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991.
Neonatal cerebral white matter injury in preterm infants is associated with culture positive infections and only rarely with metabolic acidosis 总被引:6,自引:0,他引:6
Graham EM Holcroft CJ Rai KK Donohue PK Allen MC 《American journal of obstetrics and gynecology》2004,191(4):1305-1310
OBJECTIVE: Neonatal cerebral white matter injury represents a major precursor for neurological impairment and cerebral palsy. Our objective was to identify risk factors associated with its development. STUDY DESIGN: This retrospective case-control study of all births between 23 and 34 weeks gestation at a single university hospital between May 1994 and September 2001 identified 150 cases with white matter injury characterized by periventricular leukomalacia or ventricular dilatation from white matter atrophy that were chromosomally normal and did not have other congenital anomalies. Cases were matched to controls without brain injury by the next delivery within 7 days of their gestational age. RESULTS: There were small differences between controls and cases in gestational age (27.5 +/- 2.7, 27.4 +/- 2.6 weeks, P = .01) and birth weight (1053 +/- 402, 966 +/- 285 g, P = .002) that were statistically but not clinically significant. There was no difference in the percentage of controls and cases delivered by cesarean (45%, 49%, P = .64). There were no differences between controls and cases in umbilical arterial pH (7.27 +/- 0.11, 7.25 +/- 0.15, P = .19), base excess (-2.1 +/- 2.7, -3.0 +/- 4.1 mmol/L, P = .28), pH less than 7.0 (2/122 [2%], 3/107 [3%], P = 1.0), or base excess less than -12 mmol/L (4/121 [3%], 6/106 [6%], P = .75). The cases had a significant increase in positive blood (19%, 29%, P = .036), cerebrospinal fluid (6%, 17%, P = .002), and tracheal (9%, 22%, P = .003) cultures during the neonatal period. Conditional logistic regression showed a significant association among multiple gestations ( P = .02), intraventricular hemorrhage ( P < .001), and positive tracheal cultures ( P = .02) with cerebral white matter injury. CONCLUSION: Culture-positive infection was associated with an increased risk of cerebral white matter injury in preterm neonates. Intrapartum hypoxia-ischemia as manifested by metabolic acidosis was rarely associated with white matter injury and was not different from the incidence in premature neonates without injury. 相似文献
992.
Priapism, prolonged painful erection of the penis, is a urological emergency. Untreated, the patient can end up with impotence. Various methods have been described for its treatment but the initial management remains conservative. This study presents our experience with the use of sedation followed by an ice-cold saline enema in the management of priapism. 相似文献
993.
Broor S Bhupatiraju AV Broor SL Ghosh D Anand R Rai A Colina R García L Khan B Cristina J 《Archives of virology》2004,149(6):1185-1192
Summary. The degree of genetic variability among Hepatitis C virus strains circulating in India is currently unknown. In order to get insight into this matter, sequence data obtained from the 5 non coding region from 8 patients from New Delhi were compared with sequences from 16 HCV isolates from different geographic locations of India. The phylogenetic analysis of most prevalent genotypes revealed the presence of novel HCV variants in type 1 strains. 相似文献
994.
995.
Multiple distinct sets of stereotyped antigen receptors indicate a role for antigen in promoting chronic lymphocytic leukemia
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Messmer BT Albesiano E Efremov DG Ghiotto F Allen SL Kolitz J Foa R Damle RN Fais F Messmer D Rai KR Ferrarini M Chiorazzi N 《The Journal of experimental medicine》2004,200(4):519-525
Previous studies suggest that the diversity of the expressed variable (V) region repertoire of the immunoglobulin (Ig)H chain of B-CLL cells is restricted. Although limited examples of marked constraint in the primary structure of the H and L chain V regions exist, the possibility that this level of restriction is a general principle in this disease has not been accepted. This report describes five sets of patients, mostly with unmutated or minimally mutated IgV genes, with strikingly similar B cell antigen receptors (BCRs) arising from the use of common H and L chain V region gene segments that share CDR3 structural features such as length, amino acid composition, and unique amino acid residues at recombination junctions. Thus, a much more striking degree of structural restriction of the entire BCR and a much higher frequency of receptor sharing exists among patients than appreciated previously. The data imply that either a significant fraction of B-CLL cells was selected by a limited set of antigenic epitopes at some point in their development and/or that they derive from a distinct B cell subpopulation with limited Ig V region diversity. These shared, stereotyped Ig molecules may be valuable probes for antigen identification and important targets for cross-reactive idiotypic therapy. 相似文献
996.
Kanno Y Kobayashi H Rai T Kanno K Watanabe K Obara K Sato Y 《Internal medicine (Tokyo, Japan)》2004,43(7):620-623
A 49-year-old healthy Japanese woman presented with hemorrhagic diarrhea because of Shiga toxin producing Escherichia coli infection, and then hemolytic uremic syndrome (HUS) developed in the patient. She was successfully treated with continuous hemodiafiltration, plasma exchange, and endotoxin adsorption therapy. An analysis of previous case reports suggests that females aged between 16 and 65 years are at an increased risk of HUS resulting from hemorrhagic colitis. We propose that adult female patients with hemorrhagic colitis should be carefully monitored regardless of their medical history, physical presentation, or laboratory data. 相似文献
997.
998.
Depressed cortical excitability and elevated matrix metalloproteinases in remote brain regions following intracerebral hemorrhage 总被引:1,自引:0,他引:1
The absence of cortical responses to external stimuli is a dubious clinical sign during the first 1-2 days of brain injury. We previously showed that the amplitude of the somatic evoked potential (SEP) in the swine is diminished at the infarct site and perihematomal surround within the first 6 h of collagenase-induced intracerebral hemorrhage (ICH). We now report that this depressed SEP persists during the subchronic (48 h) period of ICH in the swine not only within the injured primary somatosensory (SI) cortex, but also in the contralateral homotopic SI cortex. This impairment of sensory responsiveness was accompanied by increases in various matrix metalloproteinases (MMPs) in different brain regions. By 24 h, a marked rise in MMP-9, an inflammatory marker, was detected in the white matter of the ipsilesional SI and secondary somatosensory cortex (SII), and in the contralesional SI gray matter, as compared to saline-injected controls. A subsequent increase in MMP-9 level was found in the ipsilesional SI and SII gray matter, and in the contralesional SI white matter by 48 h (P<0.05). By 7 days, significant levels of MMP-9 were detected only in the ipsilesional SI white and gray matter tissues. In contrast, the elevation of MMP-2, a marker of degeneration, was delayed until 7 days post-ICH in the ipsilesional SII gray matter. A significant rise in MMP-9 was also noted in CA1 of the ipsilesional and contralesional hemispheres during 1-2 days. Our MMP assay shows that the depressed cortical excitability seen in the contralateral SI cortex is a manifestation of the broad effect of a focal ICH that produces inflammatory and degenerative processes not only in the region adjacent to the focal ICH site, but also in remote regions that are functionally connected to the site of focal ICH. 相似文献
999.
1000.