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91.
Aim The aim of this article was to report the prevalence of, and risk factors for, positive autism screens using the Modified Checklist for Autism in Toddlers (M‐CHAT) in children born extremely preterm in England. Method All children born at not more than 26 weeks' gestational age in England during 2006 were recruited to the EPICure‐2 study. At 2 years of age, postal questionnaires incorporating the M‐CHAT and additional developmental questions were sent to the parents of each survivor (n=1031; 499 male, 532 female), of which 523 (266 male, 257 female; 51%) were returned completed. Results The prevalence of positive M‐CHAT screens in this extremely preterm population was 41% (216/523; 130 male; 86 female). Severe bronchopulmonary dysplasia, administration of postnatal steroids, late‐onset bacteraemia, and being male were statistically significantly associated with a positive screen. Coexisting disabilities were present in 320 (62%) children. Of 200 children without disability, 16.5% screened positive. In contrast, 63 (95.5%) of those with severe motor impairment (odds ratio 42; 95% confidence interval [CI] 12.9–135) and 175 (55.9%) of those with cognitive impairment (odds ratio 5.3; CI 3.5–8) screened positive. All children with a significant vision or hearing impairment screened positive. Interpretation The prevalence of positive M‐CHAT screens in extremely preterm children is high, especially in children with neurodevelopmental impairment. Positive screens should be interpreted in the light of other neurodevelopmental sequelae in clinical practice to avoid false‐positive referrals.  相似文献   
92.
Aims We have identified an excess of children with cerebral palsy (CP) born to women who received antibiotic treatment for spontaneous preterm labour (SPL). This nested study investigated the profile of impairment among children with CP in the ORACLE Children Study (OCS), and contrasted outcomes with those in 4Child, a population CP registry. Method The study group comprised 167 children aged from 7 to 10 years (100 males, 67 females) with CP from the OCS, who were subdivided into a preterm rupture of membranes (PROM) group (87 children) and an SPL group (80 children). The OCS sought follow‐up information regarding the health and behaviour of surviving children at 7 years of age in the UK using a parent‐report postal questionnaire. Families provided further information to define wider aspects of function and were offered a physiotherapy assessment. Results The prevalence of CP was higher among children in the OCS than among those in 4Child (standardized morbidity ratios: SPL group, 3.12 [95% confidence interval CI 2.47–3.87); PROM group: 1.56 (CI 1.24–1.92)]. The proportion of children with CP born after 32 weeks of gestation was higher in in the SPL group (73%) than in the PROM group (30%); the prevalence of CP was higher in the SPL group than in the PROM group or 4Child. Children with CP in the OCS tended to have similar distributions of neuroimpairment as children in 4Child, but motor impairment and associated vision and hearing problems were found to be less severe. Interpretation The pattern of CP in both the PROM and the SPL groups was similar, but functional outcomes were milder, compared with children with CP in the general population. However, in these groups the risk of CP was increased independently of gestational age. This is consistent with findings that ongoing inflammatory damage can cause CP.  相似文献   
93.
Blood coagulation is initiated when plasma factor VII(a) binds to its essential cofactor tissue factor (TF) and proteolytically activates factors X and IX. Progressive inhibition of TF activity occurs upon its addition to plasma. This process is reversible and requires the presence of VII(a), catalytically active Xa, Ca2+, and another component that appears to be associated with the lipoproteins in plasma, a lipoprotein-associated coagulation inhibitor (LACI). A protein, LACI(HG2), possessing the same inhibitory properties as LACI, has recently been isolated from the conditioned media of cultured human liver cells (HepG2). Rabbit antisera raised against a synthetic peptide based on the N-terminal sequence of LACI(HG2) and purified IgG from a rabbit immunized with intact LACI(HG2) inhibit the LACI activity in human serum. In a reaction mixture containing VIIa, Xa, Ca2+, and purified LACI(HG2), the apparent half-life (t1/2) for TF activity was 20 seconds. The presence of heparin accelerated the initial rate of inhibition threefold. Antithrombin III alpha alone had no effect, but antithrombin III alpha with heparin abrogated the TF inhibition. LACI(HG2) also inhibited Xa with an apparent t1/2 of 50 seconds. Heparin enhanced the rate of Xa inhibition 2.5-fold, whereas phospholipids and Ca2+ slowed the reaction 2.5-fold. Xa inhibition was demonstrable with both chromogenic substrate (S-2222) and bioassays, but no complex between Xa and LACI(HG2) could be visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Nondenaturing PAGE, however, showed that LACI(HG2) bound to Xa but not to X or Xa inactivated by diisopropyl fluorophosphate. Thus, LACI(HG2) appears to bind to Xa at or near its active site. Bovine factor Xa lacking its gamma-carboxyglutamic acid-containing domain, BXa(-GD), through treatment with alpha-chymotrypsin, was used to further investigate the Xa requirement for VIIa/TF inhibition by LACI(HG2). LACI(HG2) bound to BXa(-GD) and inhibited its catalytic activity against a small molecular substrate (Spectrozyme Xa), though at a rate approximately sevenfold slower than native BXa. Preincubation of LACI(HG2) with saturating concentrations of BXa(-GD) markedly retarded the subsequent inhibition of BXa. The VII(a)/TF complex was not inhibited by LACI(HG2) in the presence of BXa(-GD), and further, preincubation of LACI(HG2) with BXa(-GD) slowed the inhibition of VIIa/TF after the addition of native Xa. The results are consistent with the hypothesis that inhibition of VII(a)/TF involves the formation of a VIIa-TF-XA-LACI complex that requires the GD of XA.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
94.
95.
96.
Tendon echogenicity: ex vivo study   总被引:2,自引:0,他引:2  
Crass  JR; van de Vegte  GL; Harkavy  LA 《Radiology》1988,167(2):499-501
Recent publications discussing the echogenicity of normal tendon have described it variously as hyperechoic or hypoechoic. Since the echogenicity of tendon has been used to define normality and abnormality, certain knowledge of the normal echogenicity of tendon is crucial. Fresh tendon and muscle from beef hock was scanned with sector- and linear-array-transducer imaging at multiple angles and distances. The echogenicity of tendon was found to be very angle-dependent, a characteristic known as anisotropy. Scanned perpendicular to its long axis with a linear-array transducer, tendon was significantly more echogenic than muscle. With a change in angle, echogenicity of tendon decreased relative to that of muscle (the echogenicity of muscle remained the same), becoming isoechoic at angles of 2 degrees -7 degrees and hypoechoic at greater angles. Tendon studied with a sector transducer exhibited varying echogenicity. If echogenicity is used as a diagnostic criterion, the angle of the interrogating ultrasound beam must be very specifically defined.  相似文献   
97.
Omenn's disease.     
The importance of accurate pathological diagnosis is emphasised in the case of a newborn infant who presented with alopecia, a generalised erythrodermatous skin eruption, and hepatosplenomegaly. She subsequently developed generalised lymphadenopathy and recurrent septicaemia and died aged 2 months. The histological findings of widespread lymphocytic, histiocytic, and eosinophilic tissue infiltration, associated with thymic hypoplasia, were consistent with autosomal recessive Omenn''s disease.  相似文献   
98.
After severe head injury, many children continue to experience major cognitive and behavioural problems and consequent educational difficulties, even after good physical recovery. Forty three children referred to the regional multidisciplinary head injury rehabilitation team are described. The clinical outcome at a median interval of 13 months after injury showed that 18 (42%) had persistent neurological impairment and 15 (35%) had an identified need for special educational support. Thirty seven children were further assessed for psychiatric morbidity, cognitive impairment, and classroom performance. Rutter behavioural questionnaires were sent to parents and teachers of head injured index cases and classmate controls matched for age and sex. Index parents scored their children significantly worse in both 'health' and 'habits' and more cases than controls had scores suggesting a psychiatric disorder. Teachers scored index cases significantly worse for five of the traits questioned, but discriminated cases from controls less decisively than parents. Index cases were significantly disadvantaged on teachers' assessments of classroom skills and performance. A need for improved support and training of staff who teach head injured children was identified.  相似文献   
99.
100.
Summary. Between 1970 and 1976, 290 patients with endometrial cancer were treated at the 1st Obstetrics and Gynecology Clinic of the University of Milan. The median age was 62 years. Surgery was completed in 262 (90.3%) patients. Abdominal hysterectomy was used in 158 (70.9%) stage I and 40 (71.4%) stage II/III patients; vaginal hysterectomy in 55 (24.7%) stage I and nine (16.1%) stage II/III patients. Resection of the upper vagina was performed in 168 patients. Postoperative external beam radiotherapy was used in stage II/III patients and in 44 (19.7%) stage I high-risk patients. Ten-year survival, determined by the life-table method, was 84.8% in stage I (223 patients), 53.4% in stage II (37 patients), 64.4% in stage III (19 patients), and 9.1% in stage IV (11 patients). Factors associated with poorer prognosis were: late age at diagnosis (P<0.001); deep myometrial invasion (P<0.001); poorly differentiated histological grade ( P =0.11); lack of resection of the upper vagina ( P = 0.13). The role and importance of surgery is discussed, with special emphasis on the selective use of the vaginal route in aged, obese and medically high-risk patients.  相似文献   
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