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991.
Goldstein NS Ferkowicz M Kestin L Chmielewski GW Welsh RJ 《American journal of clinical pathology》2003,120(5):720-724
We studied 31 T1 N0 M0 peripheral adenocarcinomas diagnosed by wedge resection and treated by lobectomy. Factors recorded were pleural surface-based, gross cut-surface, and microscopic margin distances; morphologic features of the adenocarcinomas; microscopic extension distance of beyond gross perimeter of neoplasm; and presence of residual adenocarcinoma in the lobectomy specimen. All staple-line margins in the wedge and lobectomy specimens underwent complete histologic examination. The mean pleural surface-based, gross cut-surface, and microscopic margin distances in wedge resections were 13.1, 4.1, and 2.3 mm, respectively. The mean microscopic wedge resection margin distance was 11 mm smaller than the pleural surface-based measured margin. The mean microscopic lepidic growth beyond the gross perimeter of the neoplasm was 7.4 mm. Fourteen lobectomy specimens (45%) included adenocarcinoma. The mean microscopic wedge resection specimen margin distances in cases with and without residual adenocarcinoma in the lobectomy specimens were 0.7 and 2.4 mm, respectively (P < .001). Incomplete excision may contribute to higher locoregional recurrence rates following limited resection surgery. Two processes affected wedge resection margin distances: stapling-induced parenchymal stretching, resulting in overestimation of pleural surface-based distances, and microscopic extension of adenocarcinoma beyond the gross perimeter of the neoplasm. 相似文献
992.
Maintenance of B lymphocyte-related clones in the cerebrospinal fluid of multiple sclerosis patients
Colombo M Dono M Gazzola P Chiorazzi N Mancardi G Ferrarini M 《European journal of immunology》2003,33(12):3433-3438
A longitudinal study of Ig V gene segments utilized by B cells from the cerebrospinal fluid (CSF) of two patients with multiple sclerosis (MS) was carried out using RT-PCR methodologies. One patient with a relapsing-remitting (RR)-MS was investigated at onset and at relapse, 1 year later. A patient with secondary-progressive (SP)-MS was tested 9 and 13 years after disease onset. Sequence analyses of V(H)DJ(H) segments bearing V(H)3 and V(H)4 that were obtained from Cgamma cDNA genes demonstrated a substantial proportion of shared clones in the samples taken at different times; these clones were identical or closely related, i.e. had the same third complementary determining region (CDR) of the H chain variable region gene (HCDR3) with different mutations in the V(H) segment. Collectively, these data demonstrate that in MS patients there is a strong selective pressure, which could be exerted by antigen (or autoantigen) stimulation, for the maintenance and partial diversification of certain V(H)DJ(H) Cgamma sequences. 相似文献
993.
This paper reports evidence of the existence of multiple and distinct visual memory processes in a memory search task in which a divided field stimulus presentation was used at study (Experiments 1-3) and either a foveal (Experiments 1 and 2) or a lateralized (Experiment 3) stimulus presentation was used at test. These memory processes can be distinguished on the basis of (1) whether or not they are hemispherically organized; and (2) the locus of their underlying brain activity, as evidenced by the scalp distribution of the event-related brain potentials and by the localization of the event-related optical signal that accompany them. These memory effects are discussed in the context of visual form memory. 相似文献
994.
995.
Bartholow BD Pearson M Sher KJ Wieman LC Fabiani M Gratton G 《Biological psychology》2003,64(1-2):167-190
The present study sought to examine acute effects of alcohol on cognitive processing and performance within the context of two prominent theories of alcohol's effects; namely, that alcohol restricts the focus of attention (e.g. Steele and Josephs, 1990. Journal of Abnormal Psychology, 97, 196-205) and that alcohol impairs response inhibition (e.g. Fillmore and Vogel-Sprott, 1999. Experimental and Clinical Psychopharmacology, 7, 49-55; Fillmore and Vogel-Sprott, 2000. Journal of Studies on Alcohol, 61, 239-246). Forty-five participants were randomly assigned to receive either a placebo level of alcohol (0.04 g/kg), a moderate dose (0.40 g/kg), or a higher dose (0.80 g/kg). Brain electrical activity (ERPs) and behavioral responses (reaction time and accuracy) were measured while participants performed a modified flanker task, in which a target letter was flanked by response-compatible or response-incompatible letters. Analyses of behavioral data showed that alcohol increased response competition in accuracy but not response times, suggesting that alcohol influences response selection more than attentional processes per se. This finding is in-line with predictions derived from the response inhibition model. ERP latency data provided mixed support for both models. ERP amplitude data showed that the high dose of alcohol primarily influenced a mostly frontal negativity in the ERP, present on both correct and incorrect response trials. Differences in self-reported susceptibility to alcohol were most evident in the amplitude of the P3 component. Findings are discussed in terms of the differential effects of acute dose and susceptibility on information processing. 相似文献
996.
Actinobacillus actinomycetemcomitans serotype b lipopolysaccharide mediates coaggregation with Fusobacterium nucleatum 下载免费PDF全文
Purified Actinobacillus actinomycetemcomitans serotype b lipopolysaccharide (LPS) was found to be able to bind Fusobacterium nucleatum cells and to inhibit binding of F. nucleatum to A. actinomycetemcomitans serotype b. Sugar binding studies showed that the requirements for binding of A. actinomycetemcomitans serotype b LPS to the F. nucleatum lectin are the presence of a metal divalent ion, an axial free hydroxyl group at position 4, and free equatorial hydroxyl groups at positions 3 and 6 of D-galactose, indicating that the beta-N-acetyl-D-galactosamine in the serotype b LPS trisaccharide repeating unit is the monosaccharide residue recognized by the F. nucleatum lectin. These data strongly suggest that A. actinomycetemcomitans serotype b LPS is one of the receptors responsible for the lactose-inhibitable coaggregation of A. actinomycetemcomitans to fusobacteria. 相似文献
997.
998.
Paradoxical sleep deprivation (PSD) for 96 h together with cocaine administration elicits genital reflexes (penile erection [PE] and ejaculation [EJ]) in rats. Our objective was to examine genital reflexes after periods of 24, 48, 72, 96, 120, and 144 h of PSD and during a 4-day recovery period in acute cocaine-administered rats. After 24 h of PSD followed by cocaine administration, animals started to display PE and EJ, peaking in the 96th h of PSD, whereas PE and EJ were absent in control animals. The effects of more than 96 h of PSD decrease genital reflexes as observed after 120 and 144 h. Genital reflexes were present in the recovery periods but diminished gradually during the period evaluated. Even short periods of PSD probably cause supersensitivity of dopamine (DA) receptors and exacerbate the effects of cocaine on dopaminergic pathways to induce frequent PE and EJ. 相似文献
999.
Abdominal compartment syndrome in children: CT findings 总被引:17,自引:0,他引:17
Abdominal compartment syndrome (ACS) is caused by pathological elevation of intra-abdominal pressure (IAP) leading to multiple organ dysfunction syndrome. Since the condition is highly lethal, early diagnosis is imperative. We evaluated the pre-operative abdominal CT scans of three children with proven ACS to identify signs of elevated IAP. Findings common to these patients included narrowing of the inferior vena cava (IVC), direct renal compression or displacement, bowel wall thickening with enhancement and a rounded appearance of the abdomen. The aim of recognising the CT findings in such cases is to plan emergency surgical decompression. Although these findings are not specific for increased IAP, radiologists should be aware of this life-threatening condition and, in the proper clinical setting, should communicate the presence and significance of these findings to the referring clinician. 相似文献
1000.
We present the CT and MRI findings of an 8-day-old infant with an infected cephalhaematoma complicated by skull osteomyelitis, venous sinus thrombosis and left cerebellar haemorrhage. 相似文献