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61.
Administration of anti-D immunoglobulin to D- women after delivery of a D+ infant has dramatically reduced the number of immunised women and cases of haemolytic disease of the fetus and newborn. The use of monoclonal anti-D might alleviate some of the pressures on maintaining adequate supplies of plasma sourced anti-D. Two human monoclonal antibodies, BRAD-3 (IgG1) and BRAD-5 (IgG3), with proven activity in in vitro functional (immunological) assays with cells bearing IgG Fc receptors (Fc gamma R) were selected for clinical studies. They were prepared by purification of IgG secreted by culture of the Epstein-Barr virus-transformed B cell lines in hollow fibre bioreactors. The clearance of D+ red cells injected into D- subjects was accelerated by prior injection of the monoclonal antibodies, both individually and blended (3:1, BRAD-5: BRAD-3). The subjects were protected from Rh D immunisation. A large multicentre study evaluated the BRAD-3/5 blend for its ability to prevent Rh D immunisation in 95 D- subjects given 400 micrograms i.m. 24 hours after injection of 5 ml D+ red cells. Challenge injections of D+ red cells alone were given 24 and 36 weeks later, and blood samples were taken every 4 weeks from the subjects throughout the study for detection of anti-D responses. There was one definite and one possible failure of protection; in one subject the plasma anti-D level rose from week 12 onwards, and in another individual rapid seroconversion was observed at week 28. Considering the relatively large dose of red cells and the number of subjects studied, it was concluded that the failure rate was much lower than in routine Rh D prophylaxis. The responder rate was 13% by week 36 and 24% by week 48. The low percentage of responders and the modest levels of endogenous anti-D produced suggested that administration of monoclonal anti-D had induced long-term specific suppression of anti-D responses in these subjects. The most likely mechanism of action was considered to be inhibition of B cells resulting from co-crosslinking antigen receptors with inhibitory Fc gamma R when the B cells contacted red cells that had bound passive anti-D.  相似文献   
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A preliminary study of reaction time in schizophrenics   总被引:1,自引:0,他引:1  
The aim of this study was to make a preliminary study of auditory reaction time (ART) and its significance in cases of schizophrenia. It was found that ART is significantly affected and prolonged in schizophrenia as compared to normal healthy controls (P less than 0.001) when the stimulus is presented to both ears or either car separately. Distractability was higher in schizophrenics as compared to adult controls (P less than 0.001). There was no significant difference in ART within the patient group when the stimulus was presented to the right ear or left ear (P greater than 0.05). There was no significant difference between ART of male and female schizophrenics (P greater than 0.05).  相似文献   
65.
Interobserver variability in neonatal cranial ultrasonography   总被引:1,自引:0,他引:1  
The reliability of cranial ultrasound diagnosis in the premature neonate was examined using data from an ongoing multicentre study of the epidemiology and long-term consequences of neonatal brain haemorrhage. First week ultrasound films (obtained at 4 hours, 24 hours and 7 days) from 60 study subjects were randomly selected for independent review by two groups of experienced interpreters, and results were recorded separately for observations (i.e. presence or absence of an abnormal echodense area on a film) and interpretations (i.e. presence or absence of haemorrhage or ventricular dilatation) in each hemisphere. Because of deaths in the first week of life, the total number of films examined was 138. Concordance on the presence or absence of an abnormal echodensity was examined for each individual film for three areas of interest: the germinal matrix, the ventricles and the parenchyma. Concordance on the presence or absence of haemorrhage or ventricular dilatation was examined only for the seventh-day film, or the final film prior to death. Finally, concordance was analysed with the diagnostic interpretations grouped into categories thought to differ prognostically for long-term outcome. In general, concordance was poorest for germinal matrix lesions and best for parenchymal lesions. Concordance was lower for observations made on each individual film than it was for interpretation of the final film in each case. Fifty-five of 60 cases (92%) were assigned to the same major prognostic category by both readers. Ultrasound review conferences were held periodically and there was evidence that concordance in ultrasound reading and interpretation improved during the course of the study.  相似文献   
66.
In an attempt to ascertain the pharmacological basis of the use of the marketed traditional drug Taverniera abyssinica A. Rich. (Amharic name Dingetegna), crude extracts as well as purified substances of this plant were tested for their antipyretic and analgesic properties. Antipyretic activity was determined on rats made hyperthermic by yeast injection and analgesic activity was determined by the hot plate, as well as the acetic acid induced writhing, methods. The study showed that the plant possesses significant antipyretic and analgesic activities.  相似文献   
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Bladder cancer is one of the malignancies encountered frequently in urological practice. Since the three main treatment modalities (surgery, chemotherapy and radiotherapy) may be used alone or together, there are many treatment options. In this paper the current approaches in the treatment of bladder tumours are reviewed and the policy in Marmara University Hospital is described.  相似文献   
69.
OBJECTIVE: Respiratory scleroma (RS) is a progressive, chronic, granulomatous disease caused by Klebsiella rhinoscleromatis. There is only one report of RS association with HLA-DQ3. In this study, molecular association of HLA class II and RS was determined. STUDY DESIGN AND SETTING: Nine RS patients and 163 healthy controls were compared. DQA1, DQB1, and DRB1 loci were typed. RESULTS: Statistical analysis demonstrated association between DQB1*0301 and susceptibility to RS (P(c) = 0.004). Haplotype analysis showed an association of DQA1*03011-DQB1*0301 (P = 1.21E-19) and DRB1*0407-DQA1*03011-DQB1*0301 (P = 0.0002). CONCLUSIONS: Results established that DQA1*03011-DQB1*0301 haplotype is a strong risk factor for development of RS.  相似文献   
70.
Susceptibility to autologous and heterologous neutralization of primary human immunodeficiency virus (HIV)-1 isolates belonging to subtype B, to the B'-variant of subtype B or to subtype F from infected individuals residing in Rio de Janeiro was assayed. A lower infectivity of the B'- and F isolates when compared to the classical B-subtype HIV-1 isolates was observed. Comparisons of neutralization susceptibilities were carried out for 19 B-subtype, 11 B'-variant and two F-subtype HIV-1 isolates with plasma from autologous and heterologous samples. Frequency of autologous neutralization was slightly lower for B-subtype isolates in comparison to B'-variant isolates. Heterologous intra-subtype neutralization was significantly lower for B-subtype than for the B'-variant or the F-subtype isolates. While B-subtype isolates were neutralized by most anti-F-subtype plasma, F-subtype isolates, although most susceptible to F-subtype antibodies, were highly susceptible to neutralization by anti-B-subtype antibodies. Cross-neutralization for B'-variant and B-subtype isolates was not as extensive as observed for B- and F-subtype isolates. However, the results presented indicate a quite extensive cross-neutralization between Brazilian HIV-1 isolates.  相似文献   
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