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1.
Neisseria meningitidis group B (MenB) strains isolated from 1976 to 1987 in Finland in 339 patients with invasive infection were sero/subtyped by whole cell enzyme immunoassay using monoclonal antibodies to class 1 and 2/3 outer membrane proteins. 66.7% of the strains could be serotyped (class 2/3) and 70.2% subtyped (class 1). No single phenotype was clearly predominant. The most common serotypes were 4 (18.6%) and 14 (17.4%) and the most common subtypes P1.16 (20.1%) and P1.2 (12.1%). The Norwegian phenotype B:15:P1.16 was seen only rarely (a total of 18 strains). Strains from Northern Finland did not differ from those from Southern Finland: no single phenotype caused the slight increase seen in the incidence of MenB infections in the end of 1970s in the North.  相似文献   
2.
Efficient target-selected mutagenesis in zebrafish   总被引:21,自引:1,他引:21       下载免费PDF全文
One of the most powerful methods available to assign function to a gene is to inactivate or knockout the gene. Recently,we described the first target-selected knockout in zebrafish. Here,we report on the further improvements of this procedure,resulting in a highly efficient and easy method to do target-selected mutagenesis in zebrafish. A library of 4608 ENU-mutagenized F1 animals was generated and kept as a living stock. The DNA of these animals was screened for mutations in 16 genes by use of CEL-I-mediated heteroduplex cleavage (TILLING) and subsequent resequencing. In total,255 mutations were identified,of which 14 resulted in a premature stop codon,7 in a splice donor/acceptor site mutation,and 119 in an amino acid change. By this method,we potentially knocked out 13 different genes in a few months time. Furthermore,we show that TILLING can be used to detect the full spectrum of ENU-induced mutations in a vertebrate genome with the presence of many naturally occurring polymorphisms.  相似文献   
3.
To investigate central and pulmonary hemodynamics in a standardized normovolemic experimental muscle injury model, 8 anesthetized and mechanically ventilated test pigs were intracavally infused with 100 ml of autologous muscle extract over a period of 100 min; 8 control pigs received Ringer's solution. The cardiac index decreased 20% and the heart rate decreased 10% within 30 min of starting the infusion in the muscle extract group and remained depressed. Mean arterial pressure increased significantly in both groups. The pulmonary capillary wedge pressure and central venous pressure remained relatively unchanged during the 5-hour study. A 2-fold increase in mean pulmonary arterial pressure and a nearly 4-fold increase in the pulmonary vascular resistance index was seen in the muscle extract infusion group, which however returned to normal. Arterial hemoglobin concentration and systemic vascular resistance index remained fairly stationary in both groups. Immediate significant decreases in both arterial oxygen saturation and arterial oxygen tension were observed in the muscle extract group, however both variables recovered towards the end of the experiment. A slight increase in arterial blood pH value was noted during the experiment. In conclusion, autologous muscle extract infusion causes decreases in heart rate and cardiac index, as well as a significant increase in pulmonary vascular tone and systemic hypoxemia, emphasizing the detrimental effects of skeletal muscle injury following severe trauma.  相似文献   
4.
Visual distortions may be a frightening experience. They are often incorrectly diagnosed and easily dismissed. The causes of visual distortions are poorly understood. The aim of this study was to investigate the link between visual distortions and dissociative experiences in a nonclinical population. A total of 297 nonclinical volunteers completed the Dissociative Experience Scale and answered questions concerning visual distortions. Our study suggests that visual distortions are quite common and that there is a clear link between visual distortions and dissociative phenomena. Literature indicates that this may be caused by disturbances in brain lateralization. Bilateral language capacity may interfere with abilities usually associated with the nondominant hemisphere. Research efforts attempting to shed light on the above matter may benefit our knowledge for dissociative phenomena. An interdisciplinary approach is needed.  相似文献   
5.
Cystic fibrosis (CF) is the most common autosomal recessive disorder in Caucasians. The most frequent mutation associated with cystic fibrosis has been identified as the 3 bp deletion Delta F 508. While existing polymerase chain reactions (PCR) (allele specific amplification) used to screen for CF are both sensitive and specific, we tested the prenatal application of fluorescent polymerase chain reaction and subsequent DNA fragment analysis that appears to be fast and sensitive. DNA samples (n=146) isolated from amniotic fluid (n=108), chorion villus biopsies (n=6), and human peripheral blood (n=32) were analyzed for the presence of Delta F 508 using the fluorescent method. Of these, 10 carriers of Delta F 508 mutation were detected. We achieved the same results with conventional PCR and fluorescent PCR.  相似文献   
6.
Context  Many recent cross-sectional studies have suggested that lack of early exposure to communicable diseases, including measles, in affluent countries may have increased rates of atopic disease. Objective  To study the association between natural measles infection and atopy. Design and Setting  Cross-sectional nationwide study in Finland using data gathered between November 1, 1982, and June 30, 1986. Subjects  A total of 547,910 individuals aged 14 months to 19 years who at the time of measles-mumps-rubella (MMR) vaccination had relevant information collected on the occurrence of measles and allergic rhinitis, eczema, and asthma. Main Outcome Measures  Lifetime occurrence of atopic manifestations in subjects who had had measles compared with those who had not, expressed as age-specific and age-adjusted prevalence ratios. Results  The age-adjusted prevalence ratio of atopic manifestations among those who had had measles (n = 20,690) compared with those who had not (n = 527,220) was 1.32 (95% confidence interval [CI], 1.27-1.36) for eczema, 1.41 (95% CI, 1.33-1.49) for rhinitis, and 1.67 (95% CI, 1.54-1.79) for asthma. The positive association between measles and atopy was evident at all ages, in both urban and rural dwellers, and among subjects with many or few contacts at home or in day care. Conclusions  Based on our data, measles and atopy occur more frequently together than expected, which does not support the hypothesis that experiencing natural measles infection offers protection against atopic disease.   相似文献   
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Clinical Rheumatology - Rheumatoid arthritis (RA) patients show an earlier circadian rhythm (i.e. serum melatonin peaks earlier during the night, indicating an earlier timing of the internal...  相似文献   
10.
Efficacy of salbutamol via Easyhaler unaffected by low inspiratory flow   总被引:2,自引:0,他引:2  
The fine particle dose delivered via dry powder inhalers (DPIs) is often affected by the inspiratory flow rate generated during inhalation. This has clinical implications, since the fine particle dose determines the amount of drug reaching the lungs. With Easyhaler DPI the fine particle dose remains relatively constant over the range of inspiratory flow rates from 30-60 l min(-1). The aim of this study was to confirm that clinical efficacy is maintained even at low flow rates by comparing the bronchodilating effect of salbutamol (100 microg) delivered via Easyhaler at a target inspiratory flow of 30 l min(-1) with the same dose of salbutamol via pressurised metered-dose inhaler (pMDI) plus spacer. This was a double-blind, randomized, cross-over study with double-dummy technique. Twenty-one paediatric and adult asthmatic patients completed the study, which was conducted over 2 study days. The main outcome parameter was forced expiratory volume in 1 sec (FEV1). The patients were trained to generate a low peak inspiratory flow rate (PIFR) of 30 l min(-1), and the actual PIFR through Easyhaler was recorded. The average PIFR through Easyhaler was 28.7 l min(-1). The difference in the maximum value of FEV1 (FEV1max) between the treatments after drug inhalation was 0.01 l. The mean of FEV1max was 2.67 l after pMDI plus spacer compared to 2.69 l after Easyhaler. Improvements in FEV1 were clinically significant. No significant differences between treatments were found. A reasonably low inspiratory flow rate through Easyhaler produces an equivalent improvement in lung function to a correctly used pMDI plus spacer. Hence, Easyhaler can be used with confidence in patients who may have difficulty in generating a high inspiratory flow rate, such as children and the elderly.  相似文献   
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