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81.
This paper describes seventeen novel HLA-A locus alleles: A*0106, *0235, *0236, *0237, *1105, *2302, *2303, *24032, *2422, *2424, *2503, *2613, *3007, *3203, *3204, *6809 and *6810. All alleles were identified due to unexpected probe reaction patterns during routine SSOP typing. Exons 2 and 3 of these alleles were subsequently characterized by DNA sequencing. The alleles represent a shuffling of sequence motifs, likely by interallelic conversion, expanding the diversity of the HLA system.  相似文献   
82.
To the Editor: There are a large number of studies addressing the impact of continuing medical education (Davis et al. 1995) and clinical guidelines (Grimshaw & Russell 1993) on changing clinical practice, but comparatively little on the impact of purchasers of health care. There is some evidence that financial incentives and penalties can influence practice (Greco & Eisenberg 1993). It has been suggested that purchasers can play an important role in implementing research findings (Haines & Jones 1994). Indeed, the separation of purchasers and providers has been viewed as an opportunity to use knowledge about effectiveness to improve health services (Dunning et al. 1994). We report a study the aim of which was to explore the impact that a specific brief external intervention might have on a detailed aspect of clinical practice: the use of corticosteroids in preterm labour. The intervention was initiated by public health physicians on behalf of a Health Authority. It formed a part of the Getting Research Into Practice (GRIP) initiative in the old Oxford Health Region, UK.  The administration of corticosteroids to mothers expected to deliver prematurely reduces neonatal mortality and morbidity (Crowley et al. 1990). The first trial which suggested that corticosteroids were effective in this role was published in 1972, and evidence from 12 trials was assembled in a systematic review published in January 1990 (Crowley et al. 1990). Despite the accumulating evidence, in 1991 many women delivering prematurely in the UK and elsewhere were not receiving corticosteroids (Anon 1992;Donaldson 1992). The apparent failure of obstetricians to make full use of this treatment has been cited as an example of the delayed implementation of research findings that can occur in clinical practice (Haines & Jones 1994; Enkin 1996).  相似文献   
83.
Two to three years after infection, a fraction of HIV-1-infected individuals develop serologic activity that neutralizes most viral isolates. Broadly neutralizing antibodies that recognize the HIV-1 envelope protein have been isolated from these patients by single-cell sorting and by neutralization screens. Here, we report a new method for anti-HIV-1 antibody isolation based on capturing single B cells that recognize the HIV-1 envelope protein expressed on the surface of transfected cells. Although far less efficient than soluble protein baits, the cell-based capture method identified antibodies that bind to a new broadly neutralizing epitope in the vicinity of the V3 loop and the CD4-induced site (CD4i). The new epitope is expressed on the cell surface form of the HIV-1 spike, but not on soluble forms of the same envelope protein. Moreover, the new antibodies complement the neutralization spectrum of potent broadly neutralizing anti-CD4 binding site (CD4bs) antibodies obtained from the same individual. Thus, combinations of potent broadly neutralizing antibodies with complementary activity can account for the breadth and potency of naturally arising anti-HIV-1 serologic activity. Therefore, vaccines aimed at eliciting anti-HIV-1 serologic breadth and potency should not be limited to single epitopes.  相似文献   
84.
DNA as a target for drug action   总被引:2,自引:0,他引:2  
  相似文献   
85.
Three cDNA clones encoding a DQ beta and two DR beta polypeptides have been isolated and sequenced from an American black individual expressing a DR2,DQw1 haplotype. The sequences of the cDNA clones are identical to previously described DR and DQ sequences from a DR2,Dw2 cell. The differences between DQw1-associated beta chains from DR2 and DR1 haplotypes is substantial, although a DQw1-specific sequence can be identified. The identical DQ and DR beta sequences found in unrelated individuals from different racial backgrounds suggests that class II structural polymorphism within the human population will be limited.  相似文献   
86.
87.
Although the condition is rare, patients with hereditary angioedema often present because of abdominal pain or airway compromise. A 27-year-old woman presented to the emergency department in acute abdominal distress. Identification of the disease in this patient allowed for proper management and avoidance of invasive procedures. Pathophysiology, clinical manifestations, diagnosis, and therapy of hereditary angioedema are discussed.  相似文献   
88.
Test strips recently have become available to measure theophylline levels. One such test strip (AccuLevel) had not been tested in an actual clinical situation with nontechnician personnel. We prospectively evaluated the test strip on consecutive emergency department patients, comparing it with the agglutination inhibition method used by our hospital laboratory. Nurses and medics who ran the test were given only a brief demonstration and explanation of the manufacturer's instructions. The 61 test strip levels correlated highly with the laboratory results (r = 0.92, slope = 0.89, y-intercept = 0.99). The test strip results were available in less time (mean of 0.51 hours vs 1.89 hours for the laboratory, P less than .0001). The most accurate readings were obtained by those who ran the test most frequently. Caffeine intake did not influence the test. Cost was significantly lower than charges at local hospitals.  相似文献   
89.
90.
Aim: To describe cardiorespiratory fitness and body mass index (BMI) values in a representative population of 9-year-old Norwegian children in two rural communities and compare present values with previous findings.
Methods: Two hundred and fifty-nine 9-year-old children were invited, and 256 participated in this study. Maximal oxygen uptake was directly measured during a continuous progressive treadmill protocol. Body mass and height were also measured.
Results: The mean ± SD relative maximal oxygen uptake was 52.8 ± 6.5 for boys and 46.9 ± 7.2 mL/kg/min for girls. Eight percent of the boys and 16.8% of the girls were classified as overweight, and 1.6% of the boys and 6.9% of the girls as obese. Mean age, body mass, height and Ponderal index were not significantly different between sexes. Girls had a higher BMI than boys (p = 0.05).
Conclusion: Compared to earlier Norwegian studies, children's BMI values seem to have increased substantially. This increase is most pronounced in girls. When assessing these differences using the PI, this increase is less marked. Comparing maximal oxygen uptake data with that in earlier Nordic studies, there is no evidence that fitness has declined among 9-year olds. However, the limitations of the few earlier studies make reliable comparisons difficult.  相似文献   
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