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排序方式: 共有1819条查询结果,搜索用时 15 毫秒
1.
Anna Di Landro Lorenzo Marchesi Luigi Naldi Teresio Motta Tullio Cainelli 《Pediatric dermatology》1997,14(6):449-452
Abstract: Hypopigmented mycosis fungoides is a variant of mycosis fungoides characterized by the presence of hypopigmented patches as the sole manifestation of the disease. It has been described aimost always in young black or dark-skinned patients. The only white patient described was a 64-year-oid woman who not oniy had hypopigmented lesions, but also nodular lesions with lymphadenopathy. We describe hypopigmented lesions arising in a white boy 12 years of age, born in northern Italy, without any foreign ancestors. The microscopic alterations, with epidermotropism, the immunoiogic markers, the negativity of T-cell receptor gene rearrangement, and the good response to PUVA therapy correspond to the main findings in black patients with this disease. Long-term follow-up of these patients is important to obtain better knowledge of the natural history of the disorder, Hypopigmented mycosis fungoides must now be included in the differential diagnosis of hypopigmented macular lesions not only in black or dark-skinned patients but also in white patients. 相似文献
2.
A Miadonna A Tedeschi E Leggieri G Motta C Fabbri M Froldi M Agosti M Lorini A Marini C Zanussi 《International archives of allergy and applied immunology》1986,81(3):276-283
Basophil releasability was studied in 24 cord blood samples from normal-term deliveries. The histamine content in cord blood basophils was similar to that of adult blood basophils. The response to IgE-independent degranulating stimuli such as calcium ionophore A23187 and zymosan-activated human serum was overlapping with that of normal adults. Conversely, a reduced releasability was observed after challenge with anti-IgE, even after sensitization with an IgE-rich serum. The IgE-dependent degranulation seems to be hampered by the low concentrations of circulating and cell-bound IgE antibodies. The number of IgE molecules bound to the specific receptors in cord blood basophils is significantly lower than in adult blood basophils. 相似文献
3.
Changes occurring in the fine structure of Zona pellucida and follicular fluid in growing and atretic follicles in mice were examined by electron microscopy using lanthanum nitrate and ruthenium red. The results showed that follicular fluid has a dense globular aspect in growing follicles but becomes more dispersed and globular-fibrillar in atretic follicles. It is formed by rounded negatively charged particles (20 nm in diameter) that are closely packed in growing follicles, but spaced and united by filaments in atretic follicles. These changes may be related to a changed role of granulosa cells and also to an altered passage of nutritive substances from the plasma into the follicle. The Zona pellucida is intensely colorable only in the atretic follicles, where it is composed of a dense globular fibrous matrix, but not in growing follicles, where it reveals a weak reaction with ruthenium red. While in the Zona pellucida of growing follicles the globular negatively charged particles (20 nm in diameter) probably due to sialic acid moieties are rarely evident, these particles become highly numerous and connected by microfilamentous structures in atretic follicles. The altered electrical charge of polyanions may reflect a different chemical permeability of the Zona pellucida. Then the increase of negative charged particles in the zona may have a role in a process of sequestration of the oocyte during atreasia. 相似文献
4.
Intertubular capillary changes in kidney allografts: a morphologic investigation on 61 renal specimens. 总被引:8,自引:0,他引:8
A total of 61 kidney allograft specimens (51 biopsies and 10 nephrectomies) from 44 patients were investigated. Transplant glomerulopathy (TGP) was found in 38 specimens. Electron microscopy disclosed peculiar intertubular capillary changes (ITCC) in 47 specimens (all those showing TGP and nine without TGP). They were characterized by splitting and multilayering of the basement membranes. TGP and ITCC were graded and found mild (in 23 and 22 specimens), moderate (in 11 and 16 specimens), and severe (in four and nine specimens). Both worsened with time lapse from transplantation. When both were compared in single specimens, their grading was similar or, with a few exceptions, more severe for ITCC. TGP and ITCC were more frequent in biopsies with morphologic evidence of rejection and less frequent in patients treated with Cyclosporine A. Repeated biopsies and nephrectomies were studied in 10 patients and a somewhat more precocious appearance of ITCC than of TGP was found. Earlier and more severe ITCC were found in two patients who had had two transplants as compared to those with one. Morphologic similarities between TGP and ITCC suggest a common pathogenetic mechanism related to endothelial damage. The association to the histological evidence of rejection as well as the apparently protective activity of Cyclosporine A could support the involvement of an immune-mediated mechanism in agreement with what is reported in literature. The constant association of ITCC and TGP and its possible more precocious appearance enforce the diagnostic value of the former, which allows to infer the presence or the subsequent development of TGP even in biopsies where glomeruli are lacking. 相似文献
5.
Roentgen Stereophotogrammetric Analysis (RSA) has been applied to different kinds of research in order to obtain important information in the biomechanics field. Operative requirements change according to the type of investigation and sometimes practical conditions do not always permit one to respect standard specifications. The aim of this paper is to verify the reliability of the system under non-standard conditions, studying the effects of the focus-to-film distance on the determination of 3D co-ordinates of markers. The application of statistical analysis, consisting of two and three way ANalysis Of VAriance (ANOVA), showed that focus-to-film distance is not a significant source of variation, i.e., the system can correctly compute the marker position inside the calibrated space under all conditions of magnification. Since we obtained a fluctuation due to focal distance change of 10(-5) mm (LSD for 95% confidence level), we can assert that this source causes a variation strictly within the limits required by clinical investigations. Thus, this study contributes to improving the flexibility of RSA in clinical applications, making the technical requirements of the radiographic set-up less constraining. 相似文献
6.
Martin Benoît Marchaland Catherine Phillips John Chapouthier Georges Spach Colette Motta Roland 《Behavior genetics》1992,22(6):685-701
Recombinant congenic strains (RCS) represent a series of related strains, each of which carries a small fraction of the genome of one strain (donor strain) on the genetic background of another strain (background strain). Recombinant inbred strains (RIS) are commonly used to identify major gene segregation and linkage and associations between behavior and quantitative trait loci, whereas recombinant congenic strains (RCS) open other complementary leads. The variability in the reactivity of RCS to a trait is thus the expression of few minor-effect genes originating from the donor strain, because the probability that major genes are present in any one RCS is low. Unlike RIS in which minor-effect genes are often masked by major genes, RCS enable the effects of minor genes to be studied. With our method, for a given trait, an estimate can be made of the gene strength distribution as well as an estimate of the minimal number of genes involved having a certain strength.This study was supported by the Centre National de la Recherche Scientifique (URA 1924 and CSEAL-UPS 44, CNRS), Université René-Descartes, Paris V UFR Biomédicale, and the Fondation pour la Recherche Médicale. 相似文献
7.
Succinyl derivatives of N-tris (hydroxymethyl) methyl-2-aminoethane sulphonic acid: their effects on the frog neuromuscular junction. 下载免费PDF全文
J. del Castillo G. Escalona de Motta V. A. Eterovi P. A. Ferchmin 《British journal of pharmacology》1985,84(2):275-288
Succinic anhydride (SA) dissolved in Ringer solution buffered with N-tris (hydroxymethyl) methyl-2-aminoethane sulphonic acid (SA-TES solution) potentiates the depolarizing action of acetylcholine (ACh, 10-40 microM) on frog muscle and the tension induced by bath application of this agonist. Applied from one side of a double-barrelled micropipette, SA-TES increases the amplitude of iontophoretically elicited ACh potentials. The potentiation of the effects of ACh by SA-TES does not involve changes in either the activity of the ACh esterase or the input resistance of the muscle membrane. For depolarizations of frog sartorius muscle, dose-response relationships obtained for ACh concentrations from 0.5 to 20 microM indicate that SA-TES increases the apparent affinity of ACh by a factor of 3. SA-TES exerts an "accelerating' effect on the responses elicited by bath-applied ACh; i.e., it increases the rate of depolarization when ACh is added to the bath and the rate of repolarization upon washing out. These effects are particularly marked in preparations treated with neostigmine (3 microM). SA-TES does not potentiate the depolarizing action of agonists which do not contain an ester group. Moreover, the time course of the responses elicited by these compounds is not influenced by SA-TES. SA-TES fails to influence significantly the effects of the neurally released transmitter. Only a 10% increase in the average amplitude of the endplate potentials was observed. SA hydrolyzes in about 30 min at room temperature; however the SA-TES solution retains its activity for several weeks. Succinate is inactive, and so is SA in Ringer buffered with phosphate. The SA-TES solution contains seven succinyl-TES derivatives, which were separated by ion-exchange chromatography and paper chromatography. At concentrations between 1 to 150 microM, these succinyl-TES derivatives affected the ACh-induced contraction of frog rectus abdominus muscle. The most abundant derivative potentiated the action of high doses of ACh, but was inhibitory at lower ones. The other derivatives were mostly inhibitory. These results are discussed in terms of two hypotheses. One postulates the presence of a diffusion barrier formed by groups that bind ACh and are saturated by SA-TES. The other assumes that SA-TES acts directly on the ACh receptor exerting its potentiating effect through a cooperative mechanism. 相似文献
8.
Maggi R Moretti R Marelli M Pimpinelli F Motta M 《International journal of oncology》1995,6(6):1231-1236
Recent evidence suggests a direct antiproliferative effect of LHRH agonists on the prostatic carcinoma cell line LNCaP. In the present study the possible presence of a LHRH degrading activity (LHRH-DA) in soluble fractions of LNCaP cell homogenates has been investigated. The results obtained show that an LHRH-DA is present in the soluble fraction of LNCaP cells with apparent Km and Vmax values of 31.6 mu M and 4.5 pmol/min/mu g protein respectively. The degradation pattern of LHRH is characterized by two major initial degradation products identified as LHRH 1-5 and LHRH 1-6 fragments. The degradation of the tracer [pGlu-H-3]LHRH, used as a substrate, is inhibited by synthetic unlabelled LHRH (IC50 7.9 mu M) and by several LHRH agonists with different kinetics and potencies; the LHRH agonist [DSer-(tBu)(6),Gly(10)-Aza]LHRH was the most potent blocker of LHRH-DA present in LNCaP cells; this enzymatic activity is also inhibited in a dose dependent manner by somatostatin, TRH, bacitracin and dithiothreitol. The LHRH-DA present in the soluble fraction of LNCaP cells does not seem to be modified by the deprivation of steroids from the culture medium, In conclusion, the presence in LNCaP cells of a soluble peptidase able to degrade LHRH might reinforce the possibility that the prostate is a target for the action of LHRH and of LHRH analogs. 相似文献
9.
M N Boia L P da Motta M D Salazar M P Mutis R B Coutinho J R Coura 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1999,15(3):497-504
A cross-sectional study was performed on the residents of one in every ten households in the town of Novo Air?o, in the northern meso-region of the State of Amazonas, 250 kilometers from Manaus by riverboat. A family cluster sample of 89 dwellings was studied. A stool sample was requested from each of the inhabitants for examination using the Lutz sedimentation and Baermann-Moraes-Coutinho techniques, and blood was taken by venous puncture for Trypanosoma cruzi Elisa antibody testing and immunofluorescence. From a total of 316 stool samples, 87.6% had one or more parasites: Ascaris lumbricoides (35.1%), Entamoeba histolytica (29.1%), Giardia lamblia (17.4%), and other parasites with lower prevalence rates. These results were directly correlated with lack of sanitation and clean water supply. Of the 346 sera examined, 16 (4.6%) were reactive to T. cruzi antibodies, but only three showed a correlation between this result and human contact with wild triatomines, known locally as "piassava lice". 相似文献
10.
Testa T Nahum MA Spinelli E Carbone E Flocchini GP Motta G 《Annali italiani di chirurgia》1999,70(6):829-830
Will Rogers phenomenon affects survival statistics applied to clinical research and could determine a misreading of results. Stage migration due to new methods of diagnostic imaging and staging invasive procedures could improve actuarial survival in each stage. TNM System is impaired when survival rates come from different inhomogeneous countries, regions and eras. Randomized trials suffer this fallacious phenomenon when staging depends on the different treatments which are to be evaluated. 相似文献