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31.
The Modality Specificity of the Slow Negative Wave 总被引:1,自引:0,他引:1
Event-related potentials were recorded in a simple reaction time task using a 3-sec interval between S1 and S2. The sensory modalities of S1 and S2 were varied across 4 conditions to yield all possible combinations of tones and flashes. A negative component which peaked between 600 and 800 msec after S1 was specific in scalp distribution to the modality of S1 but not S2. It was concluded that this negative component is a response to S1 and not related to processes associated with anticipation of S2. A slow negative shift which peaked at S2 was largest at the vertex in all conditions, suggesting its motor origin. A trend for the latter activity to be more negative in posterior recordings when S2 was visual than auditory leaves open the possibility that the terminal CNV is a combination of motor activities and anticipation of the sensory modality of S2. 相似文献
32.
C. Garcia Castro J. M. Gonzalez-Posada V. Castro Lopez-Tarruella E. C. Salido Ruiz 《Diagnostic cytopathology》1993,9(2):174-178
We have analyzed 245 transplant aspirative cytologies (TACs) from 96 renal allograft patients. TACs were divided in two chronological groups: Early (TACs performed during the first 3-mo post-transplantation) and late (TACs performed after the third month post-transplantation), in order to assess the effect of allograft tolerance on TAC features. Both morphological and immunocytochemical aspects were evaluated, including CD4, CD8, IL2-R, and HLA-DR immunolabeling. A final diagnosis for each case of allograft dysfunction was achieved by other independent diagnostic means. Four diagnostic groups were considered in the present study: acute rejection (AR), chronic rejection (CR), acute tubular necrosis (ATN), and Cyclosporin A toxicity (CsA-T). In addition, a control group (C) was established from patients with stable allograft function. We found that immunocytochemical analysis of TACs is particularly helpful in the diagnosis of late allograft dysfunction, a time period when the simple cytological study of renal infiltrate is not informative enough to help take therapeutic decisions. 相似文献
33.
早期干预对高危儿智能发育影响的研究 总被引:1,自引:0,他引:1
周宇芳 《中国优生与遗传杂志》2008,16(4):100-101
目的探讨定期随访高危儿,进行早期发育评价及干预,对高危儿智能发育的影响。方法将82例高危儿随机分成干预组42例和常规组40例,干预组接受早期干预,两组患儿定期随访,以中国婴幼儿发育量表(CDCC)和《Ge-sell发育诊断量表》进行智能发育评估。结果3、6、9月龄时干预组患儿智力发育指数(MD I)和运动发育指数(PD I)均显著高于常规组;1岁时Gesell智能检查,干预组除大运动能区与常规组有显著性差异外(P〈0.05),其他四大能区均存在非常显著性差异(P〈0.01)。结论早期干预可促进高危儿的智能发育,改善其预后。 相似文献
34.
Kerstin Eberhardt MD PhD Britt-Marie Larsson Social worker Kerstin Nived Social worker 《Patient education and counseling》1993,20(2-3):93-100
We report the interaction of RA and psychological factors over 2 years in a group of 89 patients with newly established disease. Short-time outcome regarding physical features was fairly good. Disease activity decreased, and disability evaluated by HAQ remained at a low level. Psychological distress as measured by the depression and anxiety subscales of SCL 90 (Symptom Check List) was not very pronounced and not related to disease state factors. A slight decrease of anxiety was recorded after 2 years. A new adjustment test was applied. It contained 13 items focused mainly on negative illness effects such as loss of independence, feelings of guilt, and change of social and leisure time activities. Three factors (regret of lost life values, dysphoric mood, and acceptance) explained 48% of the variance of the 13 items. The validity of the test was acceptable. The patients' degree of adjustment changed slowly or not at all during the 2 years. 相似文献
35.
Jean Valmier Michel Simonneau Sylvie Boisseau 《Pflügers Archiv : European journal of physiology》1989,414(3):360-368
The electrophysiological properties of a subset of dorsal root ganglion (DRG) neurons microdissected from 12-day-old (E12) mouse embryos and acutely isolated were analyzed as soon as 3 after their isolation. Two classes of neurons were defined according to their mean diameter. The larger diameter class was examined in this study. They display uniform cytoskeletal properties with co-expression of vimentin and neurofilament triplet proteins. Patch-clamp methods also revealed a homogeneous and limited repertoire of ionic channels that included (1) a TTX-sensitive Na+ current whose properties are similar to that reported in mature mammalian neurons, and (2) two types of K+ currents that can be compared with the delayed rectifier (I
k
) and the transient (I
a) potassium currents found in other mammalian preparations. It may be possible to use this in vitro model to examine the development of new types of currents, such as Ca2+ currents during neuronal growth and differentiation. 相似文献
36.
Salvatore Battaglia Giuseppe Barbolini Annibale R. Botticelli 《Virchows Archiv : an international journal of pathology》1979,382(3):245-259
Summary This study was performed in order to elucidate some of the problems of incidence, morphology and natural history concerned with Stage A prostatic cancer or prostatic microcarcinoma (PMC).The prostates of 100 patients, treated by subtotal prostatectomy for benign prostatic hyperplasia (BPH), were studied by comparing both routine and step-section techniques. The incidence of PMC was 41% by the former and 86% by the latter technique. Assessment of the size of PMC, as measured by the sum of the two main diameters, resulted in three groups: A1, A2, A3. The last of these may represent a frankly malignant condition, judged by size and the histological appearance. Radical prostatectomy is strongly suggested as appropriate therapy for this group.Supported in part by a Grant from the Ministry of Education (art. 286 T.U., 1977/78) 相似文献
37.
Dr. W. Hofmann Th. Rommel Th. Schaupp F. Seuter J. A. Rossner F. M. Hecht G. Mall 《Virchows Archiv : an international journal of pathology》1980,385(2):151-168
Zusammenfassung In unserer ultrastrukturell durchgeführten Studie wurden Thromben in der Arteria carotis communis von Ratten nach einer zuerst von Meng und Seuter (1977) beschriebenen Methode experimentell erzeugt. Induktion der Thrombusbildung erfolgte in vivo durch Unterkühlung eines kleinen Gefäßabschnittes unter konstantem Druck und kurzfristiger Stase. Eine Änderung des Blutflusses wurde durch einen Silberclip erzeugt. Die geschädigten Gefäßsegmente einschließlich der Thromben bzw. deren Vorstufen wurden nach 5, 10, 30 min und 1, 4 und 24 h nach der Thrombosestimulation entnommen und fixiert. Semidünnschnitte und Ultradünnschnitte wurden im Licht- und Elektronenmikroskop morphologisch untersucht.Den Transformationsvorgängen im Thrombus konnten exakte Zeitmarken zugeordnet werden. Als wichtigstes histopathologisches Merkmal für die Altersbestimmung arterieller Thromben in der Frühphase der Thrombogenese werteten wir die Querstreifung der Fibrinfasern. Diese trat bereits nach 5 min auf, erreichte nach 30 min ein Maximum und verschwand als Folge der zunehmenden Verdichtung der Fasern nach einer Stunde. Nach 4 h sahen wir eine weitgehende Retraktion der Fibrinfasern, die nach 24 h zur Bildung des Fibrinfasergerüstes mit Einmauerung korpuskulärer Elemente führte. Überdies beobachteten wir zwei Thrombocytenaggregate von differenter Struktur. Wir unterschieden ein fibrinarmes Aggregat, in dem die Thrombocyten dichtgepackt und pseudopodienreich erschienen von einem thrombocytenarmen Aggregat mit reichlich interponierten Fibrinfasern. Die nach 5 min im Zentrum des Thrombus auftretende Agglutination der Plättchen im thrombocytenreichen Aggregat führte nach 30 min zur Thrombocytorrhexis und ergab daher einen weiteren Anhalt für die Altersbestimmung des Coagulum. Der entstandene celluläre Abraum stimulierte mononucleäre Zellen und Leukocyten zur Phagocytose. Daher sahen wir nach 4 h eine massive Leukocytose als Folge der frühen Thrombocytorrhexis. Nach 24 h war die viscöse Metamorphose im fibrinreichen und fibrinararmen Aggregat weitgehend abgeschlossen. Innerhalb des beobachteten Zeitraumes entstand eine Verballung und bizarre Deformierung der Erythrocyten, die bereits nach 5 min vom Zentrum des Thrombus ausging und nach 24 h die Peripherie erreichte. Eine Hämolyse der Erythrocyten war nach dieser Zeit noch nicht erkennbar.
Evolution in the early changes in the establishment of arterial thrombi
Summary Ultrastructural studies of thrombi were carried out on the common carotid artery of the rat using a method first described by Meng and Seuter (1977). Induction of thrombus formation in vivo was achieved by chilling of a small vessel segment under constant pressure and short-termed stasis. Disturbance of the blood flow was produced by a silver clip. The damaged vessel segments with the thrombotic deposits were removed 5, 10, 30 min, and 1, 4 and 24 h after stimulation of thrombosis. They were fixed and samples were studied as semithin and ultrathin sections morphologically using light and electronmicroscopy.In the maturation of thrombi exact time intervals could be determined. The most important histopathological characteristics for age determination of arterial thrombi in the early period of thrombogenesis were the cross stripes of fibrin fibres. They appeared after 5 min, reaching a maximum after 10 min and disappeared as a result of increasing fibre density after 1 h. After 4 h nearly complete retraction of fibrin fibres was found which led after 24 h to the formation of a corresponding frame walling in the corpuscular elements. Apart from this aggregation of thrombocytes, which were of two different types were observed, one showing a fibrin-poor aggregate in which the thrombocytes appeared densely packed with numerous pseudopods, and one showing a thrombocyte poor aggregate with abundant interposed fibrin fibres. Agglutination of platelets which occurred in the thrombocyte-rich aggregate in the centre of the thrombus after 5 min led to thrombocytorrhexis after 30 min. The resulting cellular waste stimulated phagocytosis by mononuclear cells and leucocytes. Because of this a massive leucocytosis was found as a result of the early thrombocytorrhexis after 4 h. After 24 h the viscous metamorphosis in the fibrin-rich and in the fibrin-poor aggregate was largely completed. Clumping and deformation of erythrocytes was observed in the middle of the thrombus after 5 min and at the periphery of the thrombus after 24 h. Haemolysis did not occur within this time interval.
Frau Antoni, Herrn Ing. grad. Derks und Herrn Rieger sei für ausgezeichnete technische Assistenz herzlichst gedankt. 相似文献
38.
Matturri L Ottaviani G Lavezzi AM 《Virchows Archiv : an international journal of pathology》2005,447(1):74-80
Cigarette smoking is associated with an increased incidence of atherosclerotic diseases. The aim of this study was to examine the progression of the preatherosclerotic lesions previously observed by us in coronary arteries of fetuses of smoker mothers and in infants with smoker parents. We examined the coronary arteries of 34 infants, aged 1–36 months, and the histological and biological [c-fos, proliferating cell nuclear antigen (PCNA), and apoptosis] features of the early atherosclerotic lesions. In 17 infants (50%), at least one parent smoked, generally more than five cigarettes a day. In 18 cases (53%), we observed variable thickening of the coronary walls from preatherosclerotic lesions to juvenile atherosclerotic plaques, related to parental smoking habit. This morphological progression of the lesions was accompanied by a sequence of biological changes in the smooth muscle cells of the tunica media. We suggest that the oxidants present in the gas phase of the parental cigarette smoke pass through the endothelium and induce at first the c-fos gene activation and subsequently the PCNA positivity, that is, a proliferative process. 相似文献
39.
Joshua S. Newton Jin Li Zhi-Qiang Ning Diana E. Schoendorf John D. Norton John J. Murphy 《European journal of immunology》1996,26(4):811-816
B lymphocytes are activated following antigen stimulation of the B cell receptor but require co-stimulation with accessory molecules provided by interleukin (IL)-4/CD40 ligand for cell cycle progression and proliferation. By analyzing a panel of 11 early response genes induced by cross-linking of surface immunoglobulin, we show that CD40 signaling alone induces only 2 genes, c-myc together with an anonymous gene, 3L3, and that these are distinct from the set of genes induced in response to IL-4. Co-stimulation with the proliferative combination of anti-μ, IL-4 + CD40 signaling led to a fourfold enhancement of egr-2/krox20 expression over that seen with anti-μ alone. Egr-2 expression/activity was selectively inhibited by the immunosuppressive drug cyclosporin A, and antisense oligonucleotide blockade of Egr-2 activity elicited a dose-dependent inhibition of B cell proliferation. Taken together, these observations show that the early gene regulatory programs coupled to different surface receptors on B cells are largely distinct from each other, but that certain genes, exemplified by egr-2, may represent a point of convergence in the integration of different signaling pathways into the B cell proliferative response. 相似文献
40.
《Journal of the Academy of Nutrition and Dietetics》2021,121(4):678-687.e1
BackgroundNationally, approximately one-third of early childhood education centers participating in the Child and Adult Care Food Program (CACFP) are independently owned and operated (ie, not owned by a corporation, not affiliated with Head Start, and with no food program sponsor). Independent providers are less likely to meet CACFP standards and best practices and would benefit from additional support and technical assistance.ObjectiveTo explore independent early childhood education center key informants’ (KIs) (ie, directors or relevant staff) perspectives on implementing the revised CACFP standards.DesignFollowing qualitative exploratory design, semistructured, in-depth, telephone interviews were conducted with KIs individually.Participants/settingIn summer 2018, 30 randomly sampled KIs from independent CACFP-participating early childhood education centers serving children ages 2 to 5 years nationwide were interviewed. Participants were sampled from respondents to a previously completed nationwide survey of providers.Main outcomesKIs’ perspectives on the CACFP program and revised meal pattern standard implementation.Analysis performedAfter audio recordings were professionally transcribed and reviewed, constant comparative analysis was conducted using Atlas.ti v8 qualitative software (Atlas.ti. version 8 for Windows, 2018, Scientific Software Development GmbH).ResultsKIs indicated that program benefits (eg, health and nutrition benefits, reimbursement, guidelines, and training) outweighed challenges experienced. Challenges associated with revised CACFP standards implementation (eg, availability or acceptability of new, creditable foods) were impacted by enhanced CACFP standards status, reported revised standards, and availability or utilization of outside support. KIs desired more contact with their state representative. KIs found the training and technical assistance on the revised standards useful and suggestions to enhance future training and technical assistance (eg, increasing accessibility, training resources, and audience-specific training).ConclusionsOverall, KIs desired additional resources, training, and increased communication from CACFP state representatives specific to CACFP-approved and reimbursable products, menu ideas, recipes, and cooking demonstrations. The present study suggests that a more tailored training and technical assistance approach is necessary as reported benefits, challenges, and program needs varied based on state-enhanced CACFP standards, reported familiarity with the revised meal pattern, and reported outside support. 相似文献