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991.
When reaction of N,N-dialkyl-alpha-ethoxycarbonyl-alpha-alkylacetamides with beta-naphthol in the presence of phosphorus oxychloride was carried out in chlorobenzene at reflux, formation of 1-oxo-2-alkyl-3-dialkyl-amino-1H-naphtho[2,1-b]pyrans was achieved together with some other products whose structure was defined. Moreover, substitution of the 2 position of 1-oxo-3-dialkylamino-1H"naphtho[2,1-b]pyrans with chlorine or cyano group as well as the preparation of 1-thio-3-dialkylamino-1H-naphtho[2,1-b]pyrans was obtained by suitable chemical methods. Pharmacological screening of these compounds showed the lack of psychotropic activity of the corresponding 1-oxo-3-dialkylamino-1H-naphtho[2,1-b]pyrans. 相似文献
992.
A large number of studies have been carried out to identify the Friend leukemia virus (FV) target cell(s). In FV-infected mice, the kinetics of "primitive" erythroid burst-forming units (P-BFU-E) is perturbed, and their proliferative rate is enhanced. These results indirectly suggest, but do not prove, that cycling P-BFU-E may serve as FV target. In vitro infection studies showed that normal erythroid colony forming units (CFU-E) and "mature" erythroid burst-forming units (M-BFU-E) are targets for FV, while the largely out-of-cycle normal P-BFU-E are not. In an attempt to shed light on these aspects, we have evaluated the expression of viral cytoplasmic RNA sequences in pools of colonies generated by P-BFU-E and granulocyte-macrophage colony forming units (CFU-GM) from spleen and marrow of polycythemic Friend virus (FVP)-infected mice, as measured by liquid hybridization with FVP- or spleen focus-forming polycythemic virus (SFFVp)-specific DNA probes. Moreover, similar assays were performed on RNAs derived from whole spleen or bone marrow from mice treated with FVP or the anemic strain of Friend virus (FVA). Control studies were performed on corresponding colonies and whole tissues from normal animals. FVP- and SFFVp-specific sequences are more abundant in RNA extracted from infected spleen as compared to marrow by a 10-fold factor. On the other hand, FVP and SFFVp-specific sequences are expressed at a comparable level in both P-BFU-E- and CFU-GM-derived colonies from spleen or marrow of FVP-treated mice. Since in vitro spread of FVP infection was excluded by control studies with addition in culture of antibody to the viral glycoprotein with a molecular weight of 70,000 (gp70) these results indicate that P-BFU-E and CFU-GM are infected in vivo by FVP. 相似文献
993.
M F Di Renzo L Doneda L Larizza P M Comoglio 《International journal of cancer. Journal international du cancer》1983,31(4):455-461
Previous work has shown that the metastatic potential of RSV-transformed fibroblasts is correlated with the ability to form colonies in 0.6% ("hard") agar. Metastatic subclones were selected by this property from the non-metastasizing fibrosarcoma B77-313 line. A marker chromosome was found at high frequency (90% of cells) in all the subclones studied. This marker was detectable in only 0.5% of the parental B77-3T3 cells, demonstrating that metastatic clone precursors pre-existed, as a small minority, in the parental line. The genotypic marker appeared to be steadily associated with the metastatic phenotype since, after prolonged in vitro propagation, the subclones retained both the marker chromosome and the high metastatic potential. Although the marker chromosome was constantly present, chromosomal numerical and structural aberrations were also found in 20% of the long-term-propagated subclone cells, supporting the suggestion that metastatic properties are associated with cytogenetic instability. 相似文献
994.
Abstract
Session 12 Acceptance and effectiveness of modern contraception: A comparison of Western and Central Europe 相似文献995.
Biffo S Pognetto MS Di Cantogno LV Perroteau I Fasolo A 《The European journal of neuroscience》1992,4(12):1398-1406
Primary olfactory neurons located in the olfactory neuroepithelium project to the ipsilateral olfactory bulb and undergo a continuous process of neurogenesis and differentiation. We describe, in the adult rat, the kinetics of proliferation, differentiation and survival of primary olfactory neurons either in the presence or absence of their target, the olfactory bulb. The experimental design included unilateral bulbectomy, coupled with a single bromodeoxyuridine pulse 35 days after surgery. The rate of proliferation and survival of olfactory neurons was then examined by immunohistochemistry for bromodeoxyuridine, and the differentiation status by in situ hybridization for calmodulin messenger RNA in immature and mature olfactory neurons and immunohistochemistry for the dipeptide carnosine in mature olfactory neurons. We show that primary olfactory neurons can synthesize carnosine in the absence of the olfactory bulb. However, the number of carnosine-immunopositive neurons in the absence of their target is dramatically reduced to less than one-fourth, whereas the number of olfactory neurons expressing calmodulin messenger RNA is only slightly reduced. The numeric reduction of camosine-positive neurons in the target-deprived neuroepithelium is correlated with a dramatic reduction in the survival rate of olfactory neurons, since newly generated olfactory neurons are completely lost 35 days after the bromodeoxyuridine pulse. In contrast, in the normal olfactory neuroepithelium almost one-third of newly generated olfactory neurons survive 35 days after the bromodeoxyuridine pulse. On the whole, these data indicate that most of the primary olfactory neurons have a short lifespan but that once they have connected with the olfactory bulb they may persist longer, and suggest that throughout adulthood olfactory neurons are overproduced, differentiate independently from their target, and then undergo a process of target-induced neuronal selection. 相似文献
996.
P. Cugini P. Lucia L. Di Palma M. Re R. Canova L. Gasbarrone A. Cianetti 《Clinical autonomic research》1992,2(2):113-118
Atrial natriuretic peptide, vasoactive intestinal peptide, beta-endorphin and cortisol are humoral variables characterized by a 24-h periodicity. We evaluated the circadian rhythm of these peptides and hormones in healthy subjects who were young (between 20–25 years) or elderly (between 65–75 years). All were on controlled diets. Blood samples were collected six times during a 24-h period (at 06.00, 08.00, 12.00, 18.00, 20.00 and 24.00 h) beginning 8-h after start of recumbency. The time-related data were analysed by the Cosinor method in order to validate the circadian rhythm and to quantify rhythmometric parameters which included the midline estimate of rhythm (mesor). In contrast to the young subjects, Cosinor analysis failed to reveal a significant circadian rhythm in elderly subjects, for plasma cortisol. In elderly subjects oscillation (mesor) of atrial nutriuretic peptide was higher, while that of vasoactive intestinal peptide and beta—endorphins was lower. The results suggest changes in the physiological secretion of these three peptides in healthy elderly subjects. 相似文献
997.
Orlandi B. Baldassarre M. Camponozzi F. A. Stanislao C. Di Poccia G. Donatis D. De 《The Italian Journal of Neurological Sciences》1992,13(2):161-164
We report the case of a 22 year old woman with congenital generalized lipodystrophy who presented a left brachiocrural pyramidal hemisyndrome, bilateral cerebellar signs and a left cranial nerve VI deficit. The clinical pattern had a tendency to regress. MRI brainscan, CSF examination and clinical features led to the diagnosis of probable demyelinating syndrome. Published data on CNS involvement in patients with congenital generalized lipodystrophy are few and we have found no cases in which a demyelinating syndrome is associated. In the case we report it is tempting to see the disorder of the lipid metabolism underlying the congenital generalized lipodystrophy as underlying the myelin disorder as well.
Sommario Descriviamo il caso di una paziente di 22 anni, affetta da Lipodistrofia Congenita Generalizzata, che ha presentato una sintomatologia caratterizzata da emisindrome piramidale brachiocrurale sinistra, segni cerebellari bilaterali e deficit del VI nervo cranico di sinistra. Il quadro clinico ha avuto una tendenza alla regressione. La RMN encefalo, l'esame del liquor e la clinica hanno fatto porre diagnosi di probabile sindrome demielinizzante. I dati della letteratura relativi al coinvolgimento del SNC in pazienti con Lipodistrofia Congenita Generalizzata sono scarsi ed in particolare non abbiamo rilevato casi di associazione con sindrome demielinizzante. Nel caso descritto è suggestivo che la turba del metabolismo lipidico alla base della Lipodistrofia Congenita Generalizzata possa essere in rapporto all'interessamento della mielina.相似文献
998.
Craniocervical junction malformation treated by transoral approach. A survey of 25 cases with emphasis on postoperative instability and outcome 总被引:2,自引:0,他引:2
N. Di Lorenzo M.D. 《Acta neurochirurgica》1992,118(3-4):112-116
Summary An experience with 25 consecutive cases of craniocervical junction (CCJ) malformations operated upon via the transoral route is reported. Twenty-two patients also underwent posterior occipitocervical stabilization with alloplastic material and in only one patient was transoral odontoidectomy and fusion with bone autograph performed.Indication for the transoral route consisted of an irreducible ventral compression of the cervicobulbar junction by the abnormal bone complex.Two patients died during the early postoperative period and the remaining 23 survivors were followed for an average of 3.5 years: 17 of these showed marked improvement and 5 a stabilization of the neurological disturbances. A further patient, who refused posterior stabilization, eventually died because of progressive cranial settling.Long-term results have shown this approach to be decisive in the surgical management of well-selected CCJ anomalies. 相似文献
999.
Di Stefano M Lepore F Ptito M Bédard S Marzi CA Guillemot JP 《The European journal of neuroscience》1991,3(10):1016-1024
Visually responsive neurons have been recorded in the lateral suprasylvian area (LSA) of cats raised with either a convergent or a divergent strabismus. In contrast to areas 17 and 18, where many studies have documented a profound loss of binocularly activated neurons following early strabismus, in the LSA the majority of cells could still be binocularly driven. Acute or chronic section of the splenium of the corpus callosum reduced but did not abolish binocularity in the LSA. We propose that the widespread callosal connections, the large size of the receptive fields and the peculiar internal circuitry of the LSA all concur in permitting the maintenance of binocular coding in spite of early misalignment of the eyes. 相似文献
1000.
J R Fiore G Angarano C Fico L Monno G B Zimatore M Di Stefano C Fracasso G Pastore 《Acta neurologica》1991,13(1):31-36
Seven paired HIV-1 isolates from peripheral blood mononuclear cells (PMCs) and cerebrospinal fluid (CSF) of infected subjects at various stages of the disease were studied for their capacity to replicate in continuous cell lines (Molt-3 and U-937 cells) and to induce cytopathic effects "in vitro". Obtained results indicate that paired HIV-1 isolates from PMCs and CSF of the same patient can differ in their replicative activity "in vitro", suggesting that, at least in some cases, CSF isolates may represent a distinct subtype of HIV-1. 相似文献