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21.
Antenatal administration of glucocorticoids is often used to facilitate fetal lung maturation in cases of prematurity; however, the effects of betamethasone on maternal immune function have not been established. Therefore maternal immune function was assessed with the use of in vitro techniques. Transient and incomplete suppression of the proliferative response to the T-cell mitogen phytohemagglutinin was demonstrated as early as 24 hours after administration of betamethasone. The magnitude and duration of suppression showed a corresponding increase with advancing gestational age, but these effects were not cumulative and were always short-lived (less than 72 hours). No such suppression of the B-cell mitogen lipopolysaccharide was detected. The nonspecific cellular resistance to infection of maternal monocytes was determined through coincubation with the facultative intracellular pathogen Listeria monocytogenes. Increased phagocytic activity with a normal bactericidal effect was measured in the cell preparations obtained from recipients versus nonrecipients of betamethasone. Taken together, these findings clearly show that both specific and nonspecific immune function are intact in the preterm gravid woman after administration of betamethasone and should allay concerns over its use for reasons of infection control alone. 相似文献
22.
A human amphotropic retrovirus receptor is a second member of the gibbon ape leukemia virus receptor family. 总被引:30,自引:3,他引:27
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M van Zeijl S V Johann E Closs J Cunningham R Eddy T B Shows B O'Hara 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(3):1168-1172
Retrovirus infection is initiated by binding of the viral envelope glycoprotein to a cell-surface receptor. The envelope proteins of type C retroviruses of mammals demonstrate similarities in structural organization and protein sequence. These similarities suggest the possibility that retroviruses from different interference groups might use related proteins as receptors, despite the absence of any relationship between retrovirus receptors isolated to date. To investigate this possibility, we have identified a human cDNA clone encoding a protein closely related to the receptor for gibbon ape leukemia virus and have found that it functions as the receptor for the amphotropic group of murine retroviruses. Expression of this protein (GLVR-2) is likely to be a requirement for infection of human cells by amphotropic retroviral vectors for purposes of gene therapy. 相似文献
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T. Hickish P. Serafinowski D. Cunningham A. Oza E. Dorland I. Judson B. C. Millar T. A. Lister A. Roldan 《British journal of cancer》1993,67(1):139-143
2''-Chlorodeoxyadenosine (2CDA) is a purine analogue selectively active against both resting and dividing lymphoid cells. Twenty-one patients with a variety of previously treated lymphoid malignancies received a total of 41 courses of 2CDA (0.1-0.15 mg/kg/day over 7 days continuous intravenous infusion) on compassionate grounds. The profile of the patient population was as follows: low grade non-Hodgkin''s lymphoma (NHL) = 8, intermediate grade NHL = 2, transformed (intermediate grade NHL) = 6, Hodgkin''s disease = 1, lymphoplasmacytoid NHL = 3 and lymphoblastic NHL = 1. The overall response rate was 53%, with three patients attaining complete remission (CR) and eight partial remission (PR). Three of 16 patients with primary resistant or resistant recurrent disease entered either CR (1) or PR (2). Ten patients had no response or progressive disease. The latter group was comprised of patients who had extensively pre-treated lymphoplasmacytoid tumours and/or poor performance status (WHO grades 2-4). The median duration of response is 6 months (range 1 to 12 months). Treatment was well tolerated and the chief toxicities were leucopenia and thrombocytopenia which were most pronounced when there was bone marrow involvement. As a result of dose limiting myelotoxicity, a dose escalation to 0.15 mg/kg/day was possible on just three occasions. These data confirm other reports of the activity of 2CDA in low grade NHL and indicate it may have activity in Hodgkin''s disease. There was no demonstrable activity in poor performance status patients or those with extensively pre-treated lymphoplasmacytoid tumours. 相似文献
25.
BACKGROUND CONTEXT: Symptomatic spinal epidural lipomatosis (SEL), a rare cause of spinal cord compression, has most often been associated with exogenous steroid use. PURPOSE: Identify four associations with SEL, correlate the associated groups with level of disease and compare treatment with outcome data in these groups. STUDY DESIGN/SETTING: Case reports of three patients and analysis of 104 cases from the literature. PATIENT SAMPLE: Three patients from the senior author's practice. OUTCOME MEASURES: Not applicable. METHODS: The authors report three new cases of SEL not associated with steroid use. They review all available English literature and present a table of all 104 reported cases. RESULTS: The clinical course of three new patients is reported. CONCLUSIONS: Associated conditions are exogenous steroid use, obesity, endogenous steroid excess, and some remain idiopathic. Although SEL is a rare condition, our review of the literature reveals many more reported cases than previously thought. With increased awareness of this condition and improved imaging techniques, further studies of this disease should be undertaken. 相似文献
26.
R A Clary M J Cunningham R D Eavey 《The Annals of otology, rhinology, and laryngology》1992,101(7):598-600
The accuracy of computed tomography (CT) in distinguishing an abscess from cellulitis in children who present with orbital manifestations of paranasal sinus infection remains in question. In this 10-year retrospective study, CT results are compared with surgical findings in 19 patients with orbital complications who underwent surgical exploration within 24 hours of their CT scans. Fifteen of the 19 CT scan interpretations indicated abscesses that were verified intraoperatively. Two patients had negative surgical explorations despite CT interpretations predicting abscesses. An abscess was also surgically documented in 1 of 2 patients whose preoperative scans indicated cellulitis alone. We conclude that the correlation between radiologic and operative findings in 16 of these 19 cases, although not absolute, does substantiate the use of CT scanning as a therapeutic guide in children presenting with orbital disease secondary to paranasal sinusitis. 相似文献
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Recent evidence suggests that the putative dopamine (DA) autoreceptor antagonists, (+)-AJ 76 and (+)-UH 232, share some neurochemical and behavioral effects with both psychostimulants and neuroleptics. The ability of (+)-AJ 76 and (+)-UH 232 to mimic or antagonize the stimulus effects of cocaine was investigated in rats trained to discriminate 5 mg/kg (N=8) or 10 mg/kg (N=8) of cocaine from saline in a two-lever, water-reinforced, drug discrimination task. In the cocaine (10 mg/kg) group, administration of (+)-AJ 76 (2.5–20 mg/kg) engendered only a partial substitution for cocaine (maximum 60% cocaine-lever responses). Given in combination with cocaine (10 mg/kg), (+)-AJ 76 (2.5–40 mg/kg) did not significantly attenuate the cocaine cue. A fixed dose of (+)-AJ 76 (2.5 or 10 mg/kg) plus various doses of cocaine (1.25–5 mg/kg) did not alter the cocaine dose-response curve. (+)-UH 232 (2–16 mg/kg) produced primarily saline-appropriate responding in rats trained to discriminate 5 mg/kg of cocaine and was unable to block the interoceptive cocaine state when given in combination with cocaine (5 mg/kg). (+)-UH 232 (2 or 8 mg/kg) also did not alter the cocaine dose-response curve. These results suggest that (+)-AJ 76 and (+)-UH 232 elicit only weak or no cocaine-like stimulus effects and, unlike neuroleptics, do not attenuate the cocaine cue. 相似文献
30.
V R Bohman R W Stettler B B Little G D Wendel L J Sutor F G Cunningham 《Obstetrics and gynecology》1992,80(4):609-613
OBJECTIVE: To better understand hepatitis C viropathies and seroprevalence by performing an epidemiologic analysis of pregnant women seropositive for antibody against hepatitis C. METHODS: We studied 1013 consecutive obstetric patients at Parkland Memorial Hospital who gave informed consent for detailed interviews and serotesting. Sera were analyzed for antibody to the hepatitis C virus using both C100-3 and RIBA-4 assays. Neonatal assessment was carried out in the immediate postpartum period. RESULTS: Hepatitis C antibody was detected in 2.28% (N = 23) of the 1005 women in whom analysis was completed. Factors associated with seropositivity included intravenous (IV) drug use, sexually transmitted diseases, hepatitis B infection, maternal age greater than 22.5 years, increased parity (eg, greater than 2.1), history of transfusion, and three or more different lifetime sexual partners or a sexual partner who used IV drugs. Maternal and neonatal outcome was not different between hepatitis C antibody-positive and -negative groups. CONCLUSIONS: Epidemiologic data are consistent with sexual and parenteral modes of transmission. Women with hepatitis C antibody did not have excessive perinatal complications compared with antibody-negative women. A model protocol and cost analysis for screening pregnant women for hepatitis C infection are presented. However, routine screening for hepatitis C is not advocated. 相似文献