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121.
There is little information available concerning whether, and to what extent, migraine-prophylactic agents interfere with the symptoms of migraine attacks. The present study is a placebo-controlled, double-blind study concerning metoprolol in classic migraine. The data refer to the symptoms of single migraine attacks. During metoprolol treatment more attacks were characterized as mild (p = 0.002), and mean global rating (an integrated estimate of headache intensity and of other discomfort) was lower (4.2 versus 5.2, p = 0.003). The mean headache intensity per attack (1.97 versus 2.15) and the mean duration (5.5 versus 6.8 h) were not significantly different. Consumption of analgesics per attack was lower during metoprolol treatment (0.6 versus 1.1; p = 0.02). Attacks with associated symptoms accompanying the headache were fewer during metoprolol treatment (p = 0.014). Total visual and non-visual aura symptoms occurred with similar frequency, but scintillations and paraesthesia were more frequent during metoprolol treatment, whereas speech disturbances were less frequent. In spite of lower consumption of analgesics, the symptoms appeared milder during metoprolol than during placebo. The pattern of changes indicates that metoprolol exerts its action via the sympathetic nervous system; peripheral vasoconstriction is hardly the underlying mechanism of action.  相似文献   
122.
Compliance with antibiotic prophylaxis after urinary tract infection was assessed in 32 children, using a parent questionnaire, and a urine test for antibacterial substances. In 31 (97%) cases, parents reported giving the antibiotics every day but only 22 (69%) of urine tests were positive. Failure to understand the reasons for prophylaxis and non-compliance were significantly associated.  相似文献   
123.
In this study we investigated whether the diagnosis of sleep apnoea syndrome (SAS), based on night-time polysomnography (NPSG), can be predicted or excluded by a one-hour daytime polysomnography (DPSG). The results of 306 NPSGs were compared with DPSGs, which were performed the day before. Treated patients were excluded. In the 89 patients with SAS (Apnoea index (AI)>/=5) 59 showed apnoeas during the DPSG and 30 did not. In the 217 without SAS 25 showed apnoeas daring DPSG and 192 did not. Sensitivity for detecting SAS was 66%, the specificity was 88%, the positive predictive value (PPV) 70% and the negative predictive value (NPV) 86%. For relevant SAS (AI>/=10) the NPV would be 95%. We conclude that the one-hour DPSG is not sufficient for diagnosing or excluding SAS with certainty. It can be used to make the presence of relevant SAS unlikely.  相似文献   
124.
This study evaluated preterm infants of less than 2.3 kg birth weight fed commercial formula (Preemie SMA®) devoid of arachidonic acid (AA) and docosahexaenoic acid (DHA) and compared this control group with similar infant groups fed one of three formulas containing a range of 0.32-1.1% AA and 0.24-0.75% DHA in the fat component of the formula. An analogous group of infants fed on their mothers' breast milk and a breast milk fortifier was also studied. Individual lipoprotein fractions were isolated from blood samples collected at 12 d of age and after a further 4 wk of feeding. The fatty acid content of individual lipid components, isolated from each lipoprotein fraction was quantitatively determined in order to identify change in marker pools of essential fatty acid. The high density lipoproteins (HDL) and low density lipoproteins (LDL) phospholipid and cholesterol ester fractions contain most of the AA and DHA found in the lipoprotein fractions (total of 0.49% and 0.35%, respectively). Infants fed a formula without AA and DHA showed a reduction in AA level in the phospholipid fraction of all lipoproteins and in the HDL and LDL cholesterol ester fraction. A reduced level of DHA was also observed primarily in the lipoprotein phospholipid fraction in comparison with infants fed breast milk or infant formula containing AA and DHA. Supplementing infant formula with increasing levels of AA and DHA produced a clear dose response in the level of AA found in the HDL and LDL phospholipid fraction. From comparison of the fatty acid levels present in the lipoproteins it appears that a formula level of 0.49% AA and 0.35% DHA provides sufficient levels of these fatty acids to achieve a similar fatty acid content to that of infants fed breast milk for the major lipoprotein fractions examined.  相似文献   
125.
BACKGROUND: Although multiple studies have reported that a significant number of melanomas have diameters of less than or equal to 6 mm at the time of diagnosis, there has been only one series evaluating the proportion of melanomas less than 4 mm in diameter. OBJECTIVE: The objective of this study was to determine the proportion of melanomas, in a single-practitioner, general dermatology practice, with clinical diameters less than 4 mm. METHODS: Information regarding each new diagnosis of melanoma had been recorded during the study period of 2000-2004. Patient records and pathology reports were examined from these patients. RESULTS: Thirteen (13.7%) of the 95 melanomas had diameters less than 4 mm at the time of presentation, including five invasive and eight in situ melanomas. The defining clinical characteristic of these lesions was intensity of pigment. Three of these 13 melanomas, including one invasive and two in situ lesions, showed features of regression. CONCLUSIONS: The findings of this study support those authors who have suggested elimination of the 6-mm diameter criterion in the ABCDE rule. In addition, this study provides further evidence that dark colour as a diagnostic criterion for melanoma should be given more emphasis. The substitution of 'D' to represent dark instead of diameter is worthy of consideration to enhance the value of the ABCDE mnemonic.  相似文献   
126.
127.
A BamHI polymorphism has been identified in the human factor IX gene. This polymorphism, which occurs in approximately 6% of X chromosomes, has been used to determine the carrier status of a female in a family with a history of hemophilia B. This family was uninformative for the previously reported TaqI and Xmnl polymorphisms in the factor IX gene.  相似文献   
128.
Mapping of monoclonal antibodies to human factor IX   总被引:2,自引:1,他引:2  
We used recombinant DNA techniques to map a panel of six monoclonal antibodies (MoAbs) to regions of the human factor IX molecule. A-2 maps to 17 amino acids at the amino terminus of the heavy chain of IXa; 2D5, an inhibitor of clotting, is defined to 36 amino acids of the first EGF- like domain of human factor IX. A-4, A-5, C10D, and FXC008 all map to a region of the heavy chain containing amino acids 180 through 310, suggesting an immunodominant site. FXC008 has been reported to interfere with binding of factor IXa to factor VIII:Ca.  相似文献   
129.
Chelation therapy with deferoxamine is effective in preventing the risk of transfusional iron overload, but treatment failure is common because of noncompliance. To reduce the transfusional iron load, we have evaluated longterm erythrocytapheresis in 14 subjects with sickle cell disease and stroke (11) or other complications (3) as an alternative to simple transfusion. Subjects were treated with erythrocytapheresis using the Haemonetics V50 (Haemonetics Corp, Braintree, MA) to maintain the target pretransfusion hemoglobin S (Hb S) level less than 50% for 6 to 71 months. The transfusional iron load and the donor blood usage were analyzed for a 6- to 36-month study period and were compared with similar data from a subset of 7 subjects previously treated with conventional (target Hb S < 30%) and modified (target Hb S < 50%) simple transfusion protocols. The effect of erythrocytapheresis on iron accumulation was determined by assessment of serum ferritin levels in the absence of iron chelation. The mean transfusional iron load and donor blood usage with erythrocytapheresis were 19 +/- 14 mg iron/kg/yr (range, 6 to 50) and 188.4 +/- 55.2 mL packed-red blood cells (RBC)/kg/yr (range, 107 to 281), respectively. Of 6 subjects receiving no iron chelation therapy, 5 maintained normal or nearly normal serum ferritin levels during 11 to 36 months of erythrocytapheresis. In comparison with conventional simple transfusion and modified simple transfusion, erythrocytapheresis reduced iron loading by 87% (P < .01) and 82% (P < .01), respectively, but increased donor blood usage by 23% and 73%, respectively. Subjects with pre-erythrocytapheresis Hb levels > or = 8.0 g/dL had lower iron accumulation (P < .001) and less donor blood usage (P < .005) than subjects with Hb levels < or = 8.0 g/dL. Although donor blood usage is increased in comparison with simple transfusion, long-term erythrocytapheresis markedly reduces or prevents iron accumulation. This form of transfusion therapy allows the cessation of iron chelation in well-chelated subjects and, if used as the initial form of transfusion therapy, may prevent long-term complications of sickle cell disease without risk of iron overload and the need for chelation therapy.  相似文献   
130.
Seroepidemiology of pertussis in Italy.   总被引:5,自引:0,他引:5  
During 1988 and 1989 the prevalence of serum IgG antibodies to pertussis toxin in a sample of 3,875 unvaccinated, apparently healthy persons between the ages of 1 year to 19 years was estimated by enzyme-linked immunosorbent assay. The participants were recruited by means of systematic cluster sampling from public and private schools in five geographic areas of Italy. The overall prevalence of IgG antibodies was 80.8%, with a steady increase from 33.5% among 1- to 3-year-old children to 95% among 17- to 19-year-old individuals. The prevalence of natural immunity was 50% and 75% at the ages of 4 and 6 years, respectively. No gender-related difference in immunity was observed. For children greater than 10 years of age, the seroprevalence of pertussis antibodies was significantly higher in northern regions than in southern regions until the age of 17-19 years, when the pattern reversed. There was no association of a child's immune status with the father's number of years of schooling or with family size. For children aged 1-3 years, serologic studies showed that the history of pertussis reported by parents in questionnaires was highly specific (97.6%) in predicting antibody status, with positive and negative predictive values of 90.5% and 79.2%, respectively. However, 20.8% of children had antibodies to pertussis toxin even though they had no history of whooping cough.  相似文献   
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