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71.
The present study investigated the processing of two types of artificial grammars by means of event-related brain potentials. Two categories of meaningless CV syllables were applied in each grammar type. The two grammars differed with regard to the type of the underlying rule. The finite-state grammar (FSG) followed the rule (AB)n, thereby generating local transitions between As and Bs (e.g., n=2, ABAB). The phrase structure grammar (PSG) followed the rule AnBn, thereby generating center-embedded structures in which the first A and the last B embed the middle elements (e.g., n=2, [A[AB]B]). Two sequence lengths (n=2, n=4) were used. Violations of the structures were introduced at different positions of the syllable sequences. Early violations were situated at the beginning of a sequence, and late violations were placed at the end of a sequence. A posteriorly distributed early negativity elicited by violations was present only in FSG. This effect was interpreted as the possible reflection of a violated local expectancy. Moreover, both grammar-type violations elicited a late positivity. This positivity varied as a function of the violation position in PSG, but not in FSG. These findings suggest that the late positivity could reflect difficulty of integration in PSG sequences. 相似文献
72.
目的测定甘肃产五加中剌五加苷B、苷E的含量。方法高效液相色谱法,ODSKromasal柱。水乙晴(955)为流动相,检测波长222nm,柱温度25℃。结果本文可同时测定剌五加苷B、苷E的含量。剌五加苷B、苷E分别在0.064~0.320μg/ml;0.074~0.370μg/ml范围内峰面积与浓度呈线性关系,平均回收率分别为102.5%,RSD=4.2%,95.5%,RSD=4.6%。结论剌五加苷B、苷E在红毛五加中含量最高;茎皮中含量最高;剌五加苷E的含量高于苷B。 相似文献
73.
The Impact of Migraine on Health Status 总被引:3,自引:0,他引:3
Marie-Louise Essink-Bot MD Leona van Royen MSc Paul Krabbe MSc Gouke J. Bonsel MD PhD Frans FH Rutten PhD 《Headache》1995,35(4):200-206
Problems.-What is the effect of migraine on health status, defined as the patient's physical, psychological, and social functioning? And, suppose that the health status of migraine sufferers appears to be impaired, to what extent is this a consequence of migraine-associated comorbidity rather than of migraine itself? Methods.-A group of 846 migraineurs, selected from the general population following IHS criteria, and a control group were surveyed with the Medical Outcomes Study 36-item Short-Form Health Survey, Nottingham Health Profile, EuroQol instrument, end the COOP/WONCA charts. Questions on demographic characteristics and comorbidity were included. Results.-The health status of migraineurs appeared to be significantly impaired in comparison to the control group. Because statistical significance is distinct from relevance, effect size estimators were employed. Although the direction of the differences indicated consistently a worse health status of the migraineurs, regardless of the instrument used, the sizes of the differences were small to medium. Self-reported comorbidity, especially depression, was more prevalent in the migraine group. However, this offered only a partial explanation for the impaired health status of the migraine group. Conclusions.-Migraine has an independent moderately deteriorating effect on the daily functioning of individuals. 相似文献
74.
E. Merz D. Macchiella G. Weber F. Bahlmann 《Archives of gynecology and obstetrics》1993,254(1-4):406-407
Schlu?folgerung Die transvaginale vaginosonographisch gesteuerte Methotrexat-Instillation stellt bei der frühen EUG ein erfolgreiches und
nebenwirkungsarmes konservatives Therapieverfahrendar, das ohne Narkose durchgeführt werden kann. Voraussetzung sind die eindeutige
Lokalisation der EUG und ein Trophoblastdurchmesser von maximal 15 mm.
In Kauf genommen werden müssen das Risiko eines Therapieversagens und eine relativ lange Beobachtungsphase des β-HCG-Abfalls. 相似文献
75.
人白血病HL60细胞的分化状态对细胞凋亡的影响 总被引:2,自引:0,他引:2
用细胞培养和流式细胞术等方法,研究人白血病HL60细胞诱导分化后,对三尖杉酯碱(Har)和喜树碱(Cam)诱导细胞凋亡的影响。结果表明,12-豆蔻酰及13-乙酸佛波酯以16nmol·L-1浓度处理HL60细胞24h,细胞向单核/巨噬细胞方向分化,阻断于G1期;分化细胞抗Har和Cam诱导的细胞凋亡,但其c-myc基因的表达无变化。1.4%二甲基亚砜处理HL60细胞48h,细胞向粒细胞方向分化,阻断于G1期;分化细胞抗Cam,而不抗Har诱导的细胞凋亡;分化细胞的c-myc基因表达明显下降。结果提示,人白血病HL60细胞的分化状态,明显影响三尖杉酯碱和喜树碱诱导的细胞凋亡,但可能与c-myc基因的表达变化无关。 相似文献
76.
Large-scale analyses of causes of neonatal deaths are usually based on death-certificate information. A new computer-based method has been introduced to define the cause of stillbirths and neonatal deaths in large amounts of material and to classify them according to two different models [Wigglesworth and Neonatal and Intrauterine death Classification according to (a)Etiology (NICE)]. The method is based on a combination of detailed information from health care registries and the death-certificate information. The present study aimed to compare these two classification models with a previously published method based solely on death certificate information [International Collaborative Effort (ICE)]. The study population comprised 2378 neonatal deaths in Sweden between 1987 and 1992. Cross-tabulation was made between the ICE classification and the other two classification models. In addition, case examples are presented in detail, exemplifying how classification errors arose. The ICE classification gives a rather low precision, notably for two important causes of death: asphyxia and immaturity. Among 328 infants dying from asphyxia according to computerized Wigglesworth classification, ICE classified 59% as asphyxia and 22% were labelled immaturity. When ICE classified the deaths as due to asphyxia, this was verified in only 50%. Among 792 infants dying from immaturity according to computerized Wigglesworth classification, 64% were classified as such by ICE. The findings cast doubts on the results of studies based exclusively on death-certificate information. Whenever possible in the analysis of neonatal deaths, death-certificate information should be supplemented with more detailed data. The computer-based method introduced here makes such analyses possible for large databases. 相似文献
77.
78.
Pulmonary hypoplasia was diagnosed sonographically in 32 fetuses from 20 to 33 weeks of gestation. In addition to standard biometry, transverse thoracic diameter (TTD), sagittal thoracic diameter (TSD), thoracic circumference (TC) and lung diameter (LD) were measured in all cases and compared with known nomograms. The fetuses were divided into five groups according to the main sonographic findings: group 1-skeletal dysplasia; group 2-renal agenesis; group 3-diaphragmatic hernia; group 4-hydrothorax; and group 5-others. Severe pulmonary hypoplasia (PH) was diagnosed prenatally in all cases on the basis of LD measurements. In 17 (53.1 per cent) out of 32 cases TTD was below the 5th percentile while lower TSD measurements were recorded in 15 (46.8 per cent) fetuses. A thorax circumference below the 5th percentile for the respective gestational age was found in 15 cases (46.8 per cent) and a decreased LD/TC ratio in 25 cases (78.1 per cent). In 13 out of 32 fetuses pulmonary hypoplasia was diagnosed before, and in 19 cases after 24 weeks of gestation. Pulmonary hypoplasia was confirmed by autopsy in all cases. Conclusion: pulmonary hypoplasia can be sonographically detected before 24 weeks of gestation. In cases of skeletal dysplasia and renal agenesis pulmonary hypoplasia can be diagnosed by chest and lung measurements, whereas in diaphragmatic hernia and hydrothorax diagnosis of pulmonary hypoplasia is possible only by lung measurement. 相似文献
79.
Reference values of ductus venosus flow velocities and calculated waveform indices 总被引:10,自引:0,他引:10
In recent years, investigations of the venous vascular system have become increasingly important in the assessment of fetal myocardial function. The aim of the present Doppler ultrasound study was to establish both new reference ranges for blood flow velocity during the different phases of the cardiac cycle (S, SD, D, a) and various calculated indices ((S-a)/S, (S-a)/V(mean), (S-a)D, S/D, a/S, S/a) for the ductus venosus. Pulsed-wave colour Doppler was used in this prospective cross-sectional study to examine 696 women with low-risk pregnancies during the period from 14 to 41 weeks' gestation. Reference curves were constructed for the individual measuring parameters based on a growth function from a four-parameter class of monotonic continuous functions according to the smallest square principle. A significant increase in blood flow velocity from 48 cm/s to 65.8 cm/s was observed during ventricular systole (=S) from 14 to 41 week's gestation. Similarly, increases in blood flow velocity were recorded during the endsystolic phase (=SD) (35.5 cm/s to 50.7 cm/s during early ventricular diastole (=D) (41.7 cm/s to 58 cm/s, p=0.0001) and atrial contraction (=a) (11.2 cm/s to 35 cm/s, p=0.0001), as well as for intensity-weighted mean velocity (30 cm/s to 48.3 cm/s). The venous indices were associated with significant decreases in the individual parameters with increasing gestational age: (S-a)/S from 0.77 to 0.47, (S-a)/V(mean) from 1.21 to 0.67, (S-a)/D from 0.89 to 0.54, S/a from 4.5 to 1.99. A significant increase from 0.23 to 0.53 was observed only for the quotient a/S. There were no changes in the S/D quotient (from 1.15 to 1.13). Regarding intra-observer reliability, more favourable results were obtained for calculated indices than for measurements of absolute blood flow velocities. At constant measuring conditions, the reference ranges established by this study for blood flow velocities and calculated indices in the ductus venosus may serve as the basis for Doppler ultrasound follow-up in a normal patient population as well as for the diagnosis of fetal myocardial insufficiency of hypoxic and congestive origin. 相似文献
80.
Catharina E van Ewijk Marjolein N Kooijman Ewout Fanoy Stijn FH Raven Marit Middeldorp Anita Shah Brechje de Gier Hester E de Melker Susan JM Hahn Mirjam J Knol 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(45)
BackgroundDifferential SARS-CoV-2 exposure between vaccinated and unvaccinated individuals may confound vaccine effectiveness (VE) estimates.AimWe conducted a test-negative case–control study to determine VE against SARS-CoV-2 infection and the presence of confounding by SARS-CoV-2 exposure.MethodsWe included adults tested for SARS-CoV-2 at community facilities between 4 July and 8 December 2021 (circulation period of the Delta variant). The VE against SARS-CoV-2 infection after primary vaccination with an mRNA (Comirnaty or Spikevax) or vector-based vaccine (Vaxzevria or Janssen) was calculated using logistic regression adjusting for age, sex and calendar week (Model 1). We additionally adjusted for comorbidity and education level (Model 2) and SARS-CoV-2 exposure (number of close contacts, visiting busy locations, household size, face mask wearing, contact with SARS-CoV-2 case; Model 3). We stratified by age, vaccine type and time since vaccination.ResultsVE against infection (Model 3) was 64% (95% CI: 50–73), only slightly lower than in Models 1 (68%; 95% CI: 58–76) and 2 (67%; 95% CI: 56–75). Estimates stratified by age group, vaccine and time since vaccination remained similar: mRNA VE (Model 3) among people ≥ 50 years decreased significantly (p = 0.01) from 81% (95% CI: 66–91) at < 120 days to 61% (95% CI: 22–80) at ≥ 120 days after vaccination. It decreased from 83% to 59% in Model 1 and from 81% to 56% in Model 2.ConclusionSARS-CoV-2 exposure did not majorly confound the estimated COVID-19 VE against infection, suggesting that VE can be estimated accurately using routinely collected data without exposure information. 相似文献