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571.
S Sartini R Cuppini P Ambrogini T Cecchini C Bruno P Del Grande E Bombardelli 《Bollettino della Società italiana di biologia sperimentale》1991,67(7):691-697
During motor nerve regeneration a transitory polyinnervation of muscle cells occurs, which represents a phase of rearrangement of the recovered innervation. Bilobalide, a terpene extrated from Ginkgo biloba leaves, was proposed to affect some aspects of nervous system development and regeneration. In this work, influence of bilobalide on polyinnervation in reinnervated extensor digitorum longus muscle was studied, through electrophysiological and histological techniques. The muscle was denervated crushing the sciatic nerve and it was examined at 1 or 2 months after denervation. The polyinnervated muscle cells in controls reached 24% at 1 month and thus the percentage decreased. In muscles of bilobalide treated rats the number of polyinnervated cells was decreased at both times. 相似文献
572.
Ademir R. Ruschel Rubens O. Nodari Bruno M. Moerschbacher 《Biodiversity and Conservation》2007,16(6):1699-1714
This paper presents a quantitative inventory of woody plants with DBH ≥ 5 cm in Turvo State park, a large remnant (17,500 ha)
of seasonal deciduous Atlantic forest in Southern Brazil. The forest inventory was based on 141 sampling points (point centered
quarter method). Seventy-eight species from 37 families were recorded, the density was 879 plants ha−1 and the basal area 25.12 m2 ha−1. Timber species of commercial value made up 35% of the species and 72% of the basal area. The ten most abundant species made
up 52% of the species, and the ten species with highest basal area accounted for 48% of the total basal area and 12% of the
species. Zoochory was the dominant mode of seed dispersal, representing 63% of species and 67% of the plant density. Nine
percent of the species were pioneers, 56% were secondary species accounting for 62% of the total basal area, and 35% were
opportunistic-climax species accounting for 54% of the plant density. Turvo park has exceptionally high biodiversity and is
the last intact large remnant of the Alto-Uruguai river ecosystem. In addition to species richness and an abundance of high
value timber species, this forest is of value for the rich genetic resources, and for medicinal and ornamental plants. 相似文献
573.
Two new species of Rutaceae, Conchocarpus hamadryadicus Pirani & Kallunki and C. minutiflorus Groppo & Pirani are described and illustrated. Both are known so far only from small remnants of forests, the former in the
caatinga dominium in Bahia, the latter in moist forests near Santa Teresa, Espírito Santo, Brazil. Their main diagnostic features
are delineated, and their relationships to other species of Conchocarpus are discussed. Because Rauia racemosa Nees & Mart. can no longer be recognised as a synonym of Conchocarpus fontanesianus (A. St.-Hil.) Kallunki & Pirani, a new combination, C. racemosus (Nees & Mart.) Kallunki & Pirani, is provided, with comments. 相似文献
574.
S C Chattoraj D J Cecchini T F Brennan K C Edelin A V Chobanian H H Wotiz 《Steroids》1983,42(6):603-607
Since catechol estrogens are potent competitive inhibitors of catechol-O-methyl transferase (COMT), it has been suggested that they may prolong the half-life of catecholamines which in turn can cause hypertension. Thus, experiments were carried out to study the effect of catechol estrogens on blood pressure in the male rat following chronic administration. Results demonstrate that 2-hydroxyesterone (2,3-dihydroxyestra-1,3,5(10)-trien-17-one) and 2-hydroxy-estradiol (estra-1,3,5(10)-triene-2,3,17 beta-triol) even when administered in high doses do not alter blood pressure. 相似文献
575.
S Ciaroni T Cecchini F Battelli P Del Grande 《Zeitschrift für mikroskopisch-anatomische Forschung》1990,104(6):898-906
The reduction of the forceps major of the corpus callosum was estimated quantitatively in relation to the lesions to the neocortex in animals to which methylazoxymethanol-acetate (MAM) had been administered on the 13 th, 15 th or 17 th day of embryonic development. The specimens which received a prenatal injection of MAM the 13 th or 15 the day of gestation show noticeable reductions in both the extension of the occipital neocortex and the forceps major of the corpus callosum. Parallelly in MAM 13 there is a significant reduction in cell density both in the deeper layers and the more superficial ones, whereas in MAM 15 only the supragranular layers seem to be altered. Such a quantitative analysis shows a close correlation among the decreases in the area of the forceps major of the corpus callosum, in the area of the occipital neocortex and in cell density of the infragranular and supragranular layers. 相似文献
576.
577.
García Pedro García Ernesto Ronda Concepción Tomasz Alexander López Rubens 《Current microbiology》1983,8(3):137-140
Current Microbiology - We have prepared an antiserum against a new lytic enzyme (PAL) that has recently been isolated and purified from a mutant ofStreptococcus pneumoniae infected with the... 相似文献
578.
Lipid peroxidation rate in four different hepatomas is quite different and seems to be related to their degree of deviation, low deviation tumours displaying higher peroxidative ability. Moreover, the supernatant of the highly anaplastic Yoshida hepatoma is able to decrease the peroxidation rate in normal liver microsomes. This antioxidant ability is not dependent upon an increased level of glutathione. The concentration of reduced glutathione (GSH) declines strongly during incubation in conditions favouring lipid peroxidation. Unlike normal liver homogenates, this decline of GSH in hepatomas is not due to the transformation of GSH into oxidized glutathione (GSSG) but mostly to the increased activity of the γ-glutamyl-transpeptidase pathway. 相似文献
579.
S Ciatto S Cecchini G Grazzini A Iossa D Bartoli M P Cariaggi P Bulgaresi 《Acta cytologica》1989,33(6):894-898
The predictive value of fine needle aspiration (FNA) was assessed in 1,181 consecutive cases of breast lesions in which cytologic abnormalities were reported. The positive predictive value (PPV) of an FNA cytologic report of atypia, suspicious or positive was 0.49, 0.95 or 0.996, respectively. In the presence of a suspicious/positive report by both physical examination and mammography, the PPV of a cytologic report of suspicious was 0.99. The PPV was directly correlated with age, partly due to the incidence of fibroadenomas among younger patients; fibroadenomas were present in 53 of 146 cases with a false FNA report of atypia, in 10 of 19 cases with a false FNA report of suspicious and in 2 of 2 cases with a false FNA report of positive. Overall, 93 cases reported as benign by physical examination and mammography were biopsied on the basis of the FNA cytologic report; cancers were diagnosed in 33 of these 93 cases (6 cancers among 42 women less than 40 years old and 27 cancers among 51 women greater than 39 years old). The widespread use of FNA cytology to study breast lesions is thus recommended, without regard to patient age and even in the presence of clinically benign findings, since the increase in the rate of cancer detection is worth the excess of unnecessary biopsies. The predictive value of a positive report of FNA cytology, or even of a suspicious report in the presence of clinical suspicion, is so high that an intraoperative frozen section biopsy might be spared in such cases. 相似文献
580.
Urethral cytology of Cytobrush specimens. A new technique for detecting subclinical human papillomavirus infection in men 总被引:2,自引:0,他引:2
S Cecchini I Cipparrone M Confortini A Scuderi L Meini G Piazzesi 《Acta cytologica》1988,32(3):314-317
Cytologic examination of urethral smears prepared with the Cytobrush and colposcopic examination of the penis were performed in 53 male partners of women with cervical human papillomavirus (HPV) infections and in 14 healthy controls. A diagnosis of HPV infection was recorded in 28 subjects (52.8%). Cytology was positive in 26 cases (49%) and colposcopy was positive in 5 cases, with both tests positive in 3 cases. No controls were positive by cytology or colposcopy. These findings suggest that urethral cytology and colposcopic examination should be routinely performed in partners of women with HPV infections to detect inapparent infections. The Cytobrush should be employed for the urethral cytologic sampling; smears prepared by other techniques (urine collection or urethral swabbing) yield lower detection rates. 相似文献