiotic crossovers (P = 4.45x10(-9)) further supports the previous findings. Thus, unequal meiotic crossover events appear to play a relevant role in the formation of the two interstitial deletions. The recurrence risk for healthy parents in cases where such meiotic recombinations can be demonstrated is probably negligible. Such a finding is in agreement with the predominantly sporadic occurrence of the 22q11.2 and 7q11. 23 deletions. No parent-of-origin bias was observed in the two groups of patients with regard to the origin of the deletion and to the occurrence of inter- versus intrachromosomal rearrangements.   相似文献   
34.
Some new 4-methyl-1,2,3,4-tetrahydroquinolines containing propyl, phenyl and pyridyl radicals at the C-2 position were synthesized from readily available N-aryl-N-alkenylamines. The latter and the tetrahydroquinolines obtained were tested for bactericidal, fungicidal, and herbicidal activities. Among the tetrahydroquinolines tested, those containing an -, -, or -pyridyl substituent have found to be most potent as fungicides.  相似文献   
35.
There has been carried out an analysis of treatment of 134 patients with habitual shoulder-slips according to 4 known methods and I proposed by the authors. There has been detected a number of typical defects, made by doctors in the process of treatment during acute period. The essence of the proposed method consists in strengthening by lavsan bandage "North-CITO" of the anterior part of the shoulder joint that allows to begin early restorative treatment.  相似文献   
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Background: The purpose of the present paper was to describe the clinical manifestations and treatment of patients with panniculitis. Methods: From January 1983 to December 2002, 4294 patients were treated for pediatric rheumatological diseases at Pediatric Rheumatology Unit, University of São Paulo, Brazil. Of these, 35 children and adolescents (0.8%) presented with panniculitis: erythema nodosum (EN) or Weber–Christian disease (WCD). Clinical characteristics, laboratory exams, biopsy of the lesion, treatment and clinical course were studied. Results: Of the 35 patients, 29 presented with EN and six with WCD, one of these with cytophagic histiocytic panniculitis. Mean age at symptom onset was 85 months (6–204 months) and the mean duration of follow up was 55 months (1–144 months). All the patients presented with inflammatory subcutaneous nodules. The patients with WCD presented with systemic manifestations and cutaneous atrophy. The principal etiologies of EN were streptococcal infection (42%), undetermined (13.5%), pulmonary tuberculosis (10%), and acute rheumatic fever (10%). Biopsy of the nodules indicated septal panniculitis in 14 patients with EN and lobular panniculitis without vasculitis in the patients with WCD, one of which had cytophagic histiocytic panniculitis. There was recurrence in 11 patients (38%) with EN and in all those with WCD. Non‐steroidal anti‐inflammatory drugs were used in 15 patients with EN and corticosteroids and/or immunosuppressive drugs in the six patients with WCD. Three patients died. Conclusions: EN is the most frequent panniculitis, with a benign course and is mainly associated with infections. WCD is a severe disease, with systemic involvement, that proceeds with cutaneous atrophy and requires the use of corticosteroids and or immunosuppressive drugs.  相似文献   
39.
Selective vulnerability of spinal cord motor neurons to non-NMDA toxicity   总被引:6,自引:0,他引:6  
Saroff D  Delfs J  Kuznetsov D  Geula C 《Neuroreport》2000,11(5):1117-1121
We previously reported that alpha-motor neurons in organotypic cultures of rat spinal cord (OTC-SC) are resistant to excitotoxicity induced through NMDA receptors. Here we describe the effects of non-NMDA glutamate receptor agonists kainic acid (KA) and quisqualic acid (QUIS) on motor neurons in OTC-SC. Large ventral horn acetylcholinesterase-positive neurons (VHANs), most of which are motor neurons, were quite sensitive to QUIS and KA toxicity and displayed losses of 95% and 94%, respectively. Small VHANs were reduced by 41% and 61% only. Identical results were obtained in cultures stained for non-phosphorylated neurofilaments. These observations demonstrate that alpha-motor neurons are considerably more sensitive to KA and QUIS than to NMDA toxicity. The proposed excitotoxic mechanism of ALS, therefore, is most likely mediated through non-NMDA glutamate receptors.  相似文献   
40.
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses.  相似文献   
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